Study of equatorial Kelvin waves using the MST radar and radiosonde observations

Directory of Open Access Journals (Sweden)

P. Kishore

2005-06-01

Full Text Available In this paper an attempt has been made to study equatorial Kelvin waves using a high power coherent VHF radar located at Gadanki (13.5° N, 79.2° E, a tropical station in the Indian sub-continent. Simultaneous radiosonde observations taken from a nearby meteorological station located in Chennai (13.04° N, 80.17° E were also used to see the coherence in the observed structures. These data sets were analyzed to study the mean winds and equatorial waves in the troposphere and lower stratosphere. Equatorial waves with different periodicities were identified. In the present study, particular attention has been given to the fast Kelvin wave (6.5-day and slow Kelvin wave (16-day. Mean zonal wind structures were similar at both locations. The fast Kelvin wave amplitudes were somewhat similar in both observations and the maximum amplitude is about 8m/s. The phase profiles indicated a slow downward progression. The slow Kelvin wave (16-day amplitudes shown by the radiosonde measurements are a little larger than the radar derived amplitudes. The phase profiles showed downward phase progression and it translates into a vertical wavelength of ~10-12km. The radar and radiosonde derived amplitudes of fast and slow Kelvin waves are larger at altitudes near the tropopause (15-17km, where the mean wind attains westward maximum.

Edge contact angle and modified Kelvin equation for condensation in open pores.

Science.gov (United States)

Malijevský, Alexandr; Parry, Andrew O; Pospíšil, Martin

2017-08-01

We consider capillary condensation transitions occurring in open slits of width L and finite height H immersed in a reservoir of vapor. In this case the pressure at which condensation occurs is closer to saturation compared to that occurring in an infinite slit (H=∞) due to the presence of two menisci that are pinned near the open ends. Using macroscopic arguments, we derive a modified Kelvin equation for the pressure p_{cc}(L;H) at which condensation occurs and show that the two menisci are characterized by an edge contact angle θ_{e} that is always larger than the equilibrium contact angle θ, only equal to it in the limit of macroscopic H. For walls that are completely wet (θ=0) the edge contact angle depends only on the aspect ratio of the capillary and is well described by θ_{e}≈sqrt[πL/2H] for large H. Similar results apply for condensation in cylindrical pores of finite length. We test these predictions against numerical results obtained using a microscopic density-functional model where the presence of an edge contact angle characterizing the shape of the menisci is clearly visible from the density profiles. Below the wetting temperature T_{w} we find very good agreement for slit pores of widths of just a few tens of molecular diameters, while above T_{w} the modified Kelvin equation only becomes accurate for much larger systems.

Edge contact angle and modified Kelvin equation for condensation in open pores

Science.gov (United States)

Malijevský, Alexandr; Parry, Andrew O.; Pospíšil, Martin

2017-08-01

We consider capillary condensation transitions occurring in open slits of width L and finite height H immersed in a reservoir of vapor. In this case the pressure at which condensation occurs is closer to saturation compared to that occurring in an infinite slit (H =∞ ) due to the presence of two menisci that are pinned near the open ends. Using macroscopic arguments, we derive a modified Kelvin equation for the pressure pc c(L ;H ) at which condensation occurs and show that the two menisci are characterized by an edge contact angle θe that is always larger than the equilibrium contact angle θ , only equal to it in the limit of macroscopic H . For walls that are completely wet (θ =0 ) the edge contact angle depends only on the aspect ratio of the capillary and is well described by θe≈√{π L /2 H } for large H . Similar results apply for condensation in cylindrical pores of finite length. We test these predictions against numerical results obtained using a microscopic density-functional model where the presence of an edge contact angle characterizing the shape of the menisci is clearly visible from the density profiles. Below the wetting temperature Tw we find very good agreement for slit pores of widths of just a few tens of molecular diameters, while above Tw the modified Kelvin equation only becomes accurate for much larger systems.

Molecular magnetic hysteresis at 60 kelvin in dysprosocenium

Science.gov (United States)

Goodwin, Conrad A. P.; Ortu, Fabrizio; Reta, Daniel; Chilton, Nicholas F.; Mills, David P.

2017-08-01

Lanthanides have been investigated extensively for potential applications in quantum information processing and high-density data storage at the molecular and atomic scale. Experimental achievements include reading and manipulating single nuclear spins, exploiting atomic clock transitions for robust qubits and, most recently, magnetic data storage in single atoms. Single-molecule magnets exhibit magnetic hysteresis of molecular origin—a magnetic memory effect and a prerequisite of data storage—and so far lanthanide examples have exhibited this phenomenon at the highest temperatures. However, in the nearly 25 years since the discovery of single-molecule magnets, hysteresis temperatures have increased from 4 kelvin to only about 14 kelvin using a consistent magnetic field sweep rate of about 20 oersted per second, although higher temperatures have been achieved by using very fast sweep rates (for example, 30 kelvin with 200 oersted per second). Here we report a hexa-tert-butyldysprosocenium complex—[Dy(Cpttt)2][B(C6F5)4], with Cpttt = {C5H2tBu3-1,2,4} and tBu = C(CH3)3—which exhibits magnetic hysteresis at temperatures of up to 60 kelvin at a sweep rate of 22 oersted per second. We observe a clear change in the relaxation dynamics at this temperature, which persists in magnetically diluted samples, suggesting that the origin of the hysteresis is the localized metal-ligand vibrational modes that are unique to dysprosocenium. Ab initio calculations of spin dynamics demonstrate that magnetic relaxation at high temperatures is due to local molecular vibrations. These results indicate that, with judicious molecular design, magnetic data storage in single molecules at temperatures above liquid nitrogen should be possible.

¿Qué es una onda ecuatorial de Kelvin?

OpenAIRE

Ripa, P.

1980-01-01

La importancia del estudio de las ondas de Kelvin (ecuatoriales o costeras) radica, en parte, en el hecho de que éstas proveen un mecanismo eficaz para el transporte de energía (en la forma de perturbaciones de densidad y corriente) en una dirección particular. Estas señales se trasladan sin dispersión, es decir, sin cambiar de forma. Por otra parte, una onda de Kelvin provee un ejemplo muy sencillo de dos fenómenos fundamentales de la Oceanografía Física de frecuencias: el balance geostrófic...

Kelvin probe force microscopy from single charge detection to device characterization

CERN Document Server

Glatzel, Thilo

2018-01-01

This book provides a comprehensive introduction to the methods and variety of Kelvin probe force microscopy, including technical details. It also offers an overview of the recent developments and numerous applications, ranging from semiconductor materials, nanostructures and devices to sub-molecular and atomic scale electrostatics. In the last 25 years, Kelvin probe force microscopy has developed from a specialized technique applied by a few scanning probe microscopy experts into a tool used by numerous research and development groups around the globe. This sequel to the editors’ previous volume “Kelvin Probe Force Microscopy: Measuring and Compensating Electrostatic Forces,” presents new and complementary topics. It is intended for a broad readership, from undergraduate students to lab technicians and scanning probe microscopy experts who are new to the field.

Automatic kelvin probe compatible with ultrahigh vacuum

NARCIS (Netherlands)

Baikie, I.D.; van der Werf, Kees; Oerbekke, H.; Broeze, J.; van Silfhout, Arend

1989-01-01

This article describes a new type of in situ ultrahigh‐vacuum compatible kelvin probe based on a voice‐coil driving mechanism. This design exhibits several advantages over conventional mechanical feed‐through and (in situ) piezoelectric devices in regard to the possibility of multiple probe

Investigation of Kelvin wave periods during Hai-Tang typhoon using Empirical Mode Decomposition

Science.gov (United States)

Kishore, P.; Jayalakshmi, J.; Lin, Pay-Liam; Velicogna, Isabella; Sutterley, Tyler C.; Ciracì, Enrico; Mohajerani, Yara; Kumar, S. Balaji

2017-11-01

Equatorial Kelvin waves (KWs) are fundamental components of the tropical climate system. In this study, we investigate Kelvin waves (KWs) during the Hai-Tang typhoon of 2005 using Empirical Mode Decomposition (EMD) of regional precipitation, zonal and meridional winds. For the analysis, we use daily precipitation datasets from the Global Precipitation Climatology Project (GPCP) and wind datasets from the European Centre for Medium-Range Weather Forecasts (ECMWF) Interim Re-analysis (ERA-Interim). As an additional measurement, we use in-situ precipitation datasets from rain-gauges over the Taiwan region. The maximum accumulated precipitation was approximately 2400 mm during the period July 17-21, 2005 over the southwestern region of Taiwan. The spectral analysis using the wind speed at 950 hPa found in the 2nd, 3rd, and 4th intrinsic mode functions (IMFs) reveals prevailing Kelvin wave periods of ∼3 days, ∼4-6 days, and ∼6-10 days, respectively. From our analysis of precipitation datasets, we found the Kelvin waves oscillated with periods between ∼8 and 20 days.

Kelvin Wave Influence on the Shallow-to-Deep Transition Over the Amazon

Science.gov (United States)

Rowe, A.; Serra, Y. L.

2017-12-01

The suite of observations from GOAmazon and CHUVA offers a unique opportunity to examine land-based convective processes in the tropics, including the poorly represented shallow-to-deep transition. This study uses these data to investigate impacts of Kelvin waves on the the shallow-to-deep transition over the Central Amazon. The Kelvin waves that propagate over the region often originate over the tropical central and east Pacific, with local generation over the Andes also observed. The observed 15 m s-1 phase speed and 4500 km wave length during the two-year campaign are in agreement with previously published studies of these waves across the tropics. Also in agreement with previous studies, we find the waves are most active during the wet season (November-May) for this region. Using four separate convective event classes (clear-sky, nonprecipitating cumulus congestus, afternoon deep convection, and mesoscale convective systems), we examine how the convection preferentially develops for different phases of the Kelvin waves seen during GOAmazon. We additionally examine surface meteorological variables, the vertical thermodynamic and dynamic structure of the troposphere, vertical moist static stability, integrated column water vapor and liquid water, and surface energy fluxes within the context of these convective classes to identify the important environmental factors contributing to observed periods of enhanced deep convection related to the waves. Results suggest that the waves significantly modify the local environment, such as creating a deep layer of moisture throughout the troposphere, favoring more organized convection in the active than in the suppressed phase of the wave. The significance of wave-related environmental modifications are assessed by comparing local rainfall accumulations during Kelvin wave activity to that when the waves are not present. Future work will further explore the shallow-to-deep transition and its modulation by Kelvin wave activity

Progress towards a new definition of the kelvin

Science.gov (United States)

Fischer, Joachim

2015-10-01

At its 24th meeting (2011) the General Conference on Weights and Measures noted the CIPM’s intention to express new definitions of the kilogram, ampere, kelvin, and mole in terms of fixed numerical values of the Planck constant, elementary charge, Boltzmann constant, and Avogadro constant, respectively. The changes proposed for the International System of Units will not actually be adopted until the experimental results on the new definitional constants that are proposed have reached a further stage of refinement. This paper provides an overview of the activities and progress of the research groups who are carrying out experiments to determine the Boltzmann constant. The most promising methods, acoustic gas thermometry, dielectric-constant gas thermometry, Johnson noise thermometry and Doppler-broadening thermometry, are reviewed. The prospects for meeting the requirements of the Consultative Committee for Thermometry for a new definition of the kelvin are discussed.

Noise performance of frequency modulation Kelvin force microscopy

Directory of Open Access Journals (Sweden)

Heinrich Diesinger

2014-01-01

Full Text Available Noise performance of a phase-locked loop (PLL based frequency modulation Kelvin force microscope (FM-KFM is assessed. Noise propagation is modeled step by step throughout the setup using both exact closed loop noise gains and an approximation known as “noise gain” from operational amplifier (OpAmp design that offers the advantage of decoupling the noise performance study from considerations of stability and ideal loop response. The bandwidth can be chosen depending on how much noise is acceptable and it is shown that stability is not an issue up to a limit that will be discussed. With thermal and detector noise as the only sources, both approaches yield PLL frequency noise expressions equal to the theoretical value for self-oscillating circuits and in agreement with measurement, demonstrating that the PLL components neither modify nor contribute noise. Kelvin output noise is then investigated by modeling the surrounding bias feedback loop. A design rule is proposed that allows choosing the AC modulation frequency for optimized sharing of the PLL bandwidth between Kelvin and topography loops. A crossover criterion determines as a function of bandwidth, temperature and probe parameters whether thermal or detector noise is the dominating noise source. Probe merit factors for both cases are then established, suggesting how to tackle noise performance by probe design. Typical merit factors of common probe types are compared. This comprehensive study is an encouraging step toward a more integral performance assessment and a remedy against focusing on single aspects and optimizing around randomly chosen key values.

Effect of plasma density profile of tokamak on Kelvin-Helmholtz instability

International Nuclear Information System (INIS)

Tang Fulin

1984-01-01

The purpose of this paper is to study the effect of radial distribution of plasma density profile of tokamak on Kelvin-Helmholtz instability caused by toroidal rotation. The effect of radial distribution of plasma rotational velocity on stability is also examine for comparison. It is found that within the range of tokamak parameters the only radial distribution of plasma rotational velocity cannot induce Kelvin-Helmholtz instability. On the contrary, when there is a radial distribution of plasma density, i.e. P 01 =P 0 e -tx and V 0 1 = const, plasma becomes unstable, and instability will increase proportionally to the value of t. Meanwhile when the value of t remains constant, the instability growth rate will decrease if P 0 grows or the distance between plasma and wall of container decreases too. It shows that the Kelvin-Helmoltz instability is not only influenced by the steepness of density profile but also by the inertia of plasma in central region, which is helpful for depressing the instability. (author). 5 refs, 4 figs, 2 tabs

Rayleigh-Taylor and Kelvin-Helmholtz instabilities in targets accelerated by laser ablation

International Nuclear Information System (INIS)

Emery, M.H.; Gardner, J.H.; Boris, J.P.

1982-01-01

With use of the fast2d laser-shell model, the acceleration of a 20-μm-thick plastic foil up to 160 km/s has been simulated. It is possible to follow the Rayleigh-Taylor bubble-and-spike development far into the nonlinear regime and beyond the point of foil fragmentation. Strong shear flow develops which evolves into the Kelvin-Helmholtz instability. The Kelvin-Helmholtz instability causes the tips of the spikes to widen and as a result reduce their rate of ''fall.''

Observations of Convectively Coupled Kelvin Waves forced by Extratropical Wave Activity

Science.gov (United States)

Kiladis, G. N.; Biello, J. A.; Straub, K. H.

2012-12-01

It is well established by observations that deep tropical convection can in certain situations be forced by extratropical Rossby wave activity. Such interactions are a well-known feature of regions of upper level westerly flow, and in particular where westerlies and equatorward wave guiding by the basic state occur at low enough latitudes to interact with tropical and subtropical moisture sources. In these regions convection is commonly initiated ahead of upper level troughs, characteristic of forcing by quasi-geostrophic dynamics. However, recent observational evidence indicates that extratropical wave activity is also associated with equatorial convection even in regions where there is a "critical line" to Rossby wave propagation at upper levels, that is, where the zonal phase speed of the wave is equal to the zonal flow speed. A common manifestation of this type of interaction involves the initiation of convectively coupled Kelvin waves, as well as mixed Rossby-gravity (MRG) waves. These waves are responsible for a large portion of the convective variability within the ITCZ over the Indian, Pacific, and Atlantic sectors, as well as within the Amazon Basin of South America. For example, Kelvin waves originating within the western Pacific ITCZ are often triggered by Rossby wave activity propagating into the Australasian region from the South Indian Ocean extratropics. At other times, Kelvin waves are seen to originate along the eastern slope of the Andes. In the latter case the initial forcing is sometimes linked to a low-level "pressure surge," initiated by wave activity propagating equatorward from the South Pacific storm track. In yet other cases, such as over Africa, the forcing appears to be related to wave activity in the extratropics which is not necessarily propagating into low latitudes, but appears to "project" onto the Kelvin structure, in line with past theoretical and modeling studies. Observational evidence for extratropical forcing of Kelvin and MRG

KELVIN rare gas time-of-flight program

International Nuclear Information System (INIS)

Vernon, M.

1981-03-01

The purpose of this appendix is to explain in detail the procedure for performing time-of-flight (TOF) calibration measurements. The result of the calibration measurements is to assign a correct length (L) to the path the molecules travel in a particular experimental configuration. In conjunction with time information (t) a velocity distribution (L/t) can then be determined. The program KELVIN is listed

The Kelvin-Thomson atom

International Nuclear Information System (INIS)

Walton, A.J.

1977-01-01

The contributions made by Kelvin and later by J.J. Thomson to the 'current-bun' model of the atom are discussed. It is felt that the model is worth retaining as a didactic aid since it serves as a good example around which to hang a discussion of modelling as well as providing good examples of the application of Coulomb's and Gauss's laws. The structure of atoms containing up to six electrons is examined using an analysis based on this model. It is shown that it is possible to have a mechanically stable arrangement of up to six electrons located within a sphere of uniform positive charge. With up to three electrons the arrangement is coplanar with the centre of the sphere. (U.K.)

Kelvin-Helmholtz Instability: Lessons Learned and Ways Forward

Science.gov (United States)

Masson, A.; Nykyri, K.

2018-06-01

The Kelvin-Helmholtz instability (KHI) is a ubiquitous phenomenon across the Universe, observed from 500 m deep in the oceans on Earth to the Orion molecular cloud. Over the past two decades, several space missions have enabled a leap forward in our understanding of this phenomenon at the Earth's magnetopause. Key results obtained by these missions are first presented, with a special emphasis on Cluster and THEMIS. In particular, as an ideal instability, the KHI was not expected to produce mass transport. Simulations, later confirmed by spacecraft observations, indicate that plasma transport in Kelvin-Helmholtz (KH) vortices can arise during non-linear stage of its development via secondary process. In addition to plasma transport, spacecraft observations have revealed that KHI can also lead to significant ion heating due to enhanced ion-scale wave activity driven by the KHI. Finally, we describe what are the upcoming observational opportunities in 2018-2020, thanks to a unique constellation of multi-spacecraft missions including: MMS, Cluster, THEMIS, Van Allen Probes and Swarm.

Kelvin Equation for a Non-Ideal Multicomponent Mixture

DEFF Research Database (Denmark)

Shapiro, Alexander; Stenby, Erling Halfdan

1997-01-01

The Kelvin equation is generalized by application to a case of a multicomponent non-ideal mixture. Such a generalization is necessary in order to describe the two-phase equilibrium in a capillary medium with respect to both normal and retrograde condensation. The equation obtained is applied...... to the equilibrium state of a hydrocarbon mixture ina gas-condensate reservoir....

Pressure-driven ballistic Kelvin's water dropper for energy harvesting

NARCIS (Netherlands)

Xie, Yanbo; de Boer, Hans L.; van den Berg, Albert; Sprenkels, A.J.; Eijkel, Jan C.T.

2014-01-01

In this paper, we introduce a microfluidic-based self-excited energy conversion system inspired by Kelvin's water dropper but driven by inertia instead of gravity. Two micro water jets are produced by forcing water through two micropores by overpressure. The jets break up into microdroplets which

Numerical Prediction of Wave Patterns Due to Motion of 3D Bodies by Kelvin-Havelock Sources

Directory of Open Access Journals (Sweden)

Ghassemi Hassan

2016-12-01

Full Text Available This paper discusses the numerical evaluation of the hydrodynamic characteristics of submerged and surface piercing moving bodies. Generally, two main classes of potential methods are used for hydrodynamic characteristic analysis of steady moving bodies which are Rankine and Kelvin-Havelock singularity distribution. In this paper, the Kelvin- Havelock sources are used for simulating the moving bodies and then free surface wave patterns are obtained. Numerical evaluation of potential distribution of a Kelvin-Havelock source is completely presented and discussed. Numerical results are calculated and presented for a 2D cylinder, single source, two parallel moving source, sphere, ellipsoid and standard Wigley hull in different situation that show acceptable agreement with results of other literatures or experiments.

Vertical propagation of baroclinic Kelvin waves along the west coast ...

Indian Academy of Sciences (India)

Second, baroclinic Kelvin waves generated in the Bay of Bengal at periods shorter than about 120 ... significant energy remains trapped to the Indian west coast. .... ary condition, enables us to isolate the response of the West India Coastal ...

Magnetized Kelvin-Helmholtz instability: theory and simulations in the Earth's magnetosphere context

Science.gov (United States)

Faganello, Matteo; Califano, Francesco

2017-12-01

The Kelvin-Helmholtz instability, proposed a long time ago for its role in and impact on the transport properties at magnetospheric flanks, has been widely investigated in the Earth's magnetosphere context. This review covers more than fifty years of theoretical and numerical efforts in investigating the evolution of Kelvin-Helmholtz vortices and how the rich nonlinear dynamics they drive allow solar wind plasma bubbles to enter into the magnetosphere. Special care is devoted to pointing out the main advantages and weak points of the different plasma models that can be adopted for describing the collisionless magnetospheric medium and in underlying the important role of the three-dimensional geometry of the system.

Equatorial atmospheric Kelvin waves during El Niño episodes and their effect on stratospheric QBO

International Nuclear Information System (INIS)

Das, Uma; Pan, C.J.

2016-01-01

Equatorial atmospheric Kelvin waves are investigated during a positive El Niño Southern Oscillation (ENSO) episode using temperature data retrieved from GPS Radio Occultation (RO) observations of FORMOSAT-3/COSMIC during the period from August 2006 to December 2013. Enhanced Kelvin wave amplitudes are observed during the El Niño episode of 2009–2010 and it is also observed that these amplitudes correlate with the Niño 3.4 index and also with outgoing longwave radiation and trade wind index. This study indicates that the enhanced equatorial atmospheric Kelvin wave amplitudes might be produced by geophysical processes that were involved in the onset and development of the El Niño episode. Further, easterly winds above the tropopause during this period favored the vertically upward propagation of these waves that induced a fast descending westerly regime by the end of 2010, where the zero-wind line is observed to take only 5 months to descend from 10 to 50 hPa. The current study presents observational evidence of enhanced Kelvin wave amplitudes during El Niño that has affected the stratospheric quasi-biennial oscillation (QBO) through wave–mean flow interactions. Earlier El Niño episodes of 1987 and 1998 are also qualitatively investigated, using reanalysis data. It is found that there might have been an enhancement in the equatorial Kelvin wave amplitudes during almost all El Niño episodes, however, an effect of a fast descending westerly is observed in the QBO only when the ambient zonal winds in the lower stratosphere favor the upward propagation of the Kelvin waves and consequently they interact with the mean flow. This study indicates that the El Niño and QBO are not linearly related and wave mean flow interactions play a very important role in connecting these two geophysical phenomena. - Highlights: • Enhanced atmospheric Kelvin Wave amplitudes observed during El Nino of 2010. • The waves are probably produced by processes generating El Nino. �

Equatorial atmospheric Kelvin waves during El Niño episodes and their effect on stratospheric QBO

Energy Technology Data Exchange (ETDEWEB)

Das, Uma [Department of Physics, University of New Brunswick, Fredericton (Canada); Pan, C.J., E-mail: cjpan@jupiter.ss.ncu.edu.tw [Institute of Space Science, National Central University, Jhongli, Taiwan (China)

2016-02-15

Equatorial atmospheric Kelvin waves are investigated during a positive El Niño Southern Oscillation (ENSO) episode using temperature data retrieved from GPS Radio Occultation (RO) observations of FORMOSAT-3/COSMIC during the period from August 2006 to December 2013. Enhanced Kelvin wave amplitudes are observed during the El Niño episode of 2009–2010 and it is also observed that these amplitudes correlate with the Niño 3.4 index and also with outgoing longwave radiation and trade wind index. This study indicates that the enhanced equatorial atmospheric Kelvin wave amplitudes might be produced by geophysical processes that were involved in the onset and development of the El Niño episode. Further, easterly winds above the tropopause during this period favored the vertically upward propagation of these waves that induced a fast descending westerly regime by the end of 2010, where the zero-wind line is observed to take only 5 months to descend from 10 to 50 hPa. The current study presents observational evidence of enhanced Kelvin wave amplitudes during El Niño that has affected the stratospheric quasi-biennial oscillation (QBO) through wave–mean flow interactions. Earlier El Niño episodes of 1987 and 1998 are also qualitatively investigated, using reanalysis data. It is found that there might have been an enhancement in the equatorial Kelvin wave amplitudes during almost all El Niño episodes, however, an effect of a fast descending westerly is observed in the QBO only when the ambient zonal winds in the lower stratosphere favor the upward propagation of the Kelvin waves and consequently they interact with the mean flow. This study indicates that the El Niño and QBO are not linearly related and wave mean flow interactions play a very important role in connecting these two geophysical phenomena. - Highlights: • Enhanced atmospheric Kelvin Wave amplitudes observed during El Nino of 2010. • The waves are probably produced by processes generating El Nino. �

Variations of Kelvin waves around the TTL region during the stratospheric sudden warming events in the Northern Hemisphere winter

Directory of Open Access Journals (Sweden)

Y. Jia

2016-03-01

Full Text Available Spatial and temporal variabilities of Kelvin waves during stratospheric sudden warming (SSW events are investigated by the ERA-Interim reanalysis data, and the results are validated by the COSMIC temperature data. A case study on an exceptionally large SSW event in 2009, and a composite analysis comprising 18 events from 1980 to 2013 are presented. During SSW events, the average temperature increases by 20 K in the polar stratosphere, while the temperature in the tropical stratosphere decreases by about 4 K. Kelvin wave with wave numbers 1 and 2, and periods 10–20 days, clearly appear around the tropical tropopause layer (TTL during SSWs. The Kelvin wave activity shows obvious coupling with the convection localized in the India Ocean and western Pacific (Indo-Pacific region. Detailed analysis suggests that the enhanced meridional circulation driven by the extratropical planetary wave forcing during SSW events leads to tropical upwelling, which further produces temperature decrease in the tropical stratosphere. The tropical upwelling and cooling consequently result in enhancement of convection in the equatorial region, which excites the strong Kelvin wave activity. In addition, we investigated the Kelvin wave acceleration to the eastward zonal wind anomalies in the equatorial stratosphere during SSW events. The composite analysis shows that the proportion of Kelvin wave contribution ranges from 5 to 35 % during SSWs, much larger than in the non-SSW mid-winters (less than 5 % in the stratosphere. However, the Kelvin wave alone is insufficient to drive the equatorial eastward zonal wind anomalies during the SSW events, which suggests that the effects of other types of equatorial waves may not be neglected.

Detection of the fast Kelvin wave teleconnection due to El Niño-Southern Oscillation

Science.gov (United States)

Meyers, Steven D.; Melsom, Arne; Mitchum, Gary T.; O'Brien, James J.

1998-11-01

Previous analyses of the ocean state along the western American coast have often indicated unexpectedly slow and limited propagation of coastally trapped Kelvin waves associated with the El Niño-Southern Oscillation. In contrast, theoretical and numerical ocean models demonstrate that these Kelvin waves are a rapid and long-range teleconnection between the low- and high-latitude Pacific Ocean, strongly impacting both the surface coastal currents and nutrient upwelling. Sea level variations along the western coast of North America are reexamined under the assumption that tropically forced Kelvin waves are produced in bursts of several months duration. A cross-correlation analysis, restricted to mid-1982 to mid-1983, is performed between Galapagos Island and stations along western Central and North America. A coastally trapped Kelvin wave is revealed to propagate at a speed of 2-3 m s-1 from the tropical Pacific to the Aleutian Island Chain. The observed phase speed agrees with the estimated speed of a Kelvin wave based on the average density profile of the ocean near the coast. Weaker El Niño events in 1986/1987 and 1991/1992 appear to contain a combination of this remote signal and local wind forcing. The wave propagation speed calculated from the spectral phase is shown to be sensitive to the presence of other (noise) processes in the observations. This is demonstrated through an analysis of a synthetic sea level data set that contains many of the essential features of the real sea level data. A relatively small level of red noise can give a 100% expected error in the estimated propagation speed. This suggests a new explanation for this important inconsistency within dynamical oceanography.

Mechanic-electrical transformations in the Kelvin method

Energy Technology Data Exchange (ETDEWEB)

Zharkikh, Yu. S., E-mail: yurzhar@gmail.com [Faculty of Radio Physics, Electronics and Computer Systems, Taras Shevchenko National University of Kyiv, 4G, Ave. Academician Glushkov, 03127, Kyiv (Ukraine); Lysochenko, S.V., E-mail: lys@univ.kiev.ua [Institute of High Technologies, Taras Shevchenko National University of Kyiv, 4G, Ave. Academician Glushkov, 03127, Kyiv (Ukraine)

2017-04-01

Highlights: • Used in Kelvin method dynamic capacitor is a mechanic-electrical transformer. • The oscillations of its plate are source of extraneous forces which cause the appearance of an electric current. • The signal is caused not by the contact potential difference, but by oscillation in the screening conditions of charge in the dynamic capacitor gap. • Combining the Kelvin method with electron emission methods to determine the work function may lead to incorrectness. - Abstract: To explain the initiation mechanism of alternating current in an electric circuit containing the dynamic capacitor a model of mechanic- electrical transformation is suggested to use. In such a model, electric charges disposed between the capacitor plates serve as a cause of measured signal in contrast to the contact potential difference, which is considered as the main base in the Kelvin’s model. If one of the plates moves periodically, then the conditions of the charges screening are changed and thereby the capacitor recharging current is arise. The measuring is based on compensation of the recharging current by current, which generated by a source of electromotive force (EMF). The compensation voltage depends on both the distribution of ions or dipoles over the studied surface and the charges creating the surface potential barrier. This voltage is independent on the bulk electro-physical characteristics of a solid.

The Evolution of the Celsius and Kelvin Temperature Scales and the State of the Art

Science.gov (United States)

Pellicer, Julio; Amparo Gilabert, M.; Lopez-Baeza, Ernesto

1999-07-01

A physical analysis is given of the evolution undergone by the Celsius and Kelvin temperature scales, from their definition to the present day. It is shown that in the temperature interval between the melting point of ice and the boiling point of water, the Celsius and Kelvin scales, both born centigrade by definition and actually become so afterwards by experimental determination as well, are not so any longer, either by definition or by experimental determination.

Coupled Kelvin-Helmholtz and Tearing Mode Instabilities at the Mercury's Magnetopause

Science.gov (United States)

Ivanovski, S. L.; Milillo, A.; Kartalev, M.; Massetti, S.

2018-05-01

A MHD approach for numerical simulations of coupled Kelvin-Helmholtz and tearing mode instabilities has been applied to Mercury’s magnetopause and used to perform a physical parameters study constrained by the MESSENGER data.

Can Hall effect trigger Kelvin-Helmholtz instability in sub-Alfvénic flows?

Science.gov (United States)

Pandey, B. P.

2018-05-01

In the Hall magnetohydrodynamics, the onset condition of the Kelvin-Helmholtz instability is solely determined by the Hall effect and is independent of the nature of shear flows. In addition, the physical mechanism behind the super- and sub-Alfvénic flows becoming unstable is quite different: the high-frequency right circularly polarized whistler becomes unstable in the super-Alfvénic flows whereas low-frequency, left circularly polarized ion-cyclotron wave becomes unstable in the presence of sub-Alfvénic shear flows. The growth rate of the Kelvin-Helmholtz instability in the super-Alfvénic case is higher than the corresponding ideal magnetohydrodynamic rate. In the sub-Alfvénic case, the Hall effect opens up a new, hitherto inaccessible (to the magnetohydrodynamics) channel through which the partially or fully ionized fluid can become Kelvin-Helmholtz unstable. The instability growth rate in this case is smaller than the super-Alfvénic case owing to the smaller free shear energy content of the flow. When the Hall term is somewhat smaller than the advection term in the induction equation, the Hall effect is also responsible for the appearance of a new overstable mode whose growth rate is smaller than the purely growing Kelvin-Helmholtz mode. On the other hand, when the Hall diffusion dominates the advection term, the growth rate of the instability depends only on the Alfvén -Mach number and is independent of the Hall diffusion coefficient. Further, the growth rate in this case linearly increases with the Alfvén frequency with smaller slope for sub-Alfvénic flows.

Zero Kelvin Big Bang, an Alternative Paradigm: I. Logic and the Cosmic Fabric

Science.gov (United States)

Haynes, Royce

2011-11-01

This is the first of three papers describing an alternative paradigm of cosmogony, the beginning and evolution of the universe. The Zero Kelvin Big Bang (ZKBB) theory is compared to the prevailing Standard Big Bang (SBB) paradigm, and challenges the notion that our universe is "all there is." Logic suggests that the Big Bang was not a creation event, but that the universe did have a beginning: a "cosmic fabric" of pre- existing matter, in pre-existing space. Instead, the Zero Kelvin Big Bang was a transitional event between that "beginning" and what would become our universe. Extrapolating entropy back in time (as SBB does for matter and energy), and applying simple logic, suggests a "cosmic fabric" of the simplest, stable particles of matter, at the lowest energy state possible: singlet state, spin-oriented atomic hydrogen at zero kelvin, at a density of, at most, only a few atoms per cubic meter of space, infinite and (almost) eternal. Papers II and III describe the condensation of part of the cosmic fabric into a Bose-Einstein condensate (BEC) as Lemaître's primeval atom, followed by an implosion- explosion Big Bang.

Kelvin probe microscopy and electronic transport measurements in reduced graphene oxide chemical sensors

Science.gov (United States)

Kehayias, Christopher E.; MacNaughton, Samuel; Sonkusale, Sameer; Staii, Cristian

2013-06-01

Reduced graphene oxide (RGO) is an electronically hybrid material that displays remarkable chemical sensing properties. Here, we present a quantitative analysis of the chemical gating effects in RGO-based chemical sensors. The gas sensing devices are patterned in a field-effect transistor geometry, by dielectrophoretic assembly of RGO platelets between gold electrodes deposited on SiO2/Si substrates. We show that these sensors display highly selective and reversible responses to the measured analytes, as well as fast response and recovery times (tens of seconds). We use combined electronic transport/Kelvin probe microscopy measurements to quantify the amount of charge transferred to RGO due to chemical doping when the device is exposed to electron-acceptor (acetone) and electron-donor (ammonia) analytes. We demonstrate that this method allows us to obtain high-resolution maps of the surface potential and local charge distribution both before and after chemical doping, to identify local gate-susceptible areas on the RGO surface, and to directly extract the contact resistance between the RGO and the metallic electrodes. The method presented is general, suggesting that these results have important implications for building graphene and other nanomaterial-based chemical sensors.

Kelvin probe microscopy and electronic transport measurements in reduced graphene oxide chemical sensors.

Science.gov (United States)

Kehayias, Christopher E; MacNaughton, Samuel; Sonkusale, Sameer; Staii, Cristian

2013-06-21

Reduced graphene oxide (RGO) is an electronically hybrid material that displays remarkable chemical sensing properties. Here, we present a quantitative analysis of the chemical gating effects in RGO-based chemical sensors. The gas sensing devices are patterned in a field-effect transistor geometry, by dielectrophoretic assembly of RGO platelets between gold electrodes deposited on SiO2/Si substrates. We show that these sensors display highly selective and reversible responses to the measured analytes, as well as fast response and recovery times (tens of seconds). We use combined electronic transport/Kelvin probe microscopy measurements to quantify the amount of charge transferred to RGO due to chemical doping when the device is exposed to electron-acceptor (acetone) and electron-donor (ammonia) analytes. We demonstrate that this method allows us to obtain high-resolution maps of the surface potential and local charge distribution both before and after chemical doping, to identify local gate-susceptible areas on the RGO surface, and to directly extract the contact resistance between the RGO and the metallic electrodes. The method presented is general, suggesting that these results have important implications for building graphene and other nanomaterial-based chemical sensors.

The 17/5 spectrum of the Kelvin-wave cascade

OpenAIRE

Kozik, Evgeny; Svistunov, Boris

2010-01-01

Direct numeric simulation of the Biot-Savart equation readily resolves the 17/5 spectrum of the Kelvin-wave cascade from the 11/3 spectrum of the non-local (in the wavenumber space) cascade scenario by L'vov and Nazarenko. This result is a clear-cut visualisation of the unphysical nature of the 11/3 solution, which was established earlier on the grounds of symmetry.

Reflection of equatorial Kelvin waves at eastern ocean boundaries Part I: hypothetical boundaries

Directory of Open Access Journals (Sweden)

J. Soares

1999-06-01

Full Text Available A baroclinic shallow-water model is developed to investigate the effect of the orientation of the eastern ocean boundary on the behavior of equatorial Kelvin waves. The model is formulated in a spherical polar coordinate system and includes dissipation and non-linear terms, effects which have not been previously included in analytical approaches to the problem. Both equatorial and middle latitude response are considered given the large latitudinal extent used in the model. Baroclinic equatorial Kelvin waves of intraseasonal, seasonal and annual periods are introduced into the domain as pulses of finite width. Their subsequent reflection, transmission and dissipation are investigated. It is found that dissipation is very important for the transmission of wave energy along the boundary and for reflections from the boundary. The dissipation was found to be dependent not only on the presence of the coastal Kelvin waves in the domain, but also on the period of these coastal waves. In particular the dissipation increases with wave period. It is also shown that the equatorial β-plane approximation can allow an anomalous generation of Rossby waves at higher latitudes. Nonlinearities generally have a small effect on the solutions, within the confines of this model.Key words. Oceanography: general (equatorial oceanography; numerical modeling · Oceanography: physical (eastern boundary currents

Preventing probe induced topography correlated artifacts in Kelvin Probe Force Microscopy

NARCIS (Netherlands)

Polak, L.; Wijngaarden, Rinke J.

2016-01-01

Kelvin Probe Force Microscopy (KPFM) on samples with rough surface topography can be hindered by topography correlated artifacts. We show that, with the proper experimental configuration and using homogeneously metal coated probes, we are able to obtain amplitude modulation (AM) KPFM results on a

Observations of Equatorial Kelvin Wave Modes in FORMOSAT-3/COSMIC GPS RO Temperature Profiles

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Potula Sree Brahmanandam

2010-01-01

Full Text Available In this study, we analyze FORMOSAT-3/COSMIC (F3/C GPS radio occultation (RO derived temperature components for the period September 2006 to February 2008. Results show the presence of slow Kelvin waves (wave period > 10 days with higher zonal wavenumbers (either one or two in the upper troposphere and lower stratosphere (UTLS. The vertical wavelengths of these waves are found to be in the range of 5 - 12 km. The predominant Kelvin waves observed in the temperature fluctuations are in the altitude range between 15 and 28 km and centered on the tropical tropopause. The downward phase progression of these waves suggests that the derived waves are propagating upward, with the source region located at lower altitudes possibly due to tropical convective heating. The zonal winds retrieved using radiosonde observations over Singapore (1¢XN, 104¢XE during this period show a periodicity of ~24 - 26 months in the stratosphere, and quasi-biennial oscillation (QBO characteristics with eastward zonal winds from March 2006 to May 2007 and westward winds from June 2007 to July 2008 respectively. Our results further show that the Kelvin wave characteristics are enhanced during the westward phase of QBO and diminish during the eastward phase, in line with the previous reported results. Furthermore, an examination of outgoing longwave radiation (OLR data shows that deep convection activity is developed episodically over the Indonesian archipelago during the observation period, thereby indicating that the Kelvin wave events observed in temperature fluctuations are either driven by convective activity (convectively coupled waves or by a broad spectrum of convective variability (free waves over the Indonesian region.

Convectively coupled Kelvin waves in aquachannel simulations: 2. Life cycle and dynamical-convective coupling

Science.gov (United States)

Blanco, Joaquín. E.; Nolan, David S.; Mapes, Brian E.

2016-10-01

This second part of a two-part study uses Weather Research and Forecasting simulations with aquachannel and aquapatch domains to investigate the time evolution of convectively coupled Kelvin waves (CCKWs). Power spectra, filtering, and compositing are combined with object-tracking methods to assess the structure and phase speed propagation of CCKWs during their strengthening, mature, and decaying phases. In this regard, we introduce an innovative approach to more closely investigate the wave (Kelvin) versus entity (super cloud cluster or "SCC") dualism. In general, the composite CCKW structures represent a dynamical response to the organized convective activity. However, pressure and thermodynamic fields in the boundary layer behave differently. Further analysis of the time evolution of pressure and low-level moist static energy finds that these fields propagate eastward as a "moist" Kelvin wave (MKW), faster than the envelope of organized convection or SCC. When the separation is sufficiently large the SCC dissipates, and a new SCC generates to the east, in the region of strongest negative pressure perturbations. We revisit the concept itself of the "coupling" between convection and dynamics, and we also propose a conceptual model for CCKWs, with a clear distinction between the SCC and the MKW components.

Kelvin-Helmholtz instability in a weakly ionized layer

OpenAIRE

Shadmehri, Mohsen; Downes, Turlough P.

2007-01-01

We study the linear theory of Kelvin-Helmholtz instability in a layer of ions and neutrals with finite thickness. In the short wavelength limit the thickness of the layer has a negligible effect on the growing modes. However, perturbations with wavelength comparable to layer's thickness are significantly affected by the thickness of the layer. We show that the thickness of the layer has a stabilizing effect on the two dominant growing modes. Transition between the modes not only depends on th...

Pumping liquid metal at high temperatures up to 1,673 kelvin

Science.gov (United States)

Amy, C.; Budenstein, D.; Bagepalli, M.; England, D.; Deangelis, F.; Wilk, G.; Jarrett, C.; Kelsall, C.; Hirschey, J.; Wen, H.; Chavan, A.; Gilleland, B.; Yuan, C.; Chueh, W. C.; Sandhage, K. H.; Kawajiri, Y.; Henry, A.

2017-10-01

Heat is fundamental to power generation and many industrial processes, and is most useful at high temperatures because it can be converted more efficiently to other types of energy. However, efficient transportation, storage and conversion of heat at extreme temperatures (more than about 1,300 kelvin) is impractical for many applications. Liquid metals can be very effective media for transferring heat at high temperatures, but liquid-metal pumping has been limited by the corrosion of metal infrastructures. Here we demonstrate a ceramic, mechanical pump that can be used to continuously circulate liquid tin at temperatures of around 1,473-1,673 kelvin. Our approach to liquid-metal pumping is enabled by the use of ceramics for the mechanical and sealing components, but owing to the brittle nature of ceramics their use requires careful engineering. Our set-up enables effective heat transfer using a liquid at previously unattainable temperatures, and could be used for thermal storage and transport, electric power production, and chemical or materials processing.

Reproductive solutions for the g-Navier-Stokes and g-Kelvin-Voight equations

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Luis Friz

2016-01-01

Full Text Available This article presents the existence of reproductive solutions of g-Navier-Stokes and g-Kelvin-Voight equations. In this way, for weak solutions, we reach basically the same result as for classic Navier-Stokes equations.

Collisionless Kelvin-Helmholtz instability and vortex-induced reconnection in the external region of the Earth magnetotail

International Nuclear Information System (INIS)

Pegoraro, F; Faganello, M; Califano, F

2008-01-01

In a magnetized plasma streaming with a non uniform velocity, the Kelvin-Helmholtz instability plays a major role in mixing different plasma regions and in stretching the magnetic field lines leading to the formation of layers with a sheared magnetic field where magnetic field line reconnection can take place. A relevant example is provided by the formation of a mixing layer between the Earth's magnetosphere and the solar wind at low latitudes during northward periods. In the considered configuration, in the presence of a magnetic field nearly perpendicular to the plane defined by the velocity field and its inhomogeneity direction, velocity shear drives a Kelvin-Helmholtz instability which advects and distorts the magnetic field configuration. If the Alfven velocity associated to the in-plane magnetic field is sufficiently weak with respect to the variation of the fluid velocity in the plasma, the Kelvin-Helmholtz instability generates fully rolled-up vortices which advect the magnetic field lines into a complex configuration, causing the formation of current layers along the inversion curves of the in-plane magnetic field component. Pairing of the vortices generated by the Kelvin-Helmholtz instability is a well know phenomenon in two-dimensional hydrodynamics. Here we investigate the development of magnetic reconnection during the vortex pairing process and show that completely different magnetic structures are produced depending on how fast the reconnection process develops on the time scale set by the pairing process.

Epitaxial growth of pentacene on alkali halide surfaces studied by Kelvin probe force microscopy.

Science.gov (United States)

Neff, Julia L; Milde, Peter; León, Carmen Pérez; Kundrat, Matthew D; Eng, Lukas M; Jacob, Christoph R; Hoffmann-Vogel, Regina

2014-04-22

In the field of molecular electronics, thin films of molecules adsorbed on insulating surfaces are used as the functional building blocks of electronic devices. Control of the structural and electronic properties of the thin films is required for reliably operating devices. Here, noncontact atomic force and Kelvin probe force microscopies have been used to investigate the growth and electrostatic landscape of pentacene on KBr(001) and KCl(001) surfaces. We have found that, together with molecular islands of upright standing pentacene, a new phase of tilted molecules appears near step edges on KBr. Local contact potential differences (LCPD) have been studied with both Kelvin experiments and density functional theory calculations. Our images reveal that differently oriented molecules display different LCPD and that their value is independent of the number of molecular layers. These results point to the formation of an interface dipole, which may be explained by a partial charge transfer from the pentacene to the surface. Moreover, the monitoring of the evolution of the pentacene islands shows that they are strongly affected by dewetting: Multilayers build up at the expense of monolayers, and in the Kelvin images, previously unknown line defects appear, which reveal the epitaxial growth of pentacene crystals.

The influence of surface topography on Kelvin probe force microscopy

International Nuclear Information System (INIS)

Sadewasser, S; Leendertz, C; Streicher, F; Lux-Steiner, M Ch

2009-01-01

Long-range electrostatic forces govern the imaging mechanism in electrostatic force microscopy as well as in Kelvin probe force microscopy. To improve the analysis of such images, simulations of the electrostatic field distribution have been performed in the past using a flat surface and a cone-shaped tip. However, the electrostatic field distribution between a tip and a sample depends strongly on the surface topography, which has been neglected in previous studies. It is therefore of general importance to study the influence of sample topography features on Kelvin probe force microscopy images, which we address here by performing finite element simulations. We show how the surface potential measurement is influenced by surface steps and surface grooves, considering potential variations in the form of a potential peak and a potential step. The influence of the topography on the measurement of the surface potential is found to be rather small compared to a typical experimental resolution. Surprisingly, in the case of a coinciding topography and potential step an improvement of the potential profile due to the inclusion of the topography is observed. Finally, based on the obtained results, suggestions for the realization of KPFM measurement are given.

Impact of wall potential on the fluid-wall interaction in a cylindrical capillary and a generalized Kelvin equation

International Nuclear Information System (INIS)

Jakubov, T.S.; Mainwaring, D.E.

2006-01-01

In the present work a generalized Kelvin equation for a fluid confined in thick-walled cylindrical capillary is developed. This has been accomplished by including the potential energy function for interaction between a solid wall of a capillary and a confined fluid into the Kelvin equation. Using the Lennard-Jones 12-6 potential, an explicit form of the potential energy functions as expressed by hypergeometrical functions have been derived-firstly, for the interaction between a solid wall and a test atom placed at an arbitrary point in a long open-end capillary, and thereafter for the body-body interaction between the solid wall and a confined Lennard-Jones fluid. Further, this generalized Kelvin equation has been applied to detailed description hysteresis phenomena in such capillaries. All numerical calculations have been carried out for the model argon-graphite system at 90 K

Fractional Generalizations of Maxwell and Kelvin-Voigt Models for Biopolymer Characterization.

Directory of Open Access Journals (Sweden)

Bertrand Jóźwiak

Full Text Available The paper proposes a fractional generalization of the Maxwell and Kelvin-Voigt rheological models for a description of dynamic behavior of biopolymer materials. It was found that the rheological models of Maxwell-type do not work in the case of modeling of viscoelastic solids, and the model which significantly better describes the nature of changes in rheological properties of such media is the modified fractional Kelvin-Voigt model with two built-in springpots (MFKVM2. The proposed model was used to describe the experimental data from the oscillatory and creep tests of 3% (w/v kuzu starch pastes, and to determine the values of their rheological parameters as a function of pasting time. These parameters provide a lot of additional information about structure and viscoelastic properties of the medium in comparison to the classical analysis of dynamic curves G' and G" and shear creep compliance J(t. It allowed for a comprehensive description of a wide range of properties of kuzu starch pastes, depending on the conditions of pasting process.

ANALYSIS OF THE ELECTROPHYSICAL AND PHOTOELECTRIC PROPERTIES OF NANOCOMPOSITE POLYMERS BY THE MODIFIED KELVIN PROBE

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K. U. Pantsialeyeu

2017-01-01

Full Text Available At present for analysis of the homogeneity of materials properties are becoming widely used various modifications of a scanning Kelvin probe. These methods allow mapping the spatial distribution of the electrostatic potential. Analysis of the electropotential profile is not sufficient to describe any specific physical parameters of the polymer nanocomposites. Therefore, we use an external energy impact, such as light. Purpose of paper is the modification of the Kelvin scanning probe and the conduct of experimental studies of the spatial distribution and response of the electrostatic potential of the actual polymer nanocomposites to the optical probing.Carried out the investigations on experimental Low density polyethylene composites. Carbon nanomaterials and nanoparticles of silicon dioxide or aluminum as fillers are used. As a result, maps of the spatial distribution of the electrostatic potential relative values and the surface photovoltage. Statistical analysis of the electrophysical and photoelectric properties homogeneity, depending on the component composition of the composites carried out. In addition, with reference to matrix polymers, the Kelvin scanning probe, in combination with the optical probing, made it possible to detect a piezoelectric effect. The latter, can used as a basis for the development of new methods for studying the mechanical properties of matrix polymers.

The SAO and Kelvin waves in the EuroGRIPS GCMS and the UK Met. Office analyses

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M. Amodei

Full Text Available We compare the tropical oscillations and planetary scale Kelvin waves in four troposphere-stratosphere climate models and the assimilated dataset produced by the United Kingdom Meteorological Office (UKMO. The comparison has been made in the GRIPS framework "GCM-Reality Intercomparison Project for SPARC", where SPARC is Stratospheric Processes and their Role in Climate, a project of the World Climate Research Program. The four models evaluated are European members of GRIPS: the UKMO Unified Model (UM, the model of the Free University in Berlin (FUB–GCM, the ARPEGE-climat model of the French National Centre for Meteorological Research (CNRM, and the Extended UGAMP GCM (EUGCM of the Centre for Global Atmospheric Modelling (CGAM. The integrations were performed with different, but annually periodic external conditions (e.g., sea-surface temperature, sea ice, and incoming solar radiation. The structure of the tropical winds and the strengths of the Kelvin waves are examined. In the analyses where the SAO (Semi-Annual Oscillation and the QBO (Quasi-Biennal Oscillation are reasonably well captured, the amplitude of these analysed Kelvin waves is close to that observed in independent data from UARS (Upper Atmosphere Research Satellite. In agreement with observations, the Kelvin waves generated in the models propagate into the middle atmosphere as wave packets, consistent with a convective forcing origin. In three of the models, slow Kelvin waves propagate too high and their amplitudes are overestimated in the upper stratosphere and in the mesosphere, the exception is the UM which has weaker waves. None of the modelled waves are sufficient to force realistic eastward phases of the QBO or SAO. Although the SAO is represented by all models, only two of them are able to generate westerlies between 10 hPa and 50 hPa. The importance of the role played in the SAO by unresolved gravity waves is emphasized. Although it exhibits some unrealistic features, the

The SAO and Kelvin waves in the EuroGRIPS GCMS and the UK Met. Office analyses

Directory of Open Access Journals (Sweden)

M. Amodei

2001-01-01

Full Text Available We compare the tropical oscillations and planetary scale Kelvin waves in four troposphere-stratosphere climate models and the assimilated dataset produced by the United Kingdom Meteorological Office (UKMO. The comparison has been made in the GRIPS framework "GCM-Reality Intercomparison Project for SPARC", where SPARC is Stratospheric Processes and their Role in Climate, a project of the World Climate Research Program. The four models evaluated are European members of GRIPS: the UKMO Unified Model (UM, the model of the Free University in Berlin (FUB–GCM, the ARPEGE-climat model of the French National Centre for Meteorological Research (CNRM, and the Extended UGAMP GCM (EUGCM of the Centre for Global Atmospheric Modelling (CGAM. The integrations were performed with different, but annually periodic external conditions (e.g., sea-surface temperature, sea ice, and incoming solar radiation. The structure of the tropical winds and the strengths of the Kelvin waves are examined. In the analyses where the SAO (Semi-Annual Oscillation and the QBO (Quasi-Biennal Oscillation are reasonably well captured, the amplitude of these analysed Kelvin waves is close to that observed in independent data from UARS (Upper Atmosphere Research Satellite. In agreement with observations, the Kelvin waves generated in the models propagate into the middle atmosphere as wave packets, consistent with a convective forcing origin. In three of the models, slow Kelvin waves propagate too high and their amplitudes are overestimated in the upper stratosphere and in the mesosphere, the exception is the UM which has weaker waves. None of the modelled waves are sufficient to force realistic eastward phases of the QBO or SAO. Although the SAO is represented by all models, only two of them are able to generate westerlies between 10 hPa and 50 hPa. The importance of the role played in the SAO by unresolved gravity waves is emphasized. Although it exhibits some unrealistic features, the

CFD simulation of Kelvin-Helmholtz instability

International Nuclear Information System (INIS)

Strubelj, L.; Tiselj, I.

2005-01-01

Kelvin-Helmholtz instability appears in stratified two-fluid flow at surface. When the relative velocity is higher than the critical relative velocity, the growth of waves occurs. The experiment of Thorpe [1] used as a benchmark in the present paper, is made in a rectangular glass tube filled with two immiscible fluids of various densities. We simulated the growth of instability with CFX-5.7 code and compared simulation with analytical solution. It was found that surface tension force, which stabilizes growth of waves, actually has a destabilizing effect in simulation, unless very small timestep and residual is used. In CFX code system of nonlinear Navier-Stokes equations is linearised and solved iterative in each timestep, until prescribed residual is achieved. On the other hand, simulation without surface tension force is more stable than analytical result predicts. (author)

Kelvin Notation for Stabilizing Elastic-Constant Inversion Notation Kelvin pour stabiliser l'inversion de constantes élastiques

Directory of Open Access Journals (Sweden)

Dellinger J.

2006-12-01

Full Text Available Inverting a set of core-sample traveltime measurements for a complete set of 21 elastic constants is a difficult problem. If the 21 elastic constants are directly used as the inversion parameters, a few bad measurements or an unfortunate starting guess may result in the inversion converging to a physically impossible solution . Even given perfect data, multiple solutions may exist that predict the observed traveltimes equally well. We desire the inversion algorithm to converge not just to a physically possible solution, but to the best(i. e. most physically likely solution of all those allowed. We present a new parameterization that attempts to solve these difficulties. The search space is limited to physically realizable media by making use of the Kelvin eigenstiffness-eigentensor representation of the 6 x 6 elastic stiffness matrix. Instead of 21 stiffnesses, there are 6 eigenstiffness parametersand 15 rotational parameters . The rotational parameters are defined using a Lie-algebra representation that avoids the artificial degeneracies and coordinate-system bias that can occur with standard polar representations. For any choice of these 21 real parameters, the corresponding stiffness matrix is guaranteed to be physically realizable. Furthermore, all physically realizable matrices can be represented in this way. This new parameterization still leaves considerable latitude as to which linear combinations of the Kelvin parameters to use, and how they should be ordered. We demonstrate that by careful choice and ordering of the parameters, the inversion can be relaxedfrom higher to lower symmetry simply by adding a few more parameters at a time. By starting from isotropy and relaxing to the general result in stages (isotropy, transverse isotropy, orthorhombic, general, we expect that the method should find the solution that is closest to isotropy of all those that fit the data. L'inversion d'un ensemble de mesures du temps de parcours d

Using Paraffin PCM, Cryogel and TEC to Maintain Comet Surface Sample Cold from Earth Approach Through Retrieval

Science.gov (United States)

Choi, Michael K.

2017-01-01

An innovative thermal design concept to maintain comet surface samples cold (for example, 263 degrees Kelvin, 243 degrees Kelvin or 223 degrees Kelvin) from Earth approach through retrieval is presented. It uses paraffin phase change material (PCM), Cryogel insulation and thermoelectric cooler (TEC), which are commercially available.

Equatorial Kelvin Waves Observed with GPS Occultation Measurements : CHAMP and SAC-C (2.Space-Borne GPS Meteorology and Related Techniques)

OpenAIRE

Ho-Fang, TSAI; Toshitaka, TSUDA; George A., HAJJ; Jens, WICKERT; Yuichi, AOYAMA; Radio Science Center for Space and Atmosphere (RASC), Kyoto University :National Space Program Office(NSPO); Radio Science Center for Space and Atmosphere (RASC), Kyoto University; Jet Propulsion Laboratory (JPL), California Institute of Technology; GeoForschungsZentrum Potsdam (GFZ), Department 1:Geodesy and Remote Sensing; RASC, Kyoto University

2004-01-01

Structure and propagation of equatorial Kelvin waves during May 2001 and December 2002 are observed from the temperature profiles in the upper troposphere and the lower stratosphere using CHAMP and SAC-C GPS radio occultation data. Kelvin waves derived from temperature fluctuations characterize eastward phase propagation in time-longitude section and eastward phase tilts with height in altitude-longitude section between 10 and 30 km. The phase progression spans the range indicating the contin...

Density-space potential phase difference in a Kelvin--Helmholtz instability

International Nuclear Information System (INIS)

Glowienka, J.C.; Jennings, W.C.; Hickok, R.L.

1974-01-01

The low-frequency instability found in a hollow cathode discharge in helium was studied using an ion beam probe as a primary diagnostic tool. Three aspects of the instability are discussed: the location and amplitude of the oscillation and its correlation with the shape of the space potential; the phase angle between density and space potential oscillations; and the comparison of the data with three known instability models: Kelvin--Helmholtz, Rayleigh--Taylor, and drift waves--for mode identification. (U.S.)

Measuring the lateral charge-carrier mobility in metal-insulator-semiconductor capacitors via Kelvin-probe.

Science.gov (United States)

Milotti, Valeria; Pietsch, Manuel; Strunk, Karl-Philipp; Melzer, Christian

2018-01-01

We report a Kelvin-probe method to investigate the lateral charge-transport properties of semiconductors, most notably the charge-carrier mobility. The method is based on successive charging and discharging of a pre-biased metal-insulator-semiconductor stack by an alternating voltage applied to one edge of a laterally confined semiconductor layer. The charge carriers spreading along the insulator-semiconductor interface are directly measured by a Kelvin-probe, following the time evolution of the surface potential. A model is presented, describing the device response for arbitrary applied biases allowing the extraction of the lateral charge-carrier mobility from experimentally measured surface potentials. The method is tested using the organic semiconductor poly(3-hexylthiophene), and the extracted mobilities are validated through current voltage measurements on respective field-effect transistors. Our widely applicable approach enables robust measurements of the lateral charge-carrier mobility in semiconductors with weak impact from the utilized contact materials.

Measuring the lateral charge-carrier mobility in metal-insulator-semiconductor capacitors via Kelvin-probe

Science.gov (United States)

Milotti, Valeria; Pietsch, Manuel; Strunk, Karl-Philipp; Melzer, Christian

2018-01-01

We report a Kelvin-probe method to investigate the lateral charge-transport properties of semiconductors, most notably the charge-carrier mobility. The method is based on successive charging and discharging of a pre-biased metal-insulator-semiconductor stack by an alternating voltage applied to one edge of a laterally confined semiconductor layer. The charge carriers spreading along the insulator-semiconductor interface are directly measured by a Kelvin-probe, following the time evolution of the surface potential. A model is presented, describing the device response for arbitrary applied biases allowing the extraction of the lateral charge-carrier mobility from experimentally measured surface potentials. The method is tested using the organic semiconductor poly(3-hexylthiophene), and the extracted mobilities are validated through current voltage measurements on respective field-effect transistors. Our widely applicable approach enables robust measurements of the lateral charge-carrier mobility in semiconductors with weak impact from the utilized contact materials.

Edge Contact Angle and Modified Kelvin Equation for Condensation in Open Pores.

Czech Academy of Sciences Publication Activity Database

Malijevský, Alexandr; Parry, A.O.; Pospíšil, M.

2017-01-01

Roč. 96, č. 2 (2017), č. článku 020801. ISSN 2470-0045 R&D Projects: GA ČR(CZ) GA17-25100S Grant - others:EPSRC(GB) EP/L020564/1 Institutional support: RVO:67985858 Keywords : capillary condensation * Kelvin equation * density functional theory Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 2.366, year: 2016

Fractional order creep model for dam concrete considering degree of hydration

Science.gov (United States)

Huang, Yaoying; Xiao, Lei; Bao, Tengfei; Liu, Yu

2018-05-01

Concrete is a material that is an intermediate between an ideal solid and an ideal fluid. The creep of concrete is related not only to the loading age and duration, but also to its temperature and temperature history. Fractional order calculus is a powerful tool for solving physical mechanics modeling problems. Using a software element based on the generalized Kelvin model, a fractional order creep model of concrete considering the loading age and duration is established. Then, the hydration rate of cement is considered in terms of the degree of hydration, and the fractional order creep model of concrete considering the degree of hydration is established. Moreover, uniaxial tensile creep tests of dam concrete under different curing temperatures were conducted, and the results were combined with the creep test data and complex optimization method to optimize the parameters of a new creep model. The results show that the fractional tensile creep model based on hydration degree can better describe the tensile creep properties of concrete, and this model involves fewer parameters than the 8-parameter model.

Current Trends in Associate Degree Nursing Programs.

Science.gov (United States)

Blackstone, Elaine Grant

This study was designed to ascertain current trends in associate degree nursing programs and to discover innovative ideas and techniques which could be applied to the existing program at Miami-Dade Community College (Florida). Data was compiled from interviews with representatives of ten associate degree nursing programs in six states. Information…

Effect of cold plasma on the Kelvin-Helmholtz instability

International Nuclear Information System (INIS)

Melander, B.G.

1978-01-01

The thesis studies the effect of a two-component plasma (hot and cold) on the shear driven Kelvin-Helmholtz instability. An ion distribution with a shear flow parallel to the ambient magnetic field and a density gradient parallel to the shear direction is used. Both the electrostatic and electromagnetic versions of the instability are studied in the limit of hydromagnetic frequencies. The dispersion relation is obtained in the electrostatic case by solving the Vlasov equation for the perturbed ion and electron densities and then using the quasineutrality condition. In the electromagnetic case the coupled Vlasov and Maxwell's equations are solved to obtain the dispersion relation

The dynamics of beltramized flows and its relation with the Kelvin waves

International Nuclear Information System (INIS)

Gonzalez, Rafael; Santini, E Sergio

2011-01-01

We define the beltramized flow as the sum of an uniform translation and an uniform rotation with a Beltrami flow. Some of their features are studied by solving the Euler equations, for different geometries, taking into account the boundary conditions, and for different symmetries. We show that the Kelvin waves are beltramized flows. Finally, we show that the variational principle found in a previous work, remains valid for the beltramized flow.

The dynamics of beltramized flows and its relation with the Kelvin waves

Energy Technology Data Exchange (ETDEWEB)

Gonzalez, Rafael [Instituto de Desarrollo Humano, Universidad Nacional de General Sarmiento Pcia. de Buenos Aires, Argentina and Depto. de Fisica FCEyN, Universidad de Buenos Aires, Buenos Aires (Argentina); Santini, E Sergio, E-mail: rgonzale@ungs.edu.ar [Instituto de Ciencias, Universidad Nacional de General Sarmiento Pcia. de Buenos Aires (Argentina) and ICRA-BR, Centro Brasileiro de Pesquisas Fisicas, Rio de Janeiro (Brazil)

2011-05-01

We define the beltramized flow as the sum of an uniform translation and an uniform rotation with a Beltrami flow. Some of their features are studied by solving the Euler equations, for different geometries, taking into account the boundary conditions, and for different symmetries. We show that the Kelvin waves are beltramized flows. Finally, we show that the variational principle found in a previous work, remains valid for the beltramized flow.

A study of cross-bridge kelvin resistor structures for reliable measurement of low contact resistances

NARCIS (Netherlands)

Stavitski, N.; Klootwijk, J.H.; van Zeijl, H.W.; Kovalgin, Alexeij Y.; Wolters, Robertus A.M.

2008-01-01

The parasitic factors that strongly influence the measurement accuracy of Cross-Bridge Kelvin Resistor (CBKR) structures for low specific contact resistances (�?c) have been extensively discussed during last few decades and the minimum of the �?c value, which could be accurately extracted, was

Simulated Interannual Modulation of Intraseasonal Kelvin Waves in the Equatorial Indian Ocean

Directory of Open Access Journals (Sweden)

Iskhaq Iskandar

2016-12-01

Full Text Available Outputs from a high-resolution ocean general circulation model (OGCM for the period of 1990-2003 indicate an interannual modulation of intraseasonal Kelvin waves along the equatorial Indian Ocean. During normal conditions without IOD event, the first mode explains about 30-40% of the total variance in the western (60-65ºE and central (75-80ºE basin, while the second mode contributes up to 45% to the total variance in the central basin around the longitude of 82ºE. In contrast, during the 1997/98 IOD event, the fourth mode caused about 40% of the total variance in the central and eastern basin. During the 1994 IOD event, the contribution from the fourth baroclinic mode in the eastern basin caused 45% of the total variance. In the central basin, the second and the fourth baroclinic mode caused almost the same variance (~40%. The variations in the characteristics of the intraseasonal Kelvin waves are related to variations in the vertical stratification. During the IOD event, the pycnocline in the eastern basin was raised by about 50 m and the stratification at the upper level is strengthened, while it is weakened at lower levels. These changes lead to an increase in the contribution of higher-order baroclinic modes.

Comparative Study on Cushion Performance Between 3D Printed Kelvin Structure and 3D Printed Lattice Structure

Science.gov (United States)

Priyadarshini, Lakshmi

Frequently transported packaging goods are more prone to damage due to impact, jolting or vibration in transit. Fragile goods, for example, glass, ceramics, porcelain are susceptible to mechanical stresses. Hence ancillary materials like cushions play an important role when utilized within package. In this work, an analytical model of a 3D cellular structure is established based on Kelvin model and lattice structure. The research will provide a comparative study between the 3D printed Kelvin unit structure and 3D printed lattice structure. The comparative investigation is based on parameters defining cushion performance such as cushion creep, indentation, and cushion curve analysis. The applications of 3D printing is in rapid prototyping where the study will provide information of which model delivers better form of energy absorption. 3D printed foam will be shown as a cost-effective approach as prototype. The research also investigates about the selection of material for 3D printing process. As cushion development demands flexible material, three-dimensional printing with material having elastomeric properties is required. Further, the concept of cushion design is based on Kelvin model structure and lattice structure. The analytical solution provides the cushion curve analysis with respect to the results observed when load is applied over the cushion. The results are reported on basis of attenuation and amplification curves.

Collision-Induced Infrared Absorption by Hydrogen-Helium gas mixtures at Thousands of Kelvin

Science.gov (United States)

Abel, Martin; Frommhold, Lothar; Li, Xiaoping; Hunt, Katharine L. C.

2010-10-01

The interaction-induced absorption by collisional pairs of H2 molecules is an important opacity source in the atmospheres of the outer planets and cool stars ^[1]. The emission spectra of cool white dwarf stars differ significantly in the infrared from the expected blackbody spectra of their cores, which is largely due to absorption by collisional H2--H2, H2--He, and H2--H complexes in the stellar atmospheres. Using quantum-chemical methods we compute the atmospheric absorption from hundreds to thousands of kelvin ^[2]. Laboratory measurements of interaction-induced absorption spectra by H2 pairs exist only at room temperature and below. We show that our results reproduce these measurements closely ^[2], so that our computational data permit reliable modeling of stellar atmosphere opacities even for the higher temperatures ^[2]. [1] L. Frommhold, Collision-Induced Absorption in Gases, Cambridge University Press, Cambridge, New York, 1993 and 2006 [2] Xiaoping Li, Katharine L. C. Hunt, Fei Wang, Martin Abel, and Lothar Frommhold, ``Collision-Induced Infrared Absorption by Molecular Hydrogen Pairs at Thousands of Kelvin'', International Journal of Spectroscopy, vol. 2010, Article ID 371201, 11 pages, 2010. doi: 10.1155/2010/371201

Wave resistance calculation method combining Green functions based on Rankine and Kelvin source

Directory of Open Access Journals (Sweden)

LI Jingyu

2017-12-01

Full Text Available [Ojectives] At present, the Boundary Element Method(BEM of wave-making resistance mostly uses a model in which the velocity distribution near the hull is solved first, and the pressure integral is then calculated using the Bernoulli equation. However,the process of this model of wave-making resistance is complex and has low accuracy.[Methods] To address this problem, the present paper deduces a compound method for the quick calculation of ship wave resistance using the Rankine source Green function to solve the hull surface's source density, and combining the Lagally theorem concerning source point force calculation based on the Kelvin source Green function so as to solve the wave resistance. A case for the Wigley model is given.[Results] The results show that in contrast to the thin ship method of the linear wave resistance theorem, this method has higher precision, and in contrast to the method which completely uses the Kelvin source Green function, this method has better computational efficiency.[Conclusions] In general, the algorithm in this paper provides a compromise between precision and efficiency in wave-making resistance calculation.

Evidence of Boundary Reflection of Kelvin and First-Mode Rossby Waves from Topex/Poseidon Sea Level Data

Science.gov (United States)

Boulanger, Jean-Philippe; Fu, Lee-Lueng

1996-01-01

The TOPEX/POSEIDON sea level data lead to new opportunities to investigate some theoretical mechanisms suggested to be involved in the El Nino-Southern Oscillation phenomenon in the tropical Pacific ocean. In particular, we are interested in studying the western boundary reflection, a process crucial for the delayed action oscillator theory, by using the TOPEX/POSEIDON data from November 1992 to May 1995. We first projected the sea level data onto Kelvin and first-mode Ross waves. Then we estimated the contribution of wind forcing to these waves by using a single baroclinic mode simple wave model forced by the ERS-1 wind data. Wave propagation was clearly observed with amplitudes well explained by the wind forcing in the ocean interior. Evidence of wave reflection was detected at both the western and eastern boundaries of the tropical Pacific ocean. At the eastern boundary, Kelvin waves were seen to reflect as first-mode Rossby waves during the entire period. The reflection efficiency (in terms of wave amplitude) of the South American coasts was estimated to be 80% of that of an infinite meridional wall. At the western boundary, reflection was observed in April-August 1993, in January-June 1994, and, later, in December 1994 to February 1995. Although the general roles of these reflection events in the variability observed in the equatorial Pacific ocean are not clear, the data suggest that the reflections in January-June 1994 have played a role in the onset of the warm conditions observed in late 1994 to early 1995. Indeed, during the January-June 1994 period, as strong downwelling first-mode Rossby waves reflected into downwelling Kelvin waves, easterly wind and cold sea surface temperature anomalies located near the date line weakened and eventually reversed in June-July 1994. The presence of the warm anomalies near the date line then favored convection and westerly wind anomalies that triggered strong downwelling Kelvin waves propagating throughout the basin

Survival and vigour of ultra-dry seeds after ten years of hermetic storage

NARCIS (Netherlands)

Hong, T.D.; Ellis, R.H.; Astley, D.; Pinnegar, A.E.; Groot, S.P.C.; Kraak, H.L.

2005-01-01

Seeds of carrot, groundnut, lettuce, oilseed rape and onion were stored hermetically in laminated aluminium foil packets in four environments (dry or ultra-dry moisture contents combined factorially with temperatures of 20 degrees C or -20 degrees C), replicated at several sites. After ten years'

The Kelvin-Helmholtz instability on the magnetopause

International Nuclear Information System (INIS)

Kivelson, M.G.; California Univ., Los Angeles; Pu, Z.-Y.

1984-01-01

Conditions for the development of Kelvin-Helmholtz (K-H) waves on the magnetopause have been known for more than 15 years; more recently, spacecraft observations have stimulated further examination of the properties of K-H waves. For a magnetopause with no boundary layer, two different modes of surface waves have been identified and their properties have been investigated for various assumed orientations of magnetic field and flow velocity vectors. The power radiated into the magnetosphere from the velocity shear at the boundary has been estimated. Other calculations have focused on the consequences of finite thickness boundary layers, both uniform and non-uniform. The boundary layer is found to modify the wave modes present at the magnetopause and to yield a criterion for the wavelength of the fastest growing surface waves. The paper concludes by questioning the extent to which the inferences from boundary layer models are model dependent and identifies areas where further work is needed or anticipated. (author)

Role of interannual Kelvin wave propagations in the equatorial Atlantic on the Angola Benguela Current system

Science.gov (United States)

Imbol Koungue, Rodrigue Anicet; Illig, Serena; Rouault, Mathieu

2017-06-01

The link between equatorial Atlantic Ocean variability and the coastal region of Angola-Namibia is investigated at interannual time scales from 1998 to 2012. An index of equatorial Kelvin wave activity is defined based on Prediction and Research Moored Array in the Tropical Atlantic (PIRATA). Along the equator, results show a significant correlation between interannual PIRATA monthly dynamic height anomalies, altimetric monthly Sea Surface Height Anomalies (SSHA), and SSHA calculated with an Ocean Linear Model. This allows us to interpret PIRATA records in terms of equatorial Kelvin waves. Estimated phase speed of eastward propagations from PIRATA equatorial mooring remains in agreement with the linear theory, emphasizing the dominance of the second baroclinic mode. Systematic analysis of all strong interannual equatorial SSHA shows that they precede by 1-2 months extreme interannual Sea Surface Temperature Anomalies along the African coast, which confirms the hypothesis that major warm and cold events in the Angola-Benguela current system are remotely forced by ocean atmosphere interactions in the equatorial Atlantic. Equatorial wave dynamics is at the origin of their developments. Wind anomalies in the Western Equatorial Atlantic force equatorial downwelling and upwelling Kelvin waves that propagate eastward along the equator and then poleward along the African coast triggering extreme warm and cold events, respectively. A proxy index based on linear ocean dynamics appears to be significantly more correlated with coastal variability than an index based on wind variability. Results show a seasonal phasing, with significantly higher correlations between our equatorial index and coastal SSTA in October-April season.

Examination of biogenic selenium-containing nanosystems based on polyelectrolyte complexes by atomic force, Kelvin probe force and electron microscopy methods

Energy Technology Data Exchange (ETDEWEB)

Sukhanova, T. E., E-mail: tat-sukhanova@mail.ru; Vylegzhanina, M. E.; Valueva, S. V.; Volkov, A. Ya.; Kutin, A. A. [Institute of Macromolecular Compounds RAS, 199004 Bolshoy Pr., 31, St.-Petersburg (Russian Federation); Temiryazeva, M. P.; Temiryazev, A. G. [Kotel’nikov Institute of Radio Engineering and Electronics (Fryazino Branch) Russian Academy of Sciences, Fryazino, Moscow region, 141190 (Russian Federation)

2016-06-17

The morphology and electrical properties of biogenic selenium-containing nanosystems based on polyelectrolyte complexes (PECs) were examined using AFM, Kelvin Probe Force and electron microscopy methods. It has been found, that prepared nanostructures significantly differed in their morphological types and parameters. In particular, multilayers capsules can be produced via varying synthesis conditions, especially, the selenium–PEC mass ratio ν. At the “special point” (ν = 0.1), filled and hollow nano- and microcapsules are formed in the system. The multilayer character of the capsules walls is visible in the phase images. Kelvin Probe Force images showed the inhomogeneity of potential distribution in capsules and outside them.

Cross-Bridge Kelvin resistor structures for reliable measurement of low contact resistances and contact interface characterization

NARCIS (Netherlands)

Stavitski, N.; Klootwijk, J.H.; van Zeijl, H.W.; Kovalgin, Alexeij Y.; Wolters, Robertus A.M.

2009-01-01

The parasitic factors that strongly influence the measurement accuracy of Cross-Bridge Kelvin Resistor (CBKR) structures for low specific contact resistances (�?�c) have been extensively discussed during last few decades and the minimum of the �?�c value, which could be accurately extracted, was

Kelvin-Helmholtz instability for a bounded plasma flow in a longitudinal magnetic field

International Nuclear Information System (INIS)

Burinskaya, T. M.; Shevelev, M. M.; Rauch, J.-L.

2011-01-01

Kelvin-Helmholtz MHD instability in a plane three-layer plasma is investigated. A general dispersion relation for the case of arbitrarily orientated magnetic fields and flow velocities in the layers is derived, and its solutions for a bounded plasma flow in a longitudinal magnetic field are studied numerically. Analysis of Kelvin-Helmholtz instability for different ion acoustic velocities shows that perturbations with wavelengths on the order of or longer than the flow thickness can grow in an arbitrary direction even at a zero temperature. Oscillations excited at small angles with respect to the magnetic field exist in a limited range of wavenumbers even without allowance for the finite width of the transition region between the flow and the ambient plasma. It is shown that, in a low-temperature plasma, solutions resulting in kink-like deformations of the plasma flow grow at a higher rate than those resulting in quasi-symmetric (sausage-like) deformations. The transverse structure of oscillatory-damped eigenmodes in a low-temperature plasma is analyzed. The results obtained are used to explain mechanisms for the excitation of ultra-low-frequency long-wavelength oscillations propagating along the magnetic field in the plasma sheet boundary layer of the Earth’s magnetotail penetrated by fast plasma flows.

Distinction between magnesium diboride and tetraboride by kelvin probe force microscopy

International Nuclear Information System (INIS)

Kim, Du-Na; Caron, Arnaud; Park, Hai Woong

2016-01-01

We analyze mixtures of magnesium diboride and tetraboride synthesized with magnesium powders of different shapes. To distinguish between magnesium diboride and tetraboride we use the contrast of kelvin probe force microscopy. The microstructural morphology strongly depends on the shape of the magnesium powders used in the reaction between magnesium and magnesium tetraboride to form magnesium diboride. With spherical magnesium powder an equiaxed microstructure of magnesium diboride is formed with residual magnesium tetraboride at the grain boundaries. With plate-like magnesium powders elongated magnesium diboride grains are formed. In this case, residual magnesium tetraboride is found to agglomerate.

Analysis of Kelvin Probe operational models with application to SR-POEM

International Nuclear Information System (INIS)

Popescu, Eugeniu M

2011-01-01

We present a study of several models on which Kelvin Probe (KP) instruments with flat and spherical tips rely for operation and for the determination of the contact potential difference (CPD). The study is part of the development of a high-performance KP instrument that will be used in investigations of the patch effect for the sounding rocket principle of equivalence measurement experiment. Using covariance analysis for each model we investigate its performance as imposed by the Cramer-Rao bounds and the biases introduced in the estimation of the CPD, as well as its applicability to instrument control. (papers)

Collision-Induced Infrared Absorption by Collisional Complexes in Dense Hydrogen-Helium Gas Mixtures at Thousands of Kelvin

Science.gov (United States)

Abel, Martin; Frommhold, Lothar; Li, Xiaoping; Hunt, Katharine L. C.

2011-06-01

The interaction-induced absorption by collisional pairs of H{_2} molecules is an important opacity source in the atmospheres of the outer planets and cool stars. The emission spectra of cool white dwarf stars differ significantly in the infrared from the expected blackbody spectra of their cores, which is largely due to absorption by collisional H{_2}-H{_2}, H{_2}-He, and H{_2}-H complexes in the stellar atmospheres. Using quantum-chemical methods we compute the atmospheric absorption from hundreds to thousands of kelvin. Laboratory measurements of interaction-induced absorption spectra by H{_2} pairs exist only at room temperature and below. We show that our results reproduce these measurements closely, so that our computational data permit reliable modeling of stellar atmosphere opacities even for the higher temperatures. L. Frommhold, Collision-Induced Absorption in Gases, Cambridge University Press, Cambridge, New York, 1993 and 2006 Xiaoping Li, Katharine L. C. Hunt, Fei Wang, Martin Abel, and Lothar Frommhold, "Collision-Induced Infrared Absorption by Molecular Hydrogen Pairs at Thousands of Kelvin", International Journal of Spectroscopy, vol. 2010, Article ID 371201, 11 pages, 2010. doi: 10.1155/2010/371201 M. Abel, L. Frommhold, X. Li, and K. L. C. Hunt, "Collision-induced absorption by H{_2} pairs: From hundreds to thousands of Kelvin," J. Phys. Chem. A, published online, DOI: 10.1021/jp109441f L. Frommhold, M. Abel, F. Wang, M. Gustafsson, X. Li, and K. L. C. Hunt, "Infrared atmospheric emission and absorption by simple molecular complexes, from first principles", Mol. Phys. 108, 2265, 2010

Observations of Confinement of a Paramagnetic Liquid in Model Propellant Tanks in Microgravity by the Kelvin Force

Science.gov (United States)

Kuhlman, John; Gray, Donald D.; Barnard, Austin; Hazelton, Jennifer; Lechliter, Matthew; Starn, Andrew; Battleson, Charles; Glaspell, Shannon; Kreitzer, Paul; Leichliter, Michelle

2002-11-01

The magnetic Kelvin force has been proposed as an artificial gravity to control the orientation of paramagnetic liquid propellants such as liquid oxygen in a microgravity environment. This paper reports experiments performed in the NASA "Weightless Wonder" KC-135 aircraft, through the Reduced Gravity Student Flight Opportunities Program. The aircraft flies through a series of parabolic arcs providing about 25 s of microgravity in each arc. The experiment was conceived, designed, constructed, and performed by the undergraduate student team and their two faculty advisors. Two types of tanks were tested: square-base prismatic tanks 5 cm x 5 cm x 8.6 cm and circular cylinders 5 cm in diameter and 8.6 cm tall. The paramagnetic liquid was a 3.3 molar solution of MnCl2 in water. Tests were performed with each type of tank filled to depths of 1 cm and 4 cm. Each test compared a pair of tanks that were identical except that the base of one was a pole face of a 0.6 Tesla permanent magnet. The Kelvin force attracts paramagnetic materials toward regions of higher magnetic field. It was hypothesized that the Kelvin force would hold the liquid in the bottom of the tanks during the periods of microgravity. The tanks were installed in a housing that could slide on rails transverse to the flight direction. By manually shoving the housing, an identical impulse could be provided to each tank at the beginning of each period of microgravity. The resulting fluid motions were videotaped for later analysis.

Design Enhancements of the Fourier Kelvin Stellar Interferometer to Enable Detection of Earth Twins

Science.gov (United States)

Barry, Richard K.; Danchi, William C.; Lopez, Bruno; Rinehart, Stephan; Augereau, Jean-Charles; Beust, Herve; Bonfils, Xavier; Borde, Pascal; Kern, Pierre; Leger, Alain;

Kelvin-Helmholtz instability: the ``atom'' of geophysical turbulence?

Science.gov (United States)

Smyth, William

2017-11-01

Observations of small-scale turbulence in Earth's atmosphere and oceans have most commonly been interpreted in terms of the Kolmogorov theory of isotropic turbulence, despite the fact that the observed turbulence is significantly anisotropic due to density stratification and sheared large-scale flows. I will describe an alternative picture in which turbulence consists of distinct events that occur sporadically in space and time. The simplest model for an individual event is the ``Kelvin-Helmholtz (KH) ansatz'', in which turbulence relieves the dynamic instability of a localized shear layer. I will summarize evidence that the KH ansatz is a valid description of observed turbulence events, using microstructure measurements from the equatorial Pacific ocean as an example. While the KH ansatz has been under study for many decades and is reasonably well understood, the bigger picture is much less clear. How are the KH events distributed in space and time? How do different events interact with each other? I will describe some tentative steps toward a more thorough understanding.

Note: Switching crosstalk on and off in Kelvin probe force microscopy

International Nuclear Information System (INIS)

Polak, Leo; Wijngaarden, Rinke J.; Man, Sven de

2014-01-01

In Kelvin Probe Force Microscopy (KPFM) electronic crosstalk can occur between the excitation signal and probe deflection signal. Here, we demonstrate how a small modification to our commercial instrument enables us to literally switch the crosstalk on and off. We study in detail the effect of crosstalk on open-loop KPFM and compare with closed-loop KPFM. We measure the pure crosstalk signal and verify that we can correct for it in the data-processing required for open-loop KPFM. We also demonstrate that open-loop KPFM results are independent of the frequency and amplitude of the excitation signal, provided that the influence of crosstalk has been eliminated

Ten essential skills for electrical engineers

CERN Document Server

Dorr, Barry

2014-01-01

Engineers know that, as in any other discipline, getting a good job requires practical, up-to-date skills. An engineering degree provides a broad set of fundamentals. Ten Essential Skills applies those fundamentals to practical tasks required by employers. Written in a user-friendly, no-nonsense format, the book reviews practical skills using the latest tools and techniques, and features a companion website with interview practice problems and advanced material for readers wishing to pursue additional skills. With this book, aspiring and current engineers may approach job interviews confident

Kelvin probe force microscopy studies of the charge effects upon adsorption of carbon nanotubes and C60 fullerenes on hydrogen-terminated diamond

Science.gov (United States)

Kölsch, S.; Fritz, F.; Fenner, M. A.; Kurch, S.; Wöhrl, N.; Mayne, A. J.; Dujardin, G.; Meyer, C.

2018-01-01

Hydrogen-terminated diamond is known for its unusually high surface conductivity that is ascribed to its negative electron affinity. In the presence of acceptor molecules, electrons are expected to transfer from the surface to the acceptor, resulting in p-type surface conductivity. Here, we present Kelvin probe force microscopy (KPFM) measurements on carbon nanotubes and C60 adsorbed onto a hydrogen-terminated diamond(001) surface. A clear reduction in the Kelvin signal is observed at the position of the carbon nanotubes and C60 molecules as compared with the bare, air-exposed surface. This result can be explained by the high positive electron affinity of carbon nanotubes and C60, resulting in electron transfer from the surface to the adsorbates. When an oxygen-terminated diamond(001) is used instead, no reduction in the Kelvin signal is obtained. While the presence of a charged adsorbate or a difference in work function could induce a change in the KPFM signal, a charge transfer effect of the hydrogen-terminated diamond surface, by the adsorption of the carbon nanotubes and the C60 fullerenes, is consistent with previous theoretical studies.

Kelvin-Helmholtz instability and kinetic internal kink modes in tokamaks

International Nuclear Information System (INIS)

Naitou, H.

2002-01-01

The m=1 and n=1 kinetic internal kink (KIK) mode with a nonuniform density profile is studied by the cylindrical version of the gyro-reduced-MHD code which is one of the extended MHD codes being able to treat the physics beyond resistive MHD. Electron inertia and electron finite temperature effects are crucial. The linear mode structure of KIK mode includes the sheared poloidal flow with m=1, which excites the vortexes due to the Kelvin-Helmholtz (K-H) instability. We have found that there is a strong coupling between the KIK mode and the K-H mode even in the early nonlinear stage of KIK instability in which the width of the m=1 magnetic island is sufficiently small. (author)

Photoassisted Kelvin probe force microscopy at GaN surfaces: The role of polarity

Science.gov (United States)

Wei, J. D.; Li, S. F.; Atamuratov, A.; Wehmann, H.-H.; Waag, A.

2010-10-01

The behavior of GaN surfaces during photoassisted Kelvin probe force microscopy is demonstrated to be strongly dependant on surface polarity. The surface photovoltage of GaN surfaces illuminated with above-band gap light is analyzed as a function of time and light intensity. Distinct differences between Ga-polar and N-polar surfaces could be identified, attributed to photoinduced chemisorption of oxygen during illumination. These differences can be used for a contactless, nondestructive, and easy-performable analysis of the polarity of GaN surfaces.

KELVIN-HELMHOLTZ INSTABILITY OF A CORONAL STREAMER

Energy Technology Data Exchange (ETDEWEB)

Feng, L.; Gan, W. Q. [Key Laboratory of Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Sciences, 210008 Nanjing (China); Inhester, B., E-mail: lfeng@pmo.ac.cn [Max-Planck-Institut fuer Sonnensystemforschung, Max-Planck-Str.2, D-37191 Katlenburg-Lindau (Germany)

2013-09-10

Shear-flow-driven instability can play an important role in energy transfer processes in coronal plasma. We present for the first time the observation of a kink-like oscillation of a streamer that is probably caused by the streaming kink-mode Kelvin-Helmholtz instability (KHI). The wave-like behavior of the streamer was observed by the Large Angle and Spectrometric Coronagraph Experiment C2 and C3 on board the SOlar and Heliospheric Observatory. The observed wave had a period of about 70-80 minutes, and its wavelength increased from 2 R{sub Sun} to 3 R{sub Sun} in about 1.5 hr. The phase speeds of its crests and troughs decreased from 406 {+-} 20 to 356 {+-} 31 km s{sup -1} during the event. Within the same heliocentric range, the wave amplitude also appeared to increase with time. We attribute the phenomena to the MHD KHI, which occurs at a neutral sheet in a fluid wake. The free energy driving the instability is supplied by the sheared flow and sheared magnetic field across the streamer plane. The plasma properties of the local environment of the streamer were estimated from the phase speed and instability threshold criteria.

Million-degree plasma pervading the extended Orion Nebula.

Science.gov (United States)

Güdel, Manuel; Briggs, Kevin R; Montmerle, Thierry; Audard, Marc; Rebull, Luisa; Skinner, Stephen L

2008-01-18

Most stars form as members of large associations within dense, very cold (10 to 100 kelvin) molecular clouds. The nearby giant molecular cloud in Orion hosts several thousand stars of ages less than a few million years, many of which are located in or around the famous Orion Nebula, a prominent gas structure illuminated and ionized by a small group of massive stars (the Trapezium). We present x-ray observations obtained with the X-ray Multi-Mirror satellite XMM-Newton, revealing that a hot plasma with a temperature of 1.7 to 2.1 million kelvin pervades the southwest extension of the nebula. The plasma flows into the adjacent interstellar medium. This x-ray outflow phenomenon must be widespread throughout our Galaxy.

Dual harmonic Kelvin probe force microscopy at the graphene–liquid interface

International Nuclear Information System (INIS)

Collins, Liam; Rodriguez, Brian J.; Kilpatrick, Jason I.; Weber, Stefan A. L.; Vlassiouk, Ivan V.; Tselev, Alexander; Jesse, Stephen; Kalinin, Sergei V.

2014-01-01

Kelvin probe force microscopy (KPFM) is a powerful technique for the determination of the contact potential difference (CPD) between an atomic force microscope tip and a sample under ambient and vacuum conditions. However, for many energy storage and conversion systems, including graphene-based electrochemical capacitors, understanding electrochemical phenomena at the solid–liquid interface is paramount. Despite the vast potential to provide fundamental insight for energy storage materials at the nanoscale, KPFM has found limited applicability in liquid environments to date. Here, using dual harmonic (DH)-KPFM, we demonstrate CPD imaging of graphene in liquid. We find good agreement with measurements performed in air, highlighting the potential of DH-KPFM to probe electrochemistry at the graphene–liquid interface

Nonlinear evolution of the magnetized Kelvin-Helmholtz instability: From fluid to kinetic modeling

Czech Academy of Sciences Publication Activity Database

Henri, P.; Cerri, S.S.; Califano, F.; Pegoraro, F.; Rossi, C.; Faganello, M.; Šebek, Ondřej; Trávníček, Pavel M.; Hellinger, Petr; Frederiksen, J. T.; Nordlund, A.; Markidis, S.; Keppens, R.; Lapenta, G.

2013-01-01

Roč. 20, č. 10 (2013), 102118/1-102118/13 ISSN 1070-664X R&D Projects: GA MŠk(CZ) 7E11053 EU Projects: European Commission(XE) 263340 - SWIFF Grant - others:European Commission(XE) HPC-EUROPA2 - No. 228398; EU(XE) RI-283493; NASA (US) NNX11A1164G Institutional support: RVO:67985815 ; RVO:68378289 Keywords : Kelvin-Helmholtz instability * plasma kinetic theory * plasma magnetohydrodynamics Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics; BL - Plasma and Gas Discharge Physics (UFA-U) Impact factor: 2.249, year: 2013

Calibrated work function mapping by Kelvin probe force microscopy

Science.gov (United States)

Fernández Garrillo, Pablo A.; Grévin, Benjamin; Chevalier, Nicolas; Borowik, Łukasz

2018-04-01

We propose and demonstrate the implementation of an alternative work function tip calibration procedure for Kelvin probe force microscopy under ultrahigh vacuum, using monocrystalline metallic materials with known crystallographic orientation as reference samples, instead of the often used highly oriented pyrolytic graphite calibration sample. The implementation of this protocol allows the acquisition of absolute and reproducible work function values, with an improved uncertainty with respect to unprepared highly oriented pyrolytic graphite-based protocols. The developed protocol allows the local investigation of absolute work function values over nanostructured samples and can be implemented in electronic structures and devices characterization as demonstrated over a nanostructured semiconductor sample presenting Al0.7Ga0.3As and GaAs layers with variable thickness. Additionally, using our protocol we find that the work function of annealed highly oriented pyrolytic graphite is equal to 4.6 ± 0.03 eV.

Contribution to reconstruction of third degree rectovestibular ...

African Journals Online (AJOL)

2015-02-05

Feb 5, 2015 ... Abstract. The study was conducted on ten mares suffering from third degree rectovestibular laceration. Four uterine washes were performed in all cases by using diluted betadine (mixing 5ml of betadine antiseptic solution in 1 liter of sterile saline) to control vaginal and uterine infections before surgery.

Methods for measurement of electron emission yield under low energy electron-irradiation by collector method and Kelvin probe method

Energy Technology Data Exchange (ETDEWEB)

Tondu, Thomas; Belhaj, Mohamed; Inguimbert, Virginie [Onera, DESP, 2 Avenue Edouard Belin, 31400 Toulouse (France); Onera, DESP, 2 Avenue Edouard Belin, 31400 Toulouse, France and Fondation STAE, 4 allee Emile Monso, BP 84234-31432, Toulouse Cedex 4 (France); Onera, DESP, 2 Avenue Edouard Belin, 31400 Toulouse (France)

2010-09-15

Secondary electron emission yield of gold under electron impact at normal incidence below 50 eV was investigated by the classical collector method and by the Kelvin probe method. The authors show that biasing a collector to ensure secondary electron collection while keeping the target grounded can lead to primary electron beam perturbations. Thus reliable secondary electron emission yield at low primary electron energy cannot be obtained with a biased collector. The authors present two collector-free methods based on current measurement and on electron pulse surface potential buildup (Kelvin probe method). These methods are consistent, but at very low energy, measurements become sensitive to the earth magnetic field (below 10 eV). For gold, the authors can extrapolate total emission yield at 0 eV to 0.5, while a total electron emission yield of 1 is obtained at 40{+-}1 eV.

Methods for measurement of electron emission yield under low energy electron-irradiation by collector method and Kelvin probe method

International Nuclear Information System (INIS)

Tondu, Thomas; Belhaj, Mohamed; Inguimbert, Virginie

2010-01-01

Secondary electron emission yield of gold under electron impact at normal incidence below 50 eV was investigated by the classical collector method and by the Kelvin probe method. The authors show that biasing a collector to ensure secondary electron collection while keeping the target grounded can lead to primary electron beam perturbations. Thus reliable secondary electron emission yield at low primary electron energy cannot be obtained with a biased collector. The authors present two collector-free methods based on current measurement and on electron pulse surface potential buildup (Kelvin probe method). These methods are consistent, but at very low energy, measurements become sensitive to the earth magnetic field (below 10 eV). For gold, the authors can extrapolate total emission yield at 0 eV to 0.5, while a total electron emission yield of 1 is obtained at 40±1 eV.

Kelvin wave coupling from TIMED and GOCE: Inter/intra-annual variability and solar activity effects

Science.gov (United States)

Gasperini, Federico; Forbes, Jeffrey M.; Doornbos, Eelco N.; Bruinsma, Sean L.

2018-06-01

The primary mechanism through which energy and momentum are transferred from the lower atmosphere to the thermosphere is through the generation and propagation of atmospheric waves. It is becoming increasingly evident that a few waves from the tropical wave spectrum preferentially propagate into the thermosphere and contribute to modify satellite drag. Two of the more prominent and well-established tropical waves are Kelvin waves: the eastward-propagating 3-day ultra-fast Kelvin wave (UFKW) and the eastward-propagating diurnal tide with zonal wave number 3 (DE3). In this work, Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) temperatures at 110 km and Gravity field and steady-state Ocean Circulation Explorer (GOCE) neutral densities and cross-track winds near 260 km are used to demonstrate vertical coupling in this height regime due to the UFKW and DE3. Significant inter- and intra-annual variability is found in DE3 and the UFKW, with evidence of latitudinal broadening and filtering of the latitude structures with height due to the effect of dissipation and mean winds. Additionally, anti-correlation between the vertical penetration of these waves to the middle thermosphere and solar activity level is established and explained through the effect of molecular dissipation.

Kelvin-Helmholtz instability in a bounded plasma flow

International Nuclear Information System (INIS)

Burinskaya, T. M.

2008-01-01

Kelvin-Helmholtz instability in a three-layer plane geometry is investigated theoretically. It is shown that, in a three-layer system (in contrast to the traditionally considered case in which instability develops at the boundary between two plasma flows), instability can develop at an arbitrary ratio of the plasma flow velocity to the ion-acoustic velocity. Perturbations with wavelengths on the order of the flow thickness or longer can increase even at a zero temperature. The system can also be unstable against long-wavelength perturbations if the flow velocity at one of the boundaries is lower than the sum of the Alfven velocities in the flow and the ambient plasma. The possibility of applying the results obtained to interpret the experimental data acquired in the framework of the CLUSTER multisatellite project is discussed. It follows from these data that, in many cases, the propagation of an accelerated particle flow in the plasma-sheet boundary layer of the Earth's magnetotail is accompanied by the generation of magnetic field oscillations propagating with a velocity on the order of the local Alfven velocity.

Successful replantation in ten-digit amputation.

Science.gov (United States)

Kantarci, Umit; Cepel, Selim; Buldu, Halil

2010-01-01

Amputations involving ten digits are very rare because of different lengths of the digits. A 34-year-old man working in a printing house presented one hour after guillotine amputation involving all ten digits. Surgery was initiated 80 minutes after admission and took seven hours. Under axillary anesthesia, the operation was performed by two teams each consisting of two microsurgeons and two assistants. Replantation was completed without the use of any skin graft or flap. Fingertip examination showed poor arterial circulation in the second, third, and fourth digits of the left hand after 24 hours of replantation and surgical exploration was performed, during which anastomosis of the ulnar digital artery of the second digit was re-established and a Y-shaped vein graft was placed at the level of the third web to restore revascularization of the third and fourth digits. However, these interventions did not prevent the development of necrosis in the distal segment of the fourth digit which resulted in dry gangrene that required amputation. After 38 months of replantation, radiographic examination showed complete union in all fingers without malunion or damage to the joint surface and about 8 degrees of medial angulation in the proximal phalanx of the fourth digit of the right hand. The patient did not have difficulty in performing daily activities and had a considerably good pinching. Losses of active range of motion of the metacarpophalangeal and interphalangeal joints were within the rage of 10 to 30 degrees in both hands. In the assessment of sensation, static and dynamic two-point discrimination test results were 6.1 mm and 4.0 mm, respectively.

Business Administration and Computer Science Degrees: Earnings, Job Security, and Job Satisfaction

Science.gov (United States)

Mehta, Kamlesh; Uhlig, Ronald

2017-01-01

This paper examines the potential of business administration vs. computer science degrees in terms of earnings, job security, and job satisfaction. The paper focuses on earnings potential five years and ten years after the completion of business administration and computer science degrees. Moreover, the paper presents the income changes with…

Stochastic volatility models and Kelvin waves

Science.gov (United States)

Lipton, Alex; Sepp, Artur

2008-08-01

We use stochastic volatility models to describe the evolution of an asset price, its instantaneous volatility and its realized volatility. In particular, we concentrate on the Stein and Stein model (SSM) (1991) for the stochastic asset volatility and the Heston model (HM) (1993) for the stochastic asset variance. By construction, the volatility is not sign definite in SSM and is non-negative in HM. It is well known that both models produce closed-form expressions for the prices of vanilla option via the Lewis-Lipton formula. However, the numerical pricing of exotic options by means of the finite difference and Monte Carlo methods is much more complex for HM than for SSM. Until now, this complexity was considered to be an acceptable price to pay for ensuring that the asset volatility is non-negative. We argue that having negative stochastic volatility is a psychological rather than financial or mathematical problem, and advocate using SSM rather than HM in most applications. We extend SSM by adding volatility jumps and obtain a closed-form expression for the density of the asset price and its realized volatility. We also show that the current method of choice for solving pricing problems with stochastic volatility (via the affine ansatz for the Fourier-transformed density function) can be traced back to the Kelvin method designed in the 19th century for studying wave motion problems arising in fluid dynamics.

Stochastic volatility models and Kelvin waves

International Nuclear Information System (INIS)

Lipton, Alex; Sepp, Artur

2008-01-01

We use stochastic volatility models to describe the evolution of an asset price, its instantaneous volatility and its realized volatility. In particular, we concentrate on the Stein and Stein model (SSM) (1991) for the stochastic asset volatility and the Heston model (HM) (1993) for the stochastic asset variance. By construction, the volatility is not sign definite in SSM and is non-negative in HM. It is well known that both models produce closed-form expressions for the prices of vanilla option via the Lewis-Lipton formula. However, the numerical pricing of exotic options by means of the finite difference and Monte Carlo methods is much more complex for HM than for SSM. Until now, this complexity was considered to be an acceptable price to pay for ensuring that the asset volatility is non-negative. We argue that having negative stochastic volatility is a psychological rather than financial or mathematical problem, and advocate using SSM rather than HM in most applications. We extend SSM by adding volatility jumps and obtain a closed-form expression for the density of the asset price and its realized volatility. We also show that the current method of choice for solving pricing problems with stochastic volatility (via the affine ansatz for the Fourier-transformed density function) can be traced back to the Kelvin method designed in the 19th century for studying wave motion problems arising in fluid dynamics

Stochastic volatility models and Kelvin waves

Energy Technology Data Exchange (ETDEWEB)

Lipton, Alex [Merrill Lynch, Mlfc Main, 2 King Edward Street, London EC1A 1HQ (United Kingdom); Sepp, Artur [Merrill Lynch, 4 World Financial Center, New York, NY 10080 (United States)], E-mail: Alex_Lipton@ml.com, E-mail: Artur_Sepp@ml.com

2008-08-29

We use stochastic volatility models to describe the evolution of an asset price, its instantaneous volatility and its realized volatility. In particular, we concentrate on the Stein and Stein model (SSM) (1991) for the stochastic asset volatility and the Heston model (HM) (1993) for the stochastic asset variance. By construction, the volatility is not sign definite in SSM and is non-negative in HM. It is well known that both models produce closed-form expressions for the prices of vanilla option via the Lewis-Lipton formula. However, the numerical pricing of exotic options by means of the finite difference and Monte Carlo methods is much more complex for HM than for SSM. Until now, this complexity was considered to be an acceptable price to pay for ensuring that the asset volatility is non-negative. We argue that having negative stochastic volatility is a psychological rather than financial or mathematical problem, and advocate using SSM rather than HM in most applications. We extend SSM by adding volatility jumps and obtain a closed-form expression for the density of the asset price and its realized volatility. We also show that the current method of choice for solving pricing problems with stochastic volatility (via the affine ansatz for the Fourier-transformed density function) can be traced back to the Kelvin method designed in the 19th century for studying wave motion problems arising in fluid dynamics.

Decay of MHD-scale Kelvin-Helmholtz vortices mediated by parasitic electron dynamics

International Nuclear Information System (INIS)

Nakamura, T.K.M.; Hayashi, D.; Fujimoto, M.; Shinohara, I.

2004-01-01

We have simulated nonlinear development of MHD-scale Kelvin-Helmholtz (KH) vortices by a two-dimensional two-fluid system including finite electron inertial effects. In the presence of moderate density jump across a shear layer, in striking contrast to MHD results, MHD KH vortices are found to decay by the time one eddy turnover is completed. The decay is mediated by smaller vortices that appear within the parent vortex and stays effective even when the shear layer width is made larger. It is shown that the smaller vortices are basically of MHD nature while the seeding for these is achieved by the electron inertial effect. Application of the results to the magnetotail boundary layer is discussed

Diffusion at the Earth magnetopause: enhancement by Kelvin-Helmholtz instability

Directory of Open Access Journals (Sweden)

R. Smets

2007-02-01

Full Text Available Using hybrid simulations, we examine how particles can diffuse across the Earth's magnetopause because of finite Larmor radius effects. We focus on tangential discontinuities and consider a reversal of the magnetic field that closely models the magnetopause under southward interplanetary magnetic field. When the Larmor radius is on the order of the field reversal thickness, we show that particles can cross the discontinuity. We also show that with a realistic initial shear flow, a Kelvin-Helmholtz instability develops that increases the efficiency of the crossing process. We investigate the distribution functions of the transmitted ions and demonstrate that they are structured according to a D-shape. It accordingly appears that magnetic reconnection at the magnetopause is not the only process that leads to such specific distribution functions. A simple analytical model that describes the built-up of these functions is proposed.

Vector electric field measurement via position-modulated Kelvin probe force microscopy

Science.gov (United States)

Dwyer, Ryan P.; Smieska, Louisa M.; Tirmzi, Ali Moeed; Marohn, John A.

2017-10-01

High-quality spatially resolved measurements of electric fields are critical to understanding charge injection, charge transport, and charge trapping in semiconducting materials. Here, we report a variation of frequency-modulated Kelvin probe force microscopy that enables spatially resolved measurements of the electric field. We measure electric field components along multiple directions simultaneously by employing position modulation and lock-in detection in addition to numeric differentiation of the surface potential. We demonstrate the technique by recording linescans of the in-plane electric field vector in the vicinity of a patch of trapped charge in a 2,7-diphenyl[1]benzothieno[3,2-b][1]benzothiophene (DPh-BTBT) organic field-effect transistor. This technique is simple to implement and should be especially useful for studying electric fields in spatially inhomogeneous samples like organic transistors and photovoltaic blends.

Measuring minority-carrier diffusion length using a Kelvin probe force microscope

International Nuclear Information System (INIS)

Shikler, R.; Fried, N.; Meoded, T.; Rosenwaks, Y.

2000-01-01

A method based on Kelvin probe force microscopy for measuring minority-carrier diffusion length in semiconductors is described. The method is based on measuring the surface photovoltage between the tip of an atomic force microscope and the surface of an illuminated semiconductor junction. The photogenerated carriers diffuse to the junction and change the contact potential difference between the tip and the sample, as a function of the distance from the junction. The diffusion length L is then obtained by fitting the measured contact potential difference using the minority-carrier continuity equation. The method was applied to measurements of electron diffusion length in GaP pn and Schottky junctions. The measured diffusion length was found to be ∼2 μm, in good agreement with electron beam induced current measurements

Magnetohydrodynamic Kelvin-Helmholtz instabilities in astrophysics. 4. Single shear layer in MHD flows

Energy Technology Data Exchange (ETDEWEB)

Ferrari, A [Consiglio Nazionale delle Ricerche, Turin (Italy). Lab. di Cosmo-Geofisica; Turin Univ. (Italy). Ist. di Fisica Generale); Trussoni, E [Consiglio Nazionale delle Ricerche, Turin (Italy). Lab. di Cosmo-Geofisica; Max-Planck-Institut fuer Physik und Astrophysik, Garching (Germany, F.R.). Inst. fuer Extraterrestrische Physik)

1983-11-01

In this further paper on the physics of Kelvin-Helmholtz instabilities the case in which the fluids in relative motion are magnetized and separated by a shear layer is investigated. The present study points out, with respect to previous treatments, that different velocity profiles affect perturbations of short wavelength (as compared to the scale of the shear). Another new result is in the destabilizing effect, even in the subsonic regime, of the magnetic field on modes neutrally stable in the vortex sheet approximation. Such a behaviour is analogous to that found in the fluid case for Mach numbers >approx. = to 2. Possible astrophysical implications are also discussed.

Magnetohydrodynamic Kelvin-Helmholtz instabilities in astrophysics. 1. Relativistic flows-plane boundary layer in vortex sheet approximation

Energy Technology Data Exchange (ETDEWEB)

Ferrari, A; Trussoni, E; Zaninetti, L [Consiglio Nazionale delle Ricerche, Turin (Italy). Lab. di Cosmo-Geofisica; Turin Univ. (Italy). Ist. di Fisica)

1980-11-01

In this paper some unsolved problems of the linear MHD Kelvin-Helmholtz instability are re-examined, starting from the analysis of relativistic (and non-relativistic) flows in the approximation of a plane vortex sheet, for the contact layer between the fluids in relative motion. Results are discussed for a range of physical parameters in specific connection with application to models of jets in extragalactic radio sources. Other physical aspects of the instability will be considered in forthcoming papers.

Work function of few layer graphene covered nickel thin films measured with Kelvin probe force microscopy

Energy Technology Data Exchange (ETDEWEB)

Eren, B. [Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland); Material Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720 (United States); Gysin, U.; Marot, L., E-mail: Laurent.marot@unibas.ch; Glatzel, Th.; Steiner, R.; Meyer, E. [Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland)

2016-01-25

Few layer graphene and graphite are simultaneously grown on a ∼100 nm thick polycrystalline nickel film. The work function of few layer graphene/Ni is found to be 4.15 eV with a variation of 50 meV by local measurements with Kelvin probe force microscopy. This value is lower than the work function of free standing graphene due to peculiar electronic structure resulting from metal 3d-carbon 2p(π) hybridization.

From cosmic chirality to protein structure: Lord Kelvin's legacy.

Science.gov (United States)

Barron, Laurence D

2012-11-01

A selection of my work on chirality is sketched in two distinct parts of this lecture. Symmetry and Chirality explains how the discrete symmetries of parity P, time reversal T, and charge conjugation C may be used to characterize the properties of chiral systems. The concepts of true chirality (time-invariant enantiomorphism) and false chirality (time-noninvariant enantiomorphism) that emerge provide an extension of Lord Kelvin's original definition of chirality to situations where motion is an essential ingredient thereby clarifying, inter alia, the nature of physical influences able to induce absolute enantioselection. Consideration of symmetry violations reveals that strict enantiomers (exactly degenerate) are interconverted by the combined CP operation. Raman optical activity surveys work, from first observation to current applications, on a new chiroptical spectroscopy that measures vibrational optical activity via Raman scattering of circularly polarized light. Raman optical activity provides incisive information ranging from absolute configuration and complete solution structure of smaller chiral molecules and oligomers to protein and nucleic acid structure of intact viruses. Copyright © 2012 Wiley Periodicals, Inc., A Wiley Company.

Infrared Spectra and Band Strengths of CH3SH, an Interstellar Molecule

Science.gov (United States)

Hudson, R. L.

2016-01-01

Three solid phases of CH3SH (methanethiol or methyl mercaptan) have been prepared and their mid-infrared spectra recorded at 10-110 degrees Kelvin, with an emphasis on the 17-100 degrees Kelvin region. Refractive indices have been measured at two temperatures and used to estimate ice densities and infrared band strengths. Vapor pressures for the two crystalline phases of CH3SH at 110 degrees Kelvin are estimated. The behavior of amorphous CH3SH on warming is presented and discussed in terms of Ostwald's step rule. Comparisons to CH3OH under similar conditions are made, and some inconsistencies and ambiguities in the CH3SH literature are examined and corrected.

High spatial resolution Kelvin probe force microscopy with coaxial probes

International Nuclear Information System (INIS)

Brown, Keith A; Westervelt, Robert M; Satzinger, Kevin J

2012-01-01

Kelvin probe force microscopy (KPFM) is a widely used technique to measure the local contact potential difference (CPD) between an AFM probe and the sample surface via the electrostatic force. The spatial resolution of KPFM is intrinsically limited by the long range of the electrostatic interaction, which includes contributions from the macroscopic cantilever and the conical tip. Here, we present coaxial AFM probes in which the cantilever and cone are shielded by a conducting shell, confining the tip–sample electrostatic interaction to a small region near the end of the tip. We have developed a technique to measure the true CPD despite the presence of the shell electrode. We find that the behavior of these probes agrees with an electrostatic model of the force, and we observe a factor of five improvement in spatial resolution relative to unshielded probes. Our discussion centers on KPFM, but the field confinement offered by these probes may improve any variant of electrostatic force microscopy. (paper)

On Multiple Hall-Like Electron Currents and Tripolar Guide Magnetic Field Perturbations During Kelvin-Helmholtz Waves

Science.gov (United States)

Sturner, Andrew P.; Eriksson, Stefan; Nakamura, Takuma; Gershman, Daniel J.; Plaschke, Ferdinand; Ergun, Robert E.; Wilder, Frederick D.; Giles, Barbara; Pollock, Craig; Paterson, William R.; Strangeway, Robert J.; Baumjohann, Wolfgang; Burch, James L.

2018-02-01

Two magnetopause current sheet crossings with tripolar guide magnetic field signatures were observed by multiple Magnetosphere Multiscale (MMS) spacecraft during Kelvin-Helmholtz wave activity. The two out-of-plane magnetic field depressions of the tripolar guide magnetic field are largely supported by the observed in-plane electron currents, which are reminiscent of two clockwise Hall current loop systems. A comparison with a three-dimensional kinetic simulation of Kelvin-Helmholtz waves and vortex-induced reconnection suggests that MMS likely encountered the two Hall magnetic field depressions on either side of a magnetic reconnection X-line. Moreover, MMS observed an out-of-plane current reversal and a corresponding in-plane magnetic field rotation at the center of one of the current sheets, suggesting the presence of two adjacent flux ropes. The region inside one of the ion-scale flux ropes was characterized by an observed decrease of the total magnetic field, a strong axial current, and significant enhancements of electron density and parallel electron temperature. The flux rope boundary was characterized by currents opposite this axial current, strong in-plane and converging electric fields, parallel electric fields, and weak electron-frame Joule dissipation. These return current region observations may reflect a need to support the axial current rather than representing local reconnection signatures in the absence of any exhausts.

Using "Kaizen" to Improve Graduate Business School Degree Programs

Science.gov (United States)

Emiliani, M. L.

2005-01-01

Purpose: To illustrate the applicability of "kaizen" in higher education. Design/methodology/approach: "Kaizen" process was used for ten courses contained in a part-time executive MS degree program in management. Findings: "Kaizen" was found to be an effective process for improving graduate business school courses and the value proposition for…

MHD Kelvin-Helmholtz instability in non-hydrostatic equilibrium

International Nuclear Information System (INIS)

Laghouati, Y; Bouabdallah, A; Zizi, M; Alemany, A

2007-01-01

The present work deals with the linear stability of a magnetohydrodynamic shear flow so that a stratified inviscid fluid rotating about a vertical axis when a uniform magnetic field is applied in the direction of the streaming or zonal flow. In geophysical flow, the stability of the flow is determined by taking into account the nonhydrostatic condition depending on Richardson number R i and the deviation δ from hydrostatic equilibrium. According to Stone (Stone P H 1971 J. Fluid. Mech. 45 659), it is shown that such deviation δ decreases the growth rates of three kinds of instability which can appear as geostrophic (G), symmetric (S) and Kelvin-Helmholtz (K-H) instabilities. To be specific, the evolution of the flow is therefore considered in the light of the influence of magnetic field, particularly, on K-H instability. The results of this study are presented by the linear stability of a magnetohydrodynamic, with horizontal free-shear flow of stratified fluid, subject to rotation about the vertical axis and uniform magnetic field in the zonal direction. Results are discussed and compared to previous works as Chandrasekhar (Chandrasekhar S 1961 Hydrodynamic and hydromagnetic stability (Oxford: Clarendon Press) chapter 11 pp 481-513) and Stone

Interactions between two magnetohydrodynamic Kelvin-Helmholtz instabilities

International Nuclear Information System (INIS)

Lai, S. H.; Ip, W.-H.

2011-01-01

Kelvin-Helmholtz instability (KHI) driven by velocity shear is a generator of waves found away from the vicinity of the velocity-shear layers since the fast-mode waves radiated from the surface perturbation can propagate away from the transition layer. Thus the nonlinear evolution associated with KHI is not confined near the velocity-shear layer. To understand the physical processes in multiple velocity-shear layers, the interactions between two KHIs at a pair of tangential discontinuities are studied by two-dimensional magnetohydrodynamic simulations. It is shown that the interactions between two neighboring velocity-shear layers are dominated by the propagation of the fast-mode waves radiated from KHIs in a nonuniform medium. That is, the fast-mode Mach number of the surface waves M Fy , a key factor of the nonlinear evolution of KHI, will vary with the nonuniform background plasma velocity due to the existence of two neighboring velocity-shear layers. As long as the M Fy observed in the plasma rest frame across the neighboring velocity-shear layer is larger than one, newly formed fast-mode Mach-cone-like (MCL) plane waves generated by the fast-mode waves can be found in this region. As results of the interactions of two KHIs, reflection and distortion of the MCL plane waves generate the turbulence and increase the plasma temperature, which provide possible mechanisms of heating and accelerating local plasma between two neighboring velocity-shear layers.

Superconducting Mercury-Based Cuprate Films with a Zero-Resistance Transition Temperature of 124 Kelvin

Science.gov (United States)

Tsuei, C. C.; Gupta, A.; Trafas, G.; Mitzi, D.

1994-03-01

The synthesis of high-quality films of the recently discovered mercury-based cuprate films with high transition temperatures has been plagued by problems such as the air sensitivity of the cuprate precursor and the volatility of Hg and HgO. These processing difficulties have been circumvented by a technique of atomic-scale mixing of the HgO and cuprate precursors, use of a protective cap layer, and annealing in an appropriate Hg and O_2 environment. With this procedure, a zero-resistance transition temperature as high as 124 kelvin in c axis-oriented epitaxial HgBa_2CaCu_2O6+δ films has been achieved.

Superconducting mercury-based cuprate films with a zero-resistance transition temperature of 124 Kelvin.

Science.gov (United States)

Tsuei, C C; Gupta, A; Trafas, G; Mitzi, D

1994-03-04

The synthesis of high-quality films of the recently discovered mercury-based cuprate films with high transition temperatures has been plagued by problems such as the air sensitivity of the cuprate precursor and the volatility of Hg and HgO. These processing difficulties have been circumvented by a technique of atomic-scale mixing of the HgO and cuprate precursors, use of a protective cap layer, and annealing in an appropriate Hg and O(2) environment. With this procedure, a zero-resistance transition temperature as high as 124 kelvin in c axis-oriented epitaxial HgBa(2)CaCu(2)O(6+delta) films has been achieved.

Kelvin probe studies of cesium telluride photocathode for AWA photoinjector

Energy Technology Data Exchange (ETDEWEB)

Wisniewski, Eric E., E-mail: ewisniew@anl.gov [High Energy Physics Division, Argonne National Laboratory, 9700 S. Cass, Lemont, IL 60439 (United States); Physics Department, Illinois Institute of Technology, 3300 South Federal Street, Chicago, IL 60616 (United States); Velazquez, Daniel [High Energy Physics Division, Argonne National Laboratory, 9700 S. Cass, Lemont, IL 60439 (United States); Physics Department, Illinois Institute of Technology, 3300 South Federal Street, Chicago, IL 60616 (United States); Yusof, Zikri, E-mail: zyusof@hawk.iit.edu [High Energy Physics Division, Argonne National Laboratory, 9700 S. Cass, Lemont, IL 60439 (United States); Physics Department, Illinois Institute of Technology, 3300 South Federal Street, Chicago, IL 60616 (United States); Spentzouris, Linda; Terry, Jeff [Physics Department, Illinois Institute of Technology, 3300 South Federal Street, Chicago, IL 60616 (United States); Sarkar, Tapash J. [Rice University, 6100 Main, Houston, TX 77005 (United States); Harkay, Katherine [Accelerator Science Division, Argonne National Laboratory, 9700 S. Cass, Lemont, IL 60439 (United States)

2013-05-21

Cesium telluride is an important photocathode as an electron source for particle accelerators. It has a relatively high quantum efficiency (>1%), is sufficiently robust in a photoinjector, and has a long lifetime. This photocathode is grown in-house for a new Argonne Wakefield Accelerator (AWA) beamline to produce high charge per bunch (≈50nC) in a long bunch train. Here, we present a study of the work function of cesium telluride photocathode using the Kelvin probe technique. The study includes an investigation of the correlation between the quantum efficiency and the work function, the effect of photocathode aging, the effect of UV exposure on the work function, and the evolution of the work function during and after photocathode rejuvenation via heating. -- Highlights: ► The correlation between Quantum Efficiency (QE) and work function. ► How QE and work function evolve together. ► Rejuvenation of the photocathode via heating and the effect on work function. ► The effects on the work function due to exposure to UV light.

Clinical experience with TENS and TENS combined with nitrous oxide-oxygen. Report of 371 patients.

OpenAIRE

Quarnstrom, F. C.; Milgrom, P.

1989-01-01

Transcutaneous electrical nerve stimulation (TENS) alone or TENS combined with nitrous oxide-oxygen (N2O) was administered for restorative dentistry without local anesthesia to 371 adult patients. A total of 55% of TENS alone and 84% of TENS/N2O visits were rated successful. A total of 53% of TENS alone and 82% of TENS/N2O patients reported slight or no pain. In multivariable analyses, pain reports were related to the anesthesia technique and patient fear and unrelated to sex, race, age, toot...

Mean shear flows, zonal flows, and generalized Kelvin-Helmholtz modes in drift wave turbulence: A minimal model for L→H transition

International Nuclear Information System (INIS)

Kim, Eun-jin; Diamond, P.H.

2003-01-01

The dynamics of and an interplay among structures (mean shear flows, zonal flows, and generalized Kelvin-Helmholtz modes) are studied in drift wave turbulence. Mean shear flows are found to inhibit the nonlinear generation of zonal flows by weakening the coherent modulation response of the drift wave spectrum. Based on this result, a minimal model for the L→H (low- to high-confinement) transition is proposed, which involves the amplitude of drift waves, zonal flows, and the density gradient. A transition to quiescent H-mode sets in as the profile becomes sufficiently steep to completely damp out drift waves, following an oscillatory transition phase where zonal flows regulate drift wave turbulence. The different roles of mean flows and zonal flows are elucidated. Finally, the effect of poloidally nonaxisymmetric structures (generalized Kelvin-Helmholtz mode) on anomalous transport is investigated, especially in reference to damping of collisionless zonal flows. Results indicate that nonlinear excitation of this structure can be potentially important in enhancing anomalous transport as well as in damping zonal flows

The Fourier-Kelvin Stellar Interferometer (FKSI): Infrared Detection and Characterization of Exozodiacal Dust to Super-Earths, A Progress Report

Science.gov (United States)

Danchi, W.

2010-01-01

The Fourier-Kelvin Stellar Interferometer (FKSI) is a structurally connected infrared space interferometer with 0.5 m diameter telescopes on a 12.5 m baseline, and is passively cooled to approx.60K. The FKSI operates in the thermal infrared from 3-8 microns in a nulling (or starlight suppressing) mode for the detection and characterization of exoplanets, debris disks, extrasolar zodiacal dust levels. The FKSI will have the highest angular resolution of any infrared space instrument ever made with its nominal resolution of 40 mas at a 5 micron center wavelength. This resolution exceeds that of Spitzer by a factor of 38 and JWST by a factor of 5. The FKSI mission is conceived as a "probe class" or "mid-sized" strategic mission that utilizes technology advances from flagship projects like JWST, SIM, Spitzer, and the technology programs of TPF-I/Darwin. During the past year we began investigating an enhanced version of FKSI with 1-2 m diameter telescopes, passively cooled to 40K, on a 20-m baseline, with a sunshade giving a +/- 45 degree Field-of-Regard. This enhanced design is capable of detecting and characterizing the atmospheres of many 2 Earth-radius super-Earths and a few Earth-twins. We will report progress on the design of the enhanced mission concept and current status of the technologies needed for this mission.

Electron Debye scale Kelvin-Helmholtz instability: Electrostatic particle-in-cell simulations

International Nuclear Information System (INIS)

Lee, Sang-Yun; Lee, Ensang; Kim, Khan-Hyuk; Lee, Dong-Hun; Seon, Jongho; Jin, Ho

2015-01-01

In this paper, we investigated the electron Debye scale Kelvin-Helmholtz (KH) instability using two-dimensional electrostatic particle-in-cell simulations. We introduced a velocity shear layer with a thickness comparable to the electron Debye length and examined the generation of the KH instability. The KH instability occurs in a similar manner as observed in the KH instabilities in fluid or ion scales producing surface waves and rolled-up vortices. The strength and growth rate of the electron Debye scale KH instability is affected by the structure of the velocity shear layer. The strength depends on the magnitude of the velocity and the growth rate on the velocity gradient of the shear layer. However, the development of the electron Debye scale KH instability is mainly determined by the electric field generated by charge separation. Significant mixing of electrons occurs across the shear layer, and a fraction of electrons can penetrate deeply into the opposite side fairly far from the vortices across the shear layer

The ten thousand Kims

Science.gov (United States)

Baek, Seung Ki; Minnhagen, Petter; Kim, Beom Jun

2011-07-01

In Korean culture, the names of family members are recorded in special family books. This makes it possible to follow the distribution of Korean family names far back in history. It is shown here that these name distributions are well described by a simple null model, the random group formation (RGF) model. This model makes it possible to predict how the name distributions change and these predictions are shown to be borne out. In particular, the RGF model predicts that for married women entering a collection of family books in a certain year, the occurrence of the most common family name 'Kim' should be directly proportional to the total number of married women with the same proportionality constant for all the years. This prediction is also borne out to a high degree. We speculate that it reflects some inherent social stability in the Korean culture. In addition, we obtain an estimate of the total population of the Korean culture down to the year 500 AD, based on the RGF model, and find about ten thousand Kims.

The ten thousand Kims

International Nuclear Information System (INIS)

Baek, Seung Ki; Minnhagen, Petter; Kim, Beom Jun

2011-01-01

In Korean culture, the names of family members are recorded in special family books. This makes it possible to follow the distribution of Korean family names far back in history. It is shown here that these name distributions are well described by a simple null model, the random group formation (RGF) model. This model makes it possible to predict how the name distributions change and these predictions are shown to be borne out. In particular, the RGF model predicts that for married women entering a collection of family books in a certain year, the occurrence of the most common family name 'Kim' should be directly proportional to the total number of married women with the same proportionality constant for all the years. This prediction is also borne out to a high degree. We speculate that it reflects some inherent social stability in the Korean culture. In addition, we obtain an estimate of the total population of the Korean culture down to the year 500 AD, based on the RGF model, and find about ten thousand Kims.

Ten per cent polarized optical emission from GRB 090102.

Science.gov (United States)

Steele, I A; Mundell, C G; Smith, R J; Kobayashi, S; Guidorzi, C

2009-12-10

The nature of the jets and the role of magnetic fields in gamma-ray bursts (GRBs) remains unclear. In a baryon-dominated jet only weak, tangled fields generated in situ through shocks would be present. In an alternative model, jets are threaded with large-scale magnetic fields that originate at the central engine and that accelerate and collimate the material. To distinguish between the models the degree of polarization in early-time emission must be measured; however, previous claims of gamma-ray polarization have been controversial. Here we report that the early optical emission from GRB 090102 was polarized at 10 +/- 1 per cent, indicating the presence of large-scale fields originating in the expanding fireball. If the degree of polarization and its position angle were variable on timescales shorter than our 60-second exposure, then the peak polarization may have been larger than ten per cent.

Magnetohydrodynamic Kelvin-Helmholtz instabilities in astrophysics. 2. Cylindrical boundary layer in vortex sheet approximation

Energy Technology Data Exchange (ETDEWEB)

Ferrari, A [Max-Planck-Institut fuer Extraterrestrische Physik, Garching b. Muenchen (Germany, F.R.); Consiglio Nazionale delle Ricerche, Turin (Italy). Lab. di Cosmo-Geofisica); Trussoni, E; Zaninetti, L [Consiglio Nazionale delle Ricerche, Turin (Italy). Lab. di Cosmo-Geofisica

1981-09-01

This second paper of the series is devoted to Kelvin-Helmholtz instabilities in cylindrical boundary layer flows (jets). The vortex-sheet approximation is still used, and compressible flows are studied in subsonic, transonic, supersonic and relativistic regimes. Magnetic field effects are analysed, together with density contrast inside and outside the jet. The general result is that, due to the onset of a so-called reflection branch of resonant modes, jets are always unstable, both to pinching and helical perturbations with wavelengths of the order of the jet circumference. In particular the time-scales for instability are such that this certainly plays a significant part in the morphology and energetics of extended radio sources.

SPICA sub-Kelvin cryogenic chains

Science.gov (United States)

Duband, L.; Duval, J. M.; Luchier, N.; Prouve, T.

2012-04-01

the sorption cooler has extremely low mass for a sub-Kelvin cooler, it allows the stringent mass budget to be met. These concepts are discussed in this paper.

The importance of cantilever dynamics in the interpretation of Kelvin probe force microscopy.

Science.gov (United States)

Satzinger, Kevin J; Brown, Keith A; Westervelt, Robert M

2012-09-15

A realistic interpretation of the measured contact potential difference (CPD) in Kelvin probe force microscopy (KPFM) is crucial in order to extract meaningful information about the sample. Central to this interpretation is a method to include contributions from the macroscopic cantilever arm, as well as the cone and sharp tip of a KPFM probe. Here, three models of the electrostatic interaction between a KPFM probe and a sample are tested through an electrostatic simulation and compared with experiment. In contrast with previous studies that treat the KPFM cantilever as a rigid object, we allow the cantilever to bend and rotate; accounting for cantilever bending provides the closest agreement between theory and experiment. We demonstrate that cantilever dynamics play a major role in CPD measurements and provide a simulation technique to explore this phenomenon.

Reconstruction of propagating Kelvin-Helmholtz vortices at Mercury's magnetopause

Science.gov (United States)

Sundberg, Torbjörn; Boardsen, Scott A.; Slavin, James A.; Blomberg, Lars G.; Cumnock, Judy A.; Solomon, Sean C.; Anderson, Brian J.; Korth, Haje

2011-12-01

A series of quasi-periodic magnetopause crossings were recorded by the MESSENGER spacecraft during its third flyby of Mercury on 29 September 2009, likely caused by a train of propagating Kelvin-Helmholtz (KH) vortices. We here revisit the observations to study the internal structure of the waves. Exploiting MESSENGER's rapid traversal of the magnetopause, we show that the observations permit a reconstruction of the structure of a rolled-up KH vortex directly from the spacecraft's magnetic field measurements. The derived geometry is consistent with all large-scale fluctuations in the magnetic field data, establishes the non-linear nature of the waves, and shows their vortex-like structure. In several of the wave passages, a reduction in magnetic field strength is observed in the middle of the wave, which is characteristic of rolled-up vortices and is related to the increase in magnetic pressure required to balance the centrifugal force on the plasma in the outer regions of a vortex, previously reported in computer simulations. As the KH wave starts to roll up, the reconstructed geometry suggests that the vortices develop two gradual transition regions in the magnetic field, possibly related to the mixing of magnetosheath and magnetospheric plasma, situated at the leading edges from the perspectives of both the magnetosphere and the magnetosheath.

Kelvin-Helmholtz evolution in subsonic cold streams feeding galaxies

Science.gov (United States)

Angulo, Adrianna; Coffing, S.; Kuranz, C.; Drake, R. P.; Klein, S.; Trantham, M.; Malamud, G.

2017-10-01

The most prolific star formers in cosmological history lie in a regime where dense filament structures carried substantial mass into the galaxy to sustain star formation without producing a shock. However, hydrodynamic instabilities present on the filament surface limit the ability of such structures to deliver dense matter deeply enough to sustain star formation. Simulations lack the finite resolution necessary to allow fair treatment of the instabilities present at the stream boundary. Using the Omega EP laser, we simulate this mode of galaxy formation with a cold, dense, filament structure within a hotter, subsonic flow and observe the interface evolution. Machined surface perturbations stimulate the development of the Kelvin-Helmholtz (KH) instability due to the resultant shear between the two media. A spherical crystal imaging system produces high-resolution radiographs of the KH structures along the filament surface. The results from the first experiments of this kind, using a rod with single-mode, long-wavelength modulations, will be discussed. This work is funded by the U.S. Department of Energy, through the NNSA-DS and SC-OFES Joint Program in High-Energy-Density Laboratory Plasmas, Grant Number DE-NA0002956, and the National Laser User Facility Program, Grant Number DE-NA0002719, and through.

HIPs at Ten

Science.gov (United States)

Kuh, George; O'Donnell, Ken; Schneider, Carol Geary

2017-01-01

2017 is the anniversary of the introduction of what are now commonly known as high-impact practices (HIPs). Many of the specific activities pursued under the HIPs acronym have been around in some form for decades, such as study abroad, internships, and student-faculty research. It was about ten years ago that, after conferring HIPs at Ten with…

The pyrolysis of gas condensate at the Shatlyk field

Energy Technology Data Exchange (ETDEWEB)

Magaril, R.Z.; Khankuliyev, K.; Kul' zhayev, B.A.; Sergiyenko, S.R.

1984-01-01

The continuing growth in industrial demand for lower olefins for the manufacture of polymer materials has necessitated an expansion in the manufacture of ethylene. Gas condensate may serve as a source of ethylene manufacturing. The influence of the contact temperature and time in the pyrolysis of unseparated condensate from the Shatlyk field on the yield of lower olefins was investigated. It was discovered that the total yield of lower olefins (C2-C4) increases with an increase in the pyrolysis temperature, reaching a maximum of 63 to 67 percent by weight at a temperature of 1098 degrees Kelvin and contact time of .5 to .7 seconds, and at 1123 degrees Kelvin and .3 seconds, the maximum ethylene yield (40 percent) was obtained at 1123 degrees Kelvin, and at all previously noted temperatures with a contact time of .9 seconds.

Microstructure influence on corrosion behavior of a Fe–Cr–V–N tool alloy studied by SEM/EDS, scanning Kelvin force microscopy and electrochemical measurement

International Nuclear Information System (INIS)

Sababi, Majid; Ejnermark, Sebastian; Andersson, Jörgen; Claesson, Per M.; Pan, Jinshan

2013-01-01

Highlights: ► Localized corrosion of a new N-based tool alloy (Fe–Cr–V–N) has been studied. ► One-pass mode of scanning Kelvin force microscopy (KFM) was used in the study. ► The focus was on correlation between microstructure and localized corrosion. - Abstract: Microstructure influence on corrosion behavior of an N-based tool alloy (Fe–Cr–V–N) has been studied. Electron microscopy analysis showed two types of hard phases in the alloy. One-pass mode scanning Kelvin force microscopy (KFM) was used to investigate relative nobility of the hard phases. Volta potential mapping indicates higher nobility for the hard phases than the alloy matrix, and, the V- and N-rich particles exhibit the highest Volta potential. Post-polarization analysis by SEM revealed localized dissolution initiated in matrix regions adjacent to hard phase particles, and the boundary region surrounding the Cr- and Mo-rich particles is more prone to localized corrosion.

Double-reconnected magnetic structures driven by Kelvin-Helmholtz vortices at the Earth's magnetosphere

Science.gov (United States)

Faganello, Matteo; Borgogno, Dario; Califano, Francesco; Pegoraro, Francesco

2015-11-01

In an almost collisionless MagnetoHydrodynamic plasma in a relatively strong magnetic field, stresses can be conveyed far from the region where they are exerted e.g., through the propagation of Alfvèn waves. The forced dynamics of line-tied magnetic structures in solar and stellar coronae is a paradigmatic case. We investigate how this action at a distance develops from the equatorial region of the Kelvin-Helmholtz unstable flanks of the Earth's magnetosphere leading to the onset, at mid latitude in both hemispheres, of correlated double magnetic field line reconnection events that can allow the solar wind plasma to enter the Earth's magnetosphere. This mid-latitude double reconnection process, first investigated in, has been confirmed here by following a large set of individual field lines using a method similar to a Poincarè map.

Local charge trapping in Ge nanoclustersdetected by Kelvin probe force microscopy

Energy Technology Data Exchange (ETDEWEB)

Kondratenko, S.V., E-mail: kondr@univ.kiev.ua [Taras Shevchenko National University of Kyiv, 64/13 Volodymyrska Str., 01601, Kyiv (Ukraine); Lysenko, V.S. [Institute of Semiconductor Physics, 41 Prospect Nauki, 03028, Kyiv (Ukraine); Kozyrev, Yu. N. [O.O. Chuiko Institute of Surface Chemistry, 17 GeneralaNaumova Str. 03164, Kiev (Ukraine); Kratzer, M. [Institute of Physics, MontanuniversitätLeoben, Franz Josef Str. 18, A-8700, Leoben (Austria); Storozhuk, D.P.; Iliash, S.A. [Taras Shevchenko National University of Kyiv, 64/13 Volodymyrska Str., 01601, Kyiv (Ukraine); Czibula, C. [Institute of Physics, MontanuniversitätLeoben, Franz Josef Str. 18, A-8700, Leoben (Austria); Teichert, C., E-mail: teichert@unileoben.ac.at [Institute of Physics, MontanuniversitätLeoben, Franz Josef Str. 18, A-8700, Leoben (Austria)

2016-12-15

The understanding of local charge trapping on the nanoscale is crucial for the design of novel electronic devices and photodetectors based on SiGe nanoclusters (NCs). Here, the local spatial distribution of the surface potential of the Ge NCs was detected using Kelvin probe force microscopy (KPFM). Different surface potentials between Ge NCs and the wetting layer (WL) surface were detected at room temperature. Changes of the local contact potential differences (CPD) were studied after injection of electrons or holes into single Ge NCs on top of the Si layer using a conductive atomic force microscopy tip. The CPD image contrast was increased after electron injection by applying a forward bias to the n-tip/i-Ge NC/p-Si junction. Injecting holes into a single Ge NC was also accompanied by filling of two-dimensional states in the surrounding region, which is governed by leakage currents through WL or surface states and Coulomb charging effects. A long retention time of holes trapped by the Ge NC was found.

Use of Kelvin probe force microscopy for identification of CVD grown graphene flakes on copper foil

Science.gov (United States)

Kumar, Rakesh; Mehta, B. R.; Kanjilal, D.

2017-05-01

Graphene flakes have been grown by chemical vapour deposition (CVD) method on Cu foils. The obtained graphene flakes have been characterized by optical microscopy, field emission scanning electron microscopy, Kelvin probe force microscopy (KPFM) and Raman spectroscopy. The graphene flakes grown on Cu foil comprise mainly single layer graphene and confirm that the nucleation for graphene growth starts very quickly. Moreover, KPFM has been found to be a valuable technique to differentiate between covered and uncovered portion of Cu foil by graphene flakes deposited for shorter duration. The results show that KPFM can be a very useful technique in understanding the mechanism of graphene growth.

Microscopic investigation of InGaN/GaN heterostructure laser diode degradation using Kelvin probe force microscopy

International Nuclear Information System (INIS)

Lochthofen, A; Mertin, W; Bacher, G; Furitsch, M; Bruederl, G; Strauss, U; Haerle, V

2008-01-01

We report on Kelvin probe force microscopy (KPFM) measurements on fresh and artificially aged InGaN/GaN laser test structures. In the case of an unbiased laser diode, a comparison of the surface potential between a fresh and a stressed laser diode shows a pronounced modification of the laser facet due to the aging process. Performing KPFM measurements under forward bias, a correlation between the macroscopic I-V characteristics and the microscopic voltage drop across the heterostructure layer sequence is found. This clearly demonstrates the potential of KPFM for investigating InGaN/GaN laser diode degradation

Time-resolved opto-electronic properties of poly(3-hexylthiophene-2,5-dyil): fullerene heterostructures detected by Kelvin force microscopy

Czech Academy of Sciences Publication Activity Database

Čermák, Jan; Rezek, Bohuslav; Cimrová, Věra; Fejfar, Antonín; Purkrt, Adam; Vaněček, Milan; Kočka, Jan

2010-01-01

Roč. 519, č. 2 (2010), s. 836-840 ISSN 0040-6090 R&D Projects: GA ČR GD202/09/H041; GA MŠk(CZ) LC06040; GA AV ČR KAN400100701; GA MŠk LC510; GA MŠk(CZ) 1M06031 Institutional research plan: CEZ:AV0Z10100521; CEZ:AV0Z40500505 Keywords : photovoltaics * bulk-heterojunction * atomic force microscopy * Kelvin force microscopy Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.909, year: 2010

Granulocyte colony-stimulating factor in toxic epidermal necrolysis (TEN) and Chelsea & Westminster TEN management protocol [corrected].

Science.gov (United States)

de Sica-Chapman, A; Williams, G; Soni, N; Bunker, C B

2010-04-01

Toxic epidermal necrolysis (TEN) is a rare but life-threatening, allergic drug reaction. Skin blistering with epidermal and mucosal necrolysis with subsequent detachment from an inflamed underlying dermis is a hallmark of the condition. The pathogenesis of TEN is not well understood, accounting for controversies about its management and significant delay in initiating potentially beneficial therapy. There are no management protocols based on a robust evidence base. Prompt recognition of the diagnosis and consensus on early management initiatives are necessary in order to improve outcomes and survival in TEN. To date, TEN management has been directed at arresting the allergic reaction and treating the complications. We have identified a need for specific medical interventions to accelerate wound regeneration. This approach has not previously been adopted in the management of TEN. We observed that in two cases of severe TEN, dramatic re-epithelialization and recovery coincided with the introduction of granulocyte colony-stimulating factor (G-CSF) for neutropenia. We explain how addition of the G-CSF promotes recovery from TEN by enhanced bioregeneration of the damaged tissues through accelerated re-epithelialization. G-CSF has been used for severe neutropenia in TEN, but we recommend and explain why, as in our Chelsea and Westminster protocol, G-CSF should be considered in treating severe TEN irrespective of the severity of neutropenia.

Kelvin-Helmholtz instability and kinetic internal kink modes in tokamaks

International Nuclear Information System (INIS)

Naitou, H.; Kobayashi, T.; Yagi, M.; Matsumoto, T.; Tokuda, S.; Kishimoto, Y.

2003-01-01

The m=1 (poloidal mode number) and n=1 (toroidal mode number) kinetic internal kink (KIK) mode in the presence of a density gradient is studied with the cylindrical version of the gyro-reduced MHD code, which is one of the extended MHD codes being able to treat the physics beyond resistive MHD. Electron inertia and electron finite temperature effects are included. The unstable KIK mode is observed in the parameter range in which the linear theory predicts complete stabilization due to the electron diamagnetic effect. The electrostatic potential profile in the linear stage of the KIK instability has the sheared poloidal flow with the m=1 mode structure. The vortexes are generated due to the Kelvin-Helmholtz (K-H) instability. The KIK is stabilized when the vortexes are formed, but it is destabilized again as the vortexes diminish due to the charge neutralizing electron motion along the magnetic field. These phenomena are observed in the early nonlinear stage of the KIK instability in which the width of the m=1 magnetic island is sufficiently small compared with the radial extent of the vortexes. The strong coupling between the vortexes and the KIK instability can be one of the candidates explaining the sudden onset of the sawtooth crash. (author)

The radioactivity, the sun, the Earth and Kelvin's death. A difficult dialog between physicists and geologists

International Nuclear Information System (INIS)

Richet, P.

1996-01-01

The question of the age of the Earth has remained mythical for a long time. During the last quarter of the 19. century, this question was the center of a strong controversy initiated by a physicist, William Thomson, the future Lord Kelvin. During the beginning of the 20. century, the discoveries of Becquerel and Pierre and Marie Curie about radioactivity gave rise to a new generation of physicists who were able to propose radiometric estimations of the Earth's age to geologists. This digest paper describes the historical aspects of the discovery of radioactivity and of the first attempts for dating the Earth using radiometric techniques, and the strong discussions within the geologists community. (J.S.)

Kelvin-Helmholtz instability in type-1 comet tails and associated phenomena

International Nuclear Information System (INIS)

Ershkovich, A.I.

1980-01-01

Selected problems of the solar wind - comet tail coupling that are currently accessible to quantitative analysis are reviewed. The model of a comet tail as a plasma cylinder separated by a tangential discontinuity surface from the solar wind is discussed in detail. This model is compatible with the well-known Alfven mechanism of formation of the comet tail. The stability problem of the comet tail boundary (considered as a discontinuity surface) is solved. Under typical conditions a comet tail boundary can undergo the Kelvin-Helmholtz instability. With finite amplitude the stabilizing effect of the magnetic field increases, and waves become stabilized. This model supplies a detailed quantitative description of helical waves observed in type-1 comet tails. A more general model of the tail boundary as a transition layer with a continuous change of the plasma parameters within it is also considered. This theory, in principle, enables us to solve one of the fundamental problems of cometary physics: the magnetic field of the comet tail can be derived from the observations of helical waves. This field turns out to be of the order of the interplanetary field. Various other considerations, discussed in this review also support this conclusion. (orig.)

Influence of Surface Adsorption on Work Function Measurements on Gold-Platinum Interface Using Scanning Kelvin Probe Microscopy

International Nuclear Information System (INIS)

Mugo, Simon; Yuan Jun

2012-01-01

Surface potential difference (SPD) on freshly coated gold and platinum electrodes have been found to be much smaller than bulk work functions consideration and to be dependent on time. We show these discrepancies arise due to formation of surface dipoles caused by adsorbed contaminants in ambient environments. The process is reversible by gentle annealing consistent with contaminant hypothesis. Examination of potential changes on individual electrodes suggest that the Pt surface is more sensitive to ambient conditions than the Au surface in accordance with their relative chemical activities. The result has great implication for interpretation of Kelvin probe measurements obtained on practical devices exposed to ambient environments.

Distinction between magnesium diboride and tetraboride by kelvin probe force microscopy; Unterscheidung von Magnesiumdiborid und Magnesiumtetraborid durch Kelvinsondenkraftmikroskopie

Energy Technology Data Exchange (ETDEWEB)

Kim, Du-Na; Caron, Arnaud; Park, Hai Woong [KoreaTech - Korea Univ. of Technology and Education, Chungnam (Korea, Republic of). School of Energy, Materials and Chemical Engineering

2016-08-15

We analyze mixtures of magnesium diboride and tetraboride synthesized with magnesium powders of different shapes. To distinguish between magnesium diboride and tetraboride we use the contrast of kelvin probe force microscopy. The microstructural morphology strongly depends on the shape of the magnesium powders used in the reaction between magnesium and magnesium tetraboride to form magnesium diboride. With spherical magnesium powder an equiaxed microstructure of magnesium diboride is formed with residual magnesium tetraboride at the grain boundaries. With plate-like magnesium powders elongated magnesium diboride grains are formed. In this case, residual magnesium tetraboride is found to agglomerate.

Magnetohydrodynamic Kelvin-Helmholtz instabilities in astrophysics. 3. Hydrodynamic flows with shear layers

Energy Technology Data Exchange (ETDEWEB)

Ferraro, A [Consiglio Nazionale delle Ricerche, Turin (Italy). Lab. di Cosmo-Geofisica; Max-Planck-Institut fuer Extraterrestrische Physik, Garching (Germany, F.R.)); Massaglia, S [Turin Univ. (Italy). Ist. di Fisica; Trussoni, E [Consiglio Nazionale delle Ricerche, Turin (Italy). Lab. di Cosmo-Geofisica

1982-03-01

In this paper a discussion is presented on Kelvin-Helmholtz instabilities in pressure-confined two-dimensional flows (slabs) delimited by boundary layers with velocity and density gradients. It is found that the fastest growing modes in supersonic flows are produced by perturbations reflecting at the boundaries and have wavelengths of the order of the slab width; this peak of instability is even more evident than in the case of vortex-sheet cylindrical flows, discussed in a previous paper. From a comparison of the results for the two-dimensional slab and three-dimensional cylinder it is concluded that a two-dimensional treatment provides an adequate description of instabilities in fluid flows. In this analogy, symmetric and antisymmetric modes in the slab correspond to pinching and helical modes in the cylinder. In the final section a comparison is attempted of the results obtained with morphologies in collimated jets in extragalactic radio sources; general characteristics appear to be classifiable in terms of scale-lengths of the velocity and density gradients in the boundary layers.

Electronic properties of dioctylterthiophene-based organic thin-film transistors: A Kelvin probe force microscopy study

International Nuclear Information System (INIS)

Afsharimani, N.; Nysten, B.

2013-01-01

It appeared in the past decades that semi-conducting organic liquid crystals could be used as the active layer in organic thin film transistors (OTFTs). They can be processed by simple methods such as inkjet printing, which paves the way to applications for cheap plastic electronics such as electronic tags, biosensors, and flexible screens. However, the measured field-effect mobility in these OTFTs is relatively low compared to inorganic devices. Generally, such low field-effect mobility values result from extrinsic effects such as grain boundaries or imperfect interfaces with source and drain electrodes. It has been shown that reducing the number of grain boundaries between the source and drain electrodes improves the field effect mobility. Therefore, it is important to understand the transport mechanisms by studying the local structure and electronic properties of organic thin films within the channel and at the interfaces with source and drain electrodes in order to improve the field-effect mobility in OTFTs. Kelvin probe force microscopy (KPFM) is an ideal tool for that purpose since it allows to simultaneously investigate the local structure and the electrical potential distribution in electronic devices. In this work, the structure and the electrical properties of OTFTs based on dioctylterthiophene (DOTT) were studied. The transistors were fabricated by spin-coating DOTT on the transistor structures with untreated and treated (silanized) channel silicon oxide. The potential profiles across the channel and at the metal-electrode interfaces were measured by KPFM. The effect of surface treatment on the electrical properties, charge trapping phenomenon and hysteresis effects is demonstrated and analyzed. - Highlights: • Kelvin probe force microscopy study of organic thin film transistors. • Cost and time savings by using solution processable molecules as active layers. • Smaller crystals and less charge trapping effects in silanized devices. • Decrement

Double-reconnected magnetic structures driven by Kelvin-Helmholtz vortices at the Earth's magnetosphere

International Nuclear Information System (INIS)

Borgogno, D.; Califano, F.; Pegoraro, F.; Faganello, M.

2015-01-01

In an almost collisionless magnetohydrodynamic plasma in a relatively strong magnetic field, stresses can be conveyed far from the region where they are exerted, e.g., through the propagation of Alfvèn waves. The forced dynamics of line-tied magnetic structures in solar and stellar coronae (see, e.g., A. F. Rappazzo and E. N. Parker, Astrophys. J. 773, L2 (2013) and references therein) is a paradigmatic case. Here, we investigate how this action at a distance develops from the equatorial region of the Kelvin-Helmholtz unstable flanks of the Earth's magnetosphere leading to the onset, at mid latitude in both hemispheres, of correlated double magnetic field line reconnection events that can allow the solar wind plasma to enter the Earth's magnetosphere

The use of transcutaneous electrical nerve stimulation (tens in the treatment of the spasticity - a review

Directory of Open Access Journals (Sweden)

Dahyan Wagner da Silva Silveira

2008-01-01

Full Text Available This study it has as objective to argue the job of TENS in the spasticity, observing the main parameters, form of application and the mechanism for which TENS it acts in the spasticity. One is about a bibliographical revision based in the literature specialized selected scientific articles through search in the data base of scielo and of bireme, from the sources Medline and Lilacs. The studies found on the job of TENS in the spasticity, had pointed mainly that this chain reduces the spasticity significantly, in lower degrees. The stimulation electrical parameters had disclosed that TENS it (about 100Hz of raised frequency provides one better effect in the reduction of the spasticity. The types of TENS more used had been the conventional and the soon-intense one, however some studies had not presented the used duration of pulse, limit the determination of one better modality of TENS. Few studies had explained the mechanism of performance of the current related one. The ones that had made it, had pointed the release of opioid endogenous (Dynorphins for the central nervous system as main mechanism of performance, however this contrasts with the neurophysiologic bases of the high-frequency stimulation, that demonstrated better resulted in the joined studies. Still it is necessary more studies on the job of this modality of stimulation electrical in the spasticity, since important parameters as duration of pulse, time of application, numbers of attendance and performance mechanism remains without scientific evidence.

Degree-degree correlations in random graphs with heavy-tailed degrees

NARCIS (Netherlands)

Hofstad, van der R.W.; Litvak, N.

2014-01-01

Mixing patterns in large self-organizing networks, such as the Internet, the World Wide Web, social, and biological networks are often characterized by degree-degree dependencies between neighboring nodes. In assortative networks, the degree-degree dependencies are positive (nodes with similar

Degree-Degree Dependencies in Random Graphs with Heavy-Tailed Degrees

NARCIS (Netherlands)

van der Hofstad, Remco; Litvak, Nelly

2014-01-01

Mixing patterns in large self-organizing networks, such as the Internet, the World Wide Web, social, and biological networks are often characterized by degree-degree dependencies between neighboring nodes. In assortative networks, the degree-degree dependencies are positive (nodes with similar

Effect of burst TENS and conventional TENS combined with cryotherapy on pressure pain threshold: randomised, controlled, clinical trial.

Science.gov (United States)

Macedo, L B; Josué, A M; Maia, P H B; Câmara, A E; Brasileiro, J S

2015-06-01

To assess the immediate effect of conventional and burst transcutaneous electrical nerve stimulation (TENS) in combination with cryotherapy on pain threshold and tolerance in healthy individuals. Randomised, controlled trial. University laboratory. One hundred and twelve healthy women. Volunteers were allocated at random to seven groups (n=16): (1) control, (2) placebo TENS, (3) conventional TENS, (4) burst TENS, (5) cryotherapy, (6) cryotherapy in combination with burst TENS, and (7) cryotherapy in combination with conventional TENS. Pain threshold and tolerance were measured by applying a pressure algometer at the lateral epicondyle of the humerus, before and after each intervention. The primary outcome measure was pressure pain threshold. A significant increase in pain threshold and tolerance at the 5% level of significance was recorded as follows: burst TENS {pain threshold: mean difference 1.3 [95% confidence interval (CI) 1.4 to 1.2]; pain tolerance: mean difference 3.8 (95% CI 3.9 to 3.7)}, cryotherapy [pain threshold: mean difference 1.3 (95% CI 1.4 to 1.2); pain tolerance: mean difference 1.9 (95% CI 1.8 to 2.0)] and cryotherapy in combination with burst TENS [pain threshold: mean difference 2.6 (95% CI 2.4 to 2.8); pain tolerance: mean difference 4.9 (95% CI 5.0 to 4.8)]. Cryotherapy in combination with burst TENS provided greater analgesia compared with the other groups (Pcryotherapy in combination with burst TENS to reduce induced pain, and suggest a potentiating effect when these techniques are combined. No such association was found between cryotherapy and conventional TENS. Copyright © 2014 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

A Cloud Greenhouse Effect on Mars: Significant Climate Change in the Recent Past

Science.gov (United States)

Haberle, Robert M.; Kahre, Melinda A.; Schaeffer, James R.; Montmessin, Frank; Phillips, R J.

2012-01-01

The large variations in Mars orbit parameters are known to be significant drivers of climate change on the Red planet. The recent discovery of buried CO2 ice at the South Pole adds another dimension to climate change studies. In this paper we present results from the Ames GCM that show within the past million years it is possible that clouds from a greatly intensified Martian hydrological cycle may have produced a greenhouse effect strong enough to raise global mean surface temperatures by several tens of degrees Kelvin. It is made possible by the ability of the Martian atmosphere to transport water to high altitudes where cold clouds form, reduce the outgoing longwave radiation, and drive up surface temperatures to maintain global energy balance.

TENS (transcutaneous electrical nerve stimulation) for labour pain.

Science.gov (United States)

Francis, Richard

2012-05-01

Because TENS is applied inconsistently and not always in line with optimal TENS application theory, this may explain why TENS for labour pain appears to be effective in some individuals and not in others. This article reviews TENS theory, advises upon optimal TENS application for labour pain and discusses some of the limitations of TENS research on labour pain. TENS application for labour pain may include TENS applied to either side of the lower spine, set to 200 mus pulse duration and 100 pulses per second. As pain increases, TENS intensity should be increased and as pain decreases, TENS intensity should be reduced to maintain a strong but pain free intensity of stimulation. This application may particularly reduce back pain during labour.

Use of 360-degree assessment of residents in internal medicine in a Danish setting

DEFF Research Database (Denmark)

Allerup, Peter

2007-01-01

objectives to be assessed. We considered 22 of these suitable for assessment by 360-degrees assessment. METHODS: Medical departments of six hospitals contributed 42 interns to the study. Each resident was assessed by ten persons of whom one was a secretary, four were nurses and five senior doctors...

Investigation of surface potentials in reduced graphene oxide flake by Kelvin probe force microscopy

Science.gov (United States)

Negishi, Ryota; Takashima, Kai; Kobayashi, Yoshihiro

2018-06-01

The surface potential (SP) of reduced graphene oxide (rGO) flakes prepared by thermal treatments of GO under several conditions was analyzed by Kelvin probe force microscopy. The low-crystalline rGO flakes in which a significant amount of oxygen functional groups and structural defects remain have a much lower SP than mechanically exfoliated graphene free from oxygen and defects. On the other hand, the highly crystalline rGO flake after a thermal treatment for the efficient removal of oxygen functional groups and healing of structural defects except for domain boundary shows SP equivalent to that of the mechanically exfoliated graphene. These results indicate that the work function of rGO is sensitively modulated by oxygen functional groups and structural defects remaining after the thermal reduction process, but is not affected significantly by the domain boundary remaining after the healing of structural defects through the thermal treatment at high temperature.

The evolution of a localized nonlinear wave of the Kelvin-Helmholtz instability with gravity

Science.gov (United States)

Orazzo, Annagrazia; Hoepffner, Jérôme

2012-11-01

At the interface between two fluids of different density and in the presence of gravity, there are well known periodic surface waves which can propagate for long distances with little attenuation, as it is for instance the case at the surface of the sea. If wind is present, these waves progressively accumulate energy as they propagate and grow to large sizes—this is the Kelvin-Helmholtz instability. On the other hand, we show in this paper that for a given wind strength, there is potential for the growth of a localized nonlinear wave. This wave can reach a size such that the hydrostatic pressure drop from top to bottom equals the stagnation pressure of the wind. This process for the disruption of the flat interface is localized and nonlinear. We study the properties of this wave using numerical simulations of the Navier-Stokes equations.

A map of the large day-night temperature gradient of a super-Earth exoplanet.

Science.gov (United States)

Demory, Brice-Olivier; Gillon, Michael; de Wit, Julien; Madhusudhan, Nikku; Bolmont, Emeline; Heng, Kevin; Kataria, Tiffany; Lewis, Nikole; Hu, Renyu; Krick, Jessica; Stamenković, Vlada; Benneke, Björn; Kane, Stephen; Queloz, Didier

2016-04-14

Over the past decade, observations of giant exoplanets (Jupiter-size) have provided key insights into their atmospheres, but the properties of lower-mass exoplanets (sub-Neptune) remain largely unconstrained because of the challenges of observing small planets. Numerous efforts to observe the spectra of super-Earths--exoplanets with masses of one to ten times that of Earth--have so far revealed only featureless spectra. Here we report a longitudinal thermal brightness map of the nearby transiting super-Earth 55 Cancri e (refs 4, 5) revealing highly asymmetric dayside thermal emission and a strong day-night temperature contrast. Dedicated space-based monitoring of the planet in the infrared revealed a modulation of the thermal flux as 55 Cancri e revolves around its star in a tidally locked configuration. These observations reveal a hot spot that is located 41 ± 12 degrees east of the substellar point (the point at which incident light from the star is perpendicular to the surface of the planet). From the orbital phase curve, we also constrain the nightside brightness temperature of the planet to 1,380 ± 400 kelvin and the temperature of the warmest hemisphere (centred on the hot spot) to be about 1,300 kelvin hotter (2,700 ± 270 kelvin) at a wavelength of 4.5 micrometres, which indicates inefficient heat redistribution from the dayside to the nightside. Our observations are consistent with either an optically thick atmosphere with heat recirculation confined to the planetary dayside, or a planet devoid of atmosphere with low-viscosity magma flows at the surface.

Powers of ten

CERN Document Server

1979-01-01

Powers of Ten is a 1977 short documentary film written and directed by Charles Eames and his wife, Ray. The film depicts the relative scale of the Universe in factors of ten (see also logarithmic scale and order of magnitude). The idea for the film appears to have come from the 1957 book Cosmic View by Kees Boeke. The film begins with an aerial image of a man reclining on a blanket; the view is that of one meter across. The viewpoint, accompanied by expository voiceover, then slowly zooms out to a view ten meters across ( or 101 m in standard form), revealing that the man is picnicking in a park with a female companion. The zoom-out continues, to a view of 100 meters (102 m), then 1 kilometer (103 m), and so on, increasing the perspective—the picnic is revealed to be taking place near Soldier Field on Chicago's waterfront—and continuing to zoom out to a field of view of 1024 meters, or the size of the observable universe. The camera then zooms back in to the picnic, and then to views of negative pow...

Opening Doors to Nursing Degrees: Time for Action. A Proposal from Ontario's Colleges

Science.gov (United States)

Colleges Ontario, 2015

2015-01-01

This report argues that Ontario must expand the educational options for people who want to become registered nurses (RNs). It argues that the change Ontario requires is to authorize colleges to offer their own high-quality nursing degrees. Until 2005, about 70 per cent of Ontario's RNs were educated at colleges. Today, tens of thousands of RNs who…

Kelvin probe characterization of buried graphitic microchannels in single-crystal diamond

International Nuclear Information System (INIS)

Bernardi, E.; Battiato, A.; Olivero, P.; Vittone, E.; Picollo, F.

2015-01-01

In this work, we present an investigation by Kelvin Probe Microscopy (KPM) of buried graphitic microchannels fabricated in single-crystal diamond by direct MeV ion microbeam writing. Metal deposition of variable-thickness masks was adopted to implant channels with emerging endpoints and high temperature annealing was performed in order to induce the graphitization of the highly-damaged buried region. When an electrical current was flowing through the biased buried channel, the structure was clearly evidenced by KPM maps of the electrical potential of the surface region overlying the channel at increasing distances from the grounded electrode. The KPM profiling shows regions of opposite contrast located at different distances from the endpoints of the channel. This effect is attributed to the different electrical conduction properties of the surface and of the buried graphitic layer. The model adopted to interpret these KPM maps and profiles proved to be suitable for the electronic characterization of buried conductive channels, providing a non-invasive method to measure the local resistivity with a micrometer resolution. The results demonstrate the potential of the technique as a powerful diagnostic tool to monitor the functionality of all-carbon graphite/diamond devices to be fabricated by MeV ion beam lithography

An Investigation of Hall Currents Associated with Tripolar Magnetic Fields During Magnetospheric Kelvin Helmholtz Waves

Science.gov (United States)

Sturner, A. P.; Eriksson, S.; Newman, D. L.; Lapenta, G.; Gershman, D. J.; Plaschke, F.; Ergun, R.; Wilder, F. D.; Torbert, R. B.; Giles, B. L.; Strangeway, R. J.; Russell, C. T.; Burch, J. L.

2016-12-01

Kinetic simulations and observations of magnetic reconnection suggest the Hall term of Ohm's Law is necessary for understanding fast reconnection in the Earth's magnetosphere. During high (>1) guide field plasma conditions in the solar wind and in Earth's magnetopause, tripolar variations in the guide magnetic field are often observed during current sheet crossings, and have been linked to reconnection Hall magnetic fields. Two proposed mechanisms for these tripolar variations are the presence of multiple nearby X-lines and magnetic island coalescence. We present results of an investigation into the structure of the electron currents supporting tripolar guide magnetic field variations during Kelvin-Helmholtz wave current sheet crossings using the Magnetosphere Multiscale (MMS) Mission, and compare with bipolar magnetic field structures and with kinetic simulations to understand how these tripolar structures may be used as tracers for magnetic islands.

Ten-dimensional anthropomorphic arm control in a human brain-machine interface: difficulties, solutions, and limitations

Science.gov (United States)

Wodlinger, B.; Downey, J. E.; Tyler-Kabara, E. C.; Schwartz, A. B.; Boninger, M. L.; Collinger, J. L.

2015-02-01

Objective. In a previous study we demonstrated continuous translation, orientation and one-dimensional grasping control of a prosthetic limb (seven degrees of freedom) by a human subject with tetraplegia using a brain-machine interface (BMI). The current study, in the same subject, immediately followed the previous work and expanded the scope of the control signal by also extracting hand-shape commands from the two 96-channel intracortical electrode arrays implanted in the subject’s left motor cortex. Approach. Four new control signals, dictating prosthetic hand shape, replaced the one-dimensional grasping in the previous study, allowing the subject to control the prosthetic limb with ten degrees of freedom (three-dimensional (3D) translation, 3D orientation, four-dimensional hand shaping) simultaneously. Main results. Robust neural tuning to hand shaping was found, leading to ten-dimensional (10D) performance well above chance levels in all tests. Neural unit preferred directions were broadly distributed through the 10D space, with the majority of units significantly tuned to all ten dimensions, instead of being restricted to isolated domains (e.g. translation, orientation or hand shape). The addition of hand shaping emphasized object-interaction behavior. A fundamental component of BMIs is the calibration used to associate neural activity to intended movement. We found that the presence of an object during calibration enhanced successful shaping of the prosthetic hand as it closed around the object during grasping. Significance. Our results show that individual motor cortical neurons encode many parameters of movement, that object interaction is an important factor when extracting these signals, and that high-dimensional operation of prosthetic devices can be achieved with simple decoding algorithms. ClinicalTrials.gov Identifier: NCT01364480.

ESTUDO DA INSTABILIDADE KELVIN-HELMHOLTZ ATRAVÉS DE SIMULAÇÕES COM O CÓDIGO ATHENA

Directory of Open Access Journals (Sweden)

Priscila Freitas-Lemes

2013-12-01

Full Text Available As instabilidades Kelvin-Helmholtz são comuns em sistemas astrofísicos e vão desde jatos deburacos negros até disco de acreção protoplantário. Um objeto astrofísico com fortes características da instabilidade de Kelvin-Helmholtz é a Nebulosa de Caraguejo, na qual a expansão do material foi ocasionado pela explosão de uma supernova há, aproximadamente, 1000 anos. Essa instabilidade ocorre no limite entre dois fluidos de diferentes densidades, quando um dos fluidos é acelerado com relação ao outro. Com o objetivo de estudar essa instabilidade, realizamos uma simulação com o código de malha euleriana ATHENA. Para essasimulação, consideramos um domínio quadrado com limites periódicos sobre as laterais, e, refletindo na fronteirada parte superior e inferior. A região superior da caixa é preenchida com um gás de densidade ρ=1,0, pressãoP1=1,0, índice adiabático γ=5/3 e velocidade u1=0,03 na direção x (para direita. A parte inferior tem densidadeρ=2,0, mesma pressão, velocidade e índice adiabático, só que no sentido contrário, para a esquerda. A velocidade é definida como uma função senoidal, que cria a perturbação inicial. Como resultado, observamos o princípio da instabilidade e a formação dos vórtices, com as cristas bem definidas. A nitidez da fronteira entre o material de alta e de baixa densidade está bem conservada, devido à difusão relativamente baixa do algoritmo. Notamos, ainda, que, evoluindo a simulação, os vórtices formados a partir da turbulência fundem-se.

A Review Paper: Contributions from the Gravity and the Kelvin Modes for the Vertical Motion Response.

Directory of Open Access Journals (Sweden)

Julio Buchmann

2009-10-01

Full Text Available In earlier papers of a series of real data integrations of the National Center for Atmospheric Research (NCAR Community Climate Model (CCM with tropical heat anomalies display regions of pronounced subsidence and drying located several thousand kilometers westward poleward of the heating for cases of tropical Atlantic heating and tropical east Pacific heating. This highly predictable sinking response is established within the first five days of these integrations. The normal-modes of a set of nonlinear primitive equations for an atmosphere: Adiabatic, hydrostatic, incompressible, dry, without friction and viscosity are linearized about a basic state at rest and used to partition model response into gravity-inertia and Rossby modes. The emphasis of this review is given upon the contributions of the gravity and Kelvin modes for the vertical motion response.

Ten Lessons from Ten Years PPP Experience in Belgium

NARCIS (Netherlands)

Willems, T.; Verhoest, K.; Voets, J.; Coppens, T.; van Dooren, W.; van den Hurk, M.

2017-01-01

In 2004 Flanders, the northern region of Belgium launched a range of large public–private partnership (PPP) projects for a total value of 6 billion euros. Ten years later, PPP has become a well-embedded procurement method for long-term public infrastructure projects. This article makes a critical

Cluster observations of reconnection due to the Kelvin-Helmholtz instability at the dawnside magnetospheric flank

Directory of Open Access Journals (Sweden)

K. Nykyri

2006-10-01

Full Text Available On 3 July 2001, the four Cluster satellites traversed along the dawnside magnetospheric flank and observed large variations in all plasma parameters. The estimated magnetopause boundary normals were oscillating in the z-direction and the normal component of the magnetic field showed systematic  2–3 min bipolar variations for 1 h when the IMF had a small positive b_z-component and a Parker-spiral orientation in the x,y-plane. Brief  33 s intervals with excellent deHoffman Teller frames were observed satisfying the Walén relation. Detailed comparisons with 2-D MHD simulations indicate that Cluster encountered rotational discontinuities generated by Kelvin-Helmholtz instability. We estimate a wave length of  6 R_E and a wave vector with a significant z-component.

Progress toward Kelvin-Helmholtz instabilities in a High-Energy-Density Plasma on the Nike laser

Science.gov (United States)

Harding, E. C.; Drake, R. P.; Gillespie, R. S.; Grosskopf, M. J.; Huntington, C. M.; Aglitskiy, Y.; Weaver, J. L.; Velikovich, A. L.; Plewa, T.; Dwarkadas, V. V.

2008-04-01

In the realm of high-energy-density (HED) plasmas, there exist three primary hydrodynamic instabilities of concern: Rayleigh-Taylor (RT), Richtmyer-Meshkov (RM), and Kelvin-Helmholtz (KH). Although the RT and the RM instabilities have been readily observed and diagnosed in the laboratory, the KH instability remains relatively unexplored in HED plasmas. Unlike the RT and RM instabilities, the KH instability is driven by a lifting force generated by a strong velocity gradient in a stratified fluid. Understanding the KH instability mechanism in HED plasmas will provide essential insight into oblique shock systems, jets, mass stripping, and detailed RT-spike development. In addition, our KH experiment will help provide the groundwork for future transition to turbulence experiments. We present 2D FLASH simulations and experimental data from our initial attempts to create a pure KH system using the Nike laser at the Naval Research Laboratory.

Vortices in Bose–Einstein condensates: A review of the ...

Indian Academy of Sciences (India)

Rotating dilute Bose–Einstein condensates (BEC) of alkali atoms offer a test- ing ground ... is no many-body theory for strongly interacting Bose particles with which the ex- perimental ... few tens of a micro-Kelvin and trapped in a magnetic trap.

Accurate determination of the Boltzmann constant by Doppler spectroscopy: Towards a new definition of the kelvin

International Nuclear Information System (INIS)

Darquie, B.; Mejri, S.; Sow, P. L. T.; Lemarchand, C.; Triki, M.; Tokunaga, S. K.; Borde, C. J.; Chardonnet, C.; Daussy, C.

2013-01-01

Accurate molecular spectroscopy in the mid-infrared region allows precision measurements of fundamental constants. For instance, measuring the linewidth of an isolated Doppler-broadened absorption line of ammonia around 10 μm enables a determination of the Boltzmann constant k B . We report on our latest measurements. By fitting this lineshape to several models which include Dicke narrowing or speed-dependent collisional effects, we find that a determination of k B with an uncertainty of a few ppm is reachable. This is comparable to the best current uncertainty obtained using acoustic methods and would make a significant contribution to any new value of k B determined by the CODATA. Furthermore, having multiple independent measurements at these accuracies opens the possibility of defining the kelvin by fixing k B , an exciting prospect considering the upcoming redefinition of the International System of Units. (authors)

Multifrequency spectrum analysis using fully digital G Mode-Kelvin probe force microscopy

International Nuclear Information System (INIS)

Collins, Liam; Belianinov, Alex; Somnath, Suhas; Balke, Nina; Kalinin, Sergei V; Jesse, Stephen; Rodriguez, Brian J

2016-01-01

Since its inception over two decades ago, Kelvin probe force microscopy (KPFM) has become the standard technique for characterizing electrostatic, electrochemical and electronic properties at the nanoscale. In this work, we present a purely digital, software-based approach to KPFM utilizing big data acquisition and analysis methods. General mode (G-Mode) KPFM works by capturing the entire photodetector data stream, typically at the sampling rate limit, followed by subsequent de-noising, analysis and compression of the cantilever response. We demonstrate that the G-Mode approach allows simultaneous multi-harmonic detection, combined with on-the-fly transfer function correction—required for quantitative CPD mapping. The KPFM approach outlined in this work significantly simplifies the technique by avoiding cumbersome instrumentation optimization steps (i.e. lock in parameters, feedback gains etc), while also retaining the flexibility to be implemented on any atomic force microscopy platform. We demonstrate the added advantages of G-Mode KPFM by allowing simultaneous mapping of CPD and capacitance gradient (C′) channels as well as increased flexibility in data exploration across frequency, time, space, and noise domains. G-Mode KPFM is particularly suitable for characterizing voltage sensitive materials or for operation in conductive electrolytes, and will be useful for probing electrodynamics in photovoltaics, liquids and ionic conductors. (paper)

Characterization of electronic charged states of P-doped Si quantum dots using AFM/Kelvin probe

International Nuclear Information System (INIS)

Makihara, Katsunori; Xu, Jun; Ikeda, Mitsuhisa; Murakami, Hideki; Higashi, Seiichiro; Miyazaki, Seiichi

2006-01-01

Phosphorous doping to Si quantum dots was performed by a pulse injection of 1% PH 3 diluted with He during the dot formation on thermally grown SiO 2 from thermal decomposition of pure SiH 4 , and electron charging to and discharging from P-doped Si dots were studied to characterize their electronic charged states using a Kelvin probe technique in atomic force microscopy (AFM). The potential change corresponding to the extraction of one electron from each of the P-doped Si dots was observed after applying a tip bias as low as + 0.2 V while for undoped Si dots, with almost the same size as P-doped Si dots, almost the same amount of the potential change was detectable only when the tip bias was increased to ∼ 1 V. It is likely that, for P-doped Si dots, the electron extraction from the conduction band occurs and results in a positively charged state with ionized P donor

Understanding Kelvin-Helmholtz instability in paraffin-based hybrid rocket fuels

Science.gov (United States)

Petrarolo, Anna; Kobald, Mario; Schlechtriem, Stefan

2018-04-01

Liquefying fuels show higher regression rates than the classical polymeric ones. They are able to form, along their burning surface, a low viscosity and surface tension liquid layer, which can become unstable (Kelvin-Helmholtz instability) due to the high velocity gas flow in the fuel port. This causes entrainment of liquid droplets from the fuel surface into the oxidizer gas flow. To better understand the droplets entrainment mechanism, optical investigations on the combustion behaviour of paraffin-based hybrid rocket fuels in combination with gaseous oxygen have been conducted in the framework of this research. Combustion tests were performed in a 2D single-slab burner at atmospheric conditions. High speed videos were recorded and analysed with two decomposition techniques. Proper orthogonal decomposition (POD) and independent component analysis (ICA) were applied to the scalar field of the flame luminosity. The most excited frequencies and wavelengths of the wave-like structures characterizing the liquid melt layer were computed. The fuel slab viscosity and the oxidizer mass flow were varied to study their influence on the liquid layer instability process. The combustion is dominated by periodic, wave-like structures for all the analysed fuels. Frequencies and wavelengths characterizing the liquid melt layer depend on the fuel viscosity and oxidizer mass flow. Moreover, for very low mass flows, no wavelength peaks are detected for the higher viscosity fuels. This is important to better understand and predict the onset and development of the entrainment process, which is connected to the amplification of the longitudinal waves.

Ten major trends now emerging in the United States

Energy Technology Data Exchange (ETDEWEB)

Naisbitt, J.

1978-01-01

Using a special analytical procedure for tracking and assessing events reported in the nation's newspapers, the Center for Policy Process has identified ten emerging trends in the United States that are having a major impact on all our lives and on all businesses and industries--and especially on the electric utility industry. Although the trends may move in contradictory directions and have different degrees of significance, all have been carefully monitored for a considerable length of time. All are firmly established--and are not to be viewed as the momentary interests of certain radical elements of the population. The ten trends are: the fast-emerging clash between nuclear fuel and coal as an environmental health issue; displacement of racism and sexism by ''ageism'' as society's most prominent anti-discrimination preoccupation, and the complete elimination soon of mandatory retirement; in government and technology, the phenomenon of ''appropriate scale'' replacing economies of scale, emergence of single-issue political organizations; coming-of-age of the recycling ethic; emergence of ''access to capital'' as the new equity issue--the new rights issue; continuing shift from centralization to decentralization; movement of society in the dual directions of high technology/high touch; business' increasing involvement with the well-established accountability trend; and shift from a representative democracy to a participatory democracy--this profound change in American democracy actually began about a decade or so ago.

Polarity analysis of GaN nanorods by photo-assisted Kelvin probe force microscopy

Energy Technology Data Exchange (ETDEWEB)

Wei, Jiandong; Neumann, Richard; Wang, Xue; Li, Shunfeng; Fuendling, Soenke; Merzsch, Stephan; Al-Suleiman, Mohamed A.M.; Soekmen, Uensal; Wehmann, Hergo-H.; Waag, Andreas [Institut fuer Halbleitertechnik, TU Braunschweig (Germany)

2011-07-15

Polarity dependence (N-polar (000-1) and Ga-polar (0001)) of surface photovoltage of epitaxially grown, vertically aligned GaN nanorods has been investigated by photo-assisted Kelvin probe force microscopy (KPFM). Commercial GaN substrates with known polarities are taken as reference samples. The polarity of GaN substrates can be well distinguished by the change in surface photovoltage upon UV illumination in air ambient. These different behaviors of Ga- and N-polar surfaces are attributed to the polarity-related surface-bound charges and photochemical reactivity. GaN nanorods were grown on patterned SiO{sub 2}/sapphire templates by metal-organic vapor phase epitaxy (MOVPE). In order to analyze the bottom surface of the grown GaN nanorods, a technique known from high power electronics and joining techniques is applied to remove the substrate. The top and bottom surfaces of the GaN nanorods are identified to be N-polar and Ga-polar according to the KPFM results, respectively. Our experiments demonstrate that KPFM is a simple and suitable method capable to identify the polarity of GaN nanorods. (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Spatial distribution of rolled up Kelvin-Helmholtz vortices at Earth's dayside and flank magnetopause

Directory of Open Access Journals (Sweden)

M. G. G. T. Taylor

2012-06-01

Full Text Available The Kelvin-Helmholtz Instability (KHI can drive waves at the magnetopause. These waves can grow to form rolled-up vortices and facilitate transfer of plasma into the magnetosphere. To investigate the persistence and frequency of such waves at the magnetopause we have carried out a survey of all Double Star 1 magnetopause crossings, using a combination of ion and magnetic field measurements. Using criteria originally used in a Geotail study made by Hasegawa et al. (2006 (forthwith referred to as H2006, 17 candidate events were identified from the entire TC-1 mission (covering ~623 orbits where the magnetopause was sampled, a majority of which were on the dayside of the terminator. The relationship between density and shear velocity was then investigated, to identify the predicted signature of a rolled up vortex from H2006 and all 17 events exhibited some level of rolled up behavior. The location of the events had a clear dawn-dusk asymmetry, with 12 (71% on the post noon, dusk flank suggesting preferential growth in this region.

The Supersymmetric Top-Ten Lists

OpenAIRE

Haber, Howard E.

1993-01-01

Ten reasons are given why supersymmetry is the leading candidate for physics beyond the Standard Model. Ultimately, the experimental discovery of supersymmetric particles at future colliders will determine whether supersymmetry is relevant for TeV scale physics. The grand hope of supersymmetry enthusiasts is to connect TeV scale supersymmetry with Planck scale physics. The ten most pressing theoretical problems standing in the way of this goal are briefly described.

Understanding S-shaped current-voltage characteristics of organic solar cells: Direct measurement of potential distributions by scanning Kelvin probe

Science.gov (United States)

Saive, Rebecca; Mueller, Christian; Schinke, Janusz; Lovrincic, Robert; Kowalsky, Wolfgang

2013-12-01

We present a comparison of the potential distribution along the cross section of bilayer poly(3-hexylthiophene)/1-(3-methoxycarbonyl)propyl-1-phenyl[6,6]C61 (P3HT/PCBM) solar cells, which show normal and anomalous, S-shaped current-voltage (IV) characteristics. We expose the cross sections of the devices with a focussed ion beam and measure them with scanning Kelvin probe microscopy. We find that in the case of S-shaped IV-characteristics, there is a huge potential drop at the PCBM/Al top contact, which does not occur in solar cells with normal IV-characteristics. This behavior confirms the assumption that S-shaped curves are caused by hindered charge transport at interfaces.

Understanding S-shaped current-voltage characteristics of organic solar cells: Direct measurement of potential distributions by scanning Kelvin probe

International Nuclear Information System (INIS)

Saive, Rebecca; Kowalsky, Wolfgang; Mueller, Christian; Schinke, Janusz; Lovrincic, Robert

2013-01-01

We present a comparison of the potential distribution along the cross section of bilayer poly(3-hexylthiophene)/1-(3-methoxycarbonyl)propyl-1-phenyl[6,6]C61 (P3HT/PCBM) solar cells, which show normal and anomalous, S-shaped current-voltage (IV) characteristics. We expose the cross sections of the devices with a focussed ion beam and measure them with scanning Kelvin probe microscopy. We find that in the case of S-shaped IV-characteristics, there is a huge potential drop at the PCBM/Al top contact, which does not occur in solar cells with normal IV-characteristics. This behavior confirms the assumption that S-shaped curves are caused by hindered charge transport at interfaces

ALGORITHMS FOR TETRAHEDRAL NETWORK (TEN) GENERATION

Institute of Scientific and Technical Information of China (English)

无

2000-01-01

The Tetrahedral Network(TEN) is a powerful 3-D vector structure in GIS, which has a lot of advantages such as simple structure, fast topological relation processing and rapid visualization. The difficulty of TEN application is automatic creating data structure. Al though a raster algorithm has been introduced by some authors, the problems in accuracy, memory requirement, speed and integrity are still existent. In this paper, the raster algorithm is completed and a vector algorithm is presented after a 3-D data model and structure of TEN have been introducted. Finally, experiment, conclusion and future work are discussed.

A new relativistic viscous hydrodynamics code and its application to the Kelvin-Helmholtz instability in high-energy heavy-ion collisions

Energy Technology Data Exchange (ETDEWEB)

Okamoto, Kazuhisa [Nagoya University, Department of Physics, Nagoya (Japan); Nonaka, Chiho [Nagoya University, Department of Physics, Nagoya (Japan); Nagoya University, Kobayashi-Maskawa Institute for the Origin of Particles and the Universe (KMI), Nagoya (Japan); Duke University, Department of Physics, Durham, NC (United States)

2017-06-15

We construct a new relativistic viscous hydrodynamics code optimized in the Milne coordinates. We split the conservation equations into an ideal part and a viscous part, using the Strang spitting method. In the code a Riemann solver based on the two-shock approximation is utilized for the ideal part and the Piecewise Exact Solution (PES) method is applied for the viscous part. We check the validity of our numerical calculations by comparing analytical solutions, the viscous Bjorken's flow and the Israel-Stewart theory in Gubser flow regime. Using the code, we discuss possible development of the Kelvin-Helmholtz instability in high-energy heavy-ion collisions. (orig.)

A new relativistic viscous hydrodynamics code and its application to the Kelvin-Helmholtz instability in high-energy heavy-ion collisions

Science.gov (United States)

Okamoto, Kazuhisa; Nonaka, Chiho

2017-06-01

We construct a new relativistic viscous hydrodynamics code optimized in the Milne coordinates. We split the conservation equations into an ideal part and a viscous part, using the Strang spitting method. In the code a Riemann solver based on the two-shock approximation is utilized for the ideal part and the Piecewise Exact Solution (PES) method is applied for the viscous part. We check the validity of our numerical calculations by comparing analytical solutions, the viscous Bjorken's flow and the Israel-Stewart theory in Gubser flow regime. Using the code, we discuss possible development of the Kelvin-Helmholtz instability in high-energy heavy-ion collisions.

The five times ten things everyone should have had in their hands before they are ten and two years old.

Science.gov (United States)

Hut, R.; Poot, A.

2017-12-01

To train the young ones to become people that make stuff, I present the five times ten things we use a lot that everyone should have used before they are ten and two years old. I will bring at least two times ten of these things and show them live to you! And: I will bring a large paper for you to bring home with those five times ten things on it to put in the hands of your kids!

Local work function analysis of Pt/TiO2 photocatalyst by a Kelvin probe force microscope

International Nuclear Information System (INIS)

Hiehata, K; Sasahara, A; Onishi, H

2007-01-01

Nanometre-sized Pt clusters were prepared on a TiO 2 (110)-(1 x 1) surface, and the lateral distribution of work function was examined by using a Kelvin probe force microscope. Local work function on the Pt clusters was smaller than that on the surrounding TiO 2 surface. Assuming that the dipole moments which perturb the work function are produced by uneven electron distribution, the decrease of the work function indicates electron transfer from the clusters to the TiO 2 surface. After decomposition of pivalate anions on the surfaces by UV irradiation, the work function increased on some Pt clusters. It is known that holes photoexcited in TiO 2 attach to pivalate anions to cause a decomposition reaction. Hence the increase of the observed work function by UV irradiation can be ascribed to the trapping of the accompanying electrons to the Pt clusters

Champagne for the cryogenics teams

CERN Multimedia

2005-01-01

Christmas has come early for the LHC as a complete sector of the cryogenic distribution line has been operating at 10 degrees Kelvin (-263°C) for the past two weeks, just a few degrees above the machine's nominal operating temperature.

Tens bij bevallingen

NARCIS (Netherlands)

Tuin-Nuis, F.D.F.

2000-01-01

TENS (Transcutane Electrische Neuro Stimulatie) is een pijnverlichtingsmethode die berust op de Gate Control Theory van Melzack en Wall. Door middel van electrische pulsen via de huid zou de geleiding van nociceptieve signalen (pijnprikkels) worden beïnvloed en zou het lichaam endorfinen aanmaken:

Ten steps to a cooler planet

International Nuclear Information System (INIS)

2001-01-01

The overwhelming scientific consensus is that human activities, especially activities that produce greenhouse gases are accumulating in the atmosphere and are changing the intricate balance that has sustained life on earth for millions of years. The estimate is that in Canada about 35 per cent of the greenhouse gases released to the atmosphere come from personal sources. This booklet provides brief account of the ways that individuals contribute to green house gas emissions and provides some helpful hints on how to reduce this personal contribution to the climate change problem. The ten ways suggested are: (1) use public transport as much as possible, (2) buy smaller cars , (3) use the train instead of flying, make fewer long distance trips by combining business and vacation travel, (4) set the thermostat one degree lower and save 525 kg of carbon dioxide per year, (5) avoid overhousing by choosing a smaller house and by making every square foot count, (6) buy energy efficient appliances, (7) reduce water heater's energy consumption by insulating it, (8) reduce meat intake and buy locally produced food in season, (9) minimize garbage production by reusing and recycling, (10) use green power wherever available and contribute to the development of renewable energy sources

Increasing intensity of TENS prevents analgesic tolerance in rats

Science.gov (United States)

Sato, Karina L.; Sanada, Luciana S.; Rakel, Barbara A.; Sluka, Kathleen A.

2012-01-01

Transcutaneous electrical nerve stimulation (TENS) reduces hyperalgesia and pain. Both low frequency (LF) and high frequency (HF) TENS, delivered at the same intensity (90% motor threshold (MT)) daily, result in analgesic tolerance with repeated use by the 5th day of treatment. Thecurrentstudytestedif 1) increasingintensityby 10% per daypreventsthedevelopmentoftolerance to repeated TENS, and 2) iflowerintensity TENS (50 % MT) produces an equivalentreduction in hyperalgesia when compared to 90% MT TENS. Sprague-Dawley rats with unilateral knee joint inflammation (3% carrageenan) were separated according to the intensity of TENS used: Sham, 50% LF, 50% HF, 90% LF, 90% HF, and increased intensity by 10% per day (LF and HF). The reduced mechanical withdrawal threshold following the induction of inflammation was reversed by application of TENS applied at 90% MT and increasing intensity for the first 4 days. On the 5th day, the groups that received 90% MT intensity showed tolerance. Nevertheless, the group that received an increased intensity on each day still showed a reversal of the mechanical withdrawal threshold with TENS. These results show that the development of tolerance can be delayed by increasing intensity of TENS. PMID:22858165

Potential profile and photovoltaic effect in nanoscale lateral pn junction observed by Kelvin probe force microscopy

International Nuclear Information System (INIS)

Nowak, Roland; Moraru, Daniel; Mizuno, Takeshi; Jablonski, Ryszard; Tabe, Michiharu

2014-01-01

Nanoscale pn junctions have been investigated by Kelvin probe force microscopy and several particular features were found. Within the depletion region, a localized noise area is observed, induced by temporal fluctuations of dopant states. Electronic potential landscape is significantly affected by dopants with ground-state energies deeper than in bulk. Finally, the effects of light illumination were studied and it was found that the depletion region shifts its position as a function of light intensity. This is ascribed to charge redistribution within the pn junction as a result of photovoltaic effect and due to the impact of deepened-level dopants. - Highlights: • In pn nano-junctions, temporal potential fluctuations are found in depletion layer. • Fluctuations are due to frequent capture and emission of free carriers by dopants. • Depletion layer position shifts as a function of the intensity of irradiated light. • The depletion layer shifts are due to changes of deep-level dopants' charge states

Degree-degree correlations in directed networks with heavy-tailed degrees

NARCIS (Netherlands)

van der Hoorn, W.L.F.; Litvak, Nelli

2013-01-01

In network theory, Pearson's correlation coefficients are most commonly used to measure the degree assortativity of a network. We investigate the behavior of these coefficients in the setting of directed networks with heavy-tailed degree sequences. We prove that for graphs where the in- and

Degree-degree dependencies in directed networks with heavy-tailed degrees

NARCIS (Netherlands)

van der Hoorn, W.L.F.; Litvak, Nelly

2015-01-01

In network theory, Pearson’s correlation coefficients are most commonly used to measure the degree assortativity of a network. We investigate the behavior of these coefficients in the setting of directed networks with heavy-tailed degree sequences. We prove that for graphs where the in- and

Observations and computations of narrow Kelvin ship wakes

Directory of Open Access Journals (Sweden)

Francis Noblesse

2016-01-01

Full Text Available Computations of far-field ship waves, based on linear potential flow theory and the Hogner approximation, are reported for monohull ships and catamarans. Specifically, far-field ship waves are computed for six monohull ships at four Froude numbers F≡V/gL=0.58, 0.68, 0.86, 1.58 and for six catamarans with nondimensional hull spacing s≡S/L=0.25 at two Froude numbers Fs≡V/gS=1 and 2.5. Here, g is the gravitational acceleration, V and L denote the ship speed and length, and S is the separation distance between the twin hulls of a catamaran. The computations show that, although the amplitudes of the waves created by a ship are strongly influenced by the shape of the ship hull, as well known, the ray angles where the largest waves are found are only weakly influenced by the hull shape and indeed are mostly a kinematic feature of the flow around a ship hull. An important practical consequence of this flow feature is that the apparent wake angle of general monohull ships or catamarans (with arbitrarily-shaped hulls can be estimated, without computations, by means of simple analytical relations; these relations, obtained elsewhere via parametric computations, are given here. Moreover, the influence of the two parameters Fs and s that largely determine the ray angles of the dominant waves created by a catamaran is illustrated via computations for three catamarans with hull spacings s=0.2, 0.35, 0.5 at four Froude numbers Fs=1, 1.5, 2, 2.5. These computations confirm that the largest waves created by wide and/or fast catamarans are found at ray angles that only depend on Fs (i.e. that do not depend on the hull spacing s in agreement with an elementary analysis of lateral interference between the dominant waves created by the bows (or sterns of the twin hulls of a catamaran. The dominant-waves ray angles predicted by the theory of wave-interference effects for monohull ships and catamarans are also compared with the observations of narrow Kelvin ship

Self-assembled monolayers of alkyl-thiols on InAs: A Kelvin probe force microscopy study

Science.gov (United States)

Szwajca, A.; Wei, J.; Schukfeh, M. I.; Tornow, M.

2015-03-01

We report on the preparation and characterization of self-assembled monolayers from aliphatic thiols with different chain length and termination on InAs (100) planar surfaces. This included as first step the development and investigation of a thorough chemical InAs surface preparation step using a dedicated bromine/NH4OH-based etching process. Ellipsometry, contact angle measurements and atomic force microscopy (AFM) indicated the formation of smooth, surface conforming monolayers. The molecular tilt angles were obtained as 30 ± 10° with respect to the surface normal. Kelvin probe force microscopy (KPFM) measurements in hand with Parameterized Model number 5 (PM5) calculations of the involved molecular dipoles allowed for an estimation of the molecular packing densities on the surface. We obtained values of up to n = 1014 cm- 2 for the SAMs under study. These are close to what is predicted from a simple geometrical model that would calculate a maximum density of about n = 2.7 × 1014 cm- 2. We take this as additional conformation of the substrate smoothness and quality of our InAs-SAM hybrid layer systems.

Transcutaneous electrical nerve stimulation (TENS) for pain relief in labour.

Science.gov (United States)

Dowswell, Therese; Bedwell, Carol; Lavender, Tina; Neilson, James P

2009-04-15

Transcutaneous nerve stimulation (TENS) has been proposed as a means of reducing pain in labour. The TENS unit emits low-voltage electrical impulses which vary in frequency and intensity. During labour, TENS electrodes are generally placed on the lower back, although TENS may be used to stimulate acupuncture points or other parts of the body. The physiological mechanisms whereby TENS relieves pain are uncertain. The TENS unit is frequently operated by women, which may increase sense of control in labour. To assess the effects of TENS on pain in labour. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (November 2008). Randomised controlled trials comparing women receiving TENS for pain relief in labour versus routine care, alternative pharmacological methods of pain relief, or placebo devices. We included all types of TENS machines. Two review authors assessed for inclusion all trials identified by the search strategy, carried out data extraction and assessed risk of bias. We have recorded reasons for excluding studies. The search identified 25 studies; we excluded six and included 19 studies including 1671 women. Fifteen examined TENS applied to the back, two to acupuncture points and two to the cranium. Overall, there was little difference in pain ratings between TENS and control groups, although women receiving TENS to acupuncture points were less likely to report severe pain (risk ratio 0.41, 95% confidence interval 0.32 to 0.55). The majority of women using TENS said they would be willing to use it again in a future labour. Where TENS was used as an adjunct to epidural analgesia there was no evidence that it reduced pain. There was no consistent evidence that TENS had any impact on interventions and outcomes in labour. There was little information on outcomes for mothers and babies. No adverse events were reported. There is only limited evidence that TENS reduces pain in labour and it does not seem to have any impact (either positive or

Determination of Schottky barrier heights and Fermi-level unpinning at the graphene/n-type Si interfaces by X-ray photoelectron spectroscopy and Kelvin probe

International Nuclear Information System (INIS)

Lin, Yow-Jon; Zeng, Jian-Jhou

2014-01-01

Highlights: • The interface characteristics of graphene/n-type Si devices are measured. • The actual work function of graphene is examined with the Kelvin probe. • An analysis is conducted according to the Schottky–Mott limit. • The Fermi energy level at the graphene/n-type Si interfaces is unpinned. • The Schottky barrier value is dependent on the work function of graphene. - Abstract: The interface characteristics of graphene/n-type Si samples using X-ray photoelectron spectroscopy (XPS) measurements are investigated. XPS makes it possible to extract a reliable Schottky barrier value. For graphene/n-type Si samples with (without) sulfide treatment, the Schottky barrier height is 0.86 (0.78) eV. The Schottky barrier height was increased from 0.78 to 0.86 eV, indicating that sulfide treatment is effective in passivating the surface of Si (owing to the formation of Si–S bonds). To determine the Fermi-level pinning/unpinning at the graphene/n-type Si interfaces with sulfide treatment, an analysis is conducted according to the Schottky–Mott limit and the actual work function of graphene is examined with the Kelvin probe. It is shown that the Fermi energy level is unpinned and the Schottky barrier value is dependent on the work function of graphene. Investigation of graphene/n-type Si interfaces is important, and providing the other technique for surface potential control is possible

Numerical studies of the Kelvin-Hemholtz instability in a coronal jet

Science.gov (United States)

Zhao, Tian-Le; Ni, Lei; Lin, Jun; Ziegler, Udo

2018-04-01

Kelvin-Hemholtz (K-H) instability in a coronal EUV jet is studied via 2.5D MHD numerical simulations. The jet results from magnetic reconnection due to the interaction of the newly emerging magnetic field and the pre-existing magnetic field in the corona. Our results show that the Alfvén Mach number along the jet is about 5–14 just before the instability occurs, and it is even higher than 14 at some local areas. During the K-H instability process, several vortex-like plasma blobs with high temperature and high density appear along the jet, and magnetic fields have also been rolled up and the magnetic configuration including anti-parallel magnetic fields forms, which leads to magnetic reconnection at many X-points and current sheet fragments inside the vortex-like blob. After magnetic islands appear inside the main current sheet, the total kinetic energy of the reconnection outflows decreases, and cannot support the formation of the vortex-like blob along the jet any longer, then the K-H instability eventually disappears. We also present the results about how the guide field and flux emerging speed affect the K-H instability. We find that a strong guide field inhibits shock formation in the reconnecting upward outflow regions but helps secondary magnetic islands appear earlier in the main current sheet, and then apparently suppresses the K-H instability. As the speed of the emerging magnetic field decreases, the K-H instability appears later, the highest temperature inside the vortex blob gets lower and the vortex structure gets smaller.

Ultrasound combined transcutaneous electrical nerve stimulation (UltraTENS) versus phonophoresis of piroxicam (PhP) in symptomatic knee osteoarthritis: A randomized double-blind, controlled trial.

Science.gov (United States)

Boonhong, Jariya; Suntornpiyapan, Phitsanu; Piriyajarukul, Apatchanee

2018-02-02

Ultrasound combined with transcutaneous electrical nerve stimulation (UltraTENS) and phonophoresis of piroxicam (PhP) are combined modality therapy that frequently used in musculoskeletal pain including knee osteoarthritis (OA). But it is lack of a good clinical trial to prove and compare their effects. To compare the effects of UltraTENS with PhP on mild to moderate degree of symptomatic knee OA. Sixty-one patients (55 women), mean age of 63.4 ± 8.1 y, 50-90 mm VAS of knee pain and Kellgren-Lawrence score of grade I-III were randomly allocated into UltraTENS and PhP (N = 31 and 30, respectively). The UltraTENS group received a combined ultrasound with TENS program and a non-drug gel, whereas the PhP group got an ultrasound program with piroxicam gel and sham TENS. All patients were treated for a total of 10 sessions, consisting of five times per week and 10 min per session. Before and after treatment, patients were evaluated knee pain by using the 100-mm VAS and functional performance by Western Ontario and McMaster Universities Osteoarthritis (WOMAC) index. The UltraTENS and PhP groups experienced considerable improvement in both VAS and total WOMAC scores post-treatment (PPhP had better VAS of pain and WOMAC scores but no statistical significance. Results show that UltraTENS and PhP were effective for relieving pain and improve functionality knee OA without significant differences between their effects.

Development of a model to determine mass transfer coefficient and oxygen solubility in bioreactors

Directory of Open Access Journals (Sweden)

Johnny Lee

2017-02-01

where T is in degree Kelvin, and the subscripts refer to degree Celsius; E, ρ, σ are properties of water. Furthermore, using data from published data on oxygen solubility in water, it was found that solubility bears a linear and inverse relationship with the mass transfer coefficient.

Transcutaneous electrical nerve stimulation (TENS) for pain management in labour

Science.gov (United States)

Dowswell, Therese; Bedwell, Carol; Lavender, Tina; Neilson, James P

2014-01-01

Background Transcutaneous nerve stimulation (TENS) has been proposed as a means of reducing pain in labour. The TENS unit emits low-voltage electrical impulses which vary in frequency and intensity. During labour, TENS electrodes are generally placed on the lower back, although TENS may be used to stimulate acupuncture points or other parts of the body. The physiological mechanisms whereby TENS relieves pain are uncertain. TENS machines are frequently operated by women, which may increase a sense of control in labour. Objectives To assess the effects of TENS on pain in labour. Search methods We searched the Cochrane Pregnancy and Childbirth Group’s Trials Register (30 April 2011) and reference lists of retrieved papers. Selection criteria Randomised controlled trials comparing women receiving TENS for pain management in labour versus routine care, alternative non-pharmacological methods of pain relief, or placebo devices. We included all types of TENS machines. Data collection and analysis Two review authors assessed for inclusion all trials identified by the search strategy, carried out data extraction and assessed risk of bias. We have recorded reasons for excluding studies. Main results Seventeen trials with 1466 women contribute data to the review. Thirteen examined TENS applied to the back, two to acupuncture points, and two to the cranium. Overall, there was little difference in pain ratings between TENS and control groups, although women receiving TENS to acupuncture points were less likely to report severe pain (average risk ratio 0.41, 95% confidence interval 0.31 to 0.54; measured in two studies). The majority of women using TENS said they would be willing to use it again in a future labour. Where TENS was used as an adjunct to epidural analgesia there was no evidence that it reduced pain. There was no consistent evidence that TENS had any impact on interventions and outcomes in labour. There was little information on outcomes for mothers and babies. No

Kelvin probe force microscopy in liquid using electrochemical force microscopy

Directory of Open Access Journals (Sweden)

Liam Collins

2015-01-01

Full Text Available Conventional closed loop-Kelvin probe force microscopy (KPFM has emerged as a powerful technique for probing electric and transport phenomena at the solid–gas interface. The extension of KPFM capabilities to probe electrostatic and electrochemical phenomena at the solid–liquid interface is of interest for a broad range of applications from energy storage to biological systems. However, the operation of KPFM implicitly relies on the presence of a linear lossless dielectric in the probe–sample gap, a condition which is violated for ionically-active liquids (e.g., when diffuse charge dynamics are present. Here, electrostatic and electrochemical measurements are demonstrated in ionically-active (polar isopropanol, milli-Q water and aqueous NaCl and ionically-inactive (non-polar decane liquids by electrochemical force microscopy (EcFM, a multidimensional (i.e., bias- and time-resolved spectroscopy method. In the absence of mobile charges (ambient and non-polar liquids, KPFM and EcFM are both feasible, yielding comparable contact potential difference (CPD values. In ionically-active liquids, KPFM is not possible and EcFM can be used to measure the dynamic CPD and a rich spectrum of information pertaining to charge screening, ion diffusion, and electrochemical processes (e.g., Faradaic reactions. EcFM measurements conducted in isopropanol and milli-Q water over Au and highly ordered pyrolytic graphite electrodes demonstrate both sample- and solvent-dependent features. Finally, the feasibility of using EcFM as a local force-based mapping technique of material-dependent electrostatic and electrochemical response is investigated. The resultant high dimensional dataset is visualized using a purely statistical approach that does not require a priori physical models, allowing for qualitative mapping of electrostatic and electrochemical material properties at the solid–liquid interface.

Transcutaneous electrical nerve stimulation (TENS) for neuropathic pain in adults.

Science.gov (United States)

Gibson, William; Wand, Benedict M; O'Connell, Neil E

2017-09-14

Neuropathic pain, which is due to nerve disease or damage, represents a significant burden on people and society. It can be particularly unpleasant and achieving adequate symptom control can be difficult. Non-pharmacological methods of treatment are often employed by people with neuropathic pain and may include transcutaneous electrical nerve stimulation (TENS). This review supersedes one Cochrane Review 'Transcutaneous electrical nerve stimulation (TENS) for chronic pain' (Nnoaham 2014) and one withdrawn protocol 'Transcutaneous electrical nerve stimulation (TENS) for neuropathic pain in adults' (Claydon 2014). This review replaces the original protocol for neuropathic pain that was withdrawn. To determine the analgesic effectiveness of TENS versus placebo (sham) TENS, TENS versus usual care, TENS versus no treatment and TENS in addition to usual care versus usual care alone in the management of neuropathic pain in adults. We searched CENTRAL, MEDLINE, Embase, PsycINFO, AMED, CINAHL, Web of Science, PEDro, LILACS (up to September 2016) and various clinical trials registries. We also searched bibliographies of included studies for further relevant studies. We included randomised controlled trials where TENS was evaluated in the treatment of central or peripheral neuropathic pain. We included studies if they investigated the following: TENS versus placebo (sham) TENS, TENS versus usual care, TENS versus no treatment and TENS in addition to usual care versus usual care alone in the management of neuropathic pain in adults. Two review authors independently screened all database search results and identified papers requiring full-text assessment. Subsequently, two review authors independently applied inclusion/exclusion criteria to these studies. The same review authors then independently extracted data, assessed for risk of bias using the Cochrane standard tool and rated the quality of evidence using GRADE. We included 15 studies with 724 participants. We found a

Application of scanning Kelvin probe microscopy for the electrical characterization of microcrystalline silicon for photovoltaics

International Nuclear Information System (INIS)

Breymesser, A.

2000-05-01

In the last years microcrystalline silicon thin films have attracted great attention as a new photovoltaic material. With this material it is possible to combine simple and cheap low temperature deposition techniques known from amorphous silicon with the long-term stability of the photovoltaic performance like in bulk crystalline silicon solar cells. The critical point is the deposition procedure with numerous tunable parameters influencing the quality and character of the produced diode structures. Additionally there is a great uncertainty about unintentionally incorporated defects, which is not affected by the deposition parameters. Extended investigation of the material, diode and solar cell characteristics is essential in order to correlate the impact of deposition conditions with the quality of the devices. The situation is complicated due to the anisotropic and inhomogeneous character of microcrystalline silicon. Scanning Kelvin probe microscopy (SKPM) is a work function measurement method based on a scanning force microscope (SFM) and a modified Kelvin probe technique. Due to the excellent lateral resolution of the SFM work function measurements with resolutions far below the micrometer level can be carried out. Applied on doped microcrystalline silicon structures it is possible to visualize the position of the Fermi level within the band gap and the influence of the deposition conditions on it. Within this work a SKPM based on a commercially available SFM was constructed and built. Great effort was concentrated on the characterization of the SKPM experiment. On the basis of an extended knowledge about the performance investigations concentrated on cross sections of microcrystalline silicon diode structures produced by hot-wire chemical vapor deposition (HW-CVD). A pin structure for the diodes was chosen due to the low diffusion lengths within this rather defective material. The evolution of the built-in electric drift field within the intrinsic absorber is

The TEN-T core network and the Fehmarnbelt region

DEFF Research Database (Denmark)

Guasco, Clement Nicolas

This note is a snapshot picture, taken in early 2014, that places the Green STRING corridor project within the context of the TEN-T strategy and gives a summarized overview on the impact of this strategy in the region. Chapter 1 contains a summary of the TEN-T strategy today, chapter 2 presents...... the sources used for this note, chapter 3 presents all the relevant EU regulations with direct impact on the development of TEN-T corridors, chapter 4 gives practical examples of the challenges for the development of TEN-T corridors, chapter 5 pre-sents the national initiatives related to the TEN-T corridor...

Entangling a nanomechanical resonator and a superconducting microwave cavity

International Nuclear Information System (INIS)

Vitali, D.; Tombesi, P.; Woolley, M. J.; Doherty, A. C.; Milburn, G. J.

2007-01-01

We propose a scheme able to entangle at the steady state a nanomechanical resonator with a microwave cavity mode of a driven superconducting coplanar waveguide. The nanomechanical resonator is capacitively coupled with the central conductor of the waveguide and stationary entanglement is achievable up to temperatures of tens of milliKelvin

Global reconnection topology as inferred from plasma observations inside Kelvin-Helmholtz vortices

Directory of Open Access Journals (Sweden)

M. B. Bavassano Cattaneo

2010-04-01

Full Text Available During a long lasting period of northward interplanetary magnetic field and high solar wind speed (above 700 km/s, the Cluster spacecraft go across a number of very large rolled-up Kelvin-Helmholtz (KH vortices at the dusk magnetopause, close to the terminator. The peculiarity of the present event is a particular sequence of ions and electrons distribution functions observed repeatedly inside each vortex. In particular, whenever Cluster crosses the current layer inside the vortices, multiple field-aligned ion populations appear, suggesting the occurrence of reconnection. In addition, the ion data display a clear velocity filter effect both at the leading and at the trailing edge of each vortex. This effect is not present in the simultaneous electron data. Unlike other KH studies reported in the literature in which reconnection occurs within the vortices, in the present event the observations are not compatible with local reconnection, but are accounted for by lobe reconnection occurring along an extended X-line at the terminator in the Southern Hemisphere. The reconnected field lines "sink" across the magnetopause and then convect tailward-duskward where they become embedded in the vortices. Another observational evidence is the detected presence of solar wind plasma on the magnetospheric side of the vortices, which confirms unambiguously the occurrence of mass transport across the magnetopause already reported in the literature. The proposed reconnection scenario accounts for all the observational aspects, regarding both the transport process and the kinetic signatures.

Transcutaneous electric nerve stimulation (TENS) in dentistry- A review.

Science.gov (United States)

Kasat, Vikrant; Gupta, Aditi; Ladda, Ruchi; Kathariya, Mitesh; Saluja, Harish; Farooqui, Anjum-Ara

2014-12-01

Transcutaneous electric nerve stimulation (TENS) is a non-pharmacological method which is widely used by medical and paramedical professionals for the management of acute and chronic pain in a variety of conditions. Similarly, it can be utilized for the management of pain during various dental procedures as well as pain due to various conditions affecting maxillofacial region. This review aims to provide an insight into clinical research evidence available for the analgesic and non analgesic uses of TENS in pediatric as well as adult patients related to the field of dentistry. Also, an attempt is made to briefly discuss history of therapeutic electricity, mechanism of action of TENS, components of TENs equipment, types, techniques of administration, advantages and contradictions of TENS. With this we hope to raise awareness among dental fraternity regarding its dental applications thereby increasing its use in dentistry. Key words:Dentistry, pain, TENS.

The Fourier-Kelvin Stellar Interferometer (FKSI) Nulling Testbed II: Closed-loop Path Length Metrology And Control Subsystem

Science.gov (United States)

Frey, B. J.; Barry, R. K.; Danchi, W. C.; Hyde, T. T.; Lee, K. Y.; Martino, A. J.; Zuray, M. S.

2006-01-01

The Fourier-Kelvin Stellar Interferometer (FKSI) is a mission concept for an imaging and nulling interferometer in the near to mid-infrared spectral region (3-8 microns), and will be a scientific and technological pathfinder for upcoming missions including TPF-I/DARWIN, SPECS, and SPIRIT. At NASA's Goddard Space Flight Center, we have constructed a symmetric Mach-Zehnder nulling testbed to demonstrate techniques and algorithms that can be used to establish and maintain the 10(exp 4) null depth that will be required for such a mission. Among the challenges inherent in such a system is the ability to acquire and track the null fringe to the desired depth for timescales on the order of hours in a laboratory environment. In addition, it is desirable to achieve this stability without using conventional dithering techniques. We describe recent testbed metrology and control system developments necessary to achieve these goals and present our preliminary results.

Contact resistance asymmetry of amorphous indium-gallium-zinc-oxide thin-film transistors by scanning Kelvin probe microscopy

Science.gov (United States)

Chen-Fei, Wu; Yun-Feng, Chen; Hai, Lu; Xiao-Ming, Huang; Fang-Fang, Ren; Dun-Jun, Chen; Rong, Zhang; You-Dou, Zheng

2016-05-01

In this work, a method based on scanning Kelvin probe microscopy is proposed to separately extract source/drain (S/D) series resistance in operating amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistors. The asymmetry behavior of S/D contact resistance is deduced and the underlying physics is discussed. The present results suggest that the asymmetry of S/D contact resistance is caused by the difference in bias conditions of the Schottky-like junction at the contact interface induced by the parasitic reaction between contact metal and a-IGZO. The overall contact resistance should be determined by both the bulk channel resistance of the contact region and the interface properties of the metal-semiconductor junction. Project supported by the Key Industrial R&D Program of Jiangsu Province, China (Grant No. BE2015155), the Priority Academic Program Development of Higher Education Institutions of Jiangsu Province, China, and the Fundamental Research Funds for the Central Universities, China (Grant No. 021014380033).

Direct observation of crosssectional potential distribution in GaN-based MIS structures by Kelvin-probe force microscopy

Energy Technology Data Exchange (ETDEWEB)

Kaneko, Masamitsu; Kikawa, Junjiroh [Research Organization of Science and Engineering, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu, Shiga 525-8577 (Japan); Fujishima, Tatsuya; Chikamatsu, Kentaro; Yamaguchi, Atsushi; Otake, Hirotaka [Research and Development Headquarters, ROHM Co., Ltd., 21 Saiin Mizosaki-Cho, Ukyo-ku, Kyoto 615-8585 (Japan); Nanishi, Yasushi [Department of Photonics, Ritsumeikan University, 1-1-1 Noji-Higashi, Kusatsu, Shiga 525-8577 (Japan)

2009-06-15

Cross-sectional potential distribution in GaN-based trench gate metal-insulator-semiconductor field-effect transistors (MISFET) at off- and operating-state has been investigated by using Kelvin-probe force microscopy to clarify the actual operating situation of trench gate MISFET. The potential distribution reflecting the wafer structure, n/p/n{sup -}/n{sup +}, is observed as shown in the right figure. At the off-state (the gate voltage is fixed to 0 V), it is found that the electric field at the internal p/n{sup -} interface become strong, on the contrary to that at top n/p interface is almost unchanged by the stepwise increase of the drain bias from 0 to 15 V. From the analysis of results obtained at operating state, we can confirm the situation how the channel forms by increasing the gate voltage. This information is useful for designing devices and improving their characteristics (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Ten steps to successful software process improvement

Science.gov (United States)

Kandt, R. K.

2003-01-01

This paper identifies ten steps for managing change that address organizational and cultural issues. Four of these steps are critical, that if not done, will almost guarantee failure. This ten-step program emphasizes the alignment of business goals, change process goals, and the work performed by the employees of an organization.

Quantitative dopant profiling in semiconductors. A new approach to Kelvin probe force microscopy

Energy Technology Data Exchange (ETDEWEB)

Baumgart, Christine

2012-07-01

Failure analysis and optimization of semiconducting devices request knowledge of their electrical properties. To meet the demands of today's semiconductor industry, an electrical nanometrology technique is required which provides quantitative information about the doping profile and which enables scans with a lateral resolution in the sub-10 nm range. In the presented work it is shown that Kelvin probe force microscopy (KPFM) is a very promising electrical nanometrology technique to face this challenge. The technical and physical aspects of KPFM measurements on semiconductors required for the correct interpretation of the detected KPFM bias are discussed. A new KPFM model is developed which enables the quantitative correlation between the probed KPFM bias and the dopant concentration in the investigated semiconducting sample. Quantitative dopant profiling by means of the new KPFM model is demonstrated by the example of differently structured, n- and p-type doped silicon. Additionally, the transport of charge carriers during KPFM measurements, in particular in the presence of intrinsic electric fields due to vertical and horizontal pn junctions as well as due to surface space charge regions, is discussed. Detailed investigations show that transport of charge carriers in the semiconducting sample is a crucial aspect and has to be taken into account when aiming for a quantitative evaluation of the probed KPFM bias.

Rocket Observations of Kelvin Waves in the Upper Stratosphere over India.

Science.gov (United States)

Devarajan, M.; Reddy, C. A.; Ragrava Reddi, C.

1985-09-01

The upper atmospheric winds (20-40 km) at two Indian stations, Sriharikota Range (SHAR 13.7°N, 80.2°E) and Balasore (2 1.5°N, 86.93°E) during the years 1979-80 were analyzed for short scale vertical variations (6-16 km) of the zonal wind. The analysis involves high-pass filtering of the wind profiles to extract the short-scale wavelike perturbations and Fourier analysis of the wave disturbances.The results of the analysis are presented. The dominant vertical wavelengths are in the 6-12 km range in 67% of the observed cases, and the amplitudes are significantly larger during the easterly background wind. The amplitudes are systematically larger by about a factor of 2 at Sriharikota (13.7°N) than at 1Wasore (21.5°N). Corresponding wave perturbations are absent in the meridional wind in as much as 70% of the observations. These characteristics lead to the conclusion that the observed wavelike disturbances are the manifestation of Kelvin waves in the upper stratosphere. In some cases, the periods of the waves are inferred to be in the range of 4-8 days. The short vertical wavelengths, together with the shorter periods, indicate the possible dominance of zonal wavenumber 2 during many disturbance events.The observations of the wave activity in relation to the semiannual oscillation (SAO) and the annual oscillation (AO) show that 1) the more active periods correspond to the easterly phase of the SAO in the middle stratosphere and that 2) the wave activity persists for a longer duration when both the AO and SAO are in easterly phase.

Nanoscale Surface Photovoltage Mapping of 2D Materials and Heterostructures by Illuminated Kelvin Probe Force Microscopy

KAUST Repository

Shearer, Melinda J.

2018-02-01

Nanomaterials are interesting for a variety of applications, such as optoelectronics and photovoltaics. However, they often have spatial heterogeneity, i.e. composition change or physical change in the topography or structure, which can lead to varying properties that would influence their applications. New techniques must be developed to understand and correlate spatial heterogeneity with changes in electronic properties. Here we highlight the technique of surface photovoltage-Kelvin probe force microscopy (SPV-KFM), which is a modified version of non-contact atomic force microscopy capable of imaging not only the topography and surface potential, but also the surface photovoltage on the nanoscale. We demonstrate its utility in probing monolayer WSe2-MoS2 lateral heterostructures, which form an ultrathin p-n junction promising for photovoltaic and optoelectronic applications. We show surface photovoltage maps highlighting the different photoresponse of the two material regions as a result of the effective charge separation across this junction. Additionally, we study the variations between different heterostructure flakes and emphasize the importance of controlling the synthesis and transfer of these materials to obtain consistent properties and measurements.

Direct assessment of p-n junctions in single GaN nanowires by Kelvin probe force microscopy

Science.gov (United States)

Minj, Albert; Cros, Ana; Auzelle, Thomas; Pernot, Julien; Daudin, Bruno

2016-09-01

Making use of Kelvin probe force microscopy, in dark and under ultraviolet illumination, we study the characteristics of p-n junctions formed along the axis of self-organized GaN nanowires (NWs). We map the contact potential difference of the single NW p-n junctions to locate the space charge region and directly measure the depletion width and the junction voltage. Simulations indicate a shrinkage of the built-in potential for NWs with small diameter due to surface band bending, in qualitative agreement with the measurements. The photovoltage of the NW/substrate contact is studied by analyzing the response of NW segments with p- and n-type doping under illumination. Our results show that the shifts of the Fermi levels, and not the changes in surface band bending, are the most important effects under above band-gap illumination. The quantitative electrical information obtained here is important for the use of NW p-n junctions as photovoltaic or rectifying devices at the nanoscale, and is especially relevant since the technique does not require the formation of ohmic contacts to the NW junction.

Nanoscale Surface Photovoltage Mapping of 2D Materials and Heterostructures by Illuminated Kelvin Probe Force Microscopy

KAUST Repository

Shearer, Melinda J.; Li, Ming-yang; Li, Lain-Jong; Jin, Song; Hamers, Robert J

2018-01-01

Nanomaterials are interesting for a variety of applications, such as optoelectronics and photovoltaics. However, they often have spatial heterogeneity, i.e. composition change or physical change in the topography or structure, which can lead to varying properties that would influence their applications. New techniques must be developed to understand and correlate spatial heterogeneity with changes in electronic properties. Here we highlight the technique of surface photovoltage-Kelvin probe force microscopy (SPV-KFM), which is a modified version of non-contact atomic force microscopy capable of imaging not only the topography and surface potential, but also the surface photovoltage on the nanoscale. We demonstrate its utility in probing monolayer WSe2-MoS2 lateral heterostructures, which form an ultrathin p-n junction promising for photovoltaic and optoelectronic applications. We show surface photovoltage maps highlighting the different photoresponse of the two material regions as a result of the effective charge separation across this junction. Additionally, we study the variations between different heterostructure flakes and emphasize the importance of controlling the synthesis and transfer of these materials to obtain consistent properties and measurements.

Magnetic field control of 90 Degree-Sign , 180 Degree-Sign , and 360 Degree-Sign domain wall resistance

Energy Technology Data Exchange (ETDEWEB)

Majidi, Roya, E-mail: royamajidi@gmail.com [Department of Physics, Shahid Rajaee Teacher Training University, Lavizan, 16788-15811 Tehran (Iran, Islamic Republic of)

2012-10-01

In the present work, we have compared the resistance of the 90 Degree-Sign , 180 Degree-Sign , and 360 Degree-Sign domain walls in the presence of external magnetic field. The calculations are based on the Boltzmann transport equation within the relaxation time approximation. One-dimensional Neel-type domain walls between two domains whose magnetization differs by angle of 90 Degree-Sign , 180 Degree-Sign , and 360 Degree-Sign are considered. The results indicate that the resistance of the 360 Degree-Sign DW is more considerable than that of the 90 Degree-Sign and 180 Degree-Sign DWs. It is also found that the domain wall resistance can be controlled by applying transverse magnetic field. Increasing the strength of the external magnetic field enhances the domain wall resistance. In providing spintronic devices based on magnetic nanomaterials, considering and controlling the effect of domain wall on resistivity are essential.

ac driving amplitude dependent systematic error in scanning Kelvin probe microscope measurements: Detection and correction

International Nuclear Information System (INIS)

Wu Yan; Shannon, Mark A.

2006-01-01

The dependence of the contact potential difference (CPD) reading on the ac driving amplitude in scanning Kelvin probe microscope (SKPM) hinders researchers from quantifying true material properties. We show theoretically and demonstrate experimentally that an ac driving amplitude dependence in the SKPM measurement can come from a systematic error, and it is common for all tip sample systems as long as there is a nonzero tracking error in the feedback control loop of the instrument. We further propose a methodology to detect and to correct the ac driving amplitude dependent systematic error in SKPM measurements. The true contact potential difference can be found by applying a linear regression to the measured CPD versus one over ac driving amplitude data. Two scenarios are studied: (a) when the surface being scanned by SKPM is not semiconducting and there is an ac driving amplitude dependent systematic error; (b) when a semiconductor surface is probed and asymmetric band bending occurs when the systematic error is present. Experiments are conducted using a commercial SKPM and CPD measurement results of two systems: platinum-iridium/gap/gold and platinum-iridium/gap/thermal oxide/silicon are discussed

Symbiotic stars according to IRAS observations

International Nuclear Information System (INIS)

Luud, L.; Tuvikene, T.

1987-01-01

Symbiotic stars contained in Allen's catalog are examined with a view to establishing their coincidence with sources of far infrared radiation in the catalog of point sources observed with the IRAS satellite. Altogether, 72 symbiotic or suspected symbiotic objects have been identified. A list of the identified stars has been compiled, and the energy distributions in the infrared spectra of selected stars are given. It has been found that the presence of dust in symbiotic systems is a more widespread phenomenon than hitherto believed. Almost 40% of them are dust systems. Among them, objects with dust temperature of several tens of degrees kelvin have been found. It is shown that the only useful two-color diagram is the (K - m 12 )-(m 12 - m 25 ) diagram. Finally, attention is drawn to a type of symbiotic stars having cold components of the spectral class G; these require a special investigation

The origin of the future ten questions for the next ten years

CERN Document Server

Gribbin, John

2006-01-01

How did the universe begin? Where do galaxies come from? How do stars and planets form? Where do the material particles we are made of come from? How did life begin? Today we have only provisional answers to such questions. But scientific progress will improve these answers dramatically over the next ten years, predicts John Gribbin in this riveting book. He focuses on what we know—or think we know—about ten controversial, unanswered issues in the physical sciences and explains how current cutting-edge research may yield solutions in the very near future. With his trademark facility for engaging readers with or without a scientific background, the author explores ideas concerning the creation of the universe, the possibility of other forms of life, and the fate of the expanding cosmos. He examines “theories of everything,” including grand unified theories and string theory, and he discusses the Big Bang theory, the origin of structure and patterns of matter in the galaxies, and dark mass and dark ene...

Electrical conductivity measurement on DKDP Crystals with different deuterated degrees

International Nuclear Information System (INIS)

Liu, Baoan; Yin, Xin; Xu, Mingxia; Ji, Shaohua; Zhu, Lili; Zhang, Lisong; Sun, Xun; Xu, Xinguang; Zhao, Minglei; Zhang, Qinghua

2012-01-01

Ten DKDP single crystals with deuterated degrees ranging from 0 to 90 % were grown by a rapid growth method. The electrical conductivities of these crystals were measured along a and c directions at room temperature. The electrical conductivity increases with the increase for deuterium content. Also, the electrical conductivities of certain crystals were measured at various temperatures ranging from 20 to 130 C. The values of activation energy decrease as the increase of deuterium content. The present study indicates that the deuterium tunneling frequency is smaller than that of hydrogen, which may be the reason why the variation of electrical conductivity happens after the substitution of hydrogen for deuterium in KDP crystal. (orig.)

Transcutaneous electrical nerve stimulation (TENS) for chronic low back pain.

Science.gov (United States)

Milne, S; Welch, V; Brosseau, L; Saginur, M; Shea, B; Tugwell, P; Wells, G

2001-01-01

Low back pain (LBP) affects a large proportion of the population. Transcutaneous electrical nerve stimulation (TENS) was introduced more than 30 years ago as an alternative therapy to pharmacological treatments for chronic pain. However, despite its widespread use, the effectiveness of TENS is still controversial. The aim of this systematic review was to determine the efficacy of TENS in the treatment of chronic LBP. We searched MEDLINE, EMBASE, PEDro and the Cochrane Controlled Trials Register up to June 1, 2000. Only randomized controlled clinical trials of TENS for the treatment of patients with a clinical diagnosis of chronic LBP were included. Abstracts were excluded unless further data could be obtained from the authors. Two reviewers independently selected trials and extracted data using predetermined forms. Heterogeneity was tested with Cochran's Q test. A fixed effects model was used throughout for continuous variables, except where heterogeneity existed, in which case, a random effects model was used. Results are presented as weighted mean differences (WMD) with 95% confidence intervals (95% CI), where the difference between the treated and control groups was weighted by the inverse of the variance. Standardized mean differences (SMD) were calculated by dividing the difference between the treated and control by the baseline variance. SMD were used when different scales were used to measure the same concept. Dichotomous outcomes were analyzed with odds ratios. Five trials were included, with 170 subjects randomized to the placebo group receiving sham-TENS and 251 subjects receiving active TENS (153 for conventional mode, 98 for acupuncture-like TENS). The schedule of treatments varied greatly between studies ranging from one treatment/day for two consecutive days, to three treatments/day for four weeks. There were no statistically significant differences between the active TENS group when compared to the placebo TENS group for any outcome measures

Global Simulations of the Asymmetry in Forming Kelvin-Helmholtz Instability at Mercury

Science.gov (United States)

Paral, J.; Rankin, R.

2013-12-01

MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) is the first spacecraft to provide data from the orbit of Mercury. After the probe's insertion into the orbit on March 2011, the in situ measurements revealed a dawn-dusk asymmetry in the observations of Kelvin-Helmholtz (KH) instability. This instability forms at the magnetopause boundary due to the high shear of the plasma flows. The asymmetry in the observations is unexpected and largely unexplained, although it has been speculated that finite ion gyroradius effect plays an important role. The large gyroradius implies that kinetic effects are important and thus must be taken into account. We employ global ion hybrid-kinetic simulations to obtain a 2D model of Mercury's magnetosphere. This code treats ions as particles and follows the full trajectory while electrons act as a charge neutralizing fluid. The planet is treated as the perfect conductor placed in the streaming solar wind to form a quasi steady state of the magnetosphere. By placing a virtual probe in the simulation domain we obtain time series of the plasma parameters which can be compared to the observations by the MESSENGER spacecraft. The comparison of the KH instability is remarkably close to the observations of MESSENGER; to within a factor of two. The model also confirms the asymmetry in the observations. The ion density obtained from the computer model is shown together with velocity vectors (represented by arrows). The solid line represents the trajectory of the third flyby of MESSENGER on September 29, 2009.

Electrical Potential of Acupuncture Points: Use of a Noncontact Scanning Kelvin Probe

Directory of Open Access Journals (Sweden)

Brian J. Gow

2012-01-01

Full Text Available Objective. Acupuncture points are reportedly distinguishable by their electrical properties. However, confounders arising from skin-to-electrode contact used in traditional electrodermal methods have contributed to controversies over this claim. The Scanning Kelvin Probe is a state-of-the-art device that measures electrical potential without actually touching the skin and is thus capable of overcoming these confounding effects. In this study, we evaluated the electrical potential profiles of acupoints LI-4 and PC-6 and their adjacent controls. We hypothesize that acupuncture point sites are associated with increased variability in potential compared to adjacent control sites. Methods. Twelve healthy individuals were recruited for this study. Acupuncture points LI-4 and PC-6 and their adjacent controls were assessed. A 2 mm probe tip was placed over the predetermined skin site and adjusted to a tip-to-sample distance of 1.0 mm under tip oscillation settings of 62.4 Hz frequency. A surface potential scan spanning a 1.0 cm × 1.0 cm area was obtained. Results. At both the PC-6 and LI-4 sites, no significant differences in mean potential were observed compared to their respective controls (Wilcoxon rank-sum test, and 0.79, resp.. However, the LI-4 site was associated with significant increase in variability compared to its control as denoted by standard deviation and range ( and 0.0005, resp.. At the PC-6 site, no statistical differences in variability were observed. Conclusion. Acupuncture points may be associated with increased variability in electrical potential.

The system Cu-Rh-S at 900 degrees, 700 degrees, 540 degrees and 500 degrees C

DEFF Research Database (Denmark)

Karup-Møller, Sven; Makovicky, E.

2007-01-01

Phase relations in the dry condensed system Cu-Rh-S were determined at 900, 700, 540 and 500 degrees C. At 900 degrees C, the system contains digenite, four rhodium sulfides (Rh17S15, Rh3S4, Rh2S3 and RhS similar to 3), three ternary sulfides (CuRh2S4, CuxRhS3+x and a fibrous sulfide in the range...

A Ten-Year Reflection

Science.gov (United States)

Phillip, Cyndi

2016-01-01

Five initiatives launched during Cyndi Phillip's term as American Association of School Librarians (AASL) President (2006-2007) continue to have an impact on school librarians ten years later. They include the rewriting of AASL's learning standards, introduction of the SKILLS Act, the presentation of the Crystal Apple Award to Scholastic Library…

When Graduate Degrees Prostitute the Educational Process: Degrees Gone Wild

Science.gov (United States)

Lumadue, Richard T.

2006-01-01

Graduate degrees prostitute the educational process when they are sold to consumers by unaccredited degree/diploma mills as being equivalent to legitimate, bona-fide degrees awarded by accredited graduate schools. This article carefully analyzes the serious problems of bogus degrees and their association with the religious higher education…

Supersymmetric gauged scale covariance in ten and lower dimensions

International Nuclear Information System (INIS)

Nishino, Hitoshi; Rajpoot, Subhash

2004-01-01

We present globally supersymmetric models of gauged scale covariance in ten, six, and four dimensions. This is an application of a recent similar gauging in three dimensions for a massive self-dual vector multiplet. In ten dimensions, we couple a single vector multiplet to another vector multiplet, where the latter gauges the scale covariance of the former. Due to scale covariance, the system does not have a Lagrangian formulation, but has only a set of field equations, like Type IIB supergravity in ten dimensions. As by-products, we construct similar models in six dimensions with N=(2,0) supersymmetry, and four dimensions with N=1 supersymmetry. We finally get a similar model with N=4 supersymmetry in four dimensions with consistent interactions that have never been known before. We expect a series of descendant theories in dimensions lower than ten by dimensional reductions. This result also indicates that similar mechanisms will work for other vector and scalar multiplets in space-time lower than ten dimensions

Effect of dopant density on contact potential difference across n-type GaAs homojunctions using Kelvin Probe Force Microscopy

Science.gov (United States)

Boumenou, C. Kameni; Urgessa, Z. N.; Djiokap, S. R. Tankio; Botha, J. R.; Nel, J.

2018-04-01

In this study, cross-sectional surface potential imaging of n+/semi-insulating GaAs junctions is investigated by using amplitude mode kelvin probe force microscopy. The measurements have shown two different potential profiles, related to the difference in surface potential between the semi-insulating (SI) substrate and the epilayers. It is shown that the contact potential difference (CPD) between the tip and the sample is higher on the semi-insulating substrate side than on the n-type epilayer side. This change in CPD across the interface has been explained by means of energy band diagrams indicating the relative Fermi level positions. In addition, it has also been found that the CPD values across the interface are much smaller than the calculated values (on average about 25% of the theoretical values) and increase with the electron density. Therefore, the results presented in study are only in qualitative agreement with the theory.

Affordances: Ten Years On

Science.gov (United States)

Brown, Jill P.; Stillman, Gloria

2014-01-01

Ten years ago the construct, affordance, was rising in prominence in scholarly literature. A proliferation of different uses and meanings was evident. Beginning with its origin in the work of Gibson, we traced its development and use in various scholarly fields. This paper revisits our original question with respect to its utility in mathematics…

Hypoalgesia in response to transcutaneous electrical nerve stimulation (TENS) depends on stimulation intensity.

Science.gov (United States)

Moran, Fidelma; Leonard, Tracey; Hawthorne, Stephanie; Hughes, Ciara M; McCrum-Gardner, Evie; Johnson, Mark I; Rakel, Barbara A; Sluka, Kathleen A; Walsh, Deirdre M

2011-08-01

Transcutaneous electrical nerve stimulation (TENS) is an electrophysical modality used for pain management. This study investigated the dose response of different TENS intensities on experimentally induced pressure pain. One hundred and thirty TENS naïve healthy individuals (18-64 years old; 65 males, 65 females) were randomly allocated to 5 groups (n = 26 per group): Strong Non Painful TENS; Sensory Threshold TENS; Below Sensory Threshold TENS; No Current Placebo TENS; and Transient Placebo TENS. Active TENS (80 Hz) was applied to the forearm for 30 minutes. Transient Placebo TENS was applied for 42 seconds after which the current amplitude automatically reset to 0 mA. Pressure pain thresholds (PPT) were recorded from 2 points on the hand and forearm before and after TENS to measure hypoalgesia. There were significant differences between groups at both the hand and forearm (ANOVA; P = .005 and .002). At 30 minutes, there was a significant hypoalgesic effect in the Strong Non Painful TENS group compared to: Below Sensory Threshold TENS, No Current Placebo TENS and Transient Placebo TENS groups (P TENS and No Current Placebo TENS groups at the hand (P = .001). There was no significant difference between Strong Non Painful TENS and Sensory Threshold TENS groups. The area under the curve for the changes in PPT significantly correlated with the current amplitude (r(2) = .33, P = .003). These data therefore show that there is a dose-response effect of TENS with the largest effect occurring with the highest current amplitudes. This study shows a dose response for the intensity of TENS for pain relief with the strongest intensities showing the greatest effect; thus, we suggest that TENS intensity should be titrated to achieve the strongest possible intensity to achieve maximum pain relief. Copyright © 2011 American Pain Society. Published by Elsevier Inc. All rights reserved.

Investigation of the surface potential of TiO2 (110) by frequency-modulation Kelvin probe force microscopy

Science.gov (United States)

Kou, Lili; Li, Yan Jun; Kamijyo, Takeshi; Naitoh, Yoshitaka; Sugawara, Yasuhiro

2016-12-01

We investigate the surface potential distribution on a TiO2 (110)-1 × 1 surface by Kelvin probe force microscopy (KPFM) and atom-dependent bias-distance spectroscopic mapping. The experimental results demonstrate that the local contact potential difference increases on twofold-coordinated oxygen sites, and decreases on OH defects and fivefold-coordinated Ti sites. We propose a qualitative model to explain the origin of the surface potential of TiO2 (110). We qualitatively calculate the surface potential induced by chemical potential and permanent surface dipole. The calculated results agree with our experimental ones. Therefore, we suggest that the surface potential of TiO2 (110) is dominated not only by the permanent surface dipole between the tip apex atom and surface, but also by the dipoles induced by the chemical interaction between the tip and sample. The KPFM technique demonstrate the possibility of investigation of the charge transfer phenomenon on TiO2 surface under gas conditions. It is useful for the elucidation of the mechanism of the catalytic reactions.

Ten Things Every Professor Should Know about Assessment

Science.gov (United States)

Wolf, Kenneth; Dunlap, Joanna; Stevens, Ellen

2012-01-01

This article describes ten key assessment practices for advancing student learning that all professors should be familiar with and strategically incorporate in their classrooms and programs. Each practice or concept is explained with examples and guidance for putting it into practice. The ten are: learning outcomes, performance assessments,…

Second-degree discrete Painleve equations conceal first-degree ones

International Nuclear Information System (INIS)

Ramani, A; Grammaticos, B; Joshi, N

2010-01-01

We examine various second-degree difference equations which have been proposed over the years and according to their authors' claims should be integrable. This study is motivated by the fact that we consider that second-degree discrete systems cannot be integrable due to the proliferation of the images (and pre-images) of the initial point. We show that in the present cases no contradiction exists. In all cases examined, we show that there exists an underlying integrable first-degree mapping which allows us to obtain an appropriate solution of the second-degree one.

Low-Temperature Reduction of Graphene Oxide: Electrical Conductance and Scanning Kelvin Probe Force Microscopy

Science.gov (United States)

Slobodian, Oleksandr M.; Lytvyn, Peter M.; Nikolenko, Andrii S.; Naseka, Victor M.; Khyzhun, Oleg Yu.; Vasin, Andrey V.; Sevostianov, Stanislav V.; Nazarov, Alexei N.

2018-05-01

Graphene oxide (GO) films were formed by drop-casting method and were studied by FTIR spectroscopy, micro-Raman spectroscopy (mRS), X-ray photoelectron spectroscopy (XPS), four-points probe method, atomic force microscopy (AFM), and scanning Kelvin probe force (SKPFM) microscopy after low-temperature annealing at ambient conditions. It was shown that in temperature range from 50 to 250 °C the electrical resistivity of the GO films decreases by seven orders of magnitude and is governed by two processes with activation energies of 6.22 and 1.65 eV, respectively. It was shown that the first process is mainly associated with water and OH groups desorption reducing the thickness of the film by 35% and causing the resistivity decrease by five orders of magnitude. The corresponding activation energy is the effective value determined by desorption and electrical connection of GO flakes from different layers. The second process is mainly associated with desorption of oxygen epoxy and alkoxy groups connected with carbon located in the basal plane of GO. AFM and SKPFM methods showed that during the second process, first, the surface of GO plane is destroyed forming nanostructured surface with low work function and then at higher temperature a flat carbon plane is formed that results in an increase of the work function of reduced GO.

Hybrid simulations of plasma transport by Kelvin-Helmholtz instability at the magnetopause: magnetic shear

Energy Technology Data Exchange (ETDEWEB)

Cowee, Misa M [Los Alamos National Laboratory; Winske, Dan [Los Alamos National Laboratory; Gary, S Peter [Los Alamos National Laboratory

2009-01-01

Two-dimensional hybrid (kinetic ions, massless fluid electrons) simulations of the Kelvin Helmholtz Instability (KHI) for a magnetopause configuration with a magnetic shear across the boundary are carried out to examine how the transport of magnetosheath plasma into the magnetosphere is affected by the shear field. Low magnetic shear conditions where the magnetosheath magnetic field is within 30{sup o} of northward is included in the simulations because KHI is thought to be important for plasma transport only for northward or near-northward interplanetary magnetic field orientations. The simulations show that coherent vortices can grow for these near-northward angles, and that they are sometimes more coherent than for pure northward conditions because the turbulence which breaks-down these vortices is reduced when there are magnetic tension forces. With increasing magnetic shear angle, the growth rate is reduced, and the vortices do not grow to as large of size which reduces the plasma transport. By tracking the individual particle motions diffusion coefficients can be obtained for the system, where the diffusion is not classical in nature but instead has a time dependence resulting from both the increasingly large-scale vortex motion and the small-scale turbulence generated in the break-down of the instabilities. Results indicate that diffusion on the order of 10{sup 9} m{sup 2}/s could possibly be generated by KHI on the flanks of the magnetosphere.

TRANSCUTANEOUS ELECTRICAL NERVE-STIMULATION (TENS) IN RAYNAUDS-PHENOMENON

NARCIS (Netherlands)

MULDER, P; DOMPELING, EC; VANSLOCHTERENVANDERBOOR, JC; KUIPERS, WD; SMIT, AJ

Transcutaneous nerve stimulation (TENS) has been described as resulting in vasodilatation. The effect of 2 Hz TENS of the right hand during forty-five minutes on skin temperature and plethysmography of the third digit of both hands and feet and on transcutaneous oxygen tension (TcpO2) of the right

The Kelvin-Helmholtz instability in National Ignition Facility hohlraums as a source of gold-gas mixing

Energy Technology Data Exchange (ETDEWEB)

Vandenboomgaerde, M.; Bonnefille, M.; Gauthier, P. [CEA, DAM, DIF, F-91297 Arpajon (France)

2016-05-15

Highly resolved radiation-hydrodynamics FCI2 simulations have been performed to model laser experiments on the National Ignition Facility. In these experiments, cylindrical gas-filled hohlraums with gold walls are driven by a 20 ns laser pulse. For the first time, simulations show the appearance of Kelvin-Helmholtz (KH) vortices at the interface between the expanding wall material and the gas fill. In this paper, we determine the mechanisms which generate this instability: the increase of the gas pressure around the expanding gold plasma leads to the aggregation of an over-dense gold layer simultaneously with shear flows. At the surface of this layer, all the conditions are met for a KH instability to grow. Later on, as the interface decelerates, the Rayleigh-Taylor instability also comes into play. A potential scenario for the generation of a mixing zone at the gold-gas interface due to the KH instability is presented. Our estimates of the Reynolds number and the plasma diffusion width at the interface support the possibility of such a mix. The key role of the first nanosecond of the laser pulse in the instability occurrence is also underlined.

Experimental determination of conduction and valence bands of semiconductor nanoparticles using Kelvin probe force microscopy

International Nuclear Information System (INIS)

Zhang Wen; Chen Yongsheng

2013-01-01

The ability to determine a semiconductor’s band edge positions is important for the design of new photocatalyst materials. In this paper, we introduced an experimental method based on Kelvin probe force microscopy to determine the conduction and valence band edge energies of semiconductor nanomaterials, which has rarely been demonstrated. We tested the method on six semiconductor nanoparticles (α-Fe 2 O 3 , CeO 2 , Al 2 O 3 , CuO, TiO 2 , and ZnO) with known electronic structures. The experimentally determined band edge positions for α-Fe 2 O 3 , Al 2 O 3 , and CuO well matched the literature values with no statistical difference. Except CeO 2 , all other metal oxides had a consistent upward bias in the experimental measurements of band edge positions because of the shielding effect of the adsorbed surface water layer. This experimental approach may outstand as a unique alternative way of probing the band edge energy positions of semiconductor materials to complement the current computational methods, which often find limitations in new synthetic or complex materials. Ultimately, this work provides scientific foundation for developing experimental tools to probe nanoscale electronic properties of photocatalytic materials, which will drive breakthroughs in the design of novel photocatalytic systems and advance the fundamental understanding of material properties.

ABACC ten years applying safeguards

International Nuclear Information System (INIS)

Palacios, Elias

2001-01-01

The Argentinian-Brazilian Agency for Accounting and Control of nuclear special materials has been in operations for ten years. The rational behind the creation and the work performed by the Agency during the last decade is described. (author)

EEG Correlates of Ten Positive Emotions.

Science.gov (United States)

Hu, Xin; Yu, Jianwen; Song, Mengdi; Yu, Chun; Wang, Fei; Sun, Pei; Wang, Daifa; Zhang, Dan

2017-01-01

Compared with the well documented neurophysiological findings on negative emotions, much less is known about positive emotions. In the present study, we explored the EEG correlates of ten different positive emotions (joy, gratitude, serenity, interest, hope, pride, amusement, inspiration, awe, and love). A group of 20 participants were invited to watch 30 short film clips with their EEGs simultaneously recorded. Distinct topographical patterns for different positive emotions were found for the correlation coefficients between the subjective ratings on the ten positive emotions per film clip and the corresponding EEG spectral powers in different frequency bands. Based on the similarities of the participants' ratings on the ten positive emotions, these emotions were further clustered into three representative clusters, as 'encouragement' for awe, gratitude, hope, inspiration, pride, 'playfulness' for amusement, joy, interest, and 'harmony' for love, serenity. Using the EEG spectral powers as features, both the binary classification on the higher and lower ratings on these positive emotions and the binary classification between the three positive emotion clusters, achieved accuracies of approximately 80% and above. To our knowledge, our study provides the first piece of evidence on the EEG correlates of different positive emotions.

Using TENS for pain control: the state of the evidence

Science.gov (United States)

Vance, Carol GT; Dailey, Dana L; Rakel, Barbara A; Sluka, Kathleen A

2014-01-01

Summary Transcutaneous electrical nerve stimulation (TENS) is a nonpharmacological intervention that activates a complex neuronal network to reduce pain by activating descending inhibitory systems in the central nervous system to reduce hyperalgesia. The evidence for TENS efficacy is conflicting and requires not only description but also critique. Population-specific systemic reviews and meta-analyses are emerging, indicating both HF and LF TENS being shown to provide analgesia, specifically when applied at a strong, nonpainful intensity. The purpose of this article is to provide a critical review of the latest basic science and clinical evidence for TENS. Additional research is necessary to determine if TENS has effects specific to mechanical stimuli and/or beyond reduction of pain and will improve activity levels, function and quality of life. PMID:24953072

"Take ten minutes": a dedicated ten minute medication review reduces polypharmacy in the elderly.

LENUS (Irish Health Repository)

Walsh, E K

2012-02-01

Multiple and inappropriate medications are often the cause for poor health status in the elderly. Medication reviews can improve prescribing. This study aimed to determine if a ten minute medication review by a general practitioner could reduce polypharmacy and inappropriate prescribing in elderly patients. A prospective, randomised study was conducted. Patients over the age of 65 (n = 50) underwent a 10-minute medication review. Inappropriate medications, dosage errors, and discrepancies between prescribed versus actual medication being consumed were recorded. A questionnaire to assess satisfaction was completed following review. The mean number of medications taken by patients was reduced (p < 0.001). A medication was stopped in 35 (70%) patients. Inappropriate medications were detected in 27 (54%) patients and reduced (p < 0.001). Dose errors were detected in 16 (32%). A high level of patient satisfaction was reported. A ten minute medication review reduces polypharmacy, improves prescribing and is associated with high levels of patient satisfaction.

"Take ten minutes": a dedicated ten minute medication review reduces polypharmacy in the elderly.

LENUS (Irish Health Repository)

Walsh, E K

2010-09-01

Multiple and inappropriate medications are often the cause for poor health status in the elderly. Medication reviews can improve prescribing. This study aimed to determine if a ten minute medication review by a general practitioner could reduce polypharmacy and inappropriate prescribing in elderly patients. A prospective, randomised study was conducted. Patients over the age of 65 (n = 50) underwent a 10-minute medication review. Inappropriate medications, dosage errors, and discrepancies between prescribed versus actual medication being consumed were recorded. A questionnaire to assess satisfaction was completed following review. The mean number of medications taken by patients was reduced (p < 0.001). A medication was stopped in 35 (70%) patients. Inappropriate medications were detected in 27 (54%) patients and reduced (p < 0.001). Dose errors were detected in 16 (32%). A high level of patient satisfaction was reported. A ten minute medication review reduces polypharmacy, improves prescribing and is associated with high levels of patient satisfaction.

Ten Tips for Parents to Help Their Children Avoid Teen Pregnancy

Science.gov (United States)

... we do » Resource library » Ten tips for parents Ten Tips for Parents to Help Their Children Avoid Teen Pregnancy Publication Created with Sketch. Ten Tips for Parents to Help Their Children Avoid ...

Magnetoacoustic Waves and the Kelvin-Helmholtz Instability in a Steady Asymmetric Slab. I: The Effects of Varying Density Ratios

Science.gov (United States)

Barbulescu, M.; Erdélyi, R.

2018-06-01

Recent observations have shown that bulk flow motions in structured solar plasmas, most evidently in coronal mass ejections (CMEs), may lead to the formation of Kelvin-Helmholtz instabilities (KHIs). Analytical models are thus essential in understanding both how the flows affect the propagation of magnetohydrodynamic (MHD) waves, and what the critical flow speed is for the formation of the KHI. We investigate both these aspects in a novel way: in a steady magnetic slab embedded in an asymmetric environment. The exterior of the slab is defined as having different equilibrium values of the background density, pressure, and temperature on either side. A steady flow and constant magnetic field are present in the slab interior. Approximate solutions to the dispersion relation are obtained analytically and classified with respect to mode and speed. General solutions and the KHI thresholds are obtained numerically. It is shown that, generally, both the KHI critical value and the cut-off speeds for magnetoacoustic waves are lowered by the external asymmetry.

Reflux and Belching After 270 Degree Versus 360 Degree Laparoscopic Posterior Fundoplication

NARCIS (Netherlands)

Broeders, Joris A.; Bredenoord, Albert J.; Hazebroek, Eric J.; Broeders, Ivo A.; Gooszen, Hein G.; Smout, André J.

2012-01-01

Objective: To investigate differences in effects of 270 degrees (270 degrees LPF) and 360 degrees laparoscopic posterior fundoplication (360 degrees LPF) on reflux characteristics and belching. Background: Three hundred sixty degrees LPF greatly reduces the ability of the stomach to vent ingested

Chernobyl ten years after

International Nuclear Information System (INIS)

1996-01-01

The accident in the fourth reactor plant in Chernobyl in Ukraine occurred ten years years ago, caused the death of 31 people while the health consequences have turned out to be difficult to assess. This review describes the accident, its consequences and effects to health, studies carried out at the present state as well as the comparison with the other accidents and disaster. (author)

ANALGETSKI UCINAK TRANSAKUTNE ELEKTRICNE NERVNE STIMULACIJE (TENS)

OpenAIRE

ĆURKOVIĆ, B.

1984-01-01

Transkutana električna nervna stimulacija. (TENS) danas je široko prihvaćen terapijski postupak za suzbijanje boli. Način njezina djelovanja nije još jasno definiran, premda se većina autora priklanja centralnom mehranizmu smanjenja boli. Rezultati, u literaturi, variraju od nesignifikantno boljeg učinka od placeba do 95°/o dobrog analgetskog djelovanja. U Zavodu za reumatske bolesti i rehabilitaciju Kliničkog bolničkog centra, Zagreb, evaluiran je učinak TENS-a u bolesnika s križ...

Long-term stability of morphine hydrochloride in 0.9% NaCl infusion polyolefin bags after freeze-thaw treatment and in polypropylene syringes at 5 degrees C + 3 degrees C.

Science.gov (United States)

Hecq, J-D; Godet, M; Gillet, P; Jamart, J; Galanti, L

2014-01-01

The aim of this study was to investigate the long-term stability of morphine hydrochloride in 0.9% NaCI infusion polyolefin bags and polypropylene syringes after storage at 5 degrees C + 3 degrees C and to evaluate the influence of initial freezing and microwave thawing on this stability. Ten polyolefin bags and five polypropylene syringes containing 100 mL of 1 mg/mL of morphine hydrochloride solution in 0.9% NaCI were prepared under aseptic conditions. Five polyolefin bags were frozen at -20 degrees C for 90 days before storage. Immediately after the preparation and after thawing, 2 mL of each bag were withdrawn for the initial concentration measurements. All polyolefin bags and polypropylene syringes were then refrigerated at 5 degrees C + 3 degrees C for 58 days during which the morphine concentrations were measured periodically by high-performance liquid chromatography using a reversed-phase column, naloxone as internal standard, a mobile phase consisting of 5% acetonitrile and 95% of KH2PO4 buffer (pH 3.50), and detection with diode array detector at 254 nm. Visual and microscopic observations and spectrophotometric and pH measurements were also performed. Solutions were considered stable if the concentration remained superior to 90% of the initial concentration. The degradation products peaks were not quantitatively significant and were resolved from the native drug. Polyolefin bag and polypropylene syringe solutions were stable when stored at 5 degrees C + 3 degrees C during these 58 days. No color change or precipitation in the solutions was observed. The physical stability was confirmed by visual, microscopic, and spectrophotometric inspection. There was no significant change in pH during storage. Freezing and microwave thawing didn't influence the infusion stability. Morphine hydrochloride infusions may be prepared in advance by centralized intravenous additive service, frozen in polyolefin bags, and microwave thawed before storage under refrigeration

Mediation of parental educational level on fruit and vegetable intake among schoolchildren in ten European countries.

Science.gov (United States)

Lehto, Elviira; Ray, Carola; Te Velde, Saskia; Petrova, Stefka; Duleva, Vesselka; Krawinkel, Michael; Behrendt, Isabel; Papadaki, Angeliki; Kristjansdottir, Asa; Thorsdottir, Inga; Yngve, Agneta; Lien, Nanna; Lynch, Christel; Ehrenblad, Bettina; Vaz de Almeida, Maria Daniel; Ribic, Cirila Hlastan; Simčic, Irena; Roos, Eva

2015-01-01

To examine which factors act as mediators between parental educational level and children's fruit and vegetable (F&V) intake in ten European countries. Cross-sectional data were collected in ten European countries participating in the PRO GREENS project (2009). Schoolchildren completed a validated FFQ about their daily F&V intake and filled in a questionnaire about availability of F&V at home, parental facilitation of F&V intake, knowledge of recommendations about F&V intake, self-efficacy to eat F&V and liking for F&V. Parental educational level was determined from a questionnaire given to parents. The associations were examined with multilevel mediation analyses. Schools in Bulgaria, Finland, Germany, Greece, Iceland, the Netherlands, Norway, Portugal, Slovenia and Sweden. Eleven-year-old children (n 8159, response rate 72%) and their parents. In five of the ten countries, children with higher educated parents were more likely to report eating fruits daily. This association was mainly mediated by knowledge but self-efficacy, liking, availability and facilitation also acted as mediators in some countries. Parents' education was positively associated with their children's daily vegetable intake in seven countries, with knowledge and availability being the strongest mediators and self-efficacy and liking acting as mediators to some degree. Parental educational level correlated positively with children's daily F&V intake in most countries and the pattern of mediation varied among the participating countries. Future intervention studies that endeavour to decrease the educational-level differences in F&V intake should take into account country-specific features in the relevant determinants of F&V intake.

"How much will I get charged for this?" Patient charges for top ten diagnoses in the emergency department.

Directory of Open Access Journals (Sweden)

Nolan Caldwell

Full Text Available We examined the charges, their variability, and respective payer group for diagnosis and treatment of the ten most common outpatient conditions presenting to the Emergency department (ED.We conducted a cross-sectional study of the 2006-2008 Medical Expenditure Panel Survey. Analysis was limited to outpatient visits with non-elderly, adult (years 18-64 patients with a single discharge diagnosis.We studied 8,303 ED encounters, representing 76.6 million visits. Median charges ranged from $740 (95% CI $651-$817 for an upper respiratory infection to $3437 (95% CI $2917-$3877 for a kidney stone. The median charge for all ten outpatient conditions in the ED was $1233 (95% CI $1199- $1268, with a high degree of charge variability. All diagnoses had an interquartile range (IQR greater than $800 with 60% of IQRs greater than $1550.Emergency department charges for common conditions are expensive with high charge variability. Greater acute care charge transparency will at least allow patients and providers to be aware of the emergency department charges patients may face in the current health care system.

Modeling ramp-hold indentation measurements based on Kelvin-Voigt fractional derivative model

Science.gov (United States)

Zhang, Hongmei; zhe Zhang, Qing; Ruan, Litao; Duan, Junbo; Wan, Mingxi; Insana, Michael F.

2018-03-01

Interpretation of experimental data from micro- and nano-scale indentation testing is highly dependent on the constitutive model selected to relate measurements to mechanical properties. The Kelvin-Voigt fractional derivative model (KVFD) offers a compact set of viscoelastic features appropriate for characterizing soft biological materials. This paper provides a set of KVFD solutions for converting indentation testing data acquired for different geometries and scales into viscoelastic properties of soft materials. These solutions, which are mostly in closed-form, apply to ramp-hold relaxation, load-unload and ramp-load creep-testing protocols. We report on applications of these model solutions to macro- and nano-indentation testing of hydrogels, gastric cancer cells and ex vivo breast tissue samples using an atomic force microscope (AFM). We also applied KVFD models to clinical ultrasonic breast data using a compression plate as required for elasticity imaging. Together the results show that KVFD models fit a broad range of experimental data with a correlation coefficient typically R 2  >  0.99. For hydrogel samples, estimation of KVFD model parameters from test data using spherical indentation versus plate compression as well as ramp relaxation versus load-unload compression all agree within one standard deviation. Results from measurements made using macro- and nano-scale indentation agree in trend. For gastric cell and ex vivo breast tissue measurements, KVFD moduli are, respectively, 1/3-1/2 and 1/6 of the elasticity modulus found from the Sneddon model. In vivo breast tissue measurements yield model parameters consistent with literature results. The consistency of results found for a broad range of experimental parameters suggest the KVFD model is a reliable tool for exploring intrinsic features of the cell/tissue microenvironments.

Solving Business Problems Together Case: A Master's Degree Programme in Finland

Directory of Open Access Journals (Sweden)

Maria Jakubik

2017-08-01

Full Text Available This descriptive, single, intrinsic case study seeks to answer the following questions: Why should business practitioners and educators work together in solving business problems? How are the business problems of companies handled in a master's degree programme in Finland? The case study is based on multiple sources of documents collected and developed during the ten years of the programme. It demonstrates that solving authentic business problems in a learning community of business practitioners, i.e. students, as well as educators, i.e. teachers and thesis advisors, leads to solutions that satisfy practitioners, educators, and the business community. This case is an example of how solving business problems together contributes to the better performance of businesses and a better society in Finland.

How the Big Ten West Was Won: Football Recruiting

Directory of Open Access Journals (Sweden)

Diehl Kevin A.

2017-06-01

Full Text Available The paper analyses the 2017 Big Ten West Division football cycle models recruiting. The top ten recruit scores [(Rivals.com * 100 + [100 (outside surrounding; 75 (surrounding] + extra credit walk-ons (100; 75] allow proper ranking: Iowa, Nebraska, Wisconsin, Northwestern, Illinois, Minnesota, and Purdue.

High-resolution noncontact AFM and Kelvin probe force microscopy investigations of self-assembled photovoltaic donor–acceptor dyads

Directory of Open Access Journals (Sweden)

Benjamin Grévin

2016-06-01

Full Text Available Self-assembled donor–acceptor dyads are used as model nanostructured heterojunctions for local investigations by noncontact atomic force microscopy (nc-AFM and Kelvin probe force microscopy (KPFM. With the aim to probe the photo-induced charge carrier generation, thin films deposited on transparent indium tin oxide substrates are investigated in dark conditions and upon illumination. The topographic and contact potential difference (CPD images taken under dark conditions are analysed in view of the results of complementary transmission electron microscopy (TEM experiments. After in situ annealing, it is shown that the dyads with longer donor blocks essentially lead to standing acceptor–donor lamellae, where the acceptor and donor groups are π-stacked in an edge-on configuration. The existence of strong CPD and surface photo-voltage (SPV contrasts shows that structural variations occur within the bulk of the edge-on stacks. SPV images with a very high lateral resolution are achieved, which allows for the resolution of local photo-charging contrasts at the scale of single edge-on lamella. This work paves the way for local investigations of the optoelectronic properties of donor–acceptor supramolecular architectures down to the elementary building block level.

2012 Ten-year scheme of network development

International Nuclear Information System (INIS)

2012-01-01

RTE, an independent subsidiary of EDF, is the French electricity transmission system operator. It is a public service company responsible for operating, maintaining and developing the high and extra high voltage network. It guarantees the reliability and proper operation of the power network. RTE transports electricity between electricity suppliers (French and European) and consumers, whether they are electricity distributors or industrial consumers directly connected to the transmission system. The mission of RTE is to balance the electricity supply and demand in real time. With the support of the government authorities, RTE prepares a ten-year scheme of network development in France; This document presents the main electricity transport infrastructures to foresee within the ten coming years and lists the network development investments which must be realised and implemented within 3 years. The document is updated each year and comes to complement at the national level the European ten year network development plan (TYNDP) and the European regional plans as provided for in the 2009/72/CE European directive

Ten-year scheme of network development - 2011

International Nuclear Information System (INIS)

2011-01-01

RTE, an independent subsidiary of EDF, is the French electricity transmission system operator. It is a public service company responsible for operating, maintaining and developing the high and extra high voltage network. It guarantees the reliability and proper operation of the power network. RTE transports electricity between electricity suppliers (French and European) and consumers, whether they are electricity distributors or industrial consumers directly connected to the transmission system. The mission of RTE is to balance the electricity supply and demand in real time. With the support of the government authorities, RTE prepares a ten-year scheme of network development in France; This document presents the main electricity transport infrastructures to foresee within the ten coming years and lists the network development investments which must be realised and implemented within 3 years. The document is updated each year and comes to complement at the national level the European ten year network development plan (TYNDP) and the European regional plans as provided for in the 2009/72/CE European directive

Top-Ten IT Issues: 2009

Science.gov (United States)

Agee, Anne Scrivener; Yang, Catherine

2009-01-01

This article presents the top-ten IT-related issues in terms of strategic importance to the institution, as revealed by the tenth annual EDUCAUSE Current Issues Survey. These IT-related issues include: (1) Funding IT; (2) Administrative/ERP Information Systems; (3) Security; (4) Infrastructure/Cyberinfrastructure; (5) Teaching and Learning with…

Nuclear-related training and education offered by academic institutions (less than baccalaureate degree) (preliminary)

International Nuclear Information System (INIS)

Howard, L.

1981-11-01

This study presents the results of a survey of academic institutions offering nuclear-related training and education at the less than baccalaureate degree level. The scope of the survey includes only those programs which have a nuclear power industry application, and excludes all programs which are affiliated with nuclear medicine. The survey instrument was distributed by the Institute of Nuclear Power Operations to 262 academic institutions. The survey universe was compiled from a number of publications that listed nuclear-related academic programs. Since the initial mailing in May 1981, ten of the institutions have been determined to no longer exist and eight other listings have been identified as duplications, thus reducing the universe to 244 institutions. Fifty-five percent of the survey population (134 institutions) responded to the questionnaire, of which 45 percent (109) were out of the survey scope and 10 percent (25) indicated they offered less than baccalaureate degree, nuclear-related programs

The Degree Cycle

DEFF Research Database (Denmark)

Wood, Johanna

2016-01-01

, empirical data relevant to the development of the degree adverb function is presented and possible relevant constructions identified. It is argued that the degree adverb function of that possibly occurs later than the historical dictionaries indicate. The degree adverb function of this is challenging...

Investigation of uncertainty components in Coulomb blockade thermometry

International Nuclear Information System (INIS)

Hahtela, O. M.; Heinonen, M.; Manninen, A.; Meschke, M.; Savin, A.; Pekola, J. P.; Gunnarsson, D.; Prunnila, M.; Penttilä, J. S.; Roschier, L.

2013-01-01

Coulomb blockade thermometry (CBT) has proven to be a feasible method for primary thermometry in every day laboratory use at cryogenic temperatures from ca. 10 mK to a few tens of kelvins. The operation of CBT is based on single electron charging effects in normal metal tunnel junctions. In this paper, we discuss the typical error sources and uncertainty components that limit the present absolute accuracy of the CBT measurements to the level of about 1 % in the optimum temperature range. Identifying the influence of different uncertainty sources is a good starting point for improving the measurement accuracy to the level that would allow the CBT to be more widely used in high-precision low temperature metrological applications and for realizing thermodynamic temperature in accordance to the upcoming new definition of kelvin

Investigation of uncertainty components in Coulomb blockade thermometry

Energy Technology Data Exchange (ETDEWEB)

Hahtela, O. M.; Heinonen, M.; Manninen, A. [MIKES Centre for Metrology and Accreditation, Tekniikantie 1, 02150 Espoo (Finland); Meschke, M.; Savin, A.; Pekola, J. P. [Low Temperature Laboratory, Aalto University, Tietotie 3, 02150 Espoo (Finland); Gunnarsson, D.; Prunnila, M. [VTT Technical Research Centre of Finland, Tietotie 3, 02150 Espoo (Finland); Penttilä, J. S.; Roschier, L. [Aivon Oy, Tietotie 3, 02150 Espoo (Finland)

2013-09-11

Coulomb blockade thermometry (CBT) has proven to be a feasible method for primary thermometry in every day laboratory use at cryogenic temperatures from ca. 10 mK to a few tens of kelvins. The operation of CBT is based on single electron charging effects in normal metal tunnel junctions. In this paper, we discuss the typical error sources and uncertainty components that limit the present absolute accuracy of the CBT measurements to the level of about 1 % in the optimum temperature range. Identifying the influence of different uncertainty sources is a good starting point for improving the measurement accuracy to the level that would allow the CBT to be more widely used in high-precision low temperature metrological applications and for realizing thermodynamic temperature in accordance to the upcoming new definition of kelvin.

RE-SONANCE--I -De-ce-mber

Indian Academy of Sciences (India)

to their having a high density of free, mobile electrons. One problem with this ..... neighbour moments (dipole-dipole interaction) is of the order of a few degrees Kelvin: .... Metal. Insulator Transitions: One idea basic to our thinking of electrons in ...

Fabrication of ten-fold photonic quasicrystalline structures

Directory of Open Access Journals (Sweden)

XiaoHong Sun

2015-05-01

Full Text Available Compared to periodic crystals, quasicrystals have higher point group symmetry and are more favorable in achieving complete band-gaps. In this report, a top-cut prism interferometer is designed to fabricate ten-fold photonic quasicrystalline structures. By optimizing the exposing conditions and material characteristics, appropriate quasicrystals have been obtained in the SU8 photoresist films. Atomic Force Microscopy and laser diffraction are used to characterize the fabricated structures. The measurement results show the consistence between the theoretical design and experiments. This will provide guidance for the large-area and fast production of ten-fold quasicrystalline structures with high quality.

Surface potential measurement on contact resistance of amorphous-InGaZnO thin film transistors by Kelvin probe force microscopy

Science.gov (United States)

Han, Zhiheng; Xu, Guangwei; Wang, Wei; Lu, Congyan; Lu, Nianduan; Ji, Zhuoyu; Li, Ling; Liu, Ming

2016-07-01

Contact resistance plays an important role in amorphous InGaZnO (a-IGZO) thin film transistors (TFTs). In this paper, the surface potential distributions along the channel have been measured by using Kelvin probe force microscopy (KPFM) on operating a-IGZO TFTs, and sharp potential drops at the edges of source and drain were observed. The source and drain contact resistances can be extracted by dividing sharp potential drops with the corresponding drain to source current. It is found that the contact resistances could not be neglected compared with the whole channel resistances in the a-IGZO TFT, and the contact resistances decrease remarkably with increasing gate biased voltage. Our results suggest that the contact resistances can be controlled by tuning the gate biased voltage. Moreover, a transition from gradual channel approximation to space charge region was observed through the surface potential map directly when TFT operating from linear regime to saturation regime.

Preparing Science-Trained Professionals for the Biotechnology Industry: A Ten-Year Perspective on a Professional Science Master’s Program

Directory of Open Access Journals (Sweden)

Paul T. Hamilton

2012-02-01

Full Text Available The biotechnology industry has a need for business-savvy scientists; however, this is not the way scientists are traditionally trained at universities and colleges. To address this need, universities have developed Professional Science Master’s (PSM degree programs that offer advanced training in a technical field along with professional skills development through team-based projects and internships. Nearly ten years ago, the Department of Microbiology at NCSU started a PSM program in Microbial Biotechnology (MMB. This article provides an overview of the MMB program, and shares some of the lessons that we have learned.

Ten into four won't go

International Nuclear Information System (INIS)

Freedman, D.Z.; West, P.C.

1989-01-01

It is shown that nontrivial spontaneous compactification of ten-dimensional N = 1 supergravity with or without Yang-Mills matter is not possible unless maximal symmetry (i.e. Lorentz invariance) is violated in the four-dimensional spacetime

Critical Studies on Men in Ten European Countries

DEFF Research Database (Denmark)

Pringle, Keith; Hearn, Jeff (and 13 other network partners)

2002-01-01

This article is one the work of The European Research Network on Men in Europe project “The Social Problem and Societal Problematization of Men and Masculinities” (2000-2003), funded by the European Commission. The Network comprises women and men researchers with range of disciplinary backgrounds...... of statistical sources on men's practices in the ten countries, are presented. This is the second of four articles reviewing critical studies on men in the ten countries through different methods and approaches....

Nonresponse Error in Mail Surveys: Top Ten Problems

Directory of Open Access Journals (Sweden)

Jeanette M. Daly

2011-01-01

Full Text Available Conducting mail surveys can result in nonresponse error, which occurs when the potential participant is unwilling to participate or impossible to contact. Nonresponse can result in a reduction in precision of the study and may bias results. The purpose of this paper is to describe and make readers aware of a top ten list of mailed survey problems affecting the response rate encountered over time with different research projects, while utilizing the Dillman Total Design Method. Ten nonresponse error problems were identified, such as inserter machine gets sequence out of order, capitalization in databases, and mailing discarded by postal service. These ten mishaps can potentiate nonresponse errors, but there are ways to minimize their frequency. Suggestions offered stem from our own experiences during research projects. Our goal is to increase researchers' knowledge of nonresponse error problems and to offer solutions which can decrease nonresponse error in future projects.

Design and Evaluation on the Mobile Application of Transcutaneous Electrical Nerve Stimulation (TENS).

Science.gov (United States)

Cheng, Ching-Lung; Lee, Li-Hui; Cheng, Yu-Ting

2017-01-01

This study aims to design a transcutaneous electrical nerve stimulation Application (TENS App) according to the suggestions from potential users. To the best of our knowledge, this is the first App including meridian and acupoints for TENS. After its development, there are eight participants recruited for evaluating the usability. Despite two out of eight users reporting that the typical TENS system requires lower cost and has better functionality than TENS App, the results show that almost seventy percent of participants have a better perception of TENS App on price, functionality, convenience, operational ability, and quality. However, participants still reported concerns about the safety issue of adopting TENS App. Therefore, for people who are the first time or unfamiliar with TENS App, instructions from occupational or physical therapists are recommended. We conclude that by using TENS App, users can not only use the portable electrotherapy devices at anyplace, but also reduce their outpatient visits.

Transcutaneous electrical nerve stimulation (TENS) for chronic low-back pain.

Science.gov (United States)

Khadilkar, A; Milne, S; Brosseau, L; Robinson, V; Saginur, M; Shea, B; Tugwell, P; Wells, G

2005-07-20

Chronic low-back pain (LBP) affects a significant proportion of the population. Transcutaneous electrical nerve stimulation (TENS) was introduced more than 30 years ago as an adjunct to the pharmacological management of pain. However, despite its widespread use, the usefulness of TENS in chronic LBP is still controversial. The aim of this systematic review was to determine the effectiveness of TENS in the management of chronic LBP. We searched the Cochrane Central Register of Controlled Trials (Issue 2, 2005), MEDLINE, EMBASE and PEDro up to April 1, 2005. Only randomized controlled clinical trials (RCTs) evaluating the effect of TENS on chronic LBP were included. Abstracts were excluded unless further data could be obtained from the authors. Two reviewers independently selected trials and extracted data using predetermined forms. Heterogeneity was tested with Cochrane's Q test. A fixed effect model was used throughout for calculating continuous variables, except where heterogeneity existed, in which case, a random effects model was used. Results are presented as weighted mean differences (WMD) with 95% confidence intervals (95% CI), where the difference between the treated and control groups was weighted by the inverse of the variance. Standardized mean differences (SMD) were calculated by dividing the difference between the treated and control by the baseline variance. SMD were used when different scales were used to measure the same concept. Dichotomous outcomes were analyzed with odds ratios. The only two RCTs (175 patients) meeting eligibility criteria differed in study design, methodological quality, inclusion and exclusion criteria, type and method of TENS application, treatment schedule, co-interventions and final outcomes. In one RCT, TENS produced significantly greater pain relief than the placebo control. However, in the other RCT, no statistically significant differences between treatment and control groups were shown for multiple outcome measures. Pre

Validation of Vibro-Impact Force Models by Numerical Simulation, Perturbation Methods and Experiments

DEFF Research Database (Denmark)

de Souza Reboucas, Geraldo Francisco; Santos, Ilmar; Thomsen, Jon Juel

2017-01-01

The frequency response of a single degree of freedom vibro-impact oscillator is analyzed using Harmonic Linearization, Averaging and Numeric Simulation, considering three different impact force models: one given by a piecewise-linear function (Kelvin-Voigt model), another by a high-order power...

Annealing of neutron-irradiated vanadium containing oxygen

International Nuclear Information System (INIS)

Foster, R.E.

1979-01-01

A study to clarify the role of interstitial oxygen in irradiated vanadium by measuring the activation energy of the 0.2 T/sub m/ recovery stage in well-characterized samples, where T/sub m/ is the melting temperature in degrees Kelvin, is described

An examination of the factors related to women's degree attainment and career goals in science, technology, and mathematics

Science.gov (United States)

Nitopi, Marie

During the last 30 years, women have made tremendous advances in educational attainment especially in post-secondary education. Despite these advances, recent researchers have revealed that women continue to remain underrepresented in attainment of graduate degrees in the sciences. The researcher's purpose in this study was to extend previous research and to develop a model of variables that significantly contribute to persistence in and attainment of a graduate degree and an eventual career in the science, mathematics, or technology professions. Data were collected from the Baccalaureate and Beyond Longitudinal Study (B&B:93/03). Variables in the categories of demographics, academics, finances, values and attitudes toward educational experiences, and future employment were analyzed by t tests and logistic regressions to determine gender differences in graduate degree attainment and career goals by male and female who majored in science, technology and mathematics. Findings supported significant gender differences in expectations for a graduate degree, age at baccalaureate degree attainment, number of science and engineering credits taken, and the value of faculty interactions. Father's education had a significant effect on degree attainment. Women and men had similar expectations at the beginning of their educational career, but women tended to fall short of their degree expectations ten years later. A large proportion of women dropped out of the science pipeline by choosing different occupations after degree completion. Additionally, women earned fewer science and math credits than men. The professions of science and technology are crucial for the nation's economic growth and competitiveness; therefore, additional researchers should focus on retaining both men and women in the STEM professions.

Time dependence of the natural passivation process on AISI 304 in an alkaline medium: Atomic force microscopy and scanning Kelvin probe force microscopy as additional tools to electrochemical impedance spectroscopy

Science.gov (United States)

Benaioun, N. E.; Maafa, I.; Florentin, A.; Denys, E.; Hakiki, N. E.; Moulayat, N.; Bubendorff, J. L.

2018-04-01

Thin surface films formed on AISI 304 samples in an alkaline solution of pH = 13 are studied by atomic force microscopy (AFM), scanning Kelvin probe force microscopy (SKPFM) and electrochemical impedance spectroscopy (EIS) as a function of immersion time. The results reveal that changes on EIS diagrams correspond to topographical modifications on the sample surface as shown by AFM. Both techniques are therefore complementary. The oxide layer is chemically homogenous as shown by SKPFM imaging and our ultra-thin passive layer is an efficient barrier against corrosion.

Four-Spacecraft Magnetic Curvature and Vorticity Analyses on Kelvin-Helmholtz Waves in MHD Simulations

Science.gov (United States)

Kieokaew, Rungployphan; Foullon, Claire; Lavraud, Benoit

2018-01-01

Four-spacecraft missions are probing the Earth's magnetospheric environment with high potential for revealing spatial and temporal scales of a variety of in situ phenomena. The techniques allowed by these four spacecraft include the calculation of vorticity and the magnetic curvature analysis (MCA), both of which have been used in the study of various plasma structures. Motivated by curved magnetic field and vortical structures induced by Kelvin- Helmholtz (KH) waves, we investigate the robustness of the MCA and vorticity techniques when increasing (regular) tetrahedron sizes, to interpret real data. Here for the first time, we test both techniques on a 2.5-D MHD simulation of KH waves at the magnetopause. We investigate, in particular, the curvature and flow vorticity across KH vortices and produce time series for static spacecraft in the boundary layers. The combined results of magnetic curvature and vorticity further help us to understand the development of KH waves. In particular, first, in the trailing edge, the magnetic curvature across the magnetopause points in opposite directions, in the wave propagation direction on the magnetosheath side and against it on the magnetospheric side. Second, the existence of a "turnover layer" in the magnetospheric side, defined by negative vorticity for the duskside magnetopause, which persists in the saturation phase, is reminiscent of roll-up history. We found significant variations in the MCA measures depending on the size of the tetrahedron. This study lends support for cross-scale observations to better understand the nature of curvature and its role in plasma phenomena.

Evaluation of quality of mango cultivar Tommy Atkins radiated with greater degree of maturity

Energy Technology Data Exchange (ETDEWEB)

Silva, Josenilda M. da, E-mail: jmnilda@cnen.gov.br [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil); Santos, Marilia C.G. dos; Maciel, Maria Ines S., E-mail: marines@ufrpe.br [Universidade Federal Rural de Pernambuco (UFRPE), Recife, PE (Brazil); Villar, Heldio P., E-mail: hpvillar@cnen.gov.br [Escola Politecnica de Pernambuco, Recife, PE (Brazil)

2011-07-01

The effects of ionizing radiation at doses of 0.5 and 1.0 kGy were evaluated in mango cultivar Tommy Atkins when harvested at maturation stage showing yellow flesh and skin color more red than green, representing four degree of maturation at commercial scale. The fruits were stored for 21 days at 12 degree C and sensory evaluated after that period as its external appearance, internal appearance, acidic taste, sweet taste, mellow flavor, aroma, texture and succulence of the flesh, by a team of ten trained judges. Physic chemical analysis of the main characteristics of fruits quality were also performed in the pulp at the end of storage. The results of sensory analysis revealed that the doses used did not damaged the sensory characteristics of mango fruit and that they received a dose of 0.5 kGy showed higher acceptance for most sensory attributes evaluated. The physic chemical characteristics showed no significant differences between the doses, except the amount of ascorbic acid that decreased progressively with increasing doses. Application of this method is viable for mango cultivar Tommy Atkins when taken with a higher degree of maturity and was safe for the external market and sensory acceptable. (author)

Evaluation of quality of mango cultivar Tommy Atkins radiated with greater degree of maturity

International Nuclear Information System (INIS)

Silva, Josenilda M. da; Santos, Marilia C.G. dos; Maciel, Maria Ines S.; Villar, Heldio P.

2011-01-01

The effects of ionizing radiation at doses of 0.5 and 1.0 kGy were evaluated in mango cultivar Tommy Atkins when harvested at maturation stage showing yellow flesh and skin color more red than green, representing four degree of maturation at commercial scale. The fruits were stored for 21 days at 12 degree C and sensory evaluated after that period as its external appearance, internal appearance, acidic taste, sweet taste, mellow flavor, aroma, texture and succulence of the flesh, by a team of ten trained judges. Physic chemical analysis of the main characteristics of fruits quality were also performed in the pulp at the end of storage. The results of sensory analysis revealed that the doses used did not damaged the sensory characteristics of mango fruit and that they received a dose of 0.5 kGy showed higher acceptance for most sensory attributes evaluated. The physic chemical characteristics showed no significant differences between the doses, except the amount of ascorbic acid that decreased progressively with increasing doses. Application of this method is viable for mango cultivar Tommy Atkins when taken with a higher degree of maturity and was safe for the external market and sensory acceptable. (author)

Wideband 360 degrees microwave photonic phase shifter based on slow light in semiconductor optical amplifiers.

Science.gov (United States)

Xue, Weiqi; Sales, Salvador; Capmany, José; Mørk, Jesper

2010-03-15

In this work we demonstrate for the first time, to the best of our knowledge, a continuously tunable 360 degrees microwave phase shifter spanning a microwave bandwidth of several tens of GHz (up to 40 GHz). The proposed device exploits the phenomenon of coherent population oscillations, enhanced by optical filtering, in combination with a regeneration stage realized by four-wave mixing effects. This combination provides scalability: three hybrid stages are demonstrated but the technology allows an all-integrated device. The microwave operation frequency limitations of the suggested technique, dictated by the underlying physics, are also analyzed.

Mid-term evaluation of ten National Research schools

DEFF Research Database (Denmark)

Gustafsson, Göran; Dahl, Hanne Marlene; Gustafsson, Christina

the scheme was launched, the Research Council has issued three calls for proposals and allocated grants to a total of 22 national research schools. Five were started up in 2009, ten in 2013 and seven in 2015. A Nordic scientific programme committee was appointed in 2013, with responsibility for assessing...... grant applications, monitoring the progress of the FORSKERSKOLER scheme and serving as the evaluation panel for the mid-term evaluation in 2013 and in 2016/2017. The task of the evaluation panel has been to: 1) evaluate the quality of and progress achieved by the ten research schools which were awarded...... funding in 2012 and launched in 2013; and 2) to provide recommendations as to whether funding should be continued to cover the full eight-year period or terminated after five years. Continued funding is recommended for all ten schools to cover the full eight-year period, according to the proposed budget...

Comparison of the refractive error changes among young children in ten years interval

Directory of Open Access Journals (Sweden)

Hai-Yan Li

2013-07-01

Full Text Available AIM: To compare the optometric examination results of myopic young children between those diagnosed in the period from 1998 to 2000 and those diagnosed in the period from 2008 to 2010; and to find out the causes of myopia and factors that worsen the condition, and suggest methods of its prevention and treatment.METHODS: This study was a retrospective case study. We randomly selected sample from out-patient department register of cases and divided them into two main groups, ‘ten year before group'(TYBG(1998/2000 year casesand ‘ten years later group'(2008/2010 year cases(TYLG. Each group was further subdivided into three sub-groups by age: under-six years old children group(CG, seven-twelve years old primary-school group(PSGand thirteen-eighteen years old middle-school group(MSG. The optometric examination results were statistically analyzed.RESULTS: The difference of the mean dioptre between the TYBG and TYLG was strongly statistically significant, also forward-lead trend of age when children suffered from myopia was found(P0.01. There was a significant increase of dioptre among PSG and MSG in TYLG compared to TYBG(PCONCLUSION: Our study shows that the age of getting myopia was forward lead, the dioptre increases by 1.00 degree and the prevalence of myopia is increasing gradually. This situation may due to the modern life style and changes of living standard of the population. Therefore, prevention of myopia should concentrate more on younger children at kindergarten and primary school stage students.

Degree distribution in discrete case

International Nuclear Information System (INIS)

Wang, Li-Na; Chen, Bin; Yan, Zai-Zai

2011-01-01

Vertex degree of many network models and real-life networks is limited to non-negative integer. By means of measure and integral, the relation of the degree distribution and the cumulative degree distribution in discrete case is analyzed. The degree distribution, obtained by the differential of its cumulative, is only suitable for continuous case or discrete case with constant degree change. When degree change is not a constant but proportional to degree itself, power-law degree distribution and its cumulative have the same exponent and the mean value is finite for power-law exponent greater than 1. -- Highlights: → Degree change is the crux for using the cumulative degree distribution method. → It suits for discrete case with constant degree change. → If degree change is proportional to degree, power-law degree distribution and its cumulative have the same exponent. → In addition, the mean value is finite for power-law exponent greater than 1.

Is TENS purely a placebo effect? A controlled study on chronic low back pain.

Science.gov (United States)

Marchand, S; Charest, J; Li, J; Chenard, J R; Lavignolle, B; Laurencelle, L

1993-07-01

Although high-frequency low-intensity transcutaneous electric nerve stimulation (TENS) has been extensively used to relieve low back pain, experimental studies of its effectiveness have yielded contradictory findings mainly due to methodological problems in pain evaluation and placebo control. In the present study, separate visual analog scales (VAS) were used to measure the sensory-discriminative and motivational-affective components of low back pain. Forty-two subjects were randomly assigned to 1 of 3 groups: TENS, placebo-TENS, and no treatment (control). In order to measure the short-term effect of TENS, VAS pain ratings were taken before and after each treatment session. Also, to measure long-term effects, patients rated their pain at home every 2 h throughout a 3-day period before and 1 week, 3 months and 6 months after the treatment sessions. In comparing the pain evaluations made immediately before and after each treatment session, TENS and placebo-TENS significantly reduced both the intensity and unpleasantness of chronic low back pain. TENS was significantly more efficient than placebo-TENS in reducing pain intensity but not pain unpleasantness. TENS also produced a significant additive effect over repetitive treatment sessions for pain intensity and relative pain unpleasantness. This additive effect was not found for placebo-TENS. When evaluated at home, pain intensity was significantly reduced more by TENS than placebo-TENS 1 week after the end of treatment, but not 3 months and 6 months later. At home evaluation of pain unpleasantness in the TENS group was never different from the placebo-TENS group.(ABSTRACT TRUNCATED AT 250 WORDS)

Ten out of ten for LHC decapole magnets

CERN Multimedia

2001-01-01

CERN's Albert Ijspeert (left) and Avinash Puntambekar of the Indian CAT laboratory with the ten Indian decapole magnets on the test bench. Tests will be carried out by the LHC-MTA group. A batch of 10 superconducting decapole magnets for the LHC has just arrived at CERN from India. These will be used to correct for slight imperfections in the dipole magnets that will steer proton beams around CERN's new accelerator. All magnets have slight imperfections in the fields they produce, and in the LHC dipoles these will be corrected for using sextupoles and decapoles. The sextupoles were the first LHC magnets to be given the production green-light following successful tests of pre-series magnets last year (Bulletin 21/2000, 22 May 2000). Now it is the turn of pre-series decapoles to go on trial at CERN. Of the LHC's 1232 dipole magnets, half will use sextupole correctors only and the other half will use both sextupoles and decapoles. That means that a total of 616 pairs of decapoles are needed. Like the sextupole...

[Very late but too early... prof. Angelo Chiavaro and the Italian degree in dentistry].

Science.gov (United States)

Eramo, Stefano; Bensi, Caterina; Belli, Stefano; Pagano, Stefano

2017-12-01

The birth of the Degree in Dentistry in Italy has been very troubled, and only in 1980 saw its effective implementation. Very "instructive" in this regard is the history on the establishment in 1924 (the period of the seizure of power by Fascism) of a "National School of Dentistry" at the University of Rome, which was withdrawn after only ten months. The biggest supporter and proponent of the School, Prof. Angelo Chiavaro, after a few years, was "punished" with the transfer from the University of Rome to that of Genoa. We present some brief notes on the biography of this courageous pioneer and the matter of which he was the protagonist.

Pickup Ion Dynamics in the Outer Heliosheath Associated with the Growth of Kelvin-Helmholtz Instability at the Heliopause

Science.gov (United States)

Tsubouchi, K.

2017-12-01

A discovery of "IBEX ribbon", localized bright emission of energetic neutral atoms, has brought new insights into the plasma environment of its source region beyond the heliosphere. It has been basically established that its geometrical property is associated with the local interstellar magnetic field draped on the heliopause, and pickup ions (PUIs) in the outer heliosheath (OHS) must be its primary source particles. Understanding the PUI dynamics in OHS more in detail is our motivation for this study. We performed two-dimensional hybrid simulations to evaluate the response of PUIs to the structural variation in the heliosheath. We assumed the simulation system such that the background plasma is hot solar wind in the inner heliosheath and cold interstellar plasma in OHS, and the directions of these flows are tangential to the heliopause. Such a situation leads to the growth of Kelvin-Helmholtz instability (KHI), where the plasma mixing and turbulence excitation takes place. We identified that non-stationarity and non-uniformity emerges in the PUI density structure in a specific energy range as KHI process advances. Relevance of these results to the expected observation like IBEX ribbon will be discussed.

Sensing the facet orientation in silver nano-plates using scanning Kelvin probe microscopy in air

Energy Technology Data Exchange (ETDEWEB)

Abdellatif, M.H. [Department of Nanostructures, Istituto Italiano di Tecnologia, via Morego 30, I-16163 Genova (Italy); Physics Department, National Research Center, Elbehoos st., 12622, Dokki, Giza (Egypt); Salerno, M., E-mail: marco.salerno@iit.it [Department of Nanophysics, Istituto Italiano di Tecnologia, via Morego 30, I-16163 Genova (Italy); Polovitsyn, Anatolii [Department of Nanochemistry, Istituto Italiano di Tecnologia, via Morego 30, I-16163 Genova (Italy); Dipartimentodi Fisica, Università di Genova, via Dodecaneso 33, I-16146 Genova (Italy); Marras, Sergio [Department of Nanochemistry, Istituto Italiano di Tecnologia, via Morego 30, I-16163 Genova (Italy); De Angelis, Francesco [Department of Nanostructures, Istituto Italiano di Tecnologia, via Morego 30, I-16163 Genova (Italy)

2017-05-01

Highlights: • The surface potential of drop cast nanocrystals was measured by SKPM in ambient air. • The nanocrystal facet work function was derived by theory. • By comparing theory and experiment we distinguished the nanocrystal facets. • Nanocrystal facet control is of practical interest for optoelectronic devices. - Abstract: The work function of nano-materials is important for a full characterization of their electronic properties. Because the band alignment, band bending and electronic noise are very sensitive to work function fluctuations, the dependence of the work function of nano-scale crystals on facet orientation can be a critical issue in optimizing optoelectronic devices based on these materials. We used scanning Kelvin probe microscopy to assess the local work function on samples of silver nano-plates at sub-micrometric spatial resolution. With the appropriate choice of the substrate and based on statistical analysis, it was possible to distinguish the surface potential of the different facets of silver nano-plates even if the measurements were done in ambient conditions without the use of vacuum. A phenomenological model was used to calculate the differences of facet work function of the silver nano-plates and the corresponding shift in Fermi level. This theoretical prediction and the experimentally observed difference in surface potential on the silver nano-plates were in good agreement. Our results show the possibility to sense the nano-crystal facets by appropriate choice of the substrate in ambient conditions.

Sensing the facet orientation in silver nano-plates using scanning Kelvin probe microscopy in air

International Nuclear Information System (INIS)

Abdellatif, M.H.; Salerno, M.; Polovitsyn, Anatolii; Marras, Sergio; De Angelis, Francesco

2017-01-01

Highlights: • The surface potential of drop cast nanocrystals was measured by SKPM in ambient air. • The nanocrystal facet work function was derived by theory. • By comparing theory and experiment we distinguished the nanocrystal facets. • Nanocrystal facet control is of practical interest for optoelectronic devices. - Abstract: The work function of nano-materials is important for a full characterization of their electronic properties. Because the band alignment, band bending and electronic noise are very sensitive to work function fluctuations, the dependence of the work function of nano-scale crystals on facet orientation can be a critical issue in optimizing optoelectronic devices based on these materials. We used scanning Kelvin probe microscopy to assess the local work function on samples of silver nano-plates at sub-micrometric spatial resolution. With the appropriate choice of the substrate and based on statistical analysis, it was possible to distinguish the surface potential of the different facets of silver nano-plates even if the measurements were done in ambient conditions without the use of vacuum. A phenomenological model was used to calculate the differences of facet work function of the silver nano-plates and the corresponding shift in Fermi level. This theoretical prediction and the experimentally observed difference in surface potential on the silver nano-plates were in good agreement. Our results show the possibility to sense the nano-crystal facets by appropriate choice of the substrate in ambient conditions.

High degree of genetic differentiation in marine three-spined sticklebacks (Gasterosteus aculeatus).

Science.gov (United States)

Defaveri, Jacquelin; Shikano, Takahito; Shimada, Yukinori; Merilä, Juha

2013-09-01

Populations of widespread marine organisms are typically characterized by a low degree of genetic differentiation in neutral genetic markers, but much less is known about differentiation in genes whose functional roles are associated with specific selection regimes. To uncover possible adaptive population divergence and heterogeneous genomic differentiation in marine three-spined sticklebacks (Gasterosteus aculeatus), we used a candidate gene-based genome-scan approach to analyse variability in 138 microsatellite loci located within/close to (<6 kb) functionally important genes in samples collected from ten geographic locations. The degree of genetic differentiation in markers classified as neutral or under balancing selection-as determined with several outlier detection methods-was low (F(ST) = 0.033 or 0.011, respectively), whereas average FST for directionally selected markers was significantly higher (F(ST) = 0.097). Clustering analyses provided support for genomic and geographic heterogeneity in selection: six genetic clusters were identified based on allele frequency differences in the directionally selected loci, whereas four were identified with the neutral loci. Allelic variation in several loci exhibited significant associations with environmental variables, supporting the conjecture that temperature and salinity, but not optic conditions, are important drivers of adaptive divergence among populations. In general, these results suggest that in spite of the high degree of physical connectivity and gene flow as inferred from neutral marker genes, marine stickleback populations are strongly genetically structured in loci associated with functionally relevant genes. © 2013 John Wiley & Sons Ltd.

Ten years after the Jali Commission

African Journals Online (AJOL)

Ten years have lapsed since the Jali Commission's final report became publicly available, and it is therefore an .... as the 'core business' of the department. This was seen as .... the 2009/10–2013/14 DCS Strategic Plan did the department ...

Early Predictors of Ten-Year Course in First-Episode Psychosis

DEFF Research Database (Denmark)

Friis, Svein; Melle, Ingrid; Johannessen, Jan Olav

2016-01-01

, five, and ten years (N=186 at ten years). Time in psychosis was defined as time with scores ≥4 on any of the Positive and Negative Syndrome Scale items P1, P3, P5, P6, and G9. Evaluations were retrospective, based on clinical interviews and all available clinical information. During the first two years......, patients were also evaluated by their clinicians at least biweekly. Baseline and early-course predictors of long-term course were identified with linear mixed-model analyses. RESULTS: Four variables provided significant, additive predictions of longer time in psychosis during the ten-year follow...

Ten years of nuclear power

Energy Technology Data Exchange (ETDEWEB)

NONE

1964-08-15

Ten years have elapsed since the world's first nuclear power station began to supply electricity in Russia, and this in turn marked the end of a twelve year stage following the first controlled nuclear chain reaction at Chicago. These periods mark major stages in the development of atomic energy from the realm of abstract ideas to that of everyday industrial application. They followed a period of fundamental research and laboratory work, culminating in Enrico Fermi's demonstration of a system whereby the forces of the atom could be brought under control. Then it was necessary to find ways and means of using the chain reaction for practical purposes and on an industrial scale. And after this had been shown in 1954 to be technically possible, it had still to be developed into an economic process. The nuclear power station has proved itself from the technical and engineering standpoint. The third phase of development has been to bring it to the stage of being economically competitive with alternative sources of energy, and it would appear that we are now reaching that goal - though more slowly than had been envisaged ten years ago

Von Blüten, Göttern und Gelehrten

OpenAIRE

Zotter, Astrid

2013-01-01

Der Sanskrittext Puṣpacintāmaṇi (PuCi) behandelt Blüten als Darbringungen (upacāra) im wichtigsten hinduistischen Verehrungsritual, der pūjā. In ca. 400 Strophen werden über 200 Namen von Blüten genannt und für verschiedene Gottheiten und pūjās als geeignete oder ungeeignete Gaben vorgeschrieben. Der Text ist eine Kompilation (Nibandha), in der die Inhalte aus 47 namentlich genannten Quellentexten referiert werden. Ziel der Dissertation ist es nicht nur, diesen Text, der 1966 zum ersten Ma...

Growth and structure of water on SiO2 films on Si investigated byKelvin probe microscopy and in situ X-ray Spectroscopies

Energy Technology Data Exchange (ETDEWEB)

Verdaguer, A.; Weis, C.; Oncins, G.; Ketteler, G.; Bluhm, H.; Salmeron, M.

2007-06-14

The growth of water on thin SiO{sub 2} films on Si wafers at vapor pressures between 1.5 and 4 torr and temperatures between -10 and 21 C has been studied in situ using Kelvin Probe Microscopy and X-ray photoemission and absorption spectroscopies. From 0 to 75% relative humidity (RH) water adsorbs forming a uniform film 4-5 layers thick. The surface potential increases in that RH range by about 400 mV and remains constant upon further increase of the RH. Above 75% RH the water film grows rapidly, reaching 6-7 monolayers at around 90% RH and forming a macroscopic drop near 100%. The O K-edge near-edge X-ray absorption spectrum around 75% RH is similar to that of liquid water (imperfect H-bonding coordination) at temperatures above 0 C and ice-like below 0 C.

Targeted/exome sequencing identified mutations in ten Chinese patients diagnosed with Noonan syndrome and related disorders

Directory of Open Access Journals (Sweden)

Shanshan Xu

2017-10-01

Full Text Available Abstract Background Noonan syndrome (NS and Noonan syndrome with multiple lentigines (NSML are autosomal dominant developmental disorders. NS and NSML are caused by abnormalities in genes that encode proteins related to the RAS-MAPK pathway, including PTPN11, RAF1, BRAF, and MAP2K. In this study, we diagnosed ten NS or NSML patients via targeted sequencing or whole exome sequencing (TS/WES. Methods TS/WES was performed to identify mutations in ten Chinese patients who exhibited the following manifestations: potential facial dysmorphisms, short stature, congenital heart defects, and developmental delay. Sanger sequencing was used to confirm the suspected pathological variants in the patients and their family members. Results TS/WES revealed three mutations in the PTPN11 gene, three mutations in RAF1 gene, and four mutations in BRAF gene in the NS and NSML patients who were previously diagnosed based on the abovementioned clinical features. All the identified mutations were determined to be de novo mutations. However, two patients who carried the same mutation in the RAF1 gene presented different clinical features. One patient with multiple lentigines was diagnosed with NSML, while the other patient without lentigines was diagnosed with NS. In addition, a patient who carried a hotspot mutation in the BRAF gene was diagnosed with NS instead of cardiofaciocutaneous syndrome (CFCS. Conclusions TS/WES has emerged as a useful tool for definitive diagnosis and accurate genetic counseling of atypical cases. In this study, we analyzed ten Chinese patients diagnosed with NS and related disorders and identified their correspondingPTPN11, RAF1, and BRAF mutations. Among the target genes, BRAF showed the same degree of correlation with NS incidence as that of PTPN11 or RAF1.

Assessing the effects of transcutaneous electrical nerve stimulation (TENS) in post-thoracotomy analgesia.

Science.gov (United States)

Ferreira, Fabiana Cristina; Issy, Adriana Machado; Sakata, Rioko Kimiko

2011-01-01

Transcutaneous electrical nerve stimulation (TENS) is commonly used to treat musculoskeletal pain, but it may also be indicated for postoperative analgesia. The objective of this study was to evaluate the analgesic effects of TENS on post-thoracotomy. Thirty patients between 18 and 60 years of age undergoing thoracotomy for lung cancer resection on the second postoperative day were included in this study. Patients were divided into two groups (G1 and G2). G1 patients were treated with TENS; and in G2 (without TENS) electrodes were placed but the equipment was not turned on. TENS was maintained for one hour. The visual analogue scale was used to evaluate the analgesic effects on three moments: before TENS (M0), immediately after TENS (M1), and one hour later (M2), with the patient at rest, elevation of the upper limbs, change in decubitus, and coughing. The intensity of pain at rest was higher in G2 immediately after TENS, but not one hour after the procedure. There was no difference between both groups with elevation of the upper limbs, decubitus change, and coughing. With the use of TENS for one hour on the second post-thoracotomy day in patients who received fentanyl (50 μg) associated with bupivacaine (5 mL), a reduction in pain intensity was observed at rest immediately after TENS; with elevation of the upper limbs, change in decubitus, and coughing, a reduction in pain severity was not observed. Copyright © 2011 Elsevier Editora Ltda. All rights reserved.

Kaluza-Klein supergravity in ten dimensions

International Nuclear Information System (INIS)

Huq, M.; Namazie, M.A.

1983-11-01

We construct a massive version of N=2 supergravity in ten dimensions by compactification of the eleven dimensional, N=1 theory. This theory describes the usual N=2 massless super-multiplet, in addition to which there is an infinite tower of massive, charged N=2 supermultiplets. (author)

Ten themes of viscous liquid dynamics

DEFF Research Database (Denmark)

Dyre, J. C.

2007-01-01

Ten ‘themes' of viscous liquid physics are discussed with a focus on how they point to a general description of equilibrium viscous liquid dynamics (i.e., fluctuations) at a given temperature. This description is based on standard time-dependent Ginzburg-Landau equations for the density fields...

Ten-year scheme of network development - 2013 edition

International Nuclear Information System (INIS)

2013-01-01

RTE, an independent subsidiary of EDF, is the French electricity transmission system operator. It is a public service company responsible for operating, maintaining and developing the high and extra high voltage network. It guarantees the reliability and proper operation of the power network. RTE transports electricity between electricity suppliers (French and European) and consumers, whether they are electricity distributors or industrial consumers directly connected to the transmission system. The mission of RTE is to balance the electricity supply and demand in real time. With the support of the government authorities, RTE prepares a ten-year scheme of network development in France; This document presents the main electricity transport infrastructures to foresee within the ten coming years and lists the network development investments which must be realised and implemented within 3 years. The document is updated each year and comes to complement at the national level the European ten year network development plan (TYNDP) and the European regional plans as provided for in the 2009/72/CE European directive

Transcutaneous electric nerve stimulation (TENS) for cancer pain in adults.

Science.gov (United States)

Hurlow, Adam; Bennett, Michael I; Robb, Karen A; Johnson, Mark I; Simpson, Karen H; Oxberry, Stephen G

2012-03-14

Cancer-related pain is complex and multi-dimensional but the mainstay of cancer pain management has predominantly used a biomedical approach. There is a need for non-pharmacological and innovative approaches. Transcutaneous Electric Nerve Stimulation (TENS) may have a role in pain management but the effectiveness of TENS is currently unknown. This is an update of the original review published in Issue 3, 2008. The aim of this systematic review was to determine the effectiveness of TENS for cancer-related pain in adults. The initial review searched The Cochrane Library, MEDLINE, EMBASE, CINAHL, PsychINFO, AMED and PEDRO databases in April 2008. We performed an updated search of CENTRAL, MEDLINE, EMBASE, CINAHL and PEDRO databases in November 2011. We included only randomised controlled trials (RCTS) investigating the use of TENS for the management of cancer-related pain in adults. The search strategy identified a further two studies for possible inclusion. One of the review authors screened each abstract using a study eligibility tool. Where eligibility could not be determined, a second author assessed the full paper. One author used a standardised data extraction sheet to collect information on the studies and independently assess the quality of the studies using the validated five-point Oxford Quality Scale. The small sample sizes and differences in patient study populations of the three included studies (two from the original review and a third included in this update) prevented meta-analysis. For the original review the search strategy identified 37 possible published studies; we divided these between two pairs of review authors who decided on study selection; all four review authors discussed and agreed final scores. Only one additional RCT met the eligibility criteria (24 participants) for this updated review. Although this was a feasibility study, not designed to investigate intervention effect, it suggested that TENS may improve bone pain on movement in a

Vadose Zone Journal: The first ten years

NARCIS (Netherlands)

Vrugt, J.A.; Or, D.; Young, M.H.

2013-01-01

Celebrating ten years of publication, the authors introduce a special section commemorating the anniversary of Vadose Zone Journal and reviewing the journal’s role in an evolving understanding of vadose zone science.

Dosimetry results for Big Ten and related benchmarks

International Nuclear Information System (INIS)

Hansen, G.E.; Gilliam, D.M.

1980-01-01

Measured average reaction cross sections for the Big Ten central flux spectrum are given together with calculated values based on the U.S. Evaluated Nuclear Data File ENDF/B-IV. Central reactivity coefficients for 233 U, 235 U, 239 Pu, 6 Li and 10 B are given to check consistency of bias between measured and calculated reaction cross sections for these isotopes. Spectral indexes for the Los Alamos 233 U, 235 U and 239 Pu metal critical assemblies are updated, utilizing the Big Ten measurements and interassembly calibrations, and their implications for inelastic scattering are reiterated

Immediate effects of tongue trills associated with transcutaneous electrical nerve stimulation (TENS).

Science.gov (United States)

Fabron, Eliana Maria Gradim; Petrini, Andressa Schweitzer; Cardoso, Vanessa de Moraes; Batista, João Carlos Torgal; Motonaga, Suely Mayumi; Marino, Viviane Cristina de Castro

2017-06-08

To investigate vocal quality variability after applying tongue trills associated with transcutaneous electrical nerve stimulation (TENS) on the larynx of women with normal laryngeal function. Additionally, to verify the effect of this technique over time on voice quality. Participants were 40 women (average 23.4 years) without vocal complaints. The procedure involved tongue trills with or without TENS for 3 minutes, rest and repeating the technique for another 2 minutes. The participants' voices were recorded before (Pre), after three minutes (Post 3min) and after two additional minutes (Post 5min) applying the technique. TENS with two electrodes was used on the thyroid cartilage. Self-assessment, acoustic and perceptual analysis were performed. When comparing tongue trills in isolation and associated with TENS, a greater sense of stability in phonation (self-assessment) and improvement in voice quality (perceptual evaluation) was observed in the combination technique. There was no statistical difference in acoustics findings between tongue trills in isolation and associated with TENS. When comparing the time effect of tongue trills with TENS in self-assessment there was a perception of less muscle tension (3min) and greater comfort during phonation (5 min); in the acoustic analysis, there was an increase of F0 (3 and 5 min) and intensity (5 min) when compared to Pre-moment; in the perceptual evaluation, better voice quality (3min). Comparing tongue trills in isolation and associated with TENS, there were changes in the comfort and muscle tension perception, as well as in vocal quality. On the other hand, tongue trills associated with TENS performed in 3 or 5 minutes resulted in beneficial effects on the voice identified in the assessments.

Feasibility study of Transcutaneous Electrical Nerve Stimulation (TENS) for cancer bone pain.

Science.gov (United States)

Bennett, Michael I; Johnson, Mark I; Brown, Sarah R; Radford, Helen; Brown, Julia M; Searle, Robert D

2010-04-01

This multicenter study assessed the feasibility of conducting a phase III trial of transcutaneous electrical nerve stimulation (TENS) in patients with cancer bone pain recruited from palliative care services. Eligible patients received active and placebo TENS for 1 hour at site of pain in a randomized crossover design; median interval between applications 3 days. Responses assessed at 30 and 60 minutes included numerical and verbal ratings of pain at rest and on movement, and pain relief. Recruitment, tolerability, adverse events, and effectiveness of blinding were also evaluated. Twenty-four patients were randomised and 19 completed both applications. The intervention was well tolerated. Five patients withdrew: 3 due to deteriorating performance status, and 2 due to increased pain (1 each following active and placebo TENS). Confidence interval estimation around the differences in outcomes between active and placebo TENS suggests that TENS has the potential to decrease pain on movement more than pain on rest. Nine patients did not consider that a placebo was used; the remaining 10 correctly identified placebo TENS. Feasibility studies are important in palliative care prior to undertaking clinical trials. Our findings suggest that further work is required on recruitment strategies and refining the control arm before evaluating TENS in cancer bone pain. Cancer bone pain is common and severe, and partly mediated by hyperexcitability. Animal studies suggest that Transcutaneous Electrical Nerve Stimulation can reduce hyperalgesia. This study examined the feasibility of evaluating TENS in patients with cancer bone pain in order to optimize methods before a phase III trial. Copyright 2010 American Pain Society. Published by Elsevier Inc. All rights reserved.

Verhalen sprokkelen langs de frontlijn. Een kritische blik op Ten Oorlog

Directory of Open Access Journals (Sweden)

Hans Boers

2015-03-01

Full Text Available Gathering Stories along the Front: A Critical Look at Ten Oorlog [To War]This article reflects critically on the popular television programme Ten Oorlog, thereby examining the field of tension between history and entertainment, between historians and ‘the public’. History can be addressed via various television formats as an historical documentary or a travel programme. An analysis indicates the extent to which Ten Oorlog is inspired by these formats. However, the popular television programme from the outset was not conceived as a classic historical documentary and perhaps can best be described as a historical human interest programme as part of the large-scale commemoration of the First World War. How do history and entertainment relate to one another in this programme? Is there more emphasis on the historical context or on anecdotal stories? This analysis of Ten Oorlog illustrates the tense relation between historians and ‘the public’.Dit artikel werpt een kritische blik op het populaire televisieprogramma Ten Oorlog en gaat daarbij in op het spanningsveld tussen geschiedenis en entertainment, tussen historici en ‘het publiek’. Geschiedenis kan via verschillende formats zoals een historische documentaire of een reisprogramma aan bod komen op televisie. Een analyse van deze formats geeft aan in welke mate Ten Oorlog hierop geïnspireerd is. Het populaire televisieprogramma was echter van begin af aan niet als een klassieke historische documentaire bedoeld en kan misschien het bestomschreven worden als een historisch human interest programma, in het kader van de grootschalige herdenking van de Eerste Wereldoorlog. Hoe verhoudengeschiedenis en entertainment zich daarin? Helt de balans meer over naar historische omkadering of naar anekdotische verhalen? Deze analyse van Ten Oorlog illustreert de gespannen relatie tussen historici en het grote publiek.

Scanning Kelvin probe force microscopy as a means of predicting the electrochemical characteristics of the surface of a modified AA4xxx/AA3xxx (Al alloys) brazing sheet

International Nuclear Information System (INIS)

Afshar, F. Norouzi; Wit, J.H.W. de; Terryn, H.; Mol, J.M.C.

2013-01-01

Highlights: ► Macro- and micro-electrochemical surface properties of an aluminium brazing sheet were investigated. ► Electrochemical surface properties before and after brazing were studied and compared. ► Scanning Kelvin probe force microscopy and potentiodynamic polarization measurements were performed. ► The electrochemical responses were correlated to the pre- and post-brazing treatment microstructure. -- Abstract: Macro- and micro-electrochemical properties of clad and core surfaces of a modified AA4xxx/AA3xxx brazing sheet material, before and after brazing, have been evaluated and compared. By scanning Kelvin probe force microscopy (SKPFM), the Volta potential distribution over the brazed and non-brazed clad surfaces was measured. The changes in the Volta potential maps were correlated to the macro-electrochemical responses of the surfaces and the microstructural features that evolve as a result of brazing. By performing potentiodynamic polarization experiments and microscopic analysis of the corroded surfaces and cross sections, the suitability of SKPFM analysis for corrosion performance prediction of the aluminium brazing sheet material in a sea water acidified accelerated test (SWAAT) environment was confirmed. Considering the purity of Si phase in the structures of both brazed and non-brazed material, it is suggested that Si can be applied as a reliable local reference in both structures to compare the changes in Volta potential differences as the result of different heat treatments of aluminium brazing sheet. Increasing the copper content of the re-solidified clad material as a result of brazing treatment was found to increase the Volta potential of the matrix which in turn reduces the cathodic protection power of the re-solidified clad material towards the core material

Distinguishing magnetic and electrostatic interactions by a Kelvin probe force microscopy–magnetic force microscopy combination

Directory of Open Access Journals (Sweden)

Miriam Jaafar

2011-09-01

Full Text Available The most outstanding feature of scanning force microscopy (SFM is its capability to detect various different short and long range interactions. In particular, magnetic force microscopy (MFM is used to characterize the domain configuration in ferromagnetic materials such as thin films grown by physical techniques or ferromagnetic nanostructures. It is a usual procedure to separate the topography and the magnetic signal by scanning at a lift distance of 25–50 nm such that the long range tip–sample interactions dominate. Nowadays, MFM is becoming a valuable technique to detect weak magnetic fields arising from low dimensional complex systems such as organic nanomagnets, superparamagnetic nanoparticles, carbon-based materials, etc. In all these cases, the magnetic nanocomponents and the substrate supporting them present quite different electronic behavior, i.e., they exhibit large surface potential differences causing heterogeneous electrostatic interaction between the tip and the sample that could be interpreted as a magnetic interaction. To distinguish clearly the origin of the tip–sample forces we propose to use a combination of Kelvin probe force microscopy (KPFM and MFM. The KPFM technique allows us to compensate in real time the electrostatic forces between the tip and the sample by minimizing the electrostatic contribution to the frequency shift signal. This is a great challenge in samples with low magnetic moment. In this work we studied an array of Co nanostructures that exhibit high electrostatic interaction with the MFM tip. Thanks to the use of the KPFM/MFM system we were able to separate the electric and magnetic interactions between the tip and the sample.

42 CFR 414.232 - Special payment rules for transcutaneous electrical nerve stimulators (TENS).

Science.gov (United States)

2010-10-01

... nerve stimulators (TENS). 414.232 Section 414.232 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES... Special payment rules for transcutaneous electrical nerve stimulators (TENS). (a) General payment rule. Except as provided in paragraph (b) of this section, payment for TENS is made on a purchase basis with...

Redundant Sensors for Mobile Robot Navigation

Science.gov (United States)

1985-09-01

represent a probability that the area is empty, while positive numbers mcan it’s probably occupied. Zero reprtsents the unknown. The basic idea is that...room to give it absolute positioning information. This works by using two infrared emitters and detectors on the robot. Measurements of anglcs are made...meters (T in Kelvin) 273 sec Distances returned when assuming 80 degrees Farenheit , but where. actual temperature is 60 degrees, will be seven inches

The use of positrons to study the shape of open-volume defects in cadmium as a function of temperature

International Nuclear Information System (INIS)

Selen, M.A.; Mackenzie, I.K.

1982-01-01

The properties of positrons and their use as solid state probes is discussed. The S and P parameters are defined. The concept of vacancies and pre-vacancies is introduced. Cadmium is shown to have highly anisotropic pre-vacancies which dominate positron trapping between 200 and 440 degrees Kelvin

Emission properties of Sm(III) complex having ten-coordination structure

International Nuclear Information System (INIS)

Hasegawa, Yasuchika; Tsuruoka, Shin-ichi; Yoshida, Takahiko; Kawai, Hideki; Kawai, Tsuyoshi

2008-01-01

Sammarium(III) complex having ten-coordination structure, bis-(1,10-phenanthroline)tris-(hexafluoroacetylacetonato)samarium(III) (Sm(hfa) 3 (phen) 2 ) was prepared by chelation of tris-(hexafluoroacetylacetonato) samarium(III) (Sm(hfa) 3 (H 2 O) 2 ) with 1,10-phenantroline (phen). The characteristic ten-coordination structure of Sm(hfa) 3 (phen) 2 was determined by 1 H NMR and elemental analyses. Strong deep-red emission (λ max =643 nm) and narrow emission band (FWHM=5 nm) of Sm(hfa) 3 (phen) 2 originated from electronic allowed transition from characteristics ten coordinate structure. The emission quantum yields Sm(hfa) 3 (phen) 2 excited at absorption bands of ligands and Sm(III) ion were found to be 0.36 and 1.4%, respectively

Comparison of two-stage thermophilic (68 degrees C/55 degrees C) anaerobic digestion with one-stage thermophilic (55 degrees C) digestion of cattle manure.

Science.gov (United States)

Nielsen, H B; Mladenovska, Z; Westermann, P; Ahring, B K

2004-05-05

A two-stage 68 degrees C/55 degrees C anaerobic degradation process for treatment of cattle manure was studied. In batch experiments, an increase of the specific methane yield, ranging from 24% to 56%, was obtained when cattle manure and its fractions (fibers and liquid) were pretreated at 68 degrees C for periods of 36, 108, and 168 h, and subsequently digested at 55 degrees C. In a lab-scale experiment, the performance of a two-stage reactor system, consisting of a digester operating at 68 degrees C with a hydraulic retention time (HRT) of 3 days, connected to a 55 degrees C reactor with 12-day HRT, was compared with a conventional single-stage reactor running at 55 degrees C with 15-days HRT. When an organic loading of 3 g volatile solids (VS) per liter per day was applied, the two-stage setup had a 6% to 8% higher specific methane yield and a 9% more effective VS-removal than the conventional single-stage reactor. The 68 degrees C reactor generated 7% to 9% of the total amount of methane of the two-stage system and maintained a volatile fatty acids (VFA) concentration of 4.0 to 4.4 g acetate per liter. Population size and activity of aceticlastic methanogens, syntrophic bacteria, and hydrolytic/fermentative bacteria were significantly lower in the 68 degrees C reactor than in the 55 degrees C reactors. The density levels of methanogens utilizing H2/CO2 or formate were, however, in the same range for all reactors, although the degradation of these substrates was significantly lower in the 68 degrees C reactor than in the 55 degrees C reactors. Temporal temperature gradient electrophoresis profiles (TTGE) of the 68 degrees C reactor demonstrated a stable bacterial community along with a less divergent community of archaeal species. Copyright 2004 Wiley Periodicals, Inc.

Ten per cent more grain

Energy Technology Data Exchange (ETDEWEB)

NONE

1967-08-15

At a low estimate, ten per cent of stored grain is lost every year to insect pests. In this article, based on a lecture given earlier this year in Switzerland, Dr. Harry E. Goresline, Food Radiation Specialist of the Food and Agriculture Organisation, now assisting the Joint FAO/IAEA Division of Atomic Energy in Food and Agriculture, explains how use of radiation can help to prevent losses and the research which has taken place to ensure its safety

Magnetic Anomalies over the Mid-Atlantic Ridge near 27{degrees}N.

Science.gov (United States)

Phillips, J D

1967-08-25

Ten magnetic profiles across the mid-Atlantic ridge near 27 degrees N show trends that are parallel to the ridge axis and symmetrical about the ridge axis. The configuration of magnetic bodies that could account for the pattern supports the Vine and Matthews hypothesis for the origin of magnetic anomalies over oceanic ridges. A polarity-reversal time scale inferred from models for sea-floor spreading in the Pacific-Antarctic ridge and radiometrically dated reversals of the geomagnetic field indicates a spreading rate of 1.25 centimeters per year during the last 6 million years and a rate of 1.65 centimeters per year between 6 and 10 million years ago. A similar analysis of more limited data over the mid-Atlantic ridge near 22 degrees N also indicates a change in the spreading rate. Here a rate of 1.4 centimeters per year appears to have been in effect during the last 5 million years; between 5 and 9 million years ago, an increased rate of 1.7 centimeters per year is indicated. The time of occurrence and relative magnitude of these changes in the spreading rate, about 5 to 6 million years ago and 18 to 27 percent, respectively, accords with the spreading rate change implied for the Juan de Fuca ridge in the northeast Pacific.

Transcutaneous Electrical Nerve Stimulation (TENS) reduces pain, fatigue, and hyperalgesia while restoring central inhibition in primary fibromyalgia

Science.gov (United States)

Dailey, Dana L; Rakel, Barbara A; Vance, Carol GT; Liebano, Richard E; Anand, Amrit S; Bush, Heather M; Lee, Kyoung S; Lee, Jennifer E; Sluka, Kathleen A

2014-01-01

Because TENS works by reducing central excitability and activating central inhibition pathways, we tested the hypothesis that TENS would reduce pain and fatigue and improve function and hyperalgesia in people with fibromyalgia who have enhanced central excitability and reduced inhibition. The current study used a double-blinded randomized, placebo controlled cross-over design to test effects of a single treatment of TENS in people with fibromyalgia. Three treatments were assessed in random order: active TENS, placebo TENS, no TENS. The following measures were assessed before and after each TENS treatment: pain and fatigue at rest and movement, pressure pain thresholds (PPTs), 6 minute walk test (6MWT), range of motion (ROM), five time sit to stand test (FTSTS), and single leg stance (SLS). Conditioned pain modulation (CPM) was completed at end of testing. There was a significant decrease in pain and fatigue with movement for active TENS compared to placebo and no TENS. PPTs increased at site of TENS (spine) and outside site of TENS (leg) when compared to placebo TENS or no TENS. During Active TENS CPM was significantly stronger compared to placebo TENS and no TENS. No changes in functional tasks were observed with TENS. Thus, the current study suggests TENS has short-term efficacy in relieving symptoms of fibromyalgia while the stimulator is active. Future clinical trials should examine the effects of repeated daily delivery of TENS, similar to how TENS is used clinically, on pain, fatigue, function and quality of life in individuals with fibromyalgia. PMID:23900134

Ten key issues in modern flow chemistry.

Science.gov (United States)

Wegner, Jens; Ceylan, Sascha; Kirschning, Andreas

2011-04-28

Ten essentials of synthesis in the flow mode, a new enabling technology in organic chemistry, are highlighted as flashlighted providing an insight into current and future issues and developments in this field. © The Royal Society of Chemistry 2011

Ten Leading Causes of Death and Injury

Science.gov (United States)

... Overdose Traumatic Brain Injury Violence Prevention Ten Leading Causes of Death and Injury Recommend on Facebook Tweet Share Compartir ... in Hospital Emergency Departments, United States – 2014 Leading Causes of Death Charts Causes of Death by Age Group 2016 [ ...

Age Group Comparisons of TENS Response Among Individuals With Chronic Axial Low Back Pain.

Science.gov (United States)

Simon, Corey B; Riley, Joseph L; Fillingim, Roger B; Bishop, Mark D; George, Steven Z

2015-12-01

Chronic low back pain (CLBP) is a highly prevalent and disabling musculoskeletal pain condition among older adults. Transcutaneous electrical nerve stimulation (TENS) is commonly used to treat CLBP, however response to TENS in older adults compared with younger adults is untested. In a dose-response study stratified by age, 60 participants with axial CLBP (20 young, 20 middle-aged, 20 older) received four 20-minute sessions of high-frequency high-intensity TENS over a 2- to 3-week period in a laboratory-controlled setting. Experimental measures of pain sensitivity (mechanical pressure pain detection threshold) and central pain excitability (phasic heat temporal summation and heat aftersensations) were assessed before and after TENS. Episodic or immediate axial CLBP relief was assessed after TENS via measures of resting pain, movement-evoked-pain, and self-reported disability. Cumulative or prolonged axial CLBP relief was assessed by comparing daily pain reports across sessions. Independent of age, individuals experienced episodic increase in the pressure pain detection threshold and reduction in aftersensation after TENS application. Similarly, all groups, on average, experienced episodic axial CLBP relief via improved resting pain, movement-evoked pain, and disability report. Under this design, no cumulative effect was observed as daily pain did not improve for any age group across the 4 sessions. However, older adults received higher TENS amplitude across all sessions to achieve TENS responses similar to those in younger adults. These findings suggest that older adults experience similar episodic axial CLBP relief to that of younger individuals after high-frequency, high-intensity TENS when higher dose parameters are used. This study examined age group differences in experimental and axial CLBP response to TENS, delivered under the current recommended parameters of strong, but tolerable amplitude. Older adults had comparable TENS response although at higher TENS

Why do different people choose different university degrees? Motivation and the choice of degree

Directory of Open Access Journals (Sweden)

Anya eSkatova

2014-11-01

Full Text Available Different people choose which undergraduate degree to study at the university for different reasons. To date, there have been limited attempts to identify individual differences in motivation that drive the undergraduate degree choice. We identified that people choose university degrees for four reasons: career concerns (Career, intrinsic interest (Interest in the subject, an opportunity to help others (Helping and because they are looking for an easy option into higher education (Loafing. We investigated whether these motivation apply to the choice of undergraduate degree in two samples: (1 undergraduate (N = 989 and (2 prospective (N = 896 students. We developed the Motivations Influencing Course Choice (MICC questionnaire to measure these motivations. Scales of Helping, Career, Loafing and Interest showed good psychometric properties, showed validity with respect to general life goals and personality traits, and predicted actual and prospective degree choices. We demonstrated that medical degrees were chosen due to a mixture of Helping and Career, while engineering degrees were associated with Career and low interest in the degree. The choice of art and humanities degrees was driven by Interest and low concern about future career, accompanied with high Loafing. We also demonstrated gender differences: females were high in Helping (both samples and Interest (only in undergraduate sample motivation, while males scored higher in Career (only in undergraduate sample and Loafing (both samples. The findings can feed into both theoretical accounts of proximal motivation as well as help to improve degree programmes at universities and provide better career advice.

Why do different people choose different university degrees? Motivation and the choice of degree.

Science.gov (United States)

Skatova, Anya; Ferguson, Eamonn

2014-01-01

Different people choose undergraduate degrees to study at university for different reasons. To date, there have been limited attempts to identify individual differences in motivation that drive undergraduate degree choice. We identified that people choose university degrees for four reasons: career concerns (Career), intrinsic interest in the subject (Interest), an opportunity to help others (Helping) and because they are looking for an easy option to get into higher education (Loafing). We investigated whether these motivations apply to the choice of undergraduate degree in two samples: (1) undergraduate (N = 989) and (2) prospective (N = 896) students. We developed the Motivations Influencing Course Choice (MICC) questionnaire to measure these motivations. Scales of Helping, Career, Loafing, and Interest showed good psychometric properties, showed validity with respect to general life goals and personality traits, and predicted actual and prospective degree choices. We demonstrated that medical degrees were chosen due to a mixture of Helping and Career, while engineering degrees were associated with Career and low Interest in the degree. The choice of arts and humanities degrees was driven by Interest and low concern about future career, accompanied with high Loafing. We also demonstrated gender differences: females were high in Helping (both samples) and Interest (only in the undergraduate sample) motivation, while males scored higher in Career (only in the undergraduate sample) and Loafing (both samples). The findings can feed into both theoretical accounts of proximal motivation as well as provide help to improve degree programmes at universities and support better career advice.

Comparative study of donor-induced quantum dots in Si nano-channels by single-electron transport characterization and Kelvin probe force microscopy

International Nuclear Information System (INIS)

Tyszka, K.; Moraru, D.; Samanta, A.; Mizuno, T.; Tabe, M.; Jabłoński, R.

2015-01-01

We comparatively study donor-induced quantum dots in Si nanoscale-channel transistors for a wide range of doping concentration by analysis of single-electron tunneling transport and surface potential measured by Kelvin probe force microscopy (KPFM). By correlating KPFM observations of donor-induced potential landscapes with simulations based on Thomas-Fermi approximation, it is demonstrated that single-electron tunneling transport at lowest gate voltages (for smallest coverage of screening electrons) is governed most frequently by only one dominant quantum dot, regardless of doping concentration. Doping concentration, however, primarily affects the internal structure of the quantum dot. At low concentrations, individual donors form most of the quantum dots, i.e., “donor-atom” quantum dots. In contrast, at high concentrations above metal-insulator transition, closely placed donors instead of individual donors form more complex quantum dots, i.e., “donor-cluster” quantum dots. The potential depth of these “donor-cluster” quantum dots is significantly reduced by increasing gate voltage (increasing coverage of screening electrons), leading to the occurrence of multiple competing quantum dots

Radiology now. The ten day rule - principles and practice

Energy Technology Data Exchange (ETDEWEB)

Carmichael, J H.E. [Broadgreen Hospital, Liverpool (UK); Warrick, C K

1978-11-01

The ten day rule recommends that non-urgent diagnostic radiography of the abdomen in women of child-bearing capacity should be confined to the pre-ovulatory phase of the menstrual cycle. Arguments for and against this rule are reviewed. The attitudes and organization of radiographic practice in the UK differ from those in the USA. Assessment of the evidence for the hazards involved leads to the conclusion that the continued application of the ten day rule should be strongly recommended as an essential part of good radiological and radiographic practice.

How green are the TEN-T core network corridors?

DEFF Research Database (Denmark)

Panagakos, George; Psaraftis, Harilaos N.

defining this concept, identified the characteristics that distinguish a green corridor from an otherwise efficient one. The main thesis of this paper is that the „core network corridors‟ of the new TEN-T guidelines exhibit all these qualities and the vision of a green corridor network in Europe is close...... to reality. To support this thesis, and in continuation of the work of SuperGreen, the paper examines the proposed new „guidelines‟ for the development of the TEN-T after presenting a brief history of transport network development in Europe....

Czech, Slovak science ten years after split

CERN Multimedia

2003-01-01

Ten years after the split of Czechoslovakia Czech and Slovak science are facing the same difficulties: shortage of money for research, poor salaries, obsolete equipment and brain drain, especially of the young, according to a feature in the Daily Lidove Noviny (1 page).

Importance of small-degree nodes in assortative networks with degree-weight correlations

Science.gov (United States)

Ma, Sijuan; Feng, Ling; Monterola, Christopher Pineda; Lai, Choy Heng

2017-10-01

It has been known that assortative network structure plays an important role in spreading dynamics for unweighted networks. Yet its influence on weighted networks is not clear, in particular when weight is strongly correlated with the degrees of the nodes as we empirically observed in Twitter. Here we use the self-consistent probability method and revised nonperturbative heterogenous mean-field theory method to investigate this influence on both susceptible-infective-recovered (SIR) and susceptible-infective-susceptible (SIS) spreading dynamics. Both our simulation and theoretical results show that while the critical threshold is not significantly influenced by the assortativity, the prevalence in the supercritical regime shows a crossover under different degree-weight correlations. In particular, unlike the case of random mixing networks, in assortative networks, the negative degree-weight correlation leads to higher prevalence in their spreading beyond the critical transmissivity than that of the positively correlated. In addition, the previously observed inhibition effect on spreading velocity by assortative structure is not apparent in negatively degree-weight correlated networks, while it is enhanced for that of the positively correlated. Detailed investigation into the degree distribution of the infected nodes reveals that small-degree nodes play essential roles in the supercritical phase of both SIR and SIS spreadings. Our results have direct implications in understanding viral information spreading over online social networks and epidemic spreading over contact networks.

Simultaneous determination of ten compounds in two main ...

African Journals Online (AJOL)

Simultaneous determination of ten compounds in two main medicinal plant parts of Tibetan herb, Pterocephalus hookeri (CB Clarke) Höeck, by ultra-high performance liquid chromatography-photodiode array.

Upscale Impact of Mesoscale Disturbances of Tropical Convection on Convectively Coupled Kelvin Waves

Science.gov (United States)

Yang, Q.; Majda, A.

2017-12-01

Tropical convection associated with convectively coupled Kelvin waves (CCKWs) is typically organized by an eastward-moving synoptic-scale convective envelope with numerous embedded westward-moving mesoscale disturbances. It is of central importance to assess upscale impact of mesoscale disturbances on CCKWs as mesoscale disturbances propagate at various tilt angles and speeds. Here a simple multi-scale model is used to capture this multi-scale structure, where mesoscale fluctuations are directly driven by mesoscale heating and synoptic-scale circulation is forced by mean heating and eddy transfer of momentum and temperature. The two-dimensional version of the multi-scale model drives the synoptic-scale circulation, successfully reproduces key features of flow fields with a front-to-rear tilt and compares well with results from a cloud resolving model. In the scenario with an elevated upright mean heating, the tilted vertical structure of synoptic-scale circulation is still induced by the upscale impact of mesoscale disturbances. In a faster propagation scenario, the upscale impact becomes less important, while the synoptic-scale circulation response to mean heating dominates. In the unrealistic scenario with upward/westward tilted mesoscale heating, positive potential temperature anomalies are induced in the leading edge, which will suppress shallow convection in a moist environment. In its three-dimensional version, results show that upscale impact of mesoscale disturbances that propagate at tilt angles (110o 250o) induces negative lower-tropospheric potential temperature anomalies in the leading edge, providing favorable conditions for shallow convection in a moist environment, while the remaining tilt angle cases have opposite effects. Even in the presence of upright mean heating, the front-to-rear tilted synoptic-scale circulation can still be induced by eddy terms at tilt angles (120o 240o). In the case with fast propagating mesoscale heating, positive

Top Ten Concerns for Trustees in 1988.

Science.gov (United States)

Meyerson, Joel W.

1988-01-01

Ten issues most likely to influence institutions this year include tuition policy and financing, capital renewal and replacement, charitable giving, scientific equipment and laboratories, endowment management and spending policy, research funding, corporate contributions, minority enrollment and hiring, debt financing and debt capacity, and cost…

Frictional amyloidosis in Oman - A study of ten cases

Directory of Open Access Journals (Sweden)

Mysore Venkataram

2002-01-01

Full Text Available Macular amyloidosis is an important cause for cutaneous pigmentation, the aetiology of which is poorly understood. Friction has recently been implicated the causation of early lesions, referred to as frictional amyloidosis. Confirmation of diagnosis by the detect on of amyloid using histochemical stains is inconsistent. Ten patients with pigmentation suggestive of macular amyloidosis were studied with detailed history, clinical examination, biopsy for histochemistry and electron microscopy. Nine out of ten patients had a history of prolonged friction with various objects such as bath sponges, brushes, towels, plant sticks and leaves. Amyloid was demonstrated by histochemical staining in only six out of ten cases. In the remaining four cases, amyloid was detected by electron microscopy. These consisted of aggregates of non-branching, extracellular, intertwining fibres measuring between 200-500 nm in length and between 20-25 nm in diameter. The study confirms the role of friction in the causation of this condition. Histochemical stains are not always successful in the detection of amyloid and electron microscopy is helpful for confirming its presence. The term frictional amyloidosis aptly describes the condition.

Dose-specific effects of transcutaneous electrical nerve stimulation (TENS) on experimental pain: a systematic review.

Science.gov (United States)

Claydon, Leica S; Chesterton, Linda S; Barlas, Panos; Sim, Julius

2011-09-01

To determine the hypoalgesic effects of transcutaneous electrical nerve stimulation (TENS) parameter combinations on experimental models in healthy humans. Searches were performed using the electronic databases Ovid MEDLINE, CINAHL, AMED, and Web of Science (from inception to December 2009). Manual searches of journals and reference lists of retrieved trials were also performed. Randomized controlled trials (RCTs) were included in the review if they compared the hypoalgesic effect of TENS relative with placebo and control, using an experimental pain model in healthy human participants. Two reviewers independently selected the trials, assessed their methodologic quality and extracted data. Forty-three RCTs were eligible for inclusion. A best evidence synthesis revealed: Overall "conflicting" (inconsistent findings in multiple RCTs) evidence of TENS efficacy on experimental pain irrespective of TENS parameters used. Overall intense TENS has "moderate" evidence of efficacy (1 high-quality and 2 low-quality trials). Conventional TENS has overall conflicting evidence of efficacy, this is derived from "strong" evidence of efficacy (generally consistent findings in multiple high-quality RCTs) on pressure pain but strong evidence of inefficacy on other pain models. "Limited" evidence (positive findings from 1 RCT) of hypoalgesia exists for some novel parameters. Low-intensity, low-frequency, local TENS has strong evidence of inefficacy. Inappropriate TENS (using "barely perceptible" intensities) has moderate evidence of inefficacy. The level of hypoalgesic efficacy of TENS is clearly dependent on TENS parameter combination selection (defined in terms of intensity, frequency, and stimulation site) and experimental pain model. Future clinical RCTs may consider these TENS dose responses.

[Smoking among psychology students over a ten-year period (1996-2006)].

Science.gov (United States)

Míguez Varela, María del Carmen; Becoña Iglesias, Elisardo

2009-11-01

The purpose of this study was to analyze the evolution of smoking among Psychology students at the University of Santiago de Compostela (Spain) over a ten-year period (1986-2006). We also assessed the extent of knowledge of the Spanish health legislation on tobacco (Ley 28/2005) and its effect on smoking. We administered a questionnaire to representative samples of students from the 1st year of their Psychology course to the 5th year, on four occasions. In the academic year 1996-1997 (N = 835), 34% of the sample claimed to be daily smokers; in 1999-2000 (N = 842), the figure was 35.2%; in 2003-2004 (N = 835) it was 31.9%; and in 2006-2007 (N = 688), it was 22.8%. Moreover, in the last assessment, 97.1% of the sample reported being aware of the legislation (Ley 28/2005) and 41.9% of the smokers claimed that it had some degree of influence on their smoking. It can be stated that, although overall current prevalence of smoking is similar to that of 10 years ago, a significant change is observed in the profile of smokers. This change is expressed in lower levels of nicotine dependence and a decrease in the percentage of daily smokers, together with an increase in occasional smokers.

Effect of SP-C on surface potential distribution in pulmonary surfactant: Atomic force microscopy and Kelvin probe force microscopy study

International Nuclear Information System (INIS)

Hane, Francis; Moores, Brad; Amrein, Matthias; Leonenko, Zoya

2009-01-01

The air-lung interface is covered by a molecular film of pulmonary surfactant (PS). The major function of the film is to reduce the surface tension of the lung's air-liquid interface, providing stability to the alveolar structure and reducing the work of breathing. Earlier we have shown that function of bovine lipid extract surfactant (BLES) is related to the specific molecular architecture of surfactant films. Defined molecular arrangement of the lipids and proteins of the surfactant film also give rise to a local highly variable electrical surface potential of the interface. In this work we investigated a simple model of artificial lung surfactant consisting of DPPC, eggPG, and surfactant protein C (SP-C). Effects of surface compression and the presence of SP-C on the monolayer structure and surface potential distribution were investigated using atomic force microscopy (AFM) and Kelvin probe force microscopy (KPFM). We show that topography and locally variable surface potential of DPPC-eggPG lipid mixture are similar to those of pulmonary surfactant BLES in the presence of SP-C and differ in surface potential when SP-C is absent.

Investigation of Kelvin-Helmholtz Instability in the boundary layer using Doppler lidar and radiosonde data

Science.gov (United States)

Das, Subrata Kumar; Das, Siddarth Shankar; Saha, Korak; Murali Krishna, U. V.; Dani, K. K.

2018-04-01

Characteristics of Kelvin Helmholtz Instability (KHI) using Doppler wind lidar observation have rarely been reported during the Indian summer monsoon season. In this paper, we present a case study of KHI near planetary boundary layer using Doppler wind lidar and radiosonde measurements at Mahabubnagar, a tropical Indian station. The data was collected during the Integrated Ground Observation Campaign (June-October 2011) under the Cloud Aerosol Interaction and Precipitation Enhancement EXperiment-2011. The continuous wind lidar observation during 10-16 August 2011 shows there is an increase in carrier-to-noise ratio values near planetary boundary layer from 03:00 to 11:00 LT on 13 August; reveals the formation of KHI. There is a strong power bursts pattern corresponding to high turbulence characteristics in the early half of the day. The KHI temporal evolution from initial to dissipating stage is observed with clear variation in the carrier-to-noise ratio values. The observed KHI billows are in the height between 600 and 1200 m and lasted for about 7.5 h. The vertical velocity from Doppler lidar measurement shows the presence of updrafts after breaking of KHI in the boundary layer. The presence of strong wind shear, high stability parameter, low Richardson number and high relative humidity during the enhanced carrier-to-noise ratio period indicates the ideal condition for the formation and persistence of this dynamic instability. A typical characteristic of trapped humidity above the KHI billows suggest the presence of strong inversion. A wavelet analysis of 3-dimensional wind components show dominant periodicity of 45-65 min and the periodicity in vertical wind is more prominent.

Anti-stress effects of transcutaneous electrical nerve stimulation (TENS) on colonic motility in rats.

Science.gov (United States)

Yoshimoto, Sazu; Babygirija, Reji; Dobner, Anthony; Ludwig, Kirk; Takahashi, Toku

2012-05-01

Disorders of colonic motility may contribute to symptoms in patients with irritable bowel syndrome (IBS), and stress is widely believed to play a major role in developing IBS. Stress increases corticotropin releasing factor (CRF) of the hypothalamus, resulting in acceleration of colonic transit in rodents. In contrast, hypothalamic oxytocin (OXT) has an anti-stress effect via inhibiting CRF expression and hypothalamic-pituitary-adrenal axis activity. Although transcutaneous electrical nerve stimulation (TENS) and acupuncture have been shown to have anti-stress effects, the mechanism of the beneficial effects remains unknown. We tested the hypothesis that TENS upregulates hypothalamic OXT expression resulting in reduced CRF expression and restoration of colonic dysmotility in response to chronic stress. Male SD rats received different types of stressors for seven consecutive days (chronic heterotypic stress). TENS was applied to the bilateral hind limbs every other day before stress loading. Another group of rats did not receive TENS treatment. TENS significantly attenuated accelerated colonic transit induced by chronic heterotypic stress, which was antagonized by a central injection of an OXT antagonist. Immunohistochemical study showed that TENS increased OXT expression and decreased CRF expression at the paraventricular nucleus (PVN) following chronic heterotypic stress. It is suggested that TENS upregulates hypothalamic OXT expression which acts as an anti-stressor agent and mediates restored colonic dysmotility following chronic stress. TENS may be useful to treat gastrointestinal symptoms associated with stress.

Efficacy of the use of two simultaneously TENS devices for fibromyalgia pain.

Science.gov (United States)

Lauretti, Gabriela Rocha; Chubaci, Eliana Fazuoli; Mattos, Anita Leocadia

2013-08-01

Fibromyalgia is characterized by a range of symptoms that include muscle pain, fatigue and sleep disorders. Transcutaneous electrical nerve stimulation (TENS) is an established method for pain relief. The purpose of the study was to evaluate the effectiveness and safety of the use of two simultaneously new TENS devices for fibromyalgia pain. After Ethics approval and informed consent, 39 patients were prospectively divided into three groups to evaluate TENS device, applied simultaneously in each patient: (1) at the lower back (perpendicular to the vertebrae canal, at the level of the 5th lumbar vertebrae) and (2) centrally above and below the space between the C7 and T1 spinous processes. The devices were applied for 20 min at 12-h interval during 7 consecutive days. For the placebo group (PG), the devices did not transmitted electrical stimulus. The single-TENS group (STG) (n = 13) had one active and one placebo TENS. The DTG applied both active TENS devices at the low back and cervical areas. Diclofenac was used as rescue analgesic. The efficacy measures were pain relief, reduction in use of daily analgesic tablets, quality of sleep and fatigue. The evaluation within groups revealed that patients from DPG refereed no pain relief when compared to their previous VAS pain score (8 cm, p > 0.05), while patients from the STG refereed improvement of 2.5 cm in the pain VAS (previous 8.5 cm compared to 6 cm after treatment) (p pain (previous 8.5-4.3 cm) (p STG > PG (p TENS improved pain relief in fibromyalgia pain, pain and fatigue were further improved when two active devices were simultaneously applied at the low back and cervical area, with no side effects.

Astrophysical parameters of ten poorly studied open star clusters

International Nuclear Information System (INIS)

Tadross, Ashraf Latif; El-Bendary, Reda; Osman, Anas; Ismail, Nader; Bakry, Abdel Aziz

2012-01-01

We present the fundamental parameters of ten open star clusters, nominated from Kronberger et al. who presented some newly discovered stellar groups on the basis of the Two Micron All Sky Survey photometry and Digitized Sky Survey visual images. Star counts and photometric parameters (radius, membership, distance, color excess, age, luminosity function, mass function, total mass, and dynamical relaxation time) have been determined for these ten clusters for the first time. In order to calibrate our procedures, the main parameters (distance, age, and color excess) have been re-estimated for another five clusters, which are also studied by Kronberger et al. (research papers)

Performance and microbial community composition dynamics of aerobic granular sludge from sequencing batch bubble column reactors operated at 20 degrees C, 30 degrees C, and 35 degrees C.

Science.gov (United States)

Ebrahimi, Sirous; Gabus, Sébastien; Rohrbach-Brandt, Emmanuelle; Hosseini, Maryam; Rossi, Pierre; Maillard, Julien; Holliger, Christof

2010-07-01

Two bubble column sequencing batch reactors fed with an artificial wastewater were operated at 20 degrees C, 30 degrees C, and 35 degrees C. In a first stage, stable granules were obtained at 20 degrees C, whereas fluffy structures were observed at 30 degrees C. Molecular analysis revealed high abundance of the operational taxonomic unit 208 (OTU 208) affiliating with filamentous bacteria Leptothrix spp. at 30 degrees C, an OTU much less abundant at 20 degrees C. The granular sludge obtained at 20 degrees C was used for the second stage during which one reactor was maintained at 20 degrees C and the second operated at 30 degrees C and 35 degrees C after prior gradual increase of temperature. Aerobic granular sludge with similar physical properties developed in both reactors but it had different nutrient elimination performances and microbial communities. At 20 degrees C, acetate was consumed during anaerobic feeding, and biological phosphorous removal was observed when Rhodocyclaceae-affiliating OTU 214 was present. At 30 degrees C and 35 degrees C, acetate was mainly consumed during aeration and phosphorous removal was insignificant. OTU 214 was almost absent but the Gammaproteobacteria-affiliating OTU 239 was more abundant than at 20 degrees C. Aerobic granular sludge at all temperatures contained abundantly the OTUs 224 and 289 affiliating with Sphingomonadaceae indicating that this bacterial family played an important role in maintaining stable granular structures.

Ten-Competence: Life-Long Competence Development and Learning

NARCIS (Netherlands)

Koper, Rob; Specht, Marcus

2006-01-01

Koper, R., & Specht, M. (2008). Ten-Competence: Life-Long Competence Development and Learning. In M-A. Cicilia (Ed.), Competencies in Organizational e-learning: concepts and tools (pp. 234-252). Hershey: IGI-Global.

Ten colour photometry of twelve Ap-stars

International Nuclear Information System (INIS)

Musielok, B.; Lange, D.; Schoeneich, W.; Hildebrandt, G.; Zelwanowa, E.; Hempelmann, A.; Salmanov, G.

1980-01-01

Ten-colour photoelectric observations are presented for twelve Ap-stars. Improved ephemeris for seven of them is given. Phase relations between the light curves and line intensity variations are discussed. The problem of the electromagnetic flux conctancy of IOTA Cas is approached from a qualitative point of view. (author)

Decay characteristics of electronic charged states of Si quantum dots as evaluated by an AFM/Kelvin probe technique

International Nuclear Information System (INIS)

Nishitani, Junichiro; Makihara, Katsunori; Ikeda, Mitsuhisa; Murakami, Hideki; Higashi, Seiichiro; Miyazaki, Seiichi

2006-01-01

Si quantum dots (Si-QDs) with an areal dot density of 8 x 10 11 cm -2 on SiO 2 have been prepared by the thermal decomposition of monosilane to characterize charged states of Si-QDs using AFM/Kelvin probe force microscopy (KFM). The temporal changes in the surface potential induced by electron charging and discharging at Si-QDs covered with a ∼ 2-nm-thick oxide layer have been measured. In electron charging and discharging at Si-QDs, a Rh-coated AFM tip was electrically biased in the range of - 5 to 5 V and scanned on the sample surface in a tapping mode. The surface potential changes on Si-QDs by electron injection and extraction were observable, while no potential change was detected elsewhere. The surface potential of charged Si-QDs decays with time at rates depending on charge injection conditions. The observed decay characteristics can be interpreted in terms of discharging of stored electrons in Si-QDs due to electron tunneling through the bottom oxide to the substrate and neutralization of stored holes due to recombination with electrons tunneling from the substrates. The defect generation in oxide is likely to be responsible for a fairly slow decay as observed in the case of electron extraction by the tip bias as high as + 4.8 V with respect to p-Si(100)

On coupled development of MHD instabilities of Rayleigh-Taylor and Kelvin-Helmholtz types in nonuniform gas-plasmas flows

International Nuclear Information System (INIS)

Likhachev, A P; Medin, S A

2010-01-01

The simultaneous development of the MHD instabilities of Raylegh-Taylor and Kelvin-Helmholtz types at the interface between high-conducting plasmoid and surrounding non- or low-conducting gas is considered. The linear stage of the RTI development is studied analytically for incompressible and compressible fluids. The nonlinear stage of the individual development of the RTI and the coupled development of both instabilities has been investigated numerically. The time-dependent two-dimensional numerical model based on the solution of the Euler gasdynamic equations with body momentum and energy sources of MHD origin has been developed and used in calculations. A disturbance introducing in the background flow has been periodic with varied assignment type and wave length. Fundamental difference between the results of linear and nonlinear analysis has been revealed. In particular, the increment of the RTI development at nonlinear stage is one-two order of magnitude less than that predicted by linear theory and rather weakly depends on initial disturbance mode. In linear analysis the coupled development of the RTI and the KHI is determined by simple summing of the two effects in the expression of wave increment, whereas in nonlinear case the mutual influence of the instabilities leads to essential alterations in their development, main of which is the intensive 'layer-by-layer' destruction of the plasmoid surface.

Transcutaneous electrical nerve stimulation (TENS) versus placebo for chronic low-back pain.

Science.gov (United States)

Khadilkar, Amole; Odebiyi, Daniel Oluwafemi; Brosseau, Lucie; Wells, George A

2008-10-08

Transcutaneous electrical nerve stimulation (TENS) was introduced more than 30 years ago as a therapeutic adjunct to the pharmacological management of pain. However, despite widespread use, its effectiveness in chronic low-back pain (LBP) is still controversial. To determine whether TENS is more effective than placebo for the management of chronic LBP. The Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, PEDro and CINAHL were searched up to July 19, 2007. Only randomized controlled clinical trials (RCTs) comparing TENS to placebo in patients with chronic LBP were included. Two review authors independently selected the trials, assessed their methodological quality and extracted relevant data. If quantitative meta-analysis was not possible, a qualitative synthesis was performed, taking into consideration 5 levels of evidence as recommended by the Cochrane Collaboration Back Review Group. Four high-quality RCTs (585 patients) met the selection criteria. Clinical heterogeneity prevented the use of meta-analysis. Therefore, a qualitative synthesis was completed. There was conflicting evidence about whether TENS was beneficial in reducing back pain intensity and consistent evidence in two trials (410 patients) that it did not improve back-specific functional status. There was moderate evidence that work status and the use of medical services did not change with treatment. Conflicting results were obtained from two studies regarding generic health status, with one study showing no improvement on the modified Sickness Impact Profile and another study showing significant improvements on several, but not all subsections of the SF-36 questionnaire. Multiple physical outcome measures lacked statistically significant improvement relative to placebo. In general, patients treated with acupuncture-like TENS responded similarly to those treated with conventional TENS. However, in two of the trials, an inadequate stimulation intensity was used for acupuncture

The application of the 'ten-day rule' in radiopharmaceutical investigations

International Nuclear Information System (INIS)

Ellis, R.E.; Nordin, B.E.C.; Tothill, P.; Veall, N.

1977-01-01

The working party first classified subjects who are investigated using radiopharmaceuticals into three groups, being (a) patients and other subjects who are asked to volunteer as controls for research studies, (b) patients on whom research investigations are being conducted which are relevant to their clinical condition but which are not strictly necessary for their management, and (c) patients on whom investigations are required for their proper management. The application of the 'ten-day rule' in relation to the use of radiopharmaceuticals is complicated by the fact that the total radiation dose is received over a time given by the effective life of the radiopharmaceutical in the organ, which may be a substantial part or even longer of the menstrual cycle. The activities of the radiopharmaceuticals normally administered are tabulted together with their effective half-lives and resulting gonad doses, and those radiopharmaceuticals requiring consideration of the implementation of the 'ten-day rule' for patients in groups (b) and (c) are identified. When the administration of therapeutic quantities of radiopharmaceuticals is being contemplated it is particularly important to take into account the applicability or otherwise of the 'ten-day rule'. It is recommended that the 'ten-day rule' should be strictly applied to all radiopharmaceutical administrations to women of child-bearing age who are volunteers for research purposes (group(a)). (U.K.)

Treatment of Idiopathic Chronic Orchialgia with Transcutaneous Electrical Nerve Stimulation (TENS:A Preliminary Result

Directory of Open Access Journals (Sweden)

Ekrem Akdeniz

2016-01-01

Full Text Available Purpose: Unilateral or bilateral testicular pain lasting more than 3 months is called as chronic orchialgia. Aproximately 25-50% of chronic orchialgia is idiopatic origin. This study aimed the effectiveness of Transcutaneous Electrical Nerve Stimulation (TENS therapy due to Idiopathic Chronic Orchialgia (ICO. Methods: Five patients were included into this study with ICO that diagnosed with physical examination, urine analyses, urinary system x-ray film, and scrotal doppler ultrasound. Medical history revealed that multiple conservative therapy attempts failed to alleviate the pain. Two of the patients had right sided ICO. Traditional TENS device is placed to the most painful points. TENS applied 3 times in a week with duration 30 minutes for 4 weeks. Before and after TENS application, patients were evaluated by using Visual Analog Scale (VAS at first and third months. Results: Median age of patients was 26.20±2.38 (22-30. Mean VAS value was 6.52 ± 0.89 before the procedure. After 1 month VAS value was 3.82 ± 0.83 (p0.05. None of the patients needed any analgesics after during the one month. No complications, hyperemia or hypoesthesia of the scrotal or penile skin, occurred after the procedure. Conclusion: TENS reduces pain by increasing endorphin release in the spinal cord dorsal horn. TENS is very effective method for first 1 month in patients with ICO but its effect reduces by the time. There is no standard therapeutic protocol for idiopathic chronic orchialgia. Therefore TENS may be an alternative for patients who do not benefit from medical therapy and do not want invasive procedures. Short-term use of TENS and low number of the patients are the limitations of this study. Randomized, placebo-controlled, and longer follow-up period studies are needed to better assess the efficacy of TENS for ICO.

Reactor dosimetry calibrations in the Big Ten critical assembly

International Nuclear Information System (INIS)

Barr, D.W.; Hansen, G.E.

1977-01-01

Eleven irradiations of foil packs located in the central region of Big Ten were made for the Interlaboratory Reaction Rate Program. Each irradiation was at a nominal 10 15 fluence and the principal fluence monitor was the National Bureau of Standards' double fission chamber containing 235 U and 238 U deposits and located at the center of Big Ten. Secondary monitors consisted of three external fission chambers and two internal foil sets containing Au, In, and Al. Activities of one set were counted at the LASL and the other at the Hanford Engineering Developement Laboratory. The uncertainty in relative fluence for each irradiation was +-0.3%

Transcutaneous electrical nerve stimulation (TENS) for pain control after vaginal delivery and cesarean section.

Science.gov (United States)

Kayman-Kose, Seda; Arioz, Dagistan Tolga; Toktas, Hasan; Koken, Gulengul; Kanat-Pektas, Mine; Kose, Mesut; Yilmazer, Mehmet

2014-10-01

The present study aims to determine the efficiency and reliability of transcutaneous electrical nerve stimulation (TENS) in the management of pain related with uterine contractions after vaginal delivery and the pain related with both abdominal incision uterine contractions after cesarean section. A hundred healthy women who underwent cesarean section under general anesthesia were randomly assigned to the placebo group (Group 1) or the TENS group (Group 2), while 100 women who delivered by vaginal route without episiotomy were randomized into the placebo group (Group 3) or the TENS group (Group 4). The patients in Group 2 had statistically lower visual analog scale (VAS) and verbal numerical scale (VNS) scores than the patients in Group 1 (p TENS (p = 0.006). The need for analgesics at the eighth hour of vaginal delivery was statistically similar in the patients who were treated with TENS and the patients who received placebo (p = 0.830). TENS is an effective, reliable, practical and easily available modality of treatment for postpartum pain.

Bitterness in sodium caseinate hydrolysates: role of enzyme preparation and degree of hydrolysis.

Science.gov (United States)

O'Sullivan, Dara; Nongonierma, Alice B; FitzGerald, Richard J

2017-10-01

Enzymatic hydrolysis of sodium caseinate (NaCas) may lead to the development of bitterness. Careful selection of hydrolysis conditions (i.e. enzyme preparation and duration) yielding different degrees of hydrolysis (DH) may aid in the development of low bitterness. Eighteen NaCas hydrolysates were generated with four enzyme preparations (Alcalase 2.4L, Prolyve 1000, FlavorPro Whey and pepsin) to different DH values. Hydrolysate bitterness score, assessed using a trained panel (ten assessors), generally increased at higher DH values for Alcalase, Prolyve and pepsin hydrolysates. However, all FlavorPro Whey hydrolysates (DH 0.38-10.62%) displayed low bitterness score values ( 0.05). Enzyme preparation and DH affect the bitterness of NaCas hydrolysates. The results are relevant for the generation of NaCas hydrolysates with reduced bitterness. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Giant multipole resonances: perspectives after ten years

International Nuclear Information System (INIS)

Bertrand, F.E.

1980-01-01

Nearly ten years ago evidence was published for the first of the so-called giant multipole resonances, the giant quadrupole resonance. During the ensuing years research in this field has spread to many nuclear physics laboratories throughout the world. The present status of electric giant multipole resonances is reviewed. 24 figures, 1 table

A controlled trial of transcutaneous electrical nerve stimulation (TENS) and exercise for chronic low back pain.

Science.gov (United States)

Deyo, R A; Walsh, N E; Martin, D C; Schoenfeld, L S; Ramamurthy, S

1990-06-07

A number of treatments are widely prescribed for chronic back pain, but few have been rigorously evaluated. We examined the effectiveness of transcutaneous electrical nerve stimulation (TENS), a program of stretching exercises, or a combination of both for low back pain. Patients with chronic low back pain (median duration, 4.1 years) were randomly assigned to receive daily treatment with TENS (n = 36), sham TENS (n = 36), TENS plus a program of exercises (n = 37), or sham TENS plus exercises (n = 36). After one month no clinically or statistically significant treatment effect of TENS was found on any of 11 indicators of outcome measuring pain, function, and back flexion; there was no interactive effect of TENS with exercise. Overall improvement in pain indicators was 47 percent with TENS and 42 percent with sham TENS (P not significant). The 95 percent confidence intervals for group differences excluded a major clinical benefit of TENS for most outcomes. By contrast, after one month patients in the exercise groups had significant improvement in self-rated pain scores, reduction in the frequency of pain, and greater levels of activity as compared with patients in the groups that did not exercise. The mean reported improvement in pain scores was 52 percent in the exercise groups and 37 percent in the nonexercise groups (P = 0.02). Two months after the active intervention, however, most patients had discontinued the exercises, and the initial improvements were gone. We conclude that for patients with chronic low back pain, treatment with TENS is no more effective than treatment with a placebo, and TENS adds no apparent benefit to that of exercise alone.

HRD Degrees.

Science.gov (United States)

Geber, Beverly

1987-01-01

The author describes the growing movement toward accreditation for human resources development professionals. She covers the issue of diversity, undergraduate versus graduate degrees, and future trends. (CH)

Ten Things Parents Can Do to Prevent Suicide

Science.gov (United States)

... Ribbon Commands Skip to main content Turn off Animations Turn on Animations Our Sponsors Log in | Register Menu Log in | ... teen at risk for suicide . Spend some time reading these ten ways you can help prevent a ...

Modification of the 'ten-day rule'

International Nuclear Information System (INIS)

Klempfner, G.

1985-01-01

In a 1964 decision the National Health and Medical Research Council recommended that radiological examinations of the lower abdomen and pelvis of women of childbearing age should be confined to the 10-day interval following the onset of menstruation. Recent evidence suggests that the first four weeks from the first day of the last menstrual period is not a critically radiosensitive period and consequently strict adherence to the ten-day rule is no longer indicated

HadISST (1-degree)/HadISST (1-degree)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Monthly version of HadISST sea surface temperature component (1-degree). See Rayner, N. A., Parker, D. E., Horton, E. B., Folland, C. K., Alexander, L. V., Rowell,...

Ten questions about systems biology

DEFF Research Database (Denmark)

Joyner, Michael J; Pedersen, Bente K

2011-01-01

to understand how whole animals adapt to the real world. We argue that a lack of fluency in these concepts is a major stumbling block for what has been narrowly defined as 'systems biology' by some of its leading advocates. We also point out that it is a failure of regulation at multiple levels that causes many......In this paper we raise 'ten questions' broadly related to 'omics', the term systems biology, and why the new biology has failed to deliver major therapeutic advances for many common diseases, especially diabetes and cardiovascular disease. We argue that a fundamentally narrow and reductionist...

Ten questions about systems biology

DEFF Research Database (Denmark)

Joyner, Michael J; Pedersen, Bente K

2011-01-01

In this paper we raise 'ten questions' broadly related to 'omics', the term systems biology, and why the new biology has failed to deliver major therapeutic advances for many common diseases, especially diabetes and cardiovascular disease. We argue that a fundamentally narrow and reductionist...... to understand how whole animals adapt to the real world. We argue that a lack of fluency in these concepts is a major stumbling block for what has been narrowly defined as 'systems biology' by some of its leading advocates. We also point out that it is a failure of regulation at multiple levels that causes many...

Set our Master's degrees free

Science.gov (United States)

Padman, Rachael

2010-04-01

Making UK undergraduate physics degrees longer must have seemed like a good idea at the time. Back in the early 1990s the standard three-year Bachelor's physics degree (four years in Scotland) was under pressure at both ends. The A-level curriculum - one of the requirements for entry onto a degree course - was being increasingly modularized, and dumbed down. Physics students were arriving at university less well prepared than in the past and there was an increasing awareness that graduates of five-year continental degree courses were better equipped for a professional scientific career than those in the UK. At the same time, local education authorities in the UK were required to provide full funding for a first degree, whether for three or four years.

Assessing composition and structure of soft biphasic media from Kelvin-Voigt fractional derivative model parameters

Science.gov (United States)

Zhang, Hongmei; Wang, Yue; Fatemi, Mostafa; Insana, Michael F.

2017-03-01

Kelvin-Voigt fractional derivative (KVFD) model parameters have been used to describe viscoelastic properties of soft tissues. However, translating model parameters into a concise set of intrinsic mechanical properties related to tissue composition and structure remains challenging. This paper begins by exploring these relationships using a biphasic emulsion materials with known composition. Mechanical properties are measured by analyzing data from two indentation techniques—ramp-stress relaxation and load-unload hysteresis tests. Material composition is predictably correlated with viscoelastic model parameters. Model parameters estimated from the tests reveal that elastic modulus E 0 closely approximates the shear modulus for pure gelatin. Fractional-order parameter α and time constant τ vary monotonically with the volume fraction of the material’s fluid component. α characterizes medium fluidity and the rate of energy dissipation, and τ is a viscous time constant. Numerical simulations suggest that the viscous coefficient η is proportional to the energy lost during quasi-static force-displacement cycles, E A . The slope of E A versus η is determined by α and the applied indentation ramp time T r. Experimental measurements from phantom and ex vivo liver data show close agreement with theoretical predictions of the η -{{E}A} relation. The relative error is less than 20% for emulsions 22% for liver. We find that KVFD model parameters form a concise features space for biphasic medium characterization that described time-varying mechanical properties. The experimental work was carried out at the Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA. Methodological development, including numerical simulation and all data analysis, were carried out at the school of Life Science and Technology, Xi’an JiaoTong University, 710049, China.

Elliot Lake uranium mine reclamation, the first ten years

International Nuclear Information System (INIS)

Payne, R.A.

2000-01-01

In 1989, Rio Algom Limited finalized its plans for the closure and subsequent decommissioning of two of its then three operating mines in Elliot Lake as a result of market conditions. These two mines closed in August 1990. These mine closures had significant impacts. The principal mining operations of Rio Algom at that time were still in Elliot Lake and had been the very foundation of the company for about 40 years. The business impact on the Corporation was regarded as possibly severe. The resultant layoff of over 1,500 long-term, highly qualified, skilled and well-paid employees, a devastating blow to the affected employees and their families, would have a significant financial impact on the municipal economy, particularly as this announcement was seen as the first step in the early closure of all four operating mines in the region. At that time there was little precedence for such a high profile mine closure program and consequently the many unknowns relating to the mine decommissioning process, legislative requirements and society's expectations resulted in a perception of a significant yet ill-defined liability. In this atmosphere of understandable company, stakeholder and public concern, Rio Algom Limited embarked on what has turned out to be a long, rigorous, challenging yet ultimately reasonable and rewarding process of progressive reclamation of all its Elliot Lake mines, some ten in total (nine uranium, one copper). Over the past ten years, reclamation of all ten mines has been successfully completed, some $70 m plus has been expended in direct site reclamation works and the workforce has been reduced from over 2,500 to just 4. After ten years, the focus of attention is now on the long-term care, maintenance, monitoring and reporting required for the decommissioned mine sites, and the accomplishment of this in the best interests of all the stakeholders. (author)

Field experiments on seed dispersal by wind in ten umbelliferous species (Apiaceae)

NARCIS (Netherlands)

Jongejans, E.; Telenius, A.

2001-01-01

This report presents data from experiments on seed dispersal by wind for ten species of the family Apiaceae. Seed shadows were obtained in the field under natural conditions, using wind speeds between four and ten m/s. The flight of individual seeds was followed by eye, and seed shadows were

Radiation therapy of penile cancer: six to ten-year follow-up

International Nuclear Information System (INIS)

Grabstald, H.; Kelley, C.D.

1980-01-01

Ten patients with penile cancer were treated with radiation therapy between 1968 and 1973. Nine of ten remain free of disease though in 1 patient a new penile primary developed eight years after the radiation therapy and was treated by partial penectomy. One patient died following surgery for ''bleeding ulcer.'' He was free of penile cancer five years after radiation. The most common complication is urethral stricture and skin telangiectasia

Novitäten im Breslauer Stadttheater

OpenAIRE

Zduniak, Maria

2017-01-01

Am Anfang des 20. Jahrhunderts zählte das Breslauer Stadttheater, obwohl mit nur einer kleinen Orchester-Besetzung ausgestattet, zu den bemerkenswerten europäischen Opernbühnen. Es war aufgeschlossen für musikalische Novitäten. Als Beweis dafür sind u.a. die Breslauer Premieren Salome (1906) von Richard Strauss, L\\'Orfeo (1913) von Claudio Monteverdi und die Uraufführung der Oper Eros und Psyche (1917) von Ludomir Różycki zu nennen.

Opposite Degree Algorithm and Its Applications

Directory of Open Access Journals (Sweden)

Xiao-Guang Yue

2015-12-01

Full Text Available The opposite (Opposite Degree, referred to as OD algorithm is an intelligent algorithm proposed by Yue Xiaoguang et al. Opposite degree algorithm is mainly based on the concept of opposite degree, combined with the idea of design of neural network and genetic algorithm and clustering analysis algorithm. The OD algorithm is divided into two sub algorithms, namely: opposite degree - numerical computation (OD-NC algorithm and opposite degree - Classification computation (OD-CC algorithm.

Ten-a affects the fusion of central complex primordia in Drosophila.

Directory of Open Access Journals (Sweden)

Xuebo Cheng

Full Text Available The central complex of Drosophila melanogaster plays important functions in various behaviors, such as visual and olfactory memory, visual orientation, sleep, and movement control. However little is known about the genes regulating the development of the central complex. Here we report that a mutant gene affecting central complex morphology, cbd (central brain defect, was mapped to ten-a, a type II trans-membrane protein coding gene. Down-regulation of ten-a in pan-neural cells contributed to abnormal morphology of central complex. Over-expression of ten-a by C767-Gal4 was able to partially restore the abnormal central complex morphology in the cbd mutant. Tracking the development of FB primordia revealed that C767-Gal4 labeled interhemispheric junction that separated fan-shaped body precursors at larval stage withdrew to allow the fusion of the precursors. While the C767-Gal4 labeled structure did not withdraw properly and detached from FB primordia, the two fan-shaped body precursors failed to fuse in the cbd mutant. We propose that the withdrawal of C767-Gal4 labeled structure is related to the formation of the fan-shaped body. Our result revealed the function of ten-a in central brain development, and possible cellular mechanism underlying Drosophila fan-shaped body formation.

On the relationship between degree of hand-preference and degree of language lateralization

NARCIS (Netherlands)

Somers, Metten; Ophoff, Roel A; Boks, Marco P; Fleer, Willemien; de Visser, Kees C L; Kahn, René S; Sommer, Iris E; Aukes, M.F.

2015-01-01

Language lateralization and hand-preference show inter-individual variation in the degree of lateralization to the left- or right, but their relation is not fully understood. Disentangling this relation could aid elucidating the mechanisms underlying these traits. The relation between degree of

Hydroxylated polybrominated diphenyl ethers exhibit different activities on thyroid hormone receptors depending on their degree of bromination.

Science.gov (United States)

Ren, Xiao-Min; Guo, Liang-Hong; Gao, Yu; Zhang, Bin-Tian; Wan, Bin

2013-05-01

Polybrominated diphenyl ethers (PBDEs) have been shown to disrupt thyroid hormone (TH) functions in experimental animals, and one of the proposed disruption mechanisms is direct binding of hydroxylated PBDE (OH-PBDE) to TH receptors (TRs). However, previous data on TH receptor binding and TH activity of OH-PBDEs were very limited and sometimes inconsistent. In the present paper, we examined the binding potency of ten OH-PBDEs with different degrees of bromination to TR using a fluorescence competitive binding assay. The results showed that the ten OH-PBDEs bound to TR with potency that correlated to their bromination level. We further examined their effect on TR using a coactivator binding assay and GH3 cell proliferation assay. Different TR activities of OH-PBDEs were observed depending on their degree of bromination. Four low-brominated OH-PBDEs (2'-OH-BDE-28, 3'-OH-BDE-28, 5-OH-BDE-47, 6-OH-BDE-47) were found to be TR agonists, which recruited the coactivator peptide and enhanced GH3 cell proliferation. However, three high-brominated OH-PBDEs (3-OH-BDE-100, 3'-OH-BDE-154, 4-OH-BDE-188) were tested to be antagonists. Molecular docking was employed to simulate the interactions of OH-PBDEs with TR and identify the structural determinants for TR binding and activity. According to the docking results, low-brominated OH-PBDEs, which are weak binders but TR agonists, bind with TR at the inner side of its binding pocket, whereas high-brominated compounds, which are potent binders but TR antagonists, reside at the outer region. These results indicate that OH-PBDEs have different activities on TR (agonistic or antagonistic), possibly due to their different binding geometries with the receptor. Copyright © 2013 Elsevier Inc. All rights reserved.

Reliability and validity of ten consumer activity trackers

NARCIS (Netherlands)

Kooiman, Thea; Dontje, Manon L.; Sprenger, Siska; Krijnen, Wim; van der Schans, Cees; de Groot, Martijn

2015-01-01

Background: Activity trackers can potentially stimulate users to increase their physical activity behavior. The aim of this study was to examine the reliability and validity of ten consumer activity trackers for measuring step count in both laboratory and free-living conditions. Method: Healthy

Diploma to degree 1976 to 1993

International Nuclear Information System (INIS)

Price, Richard

2009-01-01

The debate on degree education for radiographers began in earnest in the mid-1970s. Initially the debate hinged around whether a degree education was necessary for radiographers. One argument was that it was felt that a degree would separate academic and clinical training but eventually when degrees were introduced practical skills were assessed formally for the first time; something that had not been achieved with the Diploma of the College of Radiographers (DCR). The DCR itself became a barrier to degree education as the College of Radiographers (CoR) insisted that it was the only qualification recognised for state registration and as such would have to remain embedded as a distinct qualification within a degree. A major breakthrough came when the Council for National Academic Awards (CNAA) recognised the DCR at the same level as an ordinary degree. Around the same time the CoR published its Degree Rationale which announced a change in policy by not insisting that the DCR was sacrosanct. Developments followed rapidly and the first honours degree in radiography was validated in 1989 despite opposition from scientific officers at the Department of Health. Degrees were approved for state registration and radiography became a graduate profession by 1993 following years of debate and after overcoming opposition from both within and external to the profession.

Prominence Bubble Shear Flows and the Coupled Kelvin-Helmholtz — Rayleigh-Taylor Instability

Science.gov (United States)

Berger, Thomas; Hillier, Andrew

2017-08-01

Prominence bubbles are large arched structures that rise from below into quiescent prominences, often growing to heights on the order of 10 Mm before going unstable and generating plume upflows. While there is general agreement that emerging flux below pre-existing prominences causes the structures, there is lack of agreement on the nature of the bubbles and the cause of the instability flows. One hypothesis is that the bubbles contain coronal temperature plasma and rise into the prominence above due to both magnetic and thermal buoyancy, eventually breaking down via a magnetic Rayleigh-Taylor (RT) instability to release hot plasma and magnetic flux and helicity into the overlying coronal flux rope. Another posits that the bubbles are actually just “arcades” in the prominence indicating a magnetic separator line between the bipole and the prominence fields with the observed upflows and downflows caused by reconnection along the separator. We analyze Hinode/SOT, SDO/AIA, and IRIS observations of prominence bubbles, focusing on characteristics of the bubble boundary layers that may discriminate between the two hypotheses. We find speeds on the order of 10 km/s in prominence plasma downflows and lateral shear flows along the bubble boundary. Inflows to the boundary gradually increase the thickness and brightness of the layer until plasma drains from there, apparently around the dome-like bubble domain. In one case, shear flow across the bubble boundary develops Kelvin-Helmholtz (KH) vortices that we use to infer flow speeds in the low-density bubble on the order of 100 km/sec. IRIS spectra indicate that plasma flows on the bubble boundary at transition region temperatures achieve Doppler speeds on the order of 50 km/s, consistent with this inference. Combined magnetic KH-RT instability analysis leads to flux density estimates of 10 G with a field angle of 30° to the prominence, consistent with vector magnetic field measurements. In contrast, we find no evidence

Fracture toughness testing of V-4Cr-4Ti at 25{degrees}C and -196{degrees}C

Energy Technology Data Exchange (ETDEWEB)

Li, H.X.; Kurtz, R.J. [Pacific Northwest National Lab., Richland, WA (United States)

1996-10-01

Measurements of the fracture toughness of the production-scale heat (832665) of V-4Cr-4Ti have been performed at 25{degrees}C and {minus}196{degrees}C using compact tension (CT) specimens. Test specimens were vacuum annealed at either 1000{degrees}C for 1 hour (HT1) or 1050{degrees}C for two hours (HT2). Specimens given the HT1 treatment were annealed after final machining, whereas the HT2 specimens received the 1050{degrees}C anneal at Teledyne Wah Chang prior to final machining. Following machining HT2 specimens were then vacuum annealed at 180{degrees}C for two hours to remove hydrogen. Specimens treated using HT1 had a partially recrystallized microstructure and those treated using HT2 had a fully recrystallized microstructure. The fracture toughness at 25{degrees}C was determined by J-integral tests and at {minus}196{degrees}C by ASTM E 399 type tests. Toughness values obtained at {minus}196{degrees}C were converted to J-integral values for comparison to the 25{degrees}C data. The 25{degrees}C fracture toughness was very high with none of the specimens giving valid results per ASTM criteria. Specimens fractured by microvoid coalescence. The fracture toughness at {minus}196{degrees}C was much lower than that at 25{degrees}C and the fracture surface showed predominantly cleavage features. The present results show a transition from ductile to brittle behavior with decreasing test temperature which is not observed from one-third scale Charpy impact tests. The fracture toughness at {minus}196{degrees}C was still quite high, however, at about 75 kJ/m{sup 2}. Delaminations in planes normal to the thickness direction were seen at both test temperatures. Fracture surfaces inside the delaminations exhibited nearly 100% cleavage facets. The cause of the brittle delaminations was not determined, but will be a subject for further investigation.

The influence of transcutaneous electrical neurostimulation (TENS) on human cerebral blood flow velocities

NARCIS (Netherlands)

ter Laan, Mark; van Dijk, J. Marc C.; Elting, Jan-Willem J.; Fidler, Vaclav; Staal, Michiel J.

It has been shown that transcutaneous electrical neurostimulation (TENS) reduces sympathetic tone. Spinal cord stimulation (SCS) has proven qualities to improve coronary, peripheral, and cerebral blood circulation. Therefore, we postulate that TENS and SCS affect the autonomic nervous system in

Effects of transcutaneous electrical nerve stimulation (TENS) on cognition and behaviour in aging

NARCIS (Netherlands)

Scherder, E.J A; van Someren, E.W J; Bouma, J.M.; van der Berg, M

2000-01-01

In previous studies, transcutaneous electrical nerve stimulation (TENS) improved cognition and behaviour in patients with Alzheimer's disease (AD). The rationale underlying these studies was that TENS could activate, e.g. the septo-hippocampal region and the hypothalamus through direct and indirect

Effects of Transcutaneous Electrical Nerve Stimulation (TENS) on cognition and behaviour in aging

NARCIS (Netherlands)

Scherder, E.J.A.; Bouma, A.; van den Berg, M.

2000-01-01

In previous studies, transcutaneous electrical nerve stimulation (TENS) improved cognition and behaviour in patients with Alzheimer's disease (AD). The rationale underlying these studies was that TENS could activate, e.g. the septo-hippocampal region and the hypothalamus through direct and indirect

Ten Thousand Years of Solitude

Energy Technology Data Exchange (ETDEWEB)

Benford, G. (Los Alamos National Lab., NM (USA) California Univ., Irvine, CA (USA). Dept. of Physics); Kirkwood, C.W. (Los Alamos National Lab., NM (USA) Arizona State Univ., Tempe, AZ (USA). Coll. of Business Administration); Harry, O. (Los Alamos National Lab., NM (USA)); Pasqualetti, M.J. (Los Alamos National Lab., NM (USA) Arizona State Univ., Tempe, AZ (USA))

1991-03-01

This report documents the authors work as an expert team advising the US Department of Energy on modes of inadvertent intrusion over the next 10,000 years into the Waste Isolation Pilot Project (WIPP) nuclear waste repository. Credible types of potential future accidental intrusion into the WIPP are estimated as a basis for creating warning markers to prevent inadvertent intrusion. A six-step process is used to structure possible scenarios for such intrusion, and it is concluded that the probability of inadvertent intrusion into the WIPP repository over the next ten thousand years lies between one and twenty-five percent. 3 figs., 5 tabs.

Ten Thousand Years of Solitude?

International Nuclear Information System (INIS)

Benford, G.; Pasqualetti, M.J.

1991-03-01

This report documents the authors work as an expert team advising the US Department of Energy on modes of inadvertent intrusion over the next 10,000 years into the Waste Isolation Pilot Project (WIPP) nuclear waste repository. Credible types of potential future accidental intrusion into the WIPP are estimated as a basis for creating warning markers to prevent inadvertent intrusion. A six-step process is used to structure possible scenarios for such intrusion, and it is concluded that the probability of inadvertent intrusion into the WIPP repository over the next ten thousand years lies between one and twenty-five percent. 3 figs., 5 tabs

Ten questions on nuclear wastes

International Nuclear Information System (INIS)

Guillaumont, R.; Bacher, P.

2004-01-01

The authors give explanations and answers to ten issues related to nuclear wastes: when a radioactive material becomes a waste, how radioactive wastes are classified and particularly nuclear wastes in France, what are the risks associated with radioactive wastes, whether the present management of radioactive wastes is well controlled in France, which wastes are raising actual problems and what are the solutions, whether amounts and radio-toxicity of wastes can be reduced, whether all long life radionuclides or part of them can be transmuted, whether geologic storage of final wastes is inescapable, whether radioactive material can be warehoused over long durations, and how the information on radioactive waste management is organised

Comparison of two-stage thermophilic (68 degrees C/55 degrees C) anaerobic digestion with one-stage thermophilic (55 degrees C) digestion of cattle manure

DEFF Research Database (Denmark)

Nielsen, H.B.; Mladenovska, Zuzana; Westermann, Peter

2004-01-01

A two-stage 68degreesC/55degreesC anaerobic degradation process for treatment of cattle manure was studied. In batch experiments, an increase of the specific methane yield, ranging from 24% to 56%, was obtained when cattle manure and its fractions (fibers and liquid) were pretreated at 68degrees......, was compared with a conventional single-stage reactor running at 55degreesC with 15-days HRT. When an organic loading of 3 g volatile solids (VS) per liter per day was applied, the two-stage setup had a 6% to 8% higher specific methane yield and a 9% more effective VS-removal than the conventional single......-stage reactor. The 68degreesC reactor generated 7% to 9% of the total amount of methane of the two-stage system and maintained a volatile fatty acids (VFA) concentration of 4.0 to 4.4 g acetate per liter. Population size and activity of aceticlastic methanogens, syntrophic bacteria, and hydrolytic...

Ten recommendations for software engineering in research.

Science.gov (United States)

Hastings, Janna; Haug, Kenneth; Steinbeck, Christoph

2014-01-01

Research in the context of data-driven science requires a backbone of well-written software, but scientific researchers are typically not trained at length in software engineering, the principles for creating better software products. To address this gap, in particular for young researchers new to programming, we give ten recommendations to ensure the usability, sustainability and practicality of research software.

VINKA, ten years on. Main scientific results

International Nuclear Information System (INIS)

1979-01-01

The VINKA facility in the TRITON swimming-pool reactor at Fontenay-aux-Roses allows the irradiation of solids at low temperatures in order to study crystalline defects. After ten years of operation the main scientific results obtained in the fields of creep and growth (chapter I), point defects (chapter II), amorphisation (chapter III) and dechanneling of particles (chapter IV) are summarised [fr

Ten new withanolides from Physalis peruviana.

Science.gov (United States)

Fang, Sheng-Tao; Liu, Ji-Kai; Li, Bo

2012-01-01

Ten new withanolides, including four perulactone-type withanolides, perulactones E-H (1-4), three 28-hydroxy-withanolides, withaperuvins I-K (5-7), and three other withanolides, withaperuvins L-N (8-10), together with six known compounds (11-16) were isolated from the aerial parts of Physalis peruviana. The structures of these compounds were elucidated on the basis of extensive spectroscopic analyses (1D and 2D NMR, IR, HR-MS) and chemical methods. Copyright © 2011 Elsevier Inc. All rights reserved.

The Ten-Minute Neighbourhood Is [not] a Basic Planning Unit for Happiness in Egypt

Directory of Open Access Journals (Sweden)

Abeer Mohamed Elshater

2016-04-01

Full Text Available This paper investigates the relationship between inhabitants’ happiness and the right to the city in the status quo of Egyptian neighborhoods. Although services are easily accessible, by ten-minute walks in a suitable ambience, happiness is not achieved. The research aims to, first, review the literature that provides a guideline for ten-minute neighborhoods. Second, this study conducts a comparative content analysis of recent online articles on the right to the city. Third, the study tests findings from Egyptian neighborhood settings. The idea of a ten-minute neighborhood is manageable. The hypothesis concerns a compliant design. It is a logical assumption that people who live within ten minutes walking distance of essential facilities in their area can minimize several problems and maximize a healthy lifestyle. The supposed issue causes the right to the city to affect the relationship between ten-minute neighborhoods and citizens’ happiness. This assumption can be established through site observation and oriented questionnaires. This paper contributes by presenting new planning units that suit the current context of the old cities in the Middle East and North Africa region, based on walking distances of ten minutes or less with reference to the right to the city. This planning unit can result in citizens’ happiness.

A critical comparison of ten disposable cup LCAs

NARCIS (Netherlands)

Harst, van der E.J.M.; Potting, J.

2013-01-01

Disposable cups can be made from conventional petro-plastics, bioplastics, or paperboard (coated with petro-plastics or bioplastics). This study compared ten life cycle assessment (LCA) studies of disposable cups with the aim to evaluate the robustness of their results. The selected studies have

Maternity Nurses' Perceptions of Implementation of the Ten Steps to Successful Breastfeeding.

Science.gov (United States)

Cunningham, Emilie M; Doyle, Eva I; Bowden, Rodney G

The purpose of this study was to determine maternity nurses' perceptions of implementing the Ten Steps to Successful Breastfeeding. An online survey and a focus group were used to evaluate perceptions of maternity nurses of implementing the Ten Steps to Successful Breastfeeding in an urban Texas hospital at the onset of the project initiation. Responses were transcribed and coded using Nvivo software. Thematic analysis was conducted and consensus was reached among the research team to validate themes. Twenty-eight maternity nurses participated. Nurses perceived a number of barriers to implementing the Ten Steps to Successful Breastfeeding including nurse staffing shortages, variations in practice among nurses, different levels of nurse education and knowledge about breastfeeding, lack of parental awareness and knowledge about breastfeeding, culture, and postpartum issues such as maternal fatigue, visitors, and routine required procedures during recovery care that interfered with skin-to-skin positioning. Maternity nurses desired more education about breastfeeding; specifically, a hands-on approach, rather than formal classroom instruction, to be able to promote successful implementation of the Ten Steps. More education on breastfeeding for new mothers, their families, and healthcare providers was recommended. Nurse staffing should be adequate to support nurses in their efforts to promote breastfeeding. Skin-to-skin positioning should be integrated into the recovery period. Hospital leadership support for full implementation and policy adherence is essential. Challenges in implementing the Ten Steps were identified along with potential solutions.

Time in powers of ten natural phenomena and their timescales

CERN Document Server

't Hooft, Gerard

2014-01-01

In this richly illustrated book, Nobel Laureate Gerard 't Hooft and Theoretical Physicist Stefan Vandoren describe the enormous diversity of natural phenomena that take place at different time scales. In the tradition of the bestseller Powers of Ten , the authors zoom in and out in time, each step with a factor of ten. Starting from one second, time scales are enlarged until processes are reached that take much longer than the age of the universe. After the largest possible eternities, the reader is treated to the shortest and fastest phenomena known. Then the authors increase with powers of t

Ten-year statistics of the electric power supply. Status and tendencies

International Nuclear Information System (INIS)

2001-12-01

The ten-year statistics of the electric power supply in Denmark for 1991-2000 presents in tables and figures the trend of the electric power supply sector during the last ten years. The tables and figures present information on total energy consumption, combined heat and power generation, fuel consumption and the environment, the technical systems, economy and pricing, organization of the electricity supply, and information on electricity prices and taxes for households and industry in various countries. (LN)

Transcutaneous Electrical Nerve Stimulation (TENS) and Laryngeal Manual Therapy (LMT): Immediate Effects in Women With Dysphonia.

Science.gov (United States)

Conde, Mariana de Cásisa Macedo; Siqueira, Larissa Thaís Donalonso; Vendramini, José Eduardo; Brasolotto, Alcione Ghedini; Guirro, Rinaldo Roberto de Jesus; Silverio, Kelly Cristina Alves

2018-05-01

This study aimed to verify the immediate effect of low-frequency transcutaneous electrical nerve stimulation (TENS) and laryngeal manual therapy (LMT) in musculoskeletal pain, voice quality, and self-reported signs in women with dysphonia. Thirty women with behavioral dysphonia were randomly divided into the TENS group and the LMT group. All participants fulfilled the pain survey and had their voices recorded to posterior perceptual and acoustic analysis before and after intervention. The TENS group received a unique low-frequency TENS session (20 minutes). The LMT group received LMT (20 minutes) with soft and superficial massage in the sternocleidomastoid muscle, suprahyoid muscles, and larynx. Afterward, the volunteers reported their voice, larynx, breathing, and articulatory signs. Pre and post data were compared by parametric and nonparametric tests. After TENS, a decrease in pain intensity in the posterior or anterior region of the neck, shoulders, upper or lower back, and masseter was observed. After LMT, a decrease in pain intensity in the neck anterior region, shoulders, lower back, and temporal region was observed. Also, after TENS, there was an improvement in vowel /a/ instability; after LMT, there was a general improvement in voice quality, decrease in tension, and decrease in breathiness in speech. Positive voice and laryngeal signs were reported after TENS, and positive laryngeal signs and articulation were reported after LMT. TENS and LMT may be used in voice treatment of women with behavioral dysphonia, and both may be considered important therapy resources that reduce musculoskeletal pain and cause positive laryngeal signs. Both TENS and LMT are able to partially improve voice quality, but TENS presented better results. Copyright © 2018 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

Ten principles of good interdisciplinary team work.

Science.gov (United States)

Nancarrow, Susan A; Booth, Andrew; Ariss, Steven; Smith, Tony; Enderby, Pam; Roots, Alison

2013-05-10

Interdisciplinary team work is increasingly prevalent, supported by policies and practices that bring care closer to the patient and challenge traditional professional boundaries. To date, there has been a great deal of emphasis on the processes of team work, and in some cases, outcomes. This study draws on two sources of knowledge to identify the attributes of a good interdisciplinary team; a published systematic review of the literature on interdisciplinary team work, and the perceptions of over 253 staff from 11 community rehabilitation and intermediate care teams in the UK. These data sources were merged using qualitative content analysis to arrive at a framework that identifies characteristics and proposes ten competencies that support effective interdisciplinary team work. Ten characteristics underpinning effective interdisciplinary team work were identified: positive leadership and management attributes; communication strategies and structures; personal rewards, training and development; appropriate resources and procedures; appropriate skill mix; supportive team climate; individual characteristics that support interdisciplinary team work; clarity of vision; quality and outcomes of care; and respecting and understanding roles. We propose competency statements that an effective interdisciplinary team functioning at a high level should demonstrate.

The Kilo-Degree Survey

NARCIS (Netherlands)

de Jong, J. T. A.; Kuijken, K.; Applegate, D.; Begeman, K.; Belikov, A.; Blake, C.; Bout, J.; Boxhoorn, D.; Buddelmeijer, H.; Buddendiek, A.; Cacciato, M.; Capaccioli, M.; Choi, A.; Cordes, O.; Covone, G.; Dall'Ora, M.; Edge, A.; Erben, T.; Franse, J.; Getman, F.; Grado, A.; Harnois-Deraps, J.; Helmich, E.; Herbonnet, R.; Heymans, C.; Hildebrandt, H.; Hoekstra, H.; Huang, Z.; Irisarri, N.; Joachimi, B.; Köhlinger, F.; Kitching, T.; La Barbera, F.; Lacerda, P.; McFarland, J.; Miller, L.; Nakajima, R.; Napolitano, N. R.; Paolillo, M.; Peacock, J.; Pila-Diez, B.; Puddu, E.; Radovich, M.; Rifatto, A.; Schneider, P.; Schrabback, T.; Sifon, C.; Sikkema, G.; Simon, P.; Sutherland, W.; Tudorica, A.; Valentijn, E.; van der Burg, R.; van Uitert, E.; van Waerbeke, L.; Velander, M.; Kleijn, G. V.; Viola, M.; Vriend, W.-J.

2013-01-01

The Kilo-Degree Survey (KiDS), a 1500-square-degree optical imaging survey with the recently commissioned OmegaCAM wide-field imager on the VLT Survey Telescope (VST), is described. KiDS will image two fields in u-,g-,r- and i-bands and, together with the VIKING survey, produce nine-band (u- to

Age Group Comparisons of TENS Response among Individuals with Chronic Axial Low Back Pain

OpenAIRE

Simon, Corey B.; Riley, Joseph L.; Fillingim, Roger B.; Bishop, Mark D.; George, Steven Z.

2015-01-01

Chronic low back pain (CLBP) is a highly prevalent and disabling musculoskeletal pain condition among older adults. Transcutaneous electrical nerve stimulation (TENS) is commonly used to treat CLBP, however, TENS response for older adults compared to younger adults is untested. In a dose-response study stratified by age, sixty participants with axial CLBP (20 young, 20 middle-aged, 20 older) received four 20-minute sessions of high frequency, high intensity TENS over a two to three-week perio...

Ten-year statistics of the electric power supply. Status and tendencies

International Nuclear Information System (INIS)

2000-12-01

The ten-year statistics of the electric power supply in Denmark for 1990-1999 presents in tables and figures the trend of the electric power supply sector during the last ten years. The tables and figures present information on total energy consumption, combined heat and power generation, fuel consumption and the environment, the technical systems, economy and pricing, organization of the electricity supply, auto-production of electricity and information on electricity prices and taxes for households and industry in various countries. (LN)

The short-term effects of TENS plus therapeutic ultrasound combinations in chronic neck pain.

Science.gov (United States)

Sayilir, Selcuk

2018-05-01

To investigate the effects of TENS plus therapeutic ultrasound combinations on symptom relief, physical functionality, perceived stress levels, daytime sleepiness and neck mobility in patients with chronic neck pain (CNP). A total of 64 patients were divided into two groups as the TENS plus ultrasound group (n = 39) and the control CNP group (n = 25). The therapy comprised TENS and therapeutic ultrasound applications for 10 sessions. The control subjects were discouraged from using analgesics but were allowed to use paracetamol daily, if necessary. The Neck Disability Index (NDI), Epworth Sleepiness Scale (ESS), Perceived Stress Scale (PSS), visual analog scale (VAS) and tragus-wall/chin-manubrium distances were recorded at the baseline and after therapy. Significant improvements were detected in the TENS plus ultrasound group compared to the control CNP subjects in respect of VAS, PSS and NDI scores after the TENS plus therapeutic ultrasound therapies (all p stress levels and improving functionality in the short-term of CNP. Copyright © 2018 Elsevier Ltd. All rights reserved.

Ten questions about radiant heating and cooling systems

DEFF Research Database (Denmark)

Rhee, Kyu-Nam; Olesen, Bjarne W.; Kim, Kwang Woo

2017-01-01

to extend the applicability of the RHC system are providing the continuous impetus for research on RHC systems. This paper summarizes the important issues involved in the research on RHC system, whereby ten questions and answers concerning the RHC system are discussed, which will help researchers to conduct...

Defect-induced local variation of crystal phase transition temperature in metal-halide perovskites.

Science.gov (United States)

Dobrovolsky, Alexander; Merdasa, Aboma; Unger, Eva L; Yartsev, Arkady; Scheblykin, Ivan G

2017-06-26

Solution-processed organometal halide perovskites are hybrid crystalline semiconductors highly interesting for low-cost and efficient optoelectronics. Their properties are dependent on the crystal structure. Literature shows a variety of crystal phase transition temperatures and often a spread of the transition over tens of degrees Kelvin. We explain this inconsistency by demonstrating that the temperature of the tetragonal-to-orthorhombic phase transition in methylammonium lead triiodide depends on the concentration and nature of local defects. Phase transition in individual nanowires was studied by photoluminescence microspectroscopy and super-resolution imaging. We propose that upon cooling from 160 to 140 K, domains of the crystal containing fewer defects stay in the tetragonal phase longer than highly defected domains that readily transform to the high bandgap orthorhombic phase at higher temperatures. The existence of relatively pure tetragonal domains during the phase transition leads to drastic photoluminescence enhancement, which is inhomogeneously distributed across perovskite microcrystals.Understanding crystal phase transition in materials is of fundamental importance. Using luminescence spectroscopy and super-resolution imaging, Dobrovolsky et al. study the transition from the tetragonal to orthorhombic crystal phase in methylammonium lead triiodide nanowires at low temperature.

Research on pinch devices of tens of kA to MA

Energy Technology Data Exchange (ETDEWEB)

Soto, L.; Silva, P.; Moreno, J.; Silvester, G.; Zambra, M. [Comision Chilena de Energia Nuclear, Santiago (Chile); Pavez, C.; Saavedra, R. [Univ. de Concepcion (Chile); Bruzzone, H. [Pladema (Antiqua and Barbuda)]|[Univ. de Mar del Plata and CONICET (Argentina); Barbaglia, M. [Pladema (Antiqua and Barbuda); Mayer, R. [Pladema (Antiqua and Barbuda)]|[Inst. Balseiro, Bariloche, CNEA and CONICET (Argentina); Sidelnikov, Y.; Kies, W. [Heinrich-Heine-Univ., Duesseldorf (Germany)

2004-07-01

At present the Plasma Physics and Plasma Technology Group of the Comision Chilena de Energia Nuclear (CCHEN) has the experimental facilities in order to study dense transient discharges in a wide range of energy and current, namely: (I) energy from tens of joules to hundred of kilojoules, (II) current from tens of kiloamperes to some mega-amperes. Also several diagnostics have been implemented. An overview of the work being carried out on dense pinch discharges at the Comision Chilena de Energia Nuclear is presented. (orig.)

Research on pinch devices of tens of kA to MA

International Nuclear Information System (INIS)

Soto, L.; Silva, P.; Moreno, J.; Silvester, G.; Zambra, M.; Pavez, C.; Saavedra, R.; Bruzzone, H.; Barbaglia, M.; Mayer, R.; Sidelnikov, Y.; Kies, W.

2004-01-01

At present the Plasma Physics and Plasma Technology Group of the Comision Chilena de Energia Nuclear (CCHEN) has the experimental facilities in order to study dense transient discharges in a wide range of energy and current, namely: (I) energy from tens of joules to hundred of kilojoules, (II) current from tens of kiloamperes to some mega-amperes. Also several diagnostics have been implemented. An overview of the work being carried out on dense pinch discharges at the Comision Chilena de Energia Nuclear is presented. (orig.)

Antihypertensive effect of low-frequency transcutaneous electrical nerve stimulation (TENS) in comparison with drug treatment.

Science.gov (United States)

Silverdal, Jonas; Mourtzinis, Georgios; Stener-Victorin, Elisabet; Mannheimer, Clas; Manhem, Karin

2012-10-01

Hypertension is a major risk factor for vascular disease, yet blood pressure (BP) control is unsatisfactory low, partly due to side-effects. Transcutaneous electrical nerve stimulation (TENS) is well tolerated and studies have demonstrated BP reduction. In this study, we compared the BP lowering effect of 2.5 mg felodipin once daily with 30 min of bidaily low-frequency TENS in 32 adult hypertensive subjects (mean office BP 152.7/90.0 mmHg) in a randomized, crossover design. Office BP and 24-h ambulatory BP monitoring (ABPM) were performed at baseline and at the end of each 4-week treatment and washout period. Felodipin reduced office BP by 10/6 mmHg (p TENS reduced office BP by 5/1.5 mmHg (p TENS washout, BP was further reduced and significantly lower than at baseline, but at levels similar to BP after felodipin washout and therefore reasonably caused by factors other than the treatment per se. ABPM revealed a significant systolic reduction of 3 mmHg by felodipin, but no significant changes were noted after TENS. We conclude that our study does not present any solid evidence of BP reduction of TENS.

Optical spectroscopy of ten extragalactic radiosources

International Nuclear Information System (INIS)

Rawlings, S.; Riley, J.M.; Saunders, R.

1989-01-01

We present optical spectroscopy of ten objects associated with extra-galactic radiosources, using the University of Hawaii 2.2-m telescope. Redshifts are measured for four radiogalaxies (B20217 + 36A + B, 3C73, 0648 + 19A, 0648 + 19B) and for a galaxy which is probably associated with a double radio-source with highly unusual properties (0951 + 37); existing redshifts are confirmed for two radiogalaxies (4C39.04, 4C40.08); and a tentative redshift of z=2.87 measured for the quasar 3C82. (author)

A compact sub-Kelvin ultrahigh vacuum scanning tunneling microscope with high energy resolution and high stability.

Science.gov (United States)

Zhang, L; Miyamachi, T; Tomanić, T; Dehm, R; Wulfhekel, W

2011-10-01

We designed a scanning tunneling microscope working at sub-Kelvin temperatures in ultrahigh vacuum (UHV) in order to study the magnetic properties on the nanoscale. An entirely homebuilt three-stage cryostat is used to cool down the microscope head. The first stage is cooled with liquid nitrogen, the second stage with liquid (4)He. The third stage uses a closed-cycle Joule-Thomson refrigerator of a cooling power of 1 mW. A base temperature of 930 mK at the microscope head was achieved using expansion of (4)He, which can be reduced to ≈400 mK when using (3)He. The cryostat has a low liquid helium consumption of only 38 ml/h and standing times of up to 280 h. The fast cooling down of the samples (3 h) guarantees high sample throughput. Test experiments with a superconducting tip show a high energy resolution of 0.3 meV when performing scanning tunneling spectroscopy. The vertical stability of the tunnel junction is well below 1 pm (peak to peak) and the electric noise floor of tunneling current is about 6fA/√Hz. Atomic resolution with a tunneling current of 1 pA and 1 mV was achieved on Au(111). The lateral drift of the microscope at stable temperature is below 20 pm/h. A superconducting spilt-coil magnet allows to apply an out-of-plane magnetic field of up to 3 T at the sample surface. The flux vortices of a Nb(110) sample were clearly resolved in a map of differential conductance at 1.1 K and a magnetic field of 0.21 T. The setup is designed for in situ preparation of tip and samples under UHV condition.

School Psychologists' Job Satisfaction: Ten Years Later

OpenAIRE

Worrell, Travis G.

2004-01-01

School Psychologistsâ Job Satisfaction: Ten Years Later (ABSTRACT) This study was designed to replicate nationwide surveys completed in 1982 and 1992. The purpose was to examine and describe the levels of job satisfaction and the relationship between the variables in a national sample of school psychologists belonging to the National Association of School Psychologists (NASP). The sample for this study consisted of respondents who reported being full-time school practitioners. ...

Membrane status and in vitro capacitation of porcine sperm preserved in long-term extender at 16 degrees C.

Science.gov (United States)

Conejo-Nava, J; Fierro, R; Gutierrez, C G; Betancourt, M

2003-01-01

Preservation of porcine semen in long-term extenders at 15-18 degrees C for more than 5 days results in decreased farrowing rates and reduced litter size after artificial insemination, despite the high progressive motility rates of sperm. To improve this preservation system it is necessary to understand sperm physiology under storage conditions. The purpose of this study was to determine the effect of storing diluted porcine semen (during 0, 2, 4, 6, and 8 days) on the sperm membranes status and the ability of sperm to respond to in vitro capacitation treatment. Ten semen samples from 5 adult boars were analyzed. Two aliquots were obtained from the sperm-rich fraction: one was used to assess fresh semen and the other was diluted in Reading extender and stored at 16 degrees C. Both semen samples were stained with chlortetracycline to assess the status of sperm membranes and with Hoechst 33258 to determine viability. Semen storage for 4-8 days increased the proportion of prematurely capacitated sperm. After 4 days of storage, in vitro capacitation treatment did not increase the percentage of capacitated sperm, but increased the percentage of acrosome reacted sperm. This phenomenon could explain the reduced fertilizing ability of porcine semen stored at 16 degrees C for over 4 days, in spite of the acceptable sperm viability and progressive motility.

High-Latitude F-Region Irregularities: A Review and Synthesis

Science.gov (United States)

1988-02-15

8217% degree Farenheit tc (t r - f 459.67)/1.8 degree kelvin (K) -, electron volt 1.60219 xE -19 joule (J) k erg 1.000000 x E -7 jo,,le (J) :, erg/second...region altitudes [37, 38], but its absolute fluctuation intensity is much weaker than found near the peak of the F layer. Because walls of large-scale...N thought to occur only when the B component of the IMF is close to zero . %OX y ". Foster and Doupnik [129] showed that under disturbed conditions

Chemical Clarification Methods for Confined Dredged Material Disposal.

Science.gov (United States)

1983-07-01

foot second per metre cubic yards 0.7645549 cubic metres Farenheit degrees 5/9 Celsius degrees or Kelvins* feet 0.3048 metres feet per minute 0.3048...unknown in freshwater environments, use zero S.G. = specific gravity of solids; use 2.67 if unknown Wt. H20 [(weight of wet sample and dish, g...62.4 lb/ft v = average velocity, ft/sec Ps= absolute viscosity, 2.36 x 10-5 at 60F The duration t of the mixing is determined by t =L (6) v The net

Outcomes of torsional microcoaxial phacoemulsification performed by 12-degree and 22-degree bent tips.

Science.gov (United States)

Helvacioglu, Firat; Yeter, Celal; Tunc, Zeki; Sencan, Sadik

2013-08-01

To compare the safety and efficacy of Ozil Intelligent Phaco torsional microcoaxial phacoemulsification surgeries performed with 12-degree and 22-degree bent tips using the Infiniti Vision System. Maltepe University School of Medicine Department of Ophthalmology, Istanbul, Turkey. Comparative case series. Eyes were assigned to 2.2 mm microcoaxial phacoemulsification using the torsional mode with a 22-degree bent tip (Group 1) or a 12-degree bent tip (Group 2). The primary outcome measures were ultrasound time (UST), cumulative dissipated energy (CDE), longitudinal and torsional ultrasound (US) amplitudes, mean surgical time, mean volume of balanced salt solution used, and surgical complications. Both groups included 45 eyes. The mean UST, CDE, longitudinal US amplitude, and torsional US amplitude were 65 seconds ± 27.23 (SD), 11.53 ± 6.99, 0.22 ± 0.26, and 42.86 ± 15.64, respectively, in Group 1 and 84 ± 45.04 seconds, 16.68 ± 10.66, 0.48 ± 0.68, and 46.27 ± 14.74, respectively, in Group 2. The mean UST, CDE, and longitudinal amplitudes were significantly lower in Group 1 (P=.003, P=.008, and P=.022, respectively). The mean volume of balanced salt solution was 73.33 ± 28.58 cc in Group 1 and 82.08 ± 26.21 cc in Group 2 (P=.134). Torsional phacoemulsification performed with 22-degree bent tips provided more effective lens removal than 12-degree bent tips, with a lower UST and CDE. Copyright © 2013 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Fulfilling the atomic promise: Ten years history gives pointers for the future

International Nuclear Information System (INIS)

1967-01-01

Ten years is a short period in human history, and a short period in the life of an international organization. Nevertheless the ten years now completed by the International Atomic Energy Agency has seen much work accomplished and has brought greater realization than ever before of the promise held out by the atom for peaceful benefits leading to the promotion of peace, health and prosperity throughout the world

Breastfeeding Practices and Barriers to Implementing the Ten Steps to Successful Breastfeeding in Mississippi Hospitals.

Science.gov (United States)

Alakaam, Amir; Lemacks, Jennifer; Yadrick, Kathleen; Connell, Carol; Choi, Hwanseok Winston; Newman, Ray G

2018-05-01

Mississippi has the lowest rates of breastfeeding in the United States at 6 and 12 months. There is growing evidence that the rates and duration of infant breastfeeding improve after hospitals implement the Ten Steps to Successful Breastfeeding; moreover, the Ten Steps approach is considered the standard model for evaluation of breastfeeding practices in birthplaces. Research aim: This study aimed to examine the implementation level of the Ten Steps and identify barriers to implementing the Ten Steps in Mississippi hospitals. A cross-sectional self-report survey was used to answer the research aim. Nurse managers of the birthing and maternity units of all 43 Mississippi hospitals that provided birthing and maternity care were recruited. A response rate of 72% ( N = 31) was obtained. Implementation of the Ten Steps in these hospitals was categorized as low, partial, moderate, or high. The researcher classified implementation in 29% of hospitals as moderate and in 71% as partial. The hospital level of implementation was significantly positively associated with the hospital delivery rate along with the hospital cesarean section rate per year. The main barriers for the implementation process of the Ten Steps reported were resistance to new policies, limited financial and human resources, and lack of support from national and state governments. Breastfeeding practices in Mississippi hospitals need to be improved. New policies need to be established in Mississippi to encourage hospitals to adopt the Ten Steps policies and practice in the maternity and birthing units.

Families of Smooth Rational Curves of Small Degree on the Fano Variety of Degree 5 of Main Series

Directory of Open Access Journals (Sweden)

M. S. Omelkova

2013-01-01

Full Text Available In this paper we consider some families of smooth rational curves of degree 2, 3 and 4 on a smooth Fano threefold X which is a linear section of the Grassmanian G(1, 4 under the Pl¨ucker embedding. We prove that these families are irreducible. The proof of the irreducibility of the families of curves of degree d is based on the study of degeneration of a rational curve of degree d into a curve which decomposes into an irreducible rational curve of degree d−1 and a projective line intersecting transversally at a point. We prove that the Hilbert scheme of curves of degree d on X is smooth at the point corresponding to such a reducible curve. Then calculations in the framework of deformation theory show that such a curve varies into a smooth rational curve of degree d. Thus, the set of reducible curves of degree d of the above type lies in the closure of a unique component of the Hilbert scheme of smooth rational curves of degree d on X. From this fact and the irreducibility of the Hilbert scheme of smooth rational curves of degree d on the Grassmannian G(1, 4 one deduces the irreducibility of the Hilbert scheme of smooth rational curves of degree d on a general Fano threefold X.

45 CFR 2400.41 - Degree programs.

Science.gov (United States)

2010-10-01

... degree in history or political science (including government or politics), the degree of Master of Arts in Teaching in history or political science (including government or politics), or a related master's degree in education that permits a concentration in American history, American government, social studies...

LIGSITEcsc: predicting ligand binding sites using the Connolly surface and degree of conservation

Directory of Open Access Journals (Sweden)

Schroeder Michael

2006-09-01

Full Text Available Abstract Background Identifying pockets on protein surfaces is of great importance for many structure-based drug design applications and protein-ligand docking algorithms. Over the last ten years, many geometric methods for the prediction of ligand-binding sites have been developed. Results We present LIGSITEcsc, an extension and implementation of the LIGSITE algorithm. LIGSITEcsc is based on the notion of surface-solvent-surface events and the degree of conservation of the involved surface residues. We compare our algorithm to four other approaches, LIGSITE, CAST, PASS, and SURFNET, and evaluate all on a dataset of 48 unbound/bound structures and 210 bound-structures. LIGSITEcsc performs slightly better than the other tools and achieves a success rate of 71% and 75%, respectively. Conclusion The use of the Connolly surface leads to slight improvements, the prediction re-ranking by conservation to significant improvements of the binding site predictions. A web server for LIGSITEcsc and its source code is available at scoppi.biotec.tu-dresden.de/pocket.

Experiences and emotions of faculty teaching in accelerated second baccalaureate degree nursing programs.

Science.gov (United States)

Brandt, Cheryl L; Boellaard, Melissa R; Zorn, Cecelia R

2013-07-01

The number of accelerated second baccalaureate degree nursing (ASBSN) programs has mushroomed over recent decades, with more than 225 currently in existence. Scholars have described students and programs, but research examining the faculty experience is limited. The purpose of this study was to describe the experiences and emotions of faculty teaching students in ASBSN programs. Using a descriptive qualitative survey design, faculty (N = 138) from 25 randomly selected programs in 11 midwestern states were surveyed using an instrument developed for this study and distributed online. Ten themes emerged, including (a) Engaging With Motivated, Mature, and Diverse Students, (b) Students Choosing Nursing for the "Wrong Reasons," (c) Too Much Work, Too Little Time for Students and Faculty, (d) Amazement, (e) Pride, and (f) Frustration. These findings will help novice and seasoned ASBSN faculty interpret their experiences, strengthen precepting and mentoring activities, and support administrators in determining staffing plans and designing ASBSN programs. Copyright 2013, SLACK Incorporated.

Comparative study between manual therapy and TENS Burst in patients with tension-type cephalalgia

Directory of Open Access Journals (Sweden)

Denise Vasconcelos Fernandes

Full Text Available Introduction Cephalgia or cephalalgia is one of the most common symptoms in the general population. Objective To compare the efficacy of physical therapy modalities, through manual therapy and the effect of Transcutaneous Nerve Stimulation (TENS for tension-type cephalalgia. Materials and methods The study was compounded by 60 subjects, but only 40 of them completed it, due to the exclusion criteria. These were divided into control group and intervention group. The control group received treatment — manual therapy. The intervention group received TENS Burst. Patients underwent ten sessions of treatment, made at every two days on a week, lasting 30 minutes each session. Results The characteristics related to lifestyle, postural issues and range of motion are responsible for the main causes of tension-type cephalalgia. Discussion treatments showed effective results in all cases in relation to pain intensity, but the use of manual therapy techniques give the patient a better quality of life compared to the use of TENS. Final considerations The treatment of this condition deserves analysis and studies; however, there are only a few studying physical therapy techniques, especially regarding to the use of TENS.

Five-year results after valve replacement with the Björk-Shiley 70 degrees convexo-concave prosthesis.

Science.gov (United States)

Koldsland, S; Svennevig, J L; Abdelnoor, M; Aas, H; Semb, G

1992-01-01

In the 18 months up to July 1983, 120 Björk-Shiley convexo-concave prostheses with 70 degrees opening angle were implanted in 47 women and 61 men aged 19-78 (mean 58.6) years. The prosthetic valves were aortic in 65 cases, mitral in 23 and both aortic and mitral in 20 cases. Emergency operation was required in ten cases, and concomitant surgery was performed in 43 (39.8%). The early mortality was 5.5%. A follow-up study, comprising 498 patient years, revealed 73.1% 5-year survival. There were three mechanical failures of prosthesis, in one of which re-replacement was successful. Elective prosthesis replacement was performed in four other cases judged to be at high risk of strut fracture.

Self-esteem and depression: ten year follow-up of mothers and offspring.

Science.gov (United States)

Miller, L; Warner, V; Wickramaratne, P; Weissman, M

1999-01-01

The association between maternal bonding style, offspring low self-esteem and offspring depression status was assessed by maternal depression status. Sixty mothers and 137 offspring were independently assessed over the course of a ten year follow-up study. Assessments included the Schedule for Affective Disorders and Schizophrenia (SADS-LA), Schedule for Affective Disorders and Schizophrenia for School-Aged Children (K-SADS), the Coopersmith Self-Esteem Inventory (CSEI) and the Parental Bonding Instrument (PBI). Among daughters of mothers with a history of depression, maternal affectionless-control was associated with daughter low self-esteem which was associated with daughter depression at ten year follow-up. Among daughters of mothers without a history of depression, maternal affectionless-control was not associated with daughter low self-esteem, which was not associated with daughter depression at ten year follow-up but which was associated with a history of childhood depression. None of these associations were found to be significant among sons. As self-esteem was not measured at ten year follow-up, among offspring the stability of self-esteem could not be assessed, nor could the association between adult self-esteem and adult depression. Clinical presentation of low self-esteem in girls should be assessed in the context of maternal depression status.

Implementation fidelity of self-administered transcutaneous electrical nerve stimulation (TENS) in patients with chronic back pain: an observational study.

Science.gov (United States)

Pallett, Edward J; Rentowl, Patricia; Johnson, Mark I; Watson, Paul J

2014-03-01

The efficacy of transcutaneous electrical nerve stimulation (TENS) for pain relief has not been reliably established. Inconclusive findings could be due to inadequate TENS delivery and inappropriate outcome assessment. Electronic monitoring devices were used to determine patient compliance with a TENS intervention and outcome assessment protocol, to record pain scores before, during, and after TENS, and measure electrical output settings. Patients with chronic back pain consented to use TENS daily for 2 weeks and to report pain scores before, during, and after 1-hour treatments. A ≥ 30% reduction in pain scores was used to classify participants as TENS responders. Electronic monitoring devices "TLOG" and "TSCORE" recorded time and duration of TENS use, electrical settings, and pain scores. Forty-two patients consented to participate. One of 35 (3%) patients adhered completely to the TENS use and pain score reporting protocol. Fourteen of 33 (42%) were TENS responders according to electronic pain score data. Analgesia onset occurred within 30 to 60 minutes for 13/14 (93%) responders. It was not possible to correlate TENS amplitude, frequency, or pulse width measurements with therapeutic response. Findings from TENS research studies depend on the timing of outcome assessment; pain should be recorded during stimulation. TENS device sophistication might be an issue and parameter restriction should be considered. Careful protocol design is required to improve adherence and monitoring is necessary to evaluate the validity of findings. This observational study provides objective evidence to support concerns about poor implementation fidelity in TENS research.

Quantum golden field theory - Ten theorems and various conjectures

International Nuclear Information System (INIS)

El Naschie, M.S.

2008-01-01

Ten theorems and few conjectures related to quantum field theory as applied to high energy physics are presented. The work connects classical quantum field theory with the golden mean renormalization groups of non-linear dynamics and E-Infinity theory

[THE TEN MOST CITED ARTICLES OF THE JOURNAL "NUTRICION HOSPITALARIA"].

Science.gov (United States)

Franco-López, Ángeles; González-Gallego, Javier; Sanz-Valero, Javier; Tuñón, María Jesús; García-De-Lorenzo, Abelardo; Culebras, Jesús M

2015-12-01

After 36 years of continued publication of the journal Nutrición Hospitalaria, a list with the ten most cited articles published in it is elaborated. The top ten most cited articles in the world literature and stratification according to language, English or Spanish, subject, or period of time published are also analyzed. Nutr Hosp is the most important Ibero latin American nutrition journal. Nutr Hosp published 369 items in 2014 gaining the fourth position among all the world's journals devoted to nutrition. Article publication in English, or simultaneously in Spanish and English and Open Access policy probably benefit the number of citations. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Ten Indicators of Vitality in Smaller Academic Libraries

Science.gov (United States)

Pappas, David

2009-01-01

This paper provides a means of quickly ascertaining the relative health of smaller academic libraries by presenting a top ten list of vitality indicators. The list is based on an observational convenience sampling of thirty smaller academic libraries across the United States. The indicators making the list were those which appeared most often in…

Ten Strengths of How Teachers Do Cooperative Learning

Science.gov (United States)

Jaocbs, George M.

2016-01-01

Cooperative learning involves students in working together with peers to learn, to develop learning skills and to enjoy the learning process. This paper examines ten areas in which the author believes he and other teachers do cooperative learning well. These areas are: (1) keeping group size small, usually four or fewer; (2) encouraging students…

Unified SU(4) color models in ten dimensions

International Nuclear Information System (INIS)

Hanlon, B.E.; Joshi, G.C.

1992-01-01

Some aspects of constructing unified models with SU(4) as the color group via a unifying group defined in ten dimensions are examined. Four dimensional theories are recovered using the Coset Space Dimensional Reduction scheme. Candidate models are considered in order to highlight some of the difficulties in constructing realistic four dimensional theories. 30 refs

Virtual displays for 360-degree video

Science.gov (United States)

Gilbert, Stephen; Boonsuk, Wutthigrai; Kelly, Jonathan W.

2012-03-01

In this paper we describe a novel approach for comparing users' spatial cognition when using different depictions of 360- degree video on a traditional 2D display. By using virtual cameras within a game engine and texture mapping of these camera feeds to an arbitrary shape, we were able to offer users a 360-degree interface composed of four 90-degree views, two 180-degree views, or one 360-degree view of the same interactive environment. An example experiment is described using these interfaces. This technique for creating alternative displays of wide-angle video facilitates the exploration of how compressed or fish-eye distortions affect spatial perception of the environment and can benefit the creation of interfaces for surveillance and remote system teleoperation.

Simplification of the helical TEN2 laser

Science.gov (United States)

Krahn, K.-H.

1980-04-01

The observation that the helical TEN2 laser can effectively be simplified by giving up the use of decoupling elements as well as by abolishing the segmentation of the electrode structure is examined. Although, as a consequence of this simplification, the operating pressure range was slightly decreased, the output power could be improved by roughly 30%, a result which is attributed to the new electrode geometry exhibiting lower inductance and lower damping losses.

Antimicrobial activity of Verbascum macrurum Ten. (Scrophulariaceae).

Science.gov (United States)

Guarino, C

2002-01-01

The Author presents the results regarding the antibacterial action of extracts of Verbascum macrurum Ten.. The leaves of this species, gathered on the slopes of Mt. Matese, were ground and four extracts were made as follows: with dicholoromethane, ethonol and water (70:30 v/v), water and methanol. The antibacterial activity of each of the samples was tested and it is demonstrated that the extract with the ethanol/water was the most activity one.

[Comparison of the analgesic effect of interferential current (IFC) and TENS in patients with low back pain].

Science.gov (United States)

Grabiańska, Ewa; Leśniewicz, Joanna; Pieszyński, Ireneusz; Kostka, Joanna

2015-01-01

Electrotherapy, including theTENS and interferential current (IFC) is one of the most frequently used treatments in physical therapy in patients with low back pain. The aim of this study was to assess the influence of TENS and IFC on pain relief and to compare the analgesic efficacy of the two currents. Sixty patients aged 53.5 ± 12.5, with low back pain, were randomly divided into two groups: IFC (gr. I) and TENS (gr. II). Depending on the groups, patients were given series of ten 20-minute sessions using either IF orTENS currents. In all patients VAS and Laitinen modified scale were taken before and after treatment. After 2-weeks therapy there was improvement in the VAS and Laitinen scale (all components) in both groups, except for the part of the Laitinen scale on the reduction of activity in the group II (TENS). There was no statistically significant difference between the TENS and IF groups in reducing the intensity and other aspects of pain (frequency, pain medication and activity limitation) under the influence of therapy (p > 0.05). Interferential current and TENS therapy are effective for pain relief in patients with low back pain. The study showed equal analgesic efficacy of both treatments.

Measuring Direct Teaching Costs: Does an Undergraduate Business Degree Cost More to Produce than a Nonbusiness Degree?

Science.gov (United States)

Barth, Michael M.; Karagiannidis, Iordanis

2016-01-01

Many universities have implemented tuition differentials for certain undergraduate degree programs, citing higher degree costs or higher demand. However, most college accounting systems are unsuited for measuring cost differentials by degree program. This research outlines a method that can convert commonly available financial data to a more…

Labeling schemes for bounded degree graphs

DEFF Research Database (Denmark)

Adjiashvili, David; Rotbart, Noy Galil

2014-01-01

We investigate adjacency labeling schemes for graphs of bounded degree Δ = O(1). In particular, we present an optimal (up to an additive constant) log n + O(1) adjacency labeling scheme for bounded degree trees. The latter scheme is derived from a labeling scheme for bounded degree outerplanar...... graphs. Our results complement a similar bound recently obtained for bounded depth trees [Fraigniaud and Korman, SODA 2010], and may provide new insights for closing the long standing gap for adjacency in trees [Alstrup and Rauhe, FOCS 2002]. We also provide improved labeling schemes for bounded degree...

Ten steps to successful poster presentation.

Science.gov (United States)

Hardicre, Jayne; Devitt, Patric; Coad, Jane

Receiving a letter confirming acceptance for you to present a poster at a conference can evoke mixed emotions. Joy, panic, fear and dread are among the many possible emotions and this is not exclusive to first time presenters. Developing an effective poster presentation is a skill that you can learn and can provide a rewarding way to present your work in a manner less intimidating than oral presentation (Shelledy, 2004). The key to successful poster presentation is meticulous, timely, well informed preparation. This article outlines ten steps to help guide you through the process to maximize your success.

Audits reveal ten common environmental problems

International Nuclear Information System (INIS)

Buys, M.W.

1992-01-01

The old saying that open-quotes an ounce of prevention is worth a pound of cureclose quotes rings particularly true in environmental matters in the 1990s. Environmental problems can potentially lead to expensive fines, costly cleanups, negative public relations, and even criminal sanctions against members of the corporation. A recurring pattern of problems has been noted during the performance of environmental disposition, acquisition, and compliance assessments of many different operators in most of the producing states. The ten most common problems found in oilfield audits are discussed here in an effort to enhance the awareness of operators

Ten financial management principles for survival.

Science.gov (United States)

Cleverley, W O

1988-03-01

Financial insolvency is the primary cause of hospital failure. Managers may analyze a hospital's financial statements to anticipate and prevent fiscal problems. Ten measures of fiscal status may be used to evaluate the following: operating profitability nonoperating income equity growth liquidity debt capacity age of facilities revenue generation replacement funds receivables survivability Based on data from the Financial Analysis Service, Catholic hospitals are doing better than other U.S. hospitals in some areas of financial preparedness. In most areas, however, all hospitals suffer by comparison with manufacturers. The 10 principles of solvent and successful operations can help hospitals improve financial resiliency.

Lessons Learned: Creating an Online Business Degree from a Successful On-Campus Business Degree

Science.gov (United States)

Cordeiro, William P.; Muraoka, Dennis

2015-01-01

The horse has left the barn. Distance education is here to stay and the number of degree programs offered online is growing rapidly. California State University Channel Islands (CI) admitted its first students in 2002, and the undergraduate and graduate degrees in business were among its first program offerings. From its inception, the…

Cooling hyperthermic firefighters by immersing forearms and hands in 10 degrees C and 20 degrees C water.

Science.gov (United States)

Giesbrecht, Gordon G; Jamieson, Christopher; Cahill, Farrell

2007-06-01

Firefighters experience significant heat stress while working with heavy gear in a hot, humid environment. This study compared the cooling effectiveness of immersing the forearms and hands in 10 and 20 degrees C water. Six men (33 +/- 10 yr; 180 +/- 4 cm; 78 +/- 9 kg; 19 +/- 5% body fat) wore firefighter 'turn-out gear' (heavy clothing and breathing apparatus weighing 27 kg) in a protocol including three 20-min exercise bouts (step test, 78 W, 40 degrees C air, 40% RH) each followed by a 20-min rest/cooling (21 degrees C air); i.e., 60 min of exercise, 60 min of cooling. Turn-out gear was removed during rest/cooling periods and subjects either rested (Control), immersed their hands in 10 or 20 degrees C water (H-10, H-20), or immersed their hands and forearms in 10 or 20 degrees C water (HF-10, HF-20). In 20 degrees C water, hand immersion did not reduce core temperature compared with Control; however, including forearm immersion decreased core temperature below Control values after both the second and final exercise periods (p hand immersion produced a lower core temperature (0.8 degrees C above baseline) than all other conditions (1.1 to 1.4 degrees C above baseline) after the final exercise period (p Hand and forearm immersion in cool water is simple, reduces heat strain, and may increase work performance in a hot, humid environment. With 20 degrees C water, forearms should be immersed with the hands to be effective. At lower water temperatures, forearm and/or hand immersion will be effective, although forearm immersion will decrease core temperature further.

Transcutaneous electrical nerve stimulation (TENS) for phantom pain and stump pain following amputation in adults.

Science.gov (United States)

Johnson, Mark I; Mulvey, Matthew R; Bagnall, Anne-Marie

2015-08-18

This is the first update of a Cochrane review published in Issue 5, 2010 on transcutaneous electrical nerve stimulation (TENS) for phantom pain and stump pain following amputation in adults. Pain may present in a body part that has been amputated (phantom pain) or at the site of amputation (stump pain), or both. Phantom pain and stump pain are complex and multidimensional and the underlying pathophysiology remains unclear. The condition remains a severe burden for those who are affected by it. The mainstay treatments are predominately pharmacological, with increasing acknowledgement of the need for non-drug interventions. TENS has been recommended as a treatment option but there has been no systematic review of available evidence. Hence, the effectiveness of TENS for phantom pain and stump pain is currently unknown. To assess the analgesic effectiveness of TENS for the treatment of phantom pain and stump pain following amputation in adults. For the original version of the review we searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, PsycINFO, AMED, CINAHL, PEDRO and SPORTDiscus (February 2010). For this update, we searched the same databases for relevant randomised controlled trials (RCTs) from 2010 to 25 March 2015. We only included RCTs investigating the use of TENS for the management of phantom pain and stump pain following an amputation in adults. Two review authors independently assessed trial quality and extracted data. We planned that where available and appropriate, data from outcome measures were to be pooled and presented as an overall estimate of the effectiveness of TENS. In the original review there were no RCTs that examined the effectiveness of TENS for the treatment of phantom pain and stump pain in adults. For this update, we did not identify any additional RCTs for inclusion. There were no RCTs to judge the effectiveness of TENS for the management of phantom pain and stump pain. The published literature on TENS

Top Ten Challenges Facing the Next Secretary of Homeland Security

National Research Council Canada - National Science Library

2008-01-01

In an effort to assist with the first Presidential administration transition of the Department of Homeland Security, the Homeland Security Advisory Council has identified ten key challenges that will...

Socio-Demographic Determinants of Eclampsia in Calabar; A Ten ...

African Journals Online (AJOL)

A ten-year review of the socio-demographic determinants of eclampsia was ... had past histories of eclampsia, while in 7 (18.4%) cases history of change of ... no formal education and 34.25% were subsistence farmers living in the suburbs of ...

Transcutaneous electrical nerve stimulation (TENS) accelerates cutaneous wound healing and inhibits pro-inflammatory cytokines.

Science.gov (United States)

Gürgen, Seren Gülşen; Sayın, Oya; Cetin, Ferihan; Tuç Yücel, Ayşe

2014-06-01

The purpose of this study was to evaluate transcutaneous electrical nerve stimulation (TENS) and other common treatment methods used in the process of wound healing in terms of the expression levels of pro-inflammatory cytokines. In the study, 24 female and 24 male adult Wistar-Albino rats were divided into five groups: (1) the non-wounded group having no incision wounds, (2) the control group having incision wounds, (3) the TENS (2 Hz, 15 min) group, (4) the physiological saline (PS) group and (5) the povidone iodine (PI) group. In the skin sections, interleukin-1 beta (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) were assessed with enzyme-linked immunosorbent assay and immunohistochemical methods. In the non-wounded group, the expression of IL-1β, IL-6, and TNF-α signaling molecules was weaker in the whole tissue; however, in the control group, significant inflammatory response occurred, and strong cytokine expression was observed in the dermis, granulation tissue, hair follicles, and sebaceous glands (P TENS group, the decrease in TNF-α, IL-1β, and IL-6 immunoreaction in the skin was significant compared to the other forms of treatment (P TENS group suggest that TENS shortened the healing process by inhibating the inflammation phase.

Supersymmetric Yang-Mills theory on conformal supergravity backgrounds in ten dimensions

Energy Technology Data Exchange (ETDEWEB)

Medeiros, Paul de; Figueroa-O’Farrill, José [Maxwell Institute and School of Mathematics, The University of Edinburgh,James Clerk Maxwell Building, Peter Guthrie Tait Road, Edinburgh EH9 3FD (United Kingdom)

2016-03-14

We consider bosonic supersymmetric backgrounds of ten-dimensional conformal supergravity. Up to local conformal isometry, we classify the maximally supersymmetric backgrounds, determine their conformal symmetry superalgebras and show how they arise as near-horizon geometries of certain half-BPS backgrounds or as a plane-wave limit thereof. We then show how to define Yang-Mills theory with rigid supersymmetry on any supersymmetric conformal supergravity background and, in particular, on the maximally supersymmetric backgrounds. We conclude by commenting on a striking resemblance between the supersymmetric backgrounds of ten-dimensional conformal supergravity and those of eleven-dimensional Poincaré supergravity.

Ultra-cold molecule production

International Nuclear Information System (INIS)

Ramirez-Serrano, Jamie; Chandler, David W.; Strecker, Kevin; Rahn, Larry A.

2005-01-01

The production of Ultra-cold molecules is a goal of many laboratories through out the world. Here we are pursuing a unique technique that utilizes the kinematics of atomic and molecular collisions to achieve the goal of producing substantial numbers of sub Kelvin molecules confined in a trap. Here a trap is defined as an apparatus that spatially localizes, in a known location in the laboratory, a sample of molecules whose temperature is below one degree absolute Kelvin. Further, the storage time for the molecules must be sufficient to measure and possibly further cool the molecules. We utilize a technique unique to Sandia to form cold molecules from near mass degenerate collisions between atoms and molecules. This report describes the progress we have made using this novel technique and the further progress towards trapping molecules we have cooled

Stevens Johnson syndrome, toxic epidermal necrolysis and SJS-TEN overlap: A retrospective study of causative drugs and clinical outcome

Directory of Open Access Journals (Sweden)

Sharma Vinod

2008-01-01

Full Text Available Background and Aims: Stevens Johnson syndrome (SJS, toxic epidermal necrolysis (TEN and SJS-TEN overlap are serious adverse cutaneous drug reactions. Drugs are often implicated in these reactions. Methods: A retrospective analysis of inpatients′ data with these dermatological diagnoses were carried out for three years, to study the causative drugs, clinical outcome, and mortality in these conditions. Results: Thirty patients (15 TEN, nine SJS-TEN overlap, and six SJS were admitted. In 21 cases, multiple drugs were implicated whereas single drugs were responsible in nine. Anticonvulsants (35.08% were the most commonly implicated drugs followed by antibiotics (33.33% and NSAIDS (24.56%. Twenty-five patients recovered whereas five died (four TEN, one SJS-TEN overlap. Conclusion: Anticonvulsants, antibiotics and NSAIDs were the most frequently implicated drugs. TEN causes higher mortality than both SJS and SJS-TEN overlap.

An investigation into the effects of frequency-modulated transcutaneous electrical nerve stimulation (TENS) on experimentally-induced pressure pain in healthy human participants.

Science.gov (United States)

Chen, Chih-Chung; Johnson, Mark I

2009-10-01

Frequency-modulated transcutaneous electrical nerve stimulation (TENS) delivers currents that fluctuate between preset boundaries over a fixed period of time. This study compared the effects of constant-frequency TENS and frequency-modulated TENS on blunt pressure pain in healthy human volunteers. Thirty-six participants received constant-frequency TENS (80 pps), frequency-modulated TENS (20 to 100 pps), and placebo (no current) TENS at a strong nonpainful intensity in a randomized cross-over manner. Pain threshold was taken from the forearm using pressure algometry. There were no statistical differences between constant-frequency TENS and frequency-modulated TENS after 20 minutes (OR = 1.54; CI, 0.29, 8.23, P = 1.0). Both constant-frequency TENS and frequency-modulated TENS were superior to placebo TENS (OR = 59.5, P TENS does not influence hypoalgesia to any greater extent than constant-frequency TENS when currents generate a strong nonpainful paraesthesia at the site of pain. The finding that frequency-modulated TENS and constant-frequency TENS were superior to placebo TENS provides further evidence that a strong yet nonpainful TENS intensity is a prerequisite for hypoalgesia. This study provides evidence that TENS, delivered at a strong nonpainful intensity, increases pain threshold to pressure algometry in healthy participants over and above that seen with placebo (no current) TENS. Frequency-modulated TENS does not increase hypoalgesia to any appreciable extent to that seen with constant-frequency TENS.

Is there a role for TENS application in the control of diabetes mellitus in insulin-dependent patients?

Science.gov (United States)

Khan, Mueen Ullah

2012-11-01

An 80-year-old man with insulin-dependent diabetes mellitus presented to the hospital with low back pain. He was initially managed with non-steroidal anti-inflammatory drugs, tramadol and epidural steroid injection. Transcutaneous electrical nerve stimulation (TENS), applied on the back and buttocks, was subsequently advised. Initially, TENS was applied once every 24 hours. On improvement of pain symptoms, it was increased to thrice every 24 hours. The patient then complained of symptoms of hypoglycaemia (blood sugar level TENS resulted in raised blood sugar level. When TENS was restarted, the same hypoglycaemic response was noted. The insulin dosage was adjusted to half of the patient's routine daily requirement with continued application of TENS. This incidental finding has alerted us to hypoglycaemic episodes following TENS application, which may be due to effective pain control, decreased sympathetic stimulation, enhanced insulin sensitivity or altered muscle metabolism due to electrical stimulation.

A single trial of transcutaneous electrical nerve stimulation (TENS) improves spasticity and balance in patients with chronic stroke.

Science.gov (United States)

Cho, Hwi-young; In, Tae Sung; Cho, Ki Hun; Song, Chang Ho

2013-03-01

Spasticity management is pivotal for achieving functional recovery of stroke patients. The purpose of this study was to investigate the effects of a single trial of transcutaneous electrical nerve stimulation (TENS) on spasticity and balance in chronic stroke patients. Forty-two chronic stroke patients were randomly allocated into the TENS (n = 22) or the placebo-TENS (n = 20) group. TENS stimulation was applied to the gastrocnemius for 60 min at 100 Hz, 200 µs with 2 to 3 times the sensory threshold (the minimal threshold in detecting electrical stimulation for subjects) after received physical therapy for 30 min. In the placebo-TENS group, electrodes were placed but no electrical stimulation was administered. For measuring spasticity, the resistance encountered during passive muscle stretching of ankle joint was assessed using the Modified Ashworth Scale, and the Hand held dynamometer was used to assess the resistive force caused by spasticity. Balance ability was measured using a force platform that measures postural sway generated by postural imbalance. The TENS group showed a significantly greater reduction in spasticity of the gastrocnemius, compared to the placebo-TENS group (p TENS resulted in greater balance ability improvements, especially during the eyes closed condition (p TENS provides an immediately effective means of reducing spasticity and of improving balance in chronic stroke patients. The present data may be useful to establish the standard parameters for TENS application in the clinical setting of stroke.

Electron collisions with Fe-peak elements: Forbidden transitions between the low lying valence states 3d6, 3d54s, and 3d54p of Fe III

International Nuclear Information System (INIS)

McLaughlin, B.M.; Scott, M.P.; Sunderland, A.G.; Noble, C.J.; Burke, V.M.; Ramsbottom, C.A.; Reid, R.H.G.; Hibbert, A.; Bell, K.L.; Burke, P.G.

2007-01-01

Effective collision strengths are presented for the Fe-peak element Fe III at electron temperatures (T e in degrees Kelvin) in the range 2 x 10 3 to 1 x 10 6 . Forbidden transitions results are given between the 3d 6 , 3d 5 4s, and the 3d 5 4p manifolds applicable to the modeling of laboratory and astrophysical plasmas

The Big Chill

CERN Multimedia

2001-01-01

In just five years the LHC's twenty-seven kilometre ring of superconducting magnets will be brought down to a chily 1.9 Kelvin - some 300 degrees below room temperature - as CERN's new flagship accelerator is commissioned. Validating all the systems that will cool and power the LHC is the job of String 2, a chain of prototype magnets currently being put through its paces in SM18.

Performance Analysis of Ten Common QRS Detectors on Different ECG Application Cases

Directory of Open Access Journals (Sweden)

Feifei Liu

2018-01-01

Full Text Available A systematical evaluation work was performed on ten widely used and high-efficient QRS detection algorithms in this study, aiming at verifying their performances and usefulness in different application situations. Four experiments were carried on six internationally recognized databases. Firstly, in the test of high-quality ECG database versus low-quality ECG database, for high signal quality database, all ten QRS detection algorithms had very high detection accuracy (F1 >99%, whereas the F1 results decrease significantly for the poor signal-quality ECG signals (all 95% except RS slope algorithm with 94.24% on normal ECG database and 94.44% on arrhythmia database. Thirdly, for the paced rhythm ECG database, all ten algorithms were immune to the paced beats (>94% except the RS slope method, which only output a low F1 result of 78.99%. At last, the detection accuracies had obvious decreases when dealing with the dynamic telehealth ECG signals (all <80% except OKB algorithm with 80.43%. Furthermore, the time costs from analyzing a 10 s ECG segment were given as the quantitative index of the computational complexity. All ten algorithms had high numerical efficiency (all <4 ms except RS slope (94.07 ms and sixth power algorithms (8.25 ms. And OKB algorithm had the highest numerical efficiency (1.54 ms.

Pathways to a Four-Year Degree: Determinants of Degree Completion among Socioeconomically Disadvantaged Students.

Science.gov (United States)

Cabrera, Alberto F.; Burkum, Kurt R.; La Nasa, Steven M.

The High School Sophomore Cohort of 1980 followed nine different pathways to a 4-year college degree. These paths were formed by a combination of different levels of academic preparation secured in high school and the first type of postsecondary institution attended. The pathway most likely to lead to a 4-year degree is one defined by acquiring…

Ten years into the marshes – Hapalemur alaotrensis conservation ...

African Journals Online (AJOL)

Natural resource management problems typically involve a multitude of stakeholders with diverse sets of needs and interests, and often conflicting worldviews in an ... during the past ten years at Lake Alaotra, discussing the plan of action and challenges for environmental education, ecotourism and alternative livelihoods.

Eight to ten years follow-up after carotid endarterectomy

DEFF Research Database (Denmark)

Knudsen Rathenborg, Lisbet; Sillesen, H; Schroeder, T

1990-01-01

Follow-up information was obtained on 185 patients who consecutively underwent carotid endarterectomy eight to ten years previously. Doppler ultrasound examination was performed in 59 patients who were still alive and living within 100 miles of the hospital. Using lifetable analysis, the annual r...

75 FR 76003 - Tricor Ten Section Hub LLC; Notice of Availability of the Environmental Assessment for the...

Science.gov (United States)

2010-12-07

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. CP09-432-000] Tricor Ten Section Hub LLC; Notice of Availability of the Environmental Assessment for the Proposed Ten Section Gas... Commission) has prepared an environmental assessment (EA) for the Ten Section Gas Storage Project, in Kern...

Resolution 1540, ten years on

International Nuclear Information System (INIS)

Hautecouverture, Benjamin

2014-06-01

Adopted on the 28 April 2004 by the United Nations Security Council under Chapter VII of the UN Charter, Resolution 1540 is a composite tool that was hitherto unprecedented. To recap, States are bound to 'refrain from providing any form of support to non-State actors that attempt to develop, acquire, manufacture, possess, transport, transfer or use nuclear, chemical or biological weapons and their means of delivery' (par. 1), and to prohibit and prevent non-State actors from the aforementioned through 'appropriate and effective' (par. 2,3) legal, judiciary, and administrative means. A Committee was established to which States had to submit a first report outlining the steps 'they have taken or intend to take to implement this resolution' (par. 4). This Committee was initially established for two years and has been regularly renewed since, and its mandate was extended in 2011 for ten years. It is not a surveillance mechanism. Finally, with the aim of remedying difficulties that certain States may experience in implementing the Resolution, 'States in a position to do so' are invited to offer assistance (par. 7). The level of the application of Resolution 1540 was originally based on a delicate three-pronged balance of obligation, good will, and partnership. It is not a matter of designating certain States to the rest of the international community, whilst avoiding that the exercise be limited to the submission of national reports, instead aiming to initiate a dynamic. The wager was a risky one. Ten years on, 90% of UN member States have submitted one or several implementation reports. 170 States and 50 international and regional organisations have taken part in outreach and implementation support events. Whatever quantitative or qualitative conclusions that can be reached, we should continue to promote the Re-solution's universal adoption, and to ensure that the implementation of its provisions is undertaken in a lasting manner, taking account of the national

Transcutaneous electrical nerve stimulation (TENS) improves the diabetic cytopathy (DCP) via up-regulation of CGRP and cAMP.

Science.gov (United States)

Ding, Liucheng; Song, Tao; Yi, Chaoran; Huang, Yi; Yu, Wen; Ling, Lin; Dai, Yutian; Wei, Zhongqing

2013-01-01

The objective of this study was to investigate the effects and mechanism of Transcutaneous Electrical Nerve Stimulation (TENS) on the diabetic cytopathy (DCP) in the diabetic bladder. A total of 45 rats were randomly divided into diabetes mellitus (DM)/TENS group (n=15), DM group (n=15) and control group (n=15). The rats in the DM/TENS and TENS groups were electronically stimulated (stimulating parameters: intensity-31 V, frequency-31 Hz, and duration of stimulation of 15 min) for three weeks. Bladder histology, urodynamics and contractile responses to field stimulation and carbachol were determined. The expression of calcitonin gene-related peptide (CGRP) was analyzed by RT-PCR and Western blotting. The results showed that contractile responses of the DM rats were ameliorated after 3 weeks of TENS. Furthermore, TENS significantly increased bladder wet weight, volume threshold for micturition and reduced PVR, V% and cAMP content of the bladder. The mRNA and protein levels of CGRP in dorsal root ganglion (DRG) in the DM/TENS group were higher than those in the DM group. TENS also significantly up-regulated the cAMP content in the bladder body and base compared with diabetic rats. We conclude that TENS can significantly improve the urine contractility and ameliorate the feeling of bladder fullness in DM rats possibly via up-regulation of cAMP and CGRP in DRG.

Data processing potential ten years from now

International Nuclear Information System (INIS)

Zajde, C.

1982-01-01

What today is still experimental will tomorrow be routine. Use of emission tomography, automatic determination of regions of interest, generalisation of Fourrier phase and amplitude analysis, parametric images these will become routine medical protocols. The next ten years will see a saturation in the field of research and a stabilisation in system development. Equipment renewal will be seen from the same angle as in the automotive industry - more for reasons of wear and tear than for reasons of technical advancement

The use of transcutaneous electrical nerve stimulation (TENS) for pain relief in labour: a review of the evidence.

Science.gov (United States)

Bedwell, Carol; Dowswell, Therese; Neilson, James P; Lavender, Tina

2011-10-01

to assess the effects of transcutaneous electrical nerve stimulation (TENS) for pain relief in labour. studies were identified from a search of the Cochrane Pregnancy and Childbirth Group's Trials Register (November 2008). randomised controlled trials comparing women receiving TENS for pain relief in labour vs routine care or placebo devices. All types of TENS machines were included. two review authors assessed all trials identified by the search strategy, carried out data extraction and assessed risk of bias. 14 studies including 1256 women were included: 11 examined TENS applied to the back, two to acupuncture points and one to the cranium. Overall, there was little difference in satisfaction with pain relief or in pain ratings between TENS and control groups, although women receiving TENS to acupuncture points were less likely to report severe pain (risk ratio 0.41, 95% confidence interval 0.32-0.55). The majority of women using TENS would use it again in a future labour. There was no evidence that TENS had any impact on interventions and outcomes in labour. There was little information on outcomes for mothers and infants. No adverse events were reported. there is only limited evidence that TENS reduces pain in labour and it does not seem to have any impact on other outcomes for mothers or infants. The use of TENS at home in early labour has not been evaluated. Although the guidelines of the National Institute for Health and Clinical Excellence recommend that TENS should not be offered to women in labour, women appear to be choosing it and midwives are supporting them in their choice. Given the absence of adverse effects and the limited evidence base, it seems unreasonable to deny women that choice. More robust studies of effectiveness are needed. Copyright © 2009 Elsevier Ltd. All rights reserved.

Net Survey: "Top Ten Mistakes" in Academic Web Design.

Science.gov (United States)

Petrik, Paula

2000-01-01

Highlights the top ten mistakes in academic Web design: (1) bloated graphics; (2) scaling images; (3) dense text; (4) lack of contrast; (5) font size; (6) looping animations; (7) courseware authoring software; (8) scrolling/long pages; (9) excessive download; and (10) the nothing site. Includes resources. (CMK)

Idaho National Laboratory 2015-2023 Ten-Year Site Plan

Energy Technology Data Exchange (ETDEWEB)

Sheryl Morton; Elizabeth Connell; Bill Buyers; John Reisenauer; Rob Logan; Chris Ischay; Ernest Fossum; Paul Contreras; Joel Zarret; Steve Hill; Jon Tillo

2013-09-01

This Idaho National Laboratory (INL) Ten-Year Site Plan (TYSP) describes the strategy for accomplishing the long-term objective of sustaining the INL infrastructure to meet the Department of Energy Office of Nuclear Energy (DOE-NE) mission: to promote nuclear power as a resource capable of making major contributions in meeting the nation’s energy supply, environmental and energy security needs. This TYSP provides the strategy for INL to accomplish its mission by: (1) linking R&D mission goals to core capabilities and infrastructure requirements; (2) establishing a ten-year end-state vision for INL facility complexes; (3) identifying and prioritizing infrastructure needs and capability gaps; (4) establishing maintenance and repair strategies that allow for sustainment of mission-critical (MC) facilities; and (5) applying sustainability principles to each decision and action. The TYSP serves as the infrastructure-planning baseline for INL; and, though budget formulation documents are informed by the TYSP, it is not itself a budget document.

Multimodal Kelvin Probe Force Microscopy Investigations of a Photovoltaic WSe2/MoS2 Type-II Interface.

Science.gov (United States)

Almadori, Yann; Bendiab, Nedjma; Grévin, Benjamin

2018-01-10

Atomically thin transition-metal dichalcogenides (TMDC) have become a new platform for the development of next-generation optoelectronic and light-harvesting devices. Here, we report a Kelvin probe force microscopy (KPFM) investigation carried out on a type-II photovoltaic heterojunction based on WSe 2 monolayer flakes and a bilayer MoS 2 film stacked in vertical configuration on a Si/SiO 2 substrate. Band offset characterized by a significant interfacial dipole is pointed out at the WSe 2 /MoS 2 vertical junction. The photocarrier generation process and phototransport are studied by applying a differential technique allowing to map directly two-dimensional images of the surface photovoltage (SPV) over the vertical heterojunctions (vHJ) and in its immediate vicinity. Differential SPV reveals the impact of chemical defects on the photocarrier generation and that negative charges diffuse in the MoS 2 a few hundreds of nanometers away from the vHJ. The analysis of the SPV data confirms unambiguously that light absorption results in the generation of free charge carriers that do not remain coulomb-bound at the type-II interface. A truly quantitative determination of the electron-hole (e-h) quasi-Fermi levels splitting (i.e., the open-circuit voltage) is achieved by measuring the differential vacuum-level shift over the WSe 2 flakes and the MoS 2 layer. The dependence of the energy-level splitting as a function of the optical power reveals that Shockley-Read-Hall processes significantly contribute to the interlayer recombination dynamics. Finally, a newly developed time-resolved mode of the KPFM is applied to map the SPV decay time constants. The time-resolved SPV images reveal the dynamics of delayed recombination processes originating from photocarriers trapping at the SiO 2 /TMDC interfaces.

Physics to a degree

CERN Document Server

Thomas, EG

2014-01-01

Physics to a Degree provides an extensive collection of problems suitable for self-study or tutorial and group work at the level of an undergraduate physics course. This novel set of exercises draws together the core elements of an undergraduate physics degree and provides students with the problem solving skills needed for general physics' examinations and for real-life situations encountered by the professional physicist. Topics include force, momentum, gravitation, Bernoulli's Theorem, magnetic fields, blackbody radiation, relativistic travel, mechanics near the speed of light, radioactive

Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS/TEN): could retinoids play a causative role?

Science.gov (United States)

Mawson, Anthony R; Eriator, Ike; Karre, Sridhar

2015-01-12

Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS/TEN) are overlapping manifestations on a spectrum of acute drug-induced conditions associated with severe blistering, skin peeling, and multi-organ damage. TEN is an eruption resembling severe scalding, with ≥30% skin detachment. SJS is a mild form of TEN, characterized histologically by epidermal keratinocyte apoptosis with dermo-epidermal separation and extensive small blisters with <10% body surface skin detachment. The syndrome can be induced by numerous medications and typically occurs 1-4 weeks after the initiation of therapy. Granulysin is found in the lesions of patients with SJS/TEN and plays a significant pathogenic role in the condition, but the overall mechanisms linking medications, granulysin, and disease manifestations remain obscure. This paper reviews evidence suggesting that the different medications implicated in SJS/TEN have the common property of interacting and synergizing with endogenous retinoids (vitamin A and its congeners), in many instances causing the latter to accumulate in and damage the liver, the main storage organ for vitamin A. It is hypothesized that liver damage leads to the spillage of toxic retinoid compounds into the circulation, resulting in an endogenous form of hypervitaminosis A and cytotoxicity with widespread apoptosis, mediated by granulysin and recognized as SJS/TEN. Subject to testing, the model suggests that symptom worsening could be arrested at onset by lowering the concentration of circulating retinoids and/or granulysin via phlebotomy or plasmapheresis or by pharmacological measures to limit their expression.

Does a bachelor’s degree pay off?

DEFF Research Database (Denmark)

Neugebauer, Martin; Weiss, Felix

Academic education is generally rewarded by employers, but what happens to graduates if they are trained for two years less and have to compete with vocationally trained labor market entrants in a similar field of study? Focusing on Germany, we analyze labor market entries of individuals eligible...... for higher education, who either opted for newly introduced short bachelor’s degrees, or for well-established vocational degrees. Based on Microcensus data, we find that bachelor’s degrees from classical universities are associated with higher earnings and more prestigious jobs than initial vocational...... training degrees, and with higher prestige (but similar earnings) than further vocational degrees. However, bachelor’s degrees from universities are also related to higher risks of unemployment or fixed-term employment. Universities of applied sciences, which combine academic and practical training, offer...

New Records of Ten Species of the Family Ichneumonidae (Hymenoptera from South Korea

Directory of Open Access Journals (Sweden)

Choi, Jin-Kyung

2015-04-01

Full Text Available We report ten ichneumonids species new to South Korea. These species belong to eight subfamilies, Acaenitinae Forster, 1869, Diacritinae Townes, 1965, Ichneumoninae Latreille, 1802, Mesochorinae F$\\ddot{o}$ 수식 이미지rster, 1869, Microleptinae Townes, 1958, Pimplinae Wesmael, 1845, Tryponinae Shuckard, 1840, and Xoridinae Shuckard, 1840. Photographs of the habitus and diagnosis of ten newly recorded species, as well as host information are provided.

Noble gases in ten stone meteorites from Antarctica

International Nuclear Information System (INIS)

Weber, H.W.; Schultz, L.

1980-01-01

The concentrations and isotopic composition of noble gases have been determined in all ten stone meteorites recovered in Antarctica during 1976-1977 by a U.S.-Japanese expedition. From a comparison of spallogenic and radiogenic gas components it is concluded that the chondrites Mt. Baldr (a) and Mt. Baldr (b) belong to the same fall but that all other stone meteorites are individual finds. (orig.)

Astrometric studies of the regions BD + 17 degree 4946, BD -5 degree 3071, and Ross 730-1

International Nuclear Information System (INIS)

Russell, J.; Gatewood, G.

1975-01-01

Positions, proper motions, and absolute parallaxes were found for 46 stars in the regions of BD +17 degree4946, BD -5 degree3071, and Ross 730-1. BD +17 degree4946 showed some evidence of irregular variations in position and magnitude. The residuals for Ross 730-1 were used in a preliminary study to test for an appropriate weighting system; a weak weighting system was indicated. (auth)

Exact sampling of graphs with prescribed degree correlations

Science.gov (United States)

Bassler, Kevin E.; Del Genio, Charo I.; Erdős, Péter L.; Miklós, István; Toroczkai, Zoltán

2015-08-01

Many real-world networks exhibit correlations between the node degrees. For instance, in social networks nodes tend to connect to nodes of similar degree and conversely, in biological and technological networks, high-degree nodes tend to be linked with low-degree nodes. Degree correlations also affect the dynamics of processes supported by a network structure, such as the spread of opinions or epidemics. The proper modelling of these systems, i.e., without uncontrolled biases, requires the sampling of networks with a specified set of constraints. We present a solution to the sampling problem when the constraints imposed are the degree correlations. In particular, we develop an exact method to construct and sample graphs with a specified joint-degree matrix, which is a matrix providing the number of edges between all the sets of nodes of a given degree, for all degrees, thus completely specifying all pairwise degree correlations, and additionally, the degree sequence itself. Our algorithm always produces independent samples without backtracking. The complexity of the graph construction algorithm is {O}({NM}) where N is the number of nodes and M is the number of edges.

Sensory trigeminal ULF-TENS stimulation reduces HRV response to experimentally induced arithmetic stress: A randomized clinical trial.

Science.gov (United States)

Monaco, Annalisa; Cattaneo, Ruggero; Ortu, Eleonora; Constantinescu, Marian Vladimir; Pietropaoli, Davide

2017-05-01

Ultra Low Frequency Transcutaneous Electric Nervous Stimulation (ULF-TENS) is extensively used for pain relief and for the diagnosis and treatment of temporomandibular disorders (TMD). In addition to its local effects, ULF-TENS acts on the autonomic nervous system (ANS), with particular reference to the periaqueductal gray (PAG), promoting the release of endogenous opioids and modulating descending pain systems. It has been suggested that the PAG participates in the coupling between the emotional stimulus and the appropriate behavioral autonomic response. This function is successfully investigated by HRV. Therefore, our goal is to investigate the effects of trigeminal ULF-TENS stimulation on autonomic behavior in terms of HRV and respiratory parameters during an experimentally-induced arithmetic stress test in healthy subjects. Thirty healthy women between 25 and 35years of age were enrolled and randomly assigned to either the control (TENS stimulation off) or test group (TENS stimulation on). Heart (HR, LF, HF, LF/HF ratio, DET, RMSSD, PNN50, RR) and respiratory (BR) rate were evaluated under basal, T1 (TENS off/on), and stress (mathematical task) conditions. Results showed that HRV parameters and BR significantly changed during the arithmetic stress paradigm (pTENS and control group could be discriminated only by non-linear HRV data, namely RR and DET (p=0.038 and p=0.027, respectively). During the arithmetic task, LF/HF ratio was the most sensitive parameter to discriminate between groups (p=0.019). Our data suggest that trigeminal sensory ULF-TENS reduces the autonomic response in terms of HRV and BR during acute mental stress in healthy subjects. Future directions of our work aim at applying the HRV and BR analysis, with and without TENS stimulation, to individuals with dysfunctional ANS among those with TMD. Copyright © 2017 Elsevier Inc. All rights reserved.

The Top Ten Algorithms in Data Mining

CERN Document Server

Wu, Xindong

2009-01-01

From classification and clustering to statistical learning, association analysis, and link mining, this book covers the most important topics in data mining research. It presents the ten most influential algorithms used in the data mining community today. Each chapter provides a detailed description of the algorithm, a discussion of available software implementation, advanced topics, and exercises. With a simple data set, examples illustrate how each algorithm works and highlight the overall performance of each algorithm in a real-world application. Featuring contributions from leading researc

ALICE Zero Degree Calorimeter

CERN Multimedia

De Marco, N

2013-01-01

Two identical sets of calorimeters are located on both sides with respect to the beam Interaction Point (IP), 112.5 m away from it. Each set of detectors consists of a neutron (ZN) and a proton (ZP) Zero Degree Calorimeter (ZDC), positioned on remotely controlled platforms. The ZN is placed at zero degree with respect to the LHC beam axis, between the two beam pipes, while the ZP is positioned externally to the outgoing beam pipe. The spectator protons are separated from the ion beams by means of the dipole magnet D1.

Ten-year-olds' reflections on their life in preschool

DEFF Research Database (Denmark)

Broström, Stig

2016-01-01

What do children think of their time in preschool? In the present study, twelve ten-year-old children collected data from their classmates. The children tend to remember their friends, and reflect on what games they played and with whom. Only about one in three respondents even mentioned the day...

Changes in users' Web search performance after ten years ...

African Journals Online (AJOL)

The changes in users' Web search performance using search engines over ten years was investigated in this study. Matched data obtained from samples in 2000 and 2010 were used for the comparative analysis. The patterns of Web search engine use suggested a dominance in using a particular search engine. Statistical ...

Research Degrees as Professional Education?

Science.gov (United States)

Barnacle, Robyn; Dall'Alba, Gloria

2011-01-01

There is an increasing trend within higher education and, more specifically, in higher degrees by research, to treat a professional skills set as a desirable graduate outcome. The increasing value that is being placed on a professional skills set in large part reflects growing interest around the world in the role of research degrees in labour…

Design and modeling of inductors, capacitors and coplanar waveguides at tens of GHz frequencies

CERN Document Server

Aryan, Naser Pour

2015-01-01

This book describes the basic principles of designing and modelling inductors, MIM capacitors and coplanar waveguides at frequencies of several tens of GHz. The author explains the design and modelling of key, passive elements, such as capacitors, inductors and transmission lines that enable high frequency MEMS operating at frequencies in the orders of tens of GHz.

Using automated environmental management information systems to enable compliance: Ten questions to answer before selecting a software system

Energy Technology Data Exchange (ETDEWEB)

Gilbert, J.B.

1999-07-01

As technology invades the arena of environmental information management, hundreds of software packages have become available in the marketplace. How does the already overwhelmed environmental manager or IT professional decide what's right for the organization? Is there a software package that meets the needs of the organization, and is there a successful way to implement the system? Does this require abandoning existing systems with which users are comfortable? Can the system really save time and/or money? This paper discusses three topics: What drives the need for a system; Ten questions to aid in selecting a system that is right for your organization; and enabling technology and software systems available today, and the future application of technology to environmental data management. Motivating factors for EMIS include regulatory, business and IT drivers. Because of the ever-increasing regulatory burden, the need to demonstrate compliance often is the strongest driver. But they cannot ignore business and IT drivers from the discussion, especially with issues such as Enterprise Resource Planning and The Year 2000 impacting many systems projects. Before selecting a system, the organization should address, at a minimum, the following ten issues: (1) Organization objectives; (2) Organization readiness; (3) High-level processes to be automated; (4) Integration and interfaces; (5) User community and needs; (6) Technical requirements; (7) Degree of customization; (8) Project timing; (9) Implementation resource needs; and (10) System justification. Today, there are hundreds of EH and S software packages available too help automate daily business processes. Only a few are multimedia packages, and all require significant implementation efforts. The EMIS market is still evolving, and software vendors continue to enhance product features and usability.

Measurement of the oxidation of spent fuel between 140/degree/ and 225/degree/C by thermogravimetric analysis

International Nuclear Information System (INIS)

Woodley, R.E.; Einziger, R.E.; Buchanan, H.C.

1988-09-01

A series of PWR spent fuel samples from Turkey Point Unit 3 have been oxidized at temperatures between 140/degree/ and 225/degree/C in air atmospheres with dew points between 14.5/degree/ and /minus/70/degree/C, using a thermogravimetric analysis system (TGA). Tests lasted between 400 and 2100 hours. At the conclusion of a test, the atmosphere was sampled to determine the release of fission gas during testing, and the fuel samples were analyzed for microstructural changes. It appears that the mechanism for oxidation of spent fuel to U/sub 3/O/sub 7/ takes place in two steps that occur somewhat simultaneously. Oxygen migrates along the grain boundaries, which are oxidized and enlarged. The grains oxidize by the inward progression of a layer of U/sub 4/O/sub 9/ saturated with oxygen. A simplified model of the mechanism, which considers oxygen diffusion through the product layer as the rate-controlling step, yields an activation energy of 27 /plus minus/ 4 kcal/mol. Moisture, between dew points of /minus/70/degree/ to +14.5/degree/C, i.e., water vapor partial pressures varying over four orders of magnitude, had no significant effect on the oxidation rate. 34 refs., 12 figs., 6 tabs

Six to Ten Digits Multiplication Fun Learning Using Puppet Prototype

Science.gov (United States)

Islamiah Rosli, D.'oria; Ali, Azita; Peng, Lim Soo; Sujardi, Imam; Usodo, Budi; Adie Perdana, Fengky

2017-01-01

Logic and technical subjects require students to understand basic knowledge in mathematic. For instance, addition, minus, division and multiplication operations need to be mastered by students due to mathematic complexity as the learning mathematic grows higher. Weak foundation in mathematic also contribute to high failure rate in mathematic subjects in schools. In fact, students in primary schools are struggling to learn mathematic because they need to memorize formulas, multiplication or division operations. To date, this study will develop a puppet prototyping for learning mathematic for six to ten digits multiplication. Ten participants involved in the process of developing the prototype in this study. Students involved in the study were those from the intermediate class students whilst teachers were selected based on their vast knowledge and experiences and have more than five years of experience in teaching mathematic. Close participatory analysis will be used in the prototyping process as to fulfil the requirements of the students and teachers whom will use the puppet in learning six to ten digit multiplication in mathematic. Findings showed that, the students had a great time and fun learning experience in learning multiplication and they able to understand the concept of multiplication using puppet. Colour and materials of the puppet also help to attract student attention during learning. Additionally, students able to visualized and able to calculate accurate multiplication value and the puppet help them to recall in multiplying and adding the digits accordingly.

The comparison of application of two different frequencies of TENS on excitability of Hoffmann reflex

Directory of Open Access Journals (Sweden)

Akbari M

2001-08-01

Full Text Available The aim of this investigation is to compare the effect of applying two transcutaneous electrical nerve stimulation (TENS current with different frequencies (2 Hz & 100 Hz on Hoffmann reflex recorded from gastrosoleus muscle of healthy people. Forty female subjects between 20 to 30 years of age were participated in this quasi-experimental design. Twenty of them were exposed to the 100 Hz current and the remaining 20 to 2 Hz current on dermatome S1 root. The excitability of the alpha motoneurone was measured by H-reflex amplitude (peak to peak max/2 before and after the application of the TENS current for 30 minutes. The reflex was recorded and at measured before (TO and after the application of TENS at different times (T1, T% and T10 up to 10 minutes. The mean values were compared by multiple paired T test (alpha=0.00825. The results indicate a considerable decrement in Hoffmann reflex amplitude after application of 100 Hz current in comarison with that of before the application. The effect last for 10 minutes after the TENS application, whereas the application of 2 Hz current results in increment of the Hoffmann reflex amplitude. The 5 and 10 minutes interval test dose not show any significance and the results were attenuated befor 5 minutes. As a conclusion high frequency of TENS (100 Hz has an inhibitory effect on excitability of alpha motor neurone reflex lasting for 10 minutes, while low frequency of TENS (2 Hz has an facilatory effect on the same motoneurone with short lasting effect.

Electronic structure and optical properties of (BeTen/(ZnSem superlattices

Directory of Open Access Journals (Sweden)

Caid M.

2016-03-01

Full Text Available The structural, electronic and optical properties of (BeTen/(ZnSem superlattices have been computationally evaluated for different configurations with m = n and m≠n using the full-potential linear muffin-tin method. The exchange and correlation potentials are treated by the local density approximation (LDA. The ground state properties of (BeTen/(ZnSem binary compounds are determined and compared with the available data. It is found that the superlattice band gaps vary depending on the layers used. The optical constants, including the dielectric function ε(ω, the refractive index n(ω and the refractivity R(ω, are calculated for radiation energies up to 35 eV.

A Gadamerian Phenomenological Study Examining the Meaning of Having a Bachelor's Degree Expressed by Associate Degree Nurses (ADN) Who Educationally Transitioned to a Baccalaureate Degree in Nursing (BSN)

Science.gov (United States)

Sauld, Jill Pierpont

2017-01-01

Since the inception of associate degree nursing programs, professional nursing conversations and debate have grappled with reckoning differences between the associate degree in nursing (ADN) and the bachelor's degree in nursing (BSN). Research reporting better patient outcomes with more baccalaureate prepared nurses has been a driving force for…

Clinical and economic impact of TENS in patients with chronic low back pain: analysis of a nationwide database.

Science.gov (United States)

Pivec, Robert; Stokes, Michael; Chitnis, Abhishek S; Paulino, Carl B; Harwin, Steven F; Mont, Michael A

2013-12-01

This study evaluated patients who were given transcutaneous electrical nerve stimulation (TENS) compared with a matched group without TENS prior to intervention and at 1-year follow-up. Patients who were treated with TENS had significantly fewer hospital and clinic visits, used less diagnostic imaging (31 vs 46 events per 100 patients), had fewer physical therapy visits (94 vs 107), and required less back surgery (7.5 vs 9.2 surgeries) than patients receiving other treatment modalities. Total annual costs for chronic low back pain patients without neurological involvement were lower in TENS patients ($17,957 vs $17,986 for non-TENS), even when the cost of the device was taken into account.

Cosmic strings

Energy Technology Data Exchange (ETDEWEB)

Copeland, E. J. [Sussex (United Kingdom)

1991-07-15

The past decade has seen a developing interplay between elementary particle physics and cosmology. The former has had great success in demonstrating the unification of the weak and electromagnetic forces at energies just above 250 GeV (1016 degrees Kelvin). The 'Standard Model' of particle physics seems to describe accurately the interactions of quarks and leptons at and below these energies, as demonstrated daily in CERN's LEP electron-positron collider.

Ten years of x-ray holography

International Nuclear Information System (INIS)

Faigel, G.; Bortel, G.; Tegze, M.; Fadley, C.S.; Simionovici, A.S.

2007-01-01

With the appearance of nano-science the role of local methods has become more and more important. Hard x-ray holography based on the inside reference point concept is a local probe of the atomic order in solids. It gives the 3D real space image of atoms without the phase ambiguity inherent to diffraction methods. In this paper a brief description of the basics of hard x-ray holography is given. The last ten years' experimental and evaluation-related developments are reviewed. We also introduce different variants of the method, such as Bremsstrahlung and gamma ray holography (GRH). The power of the method is illustrated by examples. We outline new directions and future possibilities. (authors)

The Journal of Real Estate Research: A Ten-Year Review

OpenAIRE

G. Donald Jud

1996-01-01

This paper provides a catalogue of the papers published in The Journal of Real Estate Research during its first ten years of operation, 1986-96. Articles are indexed by volume and number of The Journal, author, title, and subject.

Nuclear engineering enrollments and degrees, 1981

International Nuclear Information System (INIS)

Little, J.R.; Shirley, D.L.

1982-05-01

This report presents data on the number of students enrolled and the degrees awarded in academic year 1980-81 from 73 US institutions offering degree programs in nuclear engineering or nuclear options within other engineering fields. Presented here are historical data for the last decade, which provide information such as trends by degree level, foreign national student participation, female and minority student participation, and placement of graduates. Also included is a listing of the universities by type of program and number of students

TENS to the Lateral Aspect of the Knees During Stance Attenuates Postural Sway in Young Adults

Directory of Open Access Journals (Sweden)

Yocheved Laufer

2007-01-01

Full Text Available Somatosensory input is known to be essential for postural control. The present study examined the effects on postural sway of sensory input delivered via transcutaneous electrical nerve stimulation (TENS applied to the knees during stance. Electrodes from a dual-channel portable TENS unit were adhered to the skin overlying the lateral and medial aspect of both knees of 20 young healthy volunteers (mean age 24.0 years, standard deviation 4.0. Postural sway parameters were obtained during static bipedal stance with an AMTI force platform. Four stimulation conditions were tested with eyes open and with eyes closed: no TENS; TENS applied bilaterally; and TENS applied to either the right or the left knee. Participants underwent two eight-trial blocks, with each trial lasting 30 seconds. The order of conditions was randomized for each participant. Stimulation consisted of a biphasic symmetrical stimulus delivered at the sensory detection level, with a pulse duration of 200μsec and a pulse frequency of 100Hz. The application of TENS induced significant reductions in mean sway velocity and in the medio-lateral dispersion of the center of pressure, with no corresponding effect on the anterior-posterior dispersion. These findings suggest that electrical stimulation delivered at the sensory detection level to the lateral aspects of the knees may be effective in improving balance control, and that this effect may be directionally specific.

Combined 30-degree bevel up and down technique against 0-degree phaco tip for phacoemulsification surgery of hard cataracts

Directory of Open Access Journals (Sweden)

Joshi RS

2017-06-01

Full Text Available Rajesh Subhash Joshi, Sonal Jayant Muley Department of Ophthalmology, Vasantrao Naik Government Medical College, Yavatmal, Maharashtra, India Purpose: To evaluate the effective phaco time (EPT, cumulative dissipated energy (CDE and nucleus emulsification time (NET as phaco parameters with 0- and 30-degree phaco tip. Patients and methods: This prospective, interventional and observational case series included 294 patients scheduled for cataract removal by phacoemulsification technique. Patients with nuclear cataracts of grade 4 and 5 nuclear opalescence of Lens Opacities Classification System III were included in the study. Patients were consecutively allocated to phaco chop technique with 0-degree (0-degree group, n=147 and combined bevel up and down position using 30-degree phaco tip (combined bevel up/down group, n=147. The 0-degree group had phacoemulsification with 0-degree phaco tip, while the 30-degree group had chopping of the nucleus with bevel down phaco tip and emulsification of nuclear fragments was accomplished with bevel up tip. EPT, CDE, NET and intraoperative complications were noted and compared between the groups using analysis of variance. Results: Average EPT, CDE and NET were lower in the 30-degree group than in the 0-degree group. However, no statistically significant difference was found in EPT (P=0.0733, CDE (P=0.0663 and NET (P=0.0633 between the two groups. No serious intraoperative complications were noted. The anterior chamber was maintained throughout the procedure in both groups. No patients had wound burn and miosis during the procedure. None of the patients developed bullous keratopathy, uveitis and cystoid macular edema during the follow-up period. Conclusion: Combined bevel up and down 30-degree tip can yield effective hard nucleus phacoemulsification. Bevel down tip of 30-degree helps in effective chopping and bevel up tip assists in emulsification of the nuclear fragments. Although combined bevel up and down 30

Variation in meroplankton along 78 degrees E Meridian

Digital Repository Service at National Institute of Oceanography (India)

Balachandran, T.; Peter, K.J.

Variations along the meridian 78 degrees E between 8 degrees N and 25 degrees S, based on 43 zooplankton samples were studied. Fish larvae exhibited fluctuations in abundance (26 to 57 specimens/IOSN haul) in the three zones studied (8 degrees N-5...

Does the Russian Economy Need Human Capital? Ten Doubts

Science.gov (United States)

Gimpelson, V. E.

2016-01-01

It is generally accepted that human capital is an important factor in economic growth, but its impact on growth depends on the demand for education and skills on the labor market. Demand for human capital is largely determined by the institutional environment that governs the basic conditions for economic activity. The author expresses ten doubts…

Japanese hospitals--culture and competition: a study of ten hospitals.

Science.gov (United States)

Anbäcken, O

1994-01-01

Japanese health care is characterized by a pluralistic system with a high degree of private producers. Central government regulates the prices and the financing system. All citizens are covered by a mandatory employment-based health insurance operating on a non-profit basis. The consumer has a free choice of physician and hospital. A comparison between Japan, Sweden and some other countries shows significant dissimilarities in the length of stay, number of treatments per hospital bed and year and the staffing of hospitals. About 80 per cent of the hospitals and 94 per cent of the clinics are privately owned. The typical private hospital owned by a physician has less than 100 beds. In this paper, data collected (1992/93) in an empirical study of Japanese hospitals and their leadership is presented. Also discussed are the hospitals' style of management, tools and strategies for competition and competences--personal and formal skills required of the leadership in the hospital. There follows a study of ten hospitals, among which hospital directors and chief physicians were interviewed. Interviews are also made with key persons in the Ministry of Health and Welfare and other organizations in the health care field. The result is also analysed from a cultural perspective--'what kind of impact does the Japanese culture have on the health care organization?' and/or 'what kind of sub-culture is developed in the Japanese hospitals'. Some comparisons are made with Sweden, USA, Canada and Germany. The different roles of the professions in the hospital are included in the study as well as the incentives for different kinds of strategies--specialization, growing in size, investments in new equipment, different kind of ownership and hospitals. Another issue discussed is the attempt to uncover whether there is an implicit distribution of specialties--silent agreements between hospitals, etc.