Paradigms or Toolkits? Philosophical and Methodological Positions as Heuristics for Mixed Methods Research

ERIC Educational Resources Information Center

Maxwell, Joseph A.

2011-01-01

In this article, the author challenges the validity and usefulness of the concept of "paradigm," as this term has been used in the social sciences generally, and specifically in the debates over research methods. He emphasizes that in criticizing what he sees as the misuse of the paradigm concept, he is not arguing for dismissing or ignoring…

Optical model potentials for 6He+64Zn from 63Cu(7Li,6He)64Zn reactions

NASA Astrophysics Data System (ADS)

Yang, L.; Lin, C. J.; Jia, H. M.; Wang, D. X.; Sun, L. J.; Ma, N. R.; Yang, F.; Wu, Z. D.; Xu, X. X.; Zhang, H. Q.; Liu, Z. H.; Bao, P. F.

2017-03-01

Angular distributions of the transfer reaction 63Cu(7Li,6He )64Zn were measured at Elab(7Li) =12.67 , 15.21, 16.33, 23.30, 27.30, and 30.96 MeV. With the interaction potentials of the entrance channel 7Li+63Cu obtained from elastic scattering data as input, the optical potentials of the halo nuclear system 6He+64Zn in the exit channel were extracted by fitting the experimental data with the distorted-wave Born approximation (DWBA) and coupled reaction channels (CRC) methods, respectively. The results show that the threshold anomaly presents in the weakly bound system of 7Li+63Cu and the dispersion relation can be adopted to describe the connection between the real and imaginary potentials, while both the real and imaginary potentials nearly keep constant within the researched energy region for the halo system of 6He+64Zn . Moreover, calculations by the potentials extracted from the CRC method can reproduce the experimental elastic scattering of the 6He+64Zn system rather well, but those by the potentials from the DWBA method cannot, where the couplings between 7Li and 6He are absent. This work verifies the validity of the transfer method in the medium-mass target region and lays a solid foundation for the further study of optical potentials for exotic nuclear systems.

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

Zaka, Fowzia

This method describes the characterization of HE powders by Scanning Electron Microscopy (SEM). HE particles are dispersed onto an aluminum standard SEM specimen mount. Electron micrographs are collected at various magnifications (150 to 10,000 X) depending on HE particle size.

Methods of Hematoxylin and Erosin Image Information Acquisition and Optimization in Confocal Microscopy

PubMed Central

Yoon, Woong Bae; Kim, Hyunjin; Kim, Kwang Gi; Choi, Yongdoo; Chang, Hee Jin

2016-01-01

Objectives We produced hematoxylin and eosin (H&E) staining-like color images by using confocal laser scanning microscopy (CLSM), which can obtain the same or more information in comparison to conventional tissue staining. Methods We improved images by using several image converting techniques, including morphological methods, color space conversion methods, and segmentation methods. Results An image obtained after image processing showed coloring very similar to that in images produced by H&E staining, and it is advantageous to conduct analysis through fluorescent dye imaging and microscopy rather than analysis based on single microscopic imaging. Conclusions The colors used in CLSM are different from those seen in H&E staining, which is the method most widely used for pathologic diagnosis and is familiar to pathologists. Computer technology can facilitate the conversion of images by CLSM to be very similar to H&E staining images. We believe that the technique used in this study has great potential for application in clinical tissue analysis. PMID:27525165

Theoretical investigation of the He4Br2 conformers.

PubMed

Valdés, Álvaro; Prosmiti, Rita; Villarreal, Pablo; Delgado-Barrio, Gerardo

2012-07-05

Full dimensional quantum dynamics calculations of the three lowest isomers of the He(4)Br(2) van der Waals molecule in its ground electronic state are reported. The calculations are performed using the multiconfiguration time-dependent Hartree (MCTDH) method and a realistic potential form that includes the sum of three body ab initio coupled-cluster single double triple [CCSD(T)] He-Br(2) interactions plus the He-He and Br-Br interactions. This potential exhibits several multiple minima, with the three lowest ones lying very close in energy, just within 2 cm(-1). Such small differences are also found in the calculated binding energies of the three most stable conformers, indicating the floppiness of the system and, thus, the need of accurate potential forms and quantum full dynamics methods to treat this kind of complexes. The 12 dimensional results reported in this work present benchmark data and, thus, can serve to evaluate approximate methods aiming to describe higher order rare gas-dihalogen (N > 4) complexes. A comparison with previous studies using different potential forms and approaches to the energetics for the He(4)Br(2) cluster is also presented.

Norman Ramsey and the Separated Oscillatory Fields Method

Science.gov Websites

methods of investigation; in particular, he contributed many refinements of the molecular beam method for the study of atomic and molecular properties, he invented the separated oscillatory field method of atomic and molecular spectroscopy and it is the practical basis for the most precise atomic clocks

In-Situ Apatite Laser Ablation U-Th-Sm/He Dating, Methods and Challenges

NASA Astrophysics Data System (ADS)

Pickering, J. E.; Matthews, W.; Guest, B.; Hamilton, B.; Sykes, C.

2015-12-01

In-situ, laser ablation U-Th-Sm/He dating is an emerging technique in thermochronology that has been proven as a means to date zircon and monzonite1-5. In-situ U-Th-Sm/He thermochronology eliminates many of the problems and inconveniences associated with traditional, whole grain methods, including; reducing bias in grain selection based on size, shape and clarity; allowing for the use of broken grains and grains with inclusions; avoiding bad neighbour effects; and eliminating safety hazards associated with dissolution. In-situ apatite laser ablation is challenging due to low concentrations of U and Th and thus a low abundance of radiogenic He. For apatite laser ablation to be effective the ultra-high-vacuum (UHV) line must have very low and consistent background levels of He. To reduce He background, samples are mounted in a UHV stable medium. Our mounting process uses a MicroHePP (Microscope Mounted Heated Platen Press) to press samples into FEP (fluorinated ethylene propylene) bonded to an aluminum backing plate. Samples are ablated using a Resonetics 193 nm excimer laser and liberated He is measured using a quadrupole mass spectrometer on the ASI Alphachron noble gas line; collectively this system is known as the Resochron. The ablated sites are imaged using a Zygo Zescope optical profilometer and ablated pit volume measured using PitVol, a custom MatLab algorithm developed to enable precise and unbiased measurement of the ablated pit geometry. We use the well-characterized Durango apatite to demonstrate the accuracy and precision of the method. He liberated from forty-two pits, having volumes between 1700 and 9000 um3, were measured using the Resochron. The ablated sites were imaged using a Zygo Zescope optical profilometer and ablated pit volume measured using PitVol. U, Th and Sm concentrations were measured by laser ablation and the U-Th-Sm/He age calculated by standard age equation. An age of 33.8±0.31 Ma was determined and compares well with conventional U-Th/He methods, whole grain degassing and dissolution, that produced an age of 32.73±0.47 Ma for chips of the same Durango crystal. Further dating of other well characterized apatite crystals will be used to test the robustness of the method.

Radium isotopes in groundwater around Fuji Volcano, Japan -application for groundwater dating on volcanic area-

NASA Astrophysics Data System (ADS)

Ohta, T.; Mahara, Y.

2010-12-01

Young groundwater dating less than 100 years is possible to be obtained from environmental radioactivity with short half life, 3H+3He, 85Kr, or chemical material, CFC-12. The 3H+3He dating method is excellent method to estimate the residence time of shallow groundwater. The one of advantage of the method is small sample volume. The 3He in groundwater is originated by 3 sources, tritiogenic He, mantle He, radiogenic He produced in rock. Especially, as the contribution of the mantle He is greater than the radiogenic and triogenic, when 3H+3He dating apply for groundwater dating on volcanic area, we have to determine ratio of 3 sources. On the other hand, as 85Kr is only originated from atmosphere, it is excellent groundwater dating tracer on volcanic area. However, as 85Kr is ultra low concentration in groundwater, 85Kr is needed to separate from large amount of ground water about 10^5 L. Young groundwater dating by these methods has both advantages and disadvantages, but the disadvantages of the individual methods can be offset by using multiple tracers. Development of a lot of groundwater dating techniques is desired. Therefore, an application of radium isotopes which is simple origin to groundwater dating on volcanic area was tried. Ra-228 and Ra-226 are progenies of Th and U, respectively. The 228Ra/226Ra in ground waters depends on the Th/U in the relevant rocks. As the 228Ra and 226Ra in shallow groundwater on volcanic area are originated from only rock, and the collection of radium isotopes from groundwater is easier than that of 85Kr, implying that it is possible to be good tracer for volcanic area. We aim that groundwater age obtain from 228Ra/226Ra in groundwater and relevant rock on volcanic area. We determined that 228Ra/226Ra observed with river waters and the relevant rocks. The method applied for Kakitagawa around Fuji Volcano, Japan. The relevant rock of Kakitagawa is Mishima lava flow. Our method compared with 3H+3He dating. The residence time of Kakitagawa river water estimated from the 228Ra/226Ra activity ratio in river water and relevant rock is from 12-20 years, and agree well with 3H+3He age, suggesting that 228Ra/226Ra of groundwater could be used as a tool of residence time estimation of groundwater on volcanic area.

RCNP Project on Polarized {sup 3}He Ion Sources - From Optical Pumping to Cryogenic Method

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

Tanaka, M.; Inomata, T.; Takahashi, Y.

2009-08-04

A polarized {sup 3}He ion source has been developed at RCNP for intermediate and high energy spin physics. Though we started with an OPPIS (Optical Pumping Polarized Ion Source), it could not provide highly polarized {sup 3}He beam because of fundamental difficulties. Subsequently to this unhappy result, we examined novel types of the polarized {sup 3}He ion source, i.e., EPPIS (Electron Pumping Polarized Ion Source), and ECRPIS (ECR Polarized Ion Source) experimentally or theoretically, respectively. However, attainable {sup 3}He polarization degrees and beam intensities were still insufficient for practical use. A few years later, we proposed a new idea formore » the polarized {sup 3}He ion source, SEPIS (Spin Exchange Polarized Ion Source) which is based on enhanced spin-exchange cross sections at low incident energies for {sup 3}He{sup +}+Rb, and its feasibility was experimentally examined.Recently, we started a project on polarized {sup 3}He gas generated by the brute force method with low temperature (approx4 mK) and strong magnetic field (approx17 T), and rapid melting of highly polarized solid {sup 3}He followed by gasification. When this project will be successful, highly polarized {sup 3}He gas will hopefully be used for a new type of the polarized {sup 3}He ion source.« less

Ernst Mach and George Sarton's Successors: The Implicit Role Model of Teaching Science in USA and Elsewhere, Part II

ERIC Educational Resources Information Center

Siemsen, Hayo

2013-01-01

George Sarton had a strong influence on modern history of science. The method he pursued throughout his life was the method he had discovered in Ernst Mach's "Mechanics" when he was a student in Ghent. Sarton was in fact throughout his life implementing a research program inspired by the epistemology of Mach. Sarton in turn inspired many…

BAYESIAN ESTIMATION OF THERMONUCLEAR REACTION RATES

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

Iliadis, C.; Anderson, K. S.; Coc, A.

The problem of estimating non-resonant astrophysical S -factors and thermonuclear reaction rates, based on measured nuclear cross sections, is of major interest for nuclear energy generation, neutrino physics, and element synthesis. Many different methods have been applied to this problem in the past, almost all of them based on traditional statistics. Bayesian methods, on the other hand, are now in widespread use in the physical sciences. In astronomy, for example, Bayesian statistics is applied to the observation of extrasolar planets, gravitational waves, and Type Ia supernovae. However, nuclear physics, in particular, has been slow to adopt Bayesian methods. We presentmore » astrophysical S -factors and reaction rates based on Bayesian statistics. We develop a framework that incorporates robust parameter estimation, systematic effects, and non-Gaussian uncertainties in a consistent manner. The method is applied to the reactions d(p, γ ){sup 3}He, {sup 3}He({sup 3}He,2p){sup 4}He, and {sup 3}He( α , γ ){sup 7}Be, important for deuterium burning, solar neutrinos, and Big Bang nucleosynthesis.« less

The making of a medical entomologist.

PubMed

Service, Mike W

2010-01-01

This article describes the childhood of Mike Service, his very early interest in insects, his time at Imperial College, London University, and his career in Nigeria studying the taxonomy and biology of anopheline malaria vectors. On his return to England he became increasingly interested in the ecology and population dynamics of hematophagous insects. After almost eight years undertaking only research, he joined the Liverpool School of Tropical Medicine, where he was involved in lecturing as well as research and engaged in frequent overseas travel mainly to Africa, Central and South America, and Asia. On retirement he retains an active interest in medical entomology. Although he undertook a considerable amount of taxonomic work on mosquitoes, he believes his most important, and possibly influential, work was introducing ecological methods that were used by agricultural scientists to the study of mosquitoes. For example, the construction of life tables, calculating the percentage mortality of pre-adult mosquitoes, and the identification of predators by serological methods.

Quality of HE in Private Universities of Bangladesh: The Four Fundamental Perspectives

ERIC Educational Resources Information Center

Alam, Gazi Mahabubul; Parvin, Morsheda

2017-01-01

Since its inception, Higher Education (HE) has always been playing a critical role for national development through the development of skilled manpower and intellectual civic society. Continuous paradigm shifting in HE in term of institutions' pattern and course delivery mode and method has always been the part of the process of HE transformation.…

Methods of Hematoxylin and Erosin Image Information Acquisition and Optimization in Confocal Microscopy.

PubMed

Yoon, Woong Bae; Kim, Hyunjin; Kim, Kwang Gi; Choi, Yongdoo; Chang, Hee Jin; Sohn, Dae Kyung

2016-07-01

We produced hematoxylin and eosin (H&E) staining-like color images by using confocal laser scanning microscopy (CLSM), which can obtain the same or more information in comparison to conventional tissue staining. We improved images by using several image converting techniques, including morphological methods, color space conversion methods, and segmentation methods. An image obtained after image processing showed coloring very similar to that in images produced by H&E staining, and it is advantageous to conduct analysis through fluorescent dye imaging and microscopy rather than analysis based on single microscopic imaging. The colors used in CLSM are different from those seen in H&E staining, which is the method most widely used for pathologic diagnosis and is familiar to pathologists. Computer technology can facilitate the conversion of images by CLSM to be very similar to H&E staining images. We believe that the technique used in this study has great potential for application in clinical tissue analysis.

Planungsmodelle und Planungsmethoden. Anhaltspunkte zur Strukturierung und Gestaltung von Planungsprozessen

NASA Astrophysics Data System (ADS)

Diller, Christian; Karic, Sarah; Oberding, Sarah

2017-06-01

The topic of this article ist the question, in which phases oft he political planning process planners apply their methodological set of tools. That for the results of a research-project are presented, which were gained by an examination of planning-cases in learned journals. Firstly it is argued, which model oft he planning-process is most suitable to reflect the regarded cases and how it is positioned to models oft he political process. Thereafter it is analyzed, which types of planning methods are applied in the several stages oft he planning process. The central findings: Although complex, many planning processes can be thouroughly pictured by a linear modell with predominantly simple feedback loops. Even in times of he communicative turn, concerning their set of tools, planners should pay attention to apply not only communicative methods but as well the classical analytical-rational methods. They are helpful especially for the understanding of the political process before and after the actual planning phase.

HeLM: a macrophyte-based method for monitoring and assessment of Greek lakes.

PubMed

Zervas, Dimitrios; Tsiaoussi, Vasiliki; Tsiripidis, Ioannis

2018-05-05

The Water Framework Directive (WFD) requires Member States to develop appropriate assessment methods for the classification of the ecological status of their surface waters. Mediterranean region has lagged behind in this task, so we propose here the first developed method for Greek lakes, Hellenic Lake Macrophyte (HeLM) assessment method. This method is based on two metrics, a modified trophic index and maximum colonization depth C max that quantify the degree of changes in lake macrophytic vegetation, as a response to eutrophication and general degradation pressures. The method was developed on the basis of a data set sampled from 272 monitoring transects in 16 Greek lakes. Sites from three lakes were selected as potential reference sites by using a screening process. Ecological quality ratios were calculated for each metric and for each lake, and ecological status class boundaries were defined. For the evaluation of effectiveness of the method, the correlations between individual metrics and final HeLM values and common pressure indicators, such as total phosphorus, chlorophyll a and Secchi depth, were tested and found highly significant and relatively strong. In addition, the ability of HeLM values and its individual metrics to distinguish between different macrophytic communities' structure was checked using aquatic plant life-forms and found satisfactory. The HeLM method gave a reliable assessment of the macrophytic vegetation's condition in Greek lakes and may constitute a useful tool for the classification of ecological status of other Mediterranean lakes.

What can Numerical Computation do for the History of Science? (Study of an Orbit Drawn by Newton on a Letter to Hooke)

NASA Astrophysics Data System (ADS)

Stuchi, Teresa; Cardozo Dias, P.

2013-05-01

Abstract (2,250 Maximum Characters): On a letter to Robert Hooke, Isaac Newton drew the orbit of a mass moving under a constant attracting central force. How he drew the orbit may indicate how and when he developed dynamic categories. Some historians claim that Newton used a method contrived by Hooke; others that he used some method of curvature. We prove geometrically: Hooke’s method is a second order symplectic area preserving algorithm, and the method of curvature is a first order algorithm without special features; then we integrate the hamiltonian equations. Integration by the method of curvature can also be done exploring geometric properties of curves. We compare three methods: Hooke’s method, the method of curvature and a first order method. A fourth order algorithm sets a standard of comparison. We analyze which of these methods best explains Newton’s drawing.

[Prof. Morawiecki: the oculist and outstanding expert in immunology, immunopathology and serology].

PubMed

Raczyńska, K; Iwaszkiewicz-Bilikiewicz, B

2000-01-01

Jerzy Morawiecki (1910-1997) was a man with versatile interests. Being an assistant of Professor Władysław Szumowski in the Jagiellonian University he published papers devoted to the history of medicine. After getting his medical degree in 1937 he worked in the Public Health Department in Warsaw under the very well known Ludwik Hirszfeld. There he carried out pioneer studies on the blood groups, the very beginning of a new science - immunology which moulded the scientific interests to which he was faithful for the rest of his life. Under the Nazi occupation of Warsaw he managed to send his paper on blood groups to Switzerland where it was published in 1941. Between 1946 and 1992 he published 18 papers in the field of immunology mainly of the eye. He did pioneer work on the precipitation of antigens and antibodies. The phenomenon of precipitation lines in the cornea is quoted in the literature as the "Morawiecki phenomenon" or as "Morawiecki' lines". He presented the original hypothesis of immunotherapy of intravitreal hemorrhages - the method of acceleration of hemorrhage absorption. The use of Anti-RhD antibodies subsequently became the most effective method of intraocular hemorrhages.

{alpha}+{sup 6,8}He resonant scattering and exotic structures in {sup 10,12}Be

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

Ito, Makoto; Itagaki, Naoyuki

2008-05-21

The {alpha}+{sup 6}He low-energy reactions and the structural changes of {sup 10}Be in the microscopic {alpha}+{alpha}+2N model are studied by the generalized two-center cluster model with the Kohn-Hulthen-Kato variation method. It is found that, in the inelastic scattering to the {alpha}+{sup 6}He(2{sub 1}{sup +}) channel, characteristic enhancements are expected as the results of the parity-dependent non-adiabatic dynamics. The similar method is applied to the resonant scattering of {alpha}+{sup 8}He, and the coupling with the compound configurations of {alpha}+{alpha}+4N are discussed.

Degassing of 3H/3He, CFCs and SF6 by denitrification: measurements and two-phase transport simulations.

PubMed

Visser, Ate; Schaap, Joris D; Broers, Hans Peter; Bierkens, Marc F P

2009-01-26

The production of N2 gas by denitrification may lead to the appearance of a gas phase below the water table prohibiting the conservative transport of tracer gases required for groundwater dating. We used a two-phase flow and transport model (STOMP) to study the reliability of 3H/3He, CFCs and SF6 as groundwater age tracers under agricultural land where denitrification causes degassing. We were able to reproduce the amount of degassing (R2=69%), as well as the 3H (R2=79%) and 3He (R2=76%) concentrations observed in a 3H/3He data set using simple 2D models. We found that the TDG correction of the 3H/3He age overestimated the control 3He/3He age by 2.1 years, due to the accumulation of 3He in the gas phase. The total uncertainty of degassed 3H/3He ages of 6 years (+/-2 sigma) is due to the correction of degassed 3He using the TDG method, but also due to the travel time in the unsaturated zone and the diffusion of bomb peak 3He. CFCs appear to be subject to significant degradation in anoxic groundwater and SF6 is highly susceptible to degassing. We conclude that 3H/3He is the most reliable method to date degassed groundwater and that two-phase flow models such as STOMP are useful tools to assist in the interpretation of degassed groundwater age tracer data.

Visual Contrast Enhancement Algorithm Based on Histogram Equalization

PubMed Central

Ting, Chih-Chung; Wu, Bing-Fei; Chung, Meng-Liang; Chiu, Chung-Cheng; Wu, Ya-Ching

2015-01-01

Image enhancement techniques primarily improve the contrast of an image to lend it a better appearance. One of the popular enhancement methods is histogram equalization (HE) because of its simplicity and effectiveness. However, it is rarely applied to consumer electronics products because it can cause excessive contrast enhancement and feature loss problems. These problems make the images processed by HE look unnatural and introduce unwanted artifacts in them. In this study, a visual contrast enhancement algorithm (VCEA) based on HE is proposed. VCEA considers the requirements of the human visual perception in order to address the drawbacks of HE. It effectively solves the excessive contrast enhancement problem by adjusting the spaces between two adjacent gray values of the HE histogram. In addition, VCEA reduces the effects of the feature loss problem by using the obtained spaces. Furthermore, VCEA enhances the detailed textures of an image to generate an enhanced image with better visual quality. Experimental results show that images obtained by applying VCEA have higher contrast and are more suited to human visual perception than those processed by HE and other HE-based methods. PMID:26184219

Hermite Functional Link Neural Network for Solving the Van der Pol-Duffing Oscillator Equation.

PubMed

Mall, Susmita; Chakraverty, S

2016-08-01

Hermite polynomial-based functional link artificial neural network (FLANN) is proposed here to solve the Van der Pol-Duffing oscillator equation. A single-layer hermite neural network (HeNN) model is used, where a hidden layer is replaced by expansion block of input pattern using Hermite orthogonal polynomials. A feedforward neural network model with the unsupervised error backpropagation principle is used for modifying the network parameters and minimizing the computed error function. The Van der Pol-Duffing and Duffing oscillator equations may not be solved exactly. Here, approximate solutions of these types of equations have been obtained by applying the HeNN model for the first time. Three mathematical example problems and two real-life application problems of Van der Pol-Duffing oscillator equation, extracting the features of early mechanical failure signal and weak signal detection problems, are solved using the proposed HeNN method. HeNN approximate solutions have been compared with results obtained by the well known Runge-Kutta method. Computed results are depicted in term of graphs. After training the HeNN model, we may use it as a black box to get numerical results at any arbitrary point in the domain. Thus, the proposed HeNN method is efficient. The results reveal that this method is reliable and can be applied to other nonlinear problems too.

Teaching Environmental History: Environmental Thinking and Practice in Europe, 1500 to the Present

ERIC Educational Resources Information Center

Schwartz, Robert M.

2006-01-01

In this article, the author describes the teaching methods he used in an environmental history course. He relates that the ecologist's web of life serves as his guiding principle for teaching in his course. From an imagined center of the web, he relates that he and his class move outward to explore two main areas of environmental history in the…

Penning ionization widths by Fano-algebraic diagrammatic construction method

NASA Astrophysics Data System (ADS)

Yun, Renjie; Narevicius, Edvardas; Averbukh, Vitali

2018-03-01

We present an ab initio theory and computational method for Penning ionization widths. Our method is based on the Fano theory of resonances, algebraic diagrammatic construction (ADC) scheme for many-electron systems, and Stieltjes imaging procedure. It includes an extension of the Fano-ADC scheme [V. Averbukh and L. S. Cederbaum, J. Chem. Phys. 123, 204107 (2005)] to triplet excited states. Penning ionization widths of various He*-H2 states are calculated as a function of the distance R between He* and H2. We analyze the asymptotic (large-R) dependences of the Penning widths in the region where the well-established electron transfer mechanism of the decay is suppressed by the multipole- and/or spin-forbidden energy transfer. The R-12 and R-8 power laws are derived for the asymptotes of the Penning widths of the singlet and triplet excited states of He*(1s2s1,3S), respectively. We show that the electron transfer mechanism dominates Penning ionization of He*(1s2s 3S)-H2 up until the He*-H2 separation is large enough for the radiative decay of He* to become the dominant channel. The same mechanism also dominates the ionization of He*(1s2s 1S)-H2 when R < 5 Å. We estimate that the regime of energy transfer in the He*-H2 Penning ionization cannot be reached by approaching zero collisional temperature. However, the multipole-forbidden energy transfer mechanism can become important for Penning ionization in doped helium droplets.

A comparison of exogenous and endogenous CEST MRI methods for evaluating in vivo pH.

PubMed

Lindeman, Leila R; Randtke, Edward A; High, Rachel A; Jones, Kyle M; Howison, Christine M; Pagel, Mark D

2018-05-01

Extracellular pH (pHe) is an important biomarker for cancer cell metabolism. Acido-chemical exchange saturation transfer (CEST) MRI uses the contrast agent iopamidol to create spatial maps of pHe. Measurements of amide proton transfer exchange rates (k ex ) from endogenous CEST MRI were compared to pHe measurements by exogenous acido-CEST MRI to determine whether endogenous k ex could be used as a proxy for pHe measurements. Spatial maps of pHe and k ex were obtained using exogenous acidoCEST MRI and an endogenous CEST MRI analyzed with the omega plot method, respectively, to evaluate mouse kidney, a flank tumor model, and a spontaneous lung tumor model. The pHe and k ex results were evaluated using pixelwise comparisons. The k ex values obtained from endogenous CEST measurements did not correlate with the pHe results from exogenous CEST measurements. The k ex measurements were limited to fewer pixels and had a limited dynamic range relative to pHe measurements. Measurements of k ex with endogenous CEST MRI cannot substitute for pHe measurements with acidoCEST MRI. Whereas endogenous CEST MRI may still have good utility for evaluating some specific pathologies, exogenous acido-CEST MRI is more appropriate when evaluating pathologies based on pHe values. Magn Reson Med 79:2766-2772, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

Research Methods in Healthcare Epidemiology and Antimicrobial Stewardship: Use of Administrative and Surveillance Databases.

PubMed

Drees, Marci; Gerber, Jeffrey S; Morgan, Daniel J; Lee, Grace M

2016-11-01

Administrative and surveillance data are used frequently in healthcare epidemiology and antimicrobial stewardship (HE&AS) research because of their wide availability and efficiency. However, data quality issues exist, requiring careful consideration and potential validation of data. This methods paper presents key considerations for using administrative and surveillance data in HE&AS, including types of data available and potential use, data limitations, and the importance of validation. After discussing these issues, we review examples of HE&AS research using administrative data with a focus on scenarios when their use may be advantageous. A checklist is provided to help aid study development in HE&AS using administrative data. Infect Control Hosp Epidemiol 2016;1-10.

Estimating roadside encroachment rates with the combined strengths of accident- and encroachment-based approaches

DOT National Transportation Integrated Search

2001-09-01

In two recent studies by Miaou, he proposed a method to estimate vehicle roadside encroachment rates using accident-based models. He further illustrated the use of this method to estimate roadside encroachment rates for rural two-lane undivided roads...

Extraction optimization and UHPLC method development for determination of the 20-hydroxyecdysone in Sida tuberculata leaves.

PubMed

da Rosa, Hemerson S; Koetz, Mariana; Santos, Marí Castro; Jandrey, Elisa Helena Farias; Folmer, Vanderlei; Henriques, Amélia Teresinha; Mendez, Andreas Sebastian Loureiro

2018-04-01

Sida tuberculata (ST) is a Malvaceae species widely distributed in Southern Brazil. In traditional medicine, ST has been employed as hypoglycemic, hypocholesterolemic, anti-inflammatory and antimicrobial. Additionally, this species is chemically characterized by flavonoids, alkaloids and phytoecdysteroids mainly. The present work aimed to optimize the extractive technique and to validate an UHPLC method for the determination of 20-hydroxyecdsone (20HE) in the ST leaves. Box-Behnken Design (BBD) was used in method optimization. The extractive methods tested were: static and dynamic maceration, ultrasound, ultra-turrax and reflux. In the Box-Behnken three parameters were evaluated in three levels (-1, 0, +1), particle size, time and plant:solvent ratio. In validation method, the parameters of selectivity, specificity, linearity, limits of detection and quantification (LOD, LOQ), precision, accuracy and robustness were evaluated. The results indicate static maceration as better technique to obtain 20HE peak area in ST extract. The optimal extraction from surface response methodology was achieved with the parameters granulometry of 710 nm, 9 days of maceration and plant:solvent ratio 1:54 (w/v). The UHPLC-PDA analytical developed method showed full viability of performance, proving to be selective, linear, precise, accurate and robust for 20HE detection in ST leaves. The average content of 20HE was 0.56% per dry extract. Thus, the optimization of extractive method in ST leaves increased the concentration of 20HE in crude extract, and a reliable method was successfully developed according to validation requirements and in agreement with current legislation. Copyright © 2018 Elsevier Inc. All rights reserved.

Methods for Measuring Lung Volumes: Is There a Better One?

PubMed

Tantucci, Claudio; Bottone, Damiano; Borghesi, Andrea; Guerini, Michele; Quadri, Federico; Pini, Laura

2016-01-01

Accurate measurement of lung volumes is of paramount importance to establish the presence of ventilatory defects and give insights for diagnostic and/or therapeutic purposes. It was the aim of this study to measure lung volumes in subjects with respiratory disorders and in normal controls by 3 different techniques (plethysmographic, dilutional and radiographic methods), in an attempt to clarify the role of each of them in performing such a task, without any presumptive 'a priori' superiority of one method above others. Patients andMethods: In different groups of subjects with obstructive and restrictive ventilatory defects and in a normal control group, total lung capacity, functional residual capacity (FRC) and residual volume were measured by body plethysmography, multi-breath helium (He) dilution and radiographic CT scan method with spirometric gating. The 3 methods gave comparable results in normal subjects and in patients with a restrictive defect. In patients with an obstructive defect, CT scan and plethysmography showed similar lung volumes, while on average significantly lower lung volumes were obtained with the He dilution technique. Taking into account that the He dilution technique does primarily measure FRC during tidal breathing, our data suggest that in some patients with an obstructive defect, a number of small airways can be functionally closed at end-expiratory lung volume, preventing He to reach the lung regions subserved by these airways. In all circumstances, both CT scan with spirometric gating and plethysmographic methods provide similar values of lung volumes. In contrast, the He dilution method can measure lower lung volumes in some patients with chronic airflow obstruction. © 2016 S. Karger AG, Basel.

An ab initio-based Er–He interatomic potential in hcp Er

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

Yang, Li; ye, Yeting; Fan, K. M.

2014-09-01

We have developed an empirical erbium-helium (Er-He) potential by fitting to the results calculated from ab initio method. Based on the electronic hybridization between Er and He atoms, an s-band model, along with a repulsive pair potential, has been derived to describe the Er-He interaction. The atomic configurations and the formation energies of single He defects, small He interstitial clusters (Hen) and He-vacancy (HenV ) clusters obtained by ab initio calculations are used as the fitting database. The binding energies and relative stabilities of the HnVm clusters are studied by the present potential and compared with the ab initio calculations.more » The Er-He potential is also applied to study the migration of He in hcp-Er at different temperatures, and He clustering is found to occur at 600 K in hcp Er crystal, which may be due to the anisotropic migration behavior of He interstitials.« less

Measurement of fast minority /sub 3/He/sup + +/ energy distribution during ICRF heating

DOEpatents

Post, D.E. Jr.; Grisham, L.R.; Medley, S.S.

A method and means for measuring the fast /sub 3/He/sup + +/ distribution during /sub 3/He/sup + +/ minority Ion Cyclotron Resonance Frequency (ICRF) heating is disclosed. The present invention involves the use of 10 to 100 keV beams of neutral helium atoms to neutralize the fast /sub 3/He/sup + +/ ions in a heated plasma by double charge exchange (/sub 3/He/sup + +/ + /sub 4/He/sup 0/ ..-->.. /sub 3/He/sup 0/ + /sub 4/He/sup + +/). The neutralized fast /sub 3/He/sup 0/ atoms then escape from the hot plasma confined by a magnetic field and are detected by conventional neutral particle analyzing means. This technique permits the effectiveness of the coupling of the ion cyclotron waves to the /sub 3/He/sup + +/ minority ions to be accurately measured. The present invention is particularly adapted for use in evaluating the effectiveness of the intermediate coupling between the RF heating and the /sub 3/He/sup + +/ in an energetic toroidal plasma.

Quantum mechanical characterization of the He4ICl weakly bound complex.

PubMed

Valdés, Álvaro; Prosmiti, Rita

2013-08-15

Vibrational calculations are performed for the 12-dimensional He4ICl van der Waals complex using the multiconfiguration time-dependent Hartree (MCTDH) method. The potential energy surface of the cluster is represented as a sum of the triatomic He-ICl ab initio parametrized terms plus the He-He interactions. The topology of the potential presents higher anisotropy compared to the one with a homonuclear dopant, and this is clearly reflected in the structure and energetics of the low-lying conformers of the system. In order to take advantage of the MCTDH method, natural potential fits are employed for the potential energy operator, and also, a mode combination scheme is introduced in order to speed up the computations. Zero-point energy, binding energies, and vibrationally averaged structures of different isomers of the He4ICl cluster are obtained. The present results predict that the (3,1,0) structure, involving three He atoms in the near T-shaped and one He atom in the linear configurations, to be the most stable one in accord with recent experimental findings. Comparisons with previous theoretical and experimental data are presented, and the stability of the high-order conformers is discussed in connection with the multiple minima (global and local) of the underlying potential surface.

Simultaneous detection of five different 2-hydroxyethyl-DNA adducts formed by ethylene oxide exposure, using a high-performance liquid chromatography/electrospray ionisation tandem mass spectrometry assay.

PubMed

Tompkins, Elaine M; Jones, Donald J L; Lamb, John H; Marsden, Debbie A; Farmer, Peter B; Brown, Karen

2008-01-01

A method has been developed for the simultaneous detection and quantitation of five different 2-hydroxyethyl-DNA (HE-DNA) adducts that could be formed as a result of exposure to ethylene oxide (EO). In addition to the major N7-HE-guanine (N7-HEG) adducts this assay can also measure the less prevalent but potentially more biologically significant N1-HE-2'-deoxyadenosine (N1-HEdA), O(6)-HE-2'-deoxyguanosine (O(6)-HEdG), N(6)-HE-2'-deoxyadenosine (N(6)-HEdA) and N3-HE-2'-deoxyuridine adducts (N3-HEdU). The method involves the isolation of HE adducts from the unmodified nucleosides by either neutral thermal hydrolysis or enzymatic digestion, followed by high-performance liquid chromatographic (HPLC) purification, before detection and quantification by liquid chromatography tandem mass spectrometry (LC/MS/MS) using selective reaction monitoring (SRM). The limits of detection were in the range 0.5-25 fmol for each individual adduct, making this one of the most sensitive assays available for the detection of N7-HEG. To illustrate the possible applications of the assay, it has been employed in the measurement of endogenous/background and EO-induced HE adducts in a variety of DNA samples.

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

Aciego, S.M.; Jourdan, F.; DePaolo, D.J.

Late Quaternary, post-shield lavas from the Mauna Kea and Kohala volcanoes on the Big Island of Hawaii have been dated using the {sup 40}Ar/{sup 39}Ar and U-Th/He methods. The objective of the study is to compare the recently demonstrated U-Th/He age method, which uses basaltic olivine phenocrysts, with {sup 40}Ar/{sup 39}Ar ages measured on groundmass from the same samples. As a corollary, the age data also increase the precision of the chronology of volcanism on the Big Island. For the U-Th/He ages, U, Th and He concentrations and isotopes were measured to account for U-series disequilibrium and initial He. Singlemore » analyses U-Th/He ages for Hamakua lavas from Mauna Kea are 87 {+-} 40 ka to 119 {+-} 23 ka (2{sigma} uncertainties), which are in general equal to or younger than {sup 40}Ar/{sup 39}Ar ages. Basalt from the Polulu sequence on Kohala gives a U-Th/He age of 354 {+-} 54 ka and a {sup 40}Ar/{sup 39}Ar age of 450 {+-} 40 ka. All of the U-Th/He ages, and all but one spurious {sup 40}Ar/{sup 39}Ar ages conform to the previously proposed stratigraphy and published {sup 14}C and K-Ar ages. The ages also compare favorably to U-Th whole rock-olivine ages calculated from {sup 238}U - {sup 230}Th disequilibria. The U-Th/He and {sup 40}Ar/{sup 39}Ar results agree best where there is a relatively large amount of radiogenic {sup 40}Ar (>10%), and where the {sup 40}Ar/{sup 36}Ar intercept calculated from the Ar isochron diagram is close to the atmospheric value. In two cases, it is not clear why U-Th/He and {sup 40}Ar/{sup 39}Ar ages do not agree within uncertainty. U-Th/He and {sup 40}Ar/{sup 39}Ar results diverge the most on a low-K transitional tholeiitic basalt with abundant olivine. For the most alkalic basalts with negligible olivine phenocrysts, U-Th/He ages were unattainable while {sup 40}Ar/{sup 39}Ar results provide good precision even on ages as low as 19 {+-} 4 ka. Hence, the strengths and weaknesses of the U-Th/He and {sup 40}Ar/{sup 39}Ar methods are complimentary for basalts with ages of order 100-500 ka.« less

Characteristics of students in comparative problem solving

NASA Astrophysics Data System (ADS)

Irfan, M.; Sudirman; Rahardi, R.

2018-01-01

Often teachers provided examples and exercised to students with regard to comparative problems consisting of one quantity. In this study, the researchers gave the problem of comparison with the two quantities mixed. It was necessary to have a good understanding to solve this problem. This study aimed to determine whether students understand the comparison in depth and be able to solve the problem of non-routine comparison. This study used qualitative explorative methods, with researchers conducting in-depth interviews on subjects to explore the thinking process when solving comparative problems. The subject of this study was three students selected by purposive sampling of 120 students. From this research, researchers found there were three subjects with different characteristics, namely: subject 1, he did the first and second questions with methods of elimination and substitution (non-comparison); subject 2, he did the first question with the concept of comparison although the answer was wrong, and did the second question with the method of elimination and substitution (non-comparison); and subject 3, he did both questions with the concept of comparison. In the first question, he did wrong because he was unable to understand the problem, while on the second he did correctly. From the characteristics of the answers, the researchers divided into 3 groups based on thinking process, namely: blind-proportion, partial-proportion, and proportion thinking.

The combined positive impact of Lean methodology and Ventana Symphony autostainer on histology lab workflow

PubMed Central

2010-01-01

Background Histologic samples all funnel through the H&E microtomy staining area. Here manual processes intersect with semi-automated processes creating a bottleneck. We compare alternate work processes in anatomic pathology primarily in the H&E staining work cell. Methods We established a baseline measure of H&E process impact on personnel, information management and sample flow from historical workload and production data and direct observation. We compared this to performance after implementing initial Lean process modifications, including workstation reorganization, equipment relocation and workflow levelling, and the Ventana Symphony stainer to assess the impact on productivity in the H&E staining work cell. Results Average time from gross station to assembled case decreased by 2.9 hours (12%). Total process turnaround time (TAT) exclusive of processor schedule changes decreased 48 minutes/case (4%). Mean quarterly productivity increased 8.5% with the new methods. Process redesign reduced the number of manual steps from 219 to 182, a 17% reduction. Specimen travel distance was reduced from 773 ft/case to 395 ft/case (49%) overall, and from 92 to 53 ft/case in the H&E cell (42% improvement). Conclusions Implementation of Lean methods in the H&E work cell of histology can result in improved productivity, improved through-put and case availability parameters including TAT. PMID:20181123

Suicide, Immortality, and the Method of Embarrassments

ERIC Educational Resources Information Center

Bakan, David

1976-01-01

This paper, presented at Self-Destruction and Self-Creation, at Duquesne University (April, 1969) explains that the suicide, reacting to his experience of "being in question" (Heidegger), kills himself to arrogate death to his will. He allows the possibility that if he wished it, he could live forever and usurp death. (Author)

Computational Methods for Probabilistic Target Tracking Problems

DTIC Science & Technology

2007-09-01

he is working with the Aegis Ballistic Missile Defense System (ABMD) in the Command and Decision (C&D) section. He has recently been selected from a...employed by Progress Energy as an Auxillary Operator at the Brunswick Nuclear Plant, in Southport NC. He is studying to qualify as an NRC licensed nuclear

Big bang nucleosynthesis revisited via Trojan Horse method measurements

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

Pizzone, R. G.; Spartá, R.; Spitaleri, C.

Nuclear reaction rates are among the most important input for understanding primordial nucleosynthesis and, therefore, for a quantitative description of the early universe. An up-to-date compilation of direct cross-sections of {sup 2}H(d, p){sup 3}H, {sup 2}H(d, n){sup 3}He, {sup 7}Li(p, α){sup 4}He, and {sup 3}He(d, p){sup 4}He reactions is given. These are among the most uncertain cross-sections used and input for big bang nucleosynthesis calculations. Their measurements through the Trojan Horse method are also reviewed and compared with direct data. The reaction rates and the corresponding recommended errors in this work were used as input for primordial nucleosynthesis calculations tomore » evaluate their impact on the {sup 2}H, {sup 3,4}He, and {sup 7}Li primordial abundances, which are then compared with observations.« less

A "Large and Graceful Sinuosity": John Herschel's Graphical Method

NASA Astrophysics Data System (ADS)

Hankins, Thomas L.

2006-12-01

In 1833 John Herschel published a graphical method for determining the orbits of double stars. He argued that this method, which depended on human judgment rather than mathematical analysis, gave better results than computation, given the uncertainty in the data. Herschel found that astronomy and terrestrial physics were especially suitable for graphical treatment, and he expected that graphs would soon become important in all areas of science. He argued with William Whewell and James D. Forbes over the process of induction, over the application of probability, and over the moral content of science. Graphs entered into all these debates, but because they constituted a method, not a metaphysics, they were acceptable to most practicing scientists and became increasingly popular throughout the nineteenth century.

Solution of Fifth-order Korteweg and de Vries Equation by Homotopy perturbation Transform Method using He's Polynomial

NASA Astrophysics Data System (ADS)

Sharma, Dinkar; Singh, Prince; Chauhan, Shubha

2017-06-01

In this paper, a combined form of the Laplace transform method with the homotopy perturbation method is applied to solve nonlinear fifth order Korteweg de Vries (KdV) equations. The method is known as homotopy perturbation transform method (HPTM). The nonlinear terms can be easily handled by the use of He's polynomials. Two test examples are considered to illustrate the present scheme. Further the results are compared with Homotopy perturbation method (HPM).

Advances in Laser Microprobe (U-Th)/He Geochronology

NASA Astrophysics Data System (ADS)

van Soest, M. C.; Monteleone, B. D.; Boyce, J. W.; Hodges, K. V.

2008-12-01

The development of the laser microprobe (U-Th)/He dating method has the potential to overcome many of the limitations that affect conventional (U-Th)/He geochronology. Conventional single- or multi-crystal (U- Th)/He geochronology requires the use of pristine, inclusion-free, euhedral crystals. Furthermore, the ages that are obtained require corrections for the effects of zoning and alpha ejection based on an ensemble of assumptions before interpretation of their geological relevance is possible. With the utilization of microbeam techniques many of the limitations of conventional (U-Th)/He geochronology can either be eliminated by careful spot selection or accounted for by detailed depth profiling analyses of He, U and Th on the same crystal. Combined He, Th, and U depth profiling on the same crystal potentially even offers the ability to extract thermal histories from the analyzed grains. Boyce et al. (2006) first demonstrated the laser microprobe (U-Th)/He dating technique by successfully dating monazite crystals using UV laser ablation to liberate He and determined U and Th concentrations using a Cameca SX-Ultrachron microprobe. At Arizona State University, further development of the microprobe (U-Th)/He dating technique continues using an ArF Excimer laser connected to a GVI Helix Split Flight Tube noble gas mass spectrometer for He analysis and SIMS techniques for U and Th. The Durango apatite age standard has been successfully dated at 30.7 +/- 1.7 Ma (2SD). Work on dating zircons by laser ablation is currently underway, with initial results from Sri Lanka zircon at 437 +/- 14 Ma (2SD) confirmed by conventional (U-Th)/He analysis and in agreement with the published (U-Th)/He age of 443 +/- 9 Ma (2SD) for zircons from this region in Sri Lanka (Nasdala et al., 2004). The results presented here demonstrate the laser microprobe (U-Th)/He method as a powerful tool that allows application of (U- Th)/He dating to areas of research such as detrital apatite and zircon dating, where conventional (U-Th)/He geochronology has limited applicability. Boyce et al. (2006) GCA 70 (3031-3039), Nasdala et al. (2004) Am. Min. 89 (219-231)

Enhanced End-Contacts by Helium Ion Bombardment to Improve Graphene-Metal Contacts

PubMed Central

Jia, Kunpeng; Su, Yajuan; Zhan, Jun; Shahzad, Kashif; Zhu, Huilong; Zhao, Chao; Luo, Jun

2016-01-01

Low contact resistance between graphene and metals is of paramount importance to fabricate high performance graphene-based devices. In this paper, the impact of both defects induced by helium ion (He+) bombardment and annealing on the contact resistance between graphene and various metals (Ag, Pd, and Pt) were systematically explored. It is found that the contact resistances between all metals and graphene are remarkably reduced after annealing, indicating that not only chemically adsorbed metal (Pd) but also physically adsorbed metals (Ag and Pt) readily form end-contacts at intrinsic defect locations in graphene. In order to further improve the contact properties between Ag, Pd, and Pt metals and graphene, a novel method in which self-aligned He+ bombardment to induce exotic defects in graphene and subsequent thermal annealing to form end-contacts was proposed. By using this method, the contact resistance is reduced significantly by 15.1% and 40.1% for Ag/graphene and Pd/graphene contacts with He+ bombardment compared to their counterparts without He+ bombardment. For the Pt/graphene contact, the contact resistance is, however, not reduced as anticipated with He+ bombardment and this might be ascribed to either inappropriate He+ bombardment dose, or inapplicable method of He+ bombardment in reducing contact resistance for Pt/graphene contact. The joint efforts of as-formed end-contacts and excess created defects in graphene are discussed as the cause responsible for the reduction of contact resistance. PMID:28335286

Why Did Socrates Deny That He Was a Teacher? Locating Socrates among the New Educators and the Traditional Education in Plato's "Apology of Socrates"

ERIC Educational Resources Information Center

Mintz, Avi I.

2014-01-01

Plato's "Apology of Socrates" contains a spirited account of Socrates' relationship with the city of Athens and its citizens. As Socrates stands on trial for corrupting the youth, surprisingly, he does not defend the substance and the methods of his teaching. Instead, he simply denies that he is a teacher. Many scholars have…

Ionization of polarized {sup 3}He{sup +} ions in EBIS trap with slanted electrostatic mirror

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

Pikin, A.; Zelenski, A.; Kponou, A.

2008-02-06

Methods of producing the nuclear polarized {sup 3}He{sup +} ions and their ionization to {sup 3}He{sup ++} in ion trap of the electron Beam Ion Source (EBIS) are discussed. Computer simulations show that injection and accumulation of {sup 3}He{sup +} ions in the EBIS trap with slanted electrostatic mirror can be very effective for injection times longer than the ion traversal time through the trap.

People and Planned Change/Manipulation versus Modification.

ERIC Educational Resources Information Center

West, Bob; Dormant, Diane

1979-01-01

Presents excerpts from a workshop (on change agentry) participant's letter in which he disagrees with equating "covert,""overt," and "infiltrate" with the unethical manipulation of people. He defines covert and overt methods of influencing decision makers and identifies methods that could be borrowed from other areas to broaden options. (Author/JD)

Laser ablation U-Th-Sm/He dating of detrital apatite

NASA Astrophysics Data System (ADS)

Guest, B.; Pickering, J. E.; Matthews, W.; Hamilton, B.; Sykes, C.

2016-12-01

Detrital apatite U-Th-Sm/He thermochronology has the potential to be a powerful tool for conducting basin thermal history analyses as well as complementing the well-established detrital zircon U-Pb approach in source to sink studies. A critical roadblock that prevents the routine application of detrital apatite U-Th-Sm/He thermochronology to solving geological problems is the costly and difficult whole grain approach that is generally used to obtain apatite U-Th-Sm/He data. We present a new analytical method for laser ablation thermochronology on apatite. Samples are ablated using a Resonetics™ 193 nm excimer laser and liberated 4He is measured using an ASI (Australian Scientific Instruments) Alphachron™ quadrupole mass spectrometer system; collectively known as the Resochron™. The ablated sites are imaged using a Zygo ZescopeTM optical profilometer and ablated pit volume measured using PitVol, a custom MatLabTM algorithm. The accuracy and precision of the method presented here was confirmed using well-characterized Durango apatite and Fish Canyon Tuff (FCT) apatite reference materials, with Durango apatite used as a primary reference and FCT apatite used as a secondary reference. The weighted average of our laser ablation Durango ages (30.5±0.35 Ma) compare well with ages obtained using conventional whole grain degassing and dissolution U-Th-Sm/He methods (32.56±0.43 Ma) (Jonckheere et.al., 1 993; Farley, 2000; McDowell et.al., 2005) for chips of the same Durango crystal. These Durango ages were used to produce a K-value to correct the secondary references and unknown samples. After correction, FCT apatite has a weighted average age of 28.37 ± 0.96 Ma, which agrees well with published ages. As a further test of this new method we have conducted a case study on a set of samples from the British Mountains of the Yukon Territory in NW Canada. Sandstone samples collected across the British Mountains were analyzed using conventional U-Th-Sm/He whole grain methods and then reanalyzed using our new Laser ablation approach. The laser ablation results are consistent with those obtained using conventional methods, confirming that apatite laser ablation U-Th-Sm/He thermochronology is a viable alternative for collecting large low temperature thermochronology data sets from detrital samples.

Vittorio Marchi, MD (1851-1908): an unsung pioneer of neuroscience.

PubMed

Talamonti, Giuseppe; D'Aliberti, Giuseppe; Debernardi, Alberto; Innocenti, Gloria

2013-11-01

Vittorio Marchi was an Italian neuroscientist who lived during the second half of the 19th century. He is generally remembered for developing a novel staining method to trace the degeneration of nervous fibers in lesions of the central nervous system. This osmium-based method was used worldwide for approximately a century and continues to be cited in modern textbooks. Despite several important original scientific contributions, Marchi was never awarded a university chair. Discouraged, he left to practice neurology in a rural area but continued to write outstanding articles, and in 1897, he became a pioneer of meningioma surgery. Today, he is remembered only in specialized contexts. We hope this article can provide the recognition that Marchi deserves.

Molecular dynamics simulations of the diffusion and coalescence of helium in tungsten

NASA Astrophysics Data System (ADS)

Zhou, Y. L.; Wang, J.; Hou, Q.; Deng, A. H.

2014-03-01

Molecular dynamics (MD) simulations are performed on the diffusion and coalescence of helium in tungsten. A new method for determining the effective capture radii (ECRs) and the dissociation energies of helium-related defects is proposed in this work. It is observed that the ECR of an interstitial helium atom trapping helium interstitials (denoted as He-Hen, n = 1-3) decreases with increasing temperature, except for He-He2 at T < 400 K. The traditional view that the ECR is approximately equal to the lattice constant, which has been widely used in kinetic Monte Carlo (KMC) and rate theory (RT) models, is only valid in some cases. However, the ECR between an interstitial helium atom and a substitutional helium atom (denoted as He-HeV) always approximates the third nearest-neighbor tetrahedral positions of the HeV. The diffusion coefficients Dn for helium clusters are also investigated. He2 migrates more quickly than a single He atom does at T < 400 K, whereas the diffusion path of He2 changes at higher temperatures. Another counterintuitive observation is that D5 > D3 > D4 at T < 500 K, which can be attributed to the disordered structure of He5. The Arrhenius relation describes the diffusion of Hen well in the temperature range from 300 K to 550 K, whereas the diffusion is not a standard thermally activated process at higher temperatures. Taken together, these results help elucidate the initial stage of helium bubble formation in tungsten as well as the requirements of long-term evolution methods such as KMC or RT models.

Development of Decision Making Algorithm for Control of Sea Cargo Containers by ``TAGGED'' Neutron Method

NASA Astrophysics Data System (ADS)

Anan'ev, A. A.; Belichenko, S. G.; Bogolyubov, E. P.; Bochkarev, O. V.; Petrov, E. V.; Polishchuk, A. M.; Udaltsov, A. Yu.

2009-12-01

Nowadays in Russia and abroad there are several groups of scientists, engaged in development of systems based on "tagged" neutron method (API method) and intended for detection of dangerous materials, including high explosives (HE). Particular attention is paid to possibility of detection of dangerous objects inside a sea cargo container. Energy gamma-spectrum, registered from object under inspection is used for determination of oxygen/carbon and nitrogen/carbon chemical ratios, according to which dangerous object is distinguished from not dangerous one. Material of filled container, however, gives rise to additional effects of rescattering and moderation of 14 MeV primary neutrons of generator, attenuation of secondary gamma-radiation from reactions of inelastic neutron scattering on objects under inspection. These effects lead to distortion of energy gamma-response from examined object and therefore prevent correct recognition of chemical ratios. These difficulties are taken into account in analytical method, presented in the paper. Method has been validated against experimental data, obtained by the system for HE detection in sea cargo, based on API method and developed in VNIIA. Influence of shielding materials on results of HE detection and identification is considered. Wood and iron were used as shielding materials. Results of method application for analysis of experimental data on HE simulator measurement (tetryl, trotyl, hexogen) are presented.

Multicellular tumor spheroids as an in vivo-like tumor model for three-dimensional imaging of chemotherapeutic and nano material cellular penetration.

PubMed

Ma, Hui-li; Jiang, Qiao; Han, Siyuan; Wu, Yan; Cui Tomshine, Jin; Wang, Dongliang; Gan, Yaling; Zou, Guozhang; Liang, Xing-Jie

2012-01-01

We present a flexible and highly reproducible method using three-dimensional (3D) multicellular tumor spheroids to quantify chemotherapeutic and nanoparticle penetration properties in vitro. We generated HeLa cell-derived spheroids using the liquid overlay method. To properly characterize HeLa spheroids, scanning electron microscopy, transmission electron microscopy, and multiphoton microscopy were used to obtain high-resolution 3D images of HeLa spheroids. Next, pairing high-resolution optical characterization techniques with flow cytometry, we quantitatively compared the penetration of doxorubicin, quantum dots, and synthetic micelles into 3D HeLa spheroid versus HeLa cells grown in a traditional two-dimensional culturing system. Our data revealed that 3D cultured HeLa cells acquired several clinically relevant morphologic and cellular characteristics (such as resistance to chemotherapeutics) often found in human solid tumors. These characteristic, however, could not be captured using conventional two-dimensional cell culture techniques. This study demonstrated the remarkable versatility of HeLa spheroid 3D imaging. In addition, our results revealed the capability of HeLa spheroids to function as a screening tool for nanoparticles or synthetic micelles that, due to their inherent size, charge, and hydrophobicity, can penetrate into solid tumors and act as delivery vehicles for chemotherapeutics. The development of this image-based, reproducible, and quantifiable in vitro HeLa spheroid screening tool will greatly aid future exploration of chemotherapeutics and nanoparticle delivery into solid tumors.

IN MEMORIAM In memoriam of Vladilen Letokhov (1939-2009)

NASA Astrophysics Data System (ADS)

Balykin, Victor

2011-01-01

On 21 March 2009 Professor Vladilen Letokhov passed away in Troitsk near Moscow. Letokhov was an outstanding scientist in laser physics and laser spectroscopy. He was born on 10 November 1939 in the small Siberian town of Taishet, not far from Lake Baikal. After graduating from the Moscow Institute of Physics and Technology (MIPT) in 1963, he attended the Physical Institute of the USSR Academy of Sciences. He did his postgraduate studies under the supervision of Nobel laureate Nicolay Basov. In 1969 he defended his PhD thesis on the theory of laser pulse generation and amplification, and a year later he received a second doctor of science degree in quantum radiophysics. In 1970 Vladilen went to the new Institute of Spectroscopy at the USSR Academy of Sciences in Troitsk. He became the deputy director for research and organized the department of laser spectroscopy, which he headed until his last days. Letokhov was also a faculty member at the MIPT, where he served as a professor of physics from 1972 to his death and as head of the chair of quantum optics from 1986 to 1998. Letokhov's scientific interests included various areas of laser physics, spectroscopy, chemistry, and biomedicine. His most important contributions, however, were in the field of laser spectroscopy. He was the first to realize selective detection of atoms and molecules by multiphoton resonant ionization, which made it possible to develop methods of ultrasensitive analysis. To him belonged the discovery of nonresonance feedback in random lasers. Letokhov was also among the first to achieve laser spectroscopy with sub-wavelength spatial resolution. With his collaborators, he suggested and developed methods of laser control of atomic motion, resulting in the creation of atom traps based on gradient forces. His group carried out the first experiments on cooling, collimation, and reflection of atom beams by laser radiation. Letokhov made decisive contributions to the development of methods of selective laser chemistry, including isotope-selective multiphoton dissociation of molecules by IR laser radiation and vibrationally mediated photochemistry. He developed several effective schemes of laser isotope separation and the first commercial plant for laser isotope separation was created in 1998. Letokhov and his coworkers performed groundbreaking experiments in laser mass spectroscopy of organic molecules, and they also developed methods of picosecond and femtosecond nonlinear laser spectroscopy for the investigation and control of ultrafast processes in condensed media. In recent years Letokhov was engaged in research on laser effects in stellar atmospheres, which he predicted at the beginning of his career. The scientific results obtained by Letokhov and his coworkers were widely recognized. For his efforts, he was awarded the 1978 Lenin Prize, the 1998 Quantum Electronics Prize of the European Physical Society, the 2001 Rozhdestvensky Prize of the Russian Academy of Sciences, and the 2002 State Prize of the Russian Federation. For many years Letokhov was involved in the publishing of international scientific journals. Among the publications he edited were Laser Science and Technology and the Journal of Nonlinear Optics. He also served on the editorial boards of the Journal of Experimental and Theoretical Physics, Chemical Physics Letters, Applied Physics B, and others. He was an author on more than 850 research papers, including 15 monographs. Letokhov was a self-made man who, beginning in his school years, persistently used every possibility to broaden his educational and cultural knowledge. Although he was devoted to science and gave it considerable time, he also was deeply interested in literature, music, art, and history. He was an exceptionally interesting conversationalist and a man of great erudition. He is sadly missed by his many colleagues and friends. Letokhov photo

The early evolution of Jean Piaget's clinical method.

PubMed

Mayer, Susan Jean

2005-11-01

This article analyzes the early evolution of Jean Piaget's renowned "clinical method" in order to investigate the method's strikingly original and generative character. Throughout his 1st decade in the field, Piaget frequently discussed and justified the many different approaches to data collection he used. Analysis of his methodological progression during this period reveals that Piaget's determination to access the genuine convictions of children eventually led him to combine 3 distinct traditions in which he had been trained-naturalistic observation, psychometrics, and the psychiatric clinical examination. It was in this amalgam, first evident in his 4th text, that Piaget discovered the clinical dynamic that would drive the classic experiments for which he is most well known.

Generalized Jastrow variational method for liquid3He-4He mixtures at T=0 K

NASA Astrophysics Data System (ADS)

Mirabbaszadeh, K.

1989-07-01

The ground state energy of a dilute solution of mass-3 fermions in liquid4He is analyzed by a variational procedure based on the Jastrow many body theory. The antisymmetry of the wave function for fermions is incorporated following the procedure given by Lado, Inguva, and Smith. A set of coupled integrodifferential equations is solved in the hypernetted chain approximation yielding expressions for the binding energy of3He-4He mixtures; the radial distribution function is given together with the total energy for various values of density and the interparticle separation r s.

Subnetwork mining on functional connectivity network for classification of minimal hepatic encephalopathy.

PubMed

Zhang, Daoqiang; Tu, Liyang; Zhang, Long-Jiang; Jie, Biao; Lu, Guang-Ming

2018-06-01

Hepatic encephalopathy (HE), as a complication of cirrhosis, is a serious brain disease, which may lead to death. Accurate diagnosis of HE and its intermediate stage, i.e., minimal HE (MHE), is very important for possibly early diagnosis and treatment. Brain connectivity network, as a simple representation of brain interaction, has been widely used for the brain disease (e.g., HE and MHE) analysis. However, those studies mainly focus on finding disease-related abnormal connectivity between brain regions, although a large number of studies have indicated that some brain diseases are usually related to local structure of brain connectivity network (i.e., subnetwork), rather than solely on some single brain regions or connectivities. Also, mining such disease-related subnetwork is a challenging task because of the complexity of brain network. To address this problem, we proposed a novel frequent-subnetwork-based method to mine disease-related subnetworks for MHE classification. Specifically, we first mine frequent subnetworks from both groups, i.e., MHE patients and non-HE (NHE) patients, respectively. Then we used the graph-kernel based method to select the most discriminative subnetworks for subsequent classification. We evaluate our proposed method on a MHE dataset with 77 cirrhosis patients, including 38 MHE patients and 39 NHE patients. The results demonstrate that our proposed method can not only obtain the improved classification performance in comparison with state-of-the-art network-based methods, but also identify disease-related subnetworks which can help us better understand the pathology of the brain diseases.

[Eustachy Gryszkiewicz-Trochimowski (1888-1971) chemist].

PubMed

Morawski, Bogdan

2011-01-01

Eustachy Gryszkiewicz-Trochimowski was born on April 17, 1888, in Kowle on Volhynia. Having graduated from classical grammar-school in Humań, he began his studies in the Faculty of Mathematics and Natural Science in the University of St. Wlodzimierz in Kiev. His scientific interests in chemistry appeared already during university studies. This fact attracted his teacher's attention--a distinguished organic chemist--professor S. N. Reformatski (1860-1938). The first works he published in the years 1908-1909. In 1910 professor Reformatski appointed him to a post of assistant in laboratory of organic chemistry within Higher Women Classes. In 1913 Gryszkiewicz-Trochimowski was employed as an assistant professor, and as a lecturer in chemistry was appointed to a post of professor in Higher Institute of Trade. After professor Reformatski had retired in 1917, Gryszkiewicz-Trochimowski was appointed to a professorship and took over a chair in Organic Chemistry Department. In 1925, having moved to Poland, he resigned from academic career. Having returned to Poland, he began to work in Research Institute of Chemical Weapons, in which took up systematic and extensive research works over arsenoorganic compounds, and combinations including fluorine. He worked out an original method of producing an unavailable compound of oxym of phosgene, which later was widely used, and also beyond the army. The combination was available just by dint of the method that was introduced by Gryszkiewicz-Trochimowski. In Poland the method of producing oxym of phosgene was concealed, and the compound was produced under a secret name TSD together with sulphuric yperite. Moreover, Gryszkiewicz-Trochimowski took up intensive scientific researches on synthesis of halogen derivatives of aliphatic, and aliphatic and aromatic ketones. In the second half of the 1930s, together with the closest co-workers--doctor Adam Sporzyński and Lieutenant MA Jakub Wnuk--he worked out a new method of synthesis of organic-fluoric combinations. The method was kept in the strictest secrecy and was revealed in 1942 to the English by doctor Sporzyński while visiting Great Britain. The results of the Warsaw research works were laid before professor of the University of Cambridge--H. McCombiem, who presented them as his own discovery, and who took a patent for the method. While doing research works in the Institute, Eustachy Gryszkiewicz-Trochimowski with an approval of army administration since January, 1929, started to work in Industry and Trade Establishments of Chemistry--L. Spiess & Son. Co-operating with the company for 10 years, he elaborated and applied the modified methods of producing many synthetic remedies, and worked out a program of establishment's production that could easily conform with the modern chemical and pharmaceutical factory. The program in the post-war period was continued almost for two decades. Gryszkiewicz-Trochimowski was the only chemist in Poland, who did his research works over synthetic healers. In the period of occupation he worked for a while in the company "Spiess". In 1943 he was informed of the murder in Katyń of his co-worker--captain doctor Wnuk. A perspective of annextion of Polish territories by the Soviets was for him a serious threat and thus he started making attempts at leaving for the west. He left the country under unknown circumstances and found himself in France. After the end of World War II he published a great many of his works that earlier had been kept in secret. In France he was employed in the military scientific and research institution--Centre d'Etudes du Buchet--and was engaged in works over a French program of defence. Having lived to be seventy nine, died on February 25, 1971, in Brazil.

Ground-state energy of HeH+

NASA Astrophysics Data System (ADS)

Zhou, Bing-Lu; Zhu, Jiong-Ming; Yan, Zong-Chao

2006-06-01

The nonrelativistic ground-state energy of He4H+ is calculated using a variational method in Hylleraas coordinates. Convergence to a few parts in 1010 is achieved, which improves the best previous result of Pavanello [J. Chem. Phys. 123, 104306 (2005)]. Expectation values of the interparticle distances are evaluated. Similar results for He3H+ are also presented.

The Method of Jean Louis Nicolet

ERIC Educational Resources Information Center

Gattegno, Caleb

2007-01-01

Jean Louis Nicolet is a Swiss teacher of mathematics who found his subject so fascinating that he was puzzled as to why so many pupils could not share this enjoyment in their studies. He came to a conclusion which is now supported by the results of psychological research into the learning process: he suggested that the mind does not spontaneously…

[Professor HE Tianyou's clinical experience of acupuncture and medicine on intractable facial paralysis].

PubMed

Yan, Fenghua; Yao, Xuhong; Yan, Xingke; Zhang, Yongkui; Jing, Xiaohui; He, Tianyou

2015-02-01

Professor HE Tianyou's unique understanding and treatment characteristics for intractahle facial paralysis are introduced. In clinical practice professor HE highly values acupoint selection and manipulation application, and integrates Chinese and western medicine to flexibly choose acupoints and formulate prescriptions according to syndrome differentiation and location differentiation, besides, he creates several specialized manipulation methods including "tug-of war opposite acupuncture method" and "tractive flash cupping". Based on strengthening body and dredging collaterals. more attention is given on stimulation to local paralyzed facial nerves; meanwhile acupuncture and medication are combined to improve clinical efficacy. During the treatment, the important role of psychological counseling on patient's anxiety is emphasized, and comprehensive treatment is given physically and psychologically in order to achieve the purpose of total rehabilitation.

Optically polarized 3He

PubMed Central

Gentile, T. R.; Nacher, P. J.; Saam, B.; Walker, T. G.

2018-01-01

This article reviews the physics and technology of producing large quantities of highly spin-polarized 3He nuclei using spin-exchange (SEOP) and metastability-exchange (MEOP) optical pumping. Both technical developments and deeper understanding of the physical processes involved have led to substantial improvements in the capabilities of both methods. For SEOP, the use of spectrally narrowed lasers and K-Rb mixtures has substantially increased the achievable polarization and polarizing rate. For MEOP nearly lossless compression allows for rapid production of polarized 3He and operation in high magnetic fields has likewise significantly increased the pressure at which this method can be performed, and revealed new phenomena. Both methods have benefitted from development of storage methods that allow for spin-relaxation times of hundreds of hours, and specialized precision methods for polarimetry. SEOP and MEOP are now widely applied for spin-polarized targets, neutron spin filters, magnetic resonance imaging, and precision measurements. PMID:29503479

Optically polarized 3He.

PubMed

Gentile, T R; Nacher, P J; Saam, B; Walker, T G

2017-01-01

This article reviews the physics and technology of producing large quantities of highly spin-polarized 3 He nuclei using spin-exchange (SEOP) and metastability-exchange (MEOP) optical pumping. Both technical developments and deeper understanding of the physical processes involved have led to substantial improvements in the capabilities of both methods. For SEOP, the use of spectrally narrowed lasers and K-Rb mixtures has substantially increased the achievable polarization and polarizing rate. For MEOP nearly lossless compression allows for rapid production of polarized 3 He and operation in high magnetic fields has likewise significantly increased the pressure at which this method can be performed, and revealed new phenomena. Both methods have benefitted from development of storage methods that allow for spin-relaxation times of hundreds of hours, and specialized precision methods for polarimetry. SEOP and MEOP are now widely applied for spin-polarized targets, neutron spin filters, magnetic resonance imaging, and precision measurements.

Optically polarized 3He

NASA Astrophysics Data System (ADS)

Gentile, T. R.; Nacher, P. J.; Saam, B.; Walker, T. G.

2017-10-01

This article reviews the physics and technology of producing large quantities of highly spin-polarized 3He nuclei using spin-exchange (SEOP) and metastability-exchange (MEOP) optical pumping. Both technical developments and deeper understanding of the physical processes involved have led to substantial improvements in the capabilities of both methods. For SEOP, the use of spectrally narrowed lasers and K-Rb mixtures has substantially increased the achievable polarization and polarizing rate. For MEOP nearly lossless compression allows for rapid production of polarized 3He and operation in high magnetic fields has likewise significantly increased the pressure at which this method can be performed, and revealed new phenomena. Both methods have benefitted from development of storage methods that allow for spin-relaxation times of hundreds of hours, and specialized precision methods for polarimetry. SEOP and MEOP are now widely applied for spin-polarized targets, neutron spin filters, magnetic resonance imaging, and precision measurements.

Applications of He's semi-inverse method, ITEM and GGM to the Davey-Stewartson equation

NASA Astrophysics Data System (ADS)

Zinati, Reza Farshbaf; Manafian, Jalil

2017-04-01

We investigate the Davey-Stewartson (DS) equation. Travelling wave solutions were found. In this paper, we demonstrate the effectiveness of the analytical methods, namely, He's semi-inverse variational principle method (SIVPM), the improved tan(φ/2)-expansion method (ITEM) and generalized G'/G-expansion method (GGM) for seeking more exact solutions via the DS equation. These methods are direct, concise and simple to implement compared to other existing methods. The exact solutions containing four types solutions have been achieved. The results demonstrate that the aforementioned methods are more efficient than the Ansatz method applied by Mirzazadeh (2015). Abundant exact travelling wave solutions including solitons, kink, periodic and rational solutions have been found by the improved tan(φ/2)-expansion and generalized G'/G-expansion methods. By He's semi-inverse variational principle we have obtained dark and bright soliton wave solutions. Also, the obtained semi-inverse variational principle has profound implications in physical understandings. These solutions might play important role in engineering and physics fields. Moreover, by using Matlab, some graphical simulations were done to see the behavior of these solutions.

[Study of "Bishu Yakuen Ransho-Roku (the origin of herb garden in Owari Clan)].

PubMed

Goto, T; Yamaguchi, S; Tanaka, T

1995-01-01

"Bishu Yakuen Ransho-Roku (The origin of herb garden in Owari Clan)" is in the possession of the Institution of Tokugawa Rinseishi in Tokyo. This paper was written about the origin of the herb garden established by Mr. Shinken Mimura, an herbalist in the Owari clan between 1735 and 1746. Mr. Shinken Mimura cultivated ginseng by according to the guide issued by the shogunate, but he found the methods unsuitable. Therefore, he made efforts to improve the cultivation of ginseng. As a result, he succeeded in the cultivation of good ginseng. He had contributed to the development of the production of ginseng in the Owari clan. He write this document so that his methods could be handed down for posterity. This document has two parts: one is the growth of ginseng in the form of a diary and the other is the conditions of cultivation as to seeding, fertilization, the counter-measures for damage due to blight and insects, and so on.

Positive Ion Induced Solidification of He4

NASA Astrophysics Data System (ADS)

Moroshkin, P.; Lebedev, V.; Weis, A.

2009-03-01

We have observed bulk solidification of He4 induced by nucleation on positive alkali ions in pressurized superfluid helium. The ions are extracted into the liquid from alkali-doped solid He by a static electric field. The experiments prove the existence of charged particles in a solid structure composed of doped He that was recently shown to coexist with superfluid helium below the He solidification pressure. This supports our earlier suggestion that the Coulomb interaction of positive ions surrounded by a solid He shell (snowballs) and electrons trapped in spherical cavities (electron bubbles), together with surface tension, is responsible for the stability of that structure against melting. We have determined the density of charges in the sample by two independent methods.

DEVELOPMENT OF DECISION MAKING ALGORITHM FOR CONTROL OF SEA CARGO CONTAINERS BY 'TAGGED' NEUTRON METHOD

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

Anan'ev, A. A.; Belichenko, S. G.; Bogolyubov, E. P.

Nowadays in Russia and abroad there are several groups of scientists, engaged in development of systems based on 'tagged' neutron method (API method) and intended for detection of dangerous materials, including high explosives (HE). Particular attention is paid to possibility of detection of dangerous objects inside a sea cargo container. Energy gamma-spectrum, registered from object under inspection is used for determination of oxygen/carbon and nitrogen/carbon chemical ratios, according to which dangerous object is distinguished from not dangerous one. Material of filled container, however, gives rise to additional effects of rescattering and moderation of 14 MeV primary neutrons of generator, attenuationmore » of secondary gamma-radiation from reactions of inelastic neutron scattering on objects under inspection. These effects lead to distortion of energy gamma-response from examined object and therefore prevent correct recognition of chemical ratios. These difficulties are taken into account in analytical method, presented in the paper. Method has been validated against experimental data, obtained by the system for HE detection in sea cargo, based on API method and developed in VNIIA. Influence of shielding materials on results of HE detection and identification is considered. Wood and iron were used as shielding materials. Results of method application for analysis of experimental data on HE simulator measurement (tetryl, trotyl, hexogen) are presented.« less

Laser Ablation in situ (U-Th-Sm)/He and U-Pb Double-Dating of Apatite and Zircon: Techniques and Applications

NASA Astrophysics Data System (ADS)

McInnes, B.; Danišík, M.; Evans, N.; McDonald, B.; Becker, T.; Vermeesch, P.

2015-12-01

We present a new laser-based technique for rapid, quantitative and automated in situ microanalysis of U, Th, Sm, Pb and He for applications in geochronology, thermochronometry and geochemistry (Evans et al., 2015). This novel capability permits a detailed interrogation of the time-temperature history of rocks containing apatite, zircon and other accessory phases by providing both (U-Th-Sm)/He and U-Pb ages (+trace element analysis) on single crystals. In situ laser microanalysis offers several advantages over conventional bulk crystal methods in terms of safety, cost, productivity and spatial resolution. We developed and integrated a suite of analytical instruments including a 193 nm ArF excimer laser system (RESOlution M-50A-LR), a quadrupole ICP-MS (Agilent 7700s), an Alphachron helium mass spectrometry system and swappable flow-through and ultra-high vacuum analytical chambers. The analytical protocols include the following steps: mounting/polishing in PFA Teflon using methods similar to those adopted for fission track etching; laser He extraction and analysis using a 2 s ablation at 5 Hz and 2-3 J/cm2fluence; He pit volume measurement using atomic force microscopy, and U-Th-Sm-Pb (plus optional trace element) analysis using traditional laser ablation methods. The major analytical challenges for apatite include the low U, Th and He contents relative to zircon and the elevated common Pb content. On the other hand, apatite typically has less extreme and less complex zoning of parent isotopes (primarily U and Th). A freeware application has been developed for determining (U-Th-Sm)/He ages from the raw analytical data and Iolite software was used for U-Pb age and trace element determination. In situ double-dating has successfully replicated conventional U-Pb and (U-Th)/He age variations in xenocrystic zircon from the diamondiferous Ellendale lamproite pipe, Western Australia and increased zircon analytical throughput by a factor of 50 over conventional methods.Reference: Evans NJ, McInnes BIA, McDonald B, Becker T, Vermeesch P, Danisik M, Shelley M, Marillo-Sialer E and Patterson D. An in situ technique for (U-Th-Sm)/He and U-Pb double dating. J Analytical Atomic Spectrometry, 30, 1636 - 1645.

Photoabsorption spectra of small HeN+ clusters (N = 3, 4, 10). A quantum Monte Carlo modeling

NASA Astrophysics Data System (ADS)

Ćosić, Rajko; Karlický, František; Kalus, René

2018-05-01

Photoabsorption cross-sections have been calculated for HeN+ clusters of selected sizes (N = 3, 4, 10) over a broad range of photon energies (Ephot = 2 - 14 eV) and compared with available experimental data. Semiempirical electronic Hamiltonians derived from the diatomics-in-molecules approach have been used for electronic structure calculations and a quantum, path-integral Monte Carlo method has been employed to model the delocalization of helium nuclei. While a quantitative agreement has been achieved between the theory and experiment for He3+ and He4+, only qualitative correspondence is seen for He10+ .

Adaptation of Foreign Students to the Foreign Culture Learning Environment Using the Six Thinking Hats Method

ERIC Educational Resources Information Center

Stanislavovna, Vershinina Tatiana; Leopoldovna, Kocheva Olga

2015-01-01

The contemporary life is characterized by various ways and forms of communication, sometimes but not always successful and leading to conflict situations. When a man occurs in the environment, alien to him, he meets misunderstanding and is overwhelmed with incomprehensible emotions as if he were covered with an avalanche. He has to solve problems…

Public Experiments and Their Analysis with the Replication Method

ERIC Educational Resources Information Center

Heering, Peter

2007-01-01

One of those who failed to establish himself as a natural philosopher in 18th century Paris was the future revolutionary Jean Paul Marat. He did not only publish several monographs on heat, optics and electricity in which he attempted to characterise his work as being purely empirical but he also tried to establish himself as a public lecturer.…

Immunohistochemical localization of HE4 in benign, borderline, and malignant lesions of the ovary.

PubMed

Georgakopoulos, Penelope; Mehmood, Saira; Akalin, Ali; Shroyer, Kenneth R

2012-11-01

Despite advances in the development of novel methods to improve treatment, ovarian carcinoma is still the leading cause of gynecologic cancer death in the United States and other industrialized nations. Improvements in the clinical outcome of ovarian cancer will be achieved if methods can be developed to enable the detection of these tumors at the earliest possible stage. Thus, it is critically important to identify and validate new biomarkers of ovarian cancer. HE4 expression was defined by immunohistochemical analysis of a wide range of benign, borderline, and malignant ovarian lesions, including serous, endometrioid, mucinous, and clear cell lesions of the ovary and in primary tubal carcinomas and the normal fallopian tube. At the cellular level, HE4 was highly expressed in malignant ovarian tumors and in a wide range of benign and borderline ovarian lesions. In addition, HE4 was highly expressed in primary fallopian tube carcinomas and benign fallopian tubal epithelial cells. These results support the conclusion that HE4 is widely expressed in most benign, borderline, and malignant lesions of the ovary and the fallopian tube. The detection of HE4 expression at high levels in some benign lesions and normal tissues suggests that HE4 could have limited specificity as a marker of ovarian or tubal carcinoma. Furthermore, the relatively weak expression that was observed in many ovarian carcinomas indicates that HE4 could fail to detect some cases of primary or recurrent disease.

Assessing the use of 3H-3He dating to determine the subsurface transit time of cave drip waters.

PubMed

Kluge, Tobias; Wieser, Martin; Aeschbach-Hertig, Werner

2010-09-01

(3)H-(3)He measurements constitute a well-established method for the determination of the residence time of young groundwater. However, this method has rarely been applied to karstified aquifers and in particular to drip water in caves, despite the importance of the information which may be obtained. Besides the determination of transfer times of climate signals from the atmosphere through the epikarst to speleothems as climate archives, (3)H-(3)He together with Ne, Ar, Kr, Xe data may also help to give new insights into the local hydrogeology, e.g. the possible existence of a perched aquifer above a cave. In order to check the applicability of (3)H-(3)He dating to cave drips, we collected drip water samples from three adjacent caves in northwestern Germany during several campaigns. The noble gas data were evaluated by inverse modelling to obtain recharge temperature and excess air, supporting the calculation of the tritiogenic (3)He and hence the (3)H-(3)He age. Although atmospheric noble gases were often found to be close to equilibrium with the cave atmosphere, several drip water samples yielded an elevated (3)He/(4)He ratio, providing evidence for the accumulation of (3)He from the decay of (3)H. No significant contribution of radiogenic (4)He was found, corresponding to the low residence times mostly in the range of one to three years. Despite complications during sampling, conditions of a perched aquifer could be confirmed by replicate samples at one drip site. Here, the excess air indicator ΔNe was about 10 %, comparable to typical values found in aquifers in mid-latitudes. The mean (3)H-(3)He age of 2.1 years at this site presumably refers to the residence time in the perched aquifer and is lower than the entire transit time of 3.4 years estimated from the tritium data.

Anticancer Activity of a Hexapeptide from Skate (Raja porosa) Cartilage Protein Hydrolysate in HeLa Cells

PubMed Central

Pan, Xin; Zhao, Yu-Qin; Hu, Fa-Yuan; Chi, Chang-Feng; Wang, Bin

2016-01-01

In this study, the hexapeptide Phe-Ile-Met-Gly-Pro-Tyr (FIMGPY), which has a molecular weight of 726.9 Da, was separated from skate (Raja porosa) cartilage protein hydrolysate using ultrafiltration and chromatographic methods, and its anticancer activity was evaluated in HeLa cells. Methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay indicated that FIMGPY exhibited high, dose-dependent anti-proliferation activities in HeLa cells with an IC50 of 4.81 mg/mL. Acridine orange/ethidium bromide (AO/EB) fluorescence staining and flow cytometry methods confirmed that FIMGPY could inhibit HeLa cell proliferation by inducing apoptosis. Western blot assay revealed that the Bax/Bcl-2 ratio and relative intensity of caspase-3 in HeLa cells treated with 7-mg/mL FIMGPY were 2.63 and 1.83, respectively, significantly higher than those of the blank control (p < 0.01). Thus, FIMGPY could induce apoptosis by upregulating the Bax/Bcl-2 ratio and caspase-3 activation. Using a DNA ladder method further confirmed that the anti-proliferation activity of FIMGPY was attributable to its role in inducing apoptosis. These results suggest that FIMGPY from skate cartilage protein hydrolysate may have applications as functional foods and nutraceuticals for the treatment and prevention of cancer. PMID:27537897

Anticancer Activity of a Hexapeptide from Skate (Raja porosa) Cartilage Protein Hydrolysate in HeLa Cells.

PubMed

Pan, Xin; Zhao, Yu-Qin; Hu, Fa-Yuan; Chi, Chang-Feng; Wang, Bin

2016-08-16

In this study, the hexapeptide Phe-Ile-Met-Gly-Pro-Tyr (FIMGPY), which has a molecular weight of 726.9 Da, was separated from skate (Raja porosa) cartilage protein hydrolysate using ultrafiltration and chromatographic methods, and its anticancer activity was evaluated in HeLa cells. Methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay indicated that FIMGPY exhibited high, dose-dependent anti-proliferation activities in HeLa cells with an IC50 of 4.81 mg/mL. Acridine orange/ethidium bromide (AO/EB) fluorescence staining and flow cytometry methods confirmed that FIMGPY could inhibit HeLa cell proliferation by inducing apoptosis. Western blot assay revealed that the Bax/Bcl-2 ratio and relative intensity of caspase-3 in HeLa cells treated with 7-mg/mL FIMGPY were 2.63 and 1.83, respectively, significantly higher than those of the blank control (p < 0.01). Thus, FIMGPY could induce apoptosis by upregulating the Bax/Bcl-2 ratio and caspase-3 activation. Using a DNA ladder method further confirmed that the anti-proliferation activity of FIMGPY was attributable to its role in inducing apoptosis. These results suggest that FIMGPY from skate cartilage protein hydrolysate may have applications as functional foods and nutraceuticals for the treatment and prevention of cancer.

Compressing Spin-Polarized 3He With a Modified Diaphragm Pump

PubMed Central

Gentile, T. R.; Rich, D. R.; Thompson, A. K.; Snow, W. M.; Jones, G. L.

2001-01-01

Nuclear spin-polarized 3He gas at pressures on the order of 100 kPa (1 bar) are required for several applications, such as neutron spin filters and magnetic resonance imaging. The metastability-exchange optical pumping (MEOP) method for polarizing 3He gas can rapidly produce highly polarized gas, but the best results are obtained at much lower pressure (~0.1 kPa). We describe a compact compression apparatus for polarized gas that is based on a modified commercial diaphragm pump. The gas is polarized by MEOP at a typical pressure of 0.25 kPa (2.5 mbar), and compressed into a storage cell at a typical pressure of 100 kPa. In the storage cell, we have obtained 20 % to 35 % 3He polarization using pure 3He gas and 35 % to 50 % 3He polarization using 3He-4He mixtures. By maintaining the storage cell at liquid nitrogen temperature during compression, the density has been increased by a factor of four. PMID:27500044

Probing He bubbles in naturally aged and annealed δ-Pu alloys using ultra-small-angle x-ray scattering

DOE PAGES

Jeffries, J. R.; Hammons, J. A.; Willey, T. M.; ...

2017-10-31

We report the self-irradiation of Pu alloys generates He that is trapped within the metal matrix in the form of He bubbles. The distribution of these He bubbles in δ-phase Pu-Ga alloys exhibits a peak near a radius of 0.7 nm, and this size is remarkably stable as function of time. When annealed, the He bubbles in δ-Pu alloys grow, coarsening the distribution. However, the magnitude of this coarsening is uncertain, as different experimental methods reveal bubbles that differ by at least one order of magnitude. Small-angle x-ray scattering results, which can probe a wide range of bubble sizes, implymore » only a mild coarsening of the He bubble distribution for an annealing treatment of 425 °C for 24 h, and analysis of the He bubble content suggests that He is actually lost from the bubbles with annealing.« less

Experimental study of fusion neutron and proton yields produced by petawatt-laser-irradiated D₂-³He or CD₄-³He clustering gases.

PubMed

Bang, W; Barbui, M; Bonasera, A; Quevedo, H J; Dyer, G; Bernstein, A C; Hagel, K; Schmidt, K; Gaul, E; Donovan, M E; Consoli, F; De Angelis, R; Andreoli, P; Barbarino, M; Kimura, S; Mazzocco, M; Natowitz, J B; Ditmire, T

2013-09-01

We report on experiments in which the Texas Petawatt laser irradiated a mixture of deuterium or deuterated methane clusters and helium-3 gas, generating three types of nuclear fusion reactions: D(d,^{3}He)n, D(d,t)p, and ^{3}He(d,p)^{4}He. We measured the yields of fusion neutrons and protons from these reactions and found them to agree with yields based on a simple cylindrical plasma model using known cross sections and measured plasma parameters. Within our measurement errors, the fusion products were isotropically distributed. Plasma temperatures, important for the cross sections, were determined by two independent methods: (1) deuterium ion time of flight and (2) utilizing the ratio of neutron yield to proton yield from D(d,^{3}He)n and ^{3}He(d,p)^{4}He reactions, respectively. This experiment produced the highest ion temperature ever achieved with laser-irradiated deuterium clusters.

A Review of Teaching Methods--Lecturing and Facilitation in Higher Education (HE): A Summary of the Published Evidence

ERIC Educational Resources Information Center

Regmi, Krishna

2012-01-01

Several studies have documented that teaching methods in HE (generally involves work towards a university or college level education), are the most important aspect of a curriculum. This is because they serve as an interface between the learners and the philosophy of the curriculum. It is, however, difficult to define how knowledge is…

Amphiaraos of Attica: the "Second Asclepius".

PubMed

Iavazzo, Christos; Gkegkes, Ioannis D; Gkegke, Xanthi-Ekaterini D; Ntziora, Fotinie

2012-01-01

Amphiaraos is one of the most prominent Greek heroes. He was the son of god Apollo and student of Centaur Chiron from whom he learned the art of medicine. He was thought to be the "Second Asclepius" and he had many sanctuaries around Greece of which the most well known is the Amphiaraeion of Oropos, near Athens. The aim of this study is to present the genealogical tree and life of Amphiaraos, as well as the methods used in his sanctuaries in order to offer cure in the ill pilgrims.

Alexis Carrel (1873-1944): visionary vascular surgeon and pioneer in organ transplantation.

PubMed

Aida, Lai

2014-08-01

Alexis Carrel was a French surgeon in the 20th century. He made significant contributions to many advances in the fields of vascular surgery, cardiothoracic surgery and organ transplantation. He demonstrated that blood vessels can be united end-to-end and pioneered the triangulation suturing technique in vascular anastomosis. The methods he developed are still in use to this day. He insisted on the importance of absolute asepsis in vascular surgery when such practices were almost unheard of. He was also considered the father of solid organ transplantation. He was awarded the Nobel Prize in recognition of his work. Together with Charles Lindbergh, he developed the extracorporeal perfusion pump to keep organs alive outside the human body. His contribution to medicine also extended to tissue culture and wound management. He was one of the most controversial figures of his generation, believing in the idea of genetic superiority and eugenics and he was associated with fascism in the 1930s. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Ground-state energy of HeH{sup +}

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

Zhou Binglu; Zhu Jiongming; Yan Zongchao

2006-06-15

The nonrelativistic ground-state energy of {sup 4}HeH{sup +} is calculated using a variational method in Hylleraas coordinates. Convergence to a few parts in 10{sup 10} is achieved, which improves the best previous result of Pavanello et al. [J. Chem. Phys. 123, 104306 (2005)]. Expectation values of the interparticle distances are evaluated. Similar results for {sup 3}HeH{sup +} are also presented.

Poiseuille's Law--Showing that "p" Is Inversely Proportional to R[superscript 4] Using the Shell Method

ERIC Educational Resources Information Center

Drost, John P.; Georges, Rachel A.

2004-01-01

Jean Poiseuille, a physician, developed a mercury filled U-tube to measure blood pressure in 1828. He discovered that pressure in veins is significantly lower than pressure in arteries. As a result, he studied liquid flow in small tubes. A few years later he established Poiseuille's Law, which states the resistance, "p," of the flow of blood as…

Measurement of differential cross section of D(3He,p)4He from 0.8 MeV to 3.6 MeV

NASA Astrophysics Data System (ADS)

Zhu, J. P.; Xiao, X.; Yan, S.; Gao, Y.; Xue, J. M.; Wang, Y. G.

2017-12-01

Precise knowledge of the nuclear reaction cross-section is crucial for nuclear reaction analysis methods and its applications. In order to apply nuclear reaction analysis methods to Plasma Facing Materials studies on 4.5 MV electrostatic accelerator at Peking University, differential cross-section for d(3He,p) α at several backward angles was measured with a relative error about ± 6.2 % , gives detailed information at the laboratory angle of 135° from 800 keV to 3600 keV, as well as a rough angular distribution from 130° to 160°.

Agreement between clinical estimation and a new quantitative analysis by Photoshop software in fundus and angiographic image variables.

PubMed

Ramezani, Alireza; Ahmadieh, Hamid; Azarmina, Mohsen; Soheilian, Masoud; Dehghan, Mohammad H; Mohebbi, Mohammad R

2009-12-01

To evaluate the validity of a new method for the quantitative analysis of fundus or angiographic images using Photoshop 7.0 (Adobe, USA) software by comparing with clinical evaluation. Four hundred and eighteen fundus and angiographic images of diabetic patients were evaluated by three retina specialists and then by computing using Photoshop 7.0 software. Four variables were selected for comparison: amount of hard exudates (HE) on color pictures, amount of HE on red-free pictures, severity of leakage, and the size of the foveal avascular zone (FAZ). The coefficient of agreement (Kappa) between the two methods in the amount of HE on color and red-free photographs were 85% (0.69) and 79% (0.59), respectively. The agreement for severity of leakage was 72% (0.46). In the two methods for the evaluation of the FAZ size using the magic and lasso software tools, the agreement was 54% (0.09) and 89% (0.77), respectively. Agreement in the estimation of the FAZ size by the lasso magnetic tool was excellent and was almost as good in the quantification of HE on color and on red-free images. Considering the agreement of this new technique for the measurement of variables in fundus images using Photoshop software with the clinical evaluation, this method seems to have sufficient validity to be used for the quantitative analysis of HE, leakage, and FAZ size on the angiograms of diabetic patients.

Developing a new, passive diffusion sampling array to detect helium anomalies associated with volcanic unrest

USGS Publications Warehouse

Dame, Brittany E; Solomon, D Kip; Evans, William C.; Ingebritsen, Steven E.

2015-01-01

Helium (He) concentration and 3 He/ 4 He anomalies in soil gas and spring water are potentially powerful tools for investigating hydrothermal circulation associated with volca- nism and could perhaps serve as part of a hazards warning system. However, in operational practice, He and other gases are often sampled only after volcanic unrest is detected by other means. A new passive diffusion sampler suite, intended to be collected after the onset of unrest, has been developed and tested as a relatively low-cost method of determining He- isotope composition pre- and post-unrest. The samplers, each with a distinct equilibration time, passively record He concen- tration and isotope ratio in springs and soil gas. Once collected and analyzed, the He concentrations in the samplers are used to deconvolve the time history of the He concentration and the 3 He/ 4 He ratio at the collection site. The current suite consisting of three samplers is sufficient to deconvolve both the magnitude and the timing of a step change in in situ con- centration if the suite is collected within 100 h of the change. The effects of temperature and prolonged deployment on the suite ’ s capability of recording He anomalies have also been evaluated. The suite has captured a significant 3 He/ 4 He soil gas anomaly at Horseshoe Lake near Mammoth Lakes, California. The passive diffusion sampler suite appears to be an accurate and affordable alternative for determining He anomalies associated with volcanic unrest.

Emergence of the bipolar cultural complex in Walt Whitman.

PubMed

Herrmann, Steven B

2007-09-01

My main hypothesis in this paper(1) is that America's seminal poet, Walt Whitman, was trapped--like so many of his contemporaries--in 'cultural complexes' (Singer & Kimbles 2004) that he internalized, but that he found a way to transcend the splits inherent in these 'bipolar' (Perry 1970) organizations through his art. One way he accomplished this was through his aesthetic method of 'holding the opposites' between two poles of a slavery is wrong/white supremacy is justified cultural complex. In my paper, I provide evidence for some of the contradictions inherent in Whitman's character by examining the political splits of his times and explore how various Self symbols he produced through his poetry, particularly the figures he called 'Black Lucifer' and the Deus Quadriune--a quaternity symbol--facilitated his personal and cultural transformation. Finally, I demonstrate the relevance of my hypothesis to contemporary racism during the pre-Civil Rights period in the South through a clinical example, and I show how the Jungian method of 'holding the opposites' can be effectively practised in the transference/countertransference field of psychotherapy in general.

[Claude Bernard, the experimental method, and the Société de Biologie].

PubMed

Bange, Christian

2009-01-01

Claude Bernard was one of the founder of the Société de Biologie created in 1849. He actively took part to it from its very beginning by presenting various communications and several important memoirs. Epistemological thoughts found in these memoirs lead to the methodological chapters introducing the volumes of his edited lessons given at the Collège de France. In 1865, these texts formed the basis to his Introduction à l'étude de la Médecine expérimentale, in which Bernard claims the experimental method should rely on the principle of determinism of the phenomena of Life. He was a dutiful President of the Société from 1867 until his death. He nevertheless was not often involved in debates, but agreed on the defense of the scientific principles he had claimed. He remained influential until his death, as noted in 1899 by the report Engène Gley wrote on the Société de Biologie during its fifty first years. Gley points regularly to Bernard's axioms which remained the true scientific credo of French biologists.

Improved neutron-gamma discrimination for a 3He neutron detector using subspace learning methods

DOE PAGES

Wang, C. L.; Funk, L. L.; Riedel, R. A.; ...

2017-02-10

3He gas based neutron linear-position-sensitive detectors (LPSDs) have been applied for many neutron scattering instruments. Traditional Pulse-Height Analysis (PHA) for Neutron-Gamma Discrimination (NGD) resulted in the neutron-gamma efficiency ratio on the orders of 10 5-10 6. The NGD ratios of 3He detectors need to be improved for even better scientific results from neutron scattering. Digital Signal Processing (DSP) analyses of waveforms were proposed for obtaining better NGD ratios, based on features extracted from rise-time, pulse amplitude, charge integration, a simplified Wiener filter, and the cross-correlation between individual and template waveforms of neutron and gamma events. Fisher linear discriminant analysis (FLDA)more » and three multivariate analyses (MVAs) of the features were performed. The NGD ratios are improved by about 10 2-10 3 times compared with the traditional PHA method. Finally, our results indicate the NGD capabilities of 3He tube detectors can be significantly improved with subspace-learning based methods, which may result in a reduced data-collection time and better data quality for further data reduction.« less

Long-time atomistic dynamics through a new self-adaptive accelerated molecular dynamics method

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

Gao, N.; Yang, L.; Gao, F.

2017-02-27

A self-adaptive accelerated molecular dynamics method is developed to model infrequent atomic- scale events, especially those events that occur on a rugged free-energy surface. Key in the new development is the use of the total displacement of the system at a given temperature to construct a boost-potential, which is slowly increased to accelerate the dynamics. The temperature is slowly increased to accelerate the dynamics. By allowing the system to evolve from one steady-state con guration to another by overcoming the transition state, this self-evolving approach makes it possible to explore the coupled motion of species that migrate on vastly differentmore » time scales. The migrations of single vacancy (V) and small He-V clusters, and the growth of nano-sized He-V clusters in Fe for times in the order of seconds are studied by this new method. An interstitial- assisted mechanism is rst explored for the migration of a helium-rich He-V cluster, while a new two-component Ostwald ripening mechanism is suggested for He-V cluster growth.« less

Automatic variance reduction for Monte Carlo simulations via the local importance function transform

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

Turner, S.A.

1996-02-01

The author derives a transformed transport problem that can be solved theoretically by analog Monte Carlo with zero variance. However, the Monte Carlo simulation of this transformed problem cannot be implemented in practice, so he develops a method for approximating it. The approximation to the zero variance method consists of replacing the continuous adjoint transport solution in the transformed transport problem by a piecewise continuous approximation containing local biasing parameters obtained from a deterministic calculation. He uses the transport and collision processes of the transformed problem to bias distance-to-collision and selection of post-collision energy groups and trajectories in a traditionalmore » Monte Carlo simulation of ``real`` particles. He refers to the resulting variance reduction method as the Local Importance Function Transform (LIFI) method. He demonstrates the efficiency of the LIFT method for several 3-D, linearly anisotropic scattering, one-group, and multigroup problems. In these problems the LIFT method is shown to be more efficient than the AVATAR scheme, which is one of the best variance reduction techniques currently available in a state-of-the-art Monte Carlo code. For most of the problems considered, the LIFT method produces higher figures of merit than AVATAR, even when the LIFT method is used as a ``black box``. There are some problems that cause trouble for most variance reduction techniques, and the LIFT method is no exception. For example, the author demonstrates that problems with voids, or low density regions, can cause a reduction in the efficiency of the LIFT method. However, the LIFT method still performs better than survival biasing and AVATAR in these difficult cases.« less

Respondeo: method and content in casuistry.

PubMed

Wildes, Kevin Wm

1994-02-01

James Tallmon has argued that my criticisms of Jonsen and Toulmin are ill founded. Tallmon argues that Jonsen and Toulmin argue for a method of rhetorical reasoning and not for a particular content. He argues that if one distinguishes the content and method of casuistry the Jonsen-Toulmin model can work. But Tallmon, like Jonsen and Toulmin, cannot escape the need for casuistry to have a content. Tallmon's response evidences that need since he assumes that there is a 'Medical Community' which has a moral vision.

Radiogenic 4He as a conservative tracer in buried‐valley aquifers

USGS Publications Warehouse

Van der Hoven, Stephen J.; Wright, R. Erik; Carstens, David A.; Hackley, Keith C.

2005-01-01

The accumulation of 4He in groundwater can be a powerful tool in hydrogeologic investigations. However, the use of 4He often suffers from disagreement or uncertainty related to in situ and external sources of 4He. In situ sources are quantified by several methods, while external sources are often treated as calibration parameters in modeling. We present data from direct laboratory measurements of 4He release from sediments and field data of dissolved 4He in the Mahomet Aquifer, a well‐studied buried‐valley aquifer in central Illinois. The laboratory‐derived accumulation rates (0.13–0.91 μcm3 STP kgwater−1 yr−1) are 1–2 orders of magnitude greater than the accumulation rates based on the U and Th concentrations of the sediments (0.004–0.009 μcm3 STP kgwater−1 yr−1). The direct measurement of accumulation rates are more consistent with dissolved concentrations of 4He in the groundwater. We suggest that the direct measurement method is applicable in a variety of hydrogeologic settings. The patterns of accumulation of 4He are consistent with the conceptual model of flow in the aquifer based on hydraulic and geochemical evidence and show areas where in situ production and external sources of 4He are dominant. In the southwestern part of the study area, Ne concentrations are less than atmospheric solubility, indicating gases have been lost from the groundwater. Available evidence indicates that the gases are lost as groundwater passes by pockets of CH4 in glacial deposits overlying the aquifer. However, the external flux from the underlying bedrock appears to dominate the accumulation of radiogenic 4He in the aquifer in the southwestern part of the study area, and the loss or gain of helium as groundwater passes through the overlying sediments is minor in comparison.

A measurement of the absolute neutron beam polarization produced by an optically pumped 3He neutron spin filter

NASA Astrophysics Data System (ADS)

Rich, D. R.; Bowman, J. D.; Crawford, B. E.; Delheij, P. P. J.; Espy, M. A.; Haseyama, T.; Jones, G.; Keith, C. D.; Knudson, J.; Leuschner, M. B.; Masaike, A.; Masuda, Y.; Matsuda, Y.; Penttilä, S. I.; Pomeroy, V. R.; Smith, D. A.; Snow, W. M.; Szymanski, J. J.; Stephenson, S. L.; Thompson, A. K.; Yuan, V.

2002-04-01

The capability of performing accurate absolute measurements of neutron beam polarization opens a number of exciting opportunities in fundamental neutron physics and in neutron scattering. At the LANSCE pulsed neutron source we have measured the neutron beam polarization with an absolute accuracy of 0.3% in the neutron energy range from 40 meV to 10 eV using an optically pumped polarized 3He spin filter and a relative transmission measurement technique. 3He was polarized using the Rb spin-exchange method. We describe the measurement technique, present our results, and discuss some of the systematic effects associated with the method.

Public Experiments and their Analysis with the Replication Method

NASA Astrophysics Data System (ADS)

Heering, Peter

2007-06-01

One of those who failed to establish himself as a natural philosopher in 18th century Paris was the future revolutionary Jean Paul Marat. He did not only publish several monographs on heat, optics and electricity in which he attempted to characterise his work as being purely empirical but he also tried to establish himself as a public lecturer. From the analysis of his experiments using the replication method it became obvious that the written description is missing several relevant aspects of the experiments. In my paper, I am going to discuss the experiences made in analysing these experiments and will suggest possible relations between these publications and the public demonstrations.

Facile time-of-flight methods for characterizing pulsed superfluid helium droplet beams

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

He, Yunteng; Zhang, Jie; Li, Yang

2015-08-15

We present two facile time-of-flight (TOF) methods of detecting superfluid helium droplets and droplets with neutral dopants. Without an electron gun and with only a heated filament and pulsed electrodes, the electron impact ionization TOF mass spectrometer can resolve ionized helium clusters such as He{sub 2}{sup +} and He{sub 4}{sup +}, which are signatures of superfluid helium droplets. Without ionizing any helium atoms, multiphoton non-resonant laser ionization of CCl{sub 4} doped in superfluid helium droplets at 266 nm generates complex cluster ions of dopant fragments with helium atoms, including (He){sub n}C{sup +}, (He){sub n}Cl{sup +}, and (He){sub n}CCl{sup +}. Usingmore » both methods, we have characterized our cryogenic pulsed valve—the Even-Lavie valve. We have observed a primary pulse with larger helium droplets traveling at a slower speed and a rebound pulse with smaller droplets at a faster speed. In addition, the pickup efficiency of dopant is higher for the primary pulse when the nozzle temperature is higher than 13 K, and the total time duration of the doped droplet pulse is only on the order of 20 μs. These results stress the importance of fast and easy characterization of the droplet beam for sensitive measurements such as electron diffraction of doped droplets.« less

[Comparison of Doppler-assisted dearterialization with mucopexy and hemorrhoidectomy].

PubMed

Titov, A Iu; Abritsova, M V; Mudrov, A A

2016-01-01

To compare two methods of hemorrhoid treatment. This prospective study included 240 patients with hemorrhoids stage III-IVA. Stages III and IVA were diagnosed in 156 (65%) and 84 (35%) patients respectively. Randomization was performed using envelopes method in one to one distribution. In group 1 (n=120) Doppler-assisted dearterialization of internal hemorrhoids with mucopexy was performed (DDM), in group 2 (n=120) - hemorrhoidectomy using harmonic scalpel (HE). Duration of surgery was 17.9±6.1 and 34.5±10.1 minutes in DDM and HE groups respectively (p<0.01). Postoperative pain severity was higher in group 2 (4.8 compared with 2.5 scores of the first group (p<0.01). Narcotic analgesics were used less often in DDM group (1.3 doses compared with 6.1 doses in HE group (p<0.01). Disability period was 14.4±5.2 and 30.3±5.4 days in both groups respectively (p<0.01). Immediate postoperative complications occurred in 9 (7.5%) and 19 (15.8%) patients of DDM and HE groups respectively. Recurrent prolapse of internal hemorrhoids was diagnosed in 2 (1.7%) patients of the 1st group in terms of up to 45 days. DDM is reliable minimally invasive method of hemorrhoids stage III-IVA treatment and has similar efficacy with HE. DDM reduces postoperative pain severity, hospital stay and disability period.

Comparison of bioimpedance methods for estimating total body water and intracellular water changes during hemodialysis.

PubMed

Dou, Yanna; Liu, Li; Cheng, Xuyang; Cao, Liyun; Zuo, Li

2011-10-01

The accurate assessment of body fluid volume is important in many clinical situations. Hannan et al. proposed a single-frequency bioimpedance equation (HE) to calculate extracellular water (ECW) and total body water (TBW). There are two equations based on the bioimpedance spectroscopy (BIS) method for the evaluation of body fluid volume: Xitron equations (XE) and body composition spectroscopy equations (BCSE). The aim of the study was to compare the accuracy of these three equations in body fluid volume point estimation in maintenance hemodialysis (MHD) patients. The BIS method was performed in MHD patients before and after a hemodialysis (HD) session. TBW, ECW and intracellular water (ICW) were calculated by XE, BCSE and HE, respectively. Hydration status (HS) was calculated using inputs of XE, BCSE and HE. ICW before dialysis was compared to ICW after dialysis. The change of TBW and HS using different equations was compared to actual ultrafiltration volume (AUV) that was calculated as weight difference of pre- to postdialysis. Fifty MHD patients (27 females) were included in the study. Significant changes in ICW were observed using the XE and HE method with ultrafiltration (XE: 15.51 ± 5.07 versus 16.17 ± 5.34 L, P < 0.01; HE: 17.40 ± 5.13 versus 16.55 ± 4.71 L, P < 0.01). However, no significant ICW change was observed using BCSE (17.47 ± 4.35 versus 17.54 ± 4.36 L, P > 0.05). ΔTBW_XE and ΔTBW_HE were significantly different from AUV (XE 1.76 ± 0.89 versus 2.46 ± 0.89 L, P < 0.01; HE 4.16 ± 1.36 versus 2.46 ± 0.89 L, P < 0.01); however, ΔTBW_BCSE was much closer to AUV (2.27 ± 0.90 versus 2.46 ± 0.89 L, P = 0.129). The change of HS using inputs of BCSE was also closer to AUV (2.41 ± 0.86 versus 2.46 ± 0.89 L, P = 1.0). Our study indicated that BCSE provided a better point estimation of ICW and TBW.

Quasimolecular emission near the Xe(5p 56s 1,3 P 1 - 5p 6 1 S 0) and Kr (4p 55s 1,3 P 1 - 4p 6 1 S 0) resonance lines induced by collisions with He atoms

NASA Astrophysics Data System (ADS)

Alekseeva, O. S.; Devdariani, A. Z.; Grigorian, G. M.; Lednev, M. G.; Zagrebin, A. L.

2017-02-01

This study is devoted to the theoretical investigation of the quasimolecular emission of Xe*-He and Kr*-He collision pairs near the Xe (5p 56s 1,3 P 1 - 5p 6 1 S 0) and Kr (4p 55s 1,3 P 1 - 4p 6 1 S 0) resonance atomic lines. The potential curves of the quasimolecules Xe(5p 56s) + He and Kr(4p 55s) + He have been obtained with the use of the effective Hamiltonian and pseudopotential methods. Based on these potential curves the processes of quasimolecular emission of Xe*+He and Kr*+He mixtures have been considered and the spectral distributions I(ħΔω) of photons emitted have been obtained in the framework of quasistatic approximation.

Process-Driven Math: An Auditory Method of Mathematics Instruction and Assessment for Students Who Are Blind or Have Low Vision

ERIC Educational Resources Information Center

Gulley, Ann P.; Smith, Luke A.; Price, Jordan A.; Prickett, Logan C.; Ragland, Matthew F.

2017-01-01

Process-Driven Math is a fully audio method of mathematics instruction and assessment that was created at Auburn University at Montgomery, Alabama, to meet the needs of one particular student, Logan. He was blind, mobility impaired, and he could not speak above a whisper. Logan was not able to use traditional low vision tools like braille and…

Ionization of polarized 3He+ ions in EBIS trap with slanted electrostatic mirror.

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

Pikin,A.; Zelenski, A.; Kponou, A.

2007-09-10

Methods of producing the nuclear polarized {sup 3}He{sup +} ions and their ionization to {sup 3}H{sup ++} in ion trap of the electron Beam Ion Source (EBIS) are discussed. Computer simulations show that injection and accumulation of {sup 3}He{sup +} ions in the EBIS trap with slanted electrostatic mirror can be very effective for injection times longer than the ion traversal time through the trap.

Measurement of helium isotopes in soil gas as an indicator of tritium groundwater contamination.

PubMed

Olsen, Khris B; Dresel, P Evan; Evans, John C; McMahon, William J; Poreda, Robert

2006-05-01

The focus of this study was to define the shape and extent of tritium groundwater contamination emanating from a legacy burial ground and to identify vadose zone sources of tritium using helium isotopes (3He and 4He) in soil gas. Helium isotopes were measured in soil-gas samples collected from 70 sampling points around the perimeter and downgradient of a burial ground that contains buried radioactive solid waste. The soil-gas samples were analyzed for helium isotopes using rare gas mass spectrometry. 3He/4He ratios, reported as normalized to the air ratio (RA), were used to locate the tritium groundwater plume emanating from the burial ground. The 3He (excess) suggested that the general location of the tritium source is within the burial ground. This study clearly demonstrated the efficacy of the 3He method for application to similar sites elsewhere within the DOE weapons complex.

Compression-induced stacking fault tetrahedra around He bubbles in Al

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

Shao, Jian-Li, E-mail: shao-jianli@iapcm.ac.cn; Wang, Pei; He, An-Min

Classic molecular dynamics methods are used to simulate the uniform compression process of the fcc Al containing He bubbles. The formation of stacking fault tetrahedra (SFTs) during the collapse of He bubbles is found, and their dependence on the initial He bubble size (0.6–6 nm in diameter) is presented. Our simulations indicate only elastic deformation in the samples for the He bubble size not more than 2 nm. Instead, increasing the He bubble size, we detect several small SFTs forming on the surface of the He bubble (3 nm), as well as the two intercrossed SFTs around the He bubbles (4–6 nm). All thesemore » SFTs are observed to be stable under further compression, though there may appear some SF networks outside the SFTs (5–6 nm). Furthermore, the dynamic analysis on the SFTs shows that the yield pressure keeps a near-linear increase with the initial He bubble pressure, and the potential energy of Al atoms inside the SFTs is lower than outside because of their gliding inwards. In addition, the pressure increments of 2–6 nm He bubbles with strain are less than that of Al, which just provides the opportunity for the He bubble collapse and the SFTs formation. Note that the current work only focuses on the case that the number ratio between He atoms and Al vacancies is 1:1.« less

Hartree-Fock limit values of multipole moments, polarizabilities, and hyperpolarizabilities for atoms and diatomic molecules

NASA Astrophysics Data System (ADS)

Kobus, Jacek

2015-02-01

Recently it has been demonstrated that the finite difference Hartree-Fock method can be used to deliver highly accurate values of electric multipole moments together with polarizabilities αz z,Az ,z z , and hyperpolarizabilities βz z z, γz z z,Bz z ,z z , for the ground states of various atomic and diatomic systems. Since these results can be regarded as de facto Hartree-Fock limit values their quality is of the utmost importance. This paper reexamines the use of the finite field method to calculate these electric properties, discusses its accuracy, and presents an updated list of the properties for the following atoms and diatomic molecules: H-, He, Li, Li+,Li2 +,Li-,Be2 + , Be, B+,C2 + , Ne, Mg2 +, Mg, Al+,Si2 + , Ar, K+,Ca2 +,Rb+,Sr2 +,Zr4 +,He2 , Be2,N2,F2,O2 , HeNe, LiH2 +, LiCl, LiBr, BH, CO, FH, NaCl, and KF. The potential energy curves and the dependence of the electric properties on the internuclear distance is also studied for He2,LiH+,Be2 , and HeNe systems.

Association between proton pump inhibitors and hepatic encephalopathy

PubMed Central

Bian, Jin; Wang, Anqiang; Lin, Jianzhen; Wu, Liangcai; Huang, Hanchun; Wang, Shanshan; Yang, Xiaobo; Lu, Xin; Xu, Yiyao; Zhao, Haitao

2017-01-01

Abstract Background & aims: Several studies have shown that proton pump inhibitors (PPIs) use can increase the risk of developing hepatic encephalopathy (HE) in patients with liver dysfunction. However, no definite conclusion is drawn because of study design limitations. Therefore, we conducted a meta-analysis to explore the association between PPIs and HE. Methods: We searched PubMed, EMBASE, and the Cochrane Library from inception until November 2016. Data from the identified studies were combined using a random effects model, and odds ratios (ORs) were calculated. Results: Three case-control studies were included. Compared with nonusers, hepatic insufficiency patients receiving PPIs therapy had a significantly increased risk of developing HE (OR = 1.76, 95% CI: 1.15–2.69), with notable heterogeneity (I2 = 61.4%, P = .075) and publication bias. No relevance was found between PPIs and HE after using the trim and fill method (OR = 1.360, 95%CI: 0.909–2.035, P = .135). Conclusions: PPIs are associated with a higher risk of HE among patients with chronic and acute liver dysfunction. A final conclusion cannot be drawn because of the limited number of studies and a lack of prospective studies. PMID:28445288

The question of sign-language and the utility of signs in the instruction of the deaf: two papers by Alexander Graham Bell (1898).

PubMed

Bell, Alexander Graham

2005-01-01

Alexander Graham Bell is often portrayed as either hero or villain of deaf individuals and the Deaf community. His writings, however, indicate that he was neither, and was not as clearly definite in his beliefs about language as is often supposed. The following two articles, reprinted from The Educator (1898), Vol. V, pp. 3-4 and pp. 38-44, capture Bell's thinking about sign language and its use in the classroom. Contrary to frequent claims, Bell does not demand "oral" training for all deaf children--even if he thinks it is the superior alternative--but does advocate for it for "the semi-deaf" and "the semi-mute." "In regard to the others," he writes, "I am not so sure." Although he clearly voices his support for oral methods and fingerspelling (the Rochester method) over sign language, Bell acknowledges the use and utility of signing in a carefully-crafted discussion that includes both linguistics and educational philosophy. In separating the language used at home from that in school and on the playground, Bell reveals a far more complex view of language learning by deaf children than he is often granted. (M. Marschark).

Synthesis of FeCoB amorphous nanoparticles and application in ferrofluids

NASA Astrophysics Data System (ADS)

Zhao, Shuchun; Bian, Xiufang; Yang, Chuncheng; Yu, Mengchun; Wang, Tianqi

2018-03-01

Magnetic FeCoB amorphous nanoparticles were successfully synthesized by borohydride reduction in water/n-hexane (W/He) microemulsions. The as-prepared FeCoB alloys are amorphous and spherical nanoparticles with an average particle size about 10.7 nm, compared to FeCoB alloys with an average particle size about 304.2 nm which were synthesized by a conventional aqua-solution method. Furthermore, three kinds of FeCoB ferrofluids (FFs) were prepared by dispersing FeCoB particles into W/He microemulsion, water and silicone oil respectively. Results show that the W/He-based FeCoB FFs are superparamagnetic with saturation magnetization (Ms) reaching to 12.4 emu/g. Besides, compared to water-based and silicone oil-based FFs, W/He-based FeCoB FFs exhibit high stability, with magnetic weights decreasing slightly even under the magnetic field intensity of H = 210 mT. In the W/He-based FeCoB FFs, interfacial tensions of water phase and oil phase are supposed to prevent the agglomeration and sedimentation of FeCoB nanoparticles dispersed in different water droplets of the microemulsion, compared to the current stabilizing method of directly modifying the surface of particles.

Used fuel storage monitoring using novel 4He scintillation fast neutron detectors and neutron energy discrimination analysis

NASA Astrophysics Data System (ADS)

Kelley, Ryan P.

With an increasing quantity of spent nuclear fuel being stored at power plants across the United States, the demand exists for a new method of cask monitoring. Certifying these casks for transportation and long-term storage is a unique dilemma: their sealed nature lends added security, but at the cost of requiring non-invasive measurement techniques to verify their contents. This research will design and develop a new method of passively scanning spent fuel casks using 4He scintillation detectors to make this process more accurate. 4He detectors are a relatively new technological development whose full capabilities have not yet been exploited. These detectors take advantage of the high 4He cross section for elastic scattering at fast neutron energies, particularly the resonance around 1 MeV. If one of these elastic scattering interactions occurs within the detector, the 4He nucleus takes energy from the incident neutron, then de-excites by scintillation. Photomultiplier Tubes (PMTs) at either end of the detector tube convert this emitted light into an electrical signal. The goal of this research is to use the neutron spectroscopy features of 4He scintillation detectors to maintain accountability of spent fuel in storage. This project will support spent fuel safeguards and the detection of fissile material, in order to minimize the risk of nuclear proliferation and terrorism.

First-principles modeling of quantum nuclear effects and atomic interactions in solid 4He at high pressure

NASA Astrophysics Data System (ADS)

Cazorla, Claudio; Boronat, Jordi

2015-01-01

We present a first-principles computational study of solid 4He at T =0 K and pressures up to ˜160 GPa. Our computational strategy consists in using van der Waals density functional theory (DFT-vdW) to describe the electronic degrees of freedom in this material, and the diffusion Monte Carlo (DMC) method to solve the Schrödinger equation describing the behavior of the quantum nuclei. For this, we construct an analytical interaction function based on the pairwise Aziz potential that closely matches the volume variation of the cohesive energy calculated with DFT-vdW in dense helium. Interestingly, we find that the kinetic energy of solid 4He does not increase appreciably with compression for P ≥85 GPa. Also, we show that the Lindemann ratio in dense solid 4He amounts to 0.10 almost independently of pressure. The reliability of customary quasiharmonic DFT (QH DFT) approaches in describing quantum nuclear effects in solids is also studied. We find that QH DFT simulations, although provide a reasonable equation of state in agreement with experiments, are not able to reproduce correctly these critical effects in compressed 4He. In particular, we disclose huge discrepancies of at least ˜50 % in the calculated 4He kinetic energies using both the QH DFT and present DFT-DMC methods.

Pío del Río Hortega and the discovery of the oligodendrocytes

PubMed Central

Pérez-Cerdá, Fernando; Sánchez-Gómez, María Victoria; Matute, Carlos

2015-01-01

Pío del Río Hortega (1882–1945) discovered microglia and oligodendrocytes (OLGs), and after Ramón y Cajal, was the most prominent figure of the Spanish school of neurology. He began his scientific career with Nicolás Achúcarro from whom he learned the use of metallic impregnation techniques suitable to study non-neuronal cells. Later on, he joined Cajal’s laboratory. and Subsequently, he created his own group, where he continued to develop other innovative modifications of silver staining methods that revolutionized the study of glial cells a century ago. He was also interested in neuropathology and became a leading authority on Central Nervous System (CNS) tumors. In parallel to this clinical activity, del Río Hortega rendered the first systematic description of a major polymorphism present in a subtype of macroglial cells that he named as oligodendroglia and later OLGs. He established their ectodermal origin and suggested that they built the myelin sheath of CNS axons, just as Schwann cells did in the periphery. Notably, he also suggested the trophic role of OLGs for neuronal functionality, an idea that has been substantiated in the last few years. Del Río Hortega became internationally recognized and established an important neurohistological school with outstanding pupils from Spain and abroad, which nearly disappeared after his exile due to the Spanish civil war. Yet, the difficulty of metal impregnation methods and their variability in results, delayed for some decades the confirmation of his great insights into oligodendrocyte biology until the development of electron microscopy and immunohistochemistry. This review aims at summarizing the pioneer and essential contributions of del Río Hortega to the current knowledge of oligodendrocyte structure and function, and to provide a hint of the scientific personality of this extraordinary and insufficiently recognized man. PMID:26217196

Structure of the exotic 9He nucleus from the no-core shell model with continuum

NASA Astrophysics Data System (ADS)

Vorabbi, Matteo; Calci, Angelo; Navrátil, Petr; Kruse, Michael K. G.; Quaglioni, Sofia; Hupin, Guillaume

2018-03-01

Background: The exotic 9He nucleus, which presents one of the most extreme neutron-to-proton ratios, belongs to the N =7 isotonic chain famous for the phenomenon of ground-state parity inversion with decreasing number of protons. Consequently, it would be expected to have an unnatural (positive) parity ground state similar to 11Be and 10Li. Despite many experimental and theoretical investigations, its structure remains uncertain. Apart from the fact that it is unbound, other properties including the spin and parity of its ground state, and the very existence of additional low-lying resonances are still a matter of debate. Purpose: In this work, we study the properties of 9He by analyzing the n +8He continuum in the context of the ab initio no-core shell model with continuum (NCSMC) formalism with chiral nucleon-nucleon interactions as the only input. Methods: The NCSMC is a state-of-the-art approach for the ab initio description of light nuclei. With its capability to predict properties of bound states, resonances, and scattering states in a unified framework, the method is particularly well suited for the study of unbound nuclei such as 9He. Results: Our analysis produces an unbound 9He nucleus. Two resonant states are found at the energies of ˜1 and ˜3.5 MeV, respectively, above the n +8He breakup threshold. The first state has a spin-parity assignment of Jπ=1/2 - and can be associated with the ground state of 9He, while the second, broader state has a spin parity of 3/2 -. No resonance is found in the 1/2 + channel, only a very weak attraction. Conclusions: We find that the 9He ground-state resonance has a negative parity and thus breaks the parity-inversion mechanism found in the 11Be and 10Li nuclei of the same N =7 isotonic chain.

D-Wave Electron-H, -He+, and -Li2+ Elastic Scattering and Photoabsorption in P States of Two-Electron Systems

NASA Technical Reports Server (NTRS)

Bhatia, A. K.

2014-01-01

In previous papers [A. K. Bhatia, Phys. Rev. A 85, 052708 (2012); 86, 032709 (2012); 87, 042705 (2013)] electron-H, -He+, and -Li2+ P-wave scattering phase shifts were calculated using the variational polarized orbital theory. This method is now extended to the singlet and triplet D-wave scattering in the elastic region. The long-range correlations are included in the Schrodinger equation by using the method of polarized orbitals variationally. Phase shifts are compared to those obtained by other methods. The present calculation provides results which are rigorous lower bonds to the exact phase shifts. Using the presently calculated D-wave and previously calculated S-wave continuum functions, photoionization of singlet and triplet P states of He and Li+ are also calculated, along with the radiative recombination rate coefficients at various electron temperatures.

The fabrication of magnetic particle-based chemiluminescence immunoassay for human epididymis protein-4 detection in ovarian cancer.

PubMed

Fu, Xiaoling; Liu, Yangyang; Qiu, Ruiyun; Foda, Mohamed F; Zhang, Yong; Wang, Tao; Li, Jinshan

2018-03-01

The magnetic particles have a significant influence on the immunoassay detection and cancer therapy. Herein, the chemiluminescence immunoassay combined with the magnetic particles (MPCLIA) was presented for the clinical determination and analysis of human epididymis protein 4 (HE4) in the human serum. Under the optimized experiment conditions, the secure MPCLIA method can detect HE4 in the broader range of 0-1000 pmol/L, with a lower detection limit of 1.35 pmol/L. The satisfactory recovery rate of the method in the serum ranged from 83.62% to 105.10%, which was well within the requirement of clinical analysis. Moreover, the results showed the good correlation with enzyme-linked immunosorbent assay (ELISA), with the correlation coefficient of 0.9589. This proposed method has been successfully applied to the clinical determination of HE4 in the human serum.

[Here the world is burning: the 70th anniversary of the death of neurologist Dr. John Rittmeister].

PubMed

Teller, Ch

2013-09-01

John Rittmeister was a German neurologist (1898-1943) who was executed in Berlin-Plötzensee because of his decision to support organized political resistance against National Socialism. He grew up in a socially and materially privileged environment and following his final school examinations (Abitur) in 1917 he volunteered for war duties despite limited physical capabilities and was posted as a private to the war front in the Italian Alps and the Champagne district. While he was there he made his first social experiences outside his original surroundings. After the war he studied medicine and following the final state examinations and graduation he progressed to specialist training as a neurologist in Munich. At this time he came into contact with C.G. Jung. During a study period in London in 1929 he worked for several weeks as a resident at Toynbee Hall, a university institution in Whitechapel and experienced the methods of community work used there which were known under the term settlement movement. He continued his specialist activities in the neurological clinic in Zürich founded by C. von Monakow. Following the experiences in London he broke up with C.G. Jung and turned to Sigmund Freud and therapeutic analysis under Gustav Bally. In 1937 he returned to Germany. In 1939 he became director of the Policlinic of the German Institute for Psychological Research and Psychotherapy. Probably also due to his own war experiences in 1941/1942 he participated in the drafting of a flyer for the Schulze-Boysen/Harnack group against the war and after 8 months in prison he was executed in Berlin on 13 May 1943.

Game of Life Music

NASA Astrophysics Data System (ADS)

Miranda, Eduardo R.; Kirke, Alexis

At the time when the first author was post-graduate student, in the evenings he used to entertain himself with the equipment in the electronic music studio at the University of York until dawn. It must have been around three o'clock in the morning of a rather cold winter night in the late 1980s, when he connected his Atari 1040ST computer to a synthesizer to test the first prototype of a system, which he was developing for his thesis. The system, named CAMUS (short for Cellular Automata Music), implemented a method that he invented to render music from the behaviour of the Game of Life (GoL) cellular automata (CA).

About 3He Ions Predominant Acceleration During the January 20, 2005 Solar Flare

NASA Astrophysics Data System (ADS)

Troitskaya, E. V.; Arkhangelskaja, I. V.; Arkhangelskiy, A. I.

We have studied some properties of the powerful solar flare of January 20, 2005 by methods of nuclear lines analysis. The results of temporal profiles investigation in corresponding to neutron capture energy bands allow the supposition about predominant acceleration of 3He ions in the corona, their subsequent propagation to the low chromosphere and the photosphere where the area of 2.223 MeV γ-line effective productions is located. The characteristics of accelerated 3He ions propagation processes and the basic explanation of observable properties of this solar flare due to the variations of 3He content are discussed in the presented article.

Estimation of d- 2 H Breakup Neutron Energy Distributions From d- 3 He

DOE PAGES

Hoop, B.; Grimes, S. M.; Drosg, M.

2017-06-19

A method is described to estimate deuteron-on-deuteron breakup neutron distributions at 0° using deuterium bombardment of 3He. Break-up neutron distributions are modeled with the product of a Fermi-Dirac distribution and a cumulative logistic distribution function. Four measured break-up neutron distributions from 6.15- to 12.0-MeV deuterons on 3He are compared with thirteen measured distributions from 6.83- to 11.03-MeV deuterons on deuterium. Model pararmeters that describe d -3He neutron distributions are used to estimate neutron distributions from 6- to 12-MeV deuterons on deuterium.

Helium in supernova remnants

NASA Astrophysics Data System (ADS)

Danziger, I. J.; Leibowitz, E.

1983-02-01

Observational data for supernova remnants (SNR) which exhibit He abundances exceeding the normal value of 0.10 are examingd. Attention is given to the Crab, Cas A, and Puppis A nebular O, N, and He abundances, sizes, and ages. The overabundances of He and N detected in the Crab and Cas A nebulae are suggested to have arisen from swept-up interstellar matter. Therefore, the He abundances in interstellar matter may be calculated from data on old SNR. However, the Larger and Smaller Magellanic clouds display lowered abundances, which may be due to stratification caused by ionization. The method is useful for SNRs located within 5 mpc of the local group of galaxies.

Terrestrial cosmogenic 3He: where are we 30 years after its discovery?

NASA Astrophysics Data System (ADS)

Blard, Pierre-Henri; Pik, Raphaël; Farley, Kenneth A.; Lavé, Jérôme; Marrocchi, Yves

2016-04-01

It is now 30 years since cosmogenic 3He has been detected for the first time in a terrestrial sample (Kurz, 1986). 3He is now a widely used geochemical tool in many fields of Earth sciences: volcanology, tectonics, paleoclimatology. 3He has the advantage to have a high "production rate" to "detection limit" ratio, allowing surfaces as young as hundred of years to be dated. Although its nuclear stability implies several limitations, it moreover represents a useful alternative to 10Be in mafic environments. This contribution is a review of the progresses that have been accomplished since this discovery, and discuss strategies to improve both the accuracy and the precision of this geochronometer. 1) Measurement of cosmogenic 3He Correction of magmatic 3He. To estimate the non-cosmogenic magmatic 3He, Kurz (1986) invented a two steps method involving crushing of phenocrysts (to analyze the isotopic ratio of the magmatic component), followed by a subsequent melting of the sample, to extract the remaining components, including the cosmogenic 3He: 3Hec = 3Hemelt -4Hemelt x (3He/4He)magmatic (1) Several studies suggested that the preliminary crushing may induce a loss of cosmogenic 3He (Hilton et al., 1993; Yokochi et al., 2005; Blard et al., 2006), implying an underestimate of the cosmogenic 3He measurement. However, subsequent work did not replicate these observations (Blard et al., 2008; Goerhing et al., 2010), suggesting an influence of the used apparatus. An isochron method (by directly melting several phenocrysts aliquots) is an alternative to avoid the preliminary crushing step (Blard and Pik, 2008). Atmospheric contamination. Protin et al. (in press) provides robust evidences for a large and irreversible contamination of atmospheric helium on silicate surfaces. This unexpected behavior may reconcile the contrasted observations about the amplitude of crushing loss. This undesirable atmospheric contamination is negligible if grain fractions smaller than 150 mm are removed before melting. Correction of radiogenic 4He and nucleogenic 3He. Equation 1 is valid only if the 4He extracted by melting is entirely magmatic. To account for a possible radiogenic 4He component, it is crucial to properly estimate the radiogenic 4He production rate, by measuring the U, Th and Sm concentrations of both phenocryst and host, and the phenocryst size. Estimating the nucleogenic 3He also requires measuring Li in the phenocryst. Accuracy of analytical systems. A recent inter-laboratory comparison involving 6 different groups indicated systematic offsets between labs (up to 7%) (Blard et al., 2015). Efforts must be pursued to remove these inaccuracies. 2) Production rates Absolute calibration. There are 25 3He calibration sites among the world, from -47° S to 64° N in latitude, and from 35 to 3800 m in elevation. After scaling these production rates to sea level high latitude, this dataset reveals a significant statistical dispersion (ca. 13%). Efforts should be focused on regions that are free of data and others, such as the Eastern Atlantic that yields values systematically off. 3He/10Be cross calibrations. Some studies (Gayer et al., 2004 ; Amidon et al., 2009) identified an altitude dependence of the 3He/10Be production ratio in the Himalayas, while other data from the Andes and Africa did not (Blard et al., 2013b ; Schimmelpfennig et al., 2011). There is thus a crucial need for new data at high and low elevation, with and without snow, to precisely quantify the cosmogenic thermal neutron production. Artificial target experiments may also be useful.

Causal Interpretations of Psychological Attributes

ERIC Educational Resources Information Center

Kane, Mike

2017-01-01

In the article "Rethinking Traditional Methods of Survey Validation" Andrew Maul describes a minimalist validation methodology for survey instruments, which he suggests is widely used in some areas of psychology and then critiques this methodology empirically and conceptually. He provides a reduction ad absurdum argument by showing that…

Establishing confidence in complex physics codes: Art or science?

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

Trucano, T.

1997-12-31

The ALEGRA shock wave physics code, currently under development at Sandia National Laboratories and partially supported by the US Advanced Strategic Computing Initiative (ASCI), is generic to a certain class of physics codes: large, multi-application, intended to support a broad user community on the latest generation of massively parallel supercomputer, and in a continual state of formal development. To say that the author has ``confidence`` in the results of ALEGRA is to say something different than that he believes that ALEGRA is ``predictive.`` It is the purpose of this talk to illustrate the distinction between these two concepts. The authormore » elects to perform this task in a somewhat historical manner. He will summarize certain older approaches to code validation. He views these methods as aiming to establish the predictive behavior of the code. These methods are distinguished by their emphasis on local information. He will conclude that these approaches are more art than science.« less

Quantitative electrophysiological monitoring of anti-histamine drug effects on live cells via reusable sensor platforms.

PubMed

Pham Ba, Viet Anh; Cho, Dong-Guk; Kim, Daesan; Yoo, Haneul; Ta, Van-Thao; Hong, Seunghun

2017-08-15

We demonstrated the quantitative electrophysiological monitoring of histamine and anti-histamine drug effects on live cells via reusable sensor platforms based on carbon nanotube transistors. This method enabled us to monitor the real-time electrophysiological responses of a single HeLa cell to histamine with different concentrations. The measured electrophysiological responses were attributed to the activity of histamine type 1 receptors on a HeLa cell membrane by histamine. Furthermore, the effects of anti-histamine drugs such as cetirizine or chlorphenamine on the electrophysiological activities of HeLa cells were also evaluated quantitatively. Significantly, we utilized only a single device to monitor the responses of multiple HeLa cells to each drug, which allowed us to quantitatively analyze the antihistamine drug effects on live cells without errors from the device-to-device variation in device characteristics. Such quantitative evaluation capability of our method would promise versatile applications such as drug screening and nanoscale bio sensor researches. Copyright © 2017 Elsevier B.V. All rights reserved.

A survey of membrane oxygenator heat-exchanger integrity testing at cardiac surgery centres in Great Britain and Ireland.

PubMed

Carlton, Matthew; Campbell, John

2013-11-01

Membrane oxygenator heat exchanger (HE) device failure is reported to be very low for both short- and long-term extracorporeal devices. All oxygenator manufacturers provide instructions for leak testing of their HE devices prior to patient use. In addition to these recommendations, since 2006 at Nottingham University Hospitals (NUH) we have also additionally pressure tested HE devices prior to use. We conducted a national survey of cardiac centers in Great Britain and Ireland to determine the methods undertaken in individual centers for validation of the integrity of HE devices. Furthermore, we also collected information on the routine maintenance techniques utilized within these centers to inhibit microbial growth in the water used in the heater-cooler units (HCUs). In total, 34 responses were collected from the 57 centers performing cardiac surgery, producing a response rate of 60%. Of the responding centers, 71% are adhering to manufacturer's recommended guidelines of circulating the water through the device for 5 minutes. Of these centers, 17% reported detecting a leak between the HE and membrane compartment of the oxygenator. In responding centers, 29% reported using the pressure test technique. In the centers utilizing pressure testing, 60% reported detecting a leak. This survey reports an association of a greater HE leak detection rate using the pressure test technique compared to using water testing in isolation (p = 0.034). We believe the pressure testing method provides the perfusionist with confidence in the integrity of the HE for short- and long-term circulatory support devices prior to use in both elective and emergency situations.

Two and three-dimensional segmentation of hyperpolarized 3He magnetic resonance imaging of pulmonary gas distribution

NASA Astrophysics Data System (ADS)

Heydarian, Mohammadreza; Kirby, Miranda; Wheatley, Andrew; Fenster, Aaron; Parraga, Grace

2012-03-01

A semi-automated method for generating hyperpolarized helium-3 (3He) measurements of individual slice (2D) or whole lung (3D) gas distribution was developed. 3He MRI functional images were segmented using two-dimensional (2D) and three-dimensional (3D) hierarchical K-means clustering of the 3He MRI signal and in addition a seeded region-growing algorithm was employed for segmentation of the 1H MRI thoracic cavity volume. 3He MRI pulmonary function measurements were generated following two-dimensional landmark-based non-rigid registration of the 3He and 1H pulmonary images. We applied this method to MRI of healthy subjects and subjects with chronic obstructive lung disease (COPD). The results of hierarchical K-means 2D and 3D segmentation were compared to an expert observer's manual segmentation results using linear regression, Pearson correlations and the Dice similarity coefficient. 2D hierarchical K-means segmentation of ventilation volume (VV) and ventilation defect volume (VDV) was strongly and significantly correlated with manual measurements (VV: r=0.98, p<.0001 VDV: r=0.97, p<.0001) and mean Dice coefficients were greater than 92% for all subjects. 3D hierarchical K-means segmentation of VV and VDV was also strongly and significantly correlated with manual measurements (VV: r=0.98, p<.0001 VDV: r=0.64, p<.0001) and the mean Dice coefficients were greater than 91% for all subjects. Both 2D and 3D semi-automated segmentation of 3He MRI gas distribution provides a way to generate novel pulmonary function measurements.

Elevated serum concentrations of HE4 as a novel biomarker of disease severity and renal fibrosis in kidney disease

PubMed Central

Liang, Jianbo; Yue, Caifeng; Wang, Fen; Song, Junli; Wang, Jianfeng; Liu, Min; Luo, Jinmei; Li, Laisheng

2016-01-01

Background Human epididymis protein 4 (HE4), has recently been reported as a mediator of renal fibrosis. However, serum HE4 levels appear in a large number of patient samples with chronic kidney disease (CKD), and the relationship of these levels to disease severity and renal fibrosis is unknown. Methods In 427 patients at different stages of CKD excluding gynecologic cancer and 173 healthy subjects, serum HE4 concentrations were tested by chemiluminescent microparticle immunoassay. Renal biopsy was performed on 259 of 427 subjects. Histological findings were evaluated using standard immunohistochemistry. Results The levels of serum HE4 were higher in CKD patients than in healthy subjects, and higher levels were associated with more severe CKD stages. Patients with more severe renal fibrosis tended to have higher HE4 levels, and correlation analysis showed a significant correlation between HE4 and degree of renal fibrosis (r = 0.938, P < 0.0001). HE4 can be a predictor of renal fibrosis in CKD patients; the area under the receiver-operating characteristic curve (AUC-ROC) was 0.99, higher than the AUC-ROC of serum creatinine (0.89). Conclusion Elevated levels of serum HE4 are associated with decreased kidney function, and also with an advanced stage of renal fibrosis, suggesting that HE4 may serve as a valuable clinical biomarker for renal fibrosis of CKD. PMID:27589683

Cross-checking groundwater age by 4He and 14C dating in a granite, Tono area, central Japan

NASA Astrophysics Data System (ADS)

Hasegawa, Takuma; Nakata, Kotaro; Tomioka, Yuichi; Goto, Kazuyuki; Kashiwaya, Koki; Hama, Katsuhiro; Iwatsuki, Teruki; Kunimaru, Takanori; Takeda, Masaki

2016-11-01

Groundwater dating was performed simultaneously by the 4He and 14C methods in granite of the Tono area in central Japan. Groundwater was sampled at 30 packed-off sections of six 1000-m boreholes. 4He concentrations increased and 14C concentrations decreased along a groundwater flow path on a topographic gradient. 4He ages were calculated by using the in situ 4He production rate derived from the porosity, density, and U and Th content of the rock, neglecting external flux. 14C ages were calculated with a noncorrected model in which the initial 14C content was 100 percent of the modern radiocarbon level (Co = 100 pmC), a statistical model using the average 14C content of tritium-bearing samples (Co = 46.4 pmC), and a δ13C model based on the isotopic mass balance. Although the absolute 14C ages calculated by the models were different, the relative 14C ages were almost identical. The relative 14C ages were considered reliable because dissolved inorganic carbon has no significant geochemical reactions in granite. The relation between the 4He ages and the noncorrected 14C ages was [4He age] = 1.15 [14C age] + 7200 (R2 = 0.81), except in the discharge area. The slope of this relation was equivalent to unity, which indicates that the 4He accumulation rate is confirmed by the relative 14C ages. Moreover, the accumulated 3He/4He ratio was equivalent to that derived from the 6Li(α,n)3H reaction in granite. These results show that the accumulated He is of crustal origin, produced in situ without external flux, except in the discharge area. The intercept value of 7200 a implies that the 14C concentrations were diluted due to geochemical reactions. Tritium-bearing samples supported this result. Simultaneous measurements make it feasible to estimate the accumulation rate of 4He and initial dilution of 14C, which cannot be done with a single method. Cross-checking groundwater dating has the potential to provide more reliable groundwater ages. The circulation time of the groundwater flow in the Tono area may be several tens of thousands of years, and the groundwater age calculated from the 4He and 14C ages appears to be consistent with geochemical information such as groundwater types, δD and δ18O.

Production of reactive species using vacuum ultraviolet photodissociation as a tool for studying their effects in plasma medicine: simulations and measurements

NASA Astrophysics Data System (ADS)

Ono, Ryo; Tokumitsu, Yusuke; Zen, Shungo; Yonemori, Seiya

2014-11-01

We propose a method for producing OH, H, O, O3, and O2(a1Δg) using the vacuum ultraviolet photodissociation of H2O and O2 as a tool for studying the reaction processes of plasma medicine. For photodissociation, an H2O/He or O2/He mixture flowing in a quartz tube is irradiated by a Xe2 or Kr2 excimer lamp. The effluent can be applied to a target. Simulations show that the Xe2 lamp method can produce OH radicals within 0.1-1 ppm in the effluent at 5 mm from a quartz tube nozzle. This is comparable to those produced by a helium atmospheric-pressure plasma jet (He-APPJ) currently used in plasma medicine. The Xe2 lamp method also produces H atoms of, at most, 6 ppm. In contrast, the maximum O densities produced by the Xe2 and Kr2 lamp methods are 0.15 ppm and 2.5 ppm, respectively; these are much lower than those from He-APPJ (several tens of ppm). Both lamp methods can produce ozone at concentrations above 1000 ppm and O2(a1Δg) at tens of ppm. The validity of the simulations is verified by measuring the O3 and OH densities produced by the Xe2 lamp method using ultraviolet absorption and laser-induced fluorescence. The differences between the measured and simulated densities for O3 and OH are 20% and factors of 3-4, respectively.

Digital enhancement of haematoxylin- and eosin-stained histological images for red-green colour-blind observers.

PubMed

Landini, G; Perryer, G

2009-06-01

Individuals with red-green colour-blindness (CB) commonly experience great difficulty differentiating between certain histological stain pairs, notably haematoxylin-eosin (H&E). The prevalence of red-green CB is high (6-10% of males), including among medical and laboratory personnel, and raises two major concerns: first, accessibility and equity issues during the education and training of individuals with this disability, and second, the likelihood of errors in critical tasks such as interpreting histological images. Here we show two methods to enhance images of H&E-stained samples so the differently stained tissues can be well discriminated by red-green CBs while remaining usable by people with normal vision. Method 1 involves rotating and stretching the range of H&E hues in the image to span the perceptual range of the CB observers. Method 2 digitally unmixes the original dyes using colour deconvolution into two separate images and repositions the information into hues that are more distinctly perceived. The benefits of these methods were tested in 36 volunteers with normal vision and 11 with red-green CB using a variety of H&E stained tissue sections paired with their enhanced versions. CB subjects reported they could better perceive the different stains using the enhanced images for 85% of preparations (method 1: 90%, method 2: 73%), compared to the H&E-stained original images. Many subjects with normal vision also preferred the enhanced images to the original H&E. The results suggest that these colour manipulations confer considerable advantage for those with red-green colour vision deficiency while not disadvantaging people with normal colour vision.

Vortices in rotating superfluid 3He.

PubMed

Lounasmaa, O V; Thuneberg, E

1999-07-06

In this review we first present an introduction to 3He and to the ROTA collaboration under which most of the knowledge on vortices in superfluid 3He has been obtained. In the physics part, we start from the exceptional properties of helium at millikelvin temperatures. The dilemma of rotating superfluids is presented. In 4He and in 3He-B the problem is solved by nucleating an array of singular vortex lines. Their experimental detection in 3He by NMR is described next. The vortex cores in 3He-B have two different structures, both of which have spontaneously broken symmetry. A spin-mass vortex has been identified as well. This object is characterized by a flow of spins around the vortex line, in addition to the usual mass current. A great variety of vortices exist in the A phase of 3He; they are either singular or continuous, and their structure can be a line or a sheet or fill the whole liquid. Altogether seven different types of vortices have been detected in 3He by NMR. We also describe briefly other experimental methods that have been used by ROTA scientists in studying vortices in 3He and some important results thus obtained. Finally, we discuss the possible applications of experiments and theory of 3He to particle physics and cosmology. In particular, we report on experiments where superfluid 3He-B was heated locally by absorption of single neutrons. The resulting events can be used to test theoretical models of the Big Bang at the beginning of our universe.

Vortices in rotating superfluid 3He

PubMed Central

Lounasmaa, Olli V.; Thuneberg, Erkki

1999-01-01

In this review we first present an introduction to 3He and to the ROTA collaboration under which most of the knowledge on vortices in superfluid 3He has been obtained. In the physics part, we start from the exceptional properties of helium at millikelvin temperatures. The dilemma of rotating superfluids is presented. In 4He and in 3He-B the problem is solved by nucleating an array of singular vortex lines. Their experimental detection in 3He by NMR is described next. The vortex cores in 3He-B have two different structures, both of which have spontaneously broken symmetry. A spin-mass vortex has been identified as well. This object is characterized by a flow of spins around the vortex line, in addition to the usual mass current. A great variety of vortices exist in the A phase of 3He; they are either singular or continuous, and their structure can be a line or a sheet or fill the whole liquid. Altogether seven different types of vortices have been detected in 3He by NMR. We also describe briefly other experimental methods that have been used by ROTA scientists in studying vortices in 3He and some important results thus obtained. Finally, we discuss the possible applications of experiments and theory of 3He to particle physics and cosmology. In particular, we report on experiments where superfluid 3He-B was heated locally by absorption of single neutrons. The resulting events can be used to test theoretical models of the Big Bang at the beginning of our universe. PMID:10393895

Stopping cross sections for 0.25-3.0-MeV He-4 ions in cadmium sulfide

NASA Technical Reports Server (NTRS)

Miller, W. E.; Hutchby, J. A.

1975-01-01

Stopping cross sections of He-4 ions with energies between 0.25 and 3.0 MeV have been measured for cadmium sulfide with a probable error of plus or minus 7% to 8%. The experimental method utilized the Rutherford backscattering technique and measured the energy loss of elastically scattered He-4 ions from films of cadmium sulfide sputtered on carbon substrates. The experimental data are compared with recent experimental and theoretical results.

Development and Evaluation of a Novel Method for Basic Marksmanship Training on an Australian Army Course

DTIC Science & Technology

2014-02-01

in DSTO’s Land Division. He holds a Bachelor of Science Degree and First Class Honours Degree in Psychology from the University of Adelaide. He...also holds a Master of Psychology Degree from the University of South Australia and is a Registered Psychologist in Australia. He joined DSTO in 2002...including LF6 qualification. There was no evidence of negative training associated with using different colour targets in the simulator and live-fire

Soft X-ray laser using pumping of 3P and 4P levels of He-like and H-like ions

DOEpatents

Hagelstein, Peter L.

1987-01-01

X-ray laser method and apparatus for producing coherent radiation at, for example, energies of at least 40 eV, using Be-like Cr, N-like Ni, He-like Na, B-like Cr, Be-like Mn or similar multiply ionized species to pump appropriate high energy transitions in He-like or H-like N, O, F, C or rare gases, with associated laser transition gains of 4-50 cm.sup.-1.

Soft x-ray laser using pumping of 3p and 4p levels of He-like and H-like ions

DOEpatents

Hagelstein, P.L.

1985-07-05

X-ray laser method and apparatus for producing coherent radiation at, for example, energies of at least 40 eV, using Be-like Cr, N-like Ni, He-like Na, B-like Cr, Be-like Mn or similar multiply ionized species to pump appropriate high energy transitions in He-like or H-like N, O, F, C or rare gases, with associated laser transition gains of 4 to 50 cm/sup -1/.

Soft x-ray laser using pumping of 3P and 4P levels of He-like and H-like ions

DOEpatents

Hagelstein, P.

1982-03-26

X-ray laser method and apparatus for producing coherent radiation at, for example, energies of 40 to 189 eV, using Be-like Cr, N-like Ni, He-like Na, B-like Cr, Be-like Mn or similar multiply ionized species to pump appropriate high energy transitions in He-like or H-like rare gases or N, O, F, or C gases, with associated laser transition gains of 20 to 50 cm/sup -1/.

[Hodge and his planes].

PubMed

van Gijn, Jan; Gijselhart, Joost P

2010-01-01

Hugh Lenox Hodge (1796-1873) was professor of obstetrics at the University of Pennsylvania for more than 25 years. He divided the birth canal into four virtual and parallel planes through pelvic protuberances, a method still widely used. He also developed a pessary that is now mainly used in stress incontinence.

"Quantum Interference with Slits" Revisited

ERIC Educational Resources Information Center

Rothman, Tony; Boughn, Stephen

2011-01-01

Marcella has presented a straightforward technique employing the Dirac formalism to calculate single- and double-slit interference patterns. He claims that no reference is made to classical optics or scattering theory and that his method therefore provides a purely quantum mechanical description of these experiments. He also presents his…

AEGIS and Ship Self-Defense System (SSDS) Platforms: Using KVA Analysis, Risk Simulation and Strategic Real Options to Assess Operational Effectiveness

DTIC Science & Technology

2007-04-30

numerous reengineering projects and developed a new objective method for objectively measuring the value-added by reengineering. His last assignment...in the corporate world was as the Chief of Consumer Market Research for Telecom Italia in Venice, Italy, where he developed new methods for ...predicting the adoption rates for new interactive multimedia broadband applications. He is Managing Partner for Business Process Auditors, a firm that

Lessons learned by (from?) an economist working in medical decision making.

PubMed

Wakker, Peter P

2008-01-01

This article is a personal account of the author's experiences as an economist working in medical decision making. He discusses the differences between economic decision theory and medical decision making and gives examples of the mutual benefits resulting from interactions. In particular, he discusses the pros and cons of different methods for measuring quality of life (or, as economists would call it, utility), including the standard gamble, the time tradeoff, and the healthy-years equivalent methods.

High-frequency heterodyne lock-in thermography (HeLIT): A highly sensitive method to detect early caries

NASA Astrophysics Data System (ADS)

Wang, Fei; Liu, Jun-yan; Yang, Jun-han; Oliullah, Md.; Wang, Xiao-chun; Wang, Yang

2016-10-01

In this letter, a nonlinear photothermal characteristic of dental tissues has been verified by photothermal radiometry at a given frequency with changing of the laser intensity. Subsequently, the high-frequency heterodyne lock-in thermography (HeLIT) scheme has been introduced to overcome shortages of the low infrared camera frame rate and the poor signal-noise ratio. The smooth surface tooth was artificially demineralized at a different time, and then it was detected by HeLIT, Results illustrated that the phase delay increases with the extension of the demineralized treatment time. The comparison experiments between HeLIT and the homodyne lock-in thermography for detecting artificial caries were carried out. Experimental results illustrated that the HeLIT has the merits of high sensitivity and specificity in detecting early caries.

[Edouard Kufferath (1853-1909), eminent figure of past gynaecology and obstetrics at the ULB (Université libre de Bruxelles)].

PubMed

Leroy, F; Kufferath, P

2010-01-01

Edouard Kufferath (1853-1909) came from a German family of musicians. He was appointed as professor of obstetrics for 20 years and was Rector of the ULB (Université libre de Bruxelles) in 1905-1906. He was the first in Belgium to apply strict aseptic rules in obstetrics and to obtain hence a drastic reduction of maternal and newborn mortalities consecutive to puerperal fever. He improved the technique of symphyseotomy and invented a new method of labour induction. The type of obstetrical forceps that he conceived was known by his name and remained widely used by obstetricians in Brussels during at least six decades before the diffusion of the Swedish vacuum extractor. The exceptional quality of Kufferath's teaching was unanimously recognized. He became also active as communal Counsellor of the City of Brussels. Unanimously admired and respected, he prematurely passed away from a tongue cancer at the age of 55 years, covered with official honours.

Interface properties of SiO2/GaN structures formed by chemical vapor deposition with remote oxygen plasma mixed with Ar or He

NASA Astrophysics Data System (ADS)

Truyen, Nguyen Xuan; Taoka, Noriyuki; Ohta, Akio; Makihara, Katsunori; Yamada, Hisashi; Takahashi, Tokio; Ikeda, Mitsuhisa; Shimizu, Mitsuaki; Miyazaki, Seiichi

2018-06-01

The impacts of noble gas species (Ar and He) on the formation of a SiO2/GaN structure formed by a remote oxygen plasma-enhanced chemical vapor deposition (ROPE-CVD) method were systematically investigated. Atomic force microscopy revealed that ROPE-CVD with He leads to a smooth SiO2 surface compared with the case of Ar. We found that no obvious oxidations of the GaN surfaces after the SiO2 depositions with the both Ar and He cases were observed. The capacitance–voltage (C–V) curves of the GaN MOS capacitors formed by ROPE-CVD with the Ar and He dilutions show good interface properties with no hysteresis and good agreement with the ideal C–V curves even after post deposition annealing at 800 °C. Besides, we found that the current density–oxide electric field characteristics shows a gate leakage current for the Ar case lower than the He case.

Creating Energy.

ERIC Educational Resources Information Center

Wilson, David A.

The author of this booklet is an engineer who conducts experiments in solar energy. Here he has described basic principles of the field. He also details methods of constructing a variety of solar implements, including solar panels, solar cells, a concentrating collector and a solar furnace. The book is intended for the layman and contains…

The Role of Method in Teaching: An Informal Exploration.

ERIC Educational Resources Information Center

Sylwester, Robert

This bulletin discusses the following four important aspects of the teaching process: surface communication, and enactive, iconic, and symbolic representations of reality. The author begins with a discussion of surface communication in which he explains that our skin constitutes a barrier to communication. He states that we must, therefore, devise…

NITROGEN BOUNDING STUDY: METHODS FOR ESTIMATING THE RELATIVE EFFECTS OF SULFUR AND NITROGEN DEPOSITION ON SURFACE WATER CHEMISTRY

EPA Science Inventory

The leaching of atmospherically deposited nitrogen from forested watersheds may acidify lakes and streams. he Nitrogen Bounding Study evaluates the potential range of such adverse effects. he study estimates bounds on changes in regional-scale surface water acidification that mig...

Eric Kozubal | NREL

Science.gov Websites

researches new methods and technologies for energy-efficient air conditioning systems. He has tested more -6155 Eric joined NREL in 2002 and is a member of the Commercial Buildings Research Group. Eric recommendations. He uses tools such as CAD, Matlab, Engineer Equation Solver, Excel, and statistical software to

Developing Legal Problem-Solving Skills.

ERIC Educational Resources Information Center

Nathanson, Stephen

1994-01-01

A law professor explains how he came to view legal problem solving as the driving concept in law school curriculum design and draws on personal experience and a survey of students concerning teaching methods in a commercial law course. He outlines six curriculum design principles for teaching legal problem solving. (MSE)

Research Review

ERIC Educational Resources Information Center

Serig, Dan

2011-01-01

In this review, the author explores an often-used process in research--the mind map. He uses this method in his own research and artwork. He also uses this extensively with students, particularly master students when they are trying to surround issues in their thesis projects. Mind maps are closely associated with brainstorming, as brainstorming…

Life History and Identity

ERIC Educational Resources Information Center

Tierney, William G.

2013-01-01

This article uses the life history method to chronicle the challenges of a low-income, first-generation student en route to college. The paper addresses three questions: how Manuel navigates college and related topics such as roommates, family, and money; how he creates social networks; and how he works with adults such as teachers and…

Innovations: Scientific, Technological, and Social.

ERIC Educational Resources Information Center

Gabor, Dennis

Dr. Gabor, the inventor of holography (lenseless photography), defines "innovation" as a methodical creation of the human spirit, a novelty that once created can be usefully and repeatedly applied. He describes and evaluates 100 important technological and biological inventions that can probably be expected within the next 50 years. He also…

FROM THE HISTORY OF PHYSICS: Georgii L'vovich Shnirman: designer of fast-response instruments

NASA Astrophysics Data System (ADS)

Bashilov, I. P.

1994-07-01

A biography is given of the outstanding Russian scientist Georgii L'vovich Shnirman, whose scientific life had been 'top secret'. He was an experimental physicist and instrument designer, the founder of many branches of the Soviet instrument-making industry, the originator of a theory of electric methods of integration and differentiation, a theory of astasisation of pendulums, and also of original measurement methods. He was the originator and designer of automatic systems for the control of the measuring apparatus used at nuclear test sites and of automatic seismic station systems employed in monitoring nuclear tests. He also designed the first loop oscilloscopes in the Soviet Union, high-speed photographic and cine cameras (streak cameras, etc.), and many other unique instruments, including some mounted on moving objects.

Relevance of some of the theories of Ibn Khaldoun in his "Al Muqaddimah" to contemporary medicine. A personal interpretation.

PubMed

Al-Khader, Abdulla A

2002-11-01

The subjects in this paper include Ibn Khaldoun's thoughts on writing, and their implications on today's medical writing. This paper discusses why people write, plagiarism, "Original" and "Copied' writings and where history writing goes wrong and how this can be applied to Medical writing today. The paper also discusses the nature of Science and Knowledge as viewed by Ibn Khaldoun, the anatomy of intelligence, types of thought processes, and effects of environment and craftsmanship on intellect. Ibn Khaldoun's definition of the "Medical" profession and its social standing is discussed as well as his emphasis of the importance of exercise, diet and climate on healthy living. Ibn Khaldoun has clear and advanced concepts on education and methodology of education. He emphasizes 3 stages of coaching, and the importance of travel in consolidating and clarifying knowledge attainment. He abhors coercion as a method of educating the young. Developing the interest of the pupil in the art he is studying, is thought by Ibn Khaldoun to be the central theme of good education. Relevance of all this to contemporary medical education is discussed. Ibn Khaldoun has fascinating ahead-of-time views on the influence of peer pressure and what is now known as "Emotional Intelligence" and he rejects the idea that intelligence is ethnically determined. Instead, he emphasizes the environmental, social and craftsmanship influence on human behavior. He stresses that the method of education has a lot to do with the "apparent" intelligence or "stupidity" of pupils.

Screening apatites for (U-Th)/He thermochronometry via continuous ramped heating: He age components and implications for age dispersion

NASA Astrophysics Data System (ADS)

McDannell, Kalin T.; Zeitler, Peter K.; Janes, Darwin G.; Idleman, Bruce D.; Fayon, Annia K.

2018-02-01

Old slowly-cooled apatites often yield dispersed (U-Th)/He ages for a variety of reasons, some well understood and some not. Analytical protocols like careful grain selection can reduce the impact of this dispersion but add costs in time and resources and too often have proven insufficient. We assess a new analytical protocol that utilizes static-gas measurement during continuous ramped heating (CRH) as a means to rapidly screen apatite samples. In about the time required for a conventional total-gas analysis, this method can discriminate between samples showing expected volume-diffusion behavior and those showing anomalous release patterns inconsistent with their direct use in thermochronologic applications. This method also appears able to discriminate between the radiogenic and extraneous 4He fractions released by a sample, potentially allowing ages to be corrected. Well-behaved examples such as the Durango standard and other apatites with good age reproducibility show the expected smooth, sigmoidal gas-release curves predicted for volume diffusion using typical apatite kinetics, with complete exhaustion by ∼900 °C for linear heating at 20 °C/min. Secondary factors such as U and Th zoning and alpha-loss distribution have a relatively minor impact on such profiles. In contrast, samples having greater age dispersion show significant He release in the form of outgassing spikes and He release deferred to higher temperatures. Screening results for a range of samples permit us to assess the degree to which CRH screening can identify misbehaving grains, give insight into the source of extraneous He, and suggest that in some cases it may be possible to correct ages for the presence of such components.

Quantitative assessment of hepatic fibrosis in chronic hepatitis B and C: T1 mapping on Gd-EOB-DTPA-enhanced liver magnetic resonance imaging.

PubMed

Pan, Shen; Wang, Xiao-Qi; Guo, Qi-Yong

2018-05-14

To assess the accuracy of Look-Locker on gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) for staging liver fibrosis in chronic hepatitis B/C (CHB/C). We prospectively included 109 patients with CHB or CHC who underwent a 3.0-Tesla MRI examination, including T1-weighted and Look-Locker sequences for T1 mapping. Hepatocyte fractions (HeF) and relaxation time reduction rate (RE) were measured for staging liver fibrosis. A receiver operating characteristic analysis using the area under the receiver operating characteristic curve (AUC) was used to compare the diagnostic performance in predicting liver fibrosis between HeF and RE. A total of 73 patients had both pathological results and MRI information. The number of patients in each fibrosis stage was evaluated semiquantitatively according to the METAVIR scoring system: F0, n = 23 (31.5%); F1, n = 19 (26.0%); F2, n = 13 (17.8%); F3, n = 6 (8.2%), and F4, n = 12 (16.4%). HeF by EOB enhancement imaging was significantly correlated with fibrosis stage ( r = -0.808, P < 0.05). AUC values for diagnosis of any (≥ F1), significant (≥ F2) or advanced (≥ F3) fibrosis, and cirrhosis (F4) using HeF were 0.837 (0.733-0.913), 0.890 (0.795-0.951), 0.957 (0.881-0.990), and 0.957 (0.882-0.991), respectively. HeF measurement was more accurate than use of RE in establishing liver fibrosis staging, suggesting that calculation of HeF is a superior noninvasive liver fibrosis staging method. A T1 mapping-based HeF method is an efficient diagnostic tool for the staging of liver fibrosis.

A mixed-methods exploration of implementation of a comprehensive school healthy eating model one year after scale-up.

PubMed

Naylor, Patti-Jean; McKay, Heather A; Valente, Maria; Mâsse, Louise C

2016-04-01

To study the implementation of a school-based healthy eating (HE) model one year after scale-up in British Columbia (BC). Specifically, to examine implementation of Action Schools! BC (AS! BC) and its influence on implementation of classroom HE activities, and to explore factors associated with implementation. Diffusion of Innovations, Social Cognitive and Organizational Change theories guided our approach. We used a mixed-methods research design including focus group interviews (seven schools, sixty-two implementers) and a cross-sectional multistage survey to principals (n 36, 92 % response rate) and teachers of grades 4 to 7 (n 168, 70 % response rate). Self-reported implementation of classroom HE activities and reported use of specific AS! BC HE activities were primary implementation measures. Thematic analysis of focus group data and multilevel mixed-effect logistic regression analyses of survey data were conducted. Elementary schools across BC, Canada. Thirty-nine school districts, thirty-six principals, 168 grade 4 to 7 teachers. Forty-two per cent of teachers in registered schools were implementing AS! BC HE in their classrooms. Users were 6·25 times more likely to have delivered a HE lesson in the past week. Implementation facilitators were school champions, technical support and access to resources; barriers were lack of time, loss of leadership or momentum. Implementation predictors were teacher training, self-efficacy, experience with the physical activity component of AS! BC, supportive school climate and parental post-secondary education. Our findings reinforce that continued teacher training and support are important public health investments that contribute to successful implementation of school-based HE models after scale-up.

Nicotinamide induces mitochondrial-mediated apoptosis through oxidative stress in human cervical cancer HeLa cells.

PubMed

Feng, Yi; Wang, Yonghua; Jiang, Chengrui; Fang, Zishui; Zhang, Zhiqiang; Lin, Xiaoying; Sun, Liwei; Jiang, Weiying

2017-07-15

Nicotinamide participates in energy metabolism and influences cellular redox status and modulates multiple pathways related with both cellular survival and death. Recent studies have shown that it induced proliferation inhibition and apoptosis in many cancer cells. However, little is known about the effects of nicotinamide on human cervical cancer cells. We aimed to evaluate the effects of the indicated concentrations nicotinamide on cell proliferation, apoptosis and redox-related parameters in HeLa cells and investigated the apoptotic mechanism. After the treatment of the indicated concentrations nicotinamide, HeLa cell proliferation was evaluated by the CCK-8 assay and the production of ROS (reactive oxygen species) was measured using 2',7'-Dichlorofluorescin diacetate. The apoptotic effect was confirmed by observing the cellular and nuclear morphologies with fluorescence microscope and apoptotic rate of HeLa cell apoptosis was measured by flow cytometry using Annexin-V method. Moreover, we examined the mitochondrial membrane potential by JC-1 method and measured the expression of apoptosis related genes using qRT-PCR and immunoblotting. Nicotinamide restrained the HeLa cell proliferation and significantly increased the accumulation of ROS and depletion of GSH at relatively high concentrations. Furthermore, nicotinamide promoted HeLa cell apoptosis via the intrinsic mitochondrial apoptotic pathway. Our study revealed that nicotinamide induced the apoptosis through oxidative stress and intrinsic mitochondrial apoptotic pathways in HeLa cell. The results emerge that nicotinamide may be an inexpensive, safe and promising therapeutic agent or a neoadjuvant chemotherapy for cervical cancer patients, as well useful to find new drugs for cervical cancer therapy. Copyright © 2017 Elsevier Inc. All rights reserved.

On the molecular interaction between lactoferrin and the dye Red HE-3B. A novel approach for docking a charged and highly flexible molecule to protein surfaces

NASA Astrophysics Data System (ADS)

Grasselli, Mariano; Cascone, Osvaldo; Anspach, F. Birger; Delfino, Jose M.

2002-12-01

Lactoferrin (Lf) is a non-heme, iron binding protein present in many physiological fluids of vertebrates where its main role is the microbicidal activity. It has been isolated by different methods, including dye-affinity chromatography. Red HE-3B is one of the most common triazinic dyes applied in protein purification, but scant knowledge is available on structural details and on the energetics of its interaction with proteins. In this work we present a computational approach useful for identifying possible binding sites for Red HE-3B in apo and holo forms of Lfs from human and bovine source. A new geometrical description of Red HE-3B is introduced which greatly simplifies the conformational analysis. This approach proved to be of particular advantage for addressing conformational ensembles of highly flexible molecules. Predictions from this analysis were correlated with experimentally observed dye-binding sites, as mapped by protection from proteolysis in Red HE-3B/Lf complexes. This method could bear relevance for the screening of possible dye-binding sites in proteins whose structure is known and as a potential tool for the design of engineered protein variants which could be purified by dye-affinity chromatography.

On the molecular interaction between lactoferrin and the dye Red HE-3b. A novel approach for docking a charged and highly flexible molecule to protein surfaces.

PubMed

Grasselli, Mariano; Cascone, Osvaldo; Birger Anspach, F; Delfino, Jose M

2002-12-01

Lactoferrin (Lf) is a non-heme, iron binding protein present in many physiological fluids of vertebrates where its main role is the microbicidal activity. It has been isolated by different methods, including dye-affinity chromatography. Red HE-3B is one of the most common triazinic dyes applied in protein purification, but scant knowledge is available on structural details and on the energetics of its interaction with proteins. In this work we present a computational approach useful for identifying possible binding sites for Red HE-3B in apo and holo forms of Lfs from human and bovine source. A new geometrical description of Red HE-3B is introduced which greatly simplifies the conformational analysis. This approach proved to be of particular advantage for addressing conformational ensembles of highly flexible molecules. Predictions from this analysis were correlated with experimentally observed dye-binding sites, as mapped by protection from proteolysis in Red HE-3B/Lf complexes. This method could bear relevance for the screening of possible dye-binding sites in proteins whose structure is known and as a potential tool for the design of engineered protein variants which could be purified by dye-affinity chromatography.

In situ polarized 3He system for the Magnetism Reflectometer at the Spallation Neutron Source.

PubMed

Tong, X; Jiang, C Y; Lauter, V; Ambaye, H; Brown, D; Crow, L; Gentile, T R; Goyette, R; Lee, W T; Parizzi, A; Robertson, J L

2012-07-01

We report on the in situ polarized (3)He neutron polarization analyzer developed for the time-of-flight Magnetism Reflectometer at the Spallation Neutron Source at Oak Ridge National Laboratory. Using the spin exchange optical pumping method, we achieved a (3)He polarization of 76% ± 1% and maintained it for the entire three-day duration of the test experiment. Based on transmission measurements with unpolarized neutrons, we show that the average analyzing efficiency of the (3)He system is 98% for the neutron wavelength band of 2-5 Å. Using a highly polarized incident neutron beam produced by a supermirror bender polarizer, we obtained a flipping ratio of >100 with a transmission of 25% for polarized neutrons, averaged over the wavelength band of 2-5 Å. After the cell was depolarized for transmission measurements, it was reproducibly polarized and this performance was maintained for three weeks. A high quality polarization analysis experiment was performed on a reference sample of Fe/Cr multilayer with strong spin-flip off-specular scattering. Using a combination of the position sensitive detector, time-of-flight method, and the excellent parameters of the (3)He cell, the polarization analysis of the two-dimensional maps of reflected, refracted, and off-specular scattered intensity above and below the horizon were obtained, simultaneously.

Label-free electrochemiluminescence biosensor for ultrasensitive detection of telomerase activity in HeLa cells based on extension reaction and intercalation of Ru(phen)3 (2.).

PubMed

Lin, Yue; Yang, Linlin; Yue, Guiyin; Chen, Lifen; Qiu, Bin; Guo, Longhua; Lin, Zhenyu; Chen, Guonan

2016-10-01

Telomerase is one of the most common markers of human malignant tumors, such as uterine, stomach, esophageal, breast, colorectal, laryngeal squamous cell, thyroid, bladder, and so on. It is necessary to develop some sensitive but convenient detection methods for telomerase activity determination. In this study, a label-free and ultrasensitive electrochemiluminescence (ECL) biosensor has been fabricated to detect the activity of telomerase extracted from HeLa cells. Thiolated telomerase substrate (TS) primer was immobilized on the gold electrode surface through gold-sulfur (Au-S) interaction and then elongated by telomerase specifically. Then, it was hybridized with complementary DNA to form double-stranded DNA (dsDNA) fragments on the electrode surface, and Ru(phen)3 (2+) has been intercalated into the dsDNA grooves to act as the ECL probe. The enhanced ECL intensity has a linear relationship with the number of HeLa cells in the range of 5∼5000 and with a detection limit of 2 HeLa cells. The proposed ECL biosensor has high specificity to telomerase in the presence of common interferents. The relative standard deviations (RSDs) were <5 % at 100 HeLa cells. The proposed method provides a convenient approach for telomerase-related cancer screening or diagnosis.

Shock-to-detonation transition of RDX and NTO based composite high explosives: experiments and modeling

NASA Astrophysics Data System (ADS)

Baudin, Gerard; Roudot, Marie; Genetier, Marc

2013-06-01

Composite HMX and NTO based high explosives (HE) are widely used in ammunitions. Designing modern warheads needs robust and reliable models to compute shock ignition and detonation propagation inside HE. Comparing to a pressed HE, a composite HE is not porous and the hot-spots are mainly located at the grain - binder interface leading to a different behavior during shock-to-detonation transition. An investigation of how shock-to-detonation transition occurs inside composite HE containing RDX and NTO is proposed in this lecture. Two composite HE have been studied. The first one is HMX - HTPB 82:18. The second one is HMX - NTO - HTPB 12:72:16. These HE have been submitted to plane sustained shock waves at different pressure levels using a laboratory powder gun. Pressure signals are measured using manganin gauges inserted at several distances inside HE. The corresponding run-distances to detonation are determined using wedge test experiments where the plate impact is performed using a powder gun. Both HE exhibit a single detonation buildup curve in the distance - time diagram of shock-to-detonation transition. This feature seems a common shock-to-detonation behavior for composite HE without porosity. This behavior is also confirmed for a RDX - HTPB 85:15 based composite HE. Such a behavior is exploited to determine the heterogeneous reaction rate versus the shock pressure using a method based on the Cauchy-Riemann problem inversion. The reaction rate laws obtained allow to compute both run-distance to detonation and pressure signals.

The contribution of MIB 1 in the accurate grading of vulvar intraepithelial neoplasia.

PubMed Central

van Beurden, M; de Craen, A J; de Vet, H C; Blaauwgeers, J L; Drillenburg, P; Gallee, M P; de Kraker, N W; Lammes, F B; ten Kate, F J

1999-01-01

AIM: To determine the interobserver variation in scoring presence and grade of vulvar intraepithelial neoplasia (VIN) in haematoxylin/eosin (H/E) slides, MIB 1 slides, and the combined use of H/E and MIB 1 slides. METHODS: 10 slides were stained with H/E and MIB 1 with each of the following diagnoses: normal vulvar skin, VIN 1, VIN 2, and VIN 3. Six observers first scored the H/E slides separately from the MIB 1 slides and second the combined H/E and MIB 1 slides. RESULTS: Unweighted group kappa for MIB 1 was 0.62 and the weighted group kappa was 0.91. This was significantly better than the unweighted group kappa for H/E slides (0.47, p = 0.023) as well as the weighted group kappa for H/E slides (0.82, p = 0.014). There was no improvement by the combined use of H/E and MIB 1 slides. VIN 2 is far less confused with VIN 3 in the combined use of H/E and MIB 1 slides (9%) than in H/E slides (38%) (p = 0.007). There is a tendency to grade VIN in a two tailed grading system rather than a three tailed grading system, which became more apparent with the combined use of H/E and MIB 1 slides. CONCLUSIONS: The interobserver variation with sole use of MIB 1 is better than with the use of H/E stain in VIN. The use of MIB 1 in grading VIN diminishes confusion between VIN 2 and VIN 3 fourfold. A two tailed grading system for VIN seems already to work in daily practice. Images PMID:10690171

The effects of dual-domain mass transfer on the tritium-helium-3 dating method.

PubMed

Neumann, Rebecca B; Labolle, Eric M; Harvey, Charles F

2008-07-01

Diffusion of tritiated water (referred to as tritium) and helium-3 between mobile and immobile regions in aquifers (mass transfer) can affect tritium and helium-3 concentrations and hence tritium-helium-3 (3H/3He) ages that are used to estimate aquifer recharge and groundwater residence times. Tritium and helium-3 chromatographically separate during transport because their molecular diffusion coefficients differ. Simulations of tritium and helium-3 transport and diffusive mass transfer along stream tubes show that mass transfer can shift the 3H/3He age of the tritium and helium-3 concentration ([3H + 3He]) peak to dates much younger than the 1963 peak in atmospheric tritium. Furthermore, diffusive mass-transfer can cause the 3H/3He age to become younger downstream along a stream tube, even as the mean water-age must increase. Simulated patterns of [3H + 3He] versus 3H/3He age using a mass transfer model appear consistent with a variety of field data. These results suggest that diffusive mass transfer should be considered, especially when the [3H + 3He] peak is not well defined or appears younger than the atmospheric peak. 3H/3He data provide information about upstream mass-transfer processes that could be used to constrain mass-transfer models; however, uncritical acceptance of 3H/3He dates from aquifers with immobile regions could be misleading.

The flows of He-3 ions from the region of acceleration downwards to the photosphere

NASA Astrophysics Data System (ADS)

Troitskaia, Evgenia; Arkhangelskaja, Irene; Arkhangelsky, Andrey; Lishnevskii, Andrey

We have studied the powerful solar event of January 20, 2005 by nuclear-physics methods. We based on gamma-emission data of AVS-F apparatus from SONG-D detector onboard CORONAS-F satellite. By the statistical modeling method, proposed in MSU SINP, we calculated the temporal profile of 2.223-MeV line. The calculations were performed under assumptions of Bessel type of accelerated particles energy spectrum, different (3) He content in the region of nuclear reactions to occur, and several density models of the solar atmosphere. The 4.44- and 6.13-MeV gamma-lines temporal profiles were also used. A comparison of the results of modeling with observational 2.223 MeV data reveals the numerical values of all mentioned parameters. The method gives the possibility to detect not only the time-averaged 2.223-MeV gamma-emission parameters over the whole flare, but also their evolution with the time of flare. Particularly, the comparison reveals an increase of the ratio of (3) He/ (1) H concentrations during the flare from 2×10 (-5) at the rise phase of the gamma-ray flux up to 2×10 (-4) at the decay one. The (3) He/ (1) H concentration ratio, averaged over whole time of 2.223-MeV gamma-emission, is equal to (1.40±0.15)×10(-4) . The enlarged ratio of (3) He/ (1) H in the region of nuclear reactions to occur and the increase of this ratio with the time may be understood by the supposition of the gradual accumulation of (3) He in the photosphere and low chromosphere. In this case we can assume that the increased (3) He content in the area of neutron interactions with the medium may be due to the predominant acceleration of (3) He ions in the corona. Then the ions slow down and propagate in the solar atmosphere, downward to the lower chromosphere and photosphere, where they can be accumulated. Several authors proposed different mechanisms of (3) He enrichment. For example, it was suggested that ion-acoustic turbulence could be responsible for this process (L. G. Kocharov et al., 1984), or ion-acoustic turbulence in the crossing electrical and magnetic fields (V.P. Silin et al., 1988), or helical turbulence - in non-potential, convolved magnetic fields (G. Fleyshman , et al., 2012). Thus, we make conclusion about the flows of (3) He ions from the region of acceleration downwards to the low chromosphere and the photosphere. We also have a number of observable confirmations of this supposition and give more detailed substantiations and characteristics of the considered phenomenon. Some obtained numerical results are presented.

[An alchemist or swindler? The case of Zbigniew Dunikowski].

PubMed

Łotysz, Sławomir

2009-01-01

In early 1930s the newspapers and street journals in Europe and the United States were frequently reporting on a case of Zbigniew Dunikowski, a Polish engineer, who claimed to be in possession of a secret formula allowing production of gold from ordinary sand and rocks. He believed that most of those materials contain some particles of gold. For the precious metal however, it takes millions of years to precipitate into the ledges that could be mined. His method was based on a conviction, that the process can be accelerated. Although he was nicknamed "Polish alchemist" very soon, his vain promises attracted attention of financiers and even some European political leaders. After few years of futile experiments, he was sued by his impatient financial backers, and arrested. While in detention, he was allowed to make the last attempt to produce gold and regain his repute and freedom. When this attempt failed, the judge sentenced him for two years in prison and ordered him to repay some 3 million francs ($100,000) to his investors. He was also fined with ... 100 francs fine (some 4 dollars). It can not be definitively stated, whether Dunikowski was truly convicted that his formula for making gold could have been working or he acted as a swindler from the very beginning. He exclaimed that the accusation of fraud was caused by bankers, who would never let his method to undermine the status quo of world's economy. The experiments conducted in Ecole Centrale in Paris during his trial, were assisted buy several eminent French scientist. But although the judge sentenced, that Dunikowki's "secret process for turning sand into gold is an impracticable combination of absurdities and contradictions," Polish engineer was still able to find other backers after being released from French prison. We find the traces of his further activity in Italy, Switzerland, Belgium and Philippines. Finally, in early 1950s he ended his journey in the United States as a political refugee.

Accurate study on the quantum dynamics of the He + HeH(+) (X1Σ+) reaction on a new ab initio potential energy surface for the lowest 1(1)A' electronic singlet state.

PubMed

Xu, Wenwu; Zhang, Peiyu

2013-02-21

A time-dependent quantum wave packet method is used to investigate the dynamics of the He + HeH(+)(X(1)Σ(+)) reaction based on a new potential energy surface [Liang et al., J. Chem. Phys.2012, 136, 094307]. The coupled channel (CC) and centrifugal-sudden (CS) reaction probabilities as well as the total integral cross sections are calculated. A comparison of the results with and without Coriolis coupling revealed that the number of K states N(K) (K is the projection of the total angular momentum J on the body-fixed z axis) significantly influences the reaction threshold. The effective potential energy profiles of each N(K) for the He + HeH(+) reaction in a collinear geometry indicate that the barrier height gradually decreased with increased N(K). The calculated time evolution of CC and CS probability density distribution over the collision energy of 0.27-0.36 eV at total angular momentum J = 50 clearly suggests a lower reaction threshold of CC probabilities. The CC cross sections are larger than the CS results within the entire energy range, demonstrating that the Coriolis coupling effect can effectively promote the He + HeH(+) reaction.

Hyperspherical close-coupling calculations for charge-transfer cross sections in He2++H(1s) collisions at low energies

NASA Astrophysics Data System (ADS)

Liu, Chien-Nan; Le, Anh-Thu; Morishita, Toru; Esry, B. D.; Lin, C. D.

2003-05-01

A theory for ion-atom collisions at low energies based on the hyperspherical close-coupling (HSCC) method is presented. In hyperspherical coordinates the wave function is expanded in analogy to the Born-Oppenheimer approximation where the adiabatic channel functions are calculated with B-spline basis functions while the coupled hyperradial equations are solved by a combination of R-matrix propagation and the slow/smooth variable discretization method. The HSCC method is applied to calculate charge-transfer cross sections for He2++H(1s)→He+(n=2)+H+ reactions at center-of-mass energies from 10 eV to 4 keV. The results are shown to be in general good agreement with calculations based on the molecular orbital (MO) expansion method where electron translation factors (ETF’s) or switching functions have been incorporated in each MO. However, discrepancies were found at very low energies. It is shown that the HSCC method can be used to study low-energy ion-atom collisions without the need to introduce the ad hoc ETF’s, and the results are free from ambiguities associated with the traditional MO expansion approach.

COSMOGRAIL: the COSmological MOnitoring of GRAvItational Lenses. III. Redshift of the lensing galaxy in eight gravitationally lensed quasars

NASA Astrophysics Data System (ADS)

Eigenbrod, A.; Courbin, F.; Meylan, G.; Vuissoz, C.; Magain, P.

2006-06-01

Aims.We measure the redshift of the lensing galaxy in eight gravitationally lensed quasars in view of determining the Hubble parameter H0 from the time delay method. Methods.Deep VLT/FORS1 spectra of lensed quasars are spatially deconvolved in order to separate the spectrum of the lensing galaxies from the glare of the much brighter quasar images. A new observing strategy is devised. It involves observations in Multi-Object-Spectroscopy (MOS) which allows the simultaneous observation of the target and of several PSF and flux calibration stars. The advantage of this method over traditional long-slit observations is a much more reliable extraction and flux calibration of the spectra. Results.For the first time we measure the redshift of the lensing galaxy in three multiply-imaged quasars: SDSS J1138+0314 (z_lens = 0.445), SDSS J1226-0006 (z_lens = 0.517), SDSS J1335+0118 (z_lens = 0.440), and we give a tentative estimate of the redshift of the lensing galaxy in Q 1355-2257 (z_lens = 0.701). We confirm four previously measured redshifts: HE 0047-1756 (z_lens = 0.407), HE 0230-2130 (z_lens = 0.523), HE 0435-1223 (z_lens = 0.454) and WFI J2033-4723 (z_lens = 0.661). In addition, we determine the redshift of the second lensing galaxy in HE 0230-2130 (z_lens = 0.526). The spectra of all lens galaxies are typical for early-type galaxies, except for the second lensing galaxy in HE 0230-2130 which displays prominent [OII] emission.

Testing of heat exchangers in membrane oxygenators using air pressure.

PubMed

Hamilton, Carole; Stein, Jutta; Seidler, Rainer; Kind, Robert; Beck, Karin; Tosok, Jürgen; Upterfofel, Jörg

2006-03-01

All heat exchangers (HE) in membrane oxygenators are tested by the manufacturer for water leaks during the production phase. However, for safety reasons, it is highly recommended that HEs be tested again before clinical use. The most common method is to attach the heater-cooler to the HE and allow the water to recirculate for at least 10 min, during which time a water leak should be evident. To improve the detection of water leaks, a test was devised using a pressure manometer with an integrated bulb used to pressurize the HE with air. The cardiopulmonary bypass system is set up as per protocol. A pressure manometer adapted to a 1/2" tubing is connected to the water inlet side of the oxygenator. The water outlet side is blocked with a short piece of 1/2" deadend tubing. The HE is pressurized with 250 mmHg for at least 30 sec and observed for any drop. Over the last 2 years, only one oxygenator has been detected with a water leak in which the air-method leaktest was performed. This unit was sent back to the manufacturer who confirmed the failure. Even though the incidence of water leaks is very low, it does occur and it is, therefore, important that all HEs are tested before they are used clinically. This method of using a pressure manometer offers many advantages, as the HE can be tested outside of the operating room (OR), allowing earlier testing of the oxygenator, no water contact is necessary, and it is simple, easy and quick to perform.

Automated pulmonary lobar ventilation measurements using volume-matched thoracic CT and MRI

NASA Astrophysics Data System (ADS)

Guo, F.; Svenningsen, S.; Bluemke, E.; Rajchl, M.; Yuan, J.; Fenster, A.; Parraga, G.

2015-03-01

Objectives: To develop and evaluate an automated registration and segmentation pipeline for regional lobar pulmonary structure-function measurements, using volume-matched thoracic CT and MRI in order to guide therapy. Methods: Ten subjects underwent pulmonary function tests and volume-matched 1H and 3He MRI and thoracic CT during a single 2-hr visit. CT was registered to 1H MRI using an affine method that incorporated block-matching and this was followed by a deformable step using free-form deformation. The resultant deformation field was used to deform the associated CT lobe mask that was generated using commercial software. 3He-1H image registration used the same two-step registration method and 3He ventilation was segmented using hierarchical k-means clustering. Whole lung and lobar 3He ventilation and ventilation defect percent (VDP) were generated by mapping ventilation defects to CT-defined whole lung and lobe volumes. Target CT-3He registration accuracy was evaluated using region- , surface distance- and volume-based metrics. Automated whole lung and lobar VDP was compared with semi-automated and manual results using paired t-tests. Results: The proposed pipeline yielded regional spatial agreement of 88.0+/-0.9% and surface distance error of 3.9+/-0.5 mm. Automated and manual whole lung and lobar ventilation and VDP were not significantly different and they were significantly correlated (r = 0.77, p < 0.0001). Conclusion: The proposed automated pipeline can be used to generate regional pulmonary structural-functional maps with high accuracy and robustness, providing an important tool for image-guided pulmonary interventions.

Challenges in application of bioanalytical method on different populations and effect of population on PK.

PubMed

Kale, Prashant; Shukla, Manoj; Soni, Gunjan; Patel, Ronak; Gupta, Shailendra

2014-01-01

Prashant Kale has 22 years of immense experience in the analytical and bioanalytical domain. He is Senior Vice President, Bioequivalence Operations of Lambda Therapeutic Research, India which includes Bioanalytical, Clinics, Clinical data management, Pharmacokinetics and Biostatistics, Protocol writing, Clinical lab and Quality Assurance departments. He has been with Lambda for over 14 years. By qualification he is a M.Sc. and an MBA. Mr. Kale is responsible for the management, technical and administrative functions of the BE unit located at Ahmedabad and Mumbai, India. He is also responsible for leading the process of integration between bioanalytical laboratories and services offered by Lambda at global locations (India and Canada). Mr. Kale has faced several regulatory audits and inspections from leading regulatory bodies including but not limited to DCGI, USFDA, ANVISA, Health Canada, UK MHRA, Turkey MoH, WHO. There are many challenges involved in the application of bioanalytical method on different populations. This includes difference in equipment, material and environment across laboratories, variations in the matrix characteristics in different populations, differences in techniques between analysts such as sample processing and handling and others. Additionally, there is variability in the PK of a drug in different populations. This article shows the effect of different populations on validated bioanalytical method and on the PK of a drug. Hence, the bioanalytical method developed and validated for a specific population may need required modification when applied to another population. Critical consideration of all such aspects is the key to successful implementation of a validated method on different populations.

[The academic characteristics of acupuncture and moxibustion of professor ZHANG Yongshu:a famous acupuncturist in Southern Fujian].

PubMed

Xu, Weiwei; Meng, Xianjun; Zhu, Anning; Wang, Yu; Luo, Wuyougumo; Kuang, Zifang

2017-01-12

Professor ZHANG Yongshu , who studied from professor LIU Zhangjie , is a famous acupuncturist in Quanzhou of Southern Fujian. The publications authored by professor ZHANG Yongshu were collected in this study to summarize his academic characteristics of acupuncture and moxibustion. The result indicated he highly valued the regulation of yang qi , and established the theory of "developing yang to nourish yin ", which proposes to develop yang qi to achieve the effect of culturing yin ; he summarized eight methods to regulate the governor vessel and conception vessel, which can condition the body's yin and yang ; he paid attention to moxibustion therapy and its dosage, and made the best of direct moxibustion. In addition, he focused on meridian theory with effective application of meridian syndrome differentiation; in clinical treatment, he regulated the hand- yangming meridian to treat diseases by nourishing yang , generating yin and regulating fu .

John Tyndall's religion: a fragment

PubMed Central

Cantor, Geoffrey

2015-01-01

Both contemporaries and historians have focused on the high-profile 1874 Belfast Address in which John Tyndall was widely perceived as promulgating atheism. Although some historians have instead interpreted him as a pantheist or an agnostic, it is clear that any such labels do not accurately capture Tyndall's religious position throughout his life. By contrast, this paper seeks to chart Tyndall's religious journey from 1840 (when he was in his late teens) to the autumn of 1848 when he commenced his scientific studies at Marburg. Although he had been imbued with his father's stern conservative Irish Protestantism and opposition to Catholicism, as a youth he seems for a time to have been attracted to Methodism. Later, however, he questioned and rejected his father's religious views and was increasingly drawn to the more spiritual outlook of Ralph Waldo Emerson and Thomas Carlyle, along with a more radical attitude to politics.

Niels Stensen: a 17th century scientist with a modern view of brain organization.

PubMed

Parent, André

2013-07-01

In 1665 the Danish scholar Niels Stensen (1638-1686) reached Paris, where he pronounced a discourse on brain anatomy that was to orient neuroscientists for years to come. In his lecture, Stensen rejected ancient speculations about animal spirits and criticized René Descartes and his followers who, despite a poor knowledge of brain anatomy, elaborated complex models to explain the multifaceted function of what he considered the principal organ of the human mind. He advocated the need for studying the brain through a comparative, developmental and pathological convergent approach and called for appropriate dissection methods and accurate illustrations. His own careful anatomical studies permitted him to precisely depict many brain structures. After pioneering works in paleontology and geology, he devoted himself to theology. In 1677 Stensen converted from Lutheranism to Catholicism and, while working relentlessly as a bishop and apostolic vicar in Northern Europe, he died in self-imposed poverty at age 48.

Onset of η-meson binding in the He isotopes

NASA Astrophysics Data System (ADS)

Barnea, N.; Friedman, E.; Gal, A.

2017-12-01

The onset of binding η (548) mesons in nuclei is studied in the He isotopes by doing precise ηNNN and ηNNNN few-body stochastic variational method calculations for two semi-realistic NN potentials and two energy dependent ηN potentials derived from coupled-channel models of the N* (1535) nucleon resonance. The energy dependence of the ηN subthreshold input is treated self consistently. It is found that a minimal value of the real part of the ηN scattering length aηN close to 1 fm is required to bind η mesons in 3He, yielding then a few MeV η binding in 4He. The onset of η-meson binding in 4He requires that Re aηN exceeds 0.7 fm approximately. These results compare well with results of recent ηNNN and ηNNNN pionless effective field theory calculations. Related optical-model calculations are also discussed.

[From psychotherapy to psychoanalysis: Max Levy-Suhl (1876-1947)].

PubMed

Hermanns, Ludger M; Schröter, Michael; Stroeken, Harry

2014-01-01

From psychotherapy to psychoanalysis: Max Levy-Suhl (1876-1947). Levy-Suhl can be considered one of the great practising psychotherapists in early 20th century Berlin. He was active in various fields, including ophthalmology, forensic adolescent psychiatry and hypnosis. Prominent among his publications were two handbooks of psychotherapeutic methods. His attitude towards psychoanalysis shifted from initial criticism to acceptance. Ca. 1930 he experienced some kind of conversion, resulting in his training at the Berlin Institute and becoming a member of the German Psychoanalytic Society. As a Jew being forced to emigrate in 1933, Levy-Suhl turned to the Netherlands where he had a psychoanalytic children's home in Amersfoort, followed by an analyst's practice in Amsterdam. He survived the German occupation, but apparently as a broken man. After the war he committed suicide.--The paper is complemented by an appendix, containing documents and an extensive bibliography.

Three-cluster dynamics within an ab initio framework

DOE PAGES

Quaglioni, Sofia; Romero-Redondo, Carolina; Navratil, Petr

2013-09-26

In this study, we introduce a fully antisymmetrized treatment of three-cluster dynamics within the ab initio framework of the no-core shell model/resonating-group method. Energy-independent nonlocal interactions among the three nuclear fragments are obtained from realistic nucleon-nucleon interactions and consistent ab initio many-body wave functions of the clusters. The three-cluster Schrödinger equation is solved with bound-state boundary conditions by means of the hyperspherical-harmonic method on a Lagrange mesh. We discuss the formalism in detail and give algebraic expressions for systems of two single nucleons plus a nucleus. Using a soft similarity-renormalization-group evolved chiral nucleon-nucleon potential, we apply the method to amore » 4He+n+n description of 6He and compare the results to experiment and to a six-body diagonalization of the Hamiltonian performed within the harmonic-oscillator expansions of the no-core shell model. Differences between the two calculations provide a measure of core ( 4He) polarization effects.« less

Unified studies of the structure changes and the nuclear reactions in {sup 10}Be

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

Ito, Makoto

2006-08-14

The {alpha}+6He low-energy reactions and the structural changes of 10Be in the microscopic {alpha}+{alpha}+N+N model are studied by the generalized two-center cluster model with the Kohn-Hulthen-Kato variation method. It is found that, in the inelastic scattering to the {alpha}+{sup 6}He(2{sub 1}{sup +}) channel, characteristic enhancements are expected as the results of the parity-dependent non-adiabatic dynamics. The reaction mechanism in breakup of 10Be into the {alpha}+6He continuum is also discussed.

The psychiatrist and the pain clinic.

PubMed

Pilowsky, I

1976-07-01

The author discusses the difficulties inherent in the role of the psychiatrist in a pain clinic as well as some of the recurring problems that he has seen in this setting. He states that the psychiatrist brings to the understanding of pain a multidimensional approach, which is hard for nonpsychiatrist clinicians to accept, and valuable psychophysical methods for evaluating and quantifying pain. He discusses aspects of the interplay between intrapsychic and interpersonal factors in the pain experience, particularly the relationship between pain and guilt, and illustrates these aspects with case reports.

DNA: The Strand that Connects Us All

ScienceCinema

Kaplan, Matt [Univ. of Arizona, Tucson, AZ (United States). Genetics Core Facility

2018-04-26

Learn how the methods and discoveries of human population genetics are applied for personal genealogical reconstruction and anthropological testing. Dr. Kaplan starts with a short general review of human genetics and the biology behind this form of DNA testing. He looks at how DNA testing is performed and how samples are processed in the University of Arizona laboratory. He also examines examples of personal genealogical results from Family Tree DNA and personal anthropological results from the Genographic Project. Finally, he describes the newest project in the UA laboratory, the DNA Shoah Project.

A scientist born in amiens : jacques rohault (1620-1672) (French Title: Un savant amiénois : jacques rohault (1620-1672))

NASA Astrophysics Data System (ADS)

Le Boeuffle, A.

2004-12-01

Jacques Rohault is born in Amiens town at the beginning of the seventeen century. After the Middle Ages, science try to use nex methods and want to abandon Greek's dogmas. Rohault came to Paris to continue his studies and met J.B. Poquelin (Molière). He became a friend an a supporter of René Descartes. He was a very popular scientist. He practised many experiments in public and writed the book La physique to popularize science.

Soft X-ray laser using pumping of 3P and 4P levels of He-like and H-like ions

DOEpatents

Hagelstein, P.L.

1987-04-21

X-ray laser method and apparatus are disclosed for producing coherent radiation at, for example, energies of at least 40 eV, using Be-like Cr, N-like Ni, He-like Na, B-like Cr, Be-like Mn or similar multiply ionized species to pump appropriate high energy transitions in He-like or H-like N, O, F, C or rare gases, with associated laser transition gains of 4-50 cm[sup [minus]1]. 8 figs.

'Quantum interference with slits' revisited

NASA Astrophysics Data System (ADS)

Rothman, Tony; Boughn, Stephen

2011-01-01

Marcella has presented a straightforward technique employing the Dirac formalism to calculate single- and double-slit interference patterns. He claims that no reference is made to classical optics or scattering theory and that his method therefore provides a purely quantum mechanical description of these experiments. He also presents his calculation as if no approximations are employed. We show that he implicitly makes the same approximations found in classical treatments of interference and that no new physics has been introduced. At the same time, some of the quantum mechanical arguments Marcella gives are, at best, misleading.

Finiteness Marking in Boys with Fragile X Syndrome

ERIC Educational Resources Information Center

Sterling, Audra M.; Rice, Mabel L.; Warren, Steven F.

2012-01-01

Purpose: The current study investigated finiteness marking (e.g., he walk "s", he walk "ed") in boys with fragile X syndrome (FXS); the boys were grouped based on receptive vocabulary (i.e., borderline, impaired). Method: Twenty-one boys with the full mutation of fragile X, between the ages of 8 and 16 years participated. The…

Castelli, Benedetto (1578-1643)

NASA Astrophysics Data System (ADS)

Murdin, P.

2000-11-01

Mathematician, born in Brescia, Italy, Benedictine monk, professor at Padua. GALILEO's closest scientific collaborator, he defended, and edited Galileo, he helped his sunspot research, inventing the method of projection so as to view safely the Sun's image with a telescope. His book on hydraulics, Della Misura dell'Acque Correnti, or On the Measurement of Running Waters, founded modern hydrodynam...

Teachers' Conceptions of Student Creativity in Higher Education

ERIC Educational Resources Information Center

Jahnke, Isa; Haertel, Tobias; Wildt, Johannes

2017-01-01

Creativity is one of the important skills of the twenty-first century and central to higher education (HE). When we look closer into research on creativity in HE, however, it is not clear how university teachers conceptualise student creativity. How do teachers grasp, observe and express student creativity? Different methods such as interviews and…

Investigations in Marine Chemistry: Salinity I.

ERIC Educational Resources Information Center

Schlenker, Richard M.

Presented is a unit designed for curriculum infusion and which relies on the hands-on discovery method as an instructive device. The student is introduced to the theory of a functioning salt water conductivity meter. The student explores the resistance of salt water as salinity increases and he treats the data which he has gathered,…

[The dentistry of Blainville and the positivism of Comte].

PubMed

Gysel, C

1989-01-01

COMTE improved BLAINVILLE's acquaintance when he was the secretary of SAINT-SIMON. They became friends. BLAINVILLE aided COMTE in his illness and financial troubles, taught him biology and was one of the first to support his philosophical ideas, through which he became self-conscious of his own value and scientific methods.

Consumerism, Activism, Intrinsic Motivation, and Balance: An Interview with Tim Kasser

ERIC Educational Resources Information Center

Keeley, Jared

2010-01-01

A year after receiving his PhD in psychology from the University of Rochester, Tim Kasser accepted a position at Knox College, in Galesburg, Illinois, where he is currently professor of psychology. He regularly teaches psychology classes on personality, clinical and abnormal psychology, dreaming, and research methods, as well as an…

Physical Activity and Healthy Eating in the After-School Environment

ERIC Educational Resources Information Center

Coleman, Karen J.; Geller, Karly S.; Rosenkranz, Richard R.; Dzewaltowski, David A.

2008-01-01

Background: No research to date has extensively described moderate and vigorous physical activity (MVPA) and healthful eating (HE) opportunities in the after-school environment. The current study described the quality of the after-school environment for its impact on children's MVPA and HE. Methods: An alliance of 7 elementary schools and Boys and…

Open University

ScienceCinema

None

2018-05-25

Michel Pentz was born in South Africa and came to CERN in 1957 as a physicist and president of the Association of Personnel. He is also the founder of the Antiapartheid Movement in Geneva and helped found the Open University in Great Britain. He speaks about pedagogical, cultural and national contexts in which the method can be applied.

Requirements for Programming Languages in Computer-Based Instructional Systems.

ERIC Educational Resources Information Center

Zinn, Karl

The author reviews the instructional programing languages which already exist and describes their methods of presentation, organization, and preparation. He recommends that all research and development projects remain flexible in their choice of programing language for a time yet. He suggests ways to adapt to specific uses and users, to exploit…

Charge transfer in low-energy collisions of H with He+ and H+ with He in excited states

NASA Astrophysics Data System (ADS)

Loreau, J.; Ryabchenko, S.; Muñoz Burgos, J. M.; Vaeck, N.

2018-04-01

The charge transfer process in collisions of excited (n = 2, 3) hydrogen atoms with He+ and in collisions of excited helium atoms with H+ is studied theoretically. A combination of a fully quantum-mechanical method and a semi-classical approach is employed to calculate the charge-exchange cross sections at collision energies from 0.1 eV u‑1 up to 1 keV u‑1. These methods are based on accurate ab initio potential energy curves and non-adiabatic couplings for the molecular ion HeH+. Charge transfer can occur either in singlet or in triplet states, and the differences between the singlet and triplet spin manifolds are discussed. The dependence of the cross section on the quantum numbers n and l of the initial state is demonstrated. The isotope effect on the charge transfer cross sections, arising at low collision energy when H is substituted by D or T, is investigated. Rate coefficients are calculated for all isotopes up to 106 K. Finally, the impact of the present calculations on models of laboratory plasmas is discussed.

A Metastability-Exchange Optical Pumping and Compression System using Polarized 3 He for a Proposed Laboratory Search for Neutron Monopole-Dipole Interactions

NASA Astrophysics Data System (ADS)

Smith, Erick; Ariadne Collaboration

2015-04-01

3 He nuclei polarized using the metastability-exchange optical pumping (MEOP) method have been used for scientific applications such as magnetometry in space, neutron polarization and analysis, and medical imaging. In this talk we explain how this technique is also well-suited for a proposed experiment to search for possible monopole-dipole interactions of polarized 3 He nuclei with matter. The P-odd and T-odd monopole-dipole potential proposed by Moody and Wilczek is proportional to s-> . r-> where s-> is the 3 He spin and r-> is the separation between the particles. It can be induced by axions, and ARIADNE proposes to perform NMR on a polarized 3 He ensemble at 4K with a radially-slotted tungsten disk spinning at a multiple of the 3 He Larmour frequency to induce a resonant monopole-dipole perturbation. The radial slot length variations are chosen to maximize sensitivity to a monopole-dipole interaction range corresponding to the axion window. We describe the advantages that MEOP presents for this experiment and describe the MEOP-based polarized 3 He gas compression system at Indiana University.

A first-principles and experimental study of helium diffusion in periclase MgO

NASA Astrophysics Data System (ADS)

Song, Zhewen; Wu, Henry; Shu, Shipeng; Krawczynski, Mike; Van Orman, James; Cherniak, Daniele J.; Bruce Watson, E.; Mukhopadhyay, Sujoy; Morgan, Dane

2018-02-01

The distribution of He isotopes is used to trace heterogeneities in the Earth's mantle, and is particularly useful for constraining the length scale of heterogeneity due to the generally rapid diffusivity of helium. However, such an analysis is challenging because He diffusivities are largely unknown in lower mantle phases, which can influence the He profiles in regions that cycle through the lower mantle. With this motivation, we have used first-principles simulations based on density functional theory to study He diffusion in MgO, an important lower mantle phase. We first studied the case of interstitial helium diffusion in perfect MgO and found a migration barrier of 0.73 eV at zero pressure. Then we used the kinetic Monte Carlo method to study the case of substitutional He diffusion in MgO, where we assumed that He diffuses on the cation sublattice through cation vacancies. We also performed experiments on He diffusion at atmospheric pressure using ion implantation and nuclear reaction analysis in both as-received and Ga-doped samples. A comparison between the experimental and simulation results are shown. This work provides a foundation for further studies at high-pressure.

[Childbirth without pain. Politics in France during the cold war. ].

PubMed

Caron-Leulliez, Marianne

2006-01-01

Dr. Lamaze introduced Natural Childbirth (ASD) in France in 1951. While this event is significant to the history of obstetrics and women's experience, we would like to concentrate upon another aspect here: how it is situated within the political debates of the period. In the midst of the Cold War, Lamaze was a sympathizer, although not a member of the Communist Party (PCF). He ran a maternity clinic for the CGT, a union affiliated with the PCE During a trip to Russia in 1951, he discovered a new method to relieve pain in labour through a psychological technique inspired by Pavlov. Upon his return, when he dedicated his energies towards the popularization of ASD, he looked for support from the PCF and to draw upon their propaganda network; this subsequently aroused suspicion and hostility. A few years later, ASD received the blessing of women's groups won over by its improvements to birthing. At the moment of Lamaze's triumph, he fell victim to a resurgence of Stalinism. With his team, he denounced the Soviet invasion of Hungary and lost the financial support of the unions which owned the clinic. Exhausted and profoundly disappointed, he died in March 1957.

Evaluation of headspace equilibration methods for quantifying greenhouse gases in groundwater.

PubMed

Jahangir, M M R; Johnston, P; Khalil, M I; Grant, J; Somers, C; Richards, K G

2012-11-30

The objective of the study was to evaluate the different headspace equilibration methods for the quantification of dissolved greenhouse gases in groundwater. Groundwater samples were collected from wells with contrasting hydrogeochemical properties and degassed using the headspace equilibration method. One hundred samples from each well were randomly selected, treatments were applied and headspace gases analysed by gas chromatography. Headspace equilibration treatments varied helium (He):water ratio, shaking time and standing time. Mean groundwater N(2)O, CO(2) and CH(4) concentrations were 0.024 mg N L(-1), 13.71 mg C L(-1) and 1.63 μg C L(-1), respectively. All treatments were found to significantly influence dissolved gas concentrations. Considerable differences in the optimal He:water ratio and standing time were observed between the three gases. For N(2)O, CO(2) and CH(4) the optimum operating points for He:water ratio was 4.4:1, 3:1 and 3.4:1; shaking time was 13, 12 and 13 min; and standing time was 63, 17 and 108 min, respectively. The headspace equilibration method needs to be harmonised to ensure comparability between studies. The experiment reveals that He:water ratio 3:1 and shaking time 13 min give better estimation of dissolved gases than any lower or higher ratios and shaking times. The standing time 63, 17 and 108 min should be applied for N(2)O, CO(2) and CH(4), respectively. Copyright © 2012. Published by Elsevier Ltd.

Spin-isospin excitation of 3He with three-proton final state

NASA Astrophysics Data System (ADS)

Ishikawa, Souichi

2018-01-01

Spin-isospin excitation of the {}^3He nucleus by a proton-induced charge exchange reaction, {}^3He(p,n)ppp, at forward neutron scattering angle is studied in a plane wave impulse approximation (PWIA). In PWIA, cross sections of the reaction are written in terms of proton-neutron scattering amplitudes and response functions of the transition from {}3He to the three-proton state by spin-isospin transition operators. The response functions are calculated with realistic nucleon-nucleon potential models using a Faddeev three-body method. Calculated cross sections agree with available experimental data in substance. Possible effects arising from the uncertainty of proton-neutron amplitudes and three-nucleon interactions in the three-proton system are examined.

Heterodyne lock-in thermography of early demineralized in dental tissues

NASA Astrophysics Data System (ADS)

Wang, Fei; Liu, Jun-yan; Mohummad, Oliullah; Wang, Xiao-chun; Wang, Yang

2017-12-01

Heterodyne lock-in thermography (HeLIT) is a highly sensitive method to detect early demineralized in dental tissues, which is based on nonlinear photothermal phenomena of dental tissues. In this paper, the nonlinear photothermal phenomena of dental tissues was introduced, and then the system of HeLIT was developed. The relationship between laser modulated parameters (modulated frequency and laser intensity) and heterodyne lock-in thermal wave signal was investigated. The comparison between HeLIT and homodyne lock-in thermography (HoLIT) for detecting the different types of dental caries (smooth surface caries, proximal surface caries and occlusal surface caries) were carried out. Experimental results illustrate that the HeLIT has the merits of high sensitivity and high specificity in detecting different types of early caries.

Reply to comments by Riley and Dunlop on He et al. (2015)

USGS Publications Warehouse

Bence, James R.; Madenjian, Charles P.; He, Ji X.; Fielder, David G.; Pothoven, Steven A.; Dobiesz, Norine E.; Johnson, James E.; Ebener, Mark P.; Cottrill, R. Adam; Mohr, Lloyd C.; Koproski, Scott R.

2016-01-01

He et al. (2015) described piscivory patterns in the main basin of Lake Huron 1984-2010, during which there was also a pattern of stepwise declines in the abundance of dominant prey fish species. The approach of He et al. (2015) was to couple age-structured stock assessment and fish bioenergetics models to estimate prey fish consumption, and to compare these patterns with prey fish biomass from a bottom trawl survey. Riley and Dunlop (2015) were highly critical of the methods and conclusions reached by He et al. (2015). They claimed that we incorrectly interpreted the bottom trawl survey data, and did not account for uncertainty. We respond to these and other criticisms below, which we find do not undermine our findings.

The contributions of Lewis Fry Richardson to drainage theory, soil physics, and the soil-plant-atmosphere continuum

NASA Astrophysics Data System (ADS)

Knight, John; Raats, Peter

2016-04-01

The EGU Division on Nonlinear Processes in Geophysics awards the Lewis Fry Richardson Medal. Richardson's significance is highlighted in http://www.egu.eu/awards-medals/portrait-lewis-fry-richardson/, but his contributions to soil physics and to numerical solutions of heat and diffusion equations are not mentioned. We would like to draw attention to those little known contributions. Lewis Fry Richardson (1881-1953) made important contributions to many fields including numerical weather prediction, finite difference solutions of partial differential equations, turbulent flow and diffusion, fractals, quantitative psychology and studies of conflict. He invented numerical weather prediction during World War I, although his methods were not successfully applied until 1950, after the invention of fast digital computers. In 1922 he published the book `Numerical weather prediction', of which few copies were sold and even fewer were read until the 1950s. To model heat and mass transfer in the atmosphere, he did much original work on turbulent flow and defined what is now known as the Richardson number. His technique for improving the convergence of a finite difference calculation is known as Richardson extrapolation, and was used by John Philip in his 1957 semi-analytical solution of the Richards equation for water movement in unsaturated soil. Richardson's first papers in 1908 concerned the numerical solution of the free surface problem of unconfined flow of water in saturated soil, arising in the design of drain spacing in peat. Later, for the lower boundary of his atmospheric model he needed to understand the movement of heat, liquid water and water vapor in what is now called the vadose zone and the soil plant atmosphere system, and to model coupled transfer of heat and flow of water in unsaturated soil. Finding little previous work, he formulated partial differential equations for transient, vertical flow of liquid water and for transfer of heat and water vapor. He paid considerable attention to the balances of water and energy at the soil-atmosphere and plant-atmosphere interfaces, making use of the concept of transfer resistance introduced by Brown and Escombe (1900) for leaf-atmosphere interfaces. He incorporated finite difference versions of all equations into his numerical weather forecasting model. From 1916, Richardson drove an ambulance in France in World War I, did weather computations in his spare time, and wrote a draft of his book. Later researchers such as L.A. Richards, D.A. de Vries and J.R. Philip from the 1930s to the 1950s were unaware that Richardson had anticipated many of their ideas on soil liquid water, heat, water vapor, and the soil-plant-atmosphere system. The Richards (1931) equation could rightly be called the Richardson (1922) equation! Richardson (1910) developed what we now call the Crank Nicolson implicit method for the heat or diffusion equation. To save effort, he used an explicit three level method after the first time step. Crank and Nicolson (1947) pointed out the instability in the explicit method, and used his implicit method for all time steps. Hanks and Bowers (1962) adapted the Crank Nicolson method to solve the Richards equation. So we could say that Hanks and Bowers used the Richardson finite difference method to solve the Richardson equation for soil water flow!

Rotational excitations of N2O in small helium clusters and the role of Bose permutation symmetry

NASA Astrophysics Data System (ADS)

Paesani, F.; Whaley, K. B.

2004-09-01

We present a detailed study of the energetics, structures, and Bose properties of small clusters of 4He containing a single nitrous oxide (N2O) molecule, from N=1 4He up to sizes corresponding to completion of the first solvation shell around N2O (N=16 4He). Ground state properties are calculated using the importance-sampled rigid-body diffusion Monte Carlo method, rotational excited state calculations are made with the projection operator imaginary time spectral evolution method, and Bose permutation exchange and associated superfluid properties are calculated with the finite temperature path integral method. For N⩽5 the helium atoms are seen to form an equatorial ring around the molecular axis, at N=6 helium density starts to occupy the second (local) minimum of the N2O-He interaction at the oxygen side of the molecule, and N=9 is the critical size at which there is onset of helium solvation all along the molecular axis. For N⩾8 six 4He atoms are distributed in a symmetric, quasirigid ring around N2O. Path integral calculations show essentially complete superfluid response to rotation about the molecular axis for N⩾5, and a rise of the perpendicular superfluid response from zero to appreciable values for N⩾8. Rotational excited states are computed for three values of the total angular momentum, J=1-3, and the energy levels fitted to obtain effective spectroscopic constants that show excellent agreement with the experimentally observed N dependence of the effective rotational constant Beff. The non-monotonic behavior of the rotational constant is seen to be due to the onset of long 4He permutation exchanges and associated perpendicular superfluid response of the clusters for N⩾8. We provide a detailed analysis of the role of the helium solvation structure and superfluid properties in determining the effective rotational constants.

Poster - Thur Eve - 16: Four-dimensional x-ray computed tomography and hyperpolarized 3 He magnetic resonance imaging of gas distribution in lung cancer.

PubMed

Mathew, L; Castillo, R; Castillo, E; Yaremko, B; Rodrigues, G; Etemad-Rezai, R; Guerrero, T; Parraga, G

2012-07-01

Dynamic imaging methods such as four-dimensional computed tomography (4DCT) and static imaging methods such as noble gas magnetic resonance imaging (MRI) deliver direct and regional measurements of lung function even in lung cancer patients in whom global lung function measurements are dominated by tumour burden. The purpose of this study was to directly compare quantitative measurements of gas distribution from static hyperpolarized 3 He MRI and dynamic 4DCT in a small group of lung cancer patients. MRI and 4DCT were performed in 11 subjects prior to radiation therapy. MRI was performed at 3.0T in breath-hold after inhalation 1L of hyperpolarized 3 He gas. Gas distribution in 3 He MRI was quantified using a semi-automated segmentation algorithm to generate percent-ventilated volume (PVV), reflecting the volume of gas in the lung normalized to the thoracic cavity volume. 4DCT pulmonary function maps were generated using deformable image registration of six expiratory phase images. The correspondence between identical tissue elements at inspiratory and expiratory phases was used to estimate regional gas distribution and PVV was quantified from these images. After accounting for differences in lung volumes between 3 He MRI (1.9±0.5L ipsilateral, 2.3±0.7 contralateral) and 4DCT (1.2±0.3L ipsilateral, 1.3±0.4L contralateral) during image acquisition, there was no statistically significant difference in PVV between 3 He MRI (72±11% ipsilateral, 79±12% contralateral) and 4DCT (74±3% ipsilateral, 75±4% contralateral). Our results indicate quantitative agreement in the regional distribution of inhaled gas in both static and dynamic imaging methods. PVV may be considered as a regional surrogate measurement of lung function or ventilation. © 2012 American Association of Physicists in Medicine.

Nuclear spin imaging with hyperpolarized nuclei created by brute force method

NASA Astrophysics Data System (ADS)

Tanaka, Masayoshi; Kunimatsu, Takayuki; Fujiwara, Mamoru; Kohri, Hideki; Ohta, Takeshi; Utsuro, Masahiko; Yosoi, Masaru; Ono, Satoshi; Fukuda, Kohji; Takamatsu, Kunihiko; Ueda, Kunihiro; Didelez, Jean-P.; Prossati, Giorgio; de Waard, Arlette

2011-05-01

We have been developing a polarized HD target for particle physics at the SPring-8 under the leadership of the RCNP, Osaka University for the past 5 years. Nuclear polarizaton is created by means of the brute force method which uses a high magnetic field (~17 T) and a low temperature (~ 10 mK). As one of the promising applications of the brute force method to life sciences we started a new project, "NSI" (Nuclear Spin Imaging), where hyperpolarized nuclei are used for the MRI (Magnetic Resonance Imaging). The candidate nuclei with spin ½hslash are 3He, 13C, 15N, 19F, 29Si, and 31P, which are important elements for the composition of the biomolecules. Since the NMR signals from these isotopes are enhanced by orders of magnitudes, the spacial resolution in the imaging would be much more improved compared to the practical MRI used so far. Another advantage of hyperpolarized MRI is that the MRI is basically free from the radiation, while the problems of radiation exposure caused by the X-ray CT or PET (Positron Emission Tomography) cannot be neglected. In fact, the risk of cancer for Japanese due to the radiation exposure through these diagnoses is exceptionally high among the advanced countries. As the first step of the NSI project, we are developing a system to produce hyperpolarized 3He gas for the diagnosis of serious lung diseases, for example, COPD (Chronic Obstructive Pulmonary Disease). The system employs the same 3He/4He dilution refrigerator and superconducting solenoidal coil as those used for the polarized HD target with some modification allowing the 3He Pomeranchuk cooling and the following rapid melting of the polarized solid 3He to avoid the depolarization. In this report, the present and future steps of our project will be outlined with some latest experimental results.

Paul Weiss and the genesis of canonical quantization

NASA Astrophysics Data System (ADS)

Rickles, Dean; Blum, Alexander

2015-12-01

This paper describes the life and work of a figure who, we argue, was of primary importance during the early years of field quantisation and (albeit more indirectly) quantum gravity. A student of Dirac and Born, he was interned in Canada during the second world war as an enemy alien and after his release never seemed to regain a good foothold in physics, identifying thereafter as a mathematician. He developed a general method of quantizing (linear and non-linear) field theories based on the parameters labelling an arbitrary hypersurface. This method (the `parameter formalism' often attributed to Dirac), though later discarded, was employed (and viewed at the time as an extremely important tool) by the leading figures associated with canonical quantum gravity: Dirac, Pirani and Schild, Bergmann, DeWitt, and others. We argue that he deserves wider recognition for this and other innovations.

Combination of plant and insect eggs as food sources facilitates ovarian development in an omnivorous bug Apolygus lucorum (Hemiptera: Miridae).

PubMed

Yuan, Wei; Li, Wenjing; Li, Yunhe; Wu, Kongming G

2013-06-01

Diet nutrient is considered as an important regulatory factor for reproduction of insects. To understand the effect of different food sources on the reproductive physiology of Apolygus lucorum (Meyer-Dür), the ovarian development in adult females was investigated when they were fed on green beans (Gb), combination of green beans Phaseolus vulgaris L and Helicoverpa armigera eggs (GbHe), or H. armigera eggs (He). A female of A. lucorum has two ovaries, and each ovary contained seven yellowish ovarioles. Females fed on Gb or GbHe had larger ovaries and the ovarioles contained larger numbers of oocytes compared with those fed on He. Females in GeHe treatment has significantly higher number of follicles per ovary throughout the whole adult period compared with those in Gb or He treatment. Furthermore, the length of the best developed ovariole was affected by the diet type. The females fed on GbHe had the most developed ovarioles, with significantly longer ovarioles than those fed on Gb or He. A method was described to quantitatively score the degree of ovarian development in the current study. Similarly, the ovarian development scores were significantly higher for females in GbHe treatment than those in other two diet treatments. The ovarian development significantly delayed for females fed on He. Our results demonstrate that A. lucorum, as an omnivorous insect species, can acquire nutrients from both plant and animal origin food sources, and the combination of plants and animal food sources can significantly facilitate the ovary development of its females.

A comparative study of accumulation rates derived by He and Th isotope analysis of marine sediments

NASA Astrophysics Data System (ADS)

Marcantonio, Franco; Kumar, Niraj; Stute, Martin; Anderson, Robert F.; Seidl, Michele A.; Schlosser, Peter; Mix, Alan

1995-07-01

We present a detailed down-core analysis of helium isotope ratios and concentrations for bulk sediments from the central Equatorial Pacific that span the last two glacial-interglacial cycles. Measured 3He/4He ratios range from 1.0 × 10 -5 to 2.1 × 10 -4, or 7.4 to 149 times the atmospheric ratio. The 3He from interplanetary dust particles (IDPs) constitutes virtually all of the 3He measured within the sediment. Because carbonate accumulation rates are high in the Equatorial Pacific, the measured 3He concentrations are lower than have been measured elsewhere, and range from 4.7 × 10 -13 to 3.0 × 10 -12 cm 3STP · g -1. If the cosmic dust 3He-flux is constant with time, sediment mass accumulation rates can be determined from the 3He concentration in sediments. The excess 230Th technique is an entirely independent method for calculating sediment mass accumulation rates because its source is in-situ decay of 234U in seawater. To first order, initial excess 230Th activities correlate with 3He concentrations within this core. Based on the 230Th results, we estimate the 3He-flux to the Earth's surface as (9.6 ± 2.0) × 10 -16 cm 3STP · cm -2 · a -1. If this flux has remained constant over extended periods of time, it can be used to determine sediment accumulation rates beyond the 230Th range (300,000 yr).

Mass retention efficiencies of He accretion onto carbon-oxygen white dwarfs and type Ia supernovae

NASA Astrophysics Data System (ADS)

Wu, C.; Wang, B.; Liu, D.; Han, Z.

2017-07-01

Context. Type Ia supernovae (SNe Ia) play a crucial role in studying cosmology and galactic chemical evolution. They are thought to be thermonuclear explosions of carbon-oxygen white dwarfs (CO WDs) when their masses reach the Chandrasekar mass limit in binaries. Previous studies have suggested that He novae may be progenitor candidates of SNe Ia. However, the mass retention efficiencies during He nova outbursts are still uncertain. Aims: In this article, we aim to study the mass retention efficiencies of He nova outbursts and to investigate whether SNe Ia can be produced through He nova outbursts. Methods: Using the stellar evolution code Modules for Experiments in Stellar Astrophysics, we simulated a series of multicycle He-layer flashes, in which the initial WD masses range from 0.7 to 1.35 M⊙ with various accretion rates. Results: We obtained the mass retention efficiencies of He nova outbursts for various initial WD masses, which can be used in the binary population synthesis studies. In our simulations, He nova outbursts can increase the mass of the WD to the Chandrasekar mass limit and the explosive carbon burning can be triggered in the center of the WD; this suggests that He nova outbursts can produce SNe Ia. Meanwhile, the mass retention efficiencies in the present work are lower than those of previous studies, which leads to a lower birthrates of SNe Ia through the WD + He star channel. Furthermore, we obtained the elemental abundances distribution at the moment of explosive carbon burning, which can be used as the initial input parameters in studying explosion models of SNe Ia.

Collisional depopulation of He(n /sup 1/P) (4< or =n< or =13) in thermal collisions with He(1 /sup 1/S)

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

Pendleton, W.R. Jr.; Larsson, M.; Mannfors, B.

1983-12-01

Total collisional depopulation rates for He(n /sup 1/P) (4< or =n< or =13) in thermal collisions with He(1 /sup 1/S) have been measured using the transient-decay method. Related loss cross sections increase in proportion to n/sup 4/ in the limited range 4< or =n< or =6, reach a maximum of 2600 +- 600 A/sup 2/ at n = 10, and decrease approximately in proportion to n/sup -2.5/ for 11< or =n< or =13. The measurements were found to be inconsistent with a strong ''selection rule,'' ..delta..L = 2, for the He(n /sup 1/P)-He collisions. A model in which ..delta..L formore » the collision is largely unrestricted provides a satisfactory interpretation of the observations, in agreement with recent l-mixing studies of atomic Rydberg levels. The experimental cross sections compare favorably with values calculated using an approximate scaling formula for collisional l mixing and, for n>10, with predictions based on a simple perturbation treatment in the weak-collision approximation.« less

Coupling Detonation Shock Dynamics in a Consistent Manner to Equations of State

NASA Astrophysics Data System (ADS)

Belfield, William

2017-06-01

In hydrocode simulations, detonating high explosives (HE) are often modelled using programmed burn. Each HE cell is assigned a ``burn time'' at which it should begin to behave as HE products in the subsequent simulation. Traditionally, these burn times were calculated using a Huygens construction to propagate the detonation wave at a constant speed corresponding to the planar Chapman-Jouguet (CJ) velocity. The Detonation Shock Dynamics (DSD) model improves upon this approach by treating the local detonation velocity as a function of wave curvature, reflecting that the detonation speed is not constant in reality. However, without alterations being made, this variable detonation velocity is inconsistent with the CJ velocity associated with the HE products equation of state (EOS). Previous work has shown that the inconsistency can be resolved by modifying the HE product EOS, but this treatment is empirical in nature and has only been applied to the JWL EOS. This work investigates different methods to resolve the inconsistency that are applicable both to JWL and to tabular HE product EOS, and their impact on hydrocode simulations.

Fritz Haber: December 9, 1868-January 29, 1934.

PubMed

Witschi, H

2000-08-14

Fritz Haber (1868-1934) was a German physical chemist. Nobel laureate and foreign member of the US National Academy of Sciences. His greatest accomplishment in science was the development of a practical method to prepare nitrogen from air (nitrogen fixation or Haber-Bosch process). While working on the toxicity of war gases. he formulated 'Haber's rule', also known as C x T= constant in order to characterize the toxicity of an inhalant. Between 1919 and 1933. he was one of the leading figures in revitalizing science in Germany. At his institute in Berlin worked such luminaries as Albert Einstein, Lise Meitner and Otto Hahn. His last paper described what became known as the Haber-Weiss reaction. After his death he was for a long time forgotten by the Nazis because he was Jewish and after World War II by the Allies because of his work on war gases in World War I. And yet he was one of the truly great modern scientists. not only because of his science, but also because of the role he played in science politics and policies.

[Two surgery schools: Madrid and Barcelona. Ribera Sans and Salvador Cardenal (150th anniversary of their birth)].

PubMed

Vázquez de Quevedo, Francisco

2003-01-01

Two eminent Spanish surgeons from the positivism period were born 150 years ago: Ribera Sans and Salvador Cardenal. To mark this anniversary I have studied their written work and their contribution to Spanish surgery as pioneers. Each school had its own place although they kept certain parallelism. Ribera worked in Madrid as a professor for 23 years and had many disciples. He initiated digestive, pediatric and thoracic surgery. He was a professor at San Carlos just like the surgeons: San Martín and Guedea. He was director of the Niño Jesús Hospital and a R. A. N. M. academic. Cardenal is a distinguished surgeon who carried out his work in Barcelona. He extended the use of the antiseptic method in Spanish surgery. He became Director of the Sagrado Corazón Hospital. He was also named Honorary professor of surgery and a member of the Royal School of Surgery in England, and R. A. Barcelona. His work was closely related to Dr. Ferrán's. His son was León Cardenal.

Surface modification and deuterium retention in reduced-activation steels exposed to low-energy, high-flux pure and helium-seeded deuterium plasmas

NASA Astrophysics Data System (ADS)

Alimov, V. Kh; Ogorodnikova, O. V.; Hatano, Y.; Gasparyan, YuM.; Efimov, V. S.; Mayer, M.; Zhou, Z.; Oyaizu, M.; Isobe, K.; Nakamura, H.; Hayashi, T.

2018-04-01

Surface topography of and deuterium (D) retention in reduced activation ferritic-martensitic Eurofer'97 and ferritic oxide dispersion strengthening ODS-16Cr steels have been studied after exposure at 600 K to low-energy (70 and 200 eV), high-flux (∼1022 D/m2s) pure D and D-10%He plasmas with D fluence of 2 × 1025 D/m2. The methods used were scanning electron microscopy, energy-scanning D(3He,p)4He nuclear reaction, and thermal desorption spectroscopy. As a result of the plasma exposures, nano-sized structures are formed on the steel surfaces. After exposure to pure D plasmas, a significant fraction of D is accumulated in the bulk, at depths larger than 8 μm. After exposures to D-He plasmas, D is retained mainly in the near-surface layers. In spite of the fact that the He fluence was lower than the D fluence, the He retention in the steels is one order of magnitude higher than the D retention.

Experimental investigation and numerical simulation of 3He gas diffusion in simple geometries: implications for analytical models of 3He MR lung morphometry.

PubMed

Parra-Robles, J; Ajraoui, S; Deppe, M H; Parnell, S R; Wild, J M

2010-06-01

Models of lung acinar geometry have been proposed to analytically describe the diffusion of (3)He in the lung (as measured with pulsed gradient spin echo (PGSE) methods) as a possible means of characterizing lung microstructure from measurement of the (3)He ADC. In this work, major limitations in these analytical models are highlighted in simple diffusion weighted experiments with (3)He in cylindrical models of known geometry. The findings are substantiated with numerical simulations based on the same geometry using finite difference representation of the Bloch-Torrey equation. The validity of the existing "cylinder model" is discussed in terms of the physical diffusion regimes experienced and the basic reliance of the cylinder model and other ADC-based approaches on a Gaussian diffusion behaviour is highlighted. The results presented here demonstrate that physical assumptions of the cylinder model are not valid for large diffusion gradient strengths (above approximately 15 mT/m), which are commonly used for (3)He ADC measurements in human lungs. (c) 2010 Elsevier Inc. All rights reserved.

Detection of main tidal frequencies using least squares harmonic estimation method

NASA Astrophysics Data System (ADS)

Mousavian, R.; Hossainali, M. Mashhadi

2012-11-01

In this paper the efficiency of the method of Least Squares Harmonic Estimation (LS-HE) for detecting the main tidal frequencies is investigated. Using this method, the tidal spectrum of the sea level data is evaluated at two tidal stations: Bandar Abbas in south of Iran and Workington on the eastern coast of the UK. The amplitudes of the tidal constituents at these two tidal stations are not the same. Moreover, in contrary to the Workington station, the Bandar Abbas tidal record is not an equispaced time series. Therefore, the analysis of the hourly tidal observations in Bandar Abbas and Workington can provide a reasonable insight into the efficiency of this method for analyzing the frequency content of tidal time series. Furthermore, applying the method of Fourier transform to the Workington tidal record provides an independent source of information for evaluating the tidal spectrum proposed by the LS-HE method. According to the obtained results, the spectrums of these two tidal records contain the components with the maximum amplitudes among the expected ones in this time span and some new frequencies in the list of known constituents. In addition, in terms of frequencies with maximum amplitude; the power spectrums derived from two aforementioned methods are the same. These results demonstrate the ability of LS-HE for identifying the frequencies with maximum amplitude in both tidal records.

Archimedes Quadrature of the Parabola: A Mechanical View

ERIC Educational Resources Information Center

Oster, Thomas J.

2006-01-01

In his famous quadrature of the parabola, Archimedes found the area of the region bounded by a parabola and a chord. His method was to fill the region with infinitely many triangles each of whose area he could calculate. In his solution, he stated, without proof, three preliminary propositions about parabolas that were known in his time, but are…

Asymmetry in the Perception of Friendship in Students Groups

ERIC Educational Resources Information Center

Lancieri, Luigi

2017-01-01

Several studies point out the link between sociability and academic results. In this paper, we highlight a phenomenon of asymmetry in the perception of friendship. This occurs when a student think he has more or less friends than he really has. We present an experimental method that allows us to analyze this question in relation with the academic…

A Sense of Tradition: R. J .W. Selleck and the Purpose of Educational History

ERIC Educational Resources Information Center

Macintyre, Stuart

2014-01-01

This short account of R.J.W. (Dick) Selleck's career and research suggests how he reoriented study of the history of education in Australia. Using a historicist method, he examined educational theories and practices to elucidate the educational purposes they were intended to serve. Through major biographies of leading educationists and…

STUDY TO DETERMINE THE FEASIBILITY OF USING A GROUND-PENETRATING RADAR FOR MORE EFFECTIVE REMEDIATION OF SUBSURFACE CONTAMINATION

EPA Science Inventory

Remediation of hazardous material spills is often costly and entails cumbersome procedures. he traditional method is to drill core samples in the area where the contaminant is thought to be present and then analyze these samples in a laboratory. he denser the sampling grid, the m...

Adams, Walter Sydney (1876-1956)

NASA Astrophysics Data System (ADS)

Murdin, P.

2000-11-01

Born in Antioch, Syria, to American missionary parents, he worked under GEORGE HALE at Yerkes Observatory at the University of Chicago, accompanying Hale to California to set up the Mount Wilson Observatory, and becoming its director on Hale's retirement. He helped design the 200 in telescope for Mount Palomar Observatory. His method of spectroscopic parallaxes, a technique using spectra to give ...

The Architect of Progressive Education: John Dewey or Booker T. Washington.

ERIC Educational Resources Information Center

Generals, Donald, Jr.

This paper traces the professional life of the educator Booker T. Washington. It shows that although he was active at Tuskegee Institute during the years of the development of the progressive education movement, he is virtually ignored in progressive education's body of literature. The paper describes the "project method" which was a way…

Eckert, Wallace John (1902-71)

NASA Astrophysics Data System (ADS)

Murdin, P.

2000-11-01

Computer scientist and astronomer. Born in Pittsburgh, PA, Eckert was a pioneer of the use of IBM punched card equipment for astronomical calculations. As director of the US Nautical Almanac Office he introduced computer methods to calculate and print tables instead of relying on human `computers'. When, later, he became director of the Watson Scientific Computing Laboratory at Columbia Universit...

Room 109's Portfolios and Our High School Writing Center

ERIC Educational Resources Information Center

Kent, Richard

2006-01-01

In this article, the author describes how he had revised his course expectations and English teaching methods in Room 109 at Mountain Valley High School in Rumford, Maine, with support from the writing center staff. He instituted thematic portfolios, self-selected reading with a wide range of projects in response to that reading, periodic student…

He's Frequency Formulation for Nonlinear Oscillators

ERIC Educational Resources Information Center

Geng, Lei; Cai, Xu-Chu

2007-01-01

Based on an ancient Chinese algorithm, J H He suggested a simple but effective method to find the frequency of a nonlinear oscillator. In this paper, a modified version is suggested to improve the accuracy of the frequency; two examples are given, revealing that the obtained solutions are of remarkable accuracy and are valid for the whole solution…

Forest regeneration research at Fort Valley

Treesearch

L. J. (Pat) Heidmann

2008-01-01

When G. A. Pearson arrived at Fort Valley to establish the first Forest Service Experiment Station he found many open park-like stands similar to those in Figure 1. Within two years, Pearson had outlined the major factors detrimental to the establishment of ponderosa pine seedlings (Pearson 1910). During the next almost 40 years, he wrote many articles on methods of...

Forest regeneration research (P-53)

Treesearch

Leroy J. (Pat) Heidmann

2008-01-01

When G. A. Pearson arrived at Fort Valley to establish the first Forest Service Experiment Station he found many open park-like stands similar to those in Figure 1. Within two years, Pearson had outlined the major factors detrimental to the establishment of ponderosa pine seedlings (Pearson 1910). During the next almost 40 years, he wrote many articles on methods of...

Slow Transformation: Teacher Research and Shifting Teacher Practices

ERIC Educational Resources Information Center

Patterson, Thomas H.; Crumpler, Thomas P.

2009-01-01

As a teacher with more than 30 years experience at the middle school, secondary, and college level, primarily in English studies, Patterson (the first author) decided a few years ago to reexamine his practices and instructional methods. He wondered what would be the effects on him and his students when he would begin to utilize ideas emanating…

The Evaluation of the Performed Activities According to ELVES Method

ERIC Educational Resources Information Center

Erdem, Aliye

2018-01-01

Listening habit has an important share in the individual perceiving his/her environment and the world properly and complying with the social environment he/she lives. Because listening is an important skill which enables the individual to use the communication skills he/she learned both at school and out of school properly and to understand…

Count Nicolaus Ludwig Von Zinzendorf’s Theory for Missions Portrayed at Herrnhut and by Selected 18th-20th Century Moravian Missions.

DTIC Science & Technology

1986-01-01

the progressive methods in advanced missions with churches, schools, gardens, vineyards and orchards, sheep herding, gristmill, cutlery, printing press...pear tree soon became gardens, orchards and vineyards . His success led to Dutch Church and Boer farmer insistence that he leave. Hoping to return, he

Advanced and Higher Vocational Education in Scotland: Recontextualising the Provision of HE in FE

ERIC Educational Resources Information Center

Husband, Gary; Jeffrey, Michael

2016-01-01

This article explores the nature of provision of higher education (HE) within the further education (FE) context and discusses the prevalent cultures of delivery. Attention is drawn to the skills and pedagogic methods prevalent within FE that could offer significant benefits to the delivery of advanced-level apprenticeships and applied…

Double ionization in R -matrix theory using a two-electron outer region

NASA Astrophysics Data System (ADS)

Wragg, Jack; Parker, J. S.; van der Hart, H. W.

2015-08-01

We have developed a two-electron outer region for use within R -matrix theory to describe double ionization processes. The capability of this method is demonstrated for single-photon double ionization of He in the photon energy region between 80 and 180 eV. The cross sections are in agreement with established data. The extended R -matrix with time dependence method also provides information on higher-order processes, as demonstrated by the identification of signatures for sequential double ionization processes involving an intermediate He+ state with n =2 .

Ventilation distribution in rats: Part 2 – A comparison of electrical impedance tomography and hyperpolarised helium magnetic resonance imaging

PubMed Central

2012-01-01

Background Hyperpolarised helium MRI (He3 MRI) is a new technique that enables imaging of the air distribution within the lungs. This allows accurate determination of the ventilation distribution in vivo. The technique has the disadvantages of requiring an expensive helium isotope, complex apparatus and moving the patient to a compatible MRI scanner. Electrical impedance tomography (EIT) a non-invasive bedside technique that allows constant monitoring of lung impedance, which is dependent on changes in air space capacity in the lung. We have used He3MRI measurements of ventilation distribution as the gold standard for assessment of EIT. Methods Seven rats were ventilated in supine, prone, left and right lateral position with 70% helium/30% oxygen for EIT measurements and pure helium for He3 MRI. The same ventilator and settings were used for both measurements. Image dimensions, geometric centre and global in homogeneity index were calculated. Results EIT images were smaller and of lower resolution and contained less anatomical detail than those from He3 MRI. However, both methods could measure positional induced changes in lung ventilation, as assessed by the geometric centre. The global in homogeneity index were comparable between the techniques. Conclusion EIT is a suitable technique for monitoring ventilation distribution and inhomgeneity as assessed by comparison with He3 MRI. PMID:22966835

Multiscale rescaled range analysis of EEG recordings in sevoflurane anesthesia.

PubMed

Liang, Zhenhu; Li, Duan; Ouyang, Gaoxiang; Wang, Yinghua; Voss, Logan J; Sleigh, Jamie W; Li, Xiaoli

2012-04-01

The Hurst exponent (HE) is a nonlinear method measuring the smoothness of a fractal time series. In this study we applied the HE index, extracted from electroencephalographic (EEG) recordings, as a measure of anesthetic drug effects on brain activity. In 19 adult patients undergoing sevoflurane general anesthesia, we calculated the HE of the raw EEG; comparing the maximal overlap discrete wavelet transform (MODWT) with the traditional rescaled range (R/S) analysis techniques, and with a commercial index of depth of anesthesia - the response entropy (RE). We analyzed each wavelet-decomposed sub-band as well as the combined low frequency bands (HEOLFBs). The methods were compared in regard to pharmacokinetic/pharmacodynamic (PK/PD) modeling, and prediction probability. All the low frequency band HE indices decreased when anesthesia deepened. However the HEOLFB was the best index because: it was less sensitive to artifacts, most closely tracked the exact point of loss of consciousness, showed a better prediction probability in separating the awake and unconscious states, and tracked sevoflurane concentration better - as estimated by the PK/PD models. The HE is a useful measure for estimating the depth of anesthesia. It was noted that HEOLFB showed the best performance for tracking drug effect. The HEOLFB could be used as an index for accurately estimating the effect of anesthesia on brain activity. Copyright © 2011 International Federation of Clinical Neurophysiology. All rights reserved.

Laser-Ablation (U-Th)/He Geochronology

NASA Astrophysics Data System (ADS)

Hodges, K.; Boyce, J.

2003-12-01

Over the past decade, ultraviolet laser microprobes have revolutionized the field of 40Ar/39Ar geochronology. They provide unprecedented information about Ar isotopic zoning in natural crystals, permit high-resolution characterization of Ar diffusion profiles produced during laboratory experiments, and enable targeted dating of multiple generations of minerals in thin section. We have modified the analytical protocols used for 40Ar/39Ar laser microanalysis for use in (U-Th)/He geochronologic studies. Part of the success of the 40Ar/39Ar laser microprobe stems from fact that measurements of Ar isotopic ratios alone are sufficient for the calculation of a date. In contrast, the (U-Th)/He method requires separate analysis of U+Th and 4He. Our method employs two separate laser microprobes for this process. A target mineral grain is placed in an ultrahigh vacuum chamber fitted with a window of appropriate composition to transmit ultraviolet radiation. A focused ArF (193 nm) excimer laser is used to ablate tapered cylindrical pits on the surface of the target. The liberated material is scrubbed with a series of getters in a fashion similar to that used for 40Ar/39Ar geochronology, and the 4He abundance is determined using a quadrupole mass spectrometer with well-calibrated sensitivity. A key requirement for calculation of the 4He abundance in the target is a precise knowledge of the volume of the ablation pit. This is the principal reason why we employ the ArF excimer for 4He analysis rather than a less-expensive frequency-multiplied Nd-YAG laser; the excimer creates tapered cylindrical pits with extremely reproducible and easily characterized geometry. After 4He analysis, U and Th are measured on the same sample surface using the more familiar technique of laser-ablation inductively coupled plasma mass spectrometry (LA-ICPMS). Our early experiments have been done using a frequency-quintupled Nd-YAG microprobe (213nm), While the need to analyze U+Th and He in separate ablation experiments results in considerably worse spatial resolution than that typically possible for 40Ar/39Ar laser microprobe dating, it is possible to site the LA-ICPMS ablation pit within a few microns of the pit used for He extraction, or to simply re-occupy and enlarge the original ablation pit. The potential effective spatial resolution of the technique is thus on the order of a few tens to roughly 100 microns. As a proof-of-concept exercise, we have applied this technique to fluorapatite from Cerro de Mercado, Durango, Mexico, which has a generally accepted (U-Th)/He age of 32.1 +/- 3.4 Ma (2 sigma) based on single-crystal fusion analyses reported by House et al. (2000, EPSL). Using the approach described above, we made 48 separate age measurements on a 12 mm polished section cut through a single crystal of Durango fluorapatite perpendicular to its c axis. The measured dates yield a mean of 34.9 +/- 5.1 Ma (2 sigma), with a total dispersion of dates comparable to that reported by House et al. Much of the apparent age variation observed in both studies is due to documented U+Th heterogeneities in single crystals of the Durango fluorapatite. Nevertheless, the consistency of the laser ablation and conventional results for this material is striking. Compared to conventional laser and furnace methods of (U-Th)/He geochronology, the laser microprobe approach offers substantially improved spatial resolution, and the ability to avoid (or at least minimize) alpha-ejection corrections. In addition, the method affords improved sample throughput, such that age estimates for homogeneous materials can be made with considerably higher precision based on a larger number of analyses.

Dr. Hugh L. Dryden - portrait

NASA Technical Reports Server (NTRS)

1959-01-01

Dr. Hugh Latimer Dryden, had many titles after his name in his lifetime. In 1949 he became the director of the National Advisory Committee for Aeronautics (NACA). Dr. Dryden received many accolades and awards both during his life and after his death, but the greatest and most appropriate honor came on March 26, 1976, when NASA renamed the NASA Flight Research Center as the NASA Hugh L. Dryden Flight Research Center. At the dedication ceremony NASA Administrator James C. Fletcher stated: 'in 1924, when the fastest racing planes did well to fly at 280 m.p.h., Dryden was already probing the transonic range of . . . flight. Later in the 1920s, he sought to develop methods of accurately measuring . . . turbulence in wind tunnels. In 1938 he was the first American to deliver the Wright Brothers lecture. His 'Turbulence and the Boundary Layer' became a classic summary on the subject. It is most fitting that this Flight Research Center, with its unique and highly specialized capability for solving aerospace problems, should memorialize the genius of Hugh Dryden.' Dr. Dryden was initially an aerodynamicist with the National Bureau of Standards. He did important early work in high-speed aerodynamics. In 1947 he became the director of aeronautical research for the NACA (a predecessor of the National Aeronautics and Space Administration). Two years later, he became NACA's director, a position he held until 1958 when he became deputy administrator of NASA.

Model-independent determination of the astrophysical S factor in laser-induced fusion plasmas

NASA Astrophysics Data System (ADS)

Lattuada, D.; Barbarino, M.; Bonasera, A.; Bang, W.; Quevedo, H. J.; Warren, M.; Consoli, F.; De Angelis, R.; Andreoli, P.; Kimura, S.; Dyer, G.; Bernstein, A. C.; Hagel, K.; Barbui, M.; Schmidt, K.; Gaul, E.; Donovan, M. E.; Natowitz, J. B.; Ditmire, T.

2016-04-01

In this work, we present a new and general method for measuring the astrophysical S factor of nuclear reactions in laser-induced plasmas and we apply it to :mmultiscripts>(d ,n )3He . The experiment was performed with the Texas Petawatt Laser, which delivered 150-270 fs pulses of energy ranging from 90 to 180 J to D2 or CD4 molecular clusters (where D denotes 2H ) . After removing the background noise, we used the measured time-of-flight data of energetic deuterium ions to obtain their energy distribution. We derive the S factor using the measured energy distribution of the ions, the measured volume of the fusion plasma, and the measured fusion yields. This method is model independent in the sense that no assumption on the state of the system is required, but it requires an accurate measurement of the ion energy distribution, especially at high energies, and of the relevant fusion yields. In the :mmultiscripts>(d ,n )3He and 3He(d ,p )4He cases discussed here, it is very important to apply the background subtraction for the energetic ions and to measure the fusion yields with high precision. While the available data on both ion distribution and fusion yields allow us to determine with good precision the S factor in the d +d case (lower Gamow energies), for the d +3He case the data are not precise enough to obtain the S factor using this method. Our results agree with other experiments within the experimental error, even though smaller values of the S factor were obtained. This might be due to the plasma environment differing from the beam target conditions in a conventional accelerator experiment.

Model-independent determination of the astrophysical S factor in laser-induced fusion plasmas

DOE PAGES

Lattuada, D.; Barbarino, M.; Bonasera, A.; ...

2016-04-19

In this paper, we present a new and general method for measuring the astrophysical S factor of nuclear reactions in laser-induced plasmas and we apply it to 2H(d,n) 3He. The experiment was performed with the Texas Petawatt Laser, which delivered 150–270 fs pulses of energy ranging from 90 to 180 J to D 2 or CD 4 molecular clusters (where D denotes 2H). After removing the background noise, we used the measured time-of-flight data of energetic deuterium ions to obtain their energy distribution. We derive the S factor using the measured energy distribution of the ions, the measured volume ofmore » the fusion plasma, and the measured fusion yields. This method is model independent in the sense that no assumption on the state of the system is required, but it requires an accurate measurement of the ion energy distribution, especially at high energies, and of the relevant fusion yields. In the 2H(d,n) 3He and 3He(d,p) 4He cases discussed here, it is very important to apply the background subtraction for the energetic ions and to measure the fusion yields with high precision. While the available data on both ion distribution and fusion yields allow us to determine with good precision the S factor in the d+d case (lower Gamow energies), for the d+ 3He case the data are not precise enough to obtain the S factor using this method. Our results agree with other experiments within the experimental error, even though smaller values of the S factor were obtained. This might be due to the plasma environment differing from the beam target conditions in a conventional accelerator experiment.« less

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

Lattuada, D.; Barbarino, M.; Bonasera, A.

In this paper, we present a new and general method for measuring the astrophysical S factor of nuclear reactions in laser-induced plasmas and we apply it to 2H(d,n) 3He. The experiment was performed with the Texas Petawatt Laser, which delivered 150–270 fs pulses of energy ranging from 90 to 180 J to D 2 or CD 4 molecular clusters (where D denotes 2H). After removing the background noise, we used the measured time-of-flight data of energetic deuterium ions to obtain their energy distribution. We derive the S factor using the measured energy distribution of the ions, the measured volume ofmore » the fusion plasma, and the measured fusion yields. This method is model independent in the sense that no assumption on the state of the system is required, but it requires an accurate measurement of the ion energy distribution, especially at high energies, and of the relevant fusion yields. In the 2H(d,n) 3He and 3He(d,p) 4He cases discussed here, it is very important to apply the background subtraction for the energetic ions and to measure the fusion yields with high precision. While the available data on both ion distribution and fusion yields allow us to determine with good precision the S factor in the d+d case (lower Gamow energies), for the d+ 3He case the data are not precise enough to obtain the S factor using this method. Our results agree with other experiments within the experimental error, even though smaller values of the S factor were obtained. This might be due to the plasma environment differing from the beam target conditions in a conventional accelerator experiment.« less

Towards Longitudinal Mapping of Extracellular pH in Gliomas

PubMed Central

Huang, Yuegao; Coman, Daniel; Herman, Peter; Rao, Jyotsna U.; Maritim, Samuel; Hyder, Fahmeed

2016-01-01

Biosensor Imaging of Redundant Deviation in Shifts (BIRDS), an ultrafast chemical shift imaging technique, requires infusion of paramagnetic probes like 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetrakis(methylene phosphonate (DOTP8−) complexed with thulium (Tm3+) ion (i.e., TmDOTP5−), where the pH-sensitive resonances of hyperfine-shifted nonexchangeable protons contained within the paramagnetic magnetic resonance probe are detected. While imaging extracellular pH (pHe) with BIRDS meets an important cancer research need by mapping the intratumoral-peritumoral pHe gradient, the surgical intervention used to raise the probe’s plasma concentration limits longitudinal scans on the same subject. Here we describe using probenecid (i.e., an organic anion transporter inhibitor) to temporarily restrict renal clearance of TmDOTP5−, thereby facilitating molecular imaging by BIRDS without surgical intervention. Co-infusion of probenecid with TmDOTP5− increased the probe’s distribution into various organs, including the brain, compared with when infusing TmDOTP5− alone. In vivo BIRDS data using probenecid/TmDOTP5− co-infusion method in rats bearing RG2, 9L, and U87 brain tumors showed intratumoral-peritumoral pHe gradients that were unaffected by the probe dose. This co-infusion method can be used for pHe mapping with BIRDS in preclinical models for tumor characterization and therapeutic monitoring given the possibility of repeated scans with BIRDS (e.g., over days and even weeks) in the same subject. The longitudinal pHe readout by probenecid/TmDOTP5− co-infusion method for BIRDS adds translational value in tumor assessment and treatment. PMID:27472471

Application of P-wave Hybrid Theory to the Scattering of Electrons from He+ and Resonances in He and H ion

NASA Technical Reports Server (NTRS)

Bhatia, A. K.

2012-01-01

The P-wave hybrid theory of electron-hydrogen elastic scattering [Phys. Rev. A 85, 052708 (2012)] is applied to the P-wave scattering from He ion. In this method, both short-range and long-range correlations are included in the Schroedinger equation at the same time, by using a combination of a modified method of polarized orbitals and the optical potential formalism. The short-correlation functions are of Hylleraas type. It is found that the phase shifts are not significantly affected by the modification of the target function by a method similar to the method of polarized orbitals and they are close to the phase shifts calculated earlier by Bhatia [Phys. Rev. A 69, 032714 (2004)]. This indicates that the correlation function is general enough to include the target distortion (polarization) in the presence of the incident electron. The important fact is that in the present calculation, to obtain similar results only a 20-term correlation function is needed in the wave function compared to the 220- term wave function required in the above-mentioned calculation. Results for the phase shifts, obtained in the present hybrid formalism, are rigorous lower bounds to the exact phase shifts. The lowest P-wave resonances in He atom and hydrogen ion have been calculated and compared with the results obtained using the Feshbach projection operator formalism [Phys. Rev. A, 11, 2018 (1975)]. It is concluded that accurate resonance parameters can be obtained by the present method, which has the advantage of including corrections due to neighboring resonances, bound states and the continuum in which these resonance are embedded.

Neutron-Impact Ionization of H and He

NASA Astrophysics Data System (ADS)

Lee, T.-G.; Ciappina, M. F.; Robicheaux, F.; Pindzola, M. S.

2014-05-01

Perturbative distorted-wave and non-perturbative close-coupling methods are used to study neutron-impact ionization of H and He. For single ionization of H, we find excellent agreement between the distorted-wave and close-coupling results at all incident energies. For double ionization of He, we find poor agreement between the distorted-wave and close-coupling results, except at the highest incident energies. We present the ratio of double to single ionization for He as a guide to experimental checks of theory at low energies and experimental confirmation of the rapid rise of the ratio at high energies. This work was supported in part by grants from NSF and US DoE. Computational work was carried out at NERSC in Oakland, California, NICS in Knoxville, Tennessee, and OLCF in Oak Ridge, Tennessee.

How Many-Body Correlations and α Clustering Shape He 6

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

Romero-Redondo, Carolina; Quaglioni, Sofia; Navrátil, Petr

The Borromean 6He nucleus is an exotic system characterized by two halo neutrons orbiting around a compact 4He (or α) core, in which the binary subsystems are unbound. The simultaneous reproduction of its small binding energy and extended matter and point-proton radii has been a challenge for ab initio theoretical calculations based on traditional bound-state methods. Using soft nucleon-nucleon interactions based on chiral effective field theory potentials, we show that supplementing the model space with 4He + n + n cluster degrees of freedom largely solves this issue. Lastly, we analyze the role played by α clustering and many-body correlations,more » and study the dependence of the energy spectrum on the resolution scale of the interaction.« less

A helium-3/helium-4 dilution cryocooler for operation in zero gravity

NASA Technical Reports Server (NTRS)

Hendricks, John B.

1988-01-01

This research effort covered the development of He-3/He-4 dilution cryocooler cycles for use in zero gravity. The dilution cryocooler is currently the method of choice for producing temperatures below 0.3 Kelvin in the laboratory. However, the current dilution cryocooler depends on gravity for their operation, so some modification is required for zero gravity operation. In this effort, we have demonstrated, by analysis, that the zero gravity dilution cryocooler is feasible. We have developed a cycle that uses He-3 circulation, and an alternate cycle that uses superfluid He-4 circulation. The key elements of both cycles were demonstrated experimentally. The development of a true 'zero-gravity' dilution cryocooler is now possible, and should be undertaken in a follow-on effort.

How Many-Body Correlations and α Clustering Shape He 6

DOE PAGES

Romero-Redondo, Carolina; Quaglioni, Sofia; Navrátil, Petr; ...

2016-11-23

The Borromean 6He nucleus is an exotic system characterized by two halo neutrons orbiting around a compact 4He (or α) core, in which the binary subsystems are unbound. The simultaneous reproduction of its small binding energy and extended matter and point-proton radii has been a challenge for ab initio theoretical calculations based on traditional bound-state methods. Using soft nucleon-nucleon interactions based on chiral effective field theory potentials, we show that supplementing the model space with 4He + n + n cluster degrees of freedom largely solves this issue. Lastly, we analyze the role played by α clustering and many-body correlations,more » and study the dependence of the energy spectrum on the resolution scale of the interaction.« less

Coherent soft X-ray high-order harmonics using tight-focusing laser pulses in the gas mixture.

PubMed

Lu, Faming; Xia, Yuanqin; Zhang, Sheng; Chen, Deying; Zhao, Yang; Liu, Bin

2014-01-01

We experimentally study the harmonics from a Xe-He gas mixture using tight-focusing femtosecond laser pulses. The spectrum in the mixed gases exhibits an extended cutoff region from the harmonic H21 to H27. The potential explanation is that the harmonics photons from Xe contribute the electrons of He atoms to transmit into the excited-state. Therefore, the harmonics are emitted from He atoms easily. Furthermore, we show that there are the suppressed harmonics H15 and H17 in the mixed gases. The underlying mechanism is the destructive interference between harmonics generated from different atoms. Our results indicate that HHG from Xe-He gas mixture is an efficient method of obtaining the coherent soft X-ray source.

Steponas Kolupaila's contribution to hydrological science development

NASA Astrophysics Data System (ADS)

Valiuškevičius, Gintaras

2017-08-01

Steponas Kolupaila (1892-1964) was an important figure in 20th century hydrology and one of the pioneers of scientific water gauging in Europe. His research on the reliability of hydrological data and measurement methods was particularly important and contributed to the development of empirical hydrological calculation methods. Kolupaila was one of the first who standardised water-gauging methods internationally. He created several original hydrological and hydraulic calculation methods (his discharge assessment method for winter period was particularly significant). His innate abilities and frequent travel made Kolupaila a universal specialist in various fields and an active public figure. He revealed his multilayered scientific and cultural experiences in his most famous book, Bibliography of Hydrometry. This book introduced the unique European hydrological-measurement and computation methods to the community of world hydrologists at that time and allowed the development and adaptation of these methods across the world.

A radial time projection chamber for α detection in CLAS at JLab

DOE PAGES

Dupre, R.; Stepanyan, S.; Hattawy, M.; ...

2018-08-01

A new Radial Time Projection Chamber (RTPC) was developed at the Jefferson Laboratory to track low-energy nuclear recoils to measure exclusive nuclear reactions, such as coherent deeply virtual Compton scattering and coherent meson production off 4He. In 2009, we carried out these measurements using the CEBAF Large Acceptance Spectrometer (CLAS) supplemented by the RTPC positioned directly around a gaseous 4He target, allowing a detection threshold as low as 12 MeV for 4He. This work discusses the design, principle of operation, calibration methods and performances of this RTPC.

A radial time projection chamber for α detection in CLAS at JLab

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

Dupre, R.; Stepanyan, S.; Hattawy, M.

A new Radial Time Projection Chamber (RTPC) was developed at the Jefferson Laboratory to track low-energy nuclear recoils to measure exclusive nuclear reactions, such as coherent deeply virtual Compton scattering and coherent meson production off 4He. In 2009, we carried out these measurements using the CEBAF Large Acceptance Spectrometer (CLAS) supplemented by the RTPC positioned directly around a gaseous 4He target, allowing a detection threshold as low as 12 MeV for 4He. This work discusses the design, principle of operation, calibration methods and performances of this RTPC.

Mentored and inspired by Mimo: a tribute to Erminio Costa.

PubMed

Bloom, Floyd E

2011-06-01

Throughout his long productive scientific career, Erminio Costa demonstrated several scholarly traits that illustrate a pattern for paths of successful achievement that should guide young scientists. Not only did he seek excellent training, he got and gave good mentoring. That guidance allowed him to ask important questions and to develop the methods necessary to obtain definitive answers by pursuing those questions in depth. Without question, he blazed trails in neuropharmacology that have been an inspiration to many others and me. This article is part of a Special Issue entitled 'Trends in neuropharmacology: in memory of Erminio Costa'.

Science and Society Colloquium

ScienceCinema

None

2017-12-09

Mr. Randi will give an update of his lecture to the American Physical Society on the occasion of his award of the 1989 Forum Prize. The citation said: "for his unique defense of Science and the scientific method in many disciplines, including physics, against pseudoscience, frauds and charlatans. His use of scientific techniques has contributed to refuting suspicious and fraudulent claims of paranormal results. He has contributed significantly to public understanding of important issues where science and society interact". He is a professional magician and author of many books. He worked with John Maddox, the Editor of Nature to investigate the claims of "water with memory".

[The role of Hunayn, physician and translator].

PubMed

Habbi, J

1994-01-01

Hunayn ibn Ishāq is one of the most important translators of scientific and medical texts in the 'abbāsid era. He played a fundamental role in the transmission of Greek medical science to the Arab world, because of his deep knowledge of the Syriac, Arabic and Persian languages. He translated about 300 texts, especially medical ones, and he founded a school in which many disciples were instructed in the art of translation, like his son Ishāq and his nephew Hubays. Hunayn composed a lexicon of scientific terminology, using a new method of translation which represents his great innovation.

Using design methods to provide the care that people want and need.

PubMed

Erwin, Kim; Krishnan, Jerry A

2016-01-01

Kim Erwin is an Assistant Professor at IIT Institute of Design and trained in user-centered design methods, which put people at the center of any problem space so as to develop solutions that better fit their everyday lives, activities and context. Her expertise is in making complex information easier to understand and use. Her research targets communication tools and methods for collaborative knowledge construction built through shared experiences. Her book, Communicating the New: Methods to shape and accelerate innovation focuses on helping teams explore, build and diffuse critical knowledge inside organizations. Jerry Krishnan is a Professor of Medicine and Public Health, and Associate Vice President for Population Health Sciences at the University of Illinois Hospital & Health Sciences System. He pioneered the use of Analytic Hierarchy Process to elicit the expressed needs of stakeholders for research. He previously served as Chair of the US FDA Pulmonary and Allergy Drugs Advisory Committee and is a Principal Investigator in NIH and Patient Centered Outcomes Research Institute (PCORI)-funded research consortia. He chairs the US National Heart, Lung, and Blood Institute (NHLBI) Clinical Trials review committee and the PCORI Improving Healthcare Systems merit review panel.

The medical life of Henry Norman Bethune

PubMed Central

Deslauriers, Jean; Goulet, Denis

2015-01-01

BACKGROUND: Henry Norman Bethune is one of the most exciting and incredible surgeons that Canada has ever produced. Indeed, he is often characterized as one of the world’s best-known surgeons. He was an innovator and his scientific contributions have stood the test of time. In Canada, he will forever be remembered as a social activist committed to the welfare of the poor and to the reform of the health care system. In the People’s Republic of China, he is idolized and remains the only foreigner to ever become a national hero. OBJECTIVE: To detail the numerous and significant achievements of Henry Norman Bethune in the field of thoracic surgery and as a social activist and describe his heroic war-time actions on the battlefields of both Spain and China. METHOD: Information was gathered through the reading of the numerous publications written about the life and work of Bethune, interviews with knowledgeable people from Canadian and Chinese universities, analysis of Bethune’s own publications, and extensive experience of one of the authors in China. RESULTS: In the social sense, Henry Norman Bethune had a difficult personality, but he was deeply caring about the plight of his patients, especially the poor. As a thoracic surgeon, he could be ingenious, thoughtful and effective but he could also be abrasive, restless and temperamental. His scientific contributions were sound and, at the time, gained worldwide attention. As an activist, he led a crusade to reform the Canadian health care system, demanding free health care for all. His outstanding work during the Spanish Civil War, where he organized the first ever mobile blood transfusion unit, and during the Sino-Japanese war, where he was totally committed to the welfare of both soldiers and civilian population, were deliberate acts of resistance against Fascist onslaught and enthusiasm for the Communist cause. CONCLUSIONS: Henry Norman Bethune was unconventional and a revolutionary, but he was brilliant. He will forever be remembered as an innovative thoracic surgeon and outstanding humanitarian.

Insight into He diffusion in apatite by ion beam experiments and quantum calculations: implication for the (U-Th)/He thermochronometer

NASA Astrophysics Data System (ADS)

Gautheron, C.; Mbongo-Djimbi, D.; Gerin, C.; Roques, J.; Bachelet, C.; Oliviero, E.; Tassan-Got, L.

2015-12-01

The apatite (U-Th)/He (AHe) system has rapidly become a very popular thermochronometer, however, interpretation of AHe age depends on a precise knowledge of He diffusion. Several studies suggest that He retention is function of the amount of damage that is controlled by U-Th concentration, grain chemistry and thermal history. Still, the models are not well constrained and do not fully explain the mechanism of He retention. In order to have a deeper insight into this issue, a multidisciplinary study on apatite combining physical methods such as multi-scale theoretical diffusion calculations based on Density Functional Theory (DFT) with diffusion experiments by ion beam Elastic Recoil Diffusion Analysis (ERDA) were performed. Quantum calculations permit to quantify He diffusivity base level for damage-free crystal and to estimate the additional energy cost to extract He atoms trapped in point defects (i.e. vacancies). On the other hand ion beam ERDA experiments allow to measure He diffusivity in artificially damaged crystals. We show that damage-free apatite crystals are characterized by low retention behavior and closure temperature of ~35°C for pure F-apatite to higher value for Cl rich apatite (up to 12°C higher), for typical grain size and cooling rate (Mbongo-Djimbi et al., 2015). Our computed closure temperature is slightly lower than previously reported experimental values (~50°C). Using ERDA and DFT modeling of damage, we show how He diffusivity is influenced by damage. Finally, we are able to propose a new modeling of He diffusion incorporating mechanisms not included in classical damage models, and taking into account the level of damage and apatite chemistry. We show that it could affect significantly AHe age interpretation. Mbongo-Djimbi D. et al. 2015. Apatite composition effect on (U-Th)/He thermochronometer: an atomistic point of view. Geohimica Cosmochim. Acta.

Excited states of 4He

NASA Astrophysics Data System (ADS)

Aoyama, Shigeyoshi

2013-04-01

The study of the 4He nucleus is important because it is the most basic sub-unit (cluster) in nuclei. We have investigated the structures and the reaction mechanisms in 4He by using the correlated Gaussian basis function with the global vector representation. In order to treat the boundary condition for the ab-initio calculation of the four nucleons, we employ the Microscopic R-matrix Method (MRM) and the Complex Scaling Method (CSM) . Elastic-scattering phase shifts for four-nucleon systems are studied in an ab-initio type cluster model with MRM in order to clarify the role of the tensor force and to investigate cluster distortions in low energy d+d and t+p scattering. For 1S0, the calculated phase shifts show that the t+p and h+n channels are strongly coupled to the d+d channel for the case of the realistic interaction.

Soviet-West German Symposium on Heat Transfer in Cryogenic Systems, 3rd, Kharkov, Ukrainian SSR, Oct. 9-11, 1989, Proceedings

NASA Astrophysics Data System (ADS)

1990-04-01

The papers presented in this volume describe a rotating cryostat for the simulation of mechanical, thermal, and hydraulic processes in superconducting rotors; the problems of cooling the fully superconducting generator stator; an investigation of natural circulation by optical methods; and a method of calculating void fraction for vapor-liquid or gas-liquid flow conditions. Attention is given to an experimental study of the processes of He-3 boiling and condensation, heat transfer in He II at a slow variation of the heat load, an investigation of He II flow crisis in porous media, and cryogenic heat pipes. Other papers are on the stability of rotating superconducting windings for electric machines, the stability of high-temperature superconductors cooled by liquid nitrogen, a calculation of the transpiration cooling of a cylindrical porous wall, and pressure losses in boiling nitrogen flow through horizontal channels.

Asymptotic Energies and QED Shifts for Rydberg States of Helium

NASA Technical Reports Server (NTRS)

Drake, G.W.F.

2007-01-01

This paper reviews progress that has been made in obtaining essentially exact solutions to the nonrelativistic three-body problem for helium by a combination of variational and asymptotic expansion methods. The calculation of relativistic and quantum electrodynamic corrections by perturbation theory is discussed, and in particular, methods for the accurate calculation of the Bethe logarithm part of the electron self energy are presented. As an example, the results are applied to the calculation of isotope shifts for the short-lived 'halo' nucleus He-6 relative to He-4 in order to determine the nuclear charge radius of He-6 from high precision spectroscopic measurements carried out at the Argonne National Laboratory. The results demonstrate that the high precision that is now available from atomic theory is creating new opportunities to create novel measurement tools, and helium, along with hydrogen, can be regarded as a fundamental atomic system whose spectrum is well understood for all practical purposes.

Optical Pumping Spin Exchange 3He Gas Cells for Magnetic Resonance Imaging

NASA Astrophysics Data System (ADS)

Kim, W.; Stepanyan, S. S.; Kim, A.; Jung, Y.; Woo, S.; Yurov, M.; Jang, J.

2009-08-01

We present a device for spin-exchange optical pumping system to produce large quantities of polarized noble gases for Magnetic Resonance Imaging (MRI). A method and design of apparatus for pumping the polarization of noble gases is described. The method and apparatus enable production, storage and usage of hyperpolarized noble gases for different purposes, including Magnetic Resonance Imaging of human and animal subjects. Magnetic imaging agents breathed into lungs can be observed by the radio waves of the MRI scanner and report back physical and functional information about lung's health and desease. The technique known as spin exchange optical pumping is used. Nuclear magnetic resonance is implemented to measure the polarization of hyperpolarized gas. The cells prepared and sealed under high vacuum after handling Alkali metals into the cell and filling with the 3He-N2 mixture. The cells could be refilled. The 3He reaches around 50% polarization in 5-15 hours.

James F. McGinnis, D.C., N.D., C.P. (1873-1947): spinographer, educator, marketer and bloodless surgeon.

PubMed

Keating, J C

1998-12-01

Perhaps best remembered for his contributions to B.J. Palmer's earliest developments in spinography, James F. McGinnis also pioneered in marketing methods while a straight chiropractic practitioner in Iowa. His advertising brought him to the attention of organized medicine, which sought his prosecution. Relocating to California in the early 1920s, he broadened his scope of practice and earned a naturopathic doctorate. In the 1930s he became one of the best known of several chiropractic bloodless surgeons and traveled around the nation to teach his methods. Although initially a passionate member of the Universal Chiropractors Association and receptive to Palmer's introduction of the neurocalometer, McGinnis eventually changed his political allegiance and became an active member of the National Chiropractic Association. He died in 1947 while on a teaching tour of Claifornia's San Joaquin Valley.

Combined antitumor activity of the nitroreductase/CB1954 suicide gene system and γ-rays in HeLa cells in vitro

PubMed Central

Teng, Geling; Ju, Yuanrong; Yang, Yepeng; Hua, Hu; Chi, Jingyu; Mu, Xiuan

2016-01-01

Escherichia coli nitroreductase (NTR) may convert the prodrug CB1954 (5-(aziridin-1-yl)-2,4-dinitrobenzamide) into a bifunctional alkylating agent, which may lead to DNA crosslinks and the apoptosis of cancer cells. NTR/CB1954 has been demonstrated to be an effective gene therapy in cancer cells. The present study examined whether the NTR/CB1954 suicide gene system had cytotoxic effects on HeLa cells and may improve the radiosensitivity of HeLa cells to γ-rays. It was observed that the NTR/CB1954 suicide gene system exerted marked cytotoxic effects on HeLa cells. The combined therapeutic effects of NTR/CB1954 and γ-rays on HeLa cells demonstrated a synergistic effect. CB1954 at concentrations of 12.5 and 25 µmol/l increased the sensitization enhancement ratio of HeLa cells to 1.54 and 1.66, respectively. Therefore, when compared with monotherapy, the combined therapy of NTR/CB1954 and γ-rays may increase the apoptotic rate and enhance the radiosensitivity of HeLa cells. The combined therapy of γ-ray radiation and the NTR/CB1954 suicide gene system may be a novel and potent therapeutic method for the treatment of cervical carcinoma. PMID:27840931

Combined antitumor activity of the nitroreductase/CB1954 suicide gene system and γ-rays in HeLa cells in vitro.

PubMed

Teng, Geling; Ju, Yuanrong; Yang, Yepeng; Hua, Hu; Chi, Jingyu; Mu, Xiuan

2016-12-01

Escherichia coli nitroreductase (NTR) may convert the prodrug CB1954 (5-(aziridin-1-yl)-2,4-dinitrobenzamide) into a bifunctional alkylating agent, which may lead to DNA crosslinks and the apoptosis of cancer cells. NTR/CB1954 has been demonstrated to be an effective gene therapy in cancer cells. The present study examined whether the NTR/CB1954 suicide gene system had cytotoxic effects on HeLa cells and may improve the radiosensitivity of HeLa cells to γ‑rays. It was observed that the NTR/CB1954 suicide gene system exerted marked cytotoxic effects on HeLa cells. The combined therapeutic effects of NTR/CB1954 and γ‑rays on HeLa cells demonstrated a synergistic effect. CB1954 at concentrations of 12.5 and 25 µmol/l increased the sensitization enhancement ratio of HeLa cells to 1.54 and 1.66, respectively. Therefore, when compared with monotherapy, the combined therapy of NTR/CB1954 and γ‑rays may increase the apoptotic rate and enhance the radiosensitivity of HeLa cells. The combined therapy of γ‑ray radiation and the NTR/CB1954 suicide gene system may be a novel and potent therapeutic method for the treatment of cervical carcinoma.

3He NMR studies on helium-pyrrole, helium-indole, and helium-carbazole systems: a new tool for following chemistry of heterocyclic compounds.

PubMed

Radula-Janik, Klaudia; Kupka, Teobald

2015-02-01

The (3)He nuclear magnetic shieldings were calculated for free helium atom and He-pyrrole, He-indole, and He-carbazole complexes. Several levels of theory, including Hartree-Fock (HF), Second-order Møller-Plesset Perturbation Theory (MP2), and Density Functional Theory (DFT) (VSXC, M062X, APFD, BHandHLYP, and mPW1PW91), combined with polarization-consistent pcS-2 and aug-pcS-2 basis sets were employed. Gauge-including atomic orbital (GIAO) calculated (3)He nuclear magnetic shieldings reproduced accurately previously reported theoretical values for helium gas. (3)He nuclear magnetic shieldings and energy changes as result of single helium atom approaching to the five-membered ring of pyrrole, indole, and carbazole were tested. It was observed that (3)He NMR parameters of single helium atom, calculated at various levels of theory (HF, MP2, and DFT) are sensitive to the presence of heteroatomic rings. The helium atom was insensitive to the studied molecules at distances above 5 Å. Our results, obtained with BHandHLYP method, predicted fairly accurately the He-pyrrole plane separation of 3.15 Å (close to 3.24 Å, calculated by MP2) and yielded a sizable (3)He NMR chemical shift (about -1.5 ppm). The changes of calculated nucleus-independent chemical shifts (NICS) with the distance above the rings showed a very similar pattern to helium-3 NMR chemical shift. The ring currents above the five-membered rings were seen by helium magnetic probe to about 5 Å above the ring planes verified by the calculated NICS index. Copyright © 2014 John Wiley & Sons, Ltd.

The Immunohistochemistry and Toluidine Blue Roles for Helicobacter pylori Detection in Patients with Gastritis

PubMed Central

Tajalli, Raziye; Nobakht, Maliheh; Mohammadi-Barzelighi, Hajar; Agah, Shahram; Rastegar-Lari, Abdolaziz; Sadeghipour, Alireza

2013-01-01

Background: Helicobacter pylori, which is associated with many upper gastrointestinal diseases, is found in half of the population of the world. Several special stains and immunohistochemistry stain for H. pylori are available. The need for and usefulness of immunohistochemical (IHC) technique has been debated for years. Toluidine blue is a simple stain for microbiological studies and is easily available in laboratories. Therefore, this study was conducted to compare hematoxylin and eosin (H&E), Giemsa and toluidine blue staining with immunehistochemistry for detection of H. pylori in patients with gastritis and also to correlate the results of these staining methods with pathological grading. Methods: We reviewed 54 consecutive gastric biopsy specimens stained by H&E and Giemsa as well as by toluidine blue and immunohistochemistry stains for H. pylori. Results: H. pylori was positively identified by IHC in 43 (79.63%) patients, while positive samples were found in 18 (33.33%), 24 (44.44%) and 33 (61.11%) patients using H&E, Giemsa and toluidine blue staining methods. Our results showed that classical histological staining methods are not sensitive enough to identify low numbers or coccoid forms of organism, while toluidine blue and immunohistochemistry play an important role in detection of H. pylori infection. Conclusion: Toluidine blue has been proved to be much more reliable than H&E and Giemsa in detection of H. pylori. In addition, in post treatment biopsies and in biopsies with unexplained chronic active gastritis without histological evidence of H. pylori should have immunohistochemistry done to detect possible low density or coccoid form of organisms. PMID:23279833

Inert gas annealing effect in solution-processed amorphous indium-gallium-zinc-oxide thin-film transistors

NASA Astrophysics Data System (ADS)

Lee, Seungwoon; Jeong, Jaewook

2017-08-01

In this paper, the annealing effect of solution-processed amorphous indium-gallium-zinc-oxide thin-film transistors (a-IGZO TFTs), under ambient He (He-device), is systematically analyzed by comparison with those under ambient O2 (O2-device) and N2 (N2-device), respectively. The He-device shows high field-effect mobility and low subthreshold slope owing to the minimization of the ambient effect. The degradation of the O2- and N2-device performances originate from their respective deep acceptor-like and shallow donor-like characteristics, which can be verified by comparison with the He-device. However, the three devices show similar threshold voltage instability under prolonged positive bias stress due to the effect of excess oxygen. Therefore, annealing in ambient He is the most suitable method for the fabrication of reference TFTs to study the various effects of the ambient during the annealing process in solution-processed a-IGZO TFTs.

Wittgenstein's neurophenomenology.

PubMed

Cole, J

2007-06-01

Wittgenstein, despite being considered an analytical philosopher, has been quoted extensively by neurologists like Oliver Sacks. This paper explores how Wittgenstein, despite suggesting that science was antithetical to philosophy, made observations relevant to cognitive neuroscience. His work on the inner and the outer, the relation between language and sensation or perception, and on the embodied nature of emotion and its communication, is important for an understanding of neurological impairment beyond our experience. In some of his enigmatic short writing his insights are pertinent to patients' experience, say of pain, Capgras' Syndrome and spinal cord injury. He also made observations on movement sense, will and action. He did not engage in empirical science, nor obtain data in any conventional sense. But his genius was not confined to abstract philosophy. His powers of observation and introspection led him to explore lived experience in new ways, some of which are only now being approached empirically. The method of science, he once wrote, leads philosophy into complete darkness. Had he lived today, one hopes that even he might have changed his mind.

Extension of the Haseman-Elston regression model to longitudinal data.

PubMed

Won, Sungho; Elston, Robert C; Park, Taesung

2006-01-01

We propose an extension to longitudinal data of the Haseman and Elston regression method for linkage analysis. The proposed model is a mixed model having several random effects. As response variable, we investigate the sibship sample mean corrected cross-product (smHE) and the BLUP-mean corrected cross product (pmHE), comparing them with the original squared difference (oHE), the overall mean corrected cross-product (rHE), and the weighted average of the squared difference and the squared mean-corrected sum (wHE). The proposed model allows for the correlation structure of longitudinal data. Also, the model can test for gene x time interaction to discover genetic variation over time. The model was applied in an analysis of the Genetic Analysis Workshop 13 (GAW13) simulated dataset for a quantitative trait simulating systolic blood pressure. Independence models did not preserve the test sizes, while the mixed models with both family and sibpair random effects tended to preserve size well. Copyright 2006 S. Karger AG, Basel.

Sir Edward Mellanby (1884-1955) GBE KCB FRCP FRS: nutrition scientist and medical research mandarin.

PubMed

Hawgood, Barbara J

2010-08-01

Edward Mellanby used the experimental method to investigate medical problems. In 1918, working at King's College for Women, London, he provided conclusive evidence that rickets is a dietary deficiency disease due to lack of a fat-soluble vitamin [D]. In Sheffield he demonstrated that cereals, in an unbalanced diet, produced rickets due to the phytic acid content reducing the availability of calcium. Mellanby became Secretary of the Medical Research Council (1933-49) but continued his research by working at weekends. In the 1930s he campaigned for the results of nutritional research to be used for the benefit of public health. During World War II he acted as a scientific adviser to the War Cabinet and had a strong influence on the food policy which maintained successfully the nutrition of the population during the shipping blockade. Mellanby was a formidable person but with sagacity he promoted new research and guided the expansion of the organization.

Spin exchange optical pumping based polarized 3He filling station for the Hybrid Spectrometer at the Spallation Neutron Source.

PubMed

Jiang, C Y; Tong, X; Brown, D R; Culbertson, H; Graves-Brook, M K; Hagen, M E; Kadron, B; Lee, W T; Robertson, J L; Winn, B

2013-06-01

The Hybrid Spectrometer (HYSPEC) is a new direct geometry spectrometer at the Spallation Neutron Source at the Oak Ridge National Laboratory. This instrument is equipped with polarization analysis capability with 60° horizontal and 15° vertical detector coverages. In order to provide wide angle polarization analysis for this instrument, we have designed and built a novel polarized (3)He filling station based on the spin exchange optical pumping method. It is designed to supply polarized (3)He gas to HYSPEC as a neutron polarization analyzer. In addition, the station can optimize the (3)He pressure with respect to the scattered neutron energies. The depolarized (3)He gas in the analyzer can be transferred back to the station to be repolarized. We have constructed the prototype filling station. Preliminary tests have been carried out demonstrating the feasibility of the filling station. Here, we report on the design, construction, and the preliminary results of the prototype filling station.

Importance of helium-3 for the future

NASA Technical Reports Server (NTRS)

Kulcinski, Gerald L.

1989-01-01

Relevant plasma physics principles of thermonuclear research; the state of plasma physics as it pertains to the D-He(3) cycle; the technological benefits of the D-He(3) fuel cycle; the availability of He(3); and its location, methods of extraction and cost are discussed. A perspective on the rate of progress toward the goal of heating the confined plasma fuel to sufficiently high temperatures at high enough densities and for long enough times to cause substantial fusion of the atoms to take place is given in graphical form. The main technological advantages resulting from the D-He(3) fuel cycle, when compared with the DT cycle, are as follows: (1) increased electrical conversion efficiency; (2) reduced radiation damage to reactors; (3) reduced radioactive waste; (4) an increased level of safety in case of an accident; (5) the lower cost of electricity; and (6) the shorter time to commercialization. An account is given of mining He(3) on the Moon.

[Emil Kraepelin: a pioneer of modern psychiatry. On the occasion of the hundred and fiftieth anniversary of his birth].

PubMed

Géraud, M

2007-09-01

Emil Kraepelin (1856-1926) whose hundred and fiftieth birth anniversary we are celebrating this year, is one of the most renowned figures of psychiatry. His Memoirs published in 1983 provide insight on the individual. In his early career he lived in Würzburg, Munich, Leipzig, Leubus, Dresden, and then in Dorpat in 1886 (as visiting professor) where he stayed for five years, in Heidelberg (as regular professor) from 1891 to 1904, and lastly in Munich. Kraepelin ranks among the great clinical medicine forerunners who followed in Kahlbaum's footsteps. For him, the foremost task of scientific psychiatry was to circumscribe pathological entities. At the foundation of Kraepelin-inspired scientific psychiatry lies the notion of the of disease, as opposed to the approach (5th edition of the Treatise), whereby it is no longer concerned with the study of mental disorder in terms of symptoms but rather in terms of conditions of occurrence, evolution and outcome thereof. This method produced two well-known results: the unification and recognition of , and the definition of (dementia praecox). These results are described in the Treatise of Psychiatry which has had eight editions during the author's lifetime (from 1883 to 1915), and which presents Kraepelin's systematic nosography covering the entire field of mental illness. Such an innovative method required special tools capable of exploring not only the symptoms, as had been done previously, but the pathological process per se: therefore, Kreapelin created a systematic method to conduct psychiatric research and founded a Research Establishment divided into different sections (histopathology, topographic histology, serology, genealogy). Alois Alzheimer and Franz Nissl, among others, were closely associated with his work. Kreapelin's thought was not set, however, and by the end of his career it took a turn toward a more comprehensive type of psychiatry (1920) taking into account the social aspects (). From the therapeutic and institutional viewpoints, Kraepelin remained faithful throughout his life to the no-restraint practice by abolishing any restraint methods wherever he worked; by establishing a trust-based relationship with the patients; by allowing the patients to correspond and by opening the institution to visitors. Additionally, he participated actively in the struggle against alcoholism and syphilis. He is also one of the initiators of cross-cultural psychiatry (). Although he lead a medical career, Kraepelin was also interested in experimental psychology, and he thought of his works in that area as more important than his clinical achievements. He was closely connected with Wilhelm Wundt with whom he worked (at the Institute of Psychology of Leipzig where Kraepelin was one of the first medical doctors to collaborate with Wundt) and then exchanged letters. Some of his experimental works, including the elaboration of series of tests aimed at studying the psychic effects of certain substances, herald the advent of psychopharmacology. Lastly, his Memoirs and Poems give insight on the intimate person of Kraepelin, as well as putting his affective life in perspective.

Comparison of two heuristic evaluation methods for evaluating the usability of health information systems.

PubMed

Khajouei, Reza; Hajesmaeel Gohari, Sadrieh; Mirzaee, Moghaddameh

2018-04-01

In addition to following the usual Heuristic Evaluation (HE) method, the usability of health information systems can also be evaluated using a checklist. The objective of this study is to compare the performance of these two methods in identifying usability problems of health information systems. Eight evaluators independently evaluated different parts of a Medical Records Information System using two methods of HE (usual and with a checklist). The two methods were compared in terms of the number of problems identified, problem type, and the severity of identified problems. In all, 192 usability problems were identified by two methods in the Medical Records Information System. This was significantly higher than the number of usability problems identified by the checklist and usual method (148 and 92, respectively) (p < 0.0001). After removing the duplicates, the difference between the number of unique usability problems identified by the checklist method (n = 100) and usual method (n = 44) was significant (p < 0.0001). Differences between the mean severity of the real usability problems (1.83) and those identified by only one of the methods (usual = 2.05, checklist = 1.74) were significant (p = 0.001). This study revealed the potential of the two HE methods for identifying usability problems of health information systems. The results demonstrated that the checklist method had significantly better performance in terms of the number of identified usability problems; however, the performance of the usual method for identifying problems of higher severity was significantly better. Although the checklist method can be more efficient for less experienced evaluators, wherever usability is critical, the checklist should be used with caution in usability evaluations. Copyright © 2018 Elsevier Inc. All rights reserved.

Finding the "A-Ha" Moment: An Exploration into HE in FE Teacher Self-Concept

ERIC Educational Resources Information Center

Kadi-Hanifi, Karima; Keenan, John

2016-01-01

Five teachers of higher education (HE)-level courses working in the further education (FE) sector recalled critical moments which helped to form their self-concepts. The researchers used life history method to encourage the teachers to be open about their lives and how they formed their personal and professional selves. Three common themes were…

Exact solitary wave solution for higher order nonlinear Schrodinger equation using He's variational iteration method

NASA Astrophysics Data System (ADS)

Rani, Monika; Bhatti, Harbax S.; Singh, Vikramjeet

2017-11-01

In optical communication, the behavior of the ultrashort pulses of optical solitons can be described through nonlinear Schrodinger equation. This partial differential equation is widely used to contemplate a number of physically important phenomena, including optical shock waves, laser and plasma physics, quantum mechanics, elastic media, etc. The exact analytical solution of (1+n)-dimensional higher order nonlinear Schrodinger equation by He's variational iteration method has been presented. Our proposed solutions are very helpful in studying the solitary wave phenomena and ensure rapid convergent series and avoid round off errors. Different examples with graphical representations have been given to justify the capability of the method.

4He+n+n continuum within an ab initio framework

DOE PAGES

Romero-Redondo, Carolina; Quaglioni, Sofia; Navratil, Petr; ...

2014-07-16

In this study, the low-lying continuum spectrum of the 6He nucleus is investigated for the first time within an ab initio framework that encompasses the 4He+n+n three-cluster dynamics characterizing its lowest decay channel. This is achieved through an extension of the no-core shell model combined with the resonating-group method, in which energy-independent nonlocal interactions among three nuclear fragments can be calculated microscopically, starting from realistic nucleon-nucleon interactions and consistent ab initio many-body wave functions of the clusters. The three-cluster Schrödinger equation is solved with three-body scattering boundary conditions by means of the hyperspherical-harmonics method on a Lagrange mesh. Using amore » soft similarity-renormalization-group evolved chiral nucleon-nucleon potential, we find the known J π = 2 + resonance as well as a result consistent with a new low-lying second 2 + resonance recently observed at GANIL at ~2.6 MeV above the He6 ground state. We also find resonances in the 2 –, 1 +, and 0 – channels, while no low-lying resonances are present in the 0 + and 1 – channels.« less

[The first three Nordic Nobel laureates in physiology or medicine].

PubMed

Pernow, B

1997-01-01

Among all the Nobel Laureates in physiology or medicine there are five from Denmark and seven from Sweden. The first three Laureates are presented in this paper. Over 50 years have elapsed since they were awarded and the Nobel archives are now open for scrutiny, providing insight into how the Nobel committee interpreted the instruction given in Nobel's will at that time. Niels Finsen (1860-1904, Nobel Laureate 1903) devoted his short life to a continuous study of the biological effects of sunshine, which resulted in a method aimed at utilizing the bacteriocide properties of sun rays in the treatment of various skin diseases and especially tuberculosis. Finsen published his first paper on this topic in 1896 and his method revolutionized the current treatment of this disease. Approximately forty Finsen Institutes were established in Europe and the USA within the subsequent five years. Alvar Gullstrand (1869-1930, Nobel Laureate 1911) was an ophthalmologist but his main interest was mathematical physics, where he achieved results of utmost importance for clinical opthalmology. He systematically studied the optical system, from the physical properties of light rays to optimal images in different media of the eye. He formulated general laws if image, which he extrapolated to the human eye. He also devised several techniques, some of which still used in ophthalmology. August Krogh (1874-1949, Nobel Laureate 1920) was a zoological physiologist, actively involved in various fields, including human muscle physiology and metabolism, capillary circulation in the frog, water regulation in the desert rat and the jumping capacity of the grasshopper. He was the founder of modern human exercise physiology and sport medicine. Krogh received the Nobel prize the year after he published his first paper on the regulation of the motor activity of capillaries, which reflected the Nobel committee's desire at that time to support a young scientist in the most successul period of his career. Through his continuous brilliant research during three decades Krogh eminently demonstrated that the committee had indeed use far-sighted judgement.

Comparison of image quality, myocardial perfusion, and LV function between standard imaging and single-injection ultra-low-dose imaging using a high-efficiency SPECT camera: the MILLISIEVERT study

PubMed Central

Einstein, Andrew J.; Blankstein, Ron; Andrews, Howard; Fish, Mathews; Padgett, Richard; Hayes, Sean W.; Friedman, John D.; Qureshi, Mehreen; Rakotoarivelo, Harivony; Slomka, Piotr; Nakazato, Ryo; Bokhari, Sabahat; Di Carli, Marcello; Berman, Daniel S.

2015-01-01

SPECT myocardial perfusion imaging (MPI) plays a central role in coronary artery disease diagnosis; but concerns exist regarding its radiation burden. Compared to standard Anger-SPECT (A-SPECT) cameras, new high-efficiency (HE) cameras with specialized collimators and solid-state cadmium-zinc-telluride detectors offer potential to maintain image quality (IQ), while reducing administered activity and thus radiation dose to patients. No previous study has compared IQ, interpretation, total perfusion deficit (TPD), or ejection fraction (EF) in patients receiving both ultra-low-dose (ULD) imaging on a HE-SPECT camera and standard low-dose (SLD) A-SPECT imaging. Methods We compared ULD-HE-SPECT to SLD-A-SPECT imaging by dividing the rest dose in 101 patients at 3 sites scheduled to undergo clinical A-SPECT MPI using a same day rest/stress Tc-99m protocol. Patients received HE-SPECT imaging following an initial ~130 MBq (3.5mCi) dose, and SLD-A-SPECT imaging following the remainder of the planned dose. Images were scored visually by 2 blinded readers for IQ and summed rest score (SRS). TPD and EF were assessed quantitatively. Results Mean activity was 134 MBq (3.62 mCi) for ULD-HE-SPECT (effective dose 1.15 mSv) and 278 MBq (7.50 mCi, 2.39 mSv) for SLD-A-SPECT. Overall IQ was superior for ULD-HE-SPECT (p<0.0001), with twice as many studies graded excellent quality. Extracardiac activity and overall perfusion assessment were similar. Between-method correlations were high for SRS (r=0.87), TPD (r=0.91), and EF (r=0.88). Conclusion ULD-HE-SPECT rest imaging correlates highly with SLD-A-SPECT. It has improved image quality, comparable extracardiac activity, and achieves radiation dose reduction to 1 mSv for a single injection. PMID:24982439

Gambling scores for earthquake predictions and forecasts

NASA Astrophysics Data System (ADS)

Zhuang, Jiancang

2010-04-01

This paper presents a new method, namely the gambling score, for scoring the performance earthquake forecasts or predictions. Unlike most other scoring procedures that require a regular scheme of forecast and treat each earthquake equally, regardless their magnitude, this new scoring method compensates the risk that the forecaster has taken. Starting with a certain number of reputation points, once a forecaster makes a prediction or forecast, he is assumed to have betted some points of his reputation. The reference model, which plays the role of the house, determines how many reputation points the forecaster can gain if he succeeds, according to a fair rule, and also takes away the reputation points betted by the forecaster if he loses. This method is also extended to the continuous case of point process models, where the reputation points betted by the forecaster become a continuous mass on the space-time-magnitude range of interest. We also calculate the upper bound of the gambling score when the true model is a renewal process, the stress release model or the ETAS model and when the reference model is the Poisson model.

Microbiological Spoilage of Canned Foods

NASA Astrophysics Data System (ADS)

Evancho, George M.; Tortorelli, Suzanne; Scott, Virginia N.

Nicolas Appert (1749-1841) developed the first commercial process that kept foods from spoiling in response to an offer from the French government for a method of preserving food for use by the army and navy. Appert, a confectioner and chef, began to experiment in his workshop in Massy, near Paris, but since little was known about bacteriology and the causes of spoilage (Louis Pasteur had yet to formulate the germ theory), much of his work involved trial and error. In 1810, after years of experimenting, he was awarded the prize of 12,000 francs for his method of preservation, which involved cooking foods in sealed jars at high temperatures. He described his method of preserving food in a book published in 1811, "L'Art De Conserver, Pendant Plusiers Annes, Toutes les Substances Animales et Végétales," which translated means "The Art of Preserving All Kinds of Animal and Vegetable Substances for Several Years." He later built a bottling factory and began to produce preserved foods for the people of France and is credited with being the "Father of Canning."

Prolonged remission from hepatic encephalopathy with rifaximin: results of a placebo crossover analysis

PubMed Central

Bajaj, J S; Barrett, A C; Bortey, E; Paterson, C; Forbes, W P

2015-01-01

Background Rifaximin therapy reduced risk of hepatic encephalopathy (HE) recurrence and HE-related hospitalisations during a 6-month, randomised, placebo-controlled trial (RCT) and a 24-month open-label maintenance (OLM) study. However, the impact of crossover from placebo to rifaximin therapy is unclear. Aim To study the impact of crossing over from placebo to rifaximin treatment on breakthrough HE and hospitalisation rates using a within-subjects design. Methods Adults with cirrhosis and history of overt HE episodes, currently in HE remission, received placebo during the RCT and crossed over to rifaximin 550 mg twice daily during the OLM study. Rate of breakthrough overt HE episodes, hospitalisations and incidence and rate of adverse events (AEs) were analysed during RCT and first 6 months of OLM. Results Of 82 patients randomised to placebo in the RCT who crossed over to the OLM study, 39 experienced an HE episode during the RCT compared with 14 during the OLM study (P < 0.0001). Significantly lower rates of HE events were observed with rifaximin treatment compared with placebo treatment (P < 0.0001). Rates of HE-related hospitalisation were numerically lower during rifaximin treatment compared with placebo treatment, although not significant. Rates of most common AEs, serious AEs and infection-related AEs were similar between the two treatments. Conclusions This analysis confirms the repeatability of results from the RCT on safety and efficacy of rifaximin 550 mg twice daily in reducing the risk of hepatic encephalopathy recurrence, and suggests these findings are translatable outside of a rigorous, controlled trial setting. PMID:25339518

Enabling Histopathological Annotations on Immunofluorescent Images through Virtualization of Hematoxylin and Eosin

PubMed Central

Lahiani, Amal; Klaiman, Eldad; Grimm, Oliver

2018-01-01

Context: Medical diagnosis and clinical decisions rely heavily on the histopathological evaluation of tissue samples, especially in oncology. Historically, classical histopathology has been the gold standard for tissue evaluation and assessment by pathologists. The most widely and commonly used dyes in histopathology are hematoxylin and eosin (H&E) as most malignancies diagnosis is largely based on this protocol. H&E staining has been used for more than a century to identify tissue characteristics and structures morphologies that are needed for tumor diagnosis. In many cases, as tissue is scarce in clinical studies, fluorescence imaging is necessary to allow staining of the same specimen with multiple biomarkers simultaneously. Since fluorescence imaging is a relatively new technology in the pathology landscape, histopathologists are not used to or trained in annotating or interpreting these images. Aims, Settings and Design: To allow pathologists to annotate these images without the need for additional training, we designed an algorithm for the conversion of fluorescence images to brightfield H&E images. Subjects and Methods: In this algorithm, we use fluorescent nuclei staining to reproduce the hematoxylin information and natural tissue autofluorescence to reproduce the eosin information avoiding the necessity to specifically stain the proteins or intracellular structures with an additional fluorescence stain. Statistical Analysis Used: Our method is based on optimizing a transform function from fluorescence to H&E images using least mean square optimization. Results: It results in high quality virtual H&E digital images that can easily and efficiently be analyzed by pathologists. We validated our results with pathologists by making them annotate tumor in real and virtual H&E whole slide images and we obtained promising results. Conclusions: Hence, we provide a solution that enables pathologists to assess tissue and annotate specific structures based on multiplexed fluorescence images. PMID:29531846

Becoming an International Scientist in South Korea: Ho Wang Lee's Research Activity about Epidemic Hemorrhagic Fever.

PubMed

Shin, Miyoung

2017-04-01

In the 1960-70s, South Korea was still in the position of a science latecomer. Although the scientific research environment in South Korea at that time was insufficient, there was a scientist who achieved outcomes that could be recognized internationally while acting in South Korea. He was Ho Wang Lee(1928~ ) who found Hantann Virus that causes epidemic hemorrhagic fever for the first time in the world. It became a clue to identify causative viruses of hemorrhagic diseases that were scattered here and there throughout the world. In addition, these outcomes put Ho Wang Lee on the global center of research into epidemic hemorrhagic fever. This paper examines how a Korean scientist who was in the periphery of virology could go into the central area of virology. Also this article shows the process through which the virus found by Ho Wang Lee was registered with the international academia and he proceeded with follow-up research based on this progress to reach the level at which he generalized epidemic hemorrhagic fever related studies throughout the world. While he was conducting the studies, experimental methods that he had never experienced encountered him as new difficulties. He tried to solve the new difficulties faced in his changed status through devices of cooperation and connection. Ho Wang Lee's growth as a researcher can be seen as well as a view of a researcher that grew from a regional level to an international level and could advance from the area of non-mainstream into the mainstream. This analytic tool is meaningful in that it can be another method of examining the growth process of scientists in South Korea or developing countries.

Assessing the brain through the eye: New ways to explore hepatic encephalopathy.

PubMed

Arias, Natalia; Méndez, Marta; Alcalde, Ignacio; Íñigo-Portugués, Almudena; Merayo-Lloves, Jesús; Arias, Jaime; Arias, Jorge L

2017-05-01

Minimal hepatic encephalopathy (mHE) has been shown to affect daily functioning, quality of life, driving and overall mortality. However, little is known about treating or diagnosing early impairments in mHE. We studied one of its precipitating factors, portal hypertension which is driving the inflammatory process behind mHE. The purpose was to describe an indirect diagnostic method able to detect the pathology at early stages based on the study of the vascularization and mast cells conjunctival hyperplasia as secondary inflammatory response associated to portal hypertension. Finally, we correlated the presence of histological changes in the eye in mHE with deficits in behavioral task acquisition. Rats were trained on a stimulus-response task and a spatial working memory task using the Morris water maze. Two groups of animals were used: a SHAM (sham-operated) group (n=10) and a portal hypertension (HT) group (n=10). The triple portal vein ligation method was used to create an animal model of mHE. Latencies to reach the platform, number of glial fibrillary acidic protein-immunoreactive astrocytes (GFAP-IR), mast cell expression and presence/absence of blood and lymphatic vessels were examined. There were differences in stimulus-response behavioral performance, with a deficit in the acquisition in the HT group. However, no differences between groups were found on the spatial working memory task. At the same time, differences between groups were found in the GFAP-IR density, which was lower in the HT group, and in the number of mast cells and the presence of vessels, which were higher in the HT group. In this study, we provide the first preliminary insight into the validity of exploring the eye as a possible tool to assess the diagnosis of mHE conditions. Copyright © 2017 Elsevier Inc. All rights reserved.

Inverted Apatite (U-Th)/He and Fission-track Dates from the Rae craton, Baffin Island, Canada and Implications for Apatite Radiation Damage-He Diffusivity Models

NASA Astrophysics Data System (ADS)

Ault, A. K.; Reiners, P. W.; Thomson, S. N.; Miller, G. H.

2015-12-01

Coupled apatite (U-Th)/He and fission-track (AFT) thermochronology data from the same sample can be used to decipher complex low temperature thermal histories and evaluate compatibility between these two methods. Existing apatite He damage-diffusivity models parameterize radiation damage annealing as fission-track annealing and yield inverted apatite He and AFT dates for samples with prolonged residence in the He partial retention zone. Apatite chemistry also impacts radiation damage and fission-track annealing, temperature sensitivity, and dates in both systems. We present inverted apatite He and AFT dates from the Rae craton, Baffin Island, Canada, that cannot be explained by apatite chemistry or existing damage-diffusivity and fission track models. Apatite He dates from 34 individual analyses from 6 samples range from 237 ± 44 Ma to 511 ± 25 Ma and collectively define a positive date-eU relationship. AFT dates from these same samples are 238 ± 15 Ma to 350 ± 20 Ma. These dates and associated track length data are inversely correlated and define the left segment of a boomerang diagram. Three of the six samples with 20-90 ppm eU apatite grains yield apatite He and AFT dates inverted by 300 million years. These samples have average apatite Cl chemistry of ≤0.02 wt.%, with no correlation between Cl content and Dpar. Thermal history simulations using geologic constraints, an apatite He radiation damage accumulation and annealing model, apatite He dates with the range of eU values, and AFT date and track length data, do not yield any viable time-temperature paths. Apatite He and AFT data modeled separately predict thermal histories with Paleozoic-Mesozoic peaks reheating temperatures differing by ≥15 °C. By modifying the parameter controlling damage annealing (Rmr0) from the canonical 0.83 to 0.5-0.6, forward models reproduce the apatite He date-eU correlation and AFT dates with a common thermal history. Results imply apatite radiation damage anneals at higher temperatures than fission-track damage and the impact on coupled apatite He and AFT dates is magnified for protracted cooling histories. Further experimental and field-based tests are important for refining radiation damage and fission-track annealing parameters for accurate interpretation of apatite He- and AFT-derived thermal histories.

Factors influencing the contribution of staff to health education in schools.

PubMed

Jourdan, Didier; Mannix McNamara, Patricia; Simar, Carine; Geary, Tom; Pommier, Jeanine

2010-08-01

Understanding the contribution of the whole-school staff to health education (HE) is an important goal in HE research. This study aimed to identify the views of staff (principals; teachers; school nurses and doctors; counsellors and administrative, maintenance, canteen and cleaning staff) regarding the nature of their contribution to HE. The research is based on 207 semi-structured interviews of staff in a sample of five French middle schools (grade 6-9). Content analysis was performed using Bardin's method. The results showed that staff members have different views of their role, three main roles were identified: (i) as an educator in everyday life issues (72%); (ii) individual support, listening (14%) and (iii) taking part in collective projects and facilitation (14%). Professional status has a significant influence on the view they have of their contribution to HE. These results show that in order to facilitate consistent implementation of HE, schools need to be supported to build HE policy (need analysis, definition of priorities and partnerships) and also to develop the means by which an inclusive and real sharing of common culture among all staff can happen; this is not limited to teaching staff but includes non-teaching staff also.

Spin-density functional theory treatment of He+-He collisions

NASA Astrophysics Data System (ADS)

Baxter, Matthew; Kirchner, Tom; Engel, Eberhard

2016-09-01

The He+-He collision system presents an interesting challenge to theory. On one hand, a full treatment of the three-electron dynamics constitutes a massive computational problem that has not been attempted yet; on the other hand, simplified independent-particle-model based descriptions may only provide partial information on either the transitions of the initial target electrons or on the transitions of the projectile electron, depending on the choice of atomic model potentials. We address the He+-He system within the spin-density functional theory framework on the exchange-only level. The Krieger-Li-Iafrate (KLI) approximation is used to calculate the exchange potentials for the spin-up and spin-down electrons, which ensures the correct asymptotic behavior of the effective (Kohn-Sham) potential consisting of exchange, Hartree and nuclear Coulomb potentials. The orbitals are propagated with the two-center basis generator method. In each time step, simplified versions of them are fed into the KLI equations to calculate the Kohn-Sham potential, which, in turn, is used to generate the orbitals in the next time step. First results for the transitions of all electrons and the resulting charge-changing total cross sections will be presented at the conference. Work supported by NSERC, Canada.

The reducibility of heLa cell viability by Sargassum polycystum extracts

NASA Astrophysics Data System (ADS)

Firdaus, M.; Setijawati, D.; Islam, I.; Nursyam, H.; Kartikaningsih, H.; Yufidasari, H. S.; Prihanto, A. A.; Nurdiani, R.; Jaziri, A. A.

2018-04-01

Cervical cancer is the second largest cause of death-related cancer in women. The efficacy of cancer drugs is still low. Bioactive of brown seaweed has been studied by in vitro and in vivo as anticancer. The aim of this study was to evaluate the cytotoxicity of Sargassum polycystum extracts on HeLa cell, to recognize bioactive on extract and estimate the interaction between the bioactive and target protein. S. polycystum was found from Talango Island waters and HeLa cell was obtained from Indonesian Science Institute. Sample was extracted by ethanol, ethyl acetate and hexane, concentrated and finally, extracts were assayed on HeLa cell. The viability of this cell was quantified on ELISA-Reader. The bioactive compounds of the extract were elucidated by GC-MS. The interaction between bioactive and target protein was evaluated by using in silico method. The result showed that the lowest viability of HeLa cell on n-hexane extracts treatment. The n-hexane extract of this seaweed contained benzenepropanoic acid. This compound reduced HeLa cell viability by reducing of thrombin concentration. In conclusion, the benzene propanoic acid of S. polycystum was the cytotoxic agent and it is potential agent for anti-cervical cancer.

[The contribution of Augusto Orrego Luco to Chilean psychiatry].

PubMed

Ruiz Torres, A

1996-01-01

Augusto Orrego Luco born in 1848 and dead in 1933 in Valparaiso, was one of the greatest clinicians and researchers of chilean medicine during the late nineteenth and early twentieth century. Besides being a psychiatrist he contributed to literature, history, politics and medicine. He received his medical degree in 1874 and, apart from being an anatomist, soon became interested in mental illnesses. The title of his thesis was "Mental Hallucinations". He worked in the insane asylum after José Ramón Elguero. Later, in 1891, he was the successor of professor Carlos Sazie at the Hospital for Nervous and Mental Illnesses. Orrego Luco was influenced by french neurology of Jean Martin Charcot and taught a preferentially neurological psychiatry, based on the anatomo-clinical method. His original works were on traumatic hysteria, the mechanism of hypnosis, hysterical hemiplegia, causes of mental hallucinations, syphilitic etiology of Tabes and anatomy of cerebral sulci. In his work about mimical neuroses, he considered and obligation not to discriminate between organic and non-organic patients, because both suffer, he claimed. Presently, Orrego Luco is considered the creator and instigator of the Psychiatry chair, turning it into one of the main medical specialties in Chile.

[Mór Károlyi was born 150 years ago].

PubMed

Labádi, Lajos

2015-01-01

Dr. Mór Károlyi was born in Szentes (County Csongrád, South-East Hungary) in 1865 in a Jewish family. His original name was Móric Czukkermann--the name was changed to Mór Károlyi in 1883. Károlyi got his medical degree in 1889 at the Budapest Medical University. During his studies he was the student of József Arkövy, the founder of the Hungarian scientific dentistry. Károlyi later practised in Vienna from 1893 up to 1938. His main lines were the etiology of the diseases of the parodontal area and prosthetics. Thanks to his special method of treating traumatic parodontal diseases he made an international reputation. In 1932 he won the membership of the International Academy of Odontology (Buenos Aires). One of his etiological discoveries is still called Károlyi-effect in international terminology. After the so called Anschluss, Károlyi had to escape from Vienna. In 1938 he settled back to his native city, Szentes. In 1944, being a Jew he was first internated, then deported to Theresienstadt. He died a few days after the liberation of the camp, 17th May 1945.

[Al-Biruni--a universal scientist].

PubMed

Kujundzić, E; Masić, I

1999-01-01

Al-Biruni's was of Persian descent. He was born in Horesmiya and had studied mathematics, history and medicine. Acquiring knowledge from these sciences, he wrote an outstanding work on chronology of several nations and devoted it to Ziyarit ruler Kabus. He made a chronological overview of calendars from many nations, including Persians, Greeks, Egyptians, Jews, Melkitian and Nestorian Christians, Sabeyaans as well as the old Arabs. Data presented in the work, according to the later authors, were taken from very reliable sources. He was contemporary of Ibn-Sina, and thanks to their friendship, they have discussed very much miscellaneous topics. He belonged to the group of scholars, taken by Gaznevian Soultan Mahmud to a long journey to India. Afterwards Al-Biruni wrote and published detailed work "Description of India"--a work on cultural history of India. Due to excellent abilities of Al-Biruni as a philosopher and scholar, there are still significant and reliable notes about buddhistic philosophy, structure of castes and Brahmans' life style. In this Al-Biruni's masterpiece, there are many comparative analysis of Suffism and certain Indian philosophical methods. Al-Biruni's most important work is "Pharmacopoeia"--"Kitab al-saydala", which brilliantly describes all medicaments. This work has been published in many languages. He also wrote few works on astronomy and astrology. In those works he has explained some astrological events through scientific approach in a such peculiar way that nobody has ever explained before. He was also interested in sciences like geology, mineralology, geography, mathematics, psychology and many others.

Spectral broadening of characteristic γ-ray emission peaks from 12C(3He,pγ)14N reactions in fusion plasmas.

PubMed

Tardocchi, M; Nocente, M; Proverbio, I; Kiptily, V G; Blanchard, P; Conroy, S; Fontanesi, M; Grosso, G; Kneupner, K; Lerche, E; Murari, A; Cippo, E Perelli; Pietropaolo, A; Syme, B; Van Eester, D; Gorini, G

2011-11-11

The spectral broadening of characteristic γ-ray emission peaks from the reaction (12)C((3)He,pγ)(14)N was measured in D((3)He) plasmas of the JET tokamak with ion cyclotron resonance heating tuned to the fundamental harmonic of (3)He. Intensities and detailed spectral shapes of γ-ray emission peaks were successfully reproduced using a physics model combining the kinetics of the reacting ions with a detailed description of the nuclear reaction differential cross sections for populating the L1-L8 (14)N excitation levels yielding the observed γ-ray emission. The results provide a paradigm, which leverages knowledge from areas of physics outside traditional plasma physics, for the development of nuclear radiation based methods for understanding and controlling fusion burning plasmas.

The place of James Arnott (1797-1883) in the development of local anaesthesia in dentistry.

PubMed

Silver, K; Silver, J

2016-03-11

Dental disease in the form of caries and abscesses has been known since antiquity. Before the advent of anaesthesia, operations upon the mouth were painful. The introduction of general anaesthesia in the form of ether and chloroform seemed to provide a solution, but there was an unacceptable level of mortality. James Arnott introduced local anaesthesia by means of freezing with ice, which he considered safer. He waged a long campaign and his method received recognition and was used in France and the USA. His method stimulated the development of pharmacological anaesthesia.

Continuum Level Density of a Coupled-Channel System in the Complex Scaling Method

NASA Astrophysics Data System (ADS)

Suzuki, R.; Kruppa, A. T.; Giraud, B. G.; Katō, K.

2008-06-01

We study the continuum level density (CLD) in the formalism of the complex scaling method (CSM) for coupled-channel systems. We apply the formalism to the ^{4}He = [^{3}H + p] + [^3{He} + n] coupled-channel cluster model where there are resonances at low energy. Numerical calculations of the CLD in the CSM with a finite number of L^{2} basis functions are consistent with the exact result calculated from the S-matrix by solving coupled-channel equations. We also study channel densities. In this framework, the extended completeness relation (ECR) plays an important role.

TEMPERATURE SCENARIO DEVELOPMENT USING REGRESSION METHODS

EPA Science Inventory

A method of developing scenarios of future temperature conditions resulting from climatic change is presented. he method is straightforward and can be used to provide information about daily temperature variations and diurnal ranges, monthly average high, and low temperatures, an...

[Professor Feng Run-Shen's essential experience in penetration needling method].

PubMed

Feng, Mu-Lan

2009-04-01

Professor Feng Run-Shen is engaged in medicine for more than 60 years. He pays attention to medical ethics and has perfect medical skill. He energetically advocates combination of acupuncture with medication and stresses the concept of viewing the situation as a whole in selection of acupoints and treatment, particularly, clinical application of point properties. Clinically, he is accomplished in penetration needling, for which one needle acts on two or more points, enlarging the range of needling sensation, so it has very good therapeutic effects on many diseases. In the paper, the case samples about penetration needling in his clinical practice are summarized and introduced.

[Didactic strategies of Giovan Battista da Monte (1489-1551) for the reformation of medical studies at the Paduan Studium].

PubMed

Carrara, Daniela Mugnai

2004-01-01

Da Monte was a very important member of medical Humanism; his position within the medical cultural scene of his time was characterised by strong interests in the epistemological problems of medicine. He considered the whole medicine - not only theory - a practical science according to the Aristotelian concept of science. During his teaching years at the Paduan Studium he tried to overcome the division of medicine into medical theory and medical practice and he elaborated an unitary method of teaching, trying to follow the Galen's Methodus medendi, in order to give a true scientific foundation also to the medical practice.

V.A.Robsman: Nonlinear Testing and Building Industry

NASA Astrophysics Data System (ADS)

Rudenko, Oleg V.

2006-05-01

This talk is devoted to the memory of outstanding scientist and engineer Vadim A. Robsman who died in January 2005. Dr.Robsman was the Honored Builder of Russia. He developed and applied new methods of nondestructive testing of buildings, bridges, power plants and other building units. At the same time, he published works on fundamental problems of acoustics and nonlinear dynamics. In particular, he suggested a new equation of the 4-th order continuing the series of basic equations of nonlinear wave theory (Burgers Eq.: 2-nd order, Korteveg - de Vries Eq.: 3-rd order) and found exact solutions for high-intensity waves in scattering media.

Differentiating among penal states.

PubMed

Lacey, Nicola

2010-12-01

This review article assesses Loïc Wacquant's contribution to debates on penality, focusing on his most recent book, Punishing the Poor: The Neoliberal Government of Social Insecurity (Wacquant 2009), while setting its argument in the context of his earlier Prisons of Poverty (1999). In particular, it draws on both historical and comparative methods to question whether Wacquant's conception of 'the penal state' is adequately differentiated for the purposes of building the explanatory account he proposes; about whether 'neo-liberalism' has, materially, the global influence which he ascribes to it; and about whether, therefore, the process of penal Americanization which he asserts in his recent writings is credible.

Science and Society Colloquium

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

None

Mr. Randi will give an update of his lecture to the American Physical Society on the occasion of his award of the 1989 Forum Prize. The citation said: "for his unique defense of Science and the scientific method in many disciplines, including physics, against pseudoscience, frauds and charlatans. His use of scientific techniques has contributed to refuting suspicious and fraudulent claims of paranormal results. He has contributed significantly to public understanding of important issues where science and society interact". He is a professional magician and author of many books. He worked with John Maddox, the Editor of Nature to investigatemore » the claims of "water with memory".« less

The dynamism of professional and business identities.

PubMed

Gillis, Martin R

2011-01-01

Dr. Martin Gillis, a practitioner in Nova Scotia, was worried about the intrusion of commercial values in dentistry. Rather than complain, he sought advanced training in medical education, focusing on methods for revealing the practical influences of the school and practice environments on value formation. Today he teaches part-time and serves as an oral health liaison for diabetes with the International Diabetes Federation, in addition to his practice. He shares his thoughts about the issues facing the profession being similar to those in play more than 100 years ago and how our character is shaped by the way we choose to respond to economic pressures.

Dialectic Strategy.

DTIC Science & Technology

1993-11-29

perspective that we will apply to strategic analysis. Kant . Immanuel - Kant was born in Konigsberg, East Prussia in 1724. He entered the city’s...angles. Clearly, such methods have great utility in strategy making today. Carl von Clausewitz -had studied Kantian philosophy, 23 was probably...philosopher. He studied theology and philosophy at the universities of Jena and LEipzig and then became a private tutor. Fichte admired the works of Kant and

Gould, Benjamin Apthorp (1824-96)

NASA Astrophysics Data System (ADS)

Murdin, P.

2000-11-01

Astronomer, born in Boston, MA, his early work in Germany was on the observation and motion of comets and asteroids. His greatest work was his mapping of the stars of the southern skies. He helped found the National Observatory in Cordoba, Argentina, and was its director as it compiled a catalog of stars using recently developed photometric methods. On returning to the USA, he spent his final yea...

The Second European Conference on Atomic and Molecular Physics.

DTIC Science & Technology

1985-05-22

method works particularly well for important potential for technological rare gases. But he pointed emphatically applications. Catalysis and photography ...the parent ions and the frag- combined with mass spectroscopy, is a men bce ireaing difiut very powerful tool for probing electron- Tes f ca ngbe...an oversimplified but pedagogically fibers), he also reviewed briefly the ipressive manner, the working princi- Orsay reports of having observed gain

Verification of the harmonization of human epididymis protein 4 assays.

PubMed

Ferraro, Simona; Borille, Simona; Carnevale, Assunta; Frusciante, Erika; Bassani, Niccolò; Panteghini, Mauro

2016-10-01

Serum human epididymis protein 4 (HE4) has gained relevance as an ovarian cancer (OC) biomarker and new automated methods have replaced the first released manual EIA by tracing results to it. We verified agreement and bias of automated methods vs. EIA as well as possible effects on patients' management. One hundred and fifteen serum samples were measured by Abbott Architect i2000, Fujirebio Lumipulse G1200, Roche Modular E170, and Fujirebio EIA. Passing-Bablok regression was used to compare automated assays to EIA and agreement between methods was estimated by Lin's concordance correlation coefficient (CCC). The bias vs. EIA was estimated and compared to specifications derived from HE4 biological variation. Median (25th-75th percentiles) HE4 concentrations (pmol/L) were 84.5 (60.1-148.8) for EIA, 82.7 (50.3-153.9) for Abbott, 89.1 (55.2-154.9) for Roche, and 112.2 (67.8-194.2) for Fujirebio. Estimated regressions and agreements (95% confidence interval) were: Abbott=1.01(0.98-1.03) EIA-4.8(-7.5/-2.6), CCC=0.99(0.99-1.00); Roche=0.91(0.89-0.93) EIA+5.7(4.2/8.0), CCC=0.98(0.98-0.99); Fujirebio=1.20(1.17-1.24) EIA+ 2.4(-0.6/4.9), CCC=0.97(0.96-0.98). The average bias vs. EIA resulted within the desirable goal for Abbott [-3.3% (-6.1/-0.5)] and Roche [-0.2% (-3.0/2.5)]. However, while for Abbott the bias was constant and acceptable along the measurement concentration range, Roche bias increased up to -28% for HE4 values >250 pmol/L. Lumipulse showed a markedly positive bias [25.3% (21.8/28.8)]. Abbott and Roche assays exhibited a good comparability in the range of HE4 values around the previously recommended 140 pmol/L cut-off. For patient monitoring, however, the assay used for determining serial HE4 must not be changed as results from different systems in lower and higher concentration ranges can markedly differ.

In situ detrital zircon (U-Th)/He thermochronology

NASA Astrophysics Data System (ADS)

Tripathy, A.; Monteleone, B. D.; van Soest, M. C.; Hodges, K.; Hourigan, J. K.

2010-12-01

Detrital studies of both sand and rock are relevant to many problems, ranging from the climate and tectonics feedback debate to the long-term record of orogenic evolution. When applying the conventional (U-Th)/He technique to such studies, two important issues arise. Often, only euhedral grains are permissible for analysis in order to make simple geometric corrections for α-recoil. In detrital samples, this is problematic because euhedral grains can be scarce due to mechanical abrasion during transport, and potentially introduce bias in favour of more proximally sourced grains. Second, inherent to detrital studies is the need to date many grains (>100) per sample to ensure a representative sampling of the sediment source region, thus making robust conventional detrital studies both expensive and time-consuming. UV laser microprobes can improve this by permitting careful targeting of the grain interior away from the α-ejection zone, rendering the α-recoil correction unnecessary, thus eliminating bias toward euhedral grains. In the Noble Gas, Geochemistry, and Geochronology Laboratory at ASU, apatite and zircon have been successfully dated using in situ methods. For this study, the conventional and in situ techniques are compared by dating zircons from a modern river sand that drains a small catchment in the Mesozoic-Cenozoic Ladakh Batholith in NW India. This sample has a simple provenance, which allows us to demonstrate the robustness of the in situ method. Moreover, different microbeam techniques will be explored to establish the most efficient approach to obtain accurate and precise U-Th concentrations using synrock, which is our powdered, homogenized, and reconstituted zircon-rock standard. Without this, such in situ U-Th data would be difficult to obtain. 117 zircons were dated using the conventional (U-Th)/He method, revealing dates ranging from 9.70±0.35 to 106.6±3.5 Ma (2σ) with the major mode at 26 Ma. For comparison, 44 grains were dated using the in situ method, utilizing SIMS to determine the U-Th concentrations. The major mode is the same as the conventional dataset, with only single outliers missing from the in situ dataset. The in situ method is described as follows: Zircons are polished and imaged using cathodoluminesence to guide laser spot placement. Then, each grain is ablated with a 193nm ArF Excimer laser using 20-35µm beam sizes and depths of 10-17µm. After purification, 4He is analyzed on a ThermoScientific Helix Split Flight Tube mass spectrometer. U-Th concentrations are measured on the polished mount using a Cameca IMS 6f by placing a 60µm diameter beam directly over the He laser pit to cover the surface area contributing to the measured He. In theory, using LA-ICP-MS to obtain U-Th concentrations could be a faster, cheaper, but possibly less precise, technique. However, using laser ablation would allow pit sizes that average the U-Th concentration over the volume of material available that contributes to the measured He, thus accounting for intracrystalline α-recoil effects. Preliminary data on slabs of Sri Lankan zircon suggest this could be a viable method, but will require further exploration and refinement.

Thermodynamic properties of superfluid helium-3 and measurements of the specific heat of helium-3 in confined geometries as a probe for effects of impurity scattering

NASA Astrophysics Data System (ADS)

Choi, Hyoungsoon

Since its emergence, the Ginzburg-Landau theory has had a tremendous success in describing thermodynamic properties of superconductivity. In the case of superfluid 3He, not all five fourth-order parameters in the theory are known. Only four combinations of the five parameters have been experimentally established and theoretical attempts to calculate the parameters have had limited success as well. We present in this thesis a method to identify the five parameters independent of one another through a close inspection of the experiments and the theoretical calculation of Sauls and Serene. In an attempt to extend our understanding of the thermodynamic properties of 3He, we have also measured the specific heat of superfluid 3He. The measurements were performed on 3He confined in a high porosity silica aerogel and they served as a probe for the effects of impurity scattering. 3He in aerogel clearly shows behavior different from that of pure 3He: including suppression of the transition temperature and the order parameter. We have also looked at 3He in silver sinter. The difference in structures between the silver sinter and the aerogel are manifested in differences in the specific heat. In both cases, however, the impurity scattering creates Andreev bound states and we present evidence for them with our measurements.

Obituary: Eugene Richard Tomer, 1932-2007

NASA Astrophysics Data System (ADS)

Dunkl, Charles F.

2009-01-01

Dr. Eugene R. Tomer passed away on 2 July 2007 at his home in San Francisco, California. The cause of death was cancer. Tomer was a consulting applied mathematician with a wide range of interests in dynamical astronomy, electromagnetic theory for use in communications, and computational methods of applied mathematics. He was a member of AAS, and the Society for Applied and Industrial Mathematics [SIAM]. With K. H. Prendergast, he co-wrote the influential paper "Self-consistent Models of Elliptical Galaxies," published in the Astronomical Journal 75 (1970), 674-679. This paper has been cited over eighty times. Tomer was born on 13 June 1932. He earned the Ph.D. in Mathematics at the University of California-Berkeley in 1978 (title of dissertation: On the C*-algebra of the Hermite Operator). In 1996 he and A. F. Peterson wrote "Meeting the Challenges Presented by Computational Electromagnetics," a publication of the Naval Postgraduate School at Monterey, California. This writer met Eugene at the 1992 Annual SIAM meeting in Los Angeles in connection with the Activity Group on Orthogonal Polynomials and Special Functions, which the writer chaired at the time. Eugene volunteered to edit the Newsletter of the group, which he did from July 1992 to July 1995. Thanks to his skills and efforts, the Newsletter became a carefully edited, professional publication. Eugene not only organized a Problems Column, attracting questions in pure and applied mathematics, but he also designed the logo for the group. He gave much time and effort to this service, in an era when copy had to be physically assembled and mailed to SIAM Headquarters. Eventually he felt he had done what he could for the Activity Group. He told me that he hoped the Group would get seriously involved with applications such as in astronomy, physics, and sciences that use special function solutions of differential equations. During Tomer's editorship, we communicated mostly by e-mail, our homes being far apart. He was a good friend to the Group and to me, as much as one can be over a separation of thousands of miles. As well, Eugene was an active amateur radio operator, much appreciated by his local amateur radio community, with call sign WI6X. He left behind family, friends, and one son.

Problems in radiation transfer in astrophysics: An escape probability treatment of line overlap and a model of masers around VX Sgr

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

Lockett, P.B.

1989-01-01

The escape probability formalism is used in this dissertation to treat two problems in astrophysical radiative transfer. The first problem concerns line overlap, which occurs when two or more spectral lines lie close enough together that there is a significant probability that a photon emitted in one of the lines can be absorbed in another. The second problem involves creating a detailed model of the masers around the supergiant star, VX Sgr. The author has developed an escape probability procedure that accounts for the effects of line overlap by integrating the amount of absorption in each of the overlapping lines.more » This method was used to test the accuracy of a simpler escape probability formalism developed by Elitzur and Netzer that utilized rectangular line profiles. Good agreement between the two methods was found for a wide range of physical conditions. The more accurate method was also used to examine the effects of line overlap of the far infrared lines of the OH molecule. This overlap did have important effects on the level populations and could cause maser emission. He has also developed a detailed model of the OH 1612 and water masers around VX Sgr. He found that the masers can be adequately explained using reasonable estimates for the physical parameters. He also was able to provide a tighter constraint on the highly uncertain mass loss rate from the star. He had less success modeling the SiO masers. His explanation will require a more exact method of treating the many levels involved and also a more accurate knowledge of the relevant physical input parameters.« less

Visual detection of telomerase activity with a tunable dynamic range by using a gold nanoparticle probe-based hybridization protection strategy

NASA Astrophysics Data System (ADS)

Wang, Jiasi; Wu, Li; Ren, Jinsong; Qu, Xiaogang

2014-01-01

We developed a novel telomere complementary (TC) oligonucleotide modified AuNP probe (TC-AuNPs) for colorimetric analysis of telomerase activity. The mechanism of this method is that the telomerase reaction products (TRP), which can hybridize with the TC-AuNPs, are able to protect the AuNPs from the aggregation induced by salt. It is demonstrated that the colorimetric method enabled the analysis of the telomerase activity in 1000 HeLa cells with the naked eye, and down to 100 HeLa cells with the aid of UV-Vis spectroscopy. This strategy is not only convenient and sensitive, but also has a tunable dynamic range. The platform is also applicable for the initial screening of a telomerase inhibitor to discover new anticancer drugs.We developed a novel telomere complementary (TC) oligonucleotide modified AuNP probe (TC-AuNPs) for colorimetric analysis of telomerase activity. The mechanism of this method is that the telomerase reaction products (TRP), which can hybridize with the TC-AuNPs, are able to protect the AuNPs from the aggregation induced by salt. It is demonstrated that the colorimetric method enabled the analysis of the telomerase activity in 1000 HeLa cells with the naked eye, and down to 100 HeLa cells with the aid of UV-Vis spectroscopy. This strategy is not only convenient and sensitive, but also has a tunable dynamic range. The platform is also applicable for the initial screening of a telomerase inhibitor to discover new anticancer drugs. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr05185d

An evolutionary algorithm for large traveling salesman problems.

PubMed

Tsai, Huai-Kuang; Yang, Jinn-Moon; Tsai, Yuan-Fang; Kao, Cheng-Yan

2004-08-01

This work proposes an evolutionary algorithm, called the heterogeneous selection evolutionary algorithm (HeSEA), for solving large traveling salesman problems (TSP). The strengths and limitations of numerous well-known genetic operators are first analyzed, along with local search methods for TSPs from their solution qualities and mechanisms for preserving and adding edges. Based on this analysis, a new approach, HeSEA is proposed which integrates edge assembly crossover (EAX) and Lin-Kernighan (LK) local search, through family competition and heterogeneous pairing selection. This study demonstrates experimentally that EAX and LK can compensate for each other's disadvantages. Family competition and heterogeneous pairing selections are used to maintain the diversity of the population, which is especially useful for evolutionary algorithms in solving large TSPs. The proposed method was evaluated on 16 well-known TSPs in which the numbers of cities range from 318 to 13509. Experimental results indicate that HeSEA performs well and is very competitive with other approaches. The proposed method can determine the optimum path when the number of cities is under 10,000 and the mean solution quality is within 0.0074% above the optimum for each test problem. These findings imply that the proposed method can find tours robustly with a fixed small population and a limited family competition length in reasonable time, when used to solve large TSPs.

An optimized full-configuration-interaction nuclear orbital approach to a ``hard-core'' interaction problem: Application to (3He)N-Cl2(B) clusters (N<=4)

NASA Astrophysics Data System (ADS)

de Lara-Castells, M. P.; Villarreal, P.; Delgado-Barrio, G.; Mitrushchenkov, A. O.

2009-11-01

An efficient full-configuration-interaction nuclear orbital treatment has been recently developed as a benchmark quantum-chemistry-like method to calculate ground and excited "solvent" energies and wave functions in small doped ΔEest clusters (N ≤4) [M. P. de Lara-Castells, G. Delgado-Barrio, P. Villarreal, and A. O. Mitrushchenkov, J. Chem. Phys. 125, 221101 (2006)]. Additional methodological and computational details of the implementation, which uses an iterative Jacobi-Davidson diagonalization algorithm to properly address the inherent "hard-core" He-He interaction problem, are described here. The convergence of total energies, average pair He-He interaction energies, and relevant one- and two-body properties upon increasing the angular part of the one-particle basis set (expanded in spherical harmonics) has been analyzed, considering Cl2 as the dopant and a semiempirical model (T-shaped) He-Cl2(B) potential. Converged results are used to analyze global energetic and structural aspects as well as the configuration makeup of the wave functions, associated with the ground and low-lying "solvent" excited states. Our study reveals that besides the fermionic nature of H3e atoms, key roles in determining total binding energies and wave-function structures are played by the strong repulsive core of the He-He potential as well as its very weak attractive region, the most stable arrangement somehow departing from the one of N He atoms equally spaced on equatorial "ring" around the dopant. The present results for N =4 fermions indicates the structural "pairing" of two H3e atoms at opposite sides on a broad "belt" around the dopant, executing a sort of asymmetric umbrella motion. This pairing is a compromise between maximizing the H3e-H3e and the He-dopant attractions, and suppressing at the same time the "hard-core" repulsion. Although the He-He attractive interaction is rather weak, its contribution to the total energy is found to scale as a power of three and it thus increasingly affects the pair density distributions as the cluster grows in size.

Memoriam for David G. Koch, 1945-2012

NASA Astrophysics Data System (ADS)

Borucki, William J.

2013-01-01

Dave worked on scientific space instrumentation since the Apollo era in the mid-1960s. He was born and raised in Milwaukee, WI, and attended Milwaukee Lutheran High School where he built a Michelson interferometer that proved to be a stepping-stone for his interest in physics. Dave graduated from the University of Wisconsin-Madison, where he earned a Bachelor of Science in applied mathematics and engineering physics in 1967. As an undergraduate, he worked on balloon-launched sounding rockets and scientific instruments in X-ray and gamma-ray astronomy. At Cornell University, Dave earned a master's degree in 1971, and a doctorate in 1972, both in physics. He built a balloon-borne gamma-ray telescope that detected the first pulsed high-energy gamma rays from the Crab pulsar. In 1972, Dave began his career at American Science and Engineering where he was the project scientist for the Uhuru X-ray satellite. Later, he served as the project scientist for the development of the Einstein Observatory. Dave joined the Smithsonian Center for Astrophysics in 1977 as the project scientist for the Spacelab-2 infrared telescope. There, he served as a co-investigator on the Space Infrared Telescope Facility - IRAC camera proposal, and co-investigator on the Submillimeter Wave Astronomy Satellite, which launched in December 1998. Dave came to NASA Ames Research Center to lead the mission operations for SIRTF and SOFIA (Stratospheric Observatory for Infrared Astronomy) in 1988. He created the Flight Opportunities for Science Teacher EnRichment project. In 1992, Dave began working on what has become the Kepler mission, for which he served as deputy principal investigator until retiring in August 2011. Dave's contributions were many but most notably, he led the development of the Kepler Technology Demonstration used to prove that the transit photometry method would work under on-orbit conditions. Dave loved to build things and was passionate about engaging young hearts and minds with the excitement of science and space exploration. He was particularly fond of educating and empowering teachers with the right tools to connect with the formal and informal classroom.

Helium Diffusion in Olivine

NASA Astrophysics Data System (ADS)

Cherniak, D. J.; Watson, E. B.

2011-12-01

Diffusion of helium has been characterized in natural Fe-bearing olivine (~Fo90) and synthetic forsterite. Polished, oriented slabs of olivine were implanted with 3He, at 100 keV at a dose of 5x1015/cm2 or at 3.0 MeV at a dose of 1x1016/cm2. A set of experiments on the implanted olivine were run in 1-atm furnaces. In addition to the one-atm experiments, experiments on implanted samples were also run at higher pressures (2.6 and 2.7 GPa) to assess the potential effects of pressure on He diffusion and the applicability of the measured diffusivities in describing He transport in the mantle. The high-pressure experiments were conducted in a piston-cylinder apparatus using an "ultra-soft" pressure cell, with the diffusion sample directly surrounded by AgCl. 3He distributions following experiments were measured with Nuclear Reaction Analysis using the reaction 3He(d,p)4He. This direct profiling method permits us to evaluate anisotropy of diffusion, which cannot be easily assessed using bulk-release methods. For diffusion in forsterite parallel to c we obtain the following Arrhenius relation over the temperatures 250-950°C: D = 3.91x10-6exp(-159 ± 4 kJ mol-1/RT) m2/sec. The data define a single Arrhenius line spanning more than 7 orders of magnitude in D and 700°C in temperature. Diffusion parallel to a appears slightly slower, yielding an activation energy for diffusion of 135 kJ/mol and a pre-exponential factor of 3.73x10-8 m2/sec. Diffusion parallel to b is slower than diffusion parallel to a (by about two-thirds of a log unit); for this orientation an activation energy of 138 kJ/mol and a pre-exponential factor of 1.34x10-8 m2/sec are obtained. This anisotropy is broadly consistent with observations for diffusion of Ni and Fe-Mg in olivine. Diffusion in Fe-bearing olivine (transport parallel to b) agrees within uncertainty with findings for He diffusion in forsterite. The higher-pressure experiments yield diffusivities in agreement with those from the 1-atm experiments, indicating that the results reported here can be reasonably applied to modeling He transport in the upper mantle. The insensitivity of He diffusion to pressure over the investigated range of conditions suggests that compression of the mineral lattice is not sufficient to significantly influence migration of the relatively small helium atoms, which likely diffuse via crystal interstices. The He diffusivities in this work are generally consistent with results from the study of Futagami et al. (1993), who measured He diffusion in natural olivine by outgassing 4He implanted samples, and with the diffusivities measured by bulk-release of 4He and 3He by Shuster et al. (2003), but are about 2 orders of magnitude slower than the recent findings of Tolstikhin et al. (2010) and Blard et al. (2008) . An up-temperature extrapolation of our data also show reasonable agreement with the higher-temperature measurements of Hart (1984). Blard et al. (2008) GCA 72, 3788-3803; Futagami et al. (1993) GCA 57, 3177-3194; Hart (1984) EPSL 70, 297-302; Shuster et al.( 2003) EPSL 217, 19-32; Tolstikhin et al. (2010) GCA 74, 1436-1447

Ab initio study of the Jπ=0± continuum structures in 4He

NASA Astrophysics Data System (ADS)

Aoyama, S.; Baye, D.

2018-05-01

The Jπ=0± continuum structures in 4He are investigated by using an ab initio reaction theory with the microscopic R -matrix method. In the Ex≥˜20 MeV excitation energy region of 4He, the continuum states are mainly described by the t +p , h +n , and d +d channels. The Jπ=0± elastic phase shifts of the t +p and h +n channels show an apparently resonant behavior which might indicate the existence of excited 03+ and 02- resonance states of 4He above the known 02+ and 01- ones. However, the corresponding 03+ and 02- resonances have not been observed yet, although an experimental candidate with a large decay width is reported for 02-. In this paper, by analyzing the Jπ=0± S matrices, we discuss why the observation of these states is unlikely.

Influence of abuse on condom negotiation among Mexican-American women involved in abusive relationships.

PubMed

Davila, Yolanda R

2002-01-01

This study explored cultural and gender perspectives of abuse on condom negotiation behaviors for AIDS prevention among Mexican-American women in abusive intimate relationships. A convenience sample of 20 abused women participated in the study. Data were collected through a demographic questionnaire and audiotaped responses to a semistructured interview guide. Content analysis using QSR NUDIST was used to analyze the verbatim transcriptions of all participant interviews. The predominant category, "He always got his way," was developed in response to the content of the verbatim transcriptions. The category was further expanded to include the self-descriptive subcategories of "He beat me," "He made me feel bad," and "He forced me." Through content analysis, a relationship between abuse by male sexual partners and condom negotiation for AIDS prevention was identified. Trustworthiness of the data collection and analysis was established through methods suggested by Lincoln and Guba.

Analysis of the financial factors governing the profitability of lunar helium-3

NASA Technical Reports Server (NTRS)

Kulcinski, G. L.; Thompson, H.; Ott, S.

1989-01-01

Financial factors influencing the profitability of the mining and utilization of lunar helium-3 are examined. The analysis addressed the following questions: (1) which financial factors have the greatest leverage on the profitability of He-3; (2) over what range can these factors be varied to keep the He-3 option profitable; and (3) what ultimate effect could this energy source have on the price of electricity for U.S. consumers. Two complementary methods of analysis were used in the assessment: rate of return on incremental investment required and reduction revenue requirements (total cost to customers) achieved. Some of the factors addressed include energy demand, power generation costs with and without fusion, profitability for D-He(3) fusion, annual capital and operating costs, launch mass and costs, He-3 price, and government funding. Specific conclusions are made with respect to each of the companies considered: utilities, lunar mining company, and integrated energy company.

Phase Diagram of Hydrogen and a Hydrogen-Helium Mixture at Planetary Conditions by Quantum Monte Carlo Simulations

NASA Astrophysics Data System (ADS)

Mazzola, Guglielmo; Helled, Ravit; Sorella, Sandro

2018-01-01

Understanding planetary interiors is directly linked to our ability of simulating exotic quantum mechanical systems such as hydrogen (H) and hydrogen-helium (H-He) mixtures at high pressures and temperatures. Equation of state (EOS) tables based on density functional theory are commonly used by planetary scientists, although this method allows only for a qualitative description of the phase diagram. Here we report quantum Monte Carlo (QMC) molecular dynamics simulations of pure H and H-He mixture. We calculate the first QMC EOS at 6000 K for a H-He mixture of a protosolar composition, and show the crucial influence of He on the H metallization pressure. Our results can be used to calibrate other EOS calculations and are very timely given the accurate determination of Jupiter's gravitational field from the NASA Juno mission and the effort to determine its structure.

Determination of detonation parameters for liquid High Explosives

NASA Astrophysics Data System (ADS)

Mochalova, Valentina; Utkin, Alexander

2011-06-01

The experimental investigation of detonation parameters and reaction zone structure in liquid HE (bis-(2-fluoro-2,2-dinitroethyl)formal (FEFO), tetranitromethane (TNM), nitromethane (NM)) was conducted. Detonation front in TNM and NM was stable while the instability of detonation in FEFO was observed. Von Neumann spike was recorded for these HE and its parameters were determined. The different methods for C-J point determination were used for each HE. For FEFO reaction time τ was found from experiments with different charge diameters (τ is approximately equal to 300 ns); for TNM - at fixed diameter and different lengths of charges (τ ~ 200 ns); for NM - at fixed diameter and length of charges, but detonation initiation was carried out by different explosive charges (τ ~ 50 ns). It was found that in TNM the detonation velocity depends on charge diameter. Maximum value of reaction rate in investigated liquid HE was observed after shock jump and induction time was not recorded.

Determination of detonation parameters for liquid high explosives

NASA Astrophysics Data System (ADS)

Mochalova, Valentina; Utkin, Alexander

2012-03-01

The experimental investigation of detonation parameters and reaction zone structure in liquid HE (bis-(2-fluoro-2,2-dinitroethyl)formal (FEFO), tetranitromethane (TNM), nitromethane (NM)) was conducted by means of laser interferometer VISAR. Detonation front in TNM and NM was stable while the instability of detonation in FEFO was observed. The parameters of Von Neumann spike were determined for these HE. The different methods for C-J point determination were used for each HE. For FEFO reaction time t was found from experiments with different charge diameters (τ is approximately equal to 300 ns); for TNM - at fixed diameter and different lengths of charges (τ ≈ 200 ns); for NM - at fixed diameter and length of charges, but detonation initiation was carried out by different explosive charges (τ ≈ 50 ns). It was found that in TNM the detonation velocity depends on charge diameter. Maximum value of reaction rate in investigated liquid HE was observed after shock jump.

Effects of combustibles on internal quasi-static loads

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

Sandoval, N.R.; Hokanson, J.C.; Esparza, E.D.

1984-08-01

The phenomenon of quasi-static pressure enhancement produced when combustible materials are placed near HE sources has been recently discovered. The effects of placing solid and liquid combustible materials near detonating explosives on internal blast loading was measured during tests conducted in a one-eighth scale model of a containment structure. In many cases, dramatic increases in gas pressures resulted. Principal conclusions of this study are: combustible materials near explosives can markedly increase gas pressures in enclosed structures; there is a lack of data on HE-combustible combinations; quasi-static loading calculations should include estimates of contributions from the burning of combustible materials whenevermore » such materials are expected to be in intimate contact with HE sources; and effects of combustibles should be investigated further to determine methods for prediction. Variations in charge to combustible mass, charge type, structure volume, degree of venting and degree of contact between HE and combustible sbould be studied.« less

The work of Galileo and conformation of the experiment in physics

NASA Astrophysics Data System (ADS)

Alvarez, J. L.; Posadas, Y.

2003-02-01

It is very frequent to find comments and references to Galileo's work suggesting that he based his affirmations on a logic thought and not on observations. In this paper we present an analysis of some experiments that he realized and were unknown in the XVI and XVII centuries; in they we find a clear description of the methodology that Galileo follows in order to reach the results that he presents in his formal work, particularly in Discorsi. In contrast with the Aristotelian philosophy, in these manuscripts Galileo adopt a methodology with which he obtain great contributions for the modem conformation of the experimental method, founding so a methodology for the study of the movement. We use this analysis as an example of the difficulties that are present in the conformation of the modem experimentation and we point out the necessity to stress the importance of the scientific methodology in the teaching of physics.

Matter and charge distributions of 6He and 5,6,7,9Li within the dynamic-correlation model

NASA Astrophysics Data System (ADS)

Tomaselli, M.; Hjorth-Jensen, M.; Fritzsche, S.; Egelhof, P.; Neumaier, S. R.; Mutterer, M.; Kühl, T.; Dax, A.; Wang, H.

2000-12-01

The matter and the charge distributions of the 6He and 5,6,7,9Li isotopes are investigated within the dynamic-correlation model (DCM) which describes the ground states of light nuclei in terms of microscopic correlated clusters: the valence particles and the intrinsic vacuum states. The amplitudes of these mixed-mode wave functions are calculated in the framework of nonperturbative solutions of the equation of motion method (EOMM). The matter and charge mean square radii are in good agreement with experimental results. The calculated matter distribution of the 6He nucleus is characterized by a halo structure less pronounced than that calculated by the three cluster models. The charge distribution of 6Li reproduces well the electron scattering data. Good agreement with experimental data has been also achieved for the proton scattering cross sections of p-6He at an energy of 0.7 GeV/nucleon.

The case of Anders Behring Breivik - language of a lone terrorist.

PubMed

Leonard, Cecilia H; Annas, George D; Knoll, James L; Tørrissen, Terje

2014-01-01

Anders Behring Breivik carried out a massacre in Norway on July 22, 2011, killing a total 77 persons and leaving 42 others severely wounded. He detonated a bomb in Oslo and then drove to the island of Utøya, where he shot and killed youngsters gathered at a youth camp. The authors performed an analysis of Breivik's writing style in his extensive manifesto which he published hours before the attacks, and also referred to the two psychiatrists' reports. The first report concluded that he suffered from paranoid schizophrenia. The authors concurred with the second report. Breivik seemed to be a person with narcissistic personality disorder, whose grandiosity might have caused him to be regarded initially as mentally deranged; however, closer examination revealed his deliberate attempt to methodically indoctrinate and deceive potential readers, to alarm potential targets and to terrorize a nation. Copyright © 2014 John Wiley & Sons, Ltd.

[Jakob Klaesi on his 120th birthday].

PubMed

Haenel, T

2003-05-01

Jakob Klaesi was born on the 29th May 1883 in Glarus Canton (Switzerland) and was assistant and later head physician at the Psychiatric University Hospital in Zurich, directed by Eugen Bleuler. Klaesi directed the new Psychiatric Outpatient Department in Basel from 1923 to 1926 and later founded the Schloss Kronau private clinic in the Zurich Canton. In 1933 he became director of the Psychiatric University Hospital in Bern. His attitude toward somatic treatment methods was skeptical, although about 1920 he founded a psychiatric sleep cure with Somnifen. Klaesi was primarily a psychotherapist and interested in the psychodynamics of his patients. With his great empathy, he was able to understand especially well their expressive behaviour. This capacity for empathy and his philosophic orientation enabled him to develop a phenomenological analysis of expression. He died on the 17th August 1980. Differences and parallels to the thinking of Alfred Adler and Karl Jaspers are discussed.

Michael Sprague | NREL

Science.gov Websites

student, he developed a parallel spectral finite element method for treating the interaction of large mechanics of fluids, structures, and their interaction|Spectral finite-element methods for time-dependent

Primordial 4He abundance: a determination based on the largest sample of H II regions with a methodology tested on model H II regions

NASA Astrophysics Data System (ADS)

Izotov, Y. I.; Stasińska, G.; Guseva, N. G.

2013-10-01

We verified the validity of the empirical method to derive the 4He abundance used in our previous papers by applying it to CLOUDY (v13.01) models. Using newly published He i emissivities for which we present convenient fits as well as the output CLOUDY case B hydrogen and He i line intensities, we found that the empirical method is able to reproduce the input CLOUDY 4He abundance with an accuracy of better than 1%. The CLOUDY output data also allowed us to derive the non-recombination contribution to the intensities of the strongest Balmer hydrogen Hα, Hβ, Hγ, and Hδ emission lines and the ionisation correction factors for He. With these improvements we used our updated empirical method to derive the 4He abundances and to test corrections for several systematic effects in a sample of 1610 spectra of low-metallicity extragalactic H ii regions, the largest sample used so far. From this sample we extracted a subsample of 111 H ii regions with Hβ equivalent width EW(Hβ) ≥ 150 Å, with excitation parameter x = O2+/O ≥ 0.8, and with helium mass fraction Y derived with an accuracy better than 3%. With this subsample we derived the primordial 4He mass fraction Yp = 0.254 ± 0.003 from linear regression Y - O/H. The derived value of Yp is higher at the 68% confidence level (CL) than that predicted by the standard big bang nucleosynthesis (SBBN) model, possibly implying the existence of different types of neutrino species in addition to the three known types of active neutrinos. Using the most recently derived primordial abundances D/H = (2.60 ± 0.12) × 10-5 and Yp = 0.254 ± 0.003 and the χ2 technique, we found that the best agreement between abundances of these light elements is achieved in a cosmological model with baryon mass density Ωbh2 = 0.0234 ± 0.0019 (68% CL) and an effective number of the neutrino species Neff = 3.51 ± 0.35 (68% CL). Based on observations collected at the European Southern Observatory, Chile, programs 073.B-0283(A), 081.C-0113(A), 65.N-0642(A), 68.B-0310(A), 69.C-0203(A), 69.D-0174(A), 70.B-0717(A), 70.C-0008(A), 71.B-0055(A).Based on observations at the Kitt Peak National Observatory, National Optical Astronomical Observatory, operated by the Association of Universities for Research in Astronomy, Inc., under contract with the National Science Foundation.Tables 2 and 3 are available in electronic form at http://www.aanda.org

Fusion Ash Separation in the Princeton Field-Reversed Configuration Reactor

NASA Astrophysics Data System (ADS)

Abbate, Joseph; Yeh, Meagan; McGreivy, Nick; Cohen, Samuel

2016-10-01

The Princeton Field-Reversed Configuration (PFRC) concept relies on low-neutron production by D-3He fusion to enable small, safe nuclear-fusion reactors to be built, an approach requiring rapid and efficient extraction of fusion ash and energy produced by D-3He fusion reactions. The ash exhaust stream would contain energetic (0.1-1 MeV) protons, T, 3He, and 4He ions and nearly 1e5 cooler (ca. 100 eV) D ions. The T extracted from the reactor would be a valuable fusion product in that it decays into 3He, which could be used as fuel. If the T were not extracted it would be troublesome because of neutron production by the D-T reaction. This paper discusses methods to separate the various species in a PFRC reactor's exhaust stream. First, we discuss the use of curved magnetic fields to separate the energetic from the cool components. Then we discuss exploiting material properties, specifically reflection, sputtering threshold, and permeability, to allow separation of the hydrogen from the helium isotopes. DOE Contract Number DE-AC02-09CH11466.

Improvement in antiproliferative activity of Angelica gigas Nakai by solid dispersion formation via hot-melt extrusion and induction of cell cycle arrest and apoptosis in HeLa cells.

PubMed

Jiang, Yunyao; Piao, Jingpei; Cho, Hyun-Jong; Kang, Wie-Soo; Kim, Hye-Young

2015-01-01

Angelica gigas Nakai (AGN) is one of the most popular herbal medicines and widely used as a functional food product. In this study, AGN was firstly processed by a low-temperature turbo mill and a hot melting extruder to reduce particle size and form solid dispersion (SD). Anticancer activity against HeLa cells was then examined. AGN-SD based on Soluplus was formed via hot-melt extrusion (HME) and showed the strongest cytotoxic effect on HeLa cells. In addition, the possible mechanism of cell death induced by AGN-SD on HeLa cells was also investigated. AGN-SD decreased cell viability, induced apoptosis, increased the production of reactive oxygen species, regulated the expression of Bcl-2 and Bax, and induced G2/M phase arrest in HeLa cells. This study suggested that AGN-SD based on Soluplus and the method to improve antiproliferative effect by SD formation via HME may be suitable for application in the pharmaceutical industry.

Niels Stensen (1638-1686): scientist, neuroanatomist, and saint.

PubMed

Perrini, Paolo; Lanzino, Giuseppe; Parenti, Giuliano Francesco

2010-07-01

Niels Stensen (1638-1686) was a prominent Danish scientist who laid the foundations of paleontology, geology, and crystallography. He undertook a personal search for the truth, rejecting many assumptions of his time, and he struggled to acquire a firm foundation of knowledge based on close observation and rigorous experimentation. Niels Stensen is known eponymously for the discovery of the duct of the parotid gland (ductus stenonianus) but most clinicians are not familiar with his contributions to anatomy beyond his studies on the glands. In 1665, he delivered a lecture in Paris on the anatomy of the brain, the Discours sur l'anatomie du cerveau ("A Dissertation on the Anatomy of the Brain"), which is a seminal investigation on methods in neuroscience. His scientific letter on a hydrocephalic calf represents an early pathophysiological investigation on hydrocephalus. In 1667 Stensen converted to Catholicism and in 1677 he was consecrated titular bishop of Titiopolis. He spent the last years of his life in poverty and traveled continuously trying to bring back northern Europe to Catholicism. This essay highlights the life and the scientific contributions of Niels Stensen, with emphasis on his contributions to neuroscience.

HE4 as a biomarker for ovarian and endometrial cancer management

PubMed Central

Li, Jinping; Dowdy, Sean; Tipton, Tracy; Podratz, Karl; Lu, Wei-Guo; Xie, Xing; Jiang, Shi-Wen

2012-01-01

Ovarian and endometrial cancer will be diagnosed in over 63,000 women in 2009, resulting in 22,000 deaths in the USA. Histologic screening, such as pap smears for detection of cervical cancer, is not feasible for these diseases given difficulty with access to the tissue. Thus, a serum-screening test using a biomarker or panel of biomarkers would be useful to aid in cancer diagnosis, detection of recurrence and as a means to monitor response to therapy. In this review, we focus on the human epididymis protein (HE)4 gene, which appears to have potential as a biomarker for both of these diseases. The structure and methods of detection of HE4 are discussed. Preliminary data show that HE4 may have more potential than cancer antigen 125 in discriminating benign from cancerous ovarian masses, and has the strongest correlation with endometrial cancer of all markers tested to date. Utilizing risk stratification, a panel of biomarkers including HE4 may ultimately be useful for detecting ovarian and endometrial cancer at an early stage in patients at high risk. PMID:19732003

Excitations in the quantum liquid 4He: A review

NASA Astrophysics Data System (ADS)

Glyde, H. R.

2018-01-01

Progress made in measuring and interpreting the elementary excitations of superfluid and normal liquid {\\hspace{0pt}}^4He in the past 25 years is reviewed. The goal is to bring up to date the data, calculations and our understanding of the excitations since the books and reviews of the early 1990s. Only bulk liquid {\\hspace{0pt}}^4He is considered. Reference to liquid {\\hspace{0pt}}^3He , mixtures, reduced dimensions (films and confined helium) is made where useful to enhance interpretation. The focus is on the excitations as measured by inelastic neutron scattering methods. The review covers the dynamical response of liquid {\\hspace{0pt}}^4He from the collective excitations at low energy and long wavelength (i.e. phonon-roton modes) to the single particle excitations at high energy from which the atomic momentum distribution and Bose-Einstein condensate fraction are determined. A goal is to show the interplay of these excitations with other spectacular properties such as superfluidity and the test of fundamental calculations of quantum liquids that is possible. The role of Bose-Einstein condensation in determining the nature of the \

Intense beams from gases generated by a permanent magnet ECR ion source at PKU.

PubMed

Ren, H T; Peng, S X; Lu, P N; Yan, S; Zhou, Q F; Zhao, J; Yuan, Z X; Guo, Z Y; Chen, J E

2012-02-01

An electron cyclotron resonance (ECR) ion source is designed for the production of high-current ion beams of various gaseous elements. At the Peking University (PKU), the primary study is focused on developing suitable permanent magnet ECR ion sources (PMECRs) for separated function radio frequency quadrupole (SFRFQ) accelerator and for Peking University Neutron Imaging Facility. Recently, other kinds of high-intensity ion beams are required for new acceleration structure demonstration, simulation of fusion reactor material irradiation, aviation bearing modification, and other applications. So we expanded the ion beam category from O(+), H(+), and D(+) to N(+), Ar(+), and He(+). Up to now, about 120 mA of H(+), 83 mA of D(+), 50 mA of O(+), 63 mA of N(+), 70 mA of Ar(+), and 65 mA of He(+) extracted at 50 kV through a φ 6 mm aperture were produced by the PMECRs at PKU. Their rms emittances are less than 0.2 π mm mrad. Tungsten samples were irradiated by H(+) or He(+) beam extracted from this ion source and H∕He holes and bubbles have been observed on the samples. A method to produce a high intensity H∕He mixed beam to study synergistic effect is developed for nuclear material irradiation. To design a He(+) beam injector for coupled radio frequency quadruple and SFRFQ cavity, He(+) beam transmission experiments were carried out on PKU low energy beam transport test bench and the transmission was less than 50%. It indicated that some electrode modifications must be done to decrease the divergence of He(+) beam.

Bcl-2 inhibitors potentiate the cytotoxic effects of radiation in Bcl-2 overexpressing radioresistant tumor cells

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

Hara, Takamitsu; Omura-Minamisawa, Motoko; Chao Cheng

Purpose: Bcl-2, an inhibitor of apoptosis frequently shows elevated expression in human tumors, thus resulting in resistance to radiation therapy. Therefore, inhibiting Bcl-2 function may enhance the radiosensitivity of tumor cells. Tetrocarcin A (TC-A) and bcl-2 antisense oligonucleotides exhibit antitumor activity by inhibiting Bcl-2 function and transcription, respectively. We investigated whether these antitumor agents would enhance the cytotoxic effects of radiation in tumor cells overexpressing Bcl-2. Methods and materials: We used HeLa/bcl-2 cells, a stable Bcl-2-expressing cell line derived from wild-type HeLa (HeLa/wt) cells. Cells were incubated with TC-A and bcl-2 antisense oligonucleotides for 24 h after irradiation, and cellmore » viability was then determined. Apoptotic cells were quantified by flow cytometric assay. Results: The HeLa/bcl-2 cells were more resistant to radiation than HeLa/wt cells. At concentrations that are not inherently cytotoxic, both TC-A and bcl-2 antisense oligonucleotides increased the cytotoxic effects of radiation in HeLa/bcl-2 cells, but not in HeLa/wt cells. However, in HeLa/bcl-2 cells, additional treatment with TC-A in combination with radiation did not significantly increase apoptosis. Conclusions: The present results suggest that TC-A and bcl-2 antisense oligonucleotides reduce radioresistance of tumor cells overexpressing Bcl-2. Therefore, a combination of radiotherapy and Bcl-2 inhibitors may prove to be a useful therapeutic approach for treating tumors that overexpress Bcl-2.« less

[Essential oil from Artemisia lavandulaefolia induces apoptosis and necrosis of HeLa cells].

PubMed

Zhang, Lu-min; Lv, Xue-wei; Shao, Lin-xiang; Ma, Yan-fang; Cheng, Wen-zhao; Gao, Hai-tao

2013-12-01

To investigate the effects of Artemisia lavandulaefolia essential oil on apoptosis and necrosis of HeLa cells. Cell viability was assayed using MTT method. The morphological and structure alterations in HeLa cells were observed by microscopy. Furthermore, cell apoptosis was measured by DNA Ladder and flow cytometry. DNA damage was measured by comet assay, and the protein expression was examined by Western blot analysis. MTT assay displayed essential oil from Artemisia lavandulaefolia could inhibit the proliferation of HeLa cells in a dose-dependent manner. After treated with essential oil of Artemisia lavadulaefolia for 24 h, HeLa cells in 100 and 200 microg/mL experiment groups exhibited the typical morphology changes of undergoing apoptosis, such as cell shrinkage and nucleus chromatin condensed. However, the cells in the 400 microg/mL group showed the necrotic morphology changes including cytomembrane rupture and cytoplasm spillover. In addition, DNA Ladder could be demonstrated by DNA electrophoresis in each experiment group. Apoptosis peak was also evident in flow cytometry in each experiment group. After treating the HeLa cells with essential oil of Artemisia lavadulaefolia for 6 h, comet tail was detected by comet assay. Moreover, western blotting analysis showed that caspase-3 was activated and the cleavage of PARP was inactivated. Essential oil from Artemisia lavadulaefolia can inhibit the proliferation of HeLa cells in vitro. Low concentration of essential oil from Artemisia lavadulaefolia can induce apoptosis, whereas high concentration of the compounds result in necrosis of HeLa cells. And,the mechanism may be related to the caspase-3-mediated-PARP apoptotic signal pathway.

Critical Assessment of Theoretical Methods for Li3+ Collisions with He at Intermediate and High Impact Energies

NASA Astrophysics Data System (ADS)

Belkić, Dževad; Mančev, Ivan; Milojevićb, Nenad

2013-09-01

The total cross sections for the various processes for Li3+-He collisions at intermediate-to-high impact energies are compared with the corresponding theories. The possible reasons for the discrepancies among various theoretical predictions are thoroughly discussed. Special attention has been paid to single and double electron capture, simultaneous transfer and ionization, as well as to single and double ionization.

The moon: An abundant source of clean and safe fusion fuel for the 21st century

NASA Technical Reports Server (NTRS)

Kulcinski, G. L.; Schmitt, Harrison H.

1988-01-01

It is shown how helium-3 can be obtained from the moon and how its use in fusion reactors can benefit the inhabitants of this planet. The physics and technology issues associated with the use of He-3 is addressed. A description is given of He-3 distribution on the moon and of methods which could be used to retrieve it.

Activity Monitors Help Users Get Optimum Sun Exposure

NASA Technical Reports Server (NTRS)

2015-01-01

Goddard scientist Shahid Aslam was investigating alternative methods for measuring extreme ultraviolet radiation on the Solar Dynamics Observatory when he hit upon semiconductors that measured wavelengths pertinent to human health. As a result, he and a partner established College Park, Maryland-based Sensor Sensor LLC and developed UVA+B SunFriend, a wrist monitor that lets people know when they've received their optimal amounts of sunlight for the day.

A method for calculating the gas volume proportions and inhalation temperature of inert gas mixtures allowing reaching normothermic or hypothermic target body temperature in the awake rat.

PubMed

Abraini, Jacques H; David, Hélène N; Blatteau, Jean-Éric; Risso, Jean Jacques; Vallée, Nicolas

2017-01-01

The noble gases xenon (Xe) and helium (He) are known to possess neuroprotective properties. Xe is considered the golden standard neuroprotective gas. However, Xe has a higher molecular weight and lower thermal conductivity and specific heat than those of nitrogen, the main diluent of oxygen (O2) in air, conditions that could impair or at least reduce the intrinsic neuroprotective properties of Xe by increasing the critical care patient's respiratory workload and body temperature. In contrast, He has a lower molecular weight and higher thermal conductivity and specific heat than those of nitrogen, but is unfortunately far less potent than Xe at providing neuroprotection. Therefore, combining Xe with He could allow obtaining, depending on the gas inhalation temperature and composition, gas mixtures with neutral or hypothermic properties, the latter being advantageous in term of neuroprotection. However, calculating the thermal properties of a mixture, whatever the substances - gases, metals, rubbers, etc . - is not trivial. To answer this question, we provide a graphical method to assess the volume proportions of Xe, He and O2 that a gas mixture should contain, and the inhalation temperature to which it should be administered to allow a clinician to maintain the patient at a target body temperature.

Digital simulation of staining in histopathology multispectral images: enhancement and linear transformation of spectral transmittance.

PubMed

Bautista, Pinky A; Yagi, Yukako

2012-05-01

Hematoxylin and eosin (H&E) stain is currently the most popular for routine histopathology staining. Special and/or immuno-histochemical (IHC) staining is often requested to further corroborate the initial diagnosis on H&E stained tissue sections. Digital simulation of staining (or digital staining) can be a very valuable tool to produce the desired stained images from the H&E stained tissue sections instantaneously. We present an approach to digital staining of histopathology multispectral images by combining the effects of spectral enhancement and spectral transformation. Spectral enhancement is accomplished by shifting the N-band original spectrum of the multispectral pixel with the weighted difference between the pixel's original and estimated spectrum; the spectrum is estimated using M < N principal component (PC) vectors. The pixel's enhanced spectrum is transformed to the spectral configuration associated to its reaction to a specific stain by utilizing an N × N transformation matrix, which is derived through application of least mean squares method to the enhanced and target spectral transmittance samples of the different tissue components found in the image. Results of our experiments on the digital conversion of an H&E stained multispectral image to its Masson's trichrome stained equivalent show the viability of the method.

Theoretical investigation of the relative stability of Na{sup +}He{sub n} (n = 2–24) clusters: Many-body versus delocalization effects

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

Issaoui, Noureddine, E-mail: issaoui-noureddine@yahoo.fr; Abdessalem, Kawther; Ghalla, Houcine

2014-11-07

The solvation of the Na{sup +} ion in helium clusters has been studied theoretically using optimization methods. A many-body empirical potential was developed to account for Na{sup +}–He and polarization interactions, and the most stable structures of Na{sup +}He{sub n} clusters were determined using the basin-hopping method. Vibrational delocalization was accounted for using zero-point energy corrections at the harmonic or anharmonic levels, the latter being evaluated from quantum Monte Carlo simulations for spinless particles. From the static perspective, many-body effects are found to play a minor role, and the structures obtained reflect homogeneous covering up to n = 10, followedmore » by polyicosahedral packing above this size, the cluster obtained at n = 12 appearing particularly stable. The cationic impurity binds the closest helium atoms sufficiently to negate vibrational delocalization at small sizes. However, this snowball effect is obliterated earlier than shell completion, the nuclear wavefunctions of {sup 4}He{sub n}Na{sup +} with n = 5–7, and n > 10 already exhibiting multiple inherent structures. The decrease in the snowball size due to many-body effects is consistent with recent mass spectrometry measurements.« less

UPTAKE OF RADIONUCLIDE METALS BY SPME FIBERS

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

Duff, M; S Crump, S; Robert02 Ray, R

2006-08-28

The Federal Bureau of Investigation (FBI) Laboratory currently does not have on site facilities for handling radioactive evidentiary materials and there are no established FBI methods or procedures for decontaminating high explosive (HE) and fire debris (FD) evidence while maintaining evidentiary value. One experimental method for the isolation of HE and FD residue involves using solid phase microextraction or SPME fibers to remove residue of interest. Due to their high affinity for organics, SPME fibers should have little affinity for most metals. However, no studies have measured the affinity of radionuclides for SPME fibers. The focus of this research wasmore » to examine the affinity of dissolved radionuclide ({sup 239/240}Pu, {sup 238}U, {sup 237}Np, {sup 85}Sr, {sup 133}Ba, {sup 137}Cs, {sup 60}Co and {sup 226}Ra) and stable radionuclide surrogate metals (Sr, Co, Ir, Re, Ni, Ba, Cs, Nb, Zr, Ru, and Nd) for SPME fibers at the exposure conditions that favor the uptake of HE and FD residues. Our results from radiochemical and mass spectrometric analyses indicate these metals have little measurable affinity for these SPME fibers during conditions that are conducive to HE and FD residue uptake with subsequent analysis by liquid or gas phase chromatography with mass spectrometric detection.« less

SOLID PHASE MICROEXTRACTION SAMPLING OF HIGH EXPLOSIVE RESIDUES IN THE PRESENCE OF RADIONUCLIDES AND RADIONUCLIDE SURROGATE METALS

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

Duff, M; S Crump, S; Robert02 Ray, R

2007-04-13

The Federal Bureau of Investigation (FBI) Laboratory currently does not have on site facilities for handling radioactive evidentiary materials and there are no established FBI methods or procedures for decontaminating high explosive (HE) evidence while maintaining evidentiary value. One experimental method for the isolation of HE residue involves using solid phase microextraction or SPME fibers to remove residue of interest. Due to their high affinity for organics, SPME fibers should have little affinity for most metals. However, no studies have measured the affinity of radionuclides for SPME fibers. The focus of this research was to examine the affinity of dissolvedmore » radionuclide ({sup 239/240}Pu, {sup 238}U, {sup 237}Np, {sup 85}Sr, {sup 133}Ba, {sup 137}Cs, {sup 60}Co and {sup 226}Ra) and stable radionuclide surrogate metals (Sr, Co, Ir, Re, Ni, Ba, Cs, Nb, Zr, Ru, and Nd) for SPME fibers at the exposure conditions that favor the uptake of HE residues. Our results from radiochemical and mass spectrometric analyses indicate these metals have little measurable affinity for these SPME fibers during conditions that are conducive to HE residue uptake with subsequent analysis by liquid or gas phase chromatography with mass spectrometric detection.« less

The origins of scientific cinematography and early medical applications.

PubMed

Barboi, Alexandru C; Goetz, Christopher G; Musetoiu, Radu

2004-06-08

To examine the neurologic cinematographic contributions of Gheorghe Marinescu. Near the end of the 19th century, cinematography developed and was immediately recognized as a new technique applicable to medical documentation. After studying with several prominent European neurologists and deeply influenced by Jean-Martin Charcot, Marinescu returned to Bucharest in 1897 and applied moving picture techniques to the study of neurologic patients. The Romanian State Archives were researched for original Marinescu films, and related publications were translated from Romanian and French. Between 1899 and 1902, Marinescu perfected the use of cinematography as a research method in neurosciences and published five articles based on cinematographic documents. He focused his studies particularly on organic gait disorders, locomotor ataxia, and hysteria. He adapted Charcot's method of lining up several patients with the same disorder and showing them together to permit appreciation of archetypes and formes frustes. He decomposed the moving pictures into sequential tracings for publication. He documented treatment results with cases filmed before and after therapy. Processed and digitized excerpts of these films accompany this manuscript. Marinescu's cinematographic studies led to several original contributions in clinical neurology. Remaining film archives include examples of many neurologic diseases, his examination techniques, and the working medical environment of the young founder of the Romanian school of neurology.

Informing cancer patient based on his type of personality:The self-sacrificing patient.

PubMed

Kallergis, George

2015-01-01

Imparting the bad news has become a hard task for the doctor, and is usually perceived as unpleasant by the patient to whom the bad news is revealed. It is vital that the physician's approach be tailored to the cancer patient's personality. Gathering by the informing process protocols already suggested the hardest step for the doctors to take is empathic understanding which, presupposes tailoring to the individual's needs. The aim of this article was to describe the self-sacrificing type of personality thoroughly, so that any physician can make a diagnosis and tailor the information strategy to their needs. As method of research was used the qualitative method through groups with doctors and nurses, while research within groups lasted for 5 years. Assessing the denial mechanism is hard for a person that regards disease as punishment and propitiation. The physician must mobilize his countertransference, the sense he gets from the discussions with the patient and their overall communication. If he finds that the patient has self-control, then the approach of imparting the news resembles that of the controlling-orderly personality. If he ascertains that the patient has a lasting embarrassment, he should be more careful and impart the news gradually, his approach resembling that of the dependent person.

Prospects for Practical Laser Ablation U/Pb and (U-Th)/He Double-Dating (LADD) of Detrital Apatite

NASA Astrophysics Data System (ADS)

Horne, A.; Hodges, K. V.; Van Soest, M. C.

2017-12-01

A laser ablation micro-analytical technique for (U-Th)/He dating has been shown to be an effective approach to the thermochronologic study of detrital zircons (Tripathy-Lang et al., J. Geophys. Res., 2013), while Evans et al. (J. Anal. At. Spectrom., 2015) and Horne et al. (Geochim. Cosmochim. Acta, 2016) demonstrated how the technique could be modified to enable laser ablation U/Pb and (U-Th)/He double-dating (LADD) of detrital zircon and titanite. These successes beg the question of whether or not LADD is viable for another commonly encountered detrital mineral: apatite. Exploratory LADD studies in Arizona State University's Group 18 Laboratories - using Durango fluorapatite, apatite from the Fish Canyon tuff, and detrital apatite from modern fluvial sediments in the eastern Sierra Nevada of California - illustrate that the method is indeed viable for detrital apatite. However, the method may not be appropriate for all detrital samples. For example, many apatite grains encountered in detrital samples from young orogenic settings have low concentrations of U and Th and small crystal sizes. This can lead to imprecise laser ablation (U-Th)/He dates, especially for very young grains potentially obscuring or inhibiting relevant interpretations of the data set.

Cytotoxicity of Sargassum angustifolium Partitions against Breast and Cervical Cancer Cell Lines

PubMed Central

Vaseghi, Golnaz; Sharifi, Mohsen; Dana, Nasim; Ghasemi, Ahmad; Yegdaneh, Afsaneh

2018-01-01

Background: Marine organisms produce a variety of compounds with pharmacological activities including anticancer effects. This study attempt to find cytotoxicity of hexane (HEX), dichloromethane (DCM), and butanol (BUTOH) partitions of Sargassum angustifolium. Materials and Methods: S. angustifolium was collected from Bushehr, a Southwest coastline of Persian Gulf. The plant was extracted by maceration with methanol-ethyl acetate. The extract was evaporated under vacuum and partitioned by Kupchan method to yield HEX, DCM, and BUTOH partitions. The cytotoxic activity of the extract (150, 450, and 900 μg/ml) was investigated against MCF-7 (breast cancer), HeLa (cervical cancer), and human umbilical vein endothelial cells cell lines by mitochondrial tetrazolium test assay after 72 h. Results: The cell survivals of HeLa and MCF-7 cell were decreased by increasing the concentration of extracts from 150 μg/ml to 900 μg/ml. The median growth inhibitory concentration value of HEX partition was 71 and 77 μg/ml against HeLa and MCF-7, dichloromethane partition was 36 and 88 μg/ml against HeLa and MCF-7, respectively. BUTOH partition was 25 μg/ml against MCF-7. Conclusion: This study reveals that different partitions of S. angustifolium have cytotoxic activity against cancer cell lines. PMID:29657928

(U-Th)/He dating and He diffusion in calcite from veins and breccia

NASA Astrophysics Data System (ADS)

Gautheron, C.; Cros, A.; Pagel, M.; Berthet, P.; Tassan-Got, L.; Douville, E.; Pinna-Jamme, R.; Sarda, P.

2013-12-01

Knowledge of He retention in crystalline calcite is mandatory to estimate the possibility of (U-Th)/He dating of calcite. To this aim, fault-filling calcite crystals from the Eocene/Oligocene Gondrecourt graben, Paris Basin, Eastern France, have been sampled, based on their relatively old, Eocene-Oligocene, precipitation age and cold thermal history (<40°C since precipitation). The samples were sorted into three main tectonic and morphological groups, including successively (1) micro-fracture calcites, (2) breccia and associated geodic calcites, and (3) vein and associated geodic calcites. (U-Th)/He dating of 63 calcite fragments yields ages dispersed from 0.2×0.02 to 35.8×2.7 Ma, as well as two older dates of 117×10 and 205×28 Ma (1s). These He ages correlate to grain chemistry, such as to Sr and ΣREE concentrations or (La/Yb)N ratios, and these correlations probably reflect the evolution of parent fluid. Only the oldest He ages are in agreement with the He-retentive character of calcite as determined by Copeland et al. (2007), and these ages were obtained for the most recently precipitated crystals. To better understand the large He-age scatter and why calcites precipitated earlier show younger ages, He diffusion experiments have been conducted on 10 Gondrecourt calcite fragments from 3 samples with He ages of 0.2 to 6 Ma. In addition, a crystallographic investigation by X-Ray Diffraction (XRD) performed on similar samples reveals that the crystal structure evolves with increasing temperature, showing with micro-cracks and cleavage opening. These XRD results indicate that, in fault-filling calcite, He retention is controlled by multiple diffusion domains (MDD, Lovera et al., 1991) with various sizes, and therefore, evolves through time with strong consequences on (U-Th)/He age. We thus interpret the Gondrecourt calcite (U-Th)/He age scatter of older samples as a consequence of cleavage opening due to a succession of calcite crystallization phases related to the deformation history. Finally, we propose that the crystallization age of a calcite crystal with a known thermal history can nevertheless be retrieved by the (U-Th)/He method provided the He diffusion pattern can be measured by careful step-heating degassing analysis. Copeland, P., Watson, E.B., Urizar, S.C., Patterson, D., Lapen, T.J., 2007. Alpha thermochronology of carbonates. Geochim. Cosmochim. Acta, 71: 4488-4511. Cros, A. Gautheron, C., Pagel, M., Berthet, P., Tassan-Got, L., Douville, E., Pinna-Jamme, R., Sarda, P., submitted GCA, He behavior in calcite filling viewed by (U-Th)/He dating, He diffusion and crystallographic studies. Lovera, O.M., Richter, F.M., Harrison, T.M., 1991. Diffusion domains determined by 39Ar released during step heating. Journal of Geophysical Research, 96: 2057-2069.

Automated Blood Pressure Measurement

NASA Technical Reports Server (NTRS)

1978-01-01

The Vital-2 unit pictured is a semi-automatic device that permits highly accurate blood pressure measurement, even by untrained personnel. Developed by Meditron Instrument Corporation, Milford, New Hampshire, it is based in part on NASA technology found in a similar system designed for automatic monitoring of astronauts' blood pressure. Vital-2 is an advancement over the familiar arm cuff, dial and bulb apparatus customarily used for blood pressure checks. In that method, the physician squeezes the bulb to inflate the arm cuff, which restricts the flow of blood through the arteries. As he eases the pressure on the arm, he listens, through a stethoscope, to the sounds of resumed blood flow as the arteries expand and contract. Taking dial readings related to sound changes, he gets the systolic (contracting) and diastolic (expanding) blood pressure measurements. The accuracy of the method depends on the physician's skill in interpreting the sounds. Hospitals sometimes employ a more accurate procedure, but it is "invasive," involving insertion of a catheter in the artery.

The work of local culture: Wendell Berry and communities as the source of farming knowledge.

PubMed

Filipiak, Jeffrey

2011-01-01

When Wendell Berry and others criticize contemporary agriculture, their arguments are often dismissed as naive and grounded in longstanding agrarian myth, rather than engagement with contemporary problems. But Berry's proposals developed in response to a series of learning methods he encountered, and options for advocacy he explored, during the 1960s and 1970s. Agricultural institutions sought to assign more power to institutionalized scientific knowledge, shrinking the role of farmers. Berry sought an alternative definition of knowledge, drawing upon his training as a writer, as well as his experiences with manual farm work and the methods of environmentalist organic growers. He eventually concluded that only a community of farmers could produce and store effective knowledge and insisted that knowledge must be tacit -- largely situated in locality, skills, and culture. His ideas had little influence on most people employed in contemporary agriculture. However, those ideas profoundly shape the work of sustainable food advocates, such as Michael Pollan, who like Berry fear reductionism and celebrate the values of traditions.

Second sound tracking system

NASA Astrophysics Data System (ADS)

Yang, Jihee; Ihas, Gary G.; Ekdahl, Dan

2017-10-01

It is common that a physical system resonates at a particular frequency, whose frequency depends on physical parameters which may change in time. Often, one would like to automatically track this signal as the frequency changes, measuring, for example, its amplitude. In scientific research, one would also like to utilize the standard methods, such as lock-in amplifiers, to improve the signal to noise ratio. We present a complete He ii second sound system that uses positive feedback to generate a sinusoidal signal of constant amplitude via automatic gain control. This signal is used to produce temperature/entropy waves (second sound) in superfluid helium-4 (He ii). A lock-in amplifier limits the oscillation to a desirable frequency and demodulates the received sound signal. Using this tracking system, a second sound signal probed turbulent decay in He ii. We present results showing that the tracking system is more reliable than those of a conventional fixed frequency method; there is less correlation with temperature (frequency) fluctuation when the tracking system is used.

Charge Transfer Dissociation of Complex Oligosaccharides: Comparison with Collision-Induced Dissociation and Extreme Ultraviolet Dissociative Photoionization

NASA Astrophysics Data System (ADS)

Ropartz, David; Li, Pengfei; Fanuel, Mathieu; Giuliani, Alexandre; Rogniaux, Hélène; Jackson, Glen P.

2016-10-01

The structural characterization of oligosaccharides still challenges the field of analytical chemistry. Tandem mass spectrometry offers many advantages toward this aim, although the generic fragmentation method (low-energy collision-induced dissociation) shows clear limitations and is often insufficient to retrieve some essential structural information on these molecules. In this work, we present the first application of helium charge transfer dissociation (He-CTD) to characterize the structure of complex oligosaccharides. We compare this method with low-energy collision-induced dissociation and extreme-ultraviolet dissociative photoionization (XUV-DPI), which was shown previously to ensure the successful characterization of complex glycans. Similarly to what could be obtained by XUV-DPI, He-CTD provides a complete description of the investigated structures by producing many informative cross-ring fragments and no ambiguous fragmentation. Unlike XUV-DPI, which is performed at a synchrotron source, He-CTD has the undeniable advantage of being implementable in a conventional benchtop ion trap in a conventional laboratory setting.

Total Reaction Cross Section Excitation Function Studies for 6He Interaction with 181Ta, 59Co, natSi, 9Be Nuclei

NASA Astrophysics Data System (ADS)

Sobolev, Yu. G.; Penionzhkevich, Yu. E.; Borcea, C.; Demekhina, N. A.; Eshanov, A. G.; Ivanov, M. P.; Kabdrakhimova, G. D.; Kabyshev, A. M.; Kugler, A.; Kuterbekov, K. A.; Lukyanov, K. V.; Maj, A.; Maslov, V. A.; Negret, A.; Skobelev, N. K.; Testov, D.; Trzaska, W. H.; Voskobojnik, E. I.; Zemlyanaya, E. V.

2015-06-01

Total reaction cross section excitation functions σR(E) were measured for 6He secondary beam particles on 181Ta, 59Co, natSi and 9Be targets in a wide energy range by direct and model-independent method. This experimental method was based on prompt n-γ 4π-technique applied in event-by event mode. A high efficiency CsI(Tl) γ-spectrometer was used for the detection of reaction products (prompt γ-quanta and neutrons) accompanying each reaction event. Using the ACCULINNA fragment-separator 6He fragments (produced by 11B primary beam with 9Be target) are separated and transported to n-γ shielded experimental cave at FLNR JINR. The measured total reaction cross section data σR(E) for the above mentioned reactions are compared with a theoretical calculation based on the optical potential with the real part having the double-folding form.

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

Wang, C. L.; Funk, L. L.; Riedel, R. A.

3He gas based neutron linear-position-sensitive detectors (LPSDs) have been applied for many neutron scattering instruments. Traditional Pulse-Height Analysis (PHA) for Neutron-Gamma Discrimination (NGD) resulted in the neutron-gamma efficiency ratio on the orders of 10 5-10 6. The NGD ratios of 3He detectors need to be improved for even better scientific results from neutron scattering. Digital Signal Processing (DSP) analyses of waveforms were proposed for obtaining better NGD ratios, based on features extracted from rise-time, pulse amplitude, charge integration, a simplified Wiener filter, and the cross-correlation between individual and template waveforms of neutron and gamma events. Fisher linear discriminant analysis (FLDA)more » and three multivariate analyses (MVAs) of the features were performed. The NGD ratios are improved by about 10 2-10 3 times compared with the traditional PHA method. Finally, our results indicate the NGD capabilities of 3He tube detectors can be significantly improved with subspace-learning based methods, which may result in a reduced data-collection time and better data quality for further data reduction.« less

Determination of Protein Expression Level in Cultured Cells by Immunocytochemistry on Paraffin-embedded Cell Blocks.

PubMed

Poojan, Shiv; Kim, Han-Seong; Yoon, Ji-Woon; Sim, Hye Won; Hong, Kyeong-Man

2018-05-20

Immunofluorescent staining is currently the method of choice for determination of protein expression levels in cell-culture systems when morphological information is also necessary. The protocol of immunocytochemical staining on paraffin-embedded cell blocks, presented herein, is an excellent alternative to immunofluorescent staining on non-paraffin-embedded fixed cells. In this protocol, a paraffin cell block from HeLa cells was prepared using the thromboplastin-plasma method, and immunocytochemistry was performed for the evaluation of two proliferation markers, CKAP2 and Ki-67. The nuclei and cytoplasmic morphology of the HeLa cells were well preserved in the cell-block slides. At the same time, the CKAP2 and Ki-67 staining patterns in the immunocytochemistry were quite similar to those in immunohistochemical staining in paraffin cancer tissues. With modified cell-culture conditions, including pre-incubation of HeLa cells under serum-free conditions, the effect could be evaluated while preserving architectural information. In conclusion, immunocytochemistry on paraffin-embedded cell blocks is an excellent alternative to immunofluorescent staining.

KLL dielectronic recombination resonant strengths of He-like up to O-like xenon ions

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

Yao, K.; Geng, Z.; Xiao, J.

2010-02-15

In this work, the KLL dielectronic recombination (DR) resonant strengths of He- through to O-like Xe ions were studied, both through experiment and calculation. The experiments were done using a fast electron beam-energy scanning technique at the Shanghai electron beam ion trap. The calculations were done by using the flexible atomic code (FAC), in which the relativistic configuration interaction (RCI) method was employed. For the total resonant strengths, the present experimental and theoretical results for He-, Be-, B-, C-, N-, and O-like Xe ions agree within experimental uncertainties (about 9%). But the experimental result for Li-like Xe is 14% highermore » than the calculation. The present FAC calculations of the total DR strengths were compared with the available previous calculations, using RCI or multiconfiguration Dirac-Fock (MCDF) methods, and the agreement was very good. In this work, some intermediate-state resolved KLL DR strengths were also obtained and compared with theoretical results, and more discrepancies were revealed.« less

40 CFR 152.90 - The selective method.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 24 2014-07-01 2014-07-01 false The selective method. 152.90 Section... Data Submitters' Rights § 152.90 The selective method. An applicant may comply with this subpart by... summarizes the procedures that an applicant must follow if he chooses the selective method of demonstrating...

Serum and ascitic fluid serotonin levels and 5-hydroxyindoleacetic acid urine excretion in the liver of cirrhotic patients with encephalopathy.

PubMed

Chojnacki, C; Walecka-Kapica, E; Stepien, A; Pawlowicz, M; Wachowska-Kelly, P; Chojnacki, J

2013-01-01

The excess and deficit of serotonin can be the cause of somatic and mental disorders. The aim of this study was to evaluate serotonin levels in blood and ascitic fluid as well as excretion of 5-hydroxyindoleacetic acid (5-HIAA) in urine in patients with hepatic encephalopathy (HE). The study included 75 alcoholic cirrhotic patients divided into 3 groups (HE1, HE2, HE3), 25 patients each, with grade 1, 2 and 3 of hepatic encephalopathy according to West-Haven classification. The control group (C) included 25 clinically healthy volunteers. Venous blood and ascitic fluid were collected in fasting. On the same day a 24-hour urine collection was performed. Immunoenzymatic method was used to determine the serotonin level in serum and ascitic fluid, and 5-HIAA in urine (IBL-RE-59121, RE-59131). In the control group, mean serum serotonin level (ng/ml) was 155.5 ± 38.1 and in the 3 study groups: HE1 - 175.2 ± 32.4 (NS), HE2 - 137.2 ± 28.6 (NS), HE3 - 108.3 ± 46.3 (p<0.001). Serotonin concentration in ascitic fluid was on the average about 25% of its level in serum. The excretion of 5-HIAA in urine (mg/24h) in all groups, was: C - 5.9 ± 2.1, HE1 - 5.8 ± 1.8 (NS), HE2 - 4.8 ± 1.2(NS), HE3 - 4.3 ± 1.3 (p<0.05). The results of our study indicate that serum and ascitic fluid level of serotonin and urine excretion of 5-HIAA depends on the grade of hepatic encephalopathy. In patients with severe hepatic encephalopathy serotonin concentration in blood is decreased which can affect some clinical manifestation of this disease.

Leukemia-associated gene MLAA-34 reduces arsenic trioxide-induced apoptosis in HeLa cells via activation of the Wnt/β-catenin signaling pathway.

PubMed

Zhang, Pengyu; Zhao, Xuan; Zhang, Wenjuan; He, Aili; Lei, Bo; Zhang, Wanggang; Chen, Yinxia

2017-01-01

Our laboratory previously used the SEREX method in U937 cells and identified a novel leukemia-associated gene MLAA-34, a novel splice variant of CAB39L associated with acute monocytic leukemia, that exhibited anti-apoptotic activities in U937 cells. Whether MLAA-34 has an anti-apoptotic role in other tumor cells has not yet been reported. We explored whether MLAA-34 exhibited anti-apoptotic effects in HeLa cervical cancer cells and the possible mechanism of action. We generated a HeLa cell line stably expressing MLAA-34 and found that MLAA-34 overexpression had no effect on the growth, apoptosis and cell cycle of HeLa cells. However, upon treatment with arsenic trioxide (ATO) to induce apoptosis, the cell viability and colony formation ability of ATO-treated MLAA-34 stable HeLa cells were significantly higher than that of ATO-treated controls, and the apoptosis rate and proportion of G2/M cells also decreased. We found that ATO treatment of HeLa cells resulted in significant decreases in the expression of β-catenin mRNA and protein and the downstream target factors c-Myc, cyclin B1, and cyclin D1 in the Wnt signaling pathway. Notably, ATO-treated MLAA-34 stable HeLa cells showed a significant reduction in the ATO-mediated downregulation of these factors. In addition, MLAA-34 overexpression significantly increased the expression of nuclear β-catenin protein in ATO-treated cells compared with HeLa cells treated only with ATO. Thus, here we have found that the Wnt/β-catenin signaling pathway is involved in ATO-induced apoptosis in HeLa cells. MLAA-34 reduces ATO-induced apoptosis and G2/M arrest, and the anti-apoptotic effect may be achieved by activating the Wnt/β-catenin signaling pathway in HeLa cells.

Merging of a CO WD and a He-rich WD to produce a type Ia supernovae

NASA Astrophysics Data System (ADS)

Liu, D.; Wang, B.; Wu, C.; Han, Z.

2017-10-01

Context. Although type Ia supernovae (SNe Ia) play a key role in astrophysics, the companions of the exploding carbon-oxygen white dwarfs (CO WDs) are still not completely identified. It has been suggested recently that a He-rich WD (a He WD or a hybrid HeCO WD) that merges with a CO WD may produce an SN Ia. This theory was based on the double-detonation model, in which the shock compression in the CO core caused by the surface explosion of the He-rich shell might lead to the explosion of the whole CO WD. However, so far, very few binary population synthesis (BPS) studies have been made on the merger scenario of a CO WD and a He-rich WD in the context of SNe Ia. Aims: We aim to systematically study the Galactic birthrates and delay-time distributions of SNe Ia based on the merger scenario of a CO WD and a He-rich WD. Methods: We performed a series of Monte Carlo BPS simulations to investigate the properties of SNe Ia from the merging of a CO WD and a He-rich WD based on the Hurley rapid binary evolution code. We also considered the influence of different metallicities on the final results. Results: From our simulations, we found that no more than 15% of all SNe Ia stem from the merger scenario of a CO WD and a He-rich WD, and their delay times range from 110 Myr to the Hubble time. This scenario mainly contributes to SN Ia explosions with intermediate and long delay times. The present work indicates that the merger scenario of a CO WD and a He-rich WD can roughly reproduce the birthrates of SN 1991bg-like events, and cover the range of their delay times. We also found that SN Ia birthrates from this scenario would be higher for the cases with low metallicities.

Leukemia-associated gene MLAA-34 reduces arsenic trioxide-induced apoptosis in HeLa cells via activation of the Wnt/β-catenin signaling pathway

PubMed Central

Zhao, Xuan; Zhang, Wenjuan; He, Aili; Lei, Bo; Zhang, Wanggang; Chen, Yinxia

2017-01-01

Our laboratory previously used the SEREX method in U937 cells and identified a novel leukemia-associated gene MLAA-34, a novel splice variant of CAB39L associated with acute monocytic leukemia, that exhibited anti-apoptotic activities in U937 cells. Whether MLAA-34 has an anti-apoptotic role in other tumor cells has not yet been reported. We explored whether MLAA-34 exhibited anti-apoptotic effects in HeLa cervical cancer cells and the possible mechanism of action. We generated a HeLa cell line stably expressing MLAA-34 and found that MLAA-34 overexpression had no effect on the growth, apoptosis and cell cycle of HeLa cells. However, upon treatment with arsenic trioxide (ATO) to induce apoptosis, the cell viability and colony formation ability of ATO-treated MLAA-34 stable HeLa cells were significantly higher than that of ATO-treated controls, and the apoptosis rate and proportion of G2/M cells also decreased. We found that ATO treatment of HeLa cells resulted in significant decreases in the expression of β-catenin mRNA and protein and the downstream target factors c-Myc, cyclin B1, and cyclin D1 in the Wnt signaling pathway. Notably, ATO-treated MLAA-34 stable HeLa cells showed a significant reduction in the ATO-mediated downregulation of these factors. In addition, MLAA-34 overexpression significantly increased the expression of nuclear β-catenin protein in ATO-treated cells compared with HeLa cells treated only with ATO. Thus, here we have found that the Wnt/β-catenin signaling pathway is involved in ATO-induced apoptosis in HeLa cells. MLAA-34 reduces ATO-induced apoptosis and G2/M arrest, and the anti-apoptotic effect may be achieved by activating the Wnt/β-catenin signaling pathway in HeLa cells. PMID:29059232

Applications of the Hybrid Theory to the Scattering of Electrons from HE+ and Li++ and Resonances in these Systems

NASA Technical Reports Server (NTRS)

Bhatia, Anand K.

2008-01-01

Applications of the hybrid theory to the scattering of electrons from Ile+ and Li++ and resonances in these systems, A. K. Bhatia, NASA/Goddard Space Flight Center- The Hybrid theory of electron-hydrogen elastic scattering [I] is applied to the S-wave scattering of electrons from He+ and Li++. In this method, both short-range and long-range correlations are included in the Schrodinger equation at the same time. Phase shifts obtained in this calculation have rigorous lower bounds to the exact phase shifts and they are compared with those obtained using the Feshbach projection operator formalism [2], the close-coupling approach [3], and Harris-Nesbet method [4]. The agreement among all the calculations is very good. These systems have doubly-excited or Feshbach resonances embedded in the continuum. The resonance parameters for the lowest ' S resonances in He and Li+ are calculated and they are compared with the results obtained using the Feshbach projection operator formalism [5,6]. It is concluded that accurate resonance parameters can be obtained by the present method, which has the advantage of including corrections due to neighboring resonances and the continuum in which these resonances are embedded.

Automatic evaluation of skin histopathological images for melanocytic features

NASA Astrophysics Data System (ADS)

Koosha, Mohaddeseh; Hoseini Alinodehi, S. Pourya; Nicolescu, Mircea; Safaei Naraghi, Zahra

2017-03-01

Successfully detecting melanocyte cells in the skin epidermis has great significance in skin histopathology. Because of the existence of cells with similar appearance to melanocytes in hematoxylin and eosin (HE) images of the epidermis, detecting melanocytes becomes a challenging task. This paper proposes a novel technique for the detection of melanocytes in HE images of the epidermis, based on the melanocyte color features, in the HSI color domain. Initially, an effective soft morphological filter is applied to the HE images in the HSI color domain to remove noise. Then a novel threshold-based technique is applied to distinguish the candidate melanocytes' nuclei. Similarly, the method is applied to find the candidate surrounding halos of the melanocytes. The candidate nuclei are associated with their surrounding halos using the suggested logical and statistical inferences. Finally, a fuzzy inference system is proposed, based on the HSI color information of a typical melanocyte in the epidermis, to calculate the similarity ratio of each candidate cell to a melanocyte. As our review on the literature shows, this is the first method evaluating epidermis cells for melanocyte similarity ratio. Experimental results on various images with different zooming factors show that the proposed method improves the results of previous works.

Differentiation and Exploration of Model MACP for HE VER 1.0 on Prototype Performance Measurement Application for Higher Education

NASA Astrophysics Data System (ADS)

El Akbar, R. Reza; Anshary, Muhammad Adi Khairul; Hariadi, Dennis

2018-02-01

Model MACP for HE ver.1. Is a model that describes how to perform measurement and monitoring performance for Higher Education. Based on a review of the research related to the model, there are several parts of the model component to develop in further research, so this research has four main objectives. The first objective is to differentiate the CSF (critical success factor) components in the previous model, the two key KPI (key performance indicators) exploration in the previous model, the three based on the previous objective, the new and more detailed model design. The final goal is the fourth designed prototype application for performance measurement in higher education, based on a new model created. The method used is explorative research method and application design using prototype method. The results of this study are first, forming a more detailed new model for measurement and monitoring of performance in higher education, differentiation and exploration of the Model MACP for HE Ver.1. The second result compiles a dictionary of college performance measurement by re-evaluating the existing indicators. The third result is the design of prototype application of performance measurement in higher education.

Model building with wind and water: Friedrich Ahlborn's photo-optical flow analysis.

PubMed

Hinterwaldner, Inge

2015-02-01

Around 1900, several experimenters investigated turbulences in wind tunnels or water basins by creating visualizations. One of them, the German zoologist Friedrich Ahlborn (1858-1937), was familiar with the works by his contemporaries but he struck a new path. He combined three different kinds of photographs taken at the same time and showed the same situation in his water trough-but each in a different way. With this first basic operation, Ahlborn heuristically opened up a previously non-existent space for experimentation, analysis, and recombination. He generated an astonishing diversity of information by adopting the tactics of 'inversions' in which he interpreted one part of the experimental setup, or its results, in different ways. Between the variants of the 'autographs' which he developed, he defined areas of intersection to be able to translate results from individual records into each other. To this end, Ahlborn created other sets of visual artifacts such as drawn diagrams, three-dimensional wire frame constructions, and clay reliefs. His working method can be described as a cascading array of successive modeling steps, as elaborated by Eric Winsberg (1999), or of inscriptions in Bruno Latour's words (Latour, 1986). By examining Ahlborn's procedures closely we propose conceptualizations for the experimenter's various operations. Copyright © 2014 Elsevier Ltd. All rights reserved.

Role of non-Invasive Tests for the Early Detection of Cancer

Cancer.gov

Dr. Nickolas Papadopoulos is Professor of Oncology & Pathology and Director of Translational Genetics at the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins. He is internationally known as a co-discoverer of the genetic basis of the predisposition to hereditary nonpolyposis colon cancer (HNPCC), one of the most common hereditary forms of cancer, earlier in his career. He is known for the development of diagnostic tests and is considered an expert in cancer genetics and diagnostics. He was part of the interdisciplinary team that was first to sequence all of the protein coding genes, determine genetic alterations, and construct expression profiles of four common tumor types. Later, he was involved in the identification of genetic alterations that drive tumorigenesis in multiple tumor types. Noteworthy discoveries made by Dr. Papadopoulos include the identification of novel mutations in chromatin remodeling genes in ovarian clear cell carcinomas and pancreatic neuroendocrine tumors. He is a co-developer of sensitive methods for the detection of tumor DNA in liquid biopsy, and also the co-founder of two companies that develop diagnostics for cancer. Currently, he is focused on translating the genetic information derived from cancer genome analyses to clinical applications in early detection, diagnosis and monitoring of cancer. Dr. Papadopoulos received his PhD from the University of Texas McGovern Medical School in Houston.

The Michigan Binary Star Program

NASA Astrophysics Data System (ADS)

Lindner, Rudi P.

2007-07-01

At the end of the nineteenth century, William J. Hussey and Robert G. Aitken, both at Lick Observatory, began a systematic search for unrecorded binary stars with the aid of the 12" and 36" refracting telescopes at Lick Observatory. Aitken's work (and book on binary stars) are well known, Hussey's contributions less so. In 1905 Hussey, a Michigan engineering graduate, returned to direct the Ann Arbor astronomy program, and immediately he began to design new instrumentation for the study of binary stars and to train potential observers. For a time, he spent six months a year at the La Plata Observatory, where he discovered a number of new pairs and decided upon a major southern hemisphere campaign. He spent a decade obtaining the lenses for a large refractor, through the vicissitudes of war and depression. Finally, he obtained a site in South Africa, a 26" refractor, and a small corps of observers, but he died in London en route to fulfill his dream. His right hand man, Richard Rossiter, established the observatory and spent the next thirty years discovering and measuring binary stars: his personal total is a record for the field. This talk is an account of the methods, results, and utility of the extraordinary binary star factory in the veldt.

Hypoestoxide inhibits tumor growth in the mouse CT26 colon tumor model

PubMed Central

Ojo-Amaize, Emmanuel A; Cottam, Howard B; Oyemade, Olusola A; Okogun, Joseph I; Nchekwube, Emeka J

2007-01-01

AIM: To evaluate the effect of the natural diterpenoid, hypoestoxide (HE) on the growth of established colon cancer in mice. METHODS: The CT26.WT mouse colon carcinoma cell line was grown and expanded in vitro. Following the expansion, BALB/c mice were inoculated s.c. with viable tumor cells. After the tumors had established and developed to about 80-90 mm3, the mice were started on chemotherapy by oral administration of HE, 5-fluorouracil (5-FU) or combination. RESULTS: The antiangiogenic HE has previously been shown to inhibit the growth of melanoma in the B16F1 tumor model in C57BL/6 mice. Our results demonstrate that mean volume of tumors in mice treated with oral HE as a single agent or in combination with 5-FU, were significantly smaller (> 60%) than those in vehicle control mice (471.2 mm3 vs 1542.8 mm3, P < 0.01). The significant reductions in tumor burden resulted in pronounced mean survival times (MST) and increased life spans (ILS) in the treated mice. CONCLUSION: These results indicate that HE is an effective chemotherapeutic agent for colorectal cancer in mice and that HE may be used alone or in combination with 5-FU. PMID:17729410

(U-Th)/He ages of phosphates from Zagami and ALHA77005 Martian meteorites: Implications to shock temperatures

NASA Astrophysics Data System (ADS)

Min, Kyoungwon; Farah, Annette E.; Lee, Seung Ryeol; Lee, Jong Ik

2017-01-01

Shock conditions of Martian meteorites provide crucial information about ejection dynamics and original features of the Martian rocks. To better constrain equilibrium shock temperatures (Tequi-shock) of Martian meteorites, we investigated (U-Th)/He systematics of moderately-shocked (Zagami) and intensively shocked (ALHA77005) Martian meteorites. Multiple phosphate aggregates from Zagami and ALHA77005 yielded overall (U-Th)/He ages 92.2 ± 4.4 Ma (2σ) and 8.4 ± 1.2 Ma, respectively. These ages correspond to fractional losses of 0.49 ± 0.03 (Zagami) and 0.97 ± 0.01 (ALHA77005), assuming that the ejection-related shock event at ∼3 Ma is solely responsible for diffusive helium loss since crystallization. For He diffusion modeling, the diffusion domain radius is estimated based on detailed examination of fracture patterns in phosphates using a scanning electron microscope. For Zagami, the diffusion domain radius is estimated to be ∼2-9 μm, which is generally consistent with calculations from isothermal heating experiments (1-4 μm). For ALHA77005, the diffusion domain radius of ∼4-20 μm is estimated. Using the newly constrained (U-Th)/He data, diffusion domain radii, and other previously estimated parameters, the conductive cooling models yield Tequi-shock estimates of 360-410 °C and 460-560 °C for Zagami and ALHA77005, respectively. According to the sensitivity test, the estimated Tequi-shock values are relatively robust to input parameters. The Tequi-shock estimates for Zagami are more robust than those for ALHA77005, primarily because Zagami yielded intermediate fHe value (0.49) compared to ALHA77005 (0.97). For less intensively shocked Zagami, the He diffusion-based Tequi-shock estimates (this study) are significantly higher than expected from previously reported Tpost-shock values. For intensively shocked ALHA77005, the two independent approaches yielded generally consistent results. Using two other examples of previously studied Martian meteorites (ALHA84001 and Los Angeles), we compared Tequi-shock and Tpost-shock estimates. For intensively shocked meteorites (ALHA77005, Los Angeles), the He diffusion-based approach yield slightly higher or consistent Tequi-shock with estimations from Tpost-shock, and the discrepancy between the two methods increases as the intensity of shock increases. The reason for the discrepancy between the two methods, particularly for less-intensively shocked meteorites (Zagami, ALHA84001), remains to be resolved, but we prefer the He diffusion-based approach because its Tequi-shock estimates are relatively robust to input parameters.

The observatories and instruments of Tycho Brahe

NASA Astrophysics Data System (ADS)

Wolfschmidt, Gudrun

Tycho Brahe (1546-1601) was the most important observational astronomer until the invention of the telescope in 1608. By construction new instruments and devising new observing methods, Tycho succeeded in significantly increasing measurement accuracy: He increased the size of his instruments (e.g. a large wooden quadrant of diameter 5.4 m and a mural quadrant); he used metal and masonry rather than wood; he modified construction techniques to achieve greater stability; to provide shelter from the wind, his instruments were in subterranean nooks; his instruments were permanently and solidly mounted; for better angular readings, he developed new subdivisions and diopters (Tycho used transversals to obtain the greatest possible angular resolution readings. His instrumental sights (diopters) were specially designed to minimize errors); he carefully analysed all the errors (Tycho's aim was to reduce thethe uncertainty to less than one minute of arc); he used fundamental stars for the first time; he preferred measuring equatorial coordinates directly instead of using the zodiacal system, i.e. using the equatorial armillary sphere instead of the zodiacal armillary sphere; he tried a new measuring method with clocks and his mural quadrant (1582) for determining the right ascension; he took atmospheric refraction into account. Most of his high-accuracy instruments have been distroyed. Only two sextants, made by Jost Bürgi and Erasmus Habermel around 1600, still exist in the Narodny Technicky Muzeum (NTM) [National Technical Museum] in Prague. A model of the wooden quadrant is in the old observatory in Copenhagen, in the round tower. But we have good descriptions of the instruments (half circles of 2.3 m radius, quadrants up to 2 m radius including the mural quadrant, sextants up to 1.6 m, armillary spheres of 1.5 m radius and the great equatorial armillary sphere of 2.7 m, triquetrum and celestial globe of 1.5 m) in Tycho's book Astronomiae instauratae mechanica (Wandesburgi 1598, Nuremberg 1602). One of Tycho's instruments in original size was reconstructed in Oldenburg University and in the Steno Museum in Aarhus, Denmark. In Munich, in the Deutsches Museum's permanent astronomy exhibition (opened in 1992), the Uraniborg observatory and its instruments are shown at a scale of 1:10. A similar but larger model (scale 1:5) from the workshop of the Deutsches Museum was given to the Technical Museum in Malmø, Sweden. Tycho's later observatory Stjerneborg can be seen as a reconstruction on the island Hven (Ven/Sweden) with the original foundations for the instruments.

Application of P-wave hybrid theory to the scattering of electrons from He+ and resonances in He and H-

NASA Astrophysics Data System (ADS)

Bhatia, A. K.

2012-09-01

The P-wave hybrid theory of electron-hydrogen elastic scattering [Bhatia, Phys. Rev. A10.1103/PhysRevA.85.052708 85, 052708 (2012)] is applied to the P-wave scattering from He ion. In this method, both short-range and long-range correlations are included in the Schrödinger equation at the same time, by using a combination of a modified method of polarized orbitals and the optical potential formalism. The short-range-correlation functions are of Hylleraas type. It is found that the phase shifts are not significantly affected by the modification of the target function by a method similar to the method of polarized orbitals and they are close to the phase shifts calculated earlier by Bhatia [Phys. Rev. A10.1103/PhysRevA.69.032714 69, 032714 (2004)]. This indicates that the correlation function is general enough to include the target distortion (polarization) in the presence of the incident electron. The important fact is that in the present calculation, to obtain similar results only a 20-term correlation function is needed in the wave function compared to the 220-term wave function required in the above-mentioned calculation. Results for the phase shifts, obtained in the present hybrid formalism, are rigorous lower bounds to the exact phase shifts. The lowest P-wave resonances in He atom and hydrogen ion have also been calculated and compared with the results obtained using the Feshbach projection operator formalism [Bhatia and Temkin, Phys. Rev. A10.1103/PhysRevA.11.2018 11, 2018 (1975)] and also with the results of other calculations. It is concluded that accurate resonance parameters can be obtained by the present method, which has the advantage of including corrections due to neighboring resonances, bound states, and the continuum in which these resonances are embedded.

Locv Calculations for Polarized Liquid 3He with the Spin-Dependent Correlation

NASA Astrophysics Data System (ADS)

Bordbar, G. H.; Karimi, M. J.

We have used the lowest order constrained variational (LOCV) method to calculate some ground-state properties of polarized liquid 3 He at zero temperature with the spin-dependent correlation function employing the Lennard-Jones and Aziz pair potentials. We have seen that the total energy of polarized liquid 3He increases with increasing polarization. For all polarizations, it is shown that the total energy in the spin-dependent case is lower than the spin-independent case. We have seen that the difference between the energies of spin-dependent and spin-independent cases decreases by increasing the polarization. We have shown that the main contribution of the potential energy comes from the spin-triplet state.

Magnetic coupling between liquid 3He and a solid state substrate: a new approach

NASA Astrophysics Data System (ADS)

Klochkov, Alexander V.; Naletov, Vladimir V.; Tayurskii, Dmitrii A.; Tagirov, Murat S.; Suzuki, Haruhiko

2000-07-01

We suggest a new approach for solving the long-standing problem of a magnetic coupling between liquid 3He and a solid state substrate at temperatures above the Fermi temperature. The approach is based on our previous careful investigations of the physical state of a solid substrate by means of several experimental methods (EPR, NMR, conductometry, and magnetization measurements). The developed approach allows, first, to get more detailed information about the magnetic coupling phenomenon by varying the repetition time in pulse NMR investigations of liquid 3He in contact with the solid state substrate and, second, to compare the obtained dependences and the data of NMR-cryoporometry and AFM-microscopy.

Rotational relaxation of fluoromethane molecules in low-temperature collisions with buffer-gas helium

NASA Astrophysics Data System (ADS)

Li, Xingjia; Xu, Liang; Yin, Yanning; Xu, Supeng; Xia, Yong; Yin, Jianping

2016-06-01

We propose a method to study the rotational relaxation of polar molecules [here taking fluoromethane (CH3F ) as an example] in collisions with 3.5 K buffer-gas helium (He) atoms by using an electrostatic guiding technique. The dependence of the guiding signal of CH3F on the injected He flux and the dependence of the guiding efficiency of CH3F on its rotational temperature are investigated both theoretically and experimentally. By comparing the experimental and simulated results, we find that the translational and rotational temperatures of the buffer-gas cooled CH3F molecules can reach to about 5.48 and 0.60 K, respectively, and the ratio between the translational and average rotational collisional cross sections of CH3F -He is γ =σt/σr=36.49 ±6.15 . In addition, the slowing, cooling, and boosting effects of the molecular beam with different injected He fluxes are also observed and their forming conditions are investigated in some detail. Our study shows that our proposed method can not only be used to measure the translational and rotational temperatures of the buffer-gas cooled molecules, but also to measure the ratio of the translational collisional cross section to the average rotational collisional cross section, and even to measure the average rotational collisional cross section when the translational collisional cross section is measured by fitting the lifetime of molecule signal to get a numerical solution from the diffusion equation of buffer-gas He atoms in the cell.

Diagnosis of BK viral nephropathy in the renal allograft biopsy: role of fluorescence in situ hybridization.

PubMed

Wang, Zhen; Portier, Bryce P; Hu, Bo; Chiesa-Vottero, Andres; Myles, Jonathan; Procop, Gary W; Tubbs, Raymond R

2012-09-01

Early recognition of BK viral nephropathy is essential for successful management. Our aim in this study was to evaluate a novel fluorescence in situ hybridization (FISH) assay for detection of BK virus in renal transplant biopsies in the context of standard detection methods. Renal allograft biopsies (n = 108) were analyzed via H&E, immunohistochemistry (IHC) for simian virus 40, and FISH for BK virus. BK virus was detected in 16 (14.8%) cases by H&E, 13 (12%) cases by IHC, 18 (16.6%) cases by FISH, and 19 (17.6%) cases by real-time PCR; 24 of 108 showed a discrepancy in ≥1 testing modalities. Comparison of H&E, IHC, and FISH showed no statistical difference in detection of BK virus. However, performing comparisons between the different tissue-based assays in the context of plasma or urine real-time PCR results showed significant improvement in detection of BK by FISH over H&E (P = 0.02) but not IHC (P = 0.07). This novel FISH-based approach for BK virus identification in renal allograft biopsy tissue mirrored real-time PCR results and showed superior performance to detection of inclusions by H&E. Therefore, use of FISH for BK virus detection in the setting of renal allograft biopsy is a useful and sensitive detection method and could be adopted in any laboratory that currently performs FISH analysis. Copyright © 2012 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

Thomas Willis, a pioneer in translational research in anatomy (on the 350th anniversary of Cerebri anatome)

PubMed Central

Arráez-Aybar, Luis-Alfonso; Navia-Álvarez, Pedro; Fuentes-Redondo, Talia; Bueno-López, José-L

2015-01-01

The year 2014 marked the 350th anniversary of the publication in London of Cerebri anatome, a ground-breaking work of neuroscience heavily influenced by the political and cultural context of Baroque Europe and mid-17th century England. This article aims to review the work of the English physician and anatomist Thomas Willis, specifically with regard to the contents of his Cerebri anatome. Willis's academic and professional career was influenced by the turbulent period of the English Civil War during which he studied medicine. Willis went from chemistry to dissection arguably because of his need to justify the body-brain-soul relationship. As a result, he became a fellow of a select club of eminent experimentalists, and afterward was a Fellow of the Royal Society. Later on, he went to London, leaving the academic life to dedicate himself fully to the profession of medicine. As a physician, Willis did not base his practice on aphorisms but on a ‘bench to bedside’ approach to medicine, while studying neuroanatomy – covering embryology, comparative anatomy and pathological anatomy – as a basis for the comprehension of neurological pathology. He developed innovative anatomical methods for the preservation and dissection of the brain, injection of coloured substances and illustration of his findings. In Cerebri anatome, Willis recognized the cerebral cortex as the substrate of cognition. He also claimed that the painful stimuli came from the meninges, but not from the brain itself. He explained for the first time the pathological and functional meaning of the brain's circular arterial anastomosis, which is named after him. He also specified some features of the cranial origin of the sympathetic nerves and coined the term ‘neurologie’. Cerebri anatome marked the transition between the mediaeval and modern notions of brain function, and thus it is considered a cornerstone of clinical and comparative anatomy of the nervous system. The new contributions and methods employed by Willis justify his place as a father of neurology and a pioneer of translational research. PMID:25688933

Monodispersed calcium carbonate nanoparticles modulate local pH and inhibit tumor growth in vivo

NASA Astrophysics Data System (ADS)

Som, Avik; Raliya, Ramesh; Tian, Limei; Akers, Walter; Ippolito, Joseph E.; Singamaneni, Srikanth; Biswas, Pratim; Achilefu, Samuel

2016-06-01

The acidic extracellular environment of tumors potentiates their aggressiveness and metastasis, but few methods exist to selectively modulate the extracellular pH (pHe) environment of tumors. Transient flushing of biological systems with alkaline fluids or proton pump inhibitors is impractical and nonselective. Here we report a nanoparticles-based strategy to intentionally modulate the pHe in tumors. Biochemical simulations indicate that the dissolution of calcium carbonate nanoparticles (nano-CaCO3) in vivo increases pH asymptotically to 7.4. We developed two independent facile methods to synthesize monodisperse non-doped vaterite nano-CaCO3 with distinct size range between 20 and 300 nm. Using murine models of cancer, we demonstrate that the selective accumulation of nano-CaCO3 in tumors increases tumor pH over time. The associated induction of tumor growth stasis is putatively interpreted as a pHe increase. This study establishes an approach to prepare nano-CaCO3 over a wide particle size range, a formulation that stabilizes the nanomaterials in aqueous solutions, and a pH-sensitive nano-platform capable of modulating the acidic environment of cancer for potential therapeutic benefits.The acidic extracellular environment of tumors potentiates their aggressiveness and metastasis, but few methods exist to selectively modulate the extracellular pH (pHe) environment of tumors. Transient flushing of biological systems with alkaline fluids or proton pump inhibitors is impractical and nonselective. Here we report a nanoparticles-based strategy to intentionally modulate the pHe in tumors. Biochemical simulations indicate that the dissolution of calcium carbonate nanoparticles (nano-CaCO3) in vivo increases pH asymptotically to 7.4. We developed two independent facile methods to synthesize monodisperse non-doped vaterite nano-CaCO3 with distinct size range between 20 and 300 nm. Using murine models of cancer, we demonstrate that the selective accumulation of nano-CaCO3 in tumors increases tumor pH over time. The associated induction of tumor growth stasis is putatively interpreted as a pHe increase. This study establishes an approach to prepare nano-CaCO3 over a wide particle size range, a formulation that stabilizes the nanomaterials in aqueous solutions, and a pH-sensitive nano-platform capable of modulating the acidic environment of cancer for potential therapeutic benefits. Electronic supplementary information (ESI) available: Summary of experiments, theoretical schema of effect, synthesis schema, X-Ray diffraction results, TEM of effects of different solvents on particles in various solvents. See DOI: 10.1039/c5nr06162h

M-CSF in a new biomarker panel with HE4 and CA 125 in the diagnostics of epithelial ovarian cancer patients.

PubMed

Będkowska, Grażyna Ewa; Ławicki, Sławomir; Gacuta, Ewa; Pawłowski, Przemysław; Szmitkowski, Maciej

2015-05-03

We investigated plasma levels of M-CSF and conventional tumor markers (HE4 and CA 125) in epithelial ovarian cancer patients as compared to control groups: benign ovarian tumor patients (cysts) and healthy subjects. M-CSF levels were determined by ELISA, HE4 and CA 125 levels - by CMIA method. Our results have demonstrated significant differences in the concentration levels of M-CSF, CA 125 and HE4 between the groups of ovarian cancer patients, cysts patients and the healthy controls. In the groups tested M-CSF demonstrated equal to or higher values than both CA 125 and HE4 in diagnostic sensitivity (SE), positive and negative predictive values (PPV, NPV), and in the area under the ROC curve (AUC), particularly in the group with the serous epithelial sub-type of OC. Moreover, CA 125 showed better results of the aforementioned diagnostic criteria than HE4. The combined use of the parameters studied resulted in a further, significant increase in the value of the diagnostic indicators and in the value of the diagnostic power (AUC), especially in the early stages of ovarian cancer. These findings suggest a high usefulness of M-CSF in diagnosing the serous sub-type of epithelial ovarian cancer and in discriminating between cancer and non-carcinoma lesions, particularly in new diagnostic panels in combination with CA 125 and HE4 for the detection of EOC in the early stages.

The critical role of quercetin in autophagy and apoptosis in HeLa cells.

PubMed

Wang, Yijun; Zhang, Wei; Lv, Qiongying; Zhang, Juan; Zhu, Dingjun

2016-01-01

In recent years, the effects of quercetin on autophagy and apoptosis of cancer cells have been widely reported, while effects on HeLa cells are still unclear. Here, HeLa cells were subjected to quercetin treatment, and then proliferation, apoptosis, and autophagy were evaluated using MTT, flow cytometry, and MDC staining, respectively. The LC3-I/II, Beclin 1, active caspase-3, and S6K1 phosphorylation were detected using Western blot assay. The ultrastructure of HeLa was observed via transmission electron microscope (TEM). Our findings showed that quercetin can dose-dependently inhibit the growth of HeLa cells. The MDC fluorescence was enhanced with increased concentration of quercetin and hit a plateau at 50 μmol/l. Western blot assay revealed that LC3-I/II ratio, Beclin 1, and active caspase-3 protein were enforced in a dose-dependent method. However, the phosphorylation of S6K1 gradually decreased, concomitant with an increase of autophagy. In addition, TEM revealed that the number of autophagic vacuoles was peaked at 50 μmol/l of quercetin. Besides, interference of autophagy with 3-MA led to proliferation inhibition and increased apoptosis in HeLa cells, accompanied by the decreased LC3-I/II conversion and the increased active caspase-3. In conclusion, quercetin can inhibit HeLa cell proliferation and induce protective autophagy at low concentrations; thus, 3-MA plus quercetin would suppress autophagy and effectively increased apoptosis.

Marshall Barber and the century of microinjection: from cloning of bacteria to cloning of everything.

PubMed

Korzh, Vladimir; Strähle, Uwe

2002-08-01

A hundred years ago, Dr. Marshall A. Barber proposed a new technique - the microinjection technique. He developed this method initially to clone bacteria and to confirm the germ theory of Koch and Pasteur. Later on, he refined his approach and was able to manipulate nuclei in protozoa and to implant bacteria into plant cells. Continuous improvement and adaptation of this method to new applications dramatically changed experimental embryology and cytology and led to the formation of several new scientific disciplines including animal cloning as one of its latest applications. Interestingly, microinjection originated as a method at the crossroad of bacteriology and plant biology, demonstrating once again the unforeseen impact that basic research in an unrelated field can have on the development of entirely different disciplines.

Quality assurance and risk management: Perspectives on Human Factors Certification of Advanced Aviation Systems

NASA Technical Reports Server (NTRS)

Taylor, Robert M.; Macleod, Iain S.

1994-01-01

This paper is based on the experience of engineering psychologists advising the U.K. Ministry of Defense (MoD) on the procurement of advanced aviation systems that conform to good human engineering (HE) practice. Traditional approaches to HE in systems procurement focus on the physical nature of the human-machine interface. Advanced aviation systems present increasingly complex design requirements for human functional integration, information processing, and cognitive task performance effectiveness. These developing requirements present new challenges for HE quality assurance (QA) and risk management, requiring focus on design processes as well as on design content or product. A new approach to the application of HE, recently adopted by NATO, provides more systematic ordering and control of HE processes and activities to meet the challenges of advanced aircrew systems design. This systematic approach to HE has been applied by MoD to the procurement of mission systems for the Royal Navy Merlin helicopter. In MoD procurement, certification is a judicial function, essentially independent of the service customer and industry contractor. Certification decisions are based on advice from MoD's appointed Acceptance Agency. Test and evaluation (T&E) conducted by the contractor and by the Acceptance Agency provide evidence for certification. Certification identifies limitations of systems upon release to the service. Evidence of compliance with HE standards traditionally forms the main basis of HE certification and significant non-compliance could restrict release. The systems HE approach shows concern for the quality of processes as well as for the content of the product. Human factors certification should be concerned with the quality of HE processes as well as products. Certification should require proof of process as well as proof of content and performance. QA criteria such as completeness, consistency, timeliness, and compatibility provide generic guidelines for progressive acceptance and certification of HE processes. Threats to the validity of certification arise from problems and assumptions in T&E methods. T&E should seek to reduce the risk of specification non-compliance and certification failure.

Tactical Decision Making under Categorical Uncertainty with Applications to Modeling and Simulation

DTIC Science & Technology

2008-12-01

Method, Rene Descartes (1637) addressed the importance of discovery and truth through science. To accomplish this, he asked man to “reject all...previous knowledge, opinion, and customs” ( Descartes , 1637, p. 21). He writes: The first was never to accept anything as true which I did not clearly know...and distinctly as to exclude all possibility of doubt. Descartes was arguing two points. First, knowledge, and therefore truth, cannot, and must

Diagnosis-Prescription in the Context of Instructional Management

ERIC Educational Resources Information Center

Besel, Ronald

1973-01-01

Author argues that individual assessment of the students learning style should precede the decision of which teaching method is appropriate. He applies the medical terminology of diagnosis-prescription to this method of instructional development for management. (HB)

Lamb Shift Measurement in Hydrogen by the Anisotropy Method

NASA Astrophysics Data System (ADS)

Drake, G. W. F.; van Wijngaarden, A.; Holuj, F.

1998-05-01

The Lamb shift in hydrogen and hydrogenic ions continues to provide one of the most important tests of quantum electrodynamics. A previous measurement in He^+ by the anisotropy method( A. van Wijngaarden, J. Kwela and G. W. F. Drake, Phys. Rev. A 43), 3325 (1991). yields a value that is 70(12) parts per million higher than theory when two-loop binding corrections are included (K. Pachucki et al.), J. Phys. B 29, 117 (1996).. A new high-precision measurement of the Lamb shift in hydrogen by the same method will be reported( Can. J. Phys. 76), February (1998).. The result of 1057.852(15) MHz is consistent with theory and other measurements, thereby confirming that the anisotropy method and its interpretation are valid at the 15 parts per million level of accuracy. The remaining discrepancy for He^+ could be explained by an additional contribution to theory that scales as Z^6.

32 CFR 1615.1 - Registration.

Code of Federal Regulations, 2010 CFR

2010-07-01

... registration card or other method of registration prescribed by the Director of Selective Service by a person... method of registration prescribed by the Director, he shall advise in writing the Selective Service System, P.O. Box 94638, Palatine, IL 60094-4638. (c) The methods of registration prescribed by the...

Analysis of hemoglobin electrophoresis results and physicians investigative practices in Saudi Arabia

PubMed Central

Mehdi, Syed Riaz; Al Dahmash, Badr Abdullah

2013-01-01

BACKGROUND AND OBJECTIVES: Riyadh and central province falls in a moderate prevalent zone of hemoglobinopathies in Saudi Arabia. However, it has been observed that the physicians working in Saudi Arabia invariably advise all cases of anemia for hemoglobin electrophoresis (HE). The present work was carried out to study the yield of the HE in Riyadh and the investigative practices of the physicians advising HE. SETTINGS AND DESIGN: The study was carried out in the hospitals of King Saud University from 2009 to 2011 in order to assess the yield of HE in referred cases of clinical anemia. MATERIALS AND METHODS: A total of 1073 cases divided in two groups of males and females had undergone complete blood count and red blood cell morphology. Cellulose acetate HE was performed and all the positive results were reconfirmed on the high performance liquid chromatography (HPLC). The results were analyzed for the type of hemoglobinopathies. For statistical analysis Statistical Package for Social Sciences 15 version (SPSS Inc., Chicago, IL, USA) was used. RESULTS: A total of 405 males and 668 females blood samples were included in the present study. 116 (28.5%) males and 167 (25%) females showed an abnormal pattern on HE. The incidence of beta thalassemia trait was higher in females while sickle cell trait was predominantly seen in males. Red cell indices were reduced considerably in thalassemias, but were unaffected in sickle cell disorders, except those which had concurrent alpha trait. The total yield of HE was 26.6% which was much less than expected. CONCLUSION: The physicians are advised to rule out iron deficiency and other common causes of anemia before investigating the cases for hemoglobinopathies, which employs time consuming and expensive tests of HE and HPLC. PMID:24339548

Active galactic nuclei from He II: a more complete census of AGN in SDSS galaxies yields a new population of low-luminosity AGN in highly star-forming galaxies

NASA Astrophysics Data System (ADS)

Bär, Rudolf E.; Weigel, Anna K.; Sartori, Lia F.; Oh, Kyuseok; Koss, Michael; Schawinski, Kevin

2017-04-01

In order to perform a more complete census of active galactic nuclei (AGN) in the local Universe, we investigate the use of the He II λ4685 emission line diagnostic diagram by Shirazi & Brinchmann (2012) in addition to the standard methods based on other optical emission lines. The He II-based diagnostics is more sensitive to AGN ionization in the presence of strong star formation than conventional line diagnostics. We survey a magnitude-limited sample of 63 915 galaxies from the Sloan Digital Sky Survey Data Release 7 at 0.02 < z < 0.05 and use both the conventional BPT emission line diagnostic diagrams, as well as the He II diagram to identify AGN. In this sample, 1075 galaxies are selected as AGN using the BPT diagram, while additional 234 galaxies are identified as AGN using the He II diagnostic diagram, representing a 22 per cent increase of AGN in the parent galaxy sample. We explore the host galaxy properties of these new He II-selected AGN candidates and find that they are most common in star-forming galaxies on the blue cloud and on the main sequence where ionization from star formation is most likely to mask AGN emission in the BPT lines. We note in particular a high He II AGN fraction in galaxies above the high-mass end of the main sequence where quenching is expected to occur. We use archival Chandra observations to confirm the AGN nature of candidates selected through He II-based diagnostic. Finally, we discuss how this technique can help inform galaxy/black hole coevolution scenarios.

Redox Pioneer: Professor Helmut Sies

PubMed Central

Radi, Rafael

2014-01-01

Abstract Professor Helmut Sies Dr. Helmut Sies (MD, 1967) is recognized as a Redox Pioneer, because he authored five articles on oxidative stress, lycopene, and glutathione, each of which has been cited more than 1000 times, and coauthored an article on hydroperoxide metabolism in mammalian systems cited more than 5000 times (Google Scholar). He obtained preclinical education at the University of Tübingen and the University of Munich, clinical training at Munich (MD, 1967) and Paris, and completed Habilitation at Munich (Physiological Chemistry and Physical Biochemistry, 1972). In early research, he first identified hydrogen peroxide (H2O2) as a normal aerobic metabolite and devised a method to quantify H2O2 concentration and turnover in cells. He quantified central redox systems for energy metabolism (NAD, NADP systems) and antioxidant GSH in subcellular compartments. He first described ebselen, a selenoorganic compound, as a glutathione peroxidase mimic. He contributed a fundamental discovery to the physiology of GSH, selenium nutrition, singlet oxygen biochemistry, and health benefits of dietary lycopene and cocoa flavonoids. He has published more than 600 articles, 134 of which are cited at least 100 times, and edited 28 books. His h-index is 115. During the last quarter of the 20th century and well into the 21st, he has served as a scout, trailblazer, and pioneer in redox biology. His formulation of the concept of oxidative stress stimulated and guided research in oxidants and antioxidants; his pioneering research on carotenoids and flavonoids informed nutritional strategies against cancer, cardiovascular disease, and aging; and his quantitative approach to redox biochemistry provides a foundation for modern redox systems biology. Helmut Sies is a true Redox Pioneer. Antioxid. Redox Signal. 21, 2459–2468. The joy of exploring the unknown and finding something novel and noteworthy: what a privilege! —Prof. Helmut Sies PMID:25178739

Post-Hartree-Fock studies of the He/Mg(0001) interaction: Anti-corrugation, screening, and pairwise additivity

NASA Astrophysics Data System (ADS)

de Lara-Castells, María Pilar; Fernández-Perea, Ricardo; Madzharova, Fani; Voloshina, Elena

2016-06-01

The adsorption of noble gases on metallic surfaces represents a paradigmatic case of van-der-Waals (vdW) interaction due to the role of screening effects on the corrugation of the interaction potential [J. L. F. Da Silva et al., Phys. Rev. Lett. 90, 066104 (2003)]. The extremely small adsorption energy of He atoms on the Mg(0001) surface (below 3 meV) and the delocalized nature and mobility of the surface electrons make the He/Mg(0001) system particularly challenging, even for state-of-the-art vdW-corrected density functional-based (vdW-DFT) approaches [M. P. de Lara-Castells et al., J. Chem. Phys. 143, 194701 (2015)]. In this work, we meet this challenge by applying two different procedures. First, the dispersion-corrected second-order Möller-Plesset perturbation theory (MP2C) approach is adopted, using bare metal clusters of increasing size. Second, the method of increments [H. Stoll, J. Chem. Phys. 97, 8449 (1992)] is applied at coupled cluster singles and doubles and perturbative triples level, using embedded cluster models of the metal surface. Both approaches provide clear evidences of the anti-corrugation of the interaction potential: the He atom prefers on-top sites, instead of the expected hollow sites. This is interpreted as a signature of the screening of the He atom by the metal for the on-top configuration. The strong screening in the metal is clearly reflected in the relative contribution of successively deeper surface layers to the main dispersion contribution. Aimed to assist future dynamical simulations, a pairwise potential model for the He/surface interaction as a sum of effective He-Mg pair potentials is also presented, as an improvement of the approximation using isolated He-Mg pairs.

Applications of the gambling score in evaluating earthquake predictions and forecasts

NASA Astrophysics Data System (ADS)

Zhuang, Jiancang; Zechar, Jeremy D.; Jiang, Changsheng; Console, Rodolfo; Murru, Maura; Falcone, Giuseppe

2010-05-01

This study presents a new method, namely the gambling score, for scoring the performance earthquake forecasts or predictions. Unlike most other scoring procedures that require a regular scheme of forecast and treat each earthquake equally, regardless their magnitude, this new scoring method compensates the risk that the forecaster has taken. Starting with a certain number of reputation points, once a forecaster makes a prediction or forecast, he is assumed to have betted some points of his reputation. The reference model, which plays the role of the house, determines how many reputation points the forecaster can gain if he succeeds, according to a fair rule, and also takes away the reputation points bet by the forecaster if he loses. This method is also extended to the continuous case of point process models, where the reputation points betted by the forecaster become a continuous mass on the space-time-magnitude range of interest. For discrete predictions, we apply this method to evaluate performance of Shebalin's predictions made by using the Reverse Tracing of Precursors (RTP) algorithm and of the outputs of the predictions from the Annual Consultation Meeting on Earthquake Tendency held by China Earthquake Administration. For the continuous case, we use it to compare the probability forecasts of seismicity in the Abruzzo region before and after the L'aquila earthquake based on the ETAS model and the PPE model.

Constraining Galactic cosmic-ray parameters with Z ≤ 2 nuclei

NASA Astrophysics Data System (ADS)

Coste, B.; Derome, L.; Maurin, D.; Putze, A.

2012-03-01

Context. The secondary-to-primary B/C ratio is widely used for studying Galactic cosmic-ray propagation processes. The 2H/4He and 3He/4He ratios probe a different Z/A regime, which provides a test for the "universality" of propagation. Aims: We revisit the constraints on diffusion-model parameters set by the quartet (1H, 2H, 3He, 4He), using the most recent data as well as updated formulae for the inelastic and production cross-sections. Methods: Our analysis relies on the USINE propagation package and a Markov Chain Monte Carlo technique to estimate the probability density functions of the parameters. Simulated data were also used to validate analysis strategies. Results: The fragmentation of CNO cosmic rays (resp. NeMgSiFe) on the interstellar medium during their propagation contributes to 20% (resp. 20%) of the 2H and 15% (resp. 10%) of the 3He flux at high energy. The C to Fe elements are also responsible for up to 10% of the 4He flux measured at 1 GeV/n. The analysis of 3He/4He (and to a lesser extent 2H/4He) data shows that the transport parameters are consistent with those from the B/C analysis: the diffusion model with δ ~ 0.7 (diffusion slope), Vc ~ 20 km s-1 (galactic wind), Va ~ 40 km s-1 (reacceleration) is favoured, but the combination δ ~ 0.2, Vc ~ 0, and Va ~ 80 km s-1 is a close second. The confidence intervals on the parameters show that the constraints set by the quartet data can compete with those derived from the B/C data. These constraints are tighter when adding the 3He (or 2H) flux measurements, and the tightest when the He flux is added as well. For the latter, the analysis of simulated and real data shows an increased sensitivity to biases. Using the secondary-to-primary ratio along with a loose prior on the source parameters is recommended to obtain the most robust constraints on the transport parameters. Conclusions: Light nuclei should be systematically considered in the analysis of transport parameters. They provide independent constraints that can compete with those obtained from the B/C analysis.

26 CFR 1.77-1 - Election to consider Commodity Credit Corporation loans as income.

Code of Federal Regulations, 2010 CFR

2010-04-01

... Commodity Credit Corporation, unless he secures the permission of the Commissioner to change to a different method of accounting. Application for permission to change such method of accounting and the basis upon...

Testing Standard Reliability Criteria

ERIC Educational Resources Information Center

Sherry, David

2017-01-01

Maul's paper, "Rethinking Traditional Methods of Survey Validation" (Andrew Maul), contains two stages. First he presents empirical results that cast doubt on traditional methods for validating psychological measurement instruments. These results motivate the second stage, a critique of current conceptions of psychological measurement…

Remembering Larkin

NASA Astrophysics Data System (ADS)

Varlamov, Andrei

2013-06-01

Knowing Anatoly Ivanovich - Tolya for his friends and colleagues - for years I can't recall him ever writing mathematical expressions on a sheet of paper as he was usually solving problems in his head. Tolya was Homo Sapiens in its true, literal sense of this word. A side observer would hardly notice his mastery and deep understanding of modern methods of theoretical physics and mathematics as there were no piles of paper speckled with math symbols on his desk. But there was a blackboard in his office, all covered with fragments of problems he was discussing with various coauthors. He was famous among his students and coauthors for "falling asleep" in the chair in his office and then writing the solution on the board immediately after awakening...

The Breivik case and what psychiatrists can learn from it

PubMed Central

Melle, Ingrid

2013-01-01

In the afternoon of July 22, 2011, Norwegian Anders Behring Breivik killed 77 persons, many of them children and youths, in two separate events. On August 24, 2012, he was sentenced to 21 years in prison. Breivik went through two forensic evaluations: the first concluded that he had a psychotic disorder, thus being legally unaccountable, whereas the second concluded that he had a personality disorder, thus being legally accountable. This article first describes Breivik's background and his crimes. This is followed by an overview of the two forensic evaluations, their methods, contents and disagreements, and how these issues were handled by the court in the verdict. Finally, the article focuses on some lessons psychiatrists can take from the case. PMID:23471788

The Breivik case and what psychiatrists can learn from it.

PubMed

Melle, Ingrid

2013-02-01

In the afternoon of July 22, 2011, Norwegian Anders Behring Breivik killed 77 persons, many of them children and youths, in two separate events. On August 24, 2012, he was sentenced to 21 years in prison. Breivik went through two forensic evaluations: the first concluded that he had a psychotic disorder, thus being legally unaccountable, whereas the second concluded that he had a personality disorder, thus being legally accountable. This article first describes Breivik's background and his crimes. This is followed by an overview of the two forensic evaluations, their methods, contents and disagreements, and how these issues were handled by the court in the verdict. Finally, the article focuses on some lessons psychiatrists can take from the case. Copyright © 2013 World Psychiatric Association.

Infection of nonphagocytic host cells by legionella.

PubMed

Day, Shandra R; Sifri, Costi D; Hoffman, Paul S

2013-01-01

Legionella pneumophila is an intracellular pathogen of free-living protozoa that can also infect alveolar macrophages, L929 fibroblast cells, and HeLa cells. Infection of nonphagocytic cells by L. pneumophila can be used to study invasion mechanisms, compare infectivity of different strains and identify factors important for virulence. Virulent strains of L. pneumophila exposed to monolayers of L929 cells are able to invade and form virus-like plaques, which can be enumerated as a measure of infectivity. Invasiveness of HeLa cells can also be used to evaluate relative infectivity and to study mechanisms of invasion and to track the development of cyst-like forms. The detailed methods of both the L929 plaque assay and HeLa cell invasion assay are described.

Analysis of a space debris laser removal system

NASA Astrophysics Data System (ADS)

Gjesvold, Evan; Straub, Jeremy

2017-05-01

As long as man ventures into space, he will leave behind debris, and as long as he ventures into space, this debris will pose a threat to him and his projects. Space debris must be located and decommissioned. Lasers may prove to be the ideal method, as they can operate at a distance from the debris, have a theoretically infinite supply of energy from the sun, and are a seemingly readily available technology. This paper explores the requirements and reasoning for such a laser debris removal method. A case is made for the negligibility of eliminating rotational velocity from certain systems, while a design schematic is also presented for the implementation of a cube satellite proof of concept.

Trinitrotoluene Induces Endoplasmic Reticulum Stress and Apoptosis in HePG2 Cells

PubMed Central

Song, Li; Wang, Yue; Wang, Jun; Yang, Fan; Li, Xiaojun; Wu, Yonghui

2015-01-01

Background This study aims to describe trinitrotoluene (TNT)-induced endoplasmic reticulum stress (ERS) and apoptosis in HePG2 cells. Material/Methods HePG2 cells were cultured in vitro with 0, 6, 12, or 24 μg/ml TNT solution for 12, 24, and 48 h. Western blotting was performed to detect intracellular ERS-related proteins, including glucose-regulated protein (GRP) 78, GRP94, Caspase 4, p-Jun N-terminal kinase (JNK), and C/EBP homologous protein (CHOP). Real-time PCR was used to measure mRNA expression from the respective genes. Results The expressions of ERS-related proteins GRP78 and GRP94 as well as mRNA and protein expression of ERS signaling apoptotic CHOP in the TNT treatment group were significantly increased. In addition, the mRNA and protein expression levels of ERS-induced apoptotic protein Caspase-4 were significantly increased. Flow cytometry revealed that after TNT treatment, the apoptosis rate also significantly increased. Conclusions TNT could increase the expression levels of GRP78, GRP94, Caspase-4, and CHOP in HePG2 cells; this increase in protein expression might be involved in HePG2 apoptosis through the induction of the ERS pathway. PMID:26551326

Charge Transfer Processes in Collisions of Si4+ Ions with He Atoms at Intermediate Energies

NASA Astrophysics Data System (ADS)

Suzuki, R.; Watanabe, A.; Sato, H.; Gu, J. P.; Hirsch, G.; Buenker, R. J.; Kimura, M.; Stancil, P. C.

Charge transfer in collisions of Si4+ ions with He atoms below 100 keV/u is studied by using a molecular orbital representation within both the semiclassical and quantal representations. Single transfer reaction Si4++He →Si3++He+ has been studied by a number of theoretical investigations. In addition to the reaction (1), the first semiclassical MOCC calculations are performed for the double transfer channel Si4++HE→Si2++He2+ Nine molecular states that connect both with single and double electron transfer processes are considered in the present model. Electronic states and corresponding couplings are determined by the multireference single- and double- excitation configuration interaction method. The present cross sections tie well with the earlier calculations of Stancil et al., Phys. Rev. A 55, 1064 (1997) at lower energies, but show a rather different magnitude from those of Bacchus-Montabonel and Ceyzeriat, Phys. Rev. A 58, 1162 (1998). The present rate constant is found to be significantly different from the experimental finding of Fang and Kwong, Phys. Rev. A 59, 342 (1996) at 4,600 K, and hence does not support the experiment.

Taking Measure of the Universe: How Big? How Old? How Do We Know?

NASA Astrophysics Data System (ADS)

Kirshner, Robert

1997-11-01

Supernovae, exploding stars that shine as brightly as a billion Suns, areastonishing events which offer the best method for measuring the size andshape of the universe. Professor Kirshner explains how stars explodeand how astronomers piece together clues from these brilliant disastersto understand the age, shape, and fate of the Universe. Click here for more info.Robert P. Kirshner is Professor of Astronomy at Harvard University,where he chaired the department from 1990 to 1997. In Fall 1997 he was onsabbatical at the Institute for Theoretical Physics at the University ofCalifornia, Santa Barbara.Kirshner's scientific work has centered on supernova explosions andtheir application to measuring t he Universe. The author of over 150scientific publications, Kirshner is Principal Investigator for SINS, theSupernova Intensive Study with the Hubble Space Telescope. He is a memberof the American Academy of Arts and Sciences.At Harvard, Kirshner teaches a large core curriculum coursecalled Matter in the Universe. Dubbed "the David Letterman of astronomy"by his colleagues for his entertaining lecture manner, he has writtenpopular articles for National Geographic, ScientificAmerican, Natural History, Sky and Telescope, and theWorld Book Encyclopedia.

Microvessel prediction in H&E Stained Pathology Images using fully convolutional neural networks.

PubMed

Yi, Faliu; Yang, Lin; Wang, Shidan; Guo, Lei; Huang, Chenglong; Xie, Yang; Xiao, Guanghua

2018-02-27

Pathological angiogenesis has been identified in many malignancies as a potential prognostic factor and target for therapy. In most cases, angiogenic analysis is based on the measurement of microvessel density (MVD) detected by immunostaining of CD31 or CD34. However, most retrievable public data is generally composed of Hematoxylin and Eosin (H&E)-stained pathology images, for which is difficult to get the corresponding immunohistochemistry images. The role of microvessels in H&E stained images has not been widely studied due to their complexity and heterogeneity. Furthermore, identifying microvessels manually for study is a labor-intensive task for pathologists, with high inter- and intra-observer variation. Therefore, it is important to develop automated microvessel-detection algorithms in H&E stained pathology images for clinical association analysis. In this paper, we propose a microvessel prediction method using fully convolutional neural networks. The feasibility of our proposed algorithm is demonstrated through experimental results on H&E stained images. Furthermore, the identified microvessel features were significantly associated with the patient clinical outcomes. This is the first study to develop an algorithm for automated microvessel detection in H&E stained pathology images.

Helmholtz and parabolic equation solutions to a benchmark problem in ocean acoustics.

PubMed

Larsson, Elisabeth; Abrahamsson, Leif

2003-05-01

The Helmholtz equation (HE) describes wave propagation in applications such as acoustics and electromagnetics. For realistic problems, solving the HE is often too expensive. Instead, approximations like the parabolic wave equation (PE) are used. For low-frequency shallow-water environments, one persistent problem is to assess the accuracy of the PE model. In this work, a recently developed HE solver that can handle a smoothly varying bathymetry, variable material properties, and layered materials, is used for an investigation of the errors in PE solutions. In the HE solver, a preconditioned Krylov subspace method is applied to the discretized equations. The preconditioner combines domain decomposition and fast transform techniques. A benchmark problem with upslope-downslope propagation over a penetrable lossy seamount is solved. The numerical experiments show that, for the same bathymetry, a soft and slow bottom gives very similar HE and PE solutions, whereas the PE model is far from accurate for a hard and fast bottom. A first attempt to estimate the error is made by computing the relative deviation from the energy balance for the PE solution. This measure gives an indication of the magnitude of the error, but cannot be used as a strict error bound.

Essay: In Memory of Robert Siemann

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

Chao, Alexander W.; /SLAC

Bob Siemann came to SLAC from Cornell in 1991. With the support from Burton Richter, then Director of SLAC, he took on a leadership role to formulate an academic program in accelerator physics at SLAC and the development of its accelerator faculty. Throughout his career he championed accelerator physics as an independent academic discipline, a vision that he fought so hard for and never retreated from. He convinced Stanford University and SLAC to create a line of tenured accelerator physics faculty and over the years he also regularly taught classes at Stanford and the U.S. Particle Accelerator School. After themore » shutdown of the SSC Laboratory, I returned to SLAC in 1993 to join the accelerator faculty he was forming. He had always visualized a need to have a professional academic journal for the accelerator field, and played a pivotal role in creating the journal Physical Review Special Topics - Accelerators and Beams, now the community standard for accelerator physics after nine years of his editorship. Today, Bob's legacy of accelerator physics as an independent academic discipline continues at SLAC as well as in the community, from which we all benefit. Bob was a great experimentalist. He specialized in experimental techniques and instrumentation, but what he wanted to learn is physics. If he had to learn theory - heaven forbid - to reach that goal, he would not hesitate one second to do so. In fact, he had written several theoretical papers as results of these efforts. Now this is what I call a true experimentalist! Ultimately, however, I think it was experimental instruments that he loved most. His eyes widened when he talked about his instruments. Prompted by a question, he would proceed to a nearby blackboard, with a satisfying grin, and draw his experimental device in a careful thinking manner, then describe his experiment and educate the questioner with some insightful physics. These moments were most enjoyable, to him and the questioner alike. When I think of Bob today, it is these moments that first come to mind, and it is these moments I will miss the most. I should like to mention another curious thing about Bob, namely he had a special talent of finding persuasive arguments that went his way. It was difficult to argue with Bob because it was so difficult to win. Generally quiet otherwise, he was too good and too methodical a debater. I had never seen him losing a debate on a policy issue or in a committee setting. However, when it comes to physics, his soft spot, he occasionally let go some weakness. When so doing, he would lose the debate, but his grin revealed that the loss was more than compensated by the physics he gained together with his debater. It is hard to believe that the office around the corner is now empty. The dear colleague we have come to know, to talk to, and to seek advice from, together with the feet-on-the-desk posture and the familiar grin, are no longer there. I wonder, who will now occupy that office next? And who will continue to carry on Bob Siemann's legacy? Many of us are waiting.« less

Translations on USSR Military Affairs, Number 1380

DTIC Science & Technology

1978-09-27

if it can be so said, to the emotional poverty of my relations with subordinates. He advised me to get closer to the men, and to better study their...his behaviour and actions. A convinced soldier embodies unity of ideas, feelings and will. He is characterised by stable principles, skills and...compulsion, which is an auxiliary method and is used with respect to service- men whose behaviour is at variance with the require- ments of the military

Designing Intelligent Computer Aided Instruction Systems with Integrated Knowledge Representation Schemes

DTIC Science & Technology

1990-06-01

the form of structured objects was first pioneered by Marvin Minsky . In his seminal article " A Framework for Representing Knowl- edge" he introduced... Minsky felt that the existing methods of knowledge representation were too finely grained and he proposed that knowledge is more than just a...not work" in realistic, complex domains. ( Minsky , 1981, pp. 95-128) According to Minsky "A frame is a data-structure for representing a stereo- typed

MiNDSTEp differential photometry of the gravitationally lensed quasars WFI 2033-4723 and HE 0047-1756: microlensing and a new time delay

NASA Astrophysics Data System (ADS)

Giannini, E.; Schmidt, R. W.; Wambsganss, J.; Alsubai, K.; Andersen, J. M.; Anguita, T.; Bozza, V.; Bramich, D. M.; Browne, P.; Calchi Novati, S.; Damerdji, Y.; Diehl, C.; Dodds, P.; Dominik, M.; Elyiv, A.; Fang, X.; Figuera Jaimes, R.; Finet, F.; Gerner, T.; Gu, S.; Hardis, S.; Harpsøe, K.; Hinse, T. C.; Hornstrup, A.; Hundertmark, M.; Jessen-Hansen, J.; Jørgensen, U. G.; Juncher, D.; Kains, N.; Kerins, E.; Korhonen, H.; Liebig, C.; Lund, M. N.; Lundkvist, M. S.; Maier, G.; Mancini, L.; Masi, G.; Mathiasen, M.; Penny, M.; Proft, S.; Rabus, M.; Rahvar, S.; Ricci, D.; Scarpetta, G.; Sahu, K.; Schäfer, S.; Schönebeck, F.; Skottfelt, J.; Snodgrass, C.; Southworth, J.; Surdej, J.; Tregloan-Reed, J.; Vilela, C.; Wertz, O.; Zimmer, F.

2017-01-01

Aims: We present V and R photometry of the gravitationally lensed quasars WFI 2033-4723 and HE 0047-1756. The data were taken by the MiNDSTEp collaboration with the 1.54 m Danish telescope at the ESO La Silla observatory from 2008 to 2012. Methods: Differential photometry has been carried out using the image subtraction method as implemented in the HOTPAnTS package, additionally using GALFIT for quasar photometry. Results: The quasar WFI 2033-4723 showed brightness variations of order 0.5 mag in V and R during the campaign. The two lensed components of quasar HE 0047-1756 varied by 0.2-0.3 mag within five years. We provide, for the first time, an estimate of the time delay of component B with respect to A of Δt = (7.6 ± 1.8) days for this object. We also find evidence for a secular evolution of the magnitude difference between components A and B in both filters, which we explain as due to a long-duration microlensing event. Finally we find that both quasars WFI 2033-4723 and HE 0047-1756 become bluer when brighter, which is consistent with previous studies. Based on data collected by MiNDSTEp with the Danish 1.54 m telescope at the ESO La Silla observatory.

In response to David Greenwood's `Place mobility and faculty life: mindfulness through change' through the lens of science teacher education programs

NASA Astrophysics Data System (ADS)

Nyaema, Mary K.

2017-06-01

In writing this review, I draw on the experience of David Greenwood (Cult Stud Sci Educ 10:5-16, 2015) whose ethnographic study sheds light on his growth as a faculty member who has taught in various settings that are quite different from the culture that he grew up with. I extend his thoughts on ecological mindfulness to encompass a culturally aware method of teaching based on place sensitized more to the needs of science teacher preparation programs. The methods used in writing the review included literature searches for articles that incorporate ecological mindfulness and culturally responsive teaching in science teacher preparation programs and reflected ideas voiced in Greenwood's article. Although he seems that he is primarily addressing other faculty members, his experiences can be used as lifelong lessons for preservice teachers entering a primarily homogeneous workforce expected to teach an increasingly diverse student population. His humor, use of Haiku, poetry and mindfulness as a way of becoming one with a culture that he is not accustomed has many lessons that prove useful in training more culturally responsive teachers. In light of an increasingly diverse US student population versus a stagnantly homogeneous teaching workforce, his reflective practice will prove useful to teachers who are expected to teach students with cultures different from their own.

Enhancing image contrast of carbon nanotubes on cellular background using helium ion microscope by varying helium ion fluence.

PubMed

Dykas, M M; Poddar, K; Yoong, S L; Viswanathan, V; Mathew, S; Patra, A; Saha, S; Pastorin, G; Venkatesan, T

2018-01-01

Carbon nanotubes (CNTs) have become an important nano entity for biomedical applications. Conventional methods of their imaging, often cannot be applied in biological samples due to an inadequate spatial resolution or poor contrast between the CNTs and the biological sample. Here we report a unique and effective detection method, which uses differences in conductivities of carbon nanotubes and HeLa cells. The technique involves the use of a helium ion microscope to image the sample with the surface charging artefacts created by the He + and neutralised by electron flood gun. This enables us to obtain a few nanometre resolution images of CNTs in HeLa Cells with high contrast, which was achieved by tailoring the He + fluence. Charging artefacts can be efficiently removed for conductive CNTs by a low amount of electrons, the fluence of which is not adequate to discharge the cell surface, resulting in high image contrast. Thus, this technique enables rapid detection of any conducting nano structures on insulating cellular background even in large fields of view and fine spatial resolution. The technique demonstrated has wider applications for researchers seeking enhanced contrast and high-resolution imaging of any conducting entity in a biological matrix - a commonly encountered issue of importance in drug delivery, tissue engineering and toxicological studies. © 2017 The Authors Journal of Microscopy © 2017 Royal Microscopical Society.

A method for calculating the gas volume proportions and inhalation temperature of inert gas mixtures allowing reaching normothermic or hypothermic target body temperature in the awake rat

PubMed Central

Abraini, Jacques H.; David, Hélène N.; Blatteau, Jean-Éric; Risso, Jean Jacques; Vallée, Nicolas

2017-01-01

The noble gases xenon (Xe) and helium (He) are known to possess neuroprotective properties. Xe is considered the golden standard neuroprotective gas. However, Xe has a higher molecular weight and lower thermal conductivity and specific heat than those of nitrogen, the main diluent of oxygen (O2) in air, conditions that could impair or at least reduce the intrinsic neuroprotective properties of Xe by increasing the critical care patient's respiratory workload and body temperature. In contrast, He has a lower molecular weight and higher thermal conductivity and specific heat than those of nitrogen, but is unfortunately far less potent than Xe at providing neuroprotection. Therefore, combining Xe with He could allow obtaining, depending on the gas inhalation temperature and composition, gas mixtures with neutral or hypothermic properties, the latter being advantageous in term of neuroprotection. However, calculating the thermal properties of a mixture, whatever the substances – gases, metals, rubbers, etc. – is not trivial. To answer this question, we provide a graphical method to assess the volume proportions of Xe, He and O2 that a gas mixture should contain, and the inhalation temperature to which it should be administered to allow a clinician to maintain the patient at a target body temperature. PMID:29152210

Publisher's Announcement

NASA Astrophysics Data System (ADS)

Scriven, Neil

2003-12-01

We are delighted to announce that the new Editor-in-Chief of Journal of Physics A: Mathematical and General for 2004 will be Professor Carl M Bender of Washington University, St. Louis. Carl will, with the help of his world class editorial board, maintain standards of scientific rigour whilst ensuring that research published is of the highest importance. Carl attained his first degree in physics at Cornell University before studying for his PhD at Harvard. He later worked at The Institute for Advanced Study in Princeton and at MIT before assuming his current position at Washington University, St Louis. He has been a visiting professor at Technion, Haifa, and Imperial College, London and a scientific consultant for Los Alamos National Laboratory. His main expertise is in using classical applied mathematics to solve a broad range of problems in high-energy theoretical physics and mathematical physics. Since the publication of his book Advanced Mathematical Methods for Scientists and Engineers, written with Steven Orszag, he has been regarded as an expert on the subject of asymptotic analysis and perturbative methods. `Carl publishes his own internationally-important research in the journal and has been an invaluable, energetic member of the Editorial Board for some time' said Professor Ed Corrigan, Carl's predecessor as Editor, `he will be an excellent Editor-in-Chief'. Our grateful thanks and best wishes go to Professor Corrigan who has done a magnificent job for the journal during his five-year tenure.

Evaluation of consolidation method on mechanical and structural properties of ODS RAF steel

NASA Astrophysics Data System (ADS)

Frelek-Kozak, M.; Kurpaska, L.; Wyszkowska, E.; Jagielski, J.; Jozwik, I.; Chmielewski, M.

2018-07-01

In the present work, the effects of the fabrication method on mechanical and structural properties of 12%Cr, 2%W, 0.25%Ti, 0.25%Y2O3 steels were investigated. Materials obtained by Spark Plasma Sintering (SPS), Hot Isostatic Pressing (HIP) and Hot Extrusion (HE) methods were studied. The microstructure was characterized by using Scanning Electron Microscopy (SEM) and Electron Backscatter Diffraction analysis (EBSD). Mechanical properties of the studied samples were evaluated by using Vickers micro hardness HV0.1, Small Punch Test (SPT) and nanoindentation (NI) methods. The analysis revealed that samples manufactured via HIP and SPS processes exhibit very similar properties, whereas SPS method produces material with slightly lower hardness. In addition, significantly lower mechanical properties of the specimens after HE process were observed. The study described in this article addresses also the problems of mechanical parameters measured in micro- and nano-scale experiments and aims to identify possible pitfalls related to the use of various manufacturing technologies.

In situ electrochemical assessment of cytotoxicity of chlorophenols in MCF-7 and HeLa cells.

PubMed

Qin, Hongwei; Liu, Jiguang; Zhang, Zeshi; Li, Jinlian; Gao, Guanggang; Yang, Yuxin; Yuan, Xing; Wu, Dongmei

2014-10-01

An in situ electrochemical method was used to assess the cytotoxicity of chlorophenols using human breast cancer (MCF-7) and cervical carcinoma (HeLa) cells as models. On treatment with different chlorophenols, the electrochemical responses of the selected cells, resulting from the oxidation of guanine and xanthine in the cytoplasm, indicated the cell viability. In addition, the in situ in vitro electrochemical method was further compared with the traditional MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assays. Although similar cytotoxicity data were obtained from both methods, the effective concentrations of chlorophenols that inhibited 50% cell growth (EC50 values) from the electrochemical method were only slightly lower than those from the MTT assay. These results indicate that the in situ in vitro electrochemical method paves a simple, rapid, strongly responsive, and label-free way to the cytotoxicity assessment of different chlorophenol pollutants. Copyright © 2014 Elsevier Inc. All rights reserved.

Fabrication of PDMS through-holes using the MIMIC method and the surface treatment by atmospheric-pressure CH4/He RF plasma

NASA Astrophysics Data System (ADS)

Choi, Jongchan; Lee, Kyeong-Hwan; Yang, Sung

2011-09-01

This note presents a simple fabrication process for patterning micro through-holes in a PDMS layer by a combination of the micromolding in capillaries (MIMIC) method and the surface treatment by atmospheric-pressure CH4/He RF plasma. The fabrication process is confirmed by forming micro through-holes with various shapes including circle, C-shape, open microfluidic channel and hemisphere. All micro through-holes of various shapes in a wide range of diameters and heights are well fabricated by the proposed method. Also, a 3D micromixer containing a PDMS micro through-hole layer formed by the proposed method is built and its performance is tested as another practical demonstration of the proposed fabrication method. Therefore, we believe that the proposed fabrication process will build a PDMS micro through-hole layer in a simple and easy way and will contribute to developing highly efficient multi-layered microfluidic systems, which may require PDMS micro through-hole layers.

Integral method for transient He II heat transfer in a semi-infinite domain

NASA Astrophysics Data System (ADS)

Baudouy, B.

2002-05-01

Integral methods are suited to solve a non-linear system of differential equations where the non-linearity can be found either in the differential equations or in the boundary conditions. Though they are approximate methods, they have proven to give simple solutions with acceptable accuracy for transient heat transfer in He II. Taking in account the temperature dependence of thermal properties, direct solutions are found without the need of adjusting a parameter. Previously, we have presented a solution for the clamped heat flux and in the present study this method is used to accommodate the clamped-temperature problem. In the case of constant thermal properties, this method yields results that are within a few percent of the exact solution for the heat flux at the axis origin. We applied this solution to analyze recovery from burnout and find an agreement within 10% at low heat flux, whereas at high heat flux the model deviates from the experimental data suggesting the need for a more refined thermal model.

[A new method for the classification of neonates based on maturity and somatic development].

PubMed

Berkö, P

1992-03-01

The author points out the sad fact that the methods of estimating classifying, comparative examining of the maturity, somatic development of newborns and the methods of marking off the retarded newborns used up to now are essentially centering round the birth-weight. He exposes the errors, deficiencies of these methods and confronts them with the possibilities of the NDN-system (newborn's somatic development and nutritional state) worked out earlier by him. He thinks the NDF-system to be able to express simultaneously and exactly the gestational age, weight- and length-development, state of being fed of the newborns and the relation to the populational average, the fact and type of retardation, as well. The informational means of NDF-system in NDF-index. The NDF-system makes it possible to break down the birth-weight centric view as it offers a more suitable and qualified method than used before to describe the maturity and somatic development and the classifying of the newborns on the basis of these.

Communication: A combined periodic density functional and incremental wave-function-based approach for the dispersion-accounting time-resolved dynamics of ⁴He nanodroplets on surfaces: ⁴He/graphene.

PubMed

de Lara-Castells, María Pilar; Stoll, Hermann; Civalleri, Bartolomeo; Causà, Mauro; Voloshina, Elena; Mitrushchenkov, Alexander O; Pi, Martí

2014-10-21

In this work we propose a general strategy to calculate accurate He-surface interaction potentials. It extends the dispersionless density functional approach recently developed by Pernal et al. [Phys. Rev. Lett. 103, 263201 (2009)] to adsorbate-surface interactions by including periodic boundary conditions. We also introduce a scheme to parametrize the dispersion interaction by calculating two- and three-body dispersion terms at coupled cluster singles and doubles and perturbative triples (CCSD(T)) level via the method of increments [H. Stoll, J. Chem. Phys. 97, 8449 (1992)]. The performance of the composite approach is tested on (4)He/graphene by determining the energies of the low-lying selective adsorption states, finding an excellent agreement with the best available theoretical data. Second, the capability of the approach to describe dispersionless correlation effects realistically is used to extract dispersion effects in time-dependent density functional simulations on the collision of (4)He droplets with a single graphene sheet. It is found that dispersion effects play a key role in the fast spreading of the (4)He nanodroplet, the evaporation-like process of helium atoms, and the formation of solid-like helium structures. These characteristics are expected to be quite general and highly relevant to explain experimental measurements with the newly developed helium droplet mediated deposition technique.

Physico-chemical characteristics of ZnO nanoparticles-based discs and toxic effect on human cervical cancer HeLa cells

NASA Astrophysics Data System (ADS)

Sirelkhatim, Amna; Mahmud, Shahrom; Seeni, Azman; Kaus, Noor Haida Mohd.; Sendi, Rabab

2014-10-01

In this study, we investigated physico-chemical properties of zinc oxide nanoparticles (ZnO NPs)-based discs and their toxicity on human cervical cancer HeLa cell lines. ZnO NPs (80 nm) were produced by the conventional ceramic processing method. FESEM analysis indicated dominant structure of nanorods with dimensions 100-500 nm in length, and 20-100 nm in diameter. The high content of ZnO nanorods in the discs probably played significant role in toxicity towards HeLa cells. Structural defects (oxygen vacancies and zinc/oxygen interstitials) were revealed by PL spectra peaks at 370-376 nm and 519-533 nm for the ZnO discs. The structural, optical and electrical properties of prepared sample have influenced the toxicological effects of ZnO discs towards HeLa cell lines via the generation of reactive oxygen species (ROS), internalization, membrane damage, and eventually cell death. The larger surface to volume area of the ZnO nanorods, combined with defects, stimulated enhanced toxicity via ROS generation hydrogen peroxide, hydroxyl radicals, and superoxide anion. The preliminary results confirmed the ZnO-disc toxicity on HeLa cells was significantly associated with the unique physicochemical properties of ZnO NPs and to our knowledge, this is the first cellular study for treatment of HeLa cells with ZnO discs made from 80 nm ZnO particles.

Rapid diagnosis of acanthamoeba keratitis using non-nutrient agar with a lawn of E. coli.

PubMed

Borin, Samuel; Feldman, Ilan; Ken-Dror, Shifra; Briscoe, Daniel

2013-02-27

A patient presented with a corneal foreign body in his only eye. He was treated with prophylactic antibiotics and sent home, but deteriorated. He returned to the hospital 5 days later, and on slit-lamp examination, there was ciliary injection, corneal oedema and a 1 mm × 1 mm corneal abscess with mild anterior uveitis. Corneal scrapings were taken for culture on a non-nutrient agar with a lawn of Escherichia coli, on chocolate agar and on blood agar. He was treated with fortified gentamicin and cefazolin drops. He improved and was discharged 4 days after admission. On day 5, the culture results showed acanthamoeba. He was brought back to the hospital and treated with hourly chlorhexidine drops, ofloxacin six times daily and neomycin/dexamethasone drops once daily. On day 7, he was discharged to continue treatment at home, at which time his visual acuity in that eye was 6/9, and slit-lamp examination showed punctate keratitis and a stromal opacity with mild peripheral infiltration. Culture on non-nutrient agar with a lawn of E. coli is a rapid, reliable and less invasive alternative to corneal biopsy for the diagnosis of acanthamoeba infection. We suggest using this method where acanthamoeba is suspected. Owing to the risk of corneal abscess, orthokeratology should be avoided in an amblyopic patient or an only eye. Acanthamoeba infection may be masked by other eye diseases.

Pro-inflammatory Cytokines Are Involved in Fluoride-Induced Cytotoxic Potential in HeLa Cells.

PubMed

Wang, Hong-Wei; Zhou, Bian-Hua; Cao, Jian-Wen; Zhao, Jing; Zhao, Wen-Peng; Tan, Pan-Pan

2017-01-01

This study was designed to investigate the pro-inflammatory cytokines and their involvement in the cytotoxic potential of fluoride (F) in HeLa cells. HeLa cells were cultured with varying F concentrations (1-50 mg/L) for 48 h, and treatment effects were analyzed. The viability of HeLa cells was determined with a colorimetric method. The concentrations of IL-1β, IL-2, IL-6, and TNF-a in culture supernatant were measured through enzyme linked immunosorbent assay (ELISA). The mRNA expression levels of IL-1β, IL-2, IL-6 and TNF-a were subjected to transcript analysis and quantified through reverse transcription real-time PCR. Results showed that 10, 20 and 50 mg/L F significantly decreased the viability of HeLa cells incubated for 24 and 48 h. With their cytotoxic effect, the concentrations of IL-1β, IL-2, IL-6, and TNF-a decreased significantly in response to F, especially at 20 and 50 mg/L for 48 h. The mRNA expression levels of IL-1β, IL-2, IL-6, and TNF-a were downregulated at 50 mg/L F for 48 h. Therefore, F inhibited HeLa cell growth; as such, F could be used to alleviate the inhibition of pro-inflammatory cytokine expression.

Non-thermal plasma induces mitochondria-mediated apoptotic signaling pathway via ROS generation in HeLa cells.

PubMed

Li, Wei; Yu, K N; Ma, Jie; Shen, Jie; Cheng, Cheng; Zhou, Fangjian; Cai, Zhiming; Han, Wei

2017-11-01

Non-thermal plasma (NTP) has been proposed as a novel therapeutic method for anticancer treatment. Although increasing evidence suggests that NTP selectively induces apoptosis in some types of tumor cells, the molecular mechanisms underlying this phenomenon remain unclear. In this study, we further investigated possible molecular mechanisms for NTP-induced apoptosis of HeLa cells. The results showed that NTP exposure significantly inhibited the growth and viability of HeLa cells. Morphological observation and flow cytometry analysis demonstrated that NTP exposure induced HeLa cell apoptosis. NTP exposure also activated caspase-9 and caspase-3, which subsequently cleaved poly (ADP- ribose) polymerase. Furthermore, NTP exposure suppressed Bcl-2 expression, enhanced Bax expression and translocation to mitochondria, activated mitochondria-mediated apoptotic pathway, followed by the release of cytochrome c. Further studies showed that NTP treatment led to ROS generation, whereas blockade of ROS generation by N-acetyl-l-cysteine (NAC, ROS scavengers) significantly prevented NTP-induced mitochondrial alteration and subsequent apoptosis of HeLa cells via suppressing Bax translocation, cytochrome c and caspase-3 activation. Taken together, our results indicated that NTP exposure induced mitochondria-mediated intrinsic apoptosis of HeLa cells was activated by ROS generation. These findings provide insights to the therapeutic potential and clinical research of NTP as a novel tool in cervical cancer treatment. Copyright © 2017. Published by Elsevier Inc.

SCD-HeFT: Use of RR Interval Statistics for Long-term Risk Stratification for Arrhythmic Sudden Cardiac Death

PubMed Central

Au-yeung, Wan-tai M.; Reinhall, Per; Poole, Jeanne E.; Anderson, Jill; Johnson, George; Fletcher, Ross D.; Moore, Hans J.; Mark, Daniel B.; Lee, Kerry L.; Bardy, Gust H.

2015-01-01

Background In the SCD-HeFT a significant fraction of the congestive heart failure (CHF) patients ultimately did not die suddenly from arrhythmic causes. CHF patients will benefit from better tools to identify if ICD therapy is needed. Objective To identify predictor variables from baseline SCD-HeFT patients’ RR intervals that correlate to arrhythmic sudden cardiac death (SCD) and mortality and to design an ICD therapy screening test. Methods Ten predictor variables were extracted from pre-randomization Holter data from 475 patients enrolled in the SCD-HeFT ICD arm using novel and traditional heart rate variability methods. All variables were correlated to SCD using Mann Whitney-Wilcoxon test and receiver operating characteristic analysis. ICD therapy screening tests were designed by minimizing the cost of false classifications. Survival analysis, including log-rank test and Cox models, was also performed. Results α1 and α2 from detrended fluctuation analysis, the ratio of low to high frequency power, the number of PVCs per hour and heart rate turbulence slope are all statistically significant for predicting the occurrences of SCD (p<0.001) and survival (log-rank p<0.01). The most powerful multivariate predictor tool using the Cox Proportional Hazards was α2 with a hazard ratio of 0.0465 (95% CI: 0.00528 – 0.409, p<0.01). Conclusion Predictor variables from RR intervals correlate to the occurrences of SCD and distinguish survival among SCD-HeFT ICD patients. We believe SCD prediction models should incorporate Holter based RR interval analysis to refine ICD patient selection especially in removing patients who are unlikely to benefit from ICD therapy. PMID:26096609

Rapid virtual H&E histology of breast tissue specimens using a compact fluorescence nonlinear microscope

PubMed Central

Cahill, Lucas C.; Giacomelli, Michael G.; Yoshitake, Tadayuki; Vardeh, Hilde; Faulkner-Jones, Beverly E.; Connolly, James L.; Sun, Chi-Kuang; Fujimoto, James G.

2017-01-01

Up to 40% of patients undergoing breast conserving surgery for breast cancer require repeat surgeries due to close to or positive margins. The lengthy processing required for evaluating surgical margins by standard paraffin embedded histology precludes its use during surgery and therefore, technologies for rapid evaluation of surgical pathology could improve the treatment of breast cancer by reducing the number of surgeries required. We demonstrate real-time histological evaluation of breast cancer surgical specimens by staining specimens with acridine orange (AO) and sulforhodamine 101 (SR101) analogously to hematoxylin and eosin (H&E) and then imaging the specimens with fluorescence nonlinear microscopy (NLM) using a compact femtosecond fiber laser. A video-rate computational light absorption model was used to produce realistic virtual H&E images of tissue in real time and in three dimensions. NLM imaging could be performed to depths of 100 µm below the tissue surface, which is important since many surgical specimens require subsurface evaluation due to artifacts on the tissue surface from electrocautery, surgical ink or debris from specimen handling. We validate this method by expert review of NLM images compared to formalin fixed, paraffin embedded (FFPE) H&E histology. Diagnostically important features such as normal terminal ductal lobular units, fibrous and adipose stromal parenchyma, inflammation, invasive carcinoma, and in-situ lobular and ductal carcinoma were present in NLM images associated with pathologies identified on standard FFPE H&E histology. We demonstrate that AO and SR101 were extracted to undetectable levels after FFPE processing and fluorescence in situ hybridization (FISH) HER2 amplification status was unaffected by the NLM imaging protocol. This method potentially enables cost-effective, real-time histological guidance of surgical resections. PMID:29131161

Tidal Volume Single Breath Washout of Two Tracer Gases - A Practical and Promising Lung Function Test

PubMed Central

Singer, Florian; Stern, Georgette; Thamrin, Cindy; Fuchs, Oliver; Riedel, Thomas; Gustafsson, Per; Frey, Urs; Latzin, Philipp

2011-01-01

Background Small airway disease frequently occurs in chronic lung diseases and may cause ventilation inhomogeneity (VI), which can be assessed by washout tests of inert tracer gas. Using two tracer gases with unequal molar mass (MM) and diffusivity increases specificity for VI in different lung zones. Currently washout tests are underutilised due to the time and effort required for measurements. The aim of this study was to develop and validate a simple technique for a new tidal single breath washout test (SBW) of sulfur hexafluoride (SF6) and helium (He) using an ultrasonic flowmeter (USFM). Methods The tracer gas mixture contained 5% SF6 and 26.3% He, had similar total MM as air, and was applied for a single tidal breath in 13 healthy adults. The USFM measured MM, which was then plotted against expired volume. USFM and mass spectrometer signals were compared in six subjects performing three SBW. Repeatability and reproducibility of SBW, i.e., area under the MM curve (AUC), were determined in seven subjects performing three SBW 24 hours apart. Results USFM reliably measured MM during all SBW tests (n = 60). MM from USFM reflected SF6 and He washout patterns measured by mass spectrometer. USFM signals were highly associated with mass spectrometer signals, e.g., for MM, linear regression r-squared was 0.98. Intra-subject coefficient of variation of AUC was 6.8%, and coefficient of repeatability was 11.8%. Conclusion The USFM accurately measured relative changes in SF6 and He washout. SBW tests were repeatable and reproducible in healthy adults. We have developed a fast, reliable, and straightforward USFM based SBW method, which provides valid information on SF6 and He washout patterns during tidal breathing. PMID:21423739

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

Kajita, Shin; Yoshida, Tomoko; Kitaoka, Daiki

It has been found recently that low-energy helium (He) plasma irradiation to tungsten (W) leads to the growth of W nanostructures on the surface. The process to grow the nanostructure is identified as a self-growth process of He bubbles and has a potential to open up a new plasma processing method. Here, we show that the metallic nanostructure formation process by the exposure to He plasma can occur in various metals such as, titanium, nickel, iron, and so on. When the irradiation conditions alter, the metallic cone arrays including nanobubbles inside are formed on the surface. Different from W cases,more » other processes than growth of fiberform structure, i.e., physical sputtering and the growth of large He bubbles, can be dominant on other metals during irradiation; various surface morphology changes can occur. The nanostructured W, part of which was oxidized, has revealed a significant photocatalytic activity under visible light (wavelength >700 nm) in decolorization of methylene blue without any co-catalyst.« less

Descartes' dreams.

PubMed

Withers, Robert

2008-11-01

René Descartes is often regarded as the 'father of modern philosophy'. He was a key figure in instigating the scientific revolution that has been so influential in shaping our modern world. He has been revered and reviled in almost equal measure for this role; on the one hand seen as liberating science from religion, on the other as splitting soul from body and man from nature. He dates the founding of his philosophical methods to the night of 10(th) November 1619 and in particular to three powerful dreams he had that night. This article utilizes Descartes' own interpretations of the dreams, supported by biographical material, as well as contemporary neuroscientific and psychoanalytic theory, to reach a new understanding of them. It is argued that the dreams can be understood as depicting Descartes' personal journey from a state of mind-body dissociation to one of mind-body deintegration. This personal journey may have implications for a parallel journey from Renaissance to modern culture and from modernity to post-modern culture.

Multispectral image enhancement for H&E stained pathological tissue specimens

NASA Astrophysics Data System (ADS)

Bautista, Pinky A.; Abe, Tokiya; Yamaguchi, Masahiro; Ohyama, Nagaaki; Yagi, Yukako

2008-03-01

The presence of a liver disease such as cirrhosis can be determined by examining the proliferation of collagen fiber from a tissue slide stained with special stain such as the Masson's trichrome(MT) stain. Collagen fiber and smooth muscle, which are both stained the same in an H&E stained slide, are stained blue and pink respectively in an MT-stained slide. In this paper we show that with multispectral imaging the difference between collagen fiber and smooth muscle can be visualized even from an H&E stained image. In the method M KL bases are derived using the spectral data of those H&E stained tissue components which can be easily differentiated from each other, i.e. nucleus, cytoplasm, red blood cells, etc. and based on the spectral residual error of fiber weighting factors are determined to enhance spectral features at certain wavelengths. Results of our experiment demonstrate the capability of multispectral imaging and its advantage compared to the conventional RGB imaging systems to delineate tissue structures with subtle colorimetric difference.

Measuring gas temperature during spin-exchange optical pumping process

NASA Astrophysics Data System (ADS)

Normand, E.; Jiang, C. Y.; Brown, D. R.; Robertson, L.; Crow, L.; Tong, X.

2016-04-01

The gas temperature inside a Spin-Exchange Optical Pumping (SEOP) laser-pumping polarized 3He cell has long been a mystery. Different experimental methods were employed to measure this temperature but all were based on either modelling or indirect measurement. To date there has not been any direct experimental measurement of this quantity. Here we present the first direct measurement using neutron transmission to accurately determine the number density of 3He, the temperature is obtained using the ideal gas law. Our result showed a surprisingly high gas temperature of 380°C, compared to the 245°C of the 3He cell wall temperature and 178°C of the optical pumping oven temperature. This experiment result may be used to further investigate the unsolved puzzle of the "X-factor" in the SEOP process which places an upper bound to the 3He polarization that can be achieved. Additional spin relaxation mechanisms might exist due to the high gas temperature, which could explain the origin of the X-factor.

Helium isotope enrichment by resonant tunneling through nanoporous graphene bilayers.

PubMed

Mandrà, Salvatore; Schrier, Joshua; Ceotto, Michele

2014-08-21

Graphene is impermeable to gases, but introducing subnanometer pores can allow for selective gas separation. Because graphene is only one atom thick, tunneling can play an important role, especially for low-mass gases such as helium, and this has been proposed as a means of separating (3)He from (4)He. In this paper, we consider the possibility of utilizing resonant tunneling of helium isotopes through nanoporous graphene bilayers. Using a model potential fit to previously reported DFT potential energy surfaces, we calculate the thermal rate constant as a function of interlayer separation using a recently described time-independent method for arbitrary multibarrier potentials. Resonant transmission allows for the total flux rate of (3)He to remain the same as the best-known single-barrier pores but doubles the selectivity with respect to (4)He when the optimal interlayer spacing of 4.6 Å is used. The high flux rate and selectivity are robust against variations of the interlayer spacing and asymmetries in the potential that may occur in experiment.

THM and primordial nucleosynthesis: Results and perspectives

NASA Astrophysics Data System (ADS)

Pizzone, R. G.; Spartá, R.; Bertulani, C.; Spitaleri, C.; La Cognata, M.; Lamia, L.; Tumino, A.

2017-09-01

Big Bang Nucleosynthesis (BBN) requires several nuclear physics inputs and nuclear reaction rates. An up-to-date compilation of direct cross sections of d(d,p)t, d(d,n) 3 He and 3 He(d,p) 4 He reactions is given, being these ones among the most uncertain bare-nucleus cross sections. An intense experimental effort has been carried on in the last decade to apply the Trojan Horse Method (THM) to study reactions of relevance for the BBN and measure their astrophysical S( E) -factor. The reaction rates and the relative error for the four reactions of interest are then numerically calculated in the temperature ranges of relevance for BBN ( 0.01

Nathaniel Hodges (1629-1688): Plague doctor.

PubMed

Duffin, Christopher J

2016-02-01

Nathaniel Hodges was the son of Thomas Hodges (1605-1672), an influential Anglican preacher and reformer with strong connections in the political life of Carolingian London. Educated at Westminster School, Trinity College Cambridge and Christ Church College, Oxford, Nathaniel established himself as a physician in Walbrook Ward in the City of London. Prominent as one of a handful of medical men who remained in London during the time of the Great Plague of 1665, he wrote the definitive work on the outbreak. His daily precautions against contracting the disease included fortifying himself with Théodore de Mayerne's antipestilential electuary and the liberal consumption of Sack. Hodges' approach to the treatment of plague victims was empathetic and based on the traditional Galenic method rather than Paracelsianism although he was pragmatic in the rejection of formulae and simples which he judged from experience to be ineffective. Besieged by financial problems in later life, his practice began to fail in the 1680s and he eventually died in a debtor's prison. © The Author(s) 2014.

Mechanical properties and electrical conductivity of Al 6101 and 6201 alloys processed by hydro-extrusion

NASA Astrophysics Data System (ADS)

Pakiela, Z.; Ludwichowska, K.; Ferenc, J.; Kulczyk, M.

2014-08-01

The aim of this work was to produce a material with high strength and electrical conductivity. Two aluminium alloys: Al 6101 and 6201 were used for investigation. Improvement of mechanical properties was obtained by severe plastic deformation, using Hydrostatic Extrusion (HE). To examine mechanical properties of the materials microhardness and tensile tests were carried out. Furthermore, the microstructure analysis was carried out using TEM and light microscopy. Electrical conductivity of materials was measured by 4-wire method. It was found that in the material processed by HE tensile strength and microhardness increased about twice. The biggest strength of 356 MPa was obtained for alloy 6201 after HE. In this case the reduction of a diameters from 20 to 5 mm was used. Examination of the microstructure revealed that as a result of HE grain size refinement to 0.5 micrometer occurred. It was also found that the material has the electric conductivity of about 52% IACS.

Arpad Gerster and Max Thorek contributions to American surgery.

PubMed

Langer, Robert M

2009-01-01

The legacy and the influence on American surgery is discussed of two Hungarian born surgeons: Arpad Gerster (1848-1923) and Max Thorek (1880-1960). Both of them were born in Northern Hungary, then part of the Austro-Hungarian Monarchy, today Slovakia. Gerster got his medical education in Vienna The influence of Theodor Billroth left everlasting impressions in him. In 1874 he arrived in New York and became the first doctor in town who practiced exclusively surgery. He became an attending surgeon in The German Hospital and later at Mount Sinai Hospital. Gerster modernized the hospital's functions and services, introducing the rotation system, and also made the original observation that dissemination of cancer may be caused by surgery. His aseptic methods were revolutionary at the time. Max Thorek arrived in Chicago in 1897. With a fantastic endurance he overwhelmed all barriers and became a doctor. He started his practice in one of Chicago's poor immigrant neighborhoods, but stepwise he could excel and in 1911 he co-founded The American Hospital. His ideas of modernizing surgery became reality. Thorek is one of the first who practiced plastic surgery, and his contribution by writing about surgical errors and safeguards became a great success. He founded the International College of Surgeons, a result of his widespread relations among surgeons all over the world. The parallels in the lives of these great surgeons: solid education, knowledge of languages, talent for music, literature, and arts, creative thinking combined with hard work, good humor, as well as a social conscience led them to make groundbreaking contributions to American and international surgery.

Rotationally inelastic collisions of He and Ar with NaK: Experiment and theory

NASA Astrophysics Data System (ADS)

Malenda, R. F.; Jones, J.; Faust, C.; Richter, K.; Wolfe, C. M.; Hickman, A. P.; Huennekens, J.; Talbi, D.; Gatti, F.

2012-06-01

We are investigating collisions of the ground (X^1&+circ;) and first excited (A^1&+circ;) electronic states of NaK using both experimental and theoretical methods. Potential surfaces for HeNaK (fixed NaK bond length) are used for coupled channel calculations of cross sections for rotational energy transfer and also for collisional transfer of orientation and alignment. Additional calculations use the MCTDH wavepacket method. The measurements of the A state collisions involve a pump--probe excitation scheme using polarization labeling and laser-induced fluorescence spectroscopy. The pump excites a particular ro-vibrational level (v,J) of the A state from the X state, and the probe laser is scanned over various transitions to the 3^1π state. In addition to strong direct transitions, weak satellite lines are observed that arise from collisionally-induced transitions from the (v,J) level to (v,J'=J+δJ). This method provides information about the cross sections for transfer of population and orientation for A state levels, and it can be adapted to transitions starting in the X state. For the A state we observe a strong δJ=even propensity for both He and Ar perturbers. Preliminary results for the X state do not show this propensity.

Can Single Crystal (U-Th)/He Zircon Ages from Nördlinger Ries Suevite be Linked to Impact-Related Shock Effects?

NASA Astrophysics Data System (ADS)

van Soest, M. C.; Cooper, F. J.; Wartho, J.; Hodges, K.; Buchner, E.; Schmieder, M.; Koeberl, C.

2010-12-01

Dating of impact-related material is difficult especially when pristine impact melt is unavailable. In the absence of such melts, most geochronometers in shocked basement or melt-poor impact rocks yield only partially reset or non-reset ages. In such cases, application of the low closure temperature apatite and zircon (U-Th)/He geochronometers can be successful, since impact-related physical and thermal shock should reset the He systematics in both minerals in most materials affected by the impact. For a proof of concept study on the well-studied Ries impact structure, we (U-Th)/He dated apatites (14.08 ± 0.26 Ma 2σ, n = 5) and zircons (14.26 ± 0.31 Ma 2σ, n = 10) from two Aumühle quarry suevite samples and one Polsingen quarry impact melt rock, which was dated at 14.37 ± 0.30 Ma (2σ) using Ar-Ar stepwise heating of recrystallized K-feldspar melt (Buchner et al., 2010). The (U-Th)/He ages agree well with the 14.37 Ma age, but are slightly younger than the suggested age of 14.59 ± 0.20 Ma (2σ - based on recent, post 1995, Ar-Ar data, Buchner et al., 2010) for the impact structure. However, among the 27 zircons dated, 6 were partially reset (>16Ma), and 11 zircons yielded younger dates (<13.5 Ma).The younger dates are problematic for successful (U-Th)/He dating of impact structures of unknown age, as they would be identified incorrectly as the age of the impact event. The cause for these younger dates may be: a) partial He loss due to a post-impact thermal event, which at Ries is unlikely as there is no geological evidence for such an event; b) compromised He retention due to metamictization by progressive radiation damage; or c) compromised He retention due to impact shock-related effects. The latter two causes can produce similar visual effects on zircon and the He loss mechanism is also similar, i.e. changes in the zircon crystal structure on a micro scale. However, the effects of these processes on zircon have been documented extensively by non-destructive analytical methods such as Raman spectroscopy, single crystal XRD, and SEM. These techniques have provided a means to distinguish shock from radiation damage effects, based on the presence of the high pressure zircon polymorph reidite, at shock levels >20 GPa (Wittmann et al., 2006). In order to establish if these effects can be identified in individual zircons before undertaking (U-Th)/He dating, and thus if these analytical methods can be used to pre-select suitable zircons for dating, 30 Ries zircons have been picked, based on euhedral shape and size, from two suevite samples for non-destructive geochemical and crystal structure studies prior to (U-Th)/He dating. Initial results from Raman spectroscopy indicate reidite is present in >80% of the grains, providing clear evidence for shock, while other grains show extensive amorphization likely due to extreme shock or radiation damage. References: Buchner et al. (2010) MAPS 45, 5: 662-674; Wittman et al. (2006) MAPS 41, 3: 433-454.

A Family of Early English Oculists (1600-1751), With a Reappraisal of John Thomas Woolhouse (1664-1733/1734)

PubMed Central

Leffler, Christopher T; Schwartz, Stephen G

2017-01-01

Introduction: John Thomas Woolhouse (1666-1733/1734), who practiced in Paris, was part of a family with 5 generations of English oculists. Some historians have derided him as a “charlatan” and have criticized him for adhering to the old notion that a cataract was a membrane anterior to the lens. Methods: We reviewed treatises and digital records related to Woolhouse and his family and the handwritten notes of his 1721 lecture series at the Royal Society of Medicine. Results: We have identified 5 generations of oculists in Woolhouse’s family, by the names of Atwood, Stepkins, Ivy, and Beaumont. Woolhouse taught students from across Europe. He was one of the early proponents in Europe, inspired by Asian medical practices, to perform paracentesis to release aqueous for a new condition called hydrophthalmia. In Woolhouse’s system, some of these cases probably described angle-closure glaucoma. He was the first to attach the name glaucoma to the palpably hard eye in 1707. He may also have been the first to teach that a soft eye was unlikely to recover vision. Credit for these teachings has traditionally gone to one of his students, Johannes Zacharias Platner, in 1745. Some historians have stated that he proposed iridectomy as a theoretical procedure, which was later performed by Cheselden. In fact, Woolhouse described techniques he had performed which today would be called pupilloplasty, synechiolysis, or pupillary membrane lysis. He was also a pioneer in dacryocystectomy for chronic dacryocystitis and in congenital cataract surgery. His writings from 1716 onward repeatedly (and correctly) stressed that most of the patients with visual disorders required depression of the crystalline lens (for what he called glaucoma), as opposed to removal of an anterior membrane (which he called cataract). Conclusions: Woolhouse was a bold ophthalmic innovator and teacher who made major contributions which have lasted to this day. Although he did not admit it, he ultimately adopted much of the evolving understanding of the nature of lens opacities. However, his stubborn refusal to adopt the newer semantics has detracted from a full appreciation of his contributions. PMID:28989288

A validation of the 3H/3He method for determining groundwater recharge

NASA Astrophysics Data System (ADS)

Solomon, D. K.; Schiff, S. L.; Poreda, R. J.; Clarke, W. B.

1993-09-01

Tritium and He isotopes have been measured at a site where groundwater flow is nearly vertical for a travel time of 100 years and where recharge rates are spatially variable. Because the mid-1960s 3H peak (arising from aboveground testing of thermonuclear devices) is well-defined, the vertical groundwater velocity is known with unusual accuracy at this site. Utilizing 3H and its stable daughter 3He to determine groundwater ages, we compute a recharge rate of 0.16 m/yr, which agrees to within about 5% of the value based on the depth of the 3H peak (measured both in 1986 and 1991) and two-dimensional modeling in an area of high recharge. Zero 3H/3He age occurs at a depth that is approximately equal to the average depth of the annual low water table, even though the capillary fringe extends to land surface during most of the year at the study site. In an area of low recharge (0.05 m/yr) where the 3H peak (and hence the vertical velocity) is also well-defined, the 3H/3He results could not be used to compute recharge because samples were not collected sufficiently far above the 3H peak; however, modeling indicates that the 3H/3He age gradient near the water table is an accurate measure of vertical velocities in the low-recharge area. Because 3H and 3He have different diffusion coefficients, and because the amount of mechanical mixing is different in the area of high recharge than in the low-recharge area, we have separated the dispersive effects of mechanical mixing from molecular diffusion. We estimate a longitudinal dispersivity of 0.07 m and effective diffusion coefficients for 3H (3HHO) and 3He of 2.4×10-5 and 1.3×10-4 m2/day, respectively. Although the 3H/3He age gradient is an excellent indicator of vertical groundwater velocities above the mid-1960s 3H peak, dispersive mixing and diffusive loss of 3He perturb the age gradient near and below the 3H peak.

Workshop: Advancing the Theory and Methods for Understanding Employment Effects of Environmental Regulation (2012)

EPA Pesticide Factsheets

he Environmental Protection Agency's National Center for Environmental Economics and Professor V. Kerry Smith (Arizona State University), with support from Abt Associates, convened a one-day workshop exploring theory and methods relevant to the employment.

Generalized Jastrow Variational Method for Liquid HELIUM-3-HELIUM-4 Mixtures at T = 0 K.

NASA Astrophysics Data System (ADS)

Mirabbaszadeh, Kavoos

Microscopic theory of dilute liquid { ^3 He}-{^4 He} mixtures is of great interest, because it provides a physical realization of a nearly degenerate weakly interacting Fermion system. An understanding of properties of the mixtures has received considerable attention both theoretically and experimentally over the past thirty years. We present here a variational procedure based on the Jastrow function for the ground state of {^3 He}- {^4 He} mixtures by minimizing the total energy of the mixture using the hypernetted-chain (HNC) approximation and the Percus-Yevick (PY) approximation for the two body correlation functions. Our goal is to compute from first principles the internal energy of the system and the various two body correlation functions at various densities and compare the results with experiment. The Jastrow variational method for the ground state energy of liquid {^4 He} consists of the following ansatz for the wave function Psi_alpha {rm(vec r_{1 alpha},} {vec r_{2alpha},} dots, {vec r_{N _alpha})} = prod _{rm i < j} {rm f_ {alphaalpha}(r_{ij}). } For a {^3 He } system the corresponding ansatz is Psi_beta {rm( vec r_{1beta},} {vec r_{2beta },} dots, {vec r_{N_beta})} = {[prod _{i < j} f_{betabeta }(r_{ij})]} Phi {rm( vec r_{1beta},} {vec r_{2beta },} dots, {vec r_{Nbeta}),} where Phi is a Slater determinant of plane waves for the ground state of the Fermion system. The total energy per particle can be written in the form: E = x_sp{alpha}{2} E_{alphaalpha} + x_sp{beta}{2 }E_{betabeta } + 2x_{alpha} x_{beta}E _{alphabeta}, where E_{alphaalpha} , E_{betabeta} , E_{alphabeta} are unknown parameters to be determined from a microscopic theory. Using the Jastrow wave function Psi for the mixture, a general expression is given for the ground state energy in terms of the two body potential and two and three body correlation functions. The Kirkwood Super-position Approximation (KSA) is used for the three-body correlation functions. The antisymmetry of the wave function for Fermions is incorporated following the procedure given earlier by Lado, Inguva and Smith. This procedure for treating the antisymmetry of the wave function simplifies the equations for the two-body correlation functions considerably. The equations for the correlation functions are solved in the hypernetted-chain approximation. Once the two-particle correlation functions for the mixture ( ^3He-^4He) have been obtained, the energy is minimized with respect to the variational parameters involved in the Jastrow wave function. The binding energy and the optimal correlation functions are then obtained as a function of the concentration of ^3He atoms in the mixture. (Abstract shortened with permission of author.).

Ground-state properties of 4He and 16O extrapolated from lattice QCD with pionless EFT

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

Contessi, L.; Lovato, A.; Pederiva, F.

Here, we extend the prediction range of Pionless Effective Field Theory with an analysis of the ground state of 16O in leading order. To renormalize the theory, we use as input both experimental data and lattice QCD predictions of nuclear observables, which probe the sensitivity of nuclei to increased quark masses. The nuclear many-body Schrödinger equation is solved with the Auxiliary Field Diffusion Monte Carlo method. For the first time in a nuclear quantum Monte Carlo calculation, a linear optimization procedure, which allows us to devise an accurate trial wave function with a large number of variational parameters, is adopted.more » The method yields a binding energy of 4He which is in good agreement with experiment at physical pion mass and with lattice calculations at larger pion masses. At leading order we do not find any evidence of a 16O state which is stable against breakup into four 4He, although higher-order terms could bind 16O.« less

Use of SRIM and Garfield with Geant4 for the characterization of a hybrid 10B/3He neutron detector

NASA Astrophysics Data System (ADS)

van der Ende, B. M.; Rand, E. T.; Erlandson, A.; Li, L.

2018-06-01

This paper describes a method for more complete neutron detector characterization using Geant4's Monte Carlo methods for characterizing overall detector response rate and Garfield interfaced with SRIM for the simulation of the detector's raw pulses, as applied to a hybrid 10B/3He detector. The Geant4 models characterizing the detector's interaction with a 252Cf point source and parallel beams of mono-energetic neutrons (assuming ISO 8529 reference energy values) compare and agree well with calibrated 252Cf measurements to within 6.4%. Validated Geant4 model outputs serve as input to Garfield+SRIM calculations to provide meaningful pulse height spectra. Modifications to Garfield for this work were necessary to account for simultaneous tracking of electrons resulting from proton and triton reaction products from a single 3He neutron capture event, and it was further necessary to interface Garfield with the energy loss, range, and straggling calculations provided by SRIM. Individual raw pulses generated by Garfield+SRIM are also observed to agree well with experimentally measured raw pulses from the detector.

Accumulation of natural SF6 in the sedimentary aquifers of the North China Plain as a restriction on groundwater dating.

PubMed

von Rohden, Christoph; Kreuzer, Andreas; Chen, Zongyu; Aeschbach-Hertig, Werner

2010-09-01

We employed environmental tracers ((3)H-(3)He, SF(6)) in a study investigating the groundwater recharge in the North China Plain (NCP), a sedimentary aquifer system consisting of fluvial and alluvial river deposits near the city of Shijiazhuang. The (3)H-(3)He dating method revealed reasonable results for the young groundwater with ages covering the range of recent to ~40 a. SF(6) samples were taken in parallel for independent dating and to compare the applicability of both methods. However, the SF(6)-results are influenced and, in part, dominated by a systematic non-atmospheric component, revealing that the dating with SF(6) is unreliable in this region. A correlation of non-atmospheric SF(6) and (3)H-(3)He ages suggests a continuous accumulation of natural SF(6) in the groundwater of the NCP aquifers. Although terrigenic SF(6) has previously been associated with crystalline or igneous rocks, our results indicate that it can also be accumulated in sandy aquifers on the timescale relevant for SF(6) dating.

Ground-state properties of 4He and 16O extrapolated from lattice QCD with pionless EFT

DOE PAGES

Contessi, L.; Lovato, A.; Pederiva, F.; ...

2017-07-26

Here, we extend the prediction range of Pionless Effective Field Theory with an analysis of the ground state of 16O in leading order. To renormalize the theory, we use as input both experimental data and lattice QCD predictions of nuclear observables, which probe the sensitivity of nuclei to increased quark masses. The nuclear many-body Schrödinger equation is solved with the Auxiliary Field Diffusion Monte Carlo method. For the first time in a nuclear quantum Monte Carlo calculation, a linear optimization procedure, which allows us to devise an accurate trial wave function with a large number of variational parameters, is adopted.more » The method yields a binding energy of 4He which is in good agreement with experiment at physical pion mass and with lattice calculations at larger pion masses. At leading order we do not find any evidence of a 16O state which is stable against breakup into four 4He, although higher-order terms could bind 16O.« less

Dynamism to promote reproductive medicine and its development, Rihachi Iizuka.

PubMed

Sueoka, K

2001-12-01

Rihachi Iizuka has contributed strong leadership for the remarkable development of reproductive medicine which has undergone a complete transformation in the previous half century. The Keio University Hospital introduced artificial insemination as the first assisted reproductive technology in Japan. As it follows, lizuka and his colleagues first reported the live birth of a female infant in August 1949 after heterologous insemination: AID. Iizuka and his colleagues were also among the first to successfully inseminate a woman with sperm that had been frozen. He developed the new cryopreservation medium for human semen called "KS Cryo-medium". He also developed semen preparation methods of washing and concentrating sperm counts by centrifugation with Percoll (colloidal silica derivative) solution for oligozoospermic patients. These methods are broadly used in the clinical field. Furthermore, he developed the X-, Y-bearing sperm preseparation method using Percoll which is the so-called "gender selection" procedure for preventing X-linked genetic disorders. The most striking assisted reproductive technology was in vitro fertilization first carried out in Britain. Prior to the clinical application in Japan, the Japan Society of Fertilization and Implantation was established as the main organ for the exchange of official scientific information by lizuka in 1982. As rapid development and spreading of in vitro fertilization and its implicated technologies, lizuka and his colleague of the department had the first success of offspring following embryo freezing and thawing in Japan which was performed at the Tokyo Dental College Ichikawa General Hospital. Already the numbers of offspring following in vitro fertilization treatment has risen to approximately 1% of births in Japan. Rihachi lizuka still undertakes the responsibility for reproductive medicine as he has done so far.

Apparent diffusion coefficient of hyperpolarized (3)He with minimal influence of the residual gas in small animals.

PubMed

Carrero-González, L; Kaulisch, T; Ruiz-Cabello, J; Pérez-Sánchez, J M; Peces-Barba, G; Stiller, D; Rodríguez, I

2012-09-01

The apparent diffusion coefficient (ADC) of hyperpolarized (HP) gases is a parameter that reflects changes in lung microstructure. However, ADC is dependent on many physiological and experimental variables that need to be controlled or specified in order to ensure the reliability and reproducibility of this parameter. A single breath-hold experiment is desirable in order to reduce the amount of consumed HP gas. The application of a positive end-expiratory pressure (PEEP) causes an increase in the residual gas volume. Depending on the applied PEEP, the ratio between the incoming and residual gas volumes will change and the ADC will vary, as long as both gases do not have the same diffusion coefficient. The most standard method for human applications uses air for breathing and a bolus of pure HP (3)He for MRI data acquisition. By applying this method in rats, we have demonstrated that ADC values are strongly dependent on the applied PEEP, and therefore on the residual gas volume in the lung. This outcome will play an important role in studies concerning certain diseases, such as emphysema, which is characterized by an increase in the residual volume. Ventilation with an oxygen-helium mixture (VOHeM) is a proposed single breath-hold method that uses two different gas mixtures (O(2)-(4)He for ventilation and HP (3)He-N(2) for imaging). The concentration of each gas in its respective mixture was calculated in order to obtain the same diffusion coefficient in both mixtures. ADCs obtained from VOHeM are independent of PEEP, thus minimizing the effect of the different residual volumes. Copyright © 2012 John Wiley & Sons, Ltd.

Applications of Cosmogenic He-3 and Ne-21 Dating to Glacial Moraines in Antarctica and California

NASA Astrophysics Data System (ADS)

Sams, S.; Morgan, D. J.; Balco, G.; Putkonen, J.; Bibby, T.

2015-12-01

The depositional age of moraines can be determined through cosmogenic nuclide exposure dating. These ages are useful in establishing a glacial history of an area and ascribing age constraints to transport processes. Be-10 is the most common nuclide used for exposure dating today, but this method is both expensive and time consuming because it requires analysis by accelerator mass spectrometry (AMS). He-3 and Ne-21 can be analyzed using noble gas mass spectrometry, which is more cost efficient than AMS and requires less chemical preparation. We collected samples from areas in Moraine Canyon, Antarctica (86.10° S, 157.75° W), which is a dry valley in the Transantarctic Mountains. Dolerite boulders along a transect of recessional moraines were sampled in the typical fashion of using a large piece of the boulder for analysis. Pyroxene minerals have been separated from these samples following the method of Bromley et al. (2014) using hydrofluoric acid. Exposure ages will be calculated from the He-3 concentrations in them. In the Mono Lake area of California, moraines were sampled from Bloody Canyon and McGee Creek sites. Instead of collecting a sample from an individual boulder, we collected approximately 25 granitic pebbles (1-3 cm) from 4-6 sites along the crest of the moraines following the method of Briner (2009). Each suite of pebbles was crushed together, and quartz minerals were separated from the agglomeration of pebbles. Cosmogenic Ne-21 will be measured from these samples to determine their exposure age. From these two field sites, we will use He-3 and Ne-21 to better understand the timing and extent of glaciation in these areas.

Effect of nickel silicide gettering on metal-induced crystallized polycrystalline-silicon thin-film transistors

NASA Astrophysics Data System (ADS)

Kim, Hyung Yoon; Seok, Ki Hwan; Chae, Hee Jae; Lee, Sol Kyu; Lee, Yong Hee; Joo, Seung Ki

2017-06-01

Low-temperature polycrystalline-silicon (poly-Si) thin-film transistors (TFTs) fabricated via metal-induced crystallization (MIC) are attractive candidates for use in active-matrix flat-panel displays. However, these exhibit a large leakage current due to the nickel silicide being trapped at the grain boundaries of the poly-Si. We reduced the leakage current of the MIC poly-Si TFTs by developing a gettering method to remove the Ni impurities using a Si getter layer and natively-formed SiO2 as the etch stop interlayer. The Ni trap state density (Nt) in the MIC poly-Si film decreased after the Ni silicide gettering, and as a result, the leakage current of the MIC poly-Si TFTs decreased. Furthermore, the leakage current of MIC poly-Si TFTs gradually decreased with additional gettering. To explain the gettering effect on MIC poly-Si TFTs, we suggest an appropriate model. He received the B.S. degree in School of Advanced Materials Engineering from Kookmin University, Seoul, South Korea in 2012, and the M.S. degree in Department of Materials Science and Engineering from Seoul National University, Seoul, South Korea in 2014. He is currently pursuing the Ph.D. degree with the Department of Materials Science and Engineering, Seoul National University, Seoul. He is involved in semiconductor device fabrication technology and top-gate polycrystalline-silicon thin-film transistors. He received the M.S. degree in innovation technology from Ecol Polytechnique, Palaiseau, France in 2013. He is currently pursuing the Ph.D. degree with the Department of Materials Science and Engineering, Seoul National University, Seoul. He is involved in semiconductor device fabrication technology and bottom-gate polycrystalline-silicon thin-film transistors. He is currently pursuing the integrated M.S and Ph.D course with the Department of Materials Science and Engineering, Seoul National University, Seoul. He is involved in semiconductor device fabrication technology and copper-gate polycrystalline-silicon thin-film transistors. He is currently pursuing the integrated M.S and Ph.D course with the Department of Materials Science and Engineering, Seoul National University, Seoul. He is involved in semiconductor device fabrication technology and bottom-gate polycrystalline-silicon thin-film transistors. He is currently pursuing the integrated M.S and Ph.D course with the Department of Materials Science and Engineering, Seoul National University, Seoul. He is involved in semiconductor device fabrication technology and bottom-gate polycrystalline-silicon thin-film transistors. He received the B.S. degree in metallurgical engineering from Seoul National University, Seoul, South Korea, in 1974, and the M.S. and Ph.D. degrees in material science and engineering from Stanford University, Stanford, CA, USA, in 1980 and 1983, respectively. He is currently a Professor with the Department of Materials Science and Engineering, Seoul National University, Seoul.

DSP+FPGA-based real-time histogram equalization system of infrared image

NASA Astrophysics Data System (ADS)

Gu, Dongsheng; Yang, Nansheng; Pi, Defu; Hua, Min; Shen, Xiaoyan; Zhang, Ruolan

2001-10-01

Histogram Modification is a simple but effective method to enhance an infrared image. There are several methods to equalize an infrared image's histogram due to the different characteristics of the different infrared images, such as the traditional HE (Histogram Equalization) method, and the improved HP (Histogram Projection) and PE (Plateau Equalization) method and so on. If to realize these methods in a single system, the system must have a mass of memory and extremely fast speed. In our system, we introduce a DSP + FPGA based real-time procession technology to do these things together. FPGA is used to realize the common part of these methods while DSP is to do the different part. The choice of methods and the parameter can be input by a keyboard or a computer. By this means, the function of the system is powerful while it is easy to operate and maintain. In this article, we give out the diagram of the system and the soft flow chart of the methods. And at the end of it, we give out the infrared image and its histogram before and after the process of HE method.

Cloning and Characterization of the Mouse Hepatitis Virus Receptor

DTIC Science & Technology

1991-02-11

reactivity, but they are readily distinguishable by their host specificity and clinical syndromes . Analysis of murine coronaviruses indicates that...express the HE glycoprotein. The HE gene 23 of MHV-A59 lacks an initiator methionine , and cells infected with MHV-A59 do not make an RNA which would...hepatitis virus. MATERIALS AND METHODS Materials : All radioactive compounds used, a [32p] UTP, a (32P] dCTP, y [32P] ATP, [35S] - methionine and a [35S

The Hyperfine Structure of the Ground State in the Muonic Helium Atoms

NASA Astrophysics Data System (ADS)

Aznabayev, D. T.; Bekbaev, A. K.; Korobov, V. I.

2018-05-01

Non-relativistic ionization energies 3He2+μ-e- and 4He2+μ-e- of helium-muonic atoms are calculated for ground states. The calculations are based on the variational method of the exponential expansion. Convergence of the variational energies is studied by an increasing of a number of the basis functions N. This allows to claim that the obtained energy values have 26 significant digits for ground states. With the obtained results we calculate hyperfine splitting of the muonic helium atoms.

Miscarriages of transmission: body, text, and method.

PubMed

Goodrich, P

An introductory and exploratory attempt to examine the possibility of viewing the famous writings of Judge Daniel Paul Schreber as the intimations of translawyering. Volubly convinced he was becoming a woman, Judge Schreber announced that he would nail his flag to the feminine and was incarcerated as mad for his pains and his pleasures. It is time to release him and to read his work not as madness but as a unique conjunction of desire and law. Copyright © 2016. Published by Elsevier Ltd.

Karl Jaspers' phenomenology in the light of histological and X-ray metaphors.

PubMed

Vlasova, Olga Alexandrovna; Beveridge, Allan

2014-03-01

The study considers the origins of Karl Jaspers' phenomenology. What did phenomenology mean to Jaspers and what was his personal perspective? What metaphors did he associate with it? This paper describes his phenomenological method by using the metaphors of histology and the X-ray. This perspective enables a better understanding, not only of the origins and essence of his phenomenology but also of its value for Jaspers himself. In Jaspers' daily life, he would have been familiar with microscopes and X-ray machines.

Symmetric Resonance Charge Exchange Cross Section Based on Impact Parameter Treatment

NASA Technical Reports Server (NTRS)

Omidvar, Kazem; Murphy, Kendrah; Atlas, Robert (Technical Monitor)

2002-01-01

Using a two-state impact parameter approximation, a calculation has been carried out to obtain symmetric resonance charge transfer cross sections between nine ions and their parent atoms or molecules. Calculation is based on a two-dimensional numerical integration. The method is mostly suited for hydrogenic and some closed shell atoms. Good agreement has been obtained with the results of laboratory measurements for the ion-atom pairs H+-H, He+-He, and Ar+-Ar. Several approximations in a similar published calculation have been eliminated.

[Lifetime achievements of Bogomir B. Mrsulja. 1940-1944].

PubMed

Kostić, Vladimir S

2002-09-01

Bogomir Mrshulja was born on September 18th, 1940 in Lendava. He finished both elementary school and high school in Belgrade and subsequently graduated from the School of Medicine, University of Belgrade in 1965. As an undergraduate he was an assistant at the Biochemistry Department and the subject became his profession for life. The University of Belgrade awarded him a scholarship and in 1968 he defended his MSc thesis entitled Glycogen of the Central Nervous System--Methods of Separation, Fraction Isolation, Regional Distribution and Variations in Different Levels of Deprivation of Paradoxical Sleep. Soon after, in 1970, he defended his PhD thesis, as well: Brain Glycogen and Deprivation of Paradoxical Sleep--Biochemical and Pharmacological Aspects of Glycogenolysis. In the period 1973-1975 he spent 18 months in the capacity of a visiting scientist in the Laboratory for Neuropathology and Neuroanatomic Sciences of the National Institute of Health in Bethesda (USA), and again, twelve more months in the same institution (Laboratory for Neurochemistry) in the capacity of a special expert of this institution (1983-84) where he was the chief investigator of neurochemical sequelae of experimental cerebral ischemia. He started his university career as an assistant professor in 1965; he was elected associated professor in 1970, promoted adjunct professor in 1978, while in 1984 he received the full professorship of biochemistry at the School of Medicine, University of Belgrade. In 1970 he was elected research associate of the "Sinisha Stankovitsh" Institute of Biological Research. He was professor of neurochemistry and Head of Department of Neurosciences of the Center for Multidisciplinary Studies, University of Belgrade. He was the Head of the Institute of Biochemistry and Head, Department of Biochemistry and Specialized Courses in Clinical Biochemistry at the School of Medicine, University of Belgrade. Owing to his original hypothesis on mechanisms of the occurrence of ischemic cerebral edema and possible therapeutic approach, Bogomir Mrshulja was frequently invited to lecture in university centers of USA, Canada, Japan, Germany and former USSR. He also participated at over 50 international congresses and symposia worldwide. In the mid seventies, Bogomir Mrshulja started more intensive studies of pathophysiological events in the course of cerebral ischemia and already with his early papers intrigued the professional circles which was reflected in an exceptionally high number of his citations in international scientific and referential literature, including the textbooks. The research activities of Bogomir Mrshulja was impressively fruitful: he published 183 papers in extenso, out of which 42 in books of international publishers and 6 invited review articles. In all these papers he illustrated extensive knowledge, maturity, originality, critical attitude, high level of creativity and, finally, courage to oppose the conventional principles. It should be pointed out that in his works Bogomir Mrshulja tended to draw conclusions that stimulated both himself and his colleagues, researchers in the related fields, insisting on extensive evaluation and testing of hypotheses, which is easily illustrated by the number of citations of his papers. According to the Science Citation Index, by 1995 he was cited 1700 times in the world literature, and in the period 1995-2002 he was cited 250 more times. Besides, he set up and headed the Laboratory for pathological neurochemistry at the School of Medicine in Belgrade that was the cradle for many outstanding researchers and lecturers that now work at the Schools of Medicine in Belgrade, Nish and Kragujevac, Military Medical Academy, and other institutions countrywide. He insisted on indispensable link between laboratory and clinical work, and, at least in the field of neurosciences, he is one of the pioneers of this kind of dialogue. In the year in which he left us for good (1994) scientific contribution of Bogomir Mrshulja was recognized by his election for the corresponding fellow of the Serbian Academy of Sciences and Arts. In the same year, he also received the October Award of the City of Belgrade for research.

Comparison as an Approach to the Experimental Method

ERIC Educational Resources Information Center

Turner, David A.

2017-01-01

In his proposal for comparative education, Marc Antoinne Jullien de Paris argues that the comparative method offers a viable alternative to the experimental method. In an experiment, the scientist can manipulate the variables in such a way that he or she can see any possible combination of variables at will. In comparative education, or in…

29 CFR 452.122 - Delegates from intermediate bodies; method of election.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 29 Labor 2 2011-07-01 2011-07-01 false Delegates from intermediate bodies; method of election. 452... Delegates from intermediate bodies; method of election. A delegate from an intermediate body who... secret ballot vote of the individual members of the constituent units of that body. He may not...

Including Exceptional Students in Your Instrumental Music Program

ERIC Educational Resources Information Center

Mixon, Kevin

2005-01-01

This article describes the method and adaptations used by the author in including students with special needs in an instrumental music program. To ensure success in the program, the author shares the method he uses to include exceptional students and enumerates some possible adaptations. There are certainly other methods and modifications that…

29 CFR 452.122 - Delegates from intermediate bodies; method of election.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 29 Labor 2 2010-07-01 2010-07-01 false Delegates from intermediate bodies; method of election. 452... Delegates from intermediate bodies; method of election. A delegate from an intermediate body who... secret ballot vote of the individual members of the constituent units of that body. He may not...

Probe measurements of the electron velocity distribution function in beams: Low-voltage beam discharge in helium

NASA Astrophysics Data System (ADS)

Sukhomlinov, V.; Mustafaev, A.; Timofeev, N.

2018-04-01

Previously developed methods based on the single-sided probe technique are altered and applied to measure the anisotropic angular spread and narrow energy distribution functions of charged particle (electron and ion) beams. The conventional method is not suitable for some configurations, such as low-voltage beam discharges, electron beams accelerated in near-wall and near-electrode layers, and vacuum electron beam sources. To determine the range of applicability of the proposed method, simple algebraic relationships between the charged particle energies and their angular distribution are obtained. The method is verified for the case of the collisionless mode of a low-voltage He beam discharge, where the traditional method for finding the electron distribution function with the help of a Legendre polynomial expansion is not applicable. This leads to the development of a physical model of the formation of the electron distribution function in a collisionless low-voltage He beam discharge. The results of a numerical calculation based on Monte Carlo simulations are in good agreement with the experimental data obtained using the new method.

BIOMOLECULAR SENSING FOR BIOLOGICAL PROCESSES AND ENVIRONMENTAL MONITORING APPLICATIONS

EPA Science Inventory

Biomolecular recognition is being increasingly employed as the basis for a variety of analytical methods such as biosensors. he sensitivity, selectivity, and format versatility inherent in these methods may allow them to be adapted to solving a number of analytical problems. ltho...

Path Crossings with Lars Onsager

NASA Astrophysics Data System (ADS)

Yang, Chen Ning

2013-05-01

I first heard of Onsager's name from my M.S. degree thesis adviser J. S. Wang in Kunming, China. Wang had studied the theory of order-disorder transitions with R. H. Fowler in Cambridge, England in the 1930's. He told me one day in 1944-45 that Onsager had produced an exact solution of the Ising model in two dimensions. Wang was a quiet and reserved person. But that day he was evidently quite excited. I can remember still today, half a century later, the tone of admiration bordering on agitation with which he told me about Onsager's paper. I then looked up the paper [26J, but did not understand the strategic plan of Onsager's method. Onsager seemed to have a predilection for calculating commutators at every possible turn without supplying the reasons for so doing...

Dielectric Constant Measurements of Solid 4He

NASA Astrophysics Data System (ADS)

Yin, L.; Xia, J. S.; Huan, C.; Sullivan, N. S.; Chan, M. H. W.

2011-03-01

Careful measurements of the dielectric properties of solid 4He have been carried out down to 35 mK, considerably lower than the temperature range of previous studies. The sample was prepared from high purity gas with 3He concentrations of the order of 200 ppb and were formed by the blocked capillary method. The molar volume of the sample was 20.30 cm3. The dielectric constant of the samples was found to be independent of temperature down to 120 mK before showing a continuous increase with decreasing temperature and saturating below 50 mK. The total increase in ɛ is 2 parts in 10-5. The temperature dependence of ɛ mimics the increase in the resonant frequency found in the torsional oscillator studies and also the increase found in the shear modulus measurements.

Møller-Plesset perturbation energies and distances for HeC(20) extrapolated to the complete basis set limit.

PubMed

Varandas, A J C

2009-02-01

The potential energy surface for the C(20)-He interaction is extrapolated for three representative cuts to the complete basis set limit using second-order Møller-Plesset perturbation calculations with correlation consistent basis sets up to the doubly augmented variety. The results both with and without counterpoise correction show consistency with each other, supporting that extrapolation without such a correction provides a reliable scheme to elude the basis-set-superposition error. Converged attributes are obtained for the C(20)-He interaction, which are used to predict the fullerene dimer ones. Time requirements show that the method can be drastically more economical than the counterpoise procedure and even competitive with Kohn-Sham density functional theory for the title system.

Far Field Modeling Methods For Characterizing Surface Detonations

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

Garrett, A.

2015-10-08

Savannah River National Laboratory (SRNL) analyzed particle samples collected during experiments that were designed to replicate tests of nuclear weapons components that involve detonation of high explosives (HE). SRNL collected the particle samples in the HE debris cloud using innovative rocket propelled samplers. SRNL used scanning electronic microscopy to determine the elemental constituents of the particles and their size distributions. Depleted uranium composed about 7% of the particle contents. SRNL used the particle size distributions and elemental composition to perform transport calculations that indicate in many terrains and atmospheric conditions the uranium bearing particles will be transported long distances downwind.more » This research established that HE tests specific to nuclear proliferation should be detectable at long downwind distances by sampling airborne particles created by the test detonations.« less

Effect of ultrasonic irradiation on mammalian cells and chromosomes in vitro

NASA Technical Reports Server (NTRS)

Roseboro, J. A.; Buchanan, P.; Norman, A.; Stern, R.

1978-01-01

Human peripheral blood and HeLa cells were irradiated in vitro at the ultrasonic frequency of 65 kHz. The whole blood and HeLa cell suspensions were exposed to continuous and pulsed ultrasonic power levels of 0.12, 0.16, 0.72, 1.12 and 2.24 W for a period of one minute. The method of ultrasonic irradiation was carried out with the whole blood or HeLa cell suspensions coupled directly to a cylindrical transducer while heating of the cell suspensions in excess of 41 C was avoided. Irradiated and unirradiated peripheral blood lymphocyte chromosome cultures were prepared and scored for selected numerical and morphological aberrations. There was no significant difference in the frequency of chromosomal aberrations between irradiated and unirradiated cells.

Studies of spin-exchange optical pumping

NASA Astrophysics Data System (ADS)

Chann, Bien

Although we still do not understand fully the alkali-alkali relaxation at pressures of an atmosphere or more, an important part of the spin-relaxation comes from the classical dipole-dipole anisotropic spin-axis interaction acting in triplet dimer molecules. The key observation is the existence of magnetic resonances in the magnetic decoupling curves which are predicted from the spin-axis interaction. We identified a new gas-phase, room temperature spin relaxation that is due to the spin-rotation coupling in bound 129Xe-Xe van der Waals molecules. This 129Xe-Xe molecular spin-relaxation is more than an order of magnitude stronger than the well-known 129 Xe-Xe binary spin-relaxation and is the fundamental spin-relaxation process at gas densities below 14 amagat. With external cavity diode laser array bar, we find, based on tests of several cells, that the power required to reach the same polarization is typically three times lower for the spectrally narrowed laser as compared to the unnarrowed diode array bar. This last result indicates that spectrally narrowed lasers are critical to obtaining the highest noble gas polarizations. Furthermore, we find, circularly polarized light propagating at an angle as small as a few degrees to the external magnetic field does not optically pump the atoms to full transparency and causes excess absorption of the pump beam. We measured the Rb-3He spin-exchange rate coefficients using three different methods. We obtained 6.73 +/- 0.12 x 10 -20 cm3/s for the repolarization method. We deduced the spin-exchange rate coefficient to be 6.61 +/- 0.12 x 10 -20 cm3/s for the rate balance method. The third method uses a temperature dependence relaxation of 3He and the deduced value is 8.85 +/- 0.32 x 10-20 cm3/s. This is about 30% higher than the other two methods. This implies a temperature-dependence wall-relaxation or a large value of anisotropic spin-exchange rate coefficient for Rb-3He and would explain the shortfall 3He measured polarization.

Systematic reviews of health economic evaluations: a protocol for a systematic review of characteristics and methods applied.

PubMed

Luhnen, Miriam; Prediger, Barbara; Neugebauer, Edmund A M; Mathes, Tim

2017-12-02

The number of systematic reviews of economic evaluations is steadily increasing. This is probably related to the continuing pressure on health budgets worldwide which makes an efficient resource allocation increasingly crucial. In particular in recent years, the introduction of several high-cost interventions presents enormous challenges regarding universal accessibility and sustainability of health care systems. An increasing number of health authorities, inter alia, feel the need for analyzing economic evidence. Economic evidence might effectively be generated by means of systematic reviews. Nevertheless, no standard methods seem to exist for their preparation so far. The objective of this study was to analyze the methods applied for systematic reviews of health economic evaluations (SR-HE) with a focus on the identification of common challenges. The planned study is a systematic review of the characteristics and methods actually applied in SR-HE. We will combine validated search filters developed for the retrieval of economic evaluations and systematic reviews to identify relevant studies in MEDLINE (via Ovid, 2015-present). To be eligible for inclusion, studies have to conduct a systematic review of full economic evaluations. Articles focusing exclusively on methodological aspects and secondary publications of health technology assessment (HTA) reports will be excluded. Two reviewers will independently assess titles and abstracts and then full-texts of studies for eligibility. Methodological features will be extracted in a standardized, beforehand piloted data extraction form. Data will be summarized with descriptive statistical measures and systematically analyzed focusing on differences/similarities and methodological weaknesses. The systematic review will provide a detailed overview of characteristics of SR-HE and the applied methods. Differences and methodological shortcomings will be detected and their implications will be discussed. The findings of our study can improve the recommendations on the preparation of SR-HE. This can increase the acceptance and usefulness of systematic reviews in health economics for researchers and medical decision makers. The review will not be registered with PROSPERO as it does not meet the eligibility criterion of dealing with clinical outcomes.

26 CFR 1.669(c)-3A - Information requirements with respect to beneficiary.

Code of Federal Regulations, 2010 CFR

2010-04-01

... year for which a recomputation is required under either the exact method or the short-cut method. Such... computed under paragraph (c) of § 1.669(b)-1A (the short-cut method) shall be deemed to be the amount of... this rule where the short-cut method is not permitted. If he cannot furnish the information required...

26 CFR 1.668(b)-4A - Information requirements with respect to beneficiary.

Code of Federal Regulations, 2010 CFR

2010-04-01

... which a recomputation is required under either the exact method or the short-cut method. Such... computed under paragraph (c) of § 1.668(b)-1A (the short-cut method) shall be deemed to be the amount of... this rule where the short-cut method is not permitted. If he cannot furnish the information required...

Bruce Bugbee | NREL

Science.gov Websites

primarily focused on semiparametric regression, functional data, and variational approximation methods Anderson Cancer Center where he contributed to efforts to study various statistical questions in

A new method to determine the interstellar reddening towards WN stars

NASA Technical Reports Server (NTRS)

Conti, Peter S.; Morris, Patrick W.

1990-01-01

An empirical approach to determine the redding in WN stars is presented, in which the measured strengths of the emission lines of He II at 1640 and 4686 A are used to estimate the extinction. The He II emission lines at these wavelengths are compared for a number of WN stars in the Galaxy and the LMC. It is shown that the equivalent width ratios are single valued and are independent of the spectral subtypes. The reddening for stars in the Galaxy is derived using a Galactic extinction law and observed line flux ratios, showing good agreement with previous determinations of reddening. The possible application of the method to study the absorption properties of the interstellar medium in more distant galaxies is discussed.

FIBER AND INTEGRATED OPTICS. OTHER TOPICS IN QUANTUM ELECTRONICS: Modulation method for reducing long-term drift of the emission frequency of an He-Ne laser (λ = 0.63 μm) generating two orthogonally polarized electromagnetic waves

NASA Astrophysics Data System (ADS)

Vitushkin, L. F.; Zakharenko, Yu G.; Smirnov, M. Z.

1990-05-01

Theoretical and experimental investigations were made of the principal physical factors responsible for a long-term drift of the frequency of the radiation generated in a stabilized two-frequency He-Ne laser with internal mirrors, emitting two orthogonally polarized electromagnetic waves. When zero difference between the intensities was controlled by a modulation method and the frequency was set before each measurement, a long-term (over a period of a year) frequency drift did not exceed 10 - 8, but in the absence of such control the drift could reach 5 × 10 - 8.

Grooms receives 2011 Donald L. Turcotte Award

NASA Astrophysics Data System (ADS)

2012-02-01

Ian Grooms has been awarded the AGU Donald L. Turcotte Award, given annually to recent Ph.D. recipients for outstanding dissertation research that contributes directly to the field of nonlinear geophysics. Grooms's thesis is entitled “Asymptotic and numerical methods for rapidly rotating buoyant flow.” He presented an invited talk and was formally presented with the award at the 2011 AGU Fall Meeting, held 5-9 December in San Francisco, Calif. Grooms received his B.S. in mathematics from the College of William and Mary, Williamsburg, Va., in 2005. He received a Ph.D. in applied mathematics in 2011 under the supervision of Keith Julien at the University of Colorado at Boulder. His research interests include asymptotic and numerical methods for multiscale problems in geophysical fluid dynamics.

Sherlock Holmes: scientific detective.

PubMed

Snyder, Laura J

2004-09-01

Sherlock Holmes was intended by his creator, Arthur Conan Doyle, to be a 'scientific detective'. Conan Doyle criticized his predecessor Edgar Allan Poe for giving his creation - Inspector Dupin - only the 'illusion' of scientific method. Conan Doyle believed that he had succeeded where Poe had failed; thus, he has Watson remark that Holmes has 'brought detection as near an exact science as it will ever be brought into the world.' By examining Holmes' methods, it becomes clear that Conan Doyle modelled them on certain images of science that were popular in mid- to late-19th century Britain. Contrary to a common view, it is also evident that rather than being responsible for the invention of forensic science, the creation of Holmes was influenced by the early development of it.

Nigeria using more condoms.

PubMed

1997-09-01

Marie Stopes International says a project it supports in Nigeria is making good progress in its efforts to promote the use of condoms to protect against STDs and for contraception. The program, which uses social marketing methods, is headed by Stewart Parkinson from the UK. His previous experience has been in the private sector; he has worked in sales, marketing, and advertising for companies like Coca Cola, Budweiser, Securicor, and Mates. "Social marketing," he says, "is simply getting people to buy a product". He sees no clash with more conventional health education practitioners, believing that the two approaches can complement each other. "Much of the work simply involves pointing out the benefits of condoms," says Parkinson. "You can convert large numbers of people to the idea in a short space of time if you get the message right]" Nevertheless, as he points out, the conversion rate usually drops after that. "At first the take-up is from middle-income people, who already have a latent demand for condoms. The poor are harder to reach." He says Nigeria is a very suitable country for a private sector approach to condom promotion, as there is no functioning public sector. He recently paid a visit to Zimbabwe, where the public sector is strong, and agrees that different approaches may be suitable there. The scheme provided 85% of the 65 million condoms used in Nigeria last year. Stewart Parkinson says, "It's working out at only US$5 to provide protection for one couple per year--a very cheap intervention]" full text

Interaction of ions, atoms, and small molecules with quantized vortex lines in superfluid (4)He.

PubMed

Mateo, David; Eloranta, Jussi; Williams, Gary A

2015-02-14

The interaction of a number of impurities (H2, Ag, Cu, Ag2, Cu2, Li, He3 (+), He(*) ((3)S), He2 (∗) ((3)Σu), and e(-)) with quantized rectilinear vortex lines in superfluid (4)He is calculated by using the Orsay-Trento density functional theory (DFT) method at 0 K. The Donnelly-Parks (DP) potential function binding ions to the vortex is combined with DFT data, yielding the impurity radius as well as the vortex line core parameter. The vortex core parameter at 0 K (0.74 Å) obtained either directly from the vortex line geometry or through the DP potential fitting is smaller than previously suggested but is compatible with the value obtained from re-analysis of the Rayfield-Reif experiment. All of the impurities have significantly higher binding energies to vortex lines below 1 K than the available thermal energy, where the thermally assisted escape process becomes exponentially negligible. Even at higher temperatures 1.5-2.0 K, the trapping times for larger metal clusters are sufficiently long that the previously observed metal nanowire assembly in superfluid helium can take place at vortex lines. The binding energy of the electron bubble is predicted to decrease as a function of both temperature and pressure, which allows adjusting the trap depth for either permanent trapping or to allow thermally assisted escape. Finally, a new scheme for determining the trapping of impurities on vortex lines by optical absorption spectroscopy is outlined and demonstrated for He(*).

Hemodialysis Reliable Outflow (HeRO) device in end-stage dialysis access: a decision analysis model.

PubMed

Dageforde, Leigh Anne; Bream, Peter R; Moore, Derek E

2012-09-01

The Hemodialysis Reliable Outflow (HeRO) dialysis access device is a permanent tunneled dialysis graft connected to a central venous catheter and is used in patients with end-stage dialysis access (ESDA) issues secondary to central venous stenosis. The safety and effectiveness of the HeRO device has previously been proven, but no study thus far has compared the cost of its use with tunneled dialysis catheters (TDCs) and thigh grafts in patients with ESDA. A decision analytic model was developed to simulate outcomes for patients with ESDA undergoing placement of a HeRO dialysis access device, TDC, or thigh graft. Outcomes of interest were infection, thrombosis, and ischemic events. Baseline values, ranges, and costs were determined from a systematic review of the literature. Total costs were based on 1 year of post-procedure outcomes. Sensitivity analyses were conducted to test model strength. The HeRO dialysis access device is the least costly dialysis access with an average 1-year cost of $6521. The 1-year cost for a TDC was $8477. A thigh graft accounted for $9567 in a 1-year time period. The HeRO dialysis access device is the least costly method of ESDA. The primary determinants of cost in this model are infection in TDCs and leg ischemia necessitating amputation in thigh grafts. Further study is necessary to incorporate patient preference and quality of life into the model. Copyright © 2012 Elsevier Inc. All rights reserved.

Interaction of ions, atoms, and small molecules with quantized vortex lines in superfluid 4He

NASA Astrophysics Data System (ADS)

Mateo, David; Eloranta, Jussi; Williams, Gary A.

2015-02-01

The interaction of a number of impurities (H2, Ag, Cu, Ag2, Cu2, Li, He3 + , He* (3S), He2∗ (3Σu), and e-) with quantized rectilinear vortex lines in superfluid 4He is calculated by using the Orsay-Trento density functional theory (DFT) method at 0 K. The Donnelly-Parks (DP) potential function binding ions to the vortex is combined with DFT data, yielding the impurity radius as well as the vortex line core parameter. The vortex core parameter at 0 K (0.74 Å) obtained either directly from the vortex line geometry or through the DP potential fitting is smaller than previously suggested but is compatible with the value obtained from re-analysis of the Rayfield-Reif experiment. All of the impurities have significantly higher binding energies to vortex lines below 1 K than the available thermal energy, where the thermally assisted escape process becomes exponentially negligible. Even at higher temperatures 1.5-2.0 K, the trapping times for larger metal clusters are sufficiently long that the previously observed metal nanowire assembly in superfluid helium can take place at vortex lines. The binding energy of the electron bubble is predicted to decrease as a function of both temperature and pressure, which allows adjusting the trap depth for either permanent trapping or to allow thermally assisted escape. Finally, a new scheme for determining the trapping of impurities on vortex lines by optical absorption spectroscopy is outlined and demonstrated for He*.

Review of Medicinal Remedies on Hand Eczema Based on Iranian Traditional Medicine: A Narrative Review Article

PubMed Central

MANSOURI, Parvin; KHADEMI, Aleme; PAHLEVAN, Daryoush; MEMARIANI, Zahra; ALIASL, Jale; SHIRBEIGII, Laila

2016-01-01

Background: Hand Eczema (HE) is a dermatological disorder with frequent relapses and multiple causes such as atopic, allergic and irritant contact dermatitis. The management is complex because of the wide range of different pathogenesis. Efficacy of some of available treatments is not well established and it can affect patients’ quality of life significantly. Methods: Reports on HE such as diagnosis, pathophysiology, pharmacological and nonpharmacological therapy that described in medieval Iranian medicine, were gathered and analyzed from selected medical and pharmaceutical textbooks of Iranian Traditional Medicine (ITM). The search of databases such as PubMed, EMBASE/Excerpta Medica, Science direct, Scopus, Google scholar, Web of science, Sid, Iran medex, Irandoc, was performed to reconfirm the efficacy of ITM remedies in conventional medicine from 1980-Jan-1 to 2015-Dec-30. Results: According to their opinion, HE is highly associated with liver function. This disorder was categorized into two main types as wet and dry ones. Most Iranian textbook explained signs of HE, as excessive skin itching, redness, burning and dryness. Treatments recommended by Iranian scientists were lifestyle modification, dietary intervention and performing the rules of prevention as well as herbal therapy and special manipulations. Conclusion: Iranian practitioners believed that, six essential principles, diet therapy and medicinal plants have high impact on treatment of HE. These remedies based on Iranian scholar’s experiences might be useful for further studies to the management of HE. PMID:27928524

Norman Stuart heaps 1928”1986

NASA Astrophysics Data System (ADS)

Cartwright, David E.

Dr. Norman Heaps died on June 26, 1986, in a hospital near his native town of Prescot, U.K., a suburb of Liverpool, after a long illness punctuated by bouts of painful medical treatment for lung cancer. He was the pioneer in Britain of the numerical modeling of tides and storm surges in shelf seas.He graduated at the University of Liverpool in 1949 with honors in mathematics with subsidiary physics and oceanography. Many years later the same university awarded him a doctorate on the basis of his published work. Norman's first 10 postgraduate years were spent as mathematician in the aircraft industry, but he never felt at home in the industrial world and sought a more academic career. While lecturing at the Royal College of Advanced Technology at Salford, Manchester (now the University of Salford), he struck a lasting friendship with Clifford Mortimer, FRS, then director of the Freshwater Biological Association laboratory at Lake Windermere, who first interested Heaps in the problem of computing the natural seiche oscillations of that lake. The use of electronic computers was still in its infancy, but Heaps saw that the equations of internal oscillations in such a lake could be solved numerically by methods that he had developed in the theory of wing structures. Heaps worked up a Master's thesis on this problem during his summer vacations, and he later worked with Mortimer at the University of Wisconsin on a more advanced scheme involving the coupled oscillations of Green Bay and Lake Michigan.

Dr. Karol de Beaurain - a psychiatrist's profile. Part 2.

PubMed

Rutkowski, Krzysztof; Dembińska, Edyta

2017-06-18

The paper sets out to recall the profile of Karol de Beaurain, a psychiatrist, who was one of first Poles to use the psychoanalytic method in treatment. So far, he has been mostly known as the one who was Witkacy's psychoanalyst. Stanisław Ignacy Witkiewicz and Eugenia Dunin-Borkowska are the first patients who are known by their names and who received psychoanalytic treatment in the history of the Polish medicine. Stanisław Ignacy Witkiewicz's letters and drawings originating from the psychoanalysis period served as a source of information about Witkacy's psychoanalysis. The paper illustrates dr Beaurain's fate during World War I when he was first a military doctor in Skoczów and then an assistant in prof. Piltz's Neurological-Psychiatric Clinic in Kraków where he actively participated in the creation of a multidimensional programme of war neurosis treatment. After the war finished, initially Beaurain stayed at his assistant post at the Psychiatric Clinic in Kraków but then in 1921 he relocated to the National Psychiatric Hospital in Dziekanka near Poznań. With his professional expertise he contributed to the strengthening of the Great Poland region psychiatry that had experienced qualified personnel shortages after the German qualified staff left. The growing numbers of patients and the overload of professional duties were probably the factors that led to dr. Beaurain's premature death while he was holding the position of the head physician at the National Psychiatric Hospital in Owińska in February 1927.

Auguste Forel on ants and neurology.

PubMed

Parent, André

2003-08-01

Auguste Forel was born in 1848 in the French part of Switzerland. He developed a lifelong passion for myrmecology in his childhood, but chose medicine and neuropsychiatry to earn his living. He first undertook a comparative study of the thalamus under Theodor Meynert in Vienna and then, from 1872 to 1879, he worked as Assistant Physician to Bernhard von Gudden in Munich. This led in 1877 to his seminal work on the organization of the tegmental region in which he provides the first description of the zona incerta and the so-called H (Haubenfeld) fields that still bear his name. In 1879, Forel was appointed Professor of Psychiatry in Munich and Director of the Burghölzli cantonal asylum. He became interested in the therapeutic value of hypnotism, while continuing his work on brain anatomy and ants. His neuroanatomical studies with Gudden's method led him to formulate the neuron theory in 1887, four years before Wilhelm von Waldeyer, who received most of the credit for it. Forel then definitively turned his back on neuroscience. After his retirement from the Burghölzli asylum in 1898. and despite a stroke in 1911 that left him hemiplegic, Forel started to write extensively on various social issues, such as alcohol abstinence and sexual problems. Before his death in 1931 at the age of 83, Forel published a remarkable book on the social world of the ants in which he made insightful observations on the neural control of sensory and instinctive behavior common to both humans and insects.

On the reconciliation of missing heritability for genome-wide association studies

PubMed Central

Chen, Guo-Bo

2016-01-01

The definition of heritability has been unique and clear, but its estimation and estimates vary across studies. Linear mixed model (LMM) and Haseman–Elston (HE) regression analyses are commonly used for estimating heritability from genome-wide association data. This study provides an analytical resolution that can be used to reconcile the differences between LMM and HE in the estimation of heritability given the genetic architecture, which is responsible for these differences. The genetic architecture was classified into three forms via thought experiments: (i) coupling genetic architecture that the quantitative trait loci (QTLs) in the linkage disequilibrium (LD) had a positive covariance; (ii) repulsion genetic architecture that the QTLs in the LD had a negative covariance; (iii) and neutral genetic architecture that the QTLs in the LD had a covariance with a summation of zero. The neutral genetic architecture is so far most embraced, whereas the coupling and the repulsion genetic architecture have not been well investigated. For a quantitative trait under the coupling genetic architecture, HE overestimated the heritability and LMM underestimated the heritability; under the repulsion genetic architecture, HE underestimated but LMM overestimated the heritability for a quantitative trait. These two methods gave identical results under the neutral genetic architecture. A general analytical result for the statistic estimated under HE is given regardless of genetic architecture. In contrast, the performance of LMM remained elusive, such as further depended on the ratio between the sample size and the number of markers, but LMM converged to HE with increased sample size. PMID:27436266