Recent advances in X-ray microanalysis in dermatology

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

Forslind, B.; Grundin, T.G.; Lindberg, M.

1985-01-01

Electron microprobe and proton microprobe X-ray analysis can be used in several areas of dermatological research. With a proton probe, the distribution of trace elements in human hair can be determined. Electron microprobe analysis on freeze-dried cryosections of guinea-pig and human epidermis shows a marked gradient of Na, P and K over the stratum granulosum. In sections of freeze-substituted human skin this gradient is less steep. This difference is likely to be due to a decrease in water content of the epidermis towards the stratum corneum. Electron microprobe analysis of the epidermis can, for analysis of trace elements, be complementedmore » by the proton microprobe. Quantitative agreement between the two techniques can be obtained by the use of a standard. Proton microprobe analysis was used to determine the distribution of Ni or Cr in human epidermis exposed to nickel or chromate ions. Possible differences in water content between the stratum corneum of patients with atopic eczema and normal stratum corneum was investigated in skin freeze-substituted with Br-doped resin. No significant differences were observed.« less

Preliminary mineralogical data on epithermal ore veins associated with Rosia Poieni porphyry copper deposit, Apuseni Mountains, Romania

NASA Astrophysics Data System (ADS)

Iatan, E. L.; Popescu, Gh. C.

2012-04-01

Rosia Poieni is the largest porphyry copper (±Au±Mo) deposits associated with Neogene magmatic rocks from the South Apuseni Mountains, being located approximately 8 km northeast of the town of Abrud. During a recent examination of some epithermal mineralized veins, crosscutting the porphyry mineralization from the Roşia Poieni deposit, two species of tellurides and one tellurosulfide minerals were identified. The studied samples were collected from the + 1045 m level, SW side of the open pit and are represented by epithermal veins, crosscutting the porphyry copper mineralized body. The thickness of the veins is almost 4 cm. Following reflected-polarized light microscopy to identify the ore-mineral assemblages, the polished sections were studied with a Scanning Electron Microscope (SEM) equipped with a back-scattered electron (BSE) detector to study fine-sized minerals. Quantitative compositional data were determined using a Cameca SX 50 electron microprobe (EMP). Based on optical microscopy, SEM and EMPA three mineral associations have been separated inside the epithermal vein, from the margins to the centre: 1. quartz+tennantite-tetrahedrite+goldfieldite+pyrite+sphalerite; 2. quartz+pyrite+tellurobismutite; 3. chalcopyrite+hessite+vivianite. Goldfieldite occurs in anhedral grains and it is associated with tennantite-tetrahedrite and quartz. The electron microprobe analysis gave a variable content in Te between 13.28-13.39 wt.%, 43.34 wt.% Cu, 0.1 wt. % Fe, 0.2 wt.% Zn, 14.68 wt.% As, 4.35 wt.% Sb and 24.84 wt.% S. The calculated formula for the goldfieldite is Cu11.8Te1.8(Sb,As)4S13.4. The EPM analyses on tetrahedrite-tennantite revealed a low content in Te (0.02-0.03 wt.%) and 42.23 wt.% Cu, 2.67 wt.% Fe, 7.34 wt.% Zn, 0.04 wt.% Sb, 19.28 wt.% As and 28.4 wt.% S. The calculated formula is Cu9.8(Fe,Zn)2.4(Sb,As,Te)3.8S13. The variable ratio of the Te content may reflect a variable content of Te in the hydrothermal fluids from which the tellurian tetrahedrite precipitated. Hessite lies close to the grain boundary between the calchopyrite grains, which is associated with vivianite. Electron microprobe analysis gave 57.73 wt.% Ag and 42.27 wt.% Te with calculated stoichiometric formula Ag1.9Te1.1 . Tellurobismuthite it forms irregular grains and it is associated with quartz and pyrite. Electron microprobe analysis gave 57.20 wt.% Bi and 42.80 wt.% Te with calculated stoichiometric formula Bi2.2Te2.8. Based on the mineral assemblages separated inside the ore vein and on the ratio of the Te content for the different identified tellurium bearing minerals, we can conclude that the Te content of the fluids from which they precipitated, increased from the margins to the centre of the vein. In summary, this study of specimens from Rosia Poieni porphyry copper deposit, has resulted in the recognition of some tellurium-bearing minerals, not reported by previous workers. These minerals are represented by tellurobismutite, hessite and goldfieldite and they are associated with epithermal vein mineralization (pyrite, chalcopyrite, sphalerite, tennantite-tetrahedrite, quartz, vivianite). The presence of tellurium indicates the transition between porphyry-style mineralization to epithermal vein mineralization. Acknowledgements: This work was supported by the strategic grant POSDRU/89/1.5/S58852, Project "Postdoctoral program for training scientific researches" co-financed by the European Social Found within the Sectorial Operational Program Human Resources Development 2007-2013".

Nuclear Electromagnetic Pulse Review

NASA Astrophysics Data System (ADS)

Dinallo, Michael

2011-04-01

Electromagnetic Pulse (EMP) from nuclear detonations have been observed for well over half a century. Beginning in the mid-to-late 1950s, the physics and modeling of EMP has been researched and will continue into the foreseeable future. The EMP environment propagates hundreds of miles from its origins and causes interference for all types of electronic instrumentation. This includes military, municipal and industry based electronic infrastructures such as power generation and distribution, command and control systems, systems used in financial and emergency services, electronic monitoring and communications networks, to mention some key infrastructure elements. Research into EMP has included originating physics, propagation and electromagnetic field coupling analyses and measurement-sensor development. Several methods for calculating EMP induced transient interference (voltage and current induction) will be briefly discussed and protection techniques reviewed. These methods can be mathematically simple or involve challenging boundary value solution techniques. A few illustrative calculations will demonstrate the concern for electronic system operability. Analyses such as the Wunsch-Bell model for electronic upset or damage, and the Singularity Expansion Method (SEM) put forth by Dr. Carl Baum, will facilitate the concern for EMP effects. The SEM determines the voltages and currents induced from transient electromagnetic fields in terms of natural modes of various types of electronic platforms (aerospace vehicles or land-based assets - fixed or mobile). Full-scale facility and laboratory simulation and response measurement approaches will be discussed. The talk will conclude with a discussion of some present research activities.

Generation and detection of edge magnetoplasmons in a quantum Hall system using a photoconductive switch

NASA Astrophysics Data System (ADS)

Lin, Chaojing; Morita, Kyosuke; Muraki, Koji; Fujisawa, Toshimasa

2018-04-01

Edge magnetoplasmons (EMPs) are unidirectional charge density waves travelling in an edge channel of a two-dimensional electron gas in the quantum Hall regime. We present both generation and detection schemes with a photoconductive switch (PCS) for EMPs. Here, the conductance of the PCS is modulated by irradiation with a laser beam, whose amplitude can be modulated by an external signal. When the PCS is used as a generator, the electrical current from the PCS is injected into the edge channel to excite EMPs. When the PCS is used as a detector, the electronic potential induced by EMPs is applied to the PCS with a modulated laser beam so as to constitute a phase-sensitive measurement. For both experiments, we confirm that the time of flight for the EMPs increases with the magnetic field in agreement with the EMP characteristics. Combination of the two schemes would be useful in investigating and utilizing EMPs at higher frequencies.

Electron microprobe mineral analysis guide

NASA Technical Reports Server (NTRS)

Brown, R. W.

1980-01-01

Electron microprobe mineral analysis guide is a compilation of X-ray tables and spectra recorded from various mineral matrices. Spectra were obtained using electron microprobe, equipped with LiF geared, curved crystal X-ray spectrometers, utilizing typical analytical operating conditions: 15 Kv acceleration potential, 0.02 microampere sample current as measured on a clinopyroxene standard (CP19). Tables and spectra are presented for the majority of elements, fluorine through uranium, occurring in mineral samples from lunar, meteoritic and terrestrial sources. Tables for each element contain relevant analytical information, i.e., analyzing crystal, X-ray peak, background and relative intensity information, X-ray interferences and a section containing notes on the measurement. Originally intended to cover silicates and oxide minerals the tables and spectra have been expanded to cover other mineral phases. Electron microprobe mineral analysis guide is intended as a spectral base to which additional spectra can be added as the analyst encounters new mineral matrices.

Advanced characterization of glass/melt inclusions trapped in phenocrysts by combined SEM-EDS, EMP-WDS and FT-IR techniques

NASA Astrophysics Data System (ADS)

Bellatreccia, Fabio; Cavallo, Andrea; de Astis, Gianfilippo; Della Ventura, Giancarlo; Mangiacapra, Annarita; Moretti, Roberto; Mormone, Angela; Piochi, Monica

2010-05-01

Melt inclusions (MIs) are micrometric-sized and variable-shaped impurity parcels of glass ± vesicles ± solids present within cavities or fractures of crystals. Because representing melt droplets that were trapped during crystal growth, they are believed to record the variable physico-chemical conditions of the hosting multi-phase system. Therefore, MIs are unique probe of near-liquidus magmatic conditions, otherwise inaccessible to Earth Scientists, and are widely used to integrate and corroborate conventional petrological and volcanological techniques based on mineral phases and whole rocks. Electron microprobe (EMP-WDS) and microscopy (SEM-EDS), and Fourier Transform Infra Red (FT-IR) spectroscopy are well-established analytical techniques, commonly used to determine composition of the magma from which MIs formed. Noteworthy, FT-IR is usually adopted to determine the content of dissolved H2O and CO2, providing i) essential information for entrapment pressures, hence depths of crystal growth, and ii) constraints to the volatile budget of magmas. Assessing such volatile contents has significant implications for the understanding of magma evolution and migration, from the depths of parental magma genesis, through the main depths of crustal storage, up to surface. The MI-based quantification of volatile contents and the recognition of degassing patterns are also vital for deciphering magma rheology, which largely affects eruptive dynamics and style. Limits to melt inclusion studies are i) their typically very small size (< 100 µm), ii) the possible late and secondary crystallization, iii) the diffusivity-driven chemical exchange between melt and host crystal, iv) and the alteration phenomena that mask or even delete the original melt composition. Here, we present a study of glass/melt inclusions in phenocrysts from Procida Island (Phlegraean Volcanic District, South Italy), analyzed for combined SEM-EDS electron microscopy, EMP-WDS microchemistry and FT-IR spectroscopy. In particular, we have characterized the distribution of volatile H and C species across both the host crystals and the inclusions, by using a focal-plane-array (FPA) of detectors. The FPA technique allows the acquisition of a large number of IR spectra simultaneously and generate mid-IR images with high resolving power of the target molecules in the H-O-C system. The integration of these analytical techniques is a mandatory step in order to provide definite advances in MI characterization and data interpretation.

Examination of Surveyor 3 parts with the scanning electron microscope and electron microprobe

NASA Technical Reports Server (NTRS)

Chodos, A. A.; Devaney, J. R.; Evens, K. C.

1972-01-01

Two screws and two washers, several small chips of tubing, and a fiber removed from a third screw were examined with the scanning electron microscope and the electron microprobe. The purpose of the examination was to determine the nature of the material on the surface of these samples and to search for the presence of meteoritic material.

Correlated petrographic, electron microprobe, and ion microprobe studies of selected primitive and processed phase assemblages in meteorites

NASA Technical Reports Server (NTRS)

Albee, Arden L.

1993-01-01

During the past three years we have received support to continue our research in elucidating the formation and alteration histories of selected meteoritic materials by a combination of petrographic, trace element, and isotopic analyses employing optical and scanning electron microscopes and electron and ion microprobes. The awarded research funds enabled the P.I. to attend the annual LPSC, the co-I to devote approximately 15 percent of his time to the research proposed in the grant, and partial support for a visiting summer post-doctoral fellow to conduct electron microprobe analyses of meteoritic samples in our laboratory. The research funds, along with support from the NASA Education Initiative awarded to P.I. G. Wasserburg, enabled the co-I to continue a mentoring program with inner-city minority youth. The support enabled us to achieve significant results in the five projects that we proposed (in addition to the Education Initiative), namely: studies of the accretional and post-accretional alteration and thermal histories in CV meteorites, characterization of periclase-bearing Fremdlinge in CV meteorites, characterization of Ni-Pt-Ge-Te-rich Fremdlinge in CV meteorites in an attempt to determine the constraints they place on the petrogenetic and thermal histories of their host CAI's, correlated electron and ion microprobe studies of silicate and phosphate inclusions in the Colomera meteorite in an attempt to determine the petrogenesis of the IE iron meteorites, and development of improved instrumental and correction procedures for improved accuracy of analysis of meteoritic materials with the electron microprobe. This grant supported, in part or whole, 18 publications so far by our research team, with at least three more papers anticipated. The list of these publications is included. The details of the research results are briefly summarized.

The relationship between various exposure metrics for elongate mineral particles (EMP) in the taconite mining and processing industry.

PubMed

Hwang, Jooyeon; Ramachandran, Gurumurthy; Raynor, Peter C; Alexander, Bruce H; Mandel, Jeffrey H

2014-01-01

Different dimensions of elongate mineral particles (EMP) have been proposed as being relevant to respiratory health end-points such as mesothelioma and lung cancer. In this article, a methodology for converting personal EMP exposures measured using the National Institute for Occupational Safety and Health (NIOSH) 7400/7402 methods to exposures based on other size-based definitions has been proposed and illustrated. Area monitoring for EMP in the taconite mines in Minnesota's Mesabi Iron Range was conducted using a Micro Orifice Uniform Deposit Impactor (MOUDI) size-fractionating sampler. EMP on stages of the MOUDI were counted and sized according to each EMP definition using an indirect-transfer transmission electron microscopy (ISO Method 13794). EMP were identified using energy-dispersive x-ray and electron diffraction analysis. Conversion factors between the EMP counts based on different definitions were estimated using (1) a linear regression model across all locations and (2) a location-specific ratio of the count based on each EMP definition to the NIOSH 7400/7402 count. The highest fractions of EMP concentrations were found for EMP that were 1-3 μm in length and 0.2-0.5 μm in width. Therefore, the current standard NIOSH Method 7400, which only counts EMP >5 μm in length and ≥ 3 in aspect ratio, may underestimate amphibole EMP exposures. At the same time, there was a high degree of correlation between the exposures estimated according to the different size-based metrics. Therefore, the various dimensional definitions probably do not result in different dose-response relationships in epidemiological analyses. Given the high degree of correlation between the various metrics, a result consistent with prior research, a more reasonable metric might be the measurement of all EMP irrespective of size. [Supplementary materials are available for this article. Go to the publisher's online edition of Journal of Occupational and Environmental Hygiene for the following free supplemental resource: figures detailing EMP concentration.].

Electromagnetic pulse reduces free radical generation in rat liver mitochondria in vitro.

PubMed

Wang, C; Zhou, H; Peng, R; Wang, L; Su, Z; Chen, P; Wang, S; Wang, S; Liu, Y; Cong, J; Wu, K; Hu, X; Fan, E

2013-04-01

Non-ionizing radiation electromagnetic pulse (EMP) is generally recorded to induce the generation of free radicals in vivo. Though mitochondria are the primary site to produce free radicals, a rare report is designed to directly investigate the EMP effects on free radical generation at mitochondrial level. Thus the present work was designed to study how EMP induces free radical generation in rat liver mitochondria in vitro using electron paramagnetic resonance technique. Surprisingly, our data suggest that EMP prevents free radical generation by activating antioxidant enzyme activity and reducing oxygen consumption and therefore free radical generation. Electron spin resonance measurements clearly demonstrate that disordering of mitochondrial lipid fluidity and membrane proteins mobility are the underlying contributors to this decreased oxygen consumption. Therefore, our results suggest that EMP might hold the potentiality to be developed as a non-invasive means to benefit certain diseases.

Ultrashort laser pulses and electromagnetic pulse generation in air and on dielectric surfaces.

PubMed

Sprangle, P; Peñano, J R; Hafizi, B; Kapetanakos, C A

2004-06-01

Intense, ultrashort laser pulses propagating in the atmosphere have been observed to emit sub-THz electromagnetic pulses (EMPS). The purpose of this paper is to analyze EMP generation from the interaction of ultrashort laser pulses with air and with dielectric surfaces and to determine the efficiency of conversion of laser energy to EMP energy. In our self-consistent model the laser pulse partially ionizes the medium, forms a plasma filament, and through the ponderomotive forces associated with the laser pulse, drives plasma currents which are the source of the EMP. The propagating laser pulse evolves under the influence of diffraction, Kerr focusing, plasma defocusing, and energy depletion due to electron collisions and ionization. Collective effects and recombination processes are also included in the model. The duration of the EMP in air, at a fixed point, is found to be a few hundred femtoseconds, i.e., on the order of the laser pulse duration plus the electron collision time. For steady state laser pulse propagation the flux of EMP energy is nonradiative and axially directed. Radiative EMP energy is present only for nonsteady state or transient laser pulse propagation. The analysis also considers the generation of EMP on the surface of a dielectric on which an ultrashort laser pulse is incident. For typical laser parameters, the power and energy conversion efficiency from laser radiation to EMP radiation in both air and from dielectric surfaces is found to be extremely small, < 10(-8). Results of full-scale, self-consistent, numerical simulations of atmospheric and dielectric surface EMP generation are presented. A recent experiment on atmospheric EMP generation is also simulated.

Tephrochronology and Stratigraphy of Silicic and Basaltic Volcanic Ash Layers at Hagerman Fossil Beds National Monument, Idaho, USA

NASA Astrophysics Data System (ADS)

Walkup, L. C.; Prassack, K. A.; Hart, W. K.; Wan, E.

2016-12-01

Hagerman Fossil Beds National Monument (HAFO) is home to a diverse early-middle Pliocene ( 4.2-3.0 Ma) faunal assemblage. The Glenns Ferry Formation, exposed within the Monument and in surrounding areas, preserves lacustrine and fluvial deposits interbedded with tephra and lava flows establishing a broad chronostratigraphic context for the fossils. Despite multiple attempts by previous studies to date several volcanic horizons within the Glenns Ferry Formation, the precise chronostratigraphy of specific key fossil localities within the Monument remains poorly constrained. HAFO contains many type specimens, including that of the newly described river otter Lontra weiri (Prassack, 2016). The chronologies of type specimens are especially important because they establish the first and, in some cases, only known occurrence of a species in the fossil record. Refined chronology also allows for community-level reconstructions of fauna across ancient landscapes. Thus, multiple silicic and basaltic tephra distributions were mapped, sampled, petrographically characterized, analyzed by electron microprobe (EMP), and correlated across the Monument to provide a refined spatial and temporal framework for specific fossil localities. Previous tephrochronologic studies focused on the Fossil Gulch and Peters Gulch areas. This investigation extends the mapped distribution extent of the tephra layers identified by other workers. To further support the updated tephrochronologic framework, several tephra samples from type localities were also analyzed using EMP and correlated with samples collected during this study. We also present a new age of 3.07± 0.23 Ma for an upper tephra horizon, measured via ITPFT and DCFT glass fission track methods. This age is in agreement with a previously suggested age of 3.15 Ma for this horizon based on regional tephra correlation and more precisely constrains the age of an important underlying fossil site.

Core Community Specifications for Electron Microprobe Operating Systems: Software, Quality Control, and Data Management Issues

NASA Technical Reports Server (NTRS)

Fournelle, John; Carpenter, Paul

2006-01-01

Modem electron microprobe systems have become increasingly sophisticated. These systems utilize either UNIX or PC computer systems for measurement, automation, and data reduction. These systems have undergone major improvements in processing, storage, display, and communications, due to increased capabilities of hardware and software. Instrument specifications are typically utilized at the time of purchase and concentrate on hardware performance. The microanalysis community includes analysts, researchers, software developers, and manufacturers, who could benefit from exchange of ideas and the ultimate development of core community specifications (CCS) for hardware and software components of microprobe instrumentation and operating systems.

The Staphylococcus aureus extracellular matrix protein (Emp) has a fibrous structure and binds to different extracellular matrices.

PubMed

Geraci, Jennifer; Neubauer, Svetlana; Pöllath, Christine; Hansen, Uwe; Rizzo, Fabio; Krafft, Christoph; Westermann, Martin; Hussain, Muzaffar; Peters, Georg; Pletz, Mathias W; Löffler, Bettina; Makarewicz, Oliwia; Tuchscherr, Lorena

2017-10-20

The extracellular matrix protein Emp of Staphylococcus aureus is a secreted adhesin that mediates interactions between the bacterial surface and extracellular host structures. However, its structure and role in staphylococcal pathogenesis remain unknown. Using multidisciplinary approaches, including circular dichroism (CD) and Fourier transform infrared (FTIR) spectroscopy, transmission electron (TEM) and immunogold transmission electron microscopy, functional ELISA assays and in silico techniques, we characterized the Emp protein. We demonstrated that Emp and its truncated forms bind to suprastructures in human skin, cartilage or bone, among which binding activity seems to be higher for skin compounds. The binding domain is located in the C-terminal part of the protein. CD spectroscopy revealed high contents of β-sheets (39.58%) and natively disordered structures (41.2%), and TEM suggested a fibrous structure consisting of Emp polymers. The N-terminus seems to be essential for polymerization. Due to the uncommonly high histidine content, we suggest that Emp represents a novel type of histidine-rich protein sharing structural similarities to leucine-rich repeats proteins as predicted by the I-TASSER algorithm. These new findings suggest a role of Emp in infections of deeper tissue and open new possibilities for the development of novel therapeutic strategies.

Determination of nitrogen in coal macerals using electron microprobe technique-experimental procedure

USGS Publications Warehouse

Mastalerz, Maria; Gurba, L.W.

2001-01-01

This paper discusses nitrogen determination with the Cameca SX50 electron microprobe using PCO as an analyzing crystal. A set of conditions using differing accelerating voltages, beam currents, beam sizes, and counting times were tested to determine parameters that would give the most reliable nitrogen determination. The results suggest that, for the instrumentation used, 10 kV, current 20 nA, and a counting time of 20 s provides the most reliable nitrogen determination, with a much lower detection limit than the typical concentration of this element in coal. The study demonstrates that the electron microprobe technique can be used to determine the nitrogen content of coal macerals successfully and accurately. ?? 2001 Elsevier Science B.V. All rights reserved.

PROTON MICROPROBE ANALYSIS OF TRACE-ELEMENT VARIATIONS IN VITRINITES IN THE SAME AND DIFFERENT COAL BEDS.

USGS Publications Warehouse

Minkin, J.A.; Chao, E.C.T.; Blank, Herma; Dulong, F.T.

1987-01-01

The PIXE (proton-induced X-ray emission) microprobe can be used for nondestructive, in-situ analyses of areas as small as those analyzed by the electron microprobe, and has a sensitivity of detection as much as two orders of magnitude better than the electron microprobe. Preliminary studies demonstrated that PIXE provides a capability for quantitative determination of elemental concentrations in individual coal maceral grains with a detection limit of 1-10 ppm for most elements analyzed. Encouraged by the earlier results, we carried out the analyses reported below to examine trace element variations laterally (over a km range) as well as vertically (cm to m) in the I and J coal beds in the Upper Cretaceous Ferron Sandstone Member of the Mancos Shale in central Utah, and to compare the data with the data from two samples of eastern coals of Pennsylvanian age.

Effects of Electromagnetic Pulses on a Multilayered System

DTIC Science & Technology

2014-07-01

repeatable high - power generators . Repetitive EMP (REMP) is usually wideband with each pulse being composed of a wide range of frequencies. This larger...types of EMPs that are of concern regarding electronics and system infrastructures; they are high -altitude EMP (HEMP) generated from nuclear...ELECTROMAGNETIC PULSES ON A MULTILAYERED SYSTEM A. Upia, K. M. Burke, J. L. Zirnheld Energy Systems Institute, Department of Electrical Engineering

Wavelength dispersive analysis with the synchrotron x ray fluorescence microprobe

NASA Technical Reports Server (NTRS)

Rivers, M. L.; Thorn, K. S.; Sutton, S. R.; Jones, K. W.; Bajt, S.

1993-01-01

A wavelength dispersive spectrometer (WDS) was tested on the synchrotron x ray fluorescence microprobe at Brookhaven National Laboratory. Compared to WDS spectra using an electron microprobe, the synchrotron WDS spectra have much better sensitivity and, due to the absence of bremsstrahlung radiation, lower backgrounds. The WDS spectrometer was successfully used to resolve REE L fluorescence spectra from standard glasses and transition metal K fluorescence spectra from kamacite.

Mushrooming vulnerability to EMP

NASA Astrophysics Data System (ADS)

Lerner, E. J.

1984-08-01

The electromagnetic pulse (EMP) generated by a single thermonuclear bomb detonated above the continental U.S. could set up electrical fields of 50 kV/m over nearly all of North America. Since the progressively microminiaturized integrated circuits of current military and civilian electronics become more vulnerable with decreasing circuit element size, even shield-protected chips can now be destroyed by the substantially shield-dampened EMP pulses. It is noted as a source of special concern that, as nuclear weapons have evolved, the EMP characteristically generated by them has shifted to increasingly shorter wavelengths, requiring significant redesign of EMP shields devised a decade or more ago. The surge arresters currently employed may not react sufficiently rapidly for existing weapons.

Ilmenite exsolution schemes in Apollo-17 high-Ti basalts

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

Vaniman, D.; Heiken, G.; Muhich, T.

1990-01-01

Combined electron microprobe and scanning electron microscope (SEM) x-ray image analyses are used to obtain semiquantitative data on the relations between ilmenite grains and their exsolved chromite and rutile. Comparisons of these data for ilmenites in four Apollo-17 high-Ti basalts with a database of electron microprobe analyses from the literature indicates that Cr expulsion from ilmenite can be as important as Fe{sup 2+} reduction in causing subsolidus exsolution of chromite and rutile from ilmenite. 12 refs., 4 figs., 5 tabs.

Electron microprobe study of lunar and planetary zoned plagioclase feldspars: An analytical and experimental study of zoning in plagioclase

NASA Technical Reports Server (NTRS)

Smith, R. K.; Lofgren, G. E.

1982-01-01

Natural and experimentally grown zoned plagioclase feldspars were examined by electron microprobe. The analyses revealed discontinuous, sector, and oscillary chemical zoning superimposed on continuous normal or reverse zoning trends. Postulated mechanisms for the origin of zoning are based on either physical changes external to the magma (P, T, H2O saturation) or kinetic changes internal to the magma (diffusion, supersaturation, growth rate). Comparison of microprobe data on natural zoned plagioclase with zoned plagioclase grown in controlled experiments show that it may be possible to distinguish zonal development resulting from physio-chemical changes to the bulk magma from local kinetic control on the growth of individual crystals.

Nuclear pulse. I - Awakening to the chaos factor

NASA Astrophysics Data System (ADS)

Broad, W. J.

1981-05-01

The discovery of the significance of the high-voltage wave termed electromagnetic pulse (EMP), which occurs following the high-altitude detonation of a nuclear device, is discussed. The disruptions to the street lights, burglar alarms and circuit breakers of Hawaii caused by the detonation of a nuclear device 248 mi above Johnson Island in the Pacific in July, 1962 are described and attributed to the Compton electrons produced by the impact of gamma rays from the nuclear explosion on air in the upper atmosphere. It is pointed out, however, that at the time of the explosion, most communications systems were based on vacuum tube and electromechanical technology, which is about 10,000,000 times harder against EMP than integrated solid-state circuitry, and thus the threat posed by EMP to the power grid and communications capabilities was not apparent. Efforts undertaken to harden discrete (missile) and communications systems against EMP are outlined for the example of the Safeguard ABM system, and difficulties are pointed out. Soviet awareness of EMP is considered, and the discovery of vacuum tubes on board the state-of-the-art Foxbat MiG interceptor flown into Japan is noted as a possible indicator of this awareness. It is concluded that the problem of EMP will increase in significance as semiconductor electronics proliferates.

Mineralogical, chemical, and crystallographic properties of supergene jarosite-group minerals from the Xitieshan Pb-Zn sulfide deposit, northern Tibetan Plateau, China

USGS Publications Warehouse

Chen, Lei; Li, Jian-Wei; Rye, Robert O.; Benzel, William H.; Lowers, H.A.; He, Ming-Zhong

2013-01-01

Supergene jarosite-group minerals are widespread in weathering profiles overlying Pb-Zn sulfide ores at Xitieshan, northern Tibetan Plateau, China. They consist predominantly of K-deficient natrojarosite, with lesser amounts of K-rich natrojarosite and plumbojarosite. Electron microprobe (EMP) analyses, scanning electron microcopy (SEM) investigation, and X-ray mapping reveal that the jarosite-group minerals are characterized by spectacular oscillatory zoning composed of alternating growth bands of K-deficient and K-bearing natrojarosite (K2O >1 wt.%). Plumbojarosite, whenever present, occurs as an overgrowth in the outermost bands, and its composition can be best represented by K0.29Na0.19Pb0.31Fe2.66Al0.22(SO4)1.65(PO4)0.31(AsO4)0.04(OH)7.37. The substitution of monovalent for divalent cations at the A site of plumbojarosite is charge balanced by the substitution of five-valent for six-valent anions in XO,4/sub> at the X site. Thermogravimetric analysis (TGA) of representative samples reveal mass losses of 11.46 wt.% at 446.6 °C and 21.42 wt.% at 683.4 °C due to dehydroxylation and desulfidation, respectively. TGA data also indicate that the natrojarosite structure collapses at 446.6 °C, resulting in the formation of NaFe(SO4)2 and minor hematite. The decomposition products of NaFe(SO4) are hematite and Na,2SO4. Powder X-ray diffraction (XRD) analyses show that the jarosite-group minerals have mean unit-cell parameters of a=7.315 ä and c=016.598 ä. XRD and EMP data support the view that substitutions of Na for K in the A site and full Fe occupancy in the B site can considerably decrease the unit-cell parameter c, but only slightly increase a. The results from this study suggest that the observed oscillatory zoning of jarosite-group minerals at Xitieshan resulted mainly from substitutions of K for Na at the A site and P for S at the X site.

Development of a new EMP code at LANL

NASA Astrophysics Data System (ADS)

Colman, J. J.; Roussel-Dupré, R. A.; Symbalisty, E. M.; Triplett, L. A.; Travis, B. J.

2006-05-01

A new code for modeling the generation of an electromagnetic pulse (EMP) by a nuclear explosion in the atmosphere is being developed. The source of the EMP is the Compton current produced by the prompt radiation (γ-rays, X-rays, and neutrons) of the detonation. As a first step in building a multi- dimensional EMP code we have written three kinetic codes, Plume, Swarm, and Rad. Plume models the transport of energetic electrons in air. The Plume code solves the relativistic Fokker-Planck equation over a specified energy range that can include ~ 3 keV to 50 MeV and computes the resulting electron distribution function at each cell in a two dimensional spatial grid. The energetic electrons are allowed to transport, scatter, and experience Coulombic drag. Swarm models the transport of lower energy electrons in air, spanning 0.005 eV to 30 keV. The swarm code performs a full 2-D solution to the Boltzmann equation for electrons in the presence of an applied electric field. Over this energy range the relevant processes to be tracked are elastic scattering, three body attachment, two body attachment, rotational excitation, vibrational excitation, electronic excitation, and ionization. All of these occur due to collisions between the electrons and neutral bodies in air. The Rad code solves the full radiation transfer equation in the energy range of 1 keV to 100 MeV. It includes effects of photo-absorption, Compton scattering, and pair-production. All of these codes employ a spherical coordinate system in momentum space and a cylindrical coordinate system in configuration space. The "z" axis of the momentum and configuration spaces is assumed to be parallel and we are currently also assuming complete spatial symmetry around the "z" axis. Benchmarking for each of these codes will be discussed as well as the way forward towards an integrated modern EMP code.

Electromagnetic pulse (EMP) radiation by laser interaction with a solid H2 ribbon

NASA Astrophysics Data System (ADS)

De Marco, M.; Krása, J.; Cikhardt, J.; Velyhan, A.; Pfeifer, M.; Dudžák, R.; Dostál, J.; Krouský, E.; Limpouch, J.; Pisarczyk, T.; Kalinowska, Z.; Chodukowski, T.; Ullschmied, J.; Giuffrida, L.; Chatain, D.; Perin, J.-P.; Margarone, D.

2017-08-01

The electromagnetic pulses (EMPs) generated during the interaction of a focused 1.315-μm sub-nanosecond laser pulse with a solid hydrogen ribbon were measured. The strength and temporal characteristics of EMPs were found to be dependent on the target density. If a low density target is ionized during the interaction with the laser, and the plasma does not physically touch the target holder, the EMP is weaker in strength and shorter in time duration. It is shown that during the H2 target experiment, the EMP does not strongly affect the response of fast electronic devices. The measurements of the EMP were carried out by Rohde&Schwarz B-Probes, particularly sensitive in the frequency range from 30 MHz and 1 GHz. Numerical simulations of resonant frequencies of the target chamber used in the experiment at the Prague Asterix Laser System kJ-class laser facility elucidate the peaked structure of EMP frequency spectra in the GHz domain.

Nuclear EMP simulation for large-scale urban environments. FDTD for electrically large problems.

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

Smith, William S.; Bull, Jeffrey S.; Wilcox, Trevor

2012-08-13

In case of a terrorist nuclear attack in a metropolitan area, EMP measurement could provide: (1) a prompt confirmation of the nature of the explosion (chemical or nuclear) for emergency response; and (2) and characterization parameters of the device (reaction history, yield) for technical forensics. However, urban environment could affect the fidelity of the prompt EMP measurement (as well as all other types of prompt measurement): (1) Nuclear EMP wavefront would no longer be coherent, due to incoherent production, attenuation, and propagation of gamma and electrons; and (2) EMP propagation from source region outward would undergo complicated transmission, reflection, andmore » diffraction processes. EMP simulation for electrically-large urban environment: (1) Coupled MCNP/FDTD (Finite-difference time domain Maxwell solver) approach; and (2) FDTD tends to be limited to problems that are not 'too' large compared to the wavelengths of interest because of numerical dispersion and anisotropy. We use a higher-order low-dispersion, isotropic FDTD algorithm for EMP propagation.« less

New edge magnetoplasmon interference like photovoltage oscillations and their amplitude enhancement in the presence of an antidot lattice

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

Bisotto, I., E-mail: isabelle.bisotto@lncmi.cnrs.fr; Portal, J.-C.; Institut National des Sciences Appliquées, 31077 Toulouse Cedex 4

2015-11-15

We present new photovoltage oscillation in a pure two dimensional electron gas (2DEG) and in the presence of circular or semicircular antidot lattices. Results were interpreted as EMPs-like photovoltage oscillations. We observed and explained the photovoltage oscillation amplitude enhancement in the presence of an antidot lattice with regard to the pure 2DEG. The microwave frequency excitation range is 139 – 350 GHz. The cyclotron and magnetoplasmon resonances take place in the magnetic field range 0.4 – 0.8 T. This original experimental condition allows edge magnetoplasmons EMPs interference like observation at low magnetic field, typically B < B{sub c} where B{submore » c} is the magnetic field at which the cyclotron resonance takes place. The different oscillation periods observed and their microwave frequency dependence were discussed. For 139 and 158 GHz microwave excitation frequencies, a unique EMPs-like interference period was found in the presence of antidots whereas two periods were extracted for 295 or 350 GHz. An explanation of this effect is given taking account of strong electron interaction with antidot at low magnetic field. Indeed, electrons involved in EMPs like phenomenon interact strongly with antidots when electron cyclotron orbits are larger than or comparable to the antidot diameter.« less

On a method computing transient wave propagation in ionospheric regions

NASA Technical Reports Server (NTRS)

Gray, K. G.; Bowhill, S. A.

1978-01-01

A consequence of an exoatmospheric nuclear burst is an electromagnetic pulse (EMP) radiated from it. In a region far enough away from the burst, where nonlinear effects can be ignored, the EMP can be represented by a large-amplitude narrow-time-width plane-wave pulse. If the ionosphere intervenes the origin and destination of the EMP, frequency dispersion can cause significant changes in the original pulse upon reception. A method of computing these dispersive effects of transient wave propagation is summarized. The method described is different from the standard transform techniques and provides physical insight into the transient wave process. The method, although exact, can be used in approximating the early-time transient response of an ionospheric region by a simple integration with only explicit knowledge of the electron density, electron collision frequency, and electron gyrofrequency required. As an illustration of the method, it is applied to a simple example and contrasted with the corresponding transform solution.

Testing the Origins of Basalt Fragments fro Apollo 16

NASA Technical Reports Server (NTRS)

Donohue, P. H.; Stevens, R. E.; Neal, C. R.; Zeigler, R. A.

2013-01-01

Several 2-4 mm regolith fragments of basalt from the Apollo 16 site were recently described by [1]. These included a high-Ti vitrophyric basalts (60603,10-16) and one very-low-titanium (VLT) crystalline basalt (65703,9-13). As Apollo 16 was the only highlands sample return mission distant from the maria, identification of basaltic samples at the site indicates input from remote sites via impact processes [1]. However, distinguishing between impact melt and pristine basalt can be notoriously difficult and requires significant sample material [2-6]. The crystal stratigraphy method utilizes essentially non-destructive methods to make these distinctions [7,8]. Crystal stratigraphy combines quantitative petrography in the form of crystal size distributions (CSDs) coupled with mineral geochemistry to reveal the petrogenetic history of samples. The classic CSD plot of crystal size versus population density can reveal insights on growth/cooling rates, residence times, and magma history which in turn can be used to evaluate basaltic vs impact melt origin [7-9]. Electron microprobe (EMP) and laser ablation (LA)-ICP-MS analyses of mineral phases complement textural investigations. Trace element variations document subtle changes occurring during the formation of the samples, and are key in the interpretation and preservation of this rare lunar sample collection.

Electromagnetic pulse (EMP), Part I: Effects on field medical equipment.

PubMed

Vandre, R H; Klebers, J; Tesche, F M; Blanchard, J P

1993-04-01

The electromagnetic pulse (EMP) from a high-altitude nuclear detonation has the potential to cover an area as large as the continental United States with damaging levels of EMP radiation. In this study, two of seven items of medical equipment were damaged by an EMP simulator. Computer circuit analysis of 17 different items showed that 11 of the 17 items would be damaged by current surges on the power cords, while two would be damaged by current surges on external leads. This research showed that a field commander can expect approximately 65% of his electronic medical equipment to be damaged by a single nuclear detonation as far as 2,200 km away.

Micro Electron MicroProbe and Sample Analyzer

NASA Technical Reports Server (NTRS)

Manohara, Harish; Bearman, Gregory; Douglas, Susanne; Bronikowski, Michael; Urgiles, Eduardo; Kowalczyk, Robert; Bryson, Charles

2009-01-01

A proposed, low-power, backpack-sized instrument, denoted the micro electron microprobe and sample analyzer (MEMSA), would serve as a means of rapidly performing high-resolution microscopy and energy-dispersive x-ray spectroscopy (EDX) of soil, dust, and rock particles in the field. The MEMSA would be similar to an environmental scanning electron microscope (ESEM) but would be much smaller and designed specifically for field use in studying effects of geological alteration at the micrometer scale. Like an ESEM, the MEMSA could be used to examine uncoated, electrically nonconductive specimens. In addition to the difference in size, other significant differences between the MEMSA and an ESEM lie in the mode of scanning and the nature of the electron source.

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

Vazehrad, S., E-mail: vazehrad@kth.se; Elfsberg, J., E-mail: jessica.elfsberg@scania.com; Diószegi, A., E-mail: attila.dioszegi@jth.hj.se

An investigation on silicon segregation of lamellar, compacted and nodular graphite iron was carried out by applying a selective, immersion color etching and a modified electron microprobe to study the microstructure. The color etched micrographs of the investigated cast irons by revealing the austenite phase have provided data about the chronology and mechanism of microstructure formation. Moreover, electron microprobe has provided two dimensional segregation maps of silicon. A good agreement was found between the segregation profile of silicon in the color etched microstructure and the silicon maps achieved by electron microprobe analysis. However, quantitative silicon investigation was found to bemore » more accurate than color etching results to study the size of the eutectic colonies. - Highlights: • Sensitivity of a color etchant to silicon segregation is quantitatively demonstrated. • Si segregation measurement by EMPA approved the results achieved by color etching. • Color etched micrographs provided data about solidification mechanism in cast irons. • Austenite grain boundaries were identified by measuring the local Si concentration.« less

Electronic medication packaging devices and medication adherence: a systematic review.

PubMed

Checchi, Kyle D; Huybrechts, Krista F; Avorn, Jerry; Kesselheim, Aaron S

2014-09-24

Medication nonadherence, which has been estimated to affect 28% to 31% of US patients with hypertension, hyperlipidemia, and diabetes, may be improved by electronic medication packaging (EMP) devices (adherence-monitoring devices incorporated into the packaging of a prescription medication). To investigate whether EMP devices are associated with improved adherence and to identify and describe common features of EMP devices. Systematic review of peer-reviewed studies testing the effectiveness of EMP systems in the MEDLINE, EMBASE, PsycINFO, CINAHL, International Pharmaceutical Abstracts, and Sociological Abstracts databases from searches conducted to June 13, 2014, with extraction of associations between the interventions and adherence, as well as other key findings. Each study was assessed for bias using the Cochrane Handbook for Systematic Reviews of Interventions; features of EMP devices and interventions were qualitatively assessed. Thirty-seven studies (32 randomized and 5 nonrandomized) including 4326 patients met inclusion criteria (10 patient interface-only "simple" interventions and 29 "complex" interventions integrated into the health care system [2 qualified for both categories]). Overall, the effect estimates for differences in mean adherence ranged from a decrease of 2.9% to an increase of 34.0%, and the those for differences in the proportion of patients defined as adherent ranged from a decrease of 8.0% to an increase of 49.5%. We identified 5 common EMP characteristics: recorded dosing events and stored records of adherence, audiovisual reminders to cue dosing, digital displays, real-time monitoring, and feedback on adherence performance. Many varieties of EMP devices exist. However, data supporting their use are limited, with variability in the quality of studies testing EMP devices. Devices integrated into the care delivery system and designed to record dosing events are most frequently associated with improved adherence, compared with other devices. Higher-quality evidence is needed to determine the effect, if any, of these low-cost interventions on medication nonadherence and to identify their most useful components.

Effect of electromagnetic pulse exposure on brain micro vascular permeability in rats.

PubMed

Ding, Gui-Rong; Li, Kang-Chu; Wang, Xiao-Wu; Zhou, Yong-Chun; Qiu, Lian-Bo; Tan, Juan; Xu, Sheng-Long; Guo, Guo-Zhen

2009-06-01

To observe the effect of electromagnetic pulse (EMP) exposure on cerebral micro vascular permeability in rats. The whole-body of male Sprague-Dawley rats were exposed or sham exposed to 200 pulses or 400 pulses (1 Hz) of EMP at 200 kV/m. At 0.5, 1, 3, 6, and 12 h after EMP exposure, the permeability of cerebral micro vascular was detected by transmission electron microscopy and immunohistochemistry using lanthanum nitrate and endogenous albumin as vascular tracers, respectively. The lanthanum nitrate tracer was limited to the micro vascular lumen with no lanthanum nitrate or albumin tracer extravasation in control rat brain. After EMP exposure, the lanthanum nitrate ions reached the tight junction, basal lamina and pericapillary tissue. Similarly, the albumin immunopositive staining was identified in pericapillary tissue. The changes in brain micro vascular permeability were transient, the leakage of micro vascular vessels appeared at 1 h, and reached its peak at 3 h, and nearly recovered at 12 h, after EMP exposure. In addition, the leakage of micro vascular was more obvious after exposure of EMP at 400 pulses than after exposure of EMP at 200 pulses. Exposure to 200 and 400 pulses (1 Hz) of EMP at 200 kV/m can increase cerebral micro vascular permeability in rats, which is recoverable.

Neuroprotective Effects of Sevoflurane against Electromagnetic Pulse-Induced Brain Injury through Inhibition of Neuronal Oxidative Stress and Apoptosis

PubMed Central

Wang, Jin; Han, Li-Chun; Li, Li-Ya; Wu, Guang-Li; Hou, Yan-Ning; Guo, Guo-Zhen; Wang, Qiang; Sang, Han-Fei; Xu, Li-Xian

2014-01-01

Electromagnetic pulse (EMP) causes central nervous system damage and neurobehavioral disorders, and sevoflurane protects the brain from ischemic injury. We investigated the effects of sevoflurane on EMP-induced brain injury. Rats were exposed to EMP and immediately treated with sevoflurane. The protective effects of sevoflurane were assessed by Nissl staining, Fluoro-Jade C staining and electron microscopy. The neurobehavioral effects were assessed using the open-field test and the Morris water maze. Finally, primary cerebral cortical neurons were exposed to EMP and incubated with different concentration of sevoflurane. The cellular viability, lactate dehydrogenase (LDH) release, superoxide dismutase (SOD) activity and malondialdehyde (MDA) level were assayed. TUNEL staining was performed, and the expression of apoptotic markers was determined. The cerebral cortexes of EMP-exposed rats presented neuronal abnormalities. Sevoflurane alleviated these effects, as well as the learning and memory deficits caused by EMP exposure. In vitro, cell viability was reduced and LDH release was increased after EMP exposure; treatment with sevoflurane ameliorated these effects. Additionally, sevoflurane increased SOD activity, decreased MDA levels and alleviated neuronal apoptosis by regulating the expression of cleaved caspase-3, Bax and Bcl-2. These findings demonstrate that Sevoflurane conferred neuroprotective effects against EMP radiation-induced brain damage by inhibiting neuronal oxidative stress and apoptosis. PMID:24614080

Neuroprotective effects of sevoflurane against electromagnetic pulse-induced brain injury through inhibition of neuronal oxidative stress and apoptosis.

PubMed

Deng, Bin; Xu, Hao; Zhang, Jin; Wang, Jin; Han, Li-Chun; Li, Li-Ya; Wu, Guang-Li; Hou, Yan-Ning; Guo, Guo-Zhen; Wang, Qiang; Sang, Han-Fei; Xu, Li-Xian

2014-01-01

Electromagnetic pulse (EMP) causes central nervous system damage and neurobehavioral disorders, and sevoflurane protects the brain from ischemic injury. We investigated the effects of sevoflurane on EMP-induced brain injury. Rats were exposed to EMP and immediately treated with sevoflurane. The protective effects of sevoflurane were assessed by Nissl staining, Fluoro-Jade C staining and electron microscopy. The neurobehavioral effects were assessed using the open-field test and the Morris water maze. Finally, primary cerebral cortical neurons were exposed to EMP and incubated with different concentration of sevoflurane. The cellular viability, lactate dehydrogenase (LDH) release, superoxide dismutase (SOD) activity and malondialdehyde (MDA) level were assayed. TUNEL staining was performed, and the expression of apoptotic markers was determined. The cerebral cortexes of EMP-exposed rats presented neuronal abnormalities. Sevoflurane alleviated these effects, as well as the learning and memory deficits caused by EMP exposure. In vitro, cell viability was reduced and LDH release was increased after EMP exposure; treatment with sevoflurane ameliorated these effects. Additionally, sevoflurane increased SOD activity, decreased MDA levels and alleviated neuronal apoptosis by regulating the expression of cleaved caspase-3, Bax and Bcl-2. These findings demonstrate that Sevoflurane conferred neuroprotective effects against EMP radiation-induced brain damage by inhibiting neuronal oxidative stress and apoptosis.

Fast probe of local electronic states in nanostructures utilizing a single-lead quantum dot

PubMed Central

Otsuka, Tomohiro; Amaha, Shinichi; Nakajima, Takashi; Delbecq, Matthieu R.; Yoneda, Jun; Takeda, Kenta; Sugawara, Retsu; Allison, Giles; Ludwig, Arne; Wieck, Andreas D.; Tarucha, Seigo

2015-01-01

Transport measurements are powerful tools to probe electronic properties of solid-state materials. To access properties of local electronic states in nanostructures, such as local density of states, electronic distribution and so on, micro-probes utilizing artificial nanostructures have been invented to perform measurements in addition to those with conventional macroscopic electronic reservoirs. Here we demonstrate a new kind of micro-probe: a fast single-lead quantum dot probe, which utilizes a quantum dot coupled only to the target structure through a tunneling barrier and fast charge readout by RF reflectometry. The probe can directly access the local electronic states with wide bandwidth. The probe can also access more electronic states, not just those around the Fermi level, and the operations are robust against bias voltages and temperatures. PMID:26416582

Mitigation of Electromagnetic Pulse (EMP) Effects from Short-Pulse Lasers and Fusion Neutrons

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

Eder, D C; Throop, A; Brown, Jr., C G

2009-03-06

Our research focused on obtaining a fundamental understanding of the source and properties of EMP at the Titan PW(petawatt)-class laser facility. The project was motivated by data loss and damage to components due to EMP, which can limit diagnostic techniques that can be used reliably at short-pulse PW-class laser facilities. Our measurements of the electromagnetic fields, using a variety of probes, provide information on the strength, time duration, and frequency dependence of the EMP. We measure electric field strengths in the 100's of kV/m range, durations up to 100 ns, and very broad frequency response extending out to 5 GHzmore » and possibly beyond. This information is being used to design shielding to mitigate the effects of EMP on components at various laser facilities. We showed the need for well-shielded cables and oscilloscopes to obtain high quality data. Significant work was invested in data analysis techniques to process this data. This work is now being transferred to data analysis procedures for the EMP diagnostics being fielded on the National Ignition Facility (NIF). In addition to electromagnetic field measurements, we measured the spatial and energy distribution of electrons escaping from targets. This information is used as input into the 3D electromagnetic code, EMSolve, which calculates time dependent electromagnetic fields. The simulation results compare reasonably well with data for both the strength and broad frequency bandwidth of the EMP. This modeling work required significant improvements in EMSolve to model the fields in the Titan chamber generated by electrons escaping the target. During dedicated Titan shots, we studied the effects of varying laser energy, target size, and pulse duration on EMP properties. We also studied the effect of surrounding the target with a thick conducting sphere and cube as a potential mitigation approach. System generated EMP (SGEMP) in coaxial cables does not appear to be a significant at Titan. Our results are directly relevant to planned short-pulse ARC (advanced radiographic capability) operation on NIF.« less

Giant microwave-induced B -periodic magnetoresistance oscillations in a two-dimensional electron gas with a bridged-gate tunnel point contact

NASA Astrophysics Data System (ADS)

Levin, A. D.; Mikhailov, S. A.; Gusev, G. M.; Kvon, Z. D.; Rodyakina, E. E.; Latyshev, A. V.

2017-02-01

We have studied the magnetoresistance of a quantum point contact fabricated on a high mobility two-dimensional electron gas (2DEG) exposed to microwave irradiation. The resistance reveals giant B -periodic oscillations with a relative amplitude Δ R /R of up to 700 % resulting from the propagation and interference of the edge magnetoplasmons (EMPs) in the sample. This giant photoconductance is attributed to the considerably large local electron density modulation in the vicinity of the point contact. We have also analyzed the oscillation periods Δ B of the resistance oscillations and, comparing the data with the EMP theory, extracted the EMP interference length L . We have found that the length L substantially exceeds the distance between the contact leads, and rather corresponds to the distance between metallic contact pads measured along the edge of the 2DEG. This resolves existing controversy in the literature and should help to properly design highly sensitive microwave and terahertz spectrometers based on the discussed effect.

Scanning Electron Microscopy | Materials Science | NREL

Science.gov Websites

platform. The electron microprobe JEOL 8900L is the preference when quantitative composition of specimens , electroluminescence, lateral transport measurements, NFCL JEOL JXA-8900L Electron probe microanalysis Quantitative

Age mapping and dating of monazite on the electron microprobe: Deconvoluting multistage tectonic histories

NASA Astrophysics Data System (ADS)

Williams, Michael L.; Jercinovic, Michael J.; Terry, Michael P.

1999-11-01

High-resolution X-ray mapping and dating of monazite on the electron microprobe are powerful geochronological tools for structural, metamorphic, and tectonic analysis. X-ray maps commonly show complex Th, U, and Pb zoning that reflects monazite growth and overgrowth events. Age maps constructed from the X-ray maps simplify the zoning and highlight age domains. Microprobe dating offers a rapid, in situ method for estimating ages of mapped domains. Application of these techniques has placed new constraints on the tectonic history of three areas. In western Canada, age mapping has revealed multiphase monazite, with older cores and younger rims, included in syntectonic garnet. Microprobe ages show that tectonism occurred ca. 1.9 Ga, 700 m.y. later than mylonitization in the adjacent Snowbird tectonic zone. In New Mexico, age mapping and dating show that the dominant fabric and triple-point metamorphism occurred during a 1.4 Ga reactivation, not during the 1.7 Ga Yavapai-Mazatzal orogeny. In Norway, monazite inclusions in garnet constrain high-pressure metamorphism to ca. 405 Ma, and older cores indicate a previously unrecognized component of ca. 1.0 Ga monazite. In all three areas, microprobe dating and age mapping have provided a critical textural context for geochronologic data and a better understanding of the complex age spectra of these multistage orogenic belts.

Microprobe studies of microtomed particles of white druse salts in shergottite EETA 79001

NASA Technical Reports Server (NTRS)

Lindstrom, D. J.

1991-01-01

The white druse material in Antarctic shergottite EETA 79001 has attracted much attention as a possible sample fo Martian aqueous deposits. Instrumental Neutron Activation Analysis (INAA) was used to determine trace element analyses of small particles of this material obtained by handpicking of likely grains from broken surfaces of the meteorite. Electron microprobe work was attempted on grain areas as large as 150x120 microns. Backscattered electron images show considerable variations in brightness, and botryoidal structures were observed. Microprobe analyses showed considerable variability both within single particles and between different particles. Microtomed surfaces of small selected particles were shown to be very useful in obtaining information on the texture and composition of rare lithologies like the white druse of EETA 79001. This material is clearly heterogeneous on all distance scales, so a large number of further analyses will be required to characterize it.

Trace elemental analysis of bituminuos coals using the Heidelberg proton microprobe

USGS Publications Warehouse

Chen, J.R.; Kneis, H.; Martin, B.; Nobiling, R.; Traxel, K.; Chao, E.C.T.; Minkin, J.A.

1981-01-01

Trace elements in coal can occur as components of either the organic constituents (macerals) or the inorganic constituents (minerals). Studies of the concentrations and distribution of the trace elements are vital to understanding the geochemical millieu in which the coal was formed and in evaluating the attempts to recover rare but technologically valuable metals. In addition, information on the trace element concentrations is important in predicting the environmental impact of burning particular coals, as many countries move toward greater utilization of coal reserves for energy production. Traditionally, the optical and the electron microscopes and more recently the electron microprobe have been used in studying the components of coal. The proton-induced X-ray emission (PIXE) microprobe offers a new complementary approach with an order of magnitude or more better minimum detection limit. We present the first measurements with a PIXE microprobe of the trace element concentrations of bituminous coal samples. Elemental analyses of the coal macerals-vitrinite, exinite, and inertinite-are discussed for three coal samples from the Eastern U.S.A., three samples from the Western U.S.A., and one sample from the Peoples Republic of China. ?? 1981.

New Capabilities in the Analysis of Sub-micrometer Regions in Geological Materials with the Field Emission Electron Microprobe

NASA Astrophysics Data System (ADS)

Armstrong, J. T.; McSwiggen, P.; Nielsen, C.

2013-12-01

Quantitative electron microprobe analysis has revolutionized two-dimensional elemental analysis of Earth materials at the micrometer-scale. Newly available commercial field emission (FE-) source instruments represent significant technological advances in quantitative measurement with high spatial resolution at sub-micrometer scale - helping to bridge the gap between conventional microprobe and AEM analyses. Their performance specifications suggest the ability to extend routine quantitative analyses from ~3-5 micrometer diameter areas down to 1-2 micrometer diameter at beam energies of 15 keV; and, with care, down to 200-500 nm diameter at reduced beam energies. . In order to determine whether the level of performance suggested by the specifications is realistic, we spent a week doing analyses at the newly installed JEOL JXA-8530F field emission microprobe at Arizona State University, using a series of samples that are currently being studied in various projects at CIW. These samples included: 1) high-pressure experiment run product containing intergrowths of sub-micrometer grains of metal, sulfide, Fe-Mg-perovskite, and ferropericlase; 2) a thin section of the Ivankinsky basalt, part of the Siberian flood basalt sequence containing complex sub-micrometer intergrowths of magnetite, titanomagnetite, ilmenite, titanite and rutile; 3) a polished section of the Giroux pallasite, being studied for element partitioning, that we used as an analogue to test the capabilities for zonation and diffusion determination; and 4) a polished section of the Semarkona ordinary chondrite containing chondules comprised of highly zoned and rimmed olivines and pyroxenes in a complex mesostasis of sub-micrometer pyroxenes and glass. The results of these analyses that we will present confirmed our optimism regarding the new analytical capabilities of a field emission microprobe. We were able, at reduced voltages, to accurately analyze the major and minor element composition of intergrowth and rimming phases as small as 200 nm without artifact contribution from the surrounding phases. We were able to determine the compositional gradients at kamacite-taenite boundaries in the pallasite specimen with a resolution of ~180 nm, enabling much higher precision and accuracy determination of the meteorite's cooling rate than previously possible with microprobe measurements. We were able to determine the composition and zonation of phases in the experimental run product, none of which were large enough to be analyzable in a conventional electron microprobe.

Physical properties of elongated magnetic particles: magnetization and friction coefficient anisotropies.

PubMed

Vereda, Fernando; de Vicente, Juan; Hidalgo-Alvarez, Roque

2009-06-02

Anisotropy counts: A brief review of the main physical properties of elongated magnetic particles (EMPs) is presented. The most important characteristic of an EMP is the additional contribution of shape anisotropy to the total anisotropy energy of the particle, when compared to spherical magnetic particles. The electron micrograph shows Ni-ferrite microrods fabricated by the authors.We present an overview of the main physical properties of elongated magnetic particles (EMPs), including some of their more relevant properties in suspension. When compared to a spherical magnetic particle, the most important characteristic of an EMP is an additional contribution of shape anisotropy to the total anisotropy energy of the particle. Increasing aspect ratios also lead to an increase in both the critical single-domain size of a magnetic particle and its resistance to thermally activated spontaneous reversal of the magnetization. For single-domain EMPs, magnetization reversal occurs primarily by one of two modes, coherent rotation or curling, the latter being facilitated by larger aspect ratios. When EMPs are used to prepare colloidal suspensions, other physical properties come into play, such as their anisotropic friction coefficient and the consequent enhanced torque they experience in a shear flow, their tendency to align in the direction of an external field, to form less dense sediments and to entangle into more intricate aggregates. From a more practical point of view, EMPs are discussed in connection with two interesting types of magnetic colloids: magnetorheological fluids and suspensions for magnetic hyperthermia. Advances reported in the literature regarding the use of EMPs in these two systems are included. In the final section, we present a summary of the most relevant methods documented in the literature for the fabrication of EMPs, together with a list of the most common ferromagnetic materials that have been synthesized in the form of EMPs.

Synthesis, crystal structures, quantum chemical studies and corrosion inhibition potentials of 4-(((4-ethylphenyl)imino)methyl)phenol and (E)-4-((naphthalen-2-ylimino) methyl) phenol Schiff bases

NASA Astrophysics Data System (ADS)

Elemike, Elias E.; Nwankwo, Henry U.; Onwudiwe, Damian C.; Hosten, Eric C.

2017-11-01

Two Schiff base ligands, 4-(((4-ethylphenyl)imino)methyl)phenol (4EMP) and (E)-4-((naphthalen-2-ylimino) methyl) phenol (4NMP) were synthesized by the reaction of 4-hydroxybenzaldehyde with 4-ethylaniline, 4EMP, or naphthalene-2-amine, 4NMP. The compounds were characterized using NMR (1H and 13C), Fourier transform infra-red (FTIR) and mass spectroscopic techniques. The proton NMR identified the OH peaks at 9.73 and 9.77 ppm for 4EMP and 4NMP respectively, while the 13C NMR showed the imine carbons at 172.57 ppm for 4EMP and at 160.89 ppm for 4NMP. The FTIR spectra showed characteristic peaks at 1605 cm-1 (4EMP) and 1600 cm-1 (4NMP) typical of the azomethine group, and the mass spectra results gave molecular ion peaks of 226.12 and 248.10 respectively. The structures of the compounds were further established by single crystal X-ray analysis. The corrosion inhibition potential of the compounds were studied on mild steel surface in a 1 M hydrochloric acid (HCl) solution, and was analysed using potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS). The results of the electrochemical methods showed that the studied molecules imparted high resistance in allowing flow of electrons across the metal-electrolyte platform and behaved as mixed type inhibitors with 4EMP showing better inhibition properties than 4NMP. Scanning electron microscopy (SEM) showed the formation of film on the mild steel surface. Quantum chemical calculations achieved by density functional theory (DFT) was further applied to explain the adsorption as well as inhibition abilities of the molecules on the mild steel surface. Thermodynamics studies showed that the two compounds obeyed the Langmuir isotherm with 4EMP conforming to chemisorption mechanism while 4NMP involved competitive physisorption and chemisorption mechanism.

Rapid correction of electron microprobe data for multicomponent metallic systems

NASA Technical Reports Server (NTRS)

Gupta, K. P.; Sivakumar, R.

1973-01-01

This paper describes an empirical relation for the correction of electron microprobe data for multicomponent metallic systems. It evaluates the empirical correction parameter, a for each element in a binary alloy system using a modification of Colby's MAGIC III computer program and outlines a simple and quick way of correcting the probe data. This technique has been tested on a number of multicomponent metallic systems and the agreement with the results using theoretical expressions is found to be excellent. Limitations and suitability of this relation are discussed and a model calculation is also presented in the Appendix.

$ANBA; a rapid, combined data acquisition and correction program for the SEMQ electron microprobe

USGS Publications Warehouse

McGee, James J.

1983-01-01

$ANBA is a program developed for rapid data acquisition and correction on an automated SEMQ electron microprobe. The program provides increased analytical speed and reduced disk read/write operations compared with the manufacturer's software, resulting in a doubling of analytical throughput. In addition, the program provides enhanced analytical features such as averaging, rapid and compact data storage, and on-line plotting. The program is described with design philosophy, flow charts, variable names, a complete program listing, and system requirements. A complete operating example and notes to assist in running the program are included.

Experimental determination of growth rate effect on U 6+ and Mg 2+ partitioning between aragonite and fluid at elevated U 6+ concentration

NASA Astrophysics Data System (ADS)

Gabitov, R. I.; Gaetani, G. A.; Watson, E. B.; Cohen, A. L.; Ehrlich, H. L.

2008-08-01

Results are reported from an experimental study in which the partitioning of U and Mg between aragonite and an aqueous solution were determined as a function of crystal growth rate. Crystals, identified as aragonite by X-ray diffractometry and micro-Raman spectroscopy, were grown by diffusion of CO 2 from an ammonium carbonate source into a calcium-bearing solution at temperatures of 22 and 53 °C. Hemispherical bundles (spherulites) of aragonite crystals were produced, the growth rates of which decreased monotonically from the spherulite interiors to the edges and thus provide the opportunity to examine the influence of growth rate on crystal composition. Element concentration ratios were measured using electron microprobe (EMP) and fluid composition was determined by inductively coupled plasma-mass spectrometry (ICP-MS) and atomic absorption (AA). Growth rates were determined directly by addition of a Dy spike to the fluid during the experiment that was subsequently located in an experimentally precipitated spherulite using secondary ion mass spectrometry (SIMS). At 22 °C both U/Ca and Mg/Ca partition coefficients exhibited a strong growth rate dependence when crystal growth rates were low, and became independent of growth rate when crystal growth rates were high. The U/Ca ratios in aragonite increase between 22 and 53 °C; in contrast Mg/Ca ratios show inverse dependence on temperature.

Electromagnetic pulse (EMP), Part II: Field-expedient ways to minimize its effects on field medical treatment facilities.

PubMed

Vandre, R H; Klebers, J; Tesche, F M; Blanchard, J P

1993-05-01

Part I of this paper showed that a field commander can expect approximately 65% of his unprotected electronic medical equipment to be damaged by the electromagnetic pulse (EMP) from a single nuclear detonation as far as 2200 km away. Using computer modeling, field-expedient ways to minimize the effects of EMP were studied. The results were: (1) keep wiring near the ground, (2) keep wiring short, (3) unplug unused equipment, (4) run power cabling and tents in a magnetic north-south direction (avoid running power cabling in the east-west direction), and (5) place sensitive equipment in International Organization for Standardization shelters.

Complementary microanalysis of Zn, Mn and Fe in the chelicera of spiders and scorpions using scanning MeV-ion and electron microprobes

NASA Astrophysics Data System (ADS)

Schofield, Robert; Lefevre, Harlan; Shaffer, Michael

1989-04-01

Energy-loss scanning transmission ion microscopy (ELSTIM or just STIM), PIXE and electron microprobe techniques are used to investigate certain minor element accumulations in a few spiders and scorpions. STIM and PIXE are used to survey the unsectioned specimens, while electron microprobe techniques are used for higher resolution investigations of several sections of the specimens. Concentration values measured using STIM and PIXE are found to be in satisfactory agreement with those measured using electron probe microanalysis. A garden spider Araneus diadematus is found to contain high concentrations of zinc in a thin layer near the surface of its fangs (reaching 23% of dry weight), and manganese in its marginal teeth (about 5% of dry weight). A wolf spider Alopecosa kochi is found to have similar concentrations of zinc in a layer near the surface of it's fang, and concentrations of manganese reaching 1.5% in a layer beneath the zinc containing layer. A scorpion Centruroides sp. is found to contain high concentrations of iron (reaching 8%) and zinc (reaching 24%) in the tips of teeth on the cheliceral fingers, and manganese (about 5%) in the stinger. The hypothesis that these elements simply harden the cuticle does not appear to explain their segregation patterns.

Role of Off-Line-of-Sight Propagation in Geomagnetic EMP Formation

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

Kruger, Hans W.

The author’s synchrotron radiation based 3D geomagnetic EMP code MACSYNC has been used to explore the impact on pulse rise time and air conductivity of EMP propagation paths to the observer that are located off the direct line-of-sight (LOS) between gamma source and observer. This geometry is always present because, for an isotropic source, most the gammas are emitted at an angle with respect to the LOS. Computations for a 1 kt near-surface burst observed from space yield two principal findings: 1. The rise time is generated by the combined actions of a) electron spreading along the LOS due tomore » the Compton electron emission angular distribution folded with electron multiple scattering effects, and b) radiation arrival time spreading due to length differences for different off-LOS propagation paths. The pulse rise time does not depend on the rise time of the conductivity. The conductivity rise time determines the pulse amplitude. 2. One-dimensional legacy EMP codes are inherently incapable of producing the correct pulse shape because they cannot treat the dependence of the conductivity on two dimensions, i.e. the radius from the source and the angle of the propagation path with the LOS. This divergence from one-dimensionality begins at a small fraction of a nanosecond for a sea-level burst. This effect will also be present in high-altitude bursts, however, determination of its onset time and magnitude requires high-altitude computations which have not yet been done.« less

Comparison of AC electronic monitoring and field data for estimating tolerance to Empoasca kraemeri (Homoptera: Cicadellidae) in common bean genotypes.

PubMed

Serrano, M S; Backus, E A; Cardona, C

2000-12-01

Two methods for estimating the tolerance of common bean genotypes to Empoasca kraemeri Ross & Moore were compared, using a yield trial carried out at Centro Internacional de Agricultura Tropical (CIAT), Cali, Colombia, versus stylet penetration tactics measured by AC electronic feeding monitors. A stylet penetration index was devised based on principal component scores of three penetration tactics identified (pulsing laceration, cell rupturing, and lancing sap ingestion), combined with knowledge of the hopperburn symptoms caused by each tactic. Tolerant genotypes, as classified by the CIAT yield index, showed significantly more unprotected yield and lower hopperburn scores than the susceptible control. They also induced performance of less pulsing laceration (the tactic considered most damaging to the plant), and more of the other two, mitigating tactics, especially cell rupturing. When index values were calculated for each genotype, stylet penetration index values matched those of the yield index for three out of five genotypes: two EMP-coded tolerant lines ('EMP 385' and 'EMP 392') and the susceptible control 'BAT 41'. Thus, for these three genotypes, all subsequent hoppereburn symptoms are predictable by the type of feeding behavior performed on them. 'Porrillo Sintético' and 'EMP 84', considered borderline genotypes by the yield index, were overestimated and underestimated respectively, by the stylet penetration index. We postulate that, for these two genotypes, plant physiological responses to feeding (either compensatory or heightened sensitivity, respectively) synergize with type of feeding performed to generate the overall hopperburn condition. This multivariate analysis of electronic monitoring data was successfully used to devise an index of resistance. The implications of using the stylet penetration index and the advantages of using electronic monitoring in a bean-breeding program are discussed.

Electron microprobe evaluation of terrestrial basalts for whole-rock K-Ar dating

USGS Publications Warehouse

Mankinen, E.A.; Brent, Dalrymple G.

1972-01-01

Four basalt samples for whole-rock K-Ar dating were analyzed with an electron microprobe to locate potassium concentrations. Highest concentrations of potassium were found in those mineral phases which were the last to crystallize. The two reliable samples had potassium concentrated in fine-grained interstitial feldspar and along grain boundaries of earlier formed plagioclase crystals. The two unreliable samples had potassium concentrated in the glassy matrix, demonstrating the ineffectiveness of basaltic glass as a retainer of radiogenic argon. In selecting basalt samples for whole-rock K-Ar dating, particular emphasis should be placed on determining the nature and condition of the fine-grained interstitial phases. ?? 1972.

Electron Microprobe Analyses of Lithic Fragments and Their Minerals from Luna 20 Fines

NASA Technical Reports Server (NTRS)

Conrad, G. H.; Hlava, P. F.; Green, J. A.; Moore, R. B.; Moreland, G.; Dowty, E.; Prinz, M.; Keil, K.; Nehru, C. E.; Bunch, T. E.

1973-01-01

The bulk analyses (determined with the broad beam electron microprobe technique) of lithic fragments are given in weight percentages and are arranged according to the rock classification. Within each rock group the analyses are arranged in order of increasing FeO content. Thin section and lithic fragment numbers are given at the top of each column of analysis and correspond to the numbers recorded on photo mosaics on file in the Institute of Meteoritics. CIPW molecular norms are given for each analysis. Electron microprobe mineral analyses (given in oxide weight percentages), structural formulae and molecular end member values are presented for plagioclase, olivine, pyroxene and K-feldspar. The minerals are selected mostly from lithic fragments that were also analyzed for bulk composition. Within each mineral group the analyses are presented according to the section number and lithic fragment number. Within each lithic fragment the mineral analyses are arranged as follows: Plagioclase in order of increasing CaO; olivine and pyroexene in order of increasing FeO; and K-feldspar in order of increasing K2O. The mineral grains are identified at the top of each column of analysis by grain number and lithic fragment number.

Towards Synthesis and Usage of Actinide-Bearing REE Phosphate age Standards: A Progress Report

NASA Astrophysics Data System (ADS)

Pyle, J. M.; Cherniak, D. J.

2006-05-01

Electron microprobe (EMP) dates result from a concentration-time unit conversion, so use of a concentration- based (rather than isotope-ratio based) fictive age standard is warranted. This observation has motivated our mineral synthesis program, aimed at producing actinide-doped REE phosphate EMP dating standards that meet the following criteria: 1) known concentrations of U, Th, and Pb; 2) homogeneous intragrain distribution of all components; 3) of suitable size, either as a single-crystal or polycrystalline sintered ceramic. Single-crystal synthesis of actinide-doped LaPO4 by flux-growth methods results in disproportionation of lanthanide and flux, alkali, and actinide components into phosphate and oxide phases, respectively, and flux- growth methods were abandoned. Actinide-doped La phosphate is successfully prepared by high-T annealing and hydrothermal processing of microcrystalline phosphate; both homogeneity and charge-balance of (Ca, Th, Pb)-bearing LaPO4 increase with increasing solvent acidity during cold-seal hydrothermal synthesis. A combination of pressing and high-T (1400° C) sintering transforms fine-grained (0.1-10 μm) run- products to ceramic pellets with 90-95% theoretical density. Our most recent runs focused on a target composition of La80(CaTh)17(CaU)2(PbTh)1PO4 processed with 6% 2M HCl at 820° C, 0.75 kbar for 1 week. The run products are 0.1-2 μm crystals identified by XRD as La-actinide phosphate solid solution. 2 μm grains (N=16) give a composition (mean±2 sd) of La79.77(1.26)(CaTh)17.87(1.00)(CaU)1.53(0.42)(PbTh)0.82(0.09)PO4. Th (8.07-9.13 wt. %) is homogeneous at the level of analytical precision, and the Pb concentration range (3500-4350 ppm) is restricted relative to untreated precipitate. Uranium concentration values are more variable (6500-10000 ppm). This run yields a fictive age of 702±4 Ma (mean±2 se), compared to the fictive age of 794 Ma for the target composition.

Assessment and Mitigation of Radiation, EMP, Debris & Shrapnel Impacts at Megajoule-Class Laser Facilities

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

Eder, D C; Anderson, R W; Bailey, D S

2009-10-05

The generation of neutron/gamma radiation, electromagnetic pulses (EMP), debris and shrapnel at mega-Joule class laser facilities (NIF and LMJ) impacts experiments conducted at these facilities. The complex 3D numerical codes used to assess these impacts range from an established code that required minor modifications (MCNP - calculates neutron and gamma radiation levels in complex geometries), through a code that required significant modifications to treat new phenomena (EMSolve - calculates EMP from electrons escaping from laser targets), to a new code, ALE-AMR, that is being developed through a joint collaboration between LLNL, CEA, and UC (UCSD, UCLA, and LBL) for debrismore » and shrapnel modelling.« less

Space System Survivability

NASA Astrophysics Data System (ADS)

Kuller, W. G.; Hanifen, D. W.

1982-07-01

Exoatmospheric detonations of nuclear weapons produce a broad spectrum of effects which can prevent operational space missions from being successfully accomplished. The spacecraft may be exposed to the prompt radiation from the detonations which can cause upset or burnout of critical mission components through Transient Radiation Effects on Electronics (TREE) or System Generated Electromagnetic Pulse (SGEMP). Continual exposure to the trapped radiation environment may cause component failure due to total dose or Electron Caused EMP (ECEMP). Satellite links to ground and airborne terminals are subject to serious degradation due to signal absorption and scintillation. The ground data stations and lines of communications are subject to failure from the broad range effects of high-altitude EMP.

Microanalysis of iron oxidation state in iron oxides using X Ray Absorption Near Edge Structure (XANES)

NASA Technical Reports Server (NTRS)

Sutton, S. R.; Delaney, J.; Bajt, S.; Rivers, M. L.; Smith, J. V.

1993-01-01

An exploratory application of x ray absorption near edge structure (XANES) analysis using the synchrotron x ray microprobe was undertaken to obtain Fe XANES spectra on individual sub-millimeter grains in conventional polished sections. The experiments concentrated on determinations of Fe valence in a suite of iron oxide minerals for which independent estimates of the iron speciation could be made by electron microprobe analysis and x ray diffraction.

Zirconium, hafnium, and rare earth element partition coefficients for ilmenite and other minerals in high-Ti lunar mare basalts - An experimental study

NASA Technical Reports Server (NTRS)

Mckay, G.; Wagstaff, J.; Yang, S.-R.

1986-01-01

Partition coefficients were determined for Gd, Lu, Hf and Zr among ilmenite, armalcolite, and synthetic high-Ti mare basaltic melts at temperatures from 1122 deg to 1150 deg, and at oxygen fugacities of IW x 10 exp 0.5, by in situ analysis with an electron microprobe, using samples doped to present concentration levels. Coefficients for Zr were also measured for samples containing 600-1600 ppm Zr using this microprobe. In addition, coefficients were determined for Hf and Zr between chromian ulvospinel and melt, for Hf between pigeonite and melt, and for Lu between olivine and melt by microprobe analysis of samples doped to present levels. Values measured using the microprobe were in agreement with the values measured by analyzing mineral separates from the same run products by isotope dilution. Coefficient values for ilmenite are less than 0.01 for the LREE, are around 0.1 for the HREE, and are several times greater than this for Zr and Hf.

Upper D region chemical kinetic modeling of LORE relaxation times

NASA Astrophysics Data System (ADS)

Gordillo-Vázquez, F. J.; Luque, A.; Haldoupis, C.

2016-04-01

The recovery times of upper D region electron density elevations, caused by lightning-induced electromagnetic pulses (EMP), are modeled. The work was motivated from the need to understand a recently identified narrowband VLF perturbation named LOREs, an acronym for LOng Recovery Early VLF events. LOREs associate with long-living electron density perturbations in the upper D region ionosphere; they are generated by strong EMP radiated from large peak current intensities of ±CG (cloud to ground) lightning discharges, known also to be capable of producing elves. Relaxation model scenarios are considered first for a weak enhancement in electron density and then for a much stronger one caused by an intense lightning EMP acting as an impulsive ionization source. The full nonequilibrium kinetic modeling of the perturbed mesosphere in the 76 to 92 km range during LORE-occurring conditions predicts that the electron density relaxation time is controlled by electron attachment at lower altitudes, whereas above 79 km attachment is balanced totally by associative electron detachment so that electron loss at these higher altitudes is controlled mainly by electron recombination with hydrated positive clusters H+(H2O)n and secondarily by dissociative recombination with NO+ ions, a process which gradually dominates at altitudes >88 km. The calculated recovery times agree fairly well with LORE observations. In addition, a simplified (quasi-analytic) model build for the key charged species and chemical reactions is applied, which arrives at similar results with those of the full kinetic model. Finally, the modeled recovery estimates for lower altitudes, that is <79 km, are in good agreement with the observed short recovery times of typical early VLF events, which are known to be associated with sprites.

Use of scanning electron microscopy and microanalysis to determine chloride content of concrete and raw materials.

DOT National Transportation Integrated Search

2013-02-01

Standard sample sets of cement and mortar formulations with known levels of Cl as well as concrete samples subject to Cl diffusion were all prepared for and analyzed with scanning electron microscopy (SEM) and electron microprobe (EPMA). Using x-ray ...

[Effect of electromagnetic pulse irradiation on structure and function of Leydig cells in mice].

PubMed

Wang, Shui-Ming; Wang, De-Wen; Peng, Rui-Yun; Gao, Ya-Bing; Yang, Yi; Hu, Wen-Hua; Chen, Hao-Yu; Zhang, You-Ren; Gao, Yan

2003-08-01

To explore the effect of electromagnetic pulse (EMP) irradiation on structure and function of Leydig cells in mice. One hundred and fourteen male Kunming mice were randomly divided into irradiated and control group, the former radiated generally by 8 x 10(3) V/m, 2 x 10(4) V/m and 6 x 10(4) V/m EMP respectively five times within two minutes. Pathological changes of Leydig cells were observed by light and electron microscope. Serum testosterone (T), luteinizing hormone (LH) and estradiol (E2) were measured dynamically by radioimmunoassay at 6 h, 1 d, 3 d, 7 d, 14 d and 28 d after irradiation. Main pathological changes were edema and vacuolation, swelling of cytoplasmic mitochondria, reduce of lipid droplets, pale staining of most of lipid droplets, and partial or complete cavitation of lipid droplets in Leydig cells within 28 days after EMP radiation. Compared with normal controls, serum T decreased in all in different degrees within 28 days, and dropped significantly at 6 h-14 d, 6 h-7 d and 1 d-28 d after 8 x 10(3) V/m, 2 x 10(4) V/m and 6 x 10(4) V/m EMP irradiation(P < 0.05 or P < 0.01). EMP irradiation caused no significant changes in serum LH and E2. Leydig cells are among those that are the most susceptible to EMP irradiation. EMP irradiation may cause significant injury in structure and function of Leydig cells in mice, whose earlier and continuous effect is bound to affect sexual function and sperm production.

Evaluation of Surface Roughness of Ceramic and Resin Composite Material Used for Conservative Indirect Restorations, after Repolishing by Intraoral Means.

PubMed

Vrochari, Areti D; Petropoulou, Aikaterini; Chronopoulos, Vasilios; Polydorou, Olga; Massey, Ward; Hellwig, Elmar

2017-06-01

To evaluate and compare the mean surface roughness (Ra) of one ceramic and one resin composite material used for indirect restorations, after grinding and repolishing by intraoral means. The materials used were the lithium disilicate glass ceramic IPS e.max Press (EMP) and the indirect resin composite restoration system Gradia (GR). Twelve specimen disks were prepared from each material according to the manufacturer of each material. Five initial measurements of the Ra (Ra 1 ) were made on each specimen as a referral basis, and the specimens were ground with a fine (red) diamond bur. The specimens were repolished using (a) Komet Dialite Polishing Kit for EMP and (b) Enhance Finishing and Polishing System and Prisma Gloss Polishing Paste for GR. Five final Ra (Ra 2 ) measurements were performed on each specimen. All measurements were made using a laser profilometer. Scanning electron microscopy (SEM) was also used to visualize the initial surface morphology and the morphological changes on the specimens' surface after repolishing. A highly significant difference was found between Ra 1EMP and Ra 2EMP (p < 0.001), between Ra 1GR and Ra 2GR (p < 0.001), as well as between Ra 2EMP and Ra 2GR (p < 0.001), when compared in pairs. A highly significant difference (p < 0.001) was also found between ΔRa EMP and ΔRa GR , with ΔRa GR being higher than ΔRa EMP . The Ra GR values were higher than the Ra EMP values at all times. SEM revealed that both EMP and GR repolished surfaces presented with irregularities; however, in GR specimens major voids and craters were present. EMP was found to perform better when polished by intraoral means compared with GR. Both materials exhibited Ra 2 above the critical threshold for increased plaque accumulation and periodontal inflammation. If enamel-to-enamel roughness found in occlusal contact areas is considered as baseline, both materials were clinically acceptable after repolishing. © 2015 by the American College of Prosthodontists.

Effects of surface chemistry on hot corrosion life

NASA Technical Reports Server (NTRS)

Fryxell, R. E.; Gupta, B. K.

1984-01-01

Hot corrosion life prediction methodology based on a combination of laboratory test data and field service turbine components, which show evidence of hot corrosion, were examined. Components were evaluated by optical metallography, scanning electron microscopy (SEM), and electron micropulse (EMP) examination.

Electro-optic analysis of the influence of target geometry on electromagnetic pulses generated by petawatt laser-matter interactions

NASA Astrophysics Data System (ADS)

Robinson, Timothy; Giltrap, Samuel; Eardley, Samuel; Consoli, Fabrizio; De Angelis, Riccardo; Ingenito, Francesco; Stuart, Nicholas; Verona, Claudio; Smith, Roland A.

2018-01-01

We present an analysis of strong laser-driven electromagnetic pulses using novel electro-optic diagnostic techniques. A range of targets were considered, including thin plastic foils (20-550 nm) and mass-limited, optically-levitated micro-targets. Results from foils indicate a dependence of EMP on target thickness, with larger peak electric fields observed with thinner targets. Spectral analysis suggests high repeatability between shots, with identified spectral features consistently detected with <1 MHz standard deviations of the peak position. This deviation is reduced for shots taken on the same day, suggesting that local conditions, such as movement of metal objects within the target chamber, are more likely to lead to minor spectral modifications, highlighting the role of the local environment in determining the details of EMP production. Levitated targets are electrically isolated from their environment, hence these targets should be unable to draw a neutralization current from the earth following ejection of hot electrons from the plasma, in contrast to predictions for pin-mounted foils in the Poyé EMP generation model. With levitated targets, no EMP was measurable above the noise threshold of any diagnostic, despite observation of protons accelerated to >30 MeV energies, suggesting the discharge current contribution to EMP is dominant.

Increased nitric oxide synthase activity is essential for electromagnetic-pulse-induced blood-retinal barrier breakdown in vivo.

PubMed

Lu, Lianjun; Xu, Hui; Wang, Xiaowu; Guo, Guozhen

2009-04-06

To examine whether electromagnetic pulses (EMPs) affected the permeability of the blood-retinal barrier (BRB), gene expression of occludin and activity of nitric oxide synthase (NOS). Sprague-Dawley (SD) rats were used and randomized into EMP and control groups. Retinas were removed immediately, and 2 h or 24 h after EMP radiation. BRB permeability was analyzed by transmission electron microscopy and Evans Blue staining. Retinal NOS activity and concentrations of nitrite and nitrate were measured. Occludin mRNA and protein levels were detected by RT-PCR and Western blotting. Exposure of SD rats to EMP resulted in increased BRB permeability, with the greatest decrease in occludin at 24 h. Moreover, this permeability defect was also correlated with significant increases in the formation of NO and induction of NOS activity in SD rats. Furthermore, we found that treatment with NOS inhibitor N-nitro-L-arginine methyl ester (L-NAME) blocked BRB breakdown and prevented the increase in NO formation and induction of NOS activity, as well as the decrease in occluding expression. Taken together, these results support the view that NOS-dependent NO production is an important factor that contributes to EMP-induced BRB dysfunction, and suggests that NOS induction may play an important role in BRB breakdown.

Electron microprobe analysis and histochemical examination of the calcium distribution in human bone trabeculae: a methodological study using biopsy specimens from post-traumatic osteopenia

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

Obrant, K.J.; Odselius, R.

1984-01-01

Energy dispersive X-ray microanalysis (EDX) (or electron microprobe analysis) of the relative intensity for calcium in different bone trabeculae from the tibia epiphysis, and in different parts of one and the same trabecula, was performed on 3 patients who had earlier had a fracture of the ipsilateral tibia-diaphysis. The variation in intensity was compared with the histochemical patterns obtained with both the Goldner and the von Kossa staining techniques for detecting calcium in tissues. Previously reported calcium distribution features, found to be typical for posttraumatic osteopenia, such as striated mineralization patterns in individual trabeculae and large differences in mineralization levelmore » between different trabeculae, could be verified both by means of the two histochemical procedures and from the electron microprobe analysis. A pronounced difference was observed, however, between the two histochemical staining techniques as regards their sensitivity to detect calcium. To judge from the values obtained from the EDX measurements, the sensitivity of the Goldner technique should be more than ten times higher than that of von Kossa. The EDX measurements gave more detailed information than either of the two histochemical techniques: great variations in the intensity of the calcium peak were found in trabeculae stained as unmineralized as well as mineralized.« less

Effect of electromagnetic pulse exposure on permeability of blood-testicle barrier in mice.

PubMed

Wang, Xiao-Wu; Ding, Gui-Rong; Shi, Chang-Hong; Zhao, Tao; Zhang, Jie; Zeng, Li-Hua; Guo, Guo-Zhen

2008-06-01

To study the effect of electromagnetic pulse (EMP) exposure on the permeability of blood-testicle barrier (BTB) in mice. Adult male BALB/c mice were exposed to EMP at 200 kV/m for 200 pulses with 2 seconds interval. The mice were injected with 2% Evans Blue solution through caudal vein at different time points after exposure, and the permeability of BTB was monitored using a fluorescence microscope. The testis sample for the transmission electron microscopy was prepared at 2 h after EMP exposure. The permeability of BTB in mice was observed by using Evans Blue tracer and lanthanum nitrate tracer. After exposure, cloudy Evans Blue was found in the testicle convoluted seminiferous tubule of mice. Lanthanum nitrate was observed not only between testicle spermatogonia near seminiferous tubule wall and sertoli cells, but also between sertoli cells and primary spermatocyte or secondary spermatocyte. In contrast, lanthanum nitrate in control group was only found in the testicle sertoli cells between seminiferous tubule and near seminiferous tubule wall. EMP exposure could increase the permeability of BTB in the mice.

Multi probes measurements at the PALS Facility Research Centre during high intense laser pulse interactions with various target materials

NASA Astrophysics Data System (ADS)

De Marco, Massimo; Krása, Josef; Cikhardt, Jakub; Consoli, Fabrizio; De Angelis, Riccardo; Pfeifer, Miroslav; Krůs, Miroslav; Dostál, Jan; Margarone, Daniele; Picciotto, Antonino; Velyhan, Andriy; Klír, Daniel; Dudžák, Roman; Limpouch, Jiří; Korn, Georg

2018-01-01

During the interaction of high intense laser pulse with solid target, a large amount of hot electrons is produced and a giant Electromagnetic Pulse (EMP) is generated due to the current flowing into the system target-target holder, as well as due to the escaping charged particles in vacuum. EMP production for different target materials is investigated inside and outside the target chamber, using monopole antenna, super wide-band microstrip antenna and Moebius antenna. The EMP consists in a fast transient magnetic field lasting hundreds of nanosecond with frequencies ranging from MHz to tens of GHz. Measurements of magnetic field and return target current in the range of kA were carried out by an inductive target probe (Cikhardt J. et al. Rev. Sci. Instrum. 85 (2014) 103507).

Effects of electromagnetic pulse (EMP) on cardiac pacemakers. Final report, Nov 88-Oct 89

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

Ellis, V.J.

1991-11-01

The U.S. Army Harry Diamond Laboratories' (HDL's) Woodbridge Research Facility (WRF) has conducted an investigation into the effects of electromagnetic pulse (EMP) on medical electronics. This report specifically documents the findings on the effects of WRF's Army EMP Simulator Operations (AESOP) on cardiac pacemakers (CPMs). Empirical data are furnished and compared to the results of two independent analytical studies. The studies support the conclusion that damage to CPMs that might be located near the WRF boundaries is not likely. Furthermore, any upset in a CPM's operation is considered unlikely and inconsequential to the health of the CPM wearer. Cardiac pacemakersmore » (CPMs) have experienced significant technological advancements over the last decade, evolving from simple and bulky pulse generators to the small and sophisticated computerized units implanted today. With the implementation of sensitive digital electronics in modern pacemaker designs, concerns have been expressed for the possibility of an increased sensitivity of CPMs to electromagnetic interference (EMI). To some extent these concerns have abated to the increased awareness of the EMI problem by the manufacturers, as evident in better peacemaker designs and the decline in reported malfunctions due to EMI.« less

Numerical simulation of narrow bipolar electromagnetic pulses generated by thunderstorm discharges

NASA Astrophysics Data System (ADS)

Bochkov, E. I.; Babich, L. P.; Kutsyk, I. M.

2013-07-01

Using the concept of avalanche relativistic runaway electrons (REs), we perform numerical simulations of compact intracloud discharge (CID) as a generator of powerful natural electromagnetic pulses (EMPs) in the HF-VHF range, called narrow bipolar pulses (NBPs). For several values of the field overvoltage and altitude at which the discharge develops, the numbers of seed electrons initiating the avalanche are evaluated, with which the calculated EMP characteristics are consistent with the measured NBP parameters. We note shortcomings in the hypothesis assuming participation of cosmic ray air showers in avalanche initiation. The discharge capable of generating NBPs produces REs in numbers close to those in the source of terrestrial γ-ray flashes (TGFs), which can be an argument in favor of a unified NBP and TGF source.

Central Antarctic provenance of Permian sandstones in Dronning Maud Land and the Karoo Basin: Integration of U Pb and TDM ages and host-rock affinity from detrital zircons

NASA Astrophysics Data System (ADS)

Veevers, J. J.; Saeed, A.

2007-12-01

In conjugate SE Africa and Antarctica, Early Permian sandstones of the Swartrant Formation of the Ellisras Basin, Vryheid Formation of the Karoo Basin, and Amelang Plateau Formation of Dronning Maud Land (DML) were deposited after Gondwanan glaciation on a westward paleoslope. We analysed detrital zircons for U-Pb ages by a laser ablation microprobe-inductively coupled plasma mass spectrometer (LAM-ICPMS) and attached age significance only to clusters of three or more overlapping analyses. We analysed Hf-isotope compositions by a multi-collector spectrometer (LAM-MC-ICPMS) and trace elements by electron microprobe (EMP) and ICPMS. These analyses indicate the rock type and source (whether crustal or juvenile mantle) of the host magma, and a "crustal" model age ( TDMC). The integrated analysis gives a more distinctive, and more easily interpreted, picture of crustal evolution in the provenance area than age data alone. Zircons from the Ellisras Basin are aged 2700-2540 Ma with minor populations about 2815 Ma and 2040 Ma, which correspond with the ages of the upslope parts of the proximal Kaapvaal Craton and Limpopo Belt. Mafic rock is the dominant host rock, and it reflects the Archean granite-greenstone terrane of the Kaapvaal Craton. The three Karoo Basin samples and the two DML samples have zircons with these common properties: (1) 1160-880 Ma, host magma mafic granitoid (< 65% SiO 2) derived from juvenile depleted mantle sources ( ɛHf positive) at 1.65 Ga and 1.35 Ga, with TDMC of 2.0-0.9 Ga; (2) 760 to 480 Ma, host magma granitoid and low-heavy rare earth element rock (?alkaline rock-carbonatite), derived from mixed crustal and juvenile depleted mantle sources ( ɛHf positive and negative) at 1.50 Ga and 1.35 Ga, with TDMC of 2.0-0.9 Ga. Together with similar detrital zircons in Triassic sandstone of SE Australia, these properties reflect those in upslope central Antarctica, indicating a provenance of ˜ 1000 Ma (Grenville) cratons embedded in 700-500 Ma (Pan-Gondwanaland) fold belts. Detrital zircons in Cambrian sediments of the Ellsworth-Whitmore Mountains block and Cambrian metasediments of the Welch Mountains with comparable properties suggest that the central Antarctic provenance operated also in the ˜ 500 Ma Cambrian.

The evolution of high-alumina basalts of the Klyuchevskoy volcano, Kamchatka, Russia, based on microprobe analyses of mineral inclusions

NASA Astrophysics Data System (ADS)

Ozerov, Alexei Y.

2000-01-01

The origin of calc-alkaline high-alumina basalts (HAB) of the Klyuchevskoy volcano, Kamchatka, was examined using electron microprobe analyses of phenocrysts and mineral phases included in the phenocrysts. Continuous trends on major-element variation diagrams suggest the HAB were derived from high-magnesia basalt (HMB) by fractional crystallization. Phenocrysts in the HAB are strongly zoned: olivine (Mg# 91-64), clinopyroxene (Wo 45-38En 40-51Fs 5-20) and chrome—spinel/magnetite inclusions in them (Cr 2O 3 45-0 wt.%, TiO 2 0.5-11%). Microprobe analyses of minerals included in the phenocrysts provide additional constraints on the mineral crystallization trends in the HAB. Fe/Mg partitioning data, when applied to the phenocrysts cores, show they crystallized from a HMB. The similarity of phenocryst core compositions in HAB with those in HMB strongly suggests a genetic relationship between the two magma types.

Internal Stratigraphy of the Palisades Sill Olivine Zone: An Olivine Slurry Emplaced in a Hot Sill

NASA Astrophysics Data System (ADS)

Haddad, J. R.; Naslund, H. R.

2017-12-01

The Palisades Sill is a 300 m thick Jurassic-Triassic sill-like sheet formed from a quartz-normative tholeiitic magma. Three geochemical reversals within the sill are the result of magma chamber recharges. This study focuses on the reversal at 10 m height, widely considered to be the result of the emplacement of an olivine-rich slurry (Husch 1990, Gorring 1995). Major and trace elements were determined for 35 samples from the olivine layer and adjacent sill spanning 10 m of stratigraphic height. Samples were collected from outcrops near the Ross Dock Picnic Area in Fort Lee, NJ. Mineral compositions were determined for 21 thin sections using an electron microprobe (EMP). Bulk rock chemistry shows that the base of the olivine layer is between 2.5 and 3.25 m above the base of sampling. This is indicated by a marked reversal in Mg#, which jumped from 64.2 to 68.6; Al2O3, Co, Ni, Sc, Cs, Dy, and La also show clear reversals at the same interval. This is further collaborated by the formation of a ledge in the outcrop. Bulk chemistry and olivine composition show no systematic changes within the olivine layer. EMP analyses of augites reveals that below the 2.5 m height, crystals are typically strongly zoned, average rim Mg#= 67, core Mg#= 82. Above the 2.5 m layer, core Mg# are similar, but average rim Mg#=75. The plagioclase/augite ratio remains relatively constant through the olivine layer, but the ratio of olivine to plagioclase+augite is quite variable, suggesting that the olivine-slurry was emplaced as an inhomogeneous mixture of olivine + magma. Similar tholeiitic sills on Victoria Island, Canada, contain olivine-rich basal layers in which the olivine to plagioclase+augite ratio systematically increases, and the olivine composition becomes systematically more Fe-rich, from the base to the top of the layer. Comparisons between these otherwise similar basal olivine-rich layers, suggests that sills like the Palisades, which represents the injection of an olivine-rich slurry, can be distinguished from sills like the Victoria Island sills, which represent the initial emplacement of an olivine-phyric magma, followed by post-emplacement crystal settling.

Crystal structure refinement and Mössbauer spectroscopy of an ordered, triclinic clinochlore

USGS Publications Warehouse

Smyth, Joseph R.; Dyar, M. Darby; May, Howard M.; Bricker, Owen P.; Acker, James G.

1997-01-01

The crystal structure of a natural, ordered IIb-4 triclinic clinochlore has been refined in space group C1¯ from 4282 unique X-ray intensity measurements of which 3833 are greater than 3 times the statistical counting error (3σ). Unit cell parameters are a = 5.3262(6) Å; b = 9.226(1) Å; c = 14.334(3) Å; α = 90.56(2)°; β = 97.47(2)°; and γ = 89.979(9)°, which represents the greatest deviation from monoclinic symmetry yet recorded for a triclinic chlorite. The final weighted R is 0.059 for reflections with I > 3σ and 0.064 for all reflections. The chemical formula is (Mg0.966Fe0.034)M1(Mg0.962Fe0.038)M22(Si2.96Al1.04)O10 (OH)2(Mg0.996Fe0.004)M32(Al0.841FeIII0.102Cr0.004Ti0.004)M4(OH)6, which is consistent with electron microprobe (EMP), wet chemical analyses, Mössbauer spectroscopy and X-ray structure refinement. The high degree of ordering of the divalent versus trivalent octahedral cations in the interlayer is noteworthy, with FeIII and Al in M4 and virtually no Fe in M3. In the 2:1 layer, M1 and M2 each contain similar amounts of Fe. The 2 tetrahedral sites have nearly identical mean oxygen distances and volumes, and thus show no evidence of long-range cation ordering.

Reproducibility of Clathromorphum compactum coralline algal Mg/Ca ratios and comparison to high-resolution sea surface temperature data

NASA Astrophysics Data System (ADS)

Hetzinger, S.; Halfar, J.; Kronz, A.; Simon, K.; Adey, W. H.; Steneck, R. S.

2018-01-01

The potential of crustose coralline algae as high-resolution archives of past ocean variability in mid- to high-latitudes has only recently been recognized. Few comparisons of coralline algal proxies, such as temperature-dependent algal magnesium to calcium (Mg/Ca) ratios, with in situ-measured surface ocean data exist, even rarer are well replicated records from individual sites. We present Mg/Ca records from nine coralline algal specimens (Clathromorphum compactum) from a single site in the Gulf of Maine, North Atlantic. Sections from algal mounds were analyzed using Laser Ablation-Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) yielding individual Mg/Ca records of up to 30 years in length. We first test intra- and intersample signal replication and show that algal Mg/Ca ratios are reproducible along several transects within individual sample specimens and between different samples from the same study site. In addition, LA-ICP-MS-derived Mg/Ca ratios are compared to electron microprobe (EMP) analyzed data on the longest-lived specimens and were found to be statistically commensurable. Second, we evaluate whether relationships between algal-based SST reconstructions and in situ temperature data can be improved by averaging Mg/Ca records from multiple algal specimens (intersample averages). We found that intersample averages yield stronger relationships to sea surface temperature (SST) data than Mg/Ca records derived from individual samples alone. Thus, Mg/Ca-based paleotemperature reconstructions from coralline algae can benefit from using multiple samples per site, and can expand temperature proxy precision from seasonal to monthly.

Electron multiplier-ion detector system

DOEpatents

Dietz, L.A.

1975-08-01

This patent relates to an improved ion detector for use in mass spectrometers for pulse counting signal ions which may have a positive or a negative charge. The invention combines a novel electron multiplier with a scintillator type of ion detector. It is a high vacuum, high voltage device intended for use in ion microprobe mass spectrometers. (auth)

Quantitative simultaneous multi-element microprobe analysis using combined wavelength and energy dispersive systems

NASA Technical Reports Server (NTRS)

Walter, L. S.; Doan, A. S., Jr.; Wood, F. M., Jr.; Bredekamp, J. H.

1972-01-01

A combined WDS-EDS system obviates the severe X-ray peak overlap problems encountered with Na, Mg, Al and Si common to pure EDS systems. By application of easily measured empirical correction factors for pulse pile-up and peak overlaps which are normally observed in the analysis of silicate minerals, the accuracy of analysis is comparable with that expected for WDS electron microprobe analyses. The continuum backgrounds are subtracted for the spectra by a spline fitting technique based on integrated intensities between the peaks. The preprocessed data are then reduced to chemical analyses by existing data reduction programs.

The grape cluster, metal particle 63344,1. [in lunar coarse fines

NASA Technical Reports Server (NTRS)

Goldstein, J. I.; Axon, H. J.; Agrell, S. O.

1975-01-01

The grape cluster metal particle 63344,1 found in lunar coarse fines is examined using the scanning electron microscope (SEM), electron microprobe, and an optical microscope. This metal particle is approximately 0.5 cm in its largest dimension and consists of hundreds of metallic globules welded together to form a structure somewhat like a bunch of grapes. Electron microprobe analysis for Fe, Ni, Co, P, and S in the metal was carried out using wavelength dispersive detectors. No primary solidification structure is observed in the globules, and the particle is slow cooled from the solidification temperature (nearly 1300 C) taking days to probably months to reach 600 C. Two mechanisms for the formation of globules are proposed. One mechanism involves the primary impact of an iron meteorite which produces a metallic liquid and vapor phase. The second mechanism involves the formation of a liquid pool of metal after impact of an iron meteorite projectile followed by a secondary impact in the liquid metal pool.

Fine-scale traverses in cumulate rocks, Stillwater Complex: A lunar analogue study

NASA Technical Reports Server (NTRS)

Elthon, Donald

1988-01-01

The objective was to document finite-scale compositional variations in cumulate rocks from the Stillwater Complex in Montana and to interpret these data in the context of planetary magma fractionation processes such as those operative during the formation of the Earth's Moon. This research problem involved collecting samples in the Stillwater Complex and analyzing them by electron microprobe, X-ray fluorescence (XRF), and instrumental neutron activation analysis (INAA). The electron microprobe is used to determine the compositions of cumulus and intercumulus phases in the rocks, the XRF is used to determine the bulk-rock major element and trace element (Y, Sr, Rb, Zr, Ni, and Cr) abundances, and the INAA lab. is used to determine the trace element (Sc, Co, Cr, Ni, Ta, Hf, U, Th, and the REE) abundances of mineral separates and bulk rocks.

The cause of outliers in electromagnetic pulse (EMP) locations

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

Fenimore, Edward E.

2014-10-02

We present methods to calculate the location of EMP pulses when observed by 5 or more satellites. Simulations show that, even with a good initial guess and fitting a location to all of the data, there are sometime outlier results whose locations are much worse than most cases. By comparing simulations using different ionospheric transfer functions (ITFs), it appears that the outliers are caused by not including the additional path length due to refraction rather than being caused by not including higher order terms in the Appleton-Hartree equation. We suggest ways that the outliers can be corrected. These correction methodsmore » require one to use an electron density profile along the line of sight from the event to the satellite rather than using the total electron content (TEC) to characterize the ionosphere.« less

Calibration Issues and Operating System Requirements for Electron-Probe Microanalysis

NASA Technical Reports Server (NTRS)

Carpenter, P.

2006-01-01

Instrument purchase requirements and dialogue with manufacturers have established hardware parameters for alignment, stability, and reproducibility, which have helped improve the precision and accuracy of electron microprobe analysis (EPMA). The development of correction algorithms and the accurate solution to quantitative analysis problems requires the minimization of systematic errors and relies on internally consistent data sets. Improved hardware and computer systems have resulted in better automation of vacuum systems, stage and wavelength-dispersive spectrometer (WDS) mechanisms, and x-ray detector systems which have improved instrument stability and precision. Improved software now allows extended automated runs involving diverse setups and better integrates digital imaging and quantitative analysis. However, instrumental performance is not regularly maintained, as WDS are aligned and calibrated during installation but few laboratories appear to check and maintain this calibration. In particular, detector deadtime (DT) data is typically assumed rather than measured, due primarily to the difficulty and inconvenience of the measurement process. This is a source of fundamental systematic error in many microprobe laboratories and is unknown to the analyst, as the magnitude of DT correction is not listed in output by microprobe operating systems. The analyst must remain vigilant to deviations in instrumental alignment and calibration, and microprobe system software must conveniently verify the necessary parameters. Microanalysis of mission critical materials requires an ongoing demonstration of instrumental calibration. Possible approaches to improvements in instrument calibration, quality control, and accuracy will be discussed. Development of a set of core requirements based on discussions with users, researchers, and manufacturers can yield documents that improve and unify the methods by which instruments can be calibrated. These results can be used to continue improvements of EPMA.

Experimental Shock Decomposition of Siderite and the Origin of Magnetite in Martian Meteorite ALH84001

NASA Technical Reports Server (NTRS)

Bell, Mary Sue

2007-01-01

Shock recovery experiments to determine whether magnetite could be produced by the decomposition of iron-carbonate were initiated. Naturally occurring siderite was first characterized by electron microprobe (EMP), transmission electron microscopy (TEM), Mossbauer spectroscopy, and magnetic susceptibility measurements to be sure that the starting material did not contain detectable magnetite. Samples were shocked in tungsten-alloy holders (W=90%, Ni=6%, Cu=4%) to further insure that any iron phases in the shock products were contributed by the siderite rather than the sample holder. Each sample was shocked to a specific pressure between 30 to 49 GPa. Previously reported results of TEM analyses on 49 GPa experiments indicated the presence of nano-phase spinel-structured iron oxide. Transformation of siderite to magnetite as characterized by TEM was found in the 49 GPa shock experiment. Compositions of most magnetites are greater than 50% Fe sup(+2) in the octahedral site of the inverse spinel structure. Magnetites produced in shock experiments display the same range of single-domain, superparamagnetic sizes (approx. 50 100 nm), compositions (100% magnetite to 80% magnetite-20% magnesioferrite), and morphologies (equant, elongated, euhedral to subhedral) as magnetites synthesized by Golden et al. (2001) or magnetites grown naturally by MV1 magnetotactic bacteria, and as the magnetites in Martian meteorite ALH84001. Fritz et al. (2005) previously concluded that ALH84001 experienced approx. 32 GPa pressure and a resultant thermal pulse of approx. 100 - 110 C. However, ALH84001 contains evidence of local temperature excursions high enough to 1 melt feldspar, pyroxene, and a silica-rich phase. This 49 GPa experiment demonstrates that magnetite can be produced by the shock decomposition of siderite as a result of local heating to greater than 470 C. Therefore, magnetite in the rims of carbonates in Martian meteorite ALH84001 could be a product of shock devolatilization of siderite as well.

Petrology and Geochemistry of the NWA 3368 Eucrite

NASA Astrophysics Data System (ADS)

Gardner, K. G.; Lauretta, D. S.; Hill, D. H.; Goreva, J. S.; Domanik, K. J.; Franchi, I. A.; Drake, M. J.

2006-03-01

We report the petrology and geochemistry of NWA 3368, a new non-cumulate, monomict eucrite breccia with a variety of clast sizes and a pink-tinted matrix. Analytical techniques include electron microprobe, INAA, and ICP-MS.

Inter- and intra-group compositional variations in Apollo 15 pyroclastic green glass - An electron- and ion-microprobe study

NASA Technical Reports Server (NTRS)

Galbreath, K. C.; Shearer, C. K.; Papike, J. J.; Shimizu, N.

1990-01-01

Results are presented on major- and trace-element abundance analyses of Apollo 15 pyroclastic green glasses from groups A, B, C, D, and E, carried out using electron- and ion-microprobe techniques. The diagrams depicting Sr, Zr, Ba, and Nd vs Co variations indicate the presence of a high-Co trend in groups A and D and a low-Co trend in groups B and C. Group-E glasses were found to be significantly enriched in Sr, relative to the other four glass groups. Chemical data of this study were integrated with previous data to evaluate various magmatic processes that have been proposed in the past to explain chemical variations in the lunar green glass. Results of calculations using a source mixing model suggest that the Apollo 15 green glasses represent multiple eruptive events from three chemically distinct but compositionally variable source regions.

MICROCHARACTERIZATION OF ARSENIC- AND SELENIUM-BEARING PYRITE IN UPPER FREEPORT COAL, INDIANA COUNTY, PENNSYLVANIA.

USGS Publications Warehouse

Minkin, J.A.; Finkelman, R.B.; Thompson, C.L.; Chao, E.C.T.; Ruppert, L.F.; Blank, H.; Cecil, C.B.

1984-01-01

Optical and scanning electron microscope as well as electron and proton microprobe techniques have been used in a detailed investigation of the modes of occurrence of arsenic and selenium in pyrite in Upper Freeport coal from the Homer City area, Indiana County, Pennsylvania. Polished blocks were prepared from columnar samples of the coal bed to represent particular zones continuously from top to bottom. Initial selection of zones to be studied was based on chemical analysis of bench-channel samples. Microprobe data indicate that the highest concentrations of arsenic (as great as 1. 5 wt. %) are apparently in solid solution in pyrite within a limited stratigraphic interval of the coal bed. Smaller amounts of arsenic and selenium (concentrations up to approximately 0. 1 and 0. 2 wt. % respectively) were detected at isolated points within pyrite grains in various strata of the coal bed.

Electron microprobe analyses of Ca, S, Mg and P distribution in incisors of Spacelab-3 rats

NASA Technical Reports Server (NTRS)

Rosenberg, G. D.; Simmons, D. J.

1985-01-01

The distribution of Ca, S, Mg and P was mapped within the incisors of Spacelab-3 rats using an electron microprobe. The data indicate that Flight rats maintained in orbit for 7 days have significantly higher Ca/Mg ratios in dentin due to both higher Ca and lower Mg content than in dentin of ground-based Controls. There is no statistical difference in distribution of either P or S within Fligth animals and Controls, but there is clear indication that, for P at least, the reason is the greater variability of the Control data. These results are consistent with those obtained on a previous NASA/COSMOS flight of 18.5 days duration, although they are not pronounced. The results further suggest that continuously growing rat incisors provide useful records of the effects of weightlessness on Ca metabolism.

Silver and mercury in single gold grains from the Witwatersrand and Barberton, South Africa

NASA Astrophysics Data System (ADS)

von Gehlen, K.

1983-10-01

The contents of silver and mercury in 323 spots on gold grains from seven localities of the Witwatersrand palaeo-placer and Archaean vein deposits from Barberton were measured using an electron microprobe. The objective was to obtain information on the extent of gold alteration during fluvial transport and post-depositional geological processes. The results, however, show that Ag and Hg are distributed homogeneously in the gold grains studied. No indications were found that the gold was transported in solution nor that leaching took place in an oxidizing fluvial environment. This strongly suggests that the Ag and Hg contents in Witwatersrand gold grains represent geochemical ‘fingerprints’ inherited from their eroded primary sources. Combined analysis for Ag and Hg in Witwatersrand gold grains by electron microprobe can therefore be a valuable tool in establishing the types of primary sources for the gold.

A High Resolution Microprobe Study of EETA79001 Lithology C

NASA Technical Reports Server (NTRS)

Schrader, Christian M.; Cohen, B. A.; Donovan, J. J.; Vicenzi, E. P.

2010-01-01

Antarctic meteorite EETA79001 has received substantial attention for possibly containing a component of Martian soil in its impact glass (Lithology C) [1]. The composition of Martian soil can illuminate near-surface processes such as impact gardening [2] and hydrothermal and volcanic activity [3,4]. Impact melts in meteorites represent our most direct samples of Martian regolith. We present the initial findings from a high-resolution electron microprobe study of Lithology C from Martian meteorite EETA79001. As this study develops we aim to extract details of a potential soil composition and to examine Martian surface processes using elemental ratios and correlations.

Ion microprobe magnesium isotope analysis of plagioclase and hibonite from ordinary chondrites

NASA Technical Reports Server (NTRS)

Hinton, R. W.; Bischoff, A.

1984-01-01

Ion and electron microprobes were used to examine Mg-26 excesses from Al-26 decay in four Al-rich objects from the type 3 ordinary hibonite clast in the Dhajala chondrite. The initial Al-26/Al-27 ratio was actually significantly lower than Al-rich inclusions in carbonaceous chondrites. Also, no Mg-26 excesses were found in three plagioclase-bearing chondrules that were also examined. The Mg-26 excesses in the hibonite chondrites indicated a common origin for chondrites with the excesses. The implied Al-26 content in a proposed parent body could not, however, be confirmed as a widespread heat source in the early solar system.

The Mars Microprobe Mission: Advanced Micro-Avionics for Exploration Surface

NASA Astrophysics Data System (ADS)

Blue, Randel

2000-01-01

The Mars Microprobe Mission is the second spacecraft developed as part of the New Millennium Program deep space missions. The objective of the Microprobe Project is to demonstrate the applicability of key technologies for future planetary missions by developing two probes for deployment on Mars. The probes are designed with a single stage entry, descent, and landing system and impact the Martian surface at speeds of approximately 200 meters per second. The microprobes are composed of two main sections, a forebody section that penetrates to a depth below the Martian surface of 0.5 to 2 meters, and an aftbody section that remains on the surface. Each probe system consists of a number of advanced technology components developed specifically for this mission. These include a non-erosive aeroshell for entry into. the atmosphere, a set of low temperature batteries to supply probe power, an advanced microcontroller to execute the mission sequence, collect the science data, and react to possible system fault conditions, a telecommunications subsystem implemented on a set of custom integrated circuits, and instruments designed to provide science measurements from above and below the Martian surface. All of the electronic components have been designed and fabricated to withstand the severe impact shock environment and to operate correctly at predicted temperatures below -100 C.

RN12 and RN30 Epidote anlayses

DOE Data Explorer

Andrew Fowler

2015-01-01

Results for laser ablation measurement of reare earth elments and electron microprobe analysis of major elments in hydrothermal epidote. Laser ablation measurements were completed using an Agilent 7700 quadrupole ICP-MS coupled with 193nm Photon Instruments Excimer laser.

230Th-U dating of surficial deposits using the ion microprobe (SHRIMP-RG): A microstratigraphic perspective

USGS Publications Warehouse

Maher, K.; Wooden, J.L.; Paces, J.B.; Miller, D.M.

2007-01-01

We used the sensitive high-resolution ion microprobe reverse-geometry (SHRIMP-RG) to date pedogenic opal using the 230Th-U system. Due to the high-spatial resolution of an ion microprobe (typically 30 ??m), regions of pure opal within a sample can be targeted and detrital material can be avoided. In addition, because the technique is non-destructive, the sample can be preserved for other types of analyses including electron microprobe or other stable isotope or trace element ion microprobe measurements. The technique is limited to material with U concentrations greater than ???50 ppm. However, the high spatial resolution, small sample requirements, and the ability to avoid detrital material make this technique a suitable technique for dating many Pleistocene deposits formed in semi-arid environments. To determine the versatility of the method, samples from several different deposits were analyzed, including silica-rich pebble coatings from pedogenic carbonate horizons, a siliceous sinter deposit, and opaline silica deposited as a spring mound. U concentrations for 30-??m-diameter spots ranged from 50 to 1000 ppm in these types of materials. The 230Th/232Th activity ratios also ranged from ???100 to 106, eliminating the need for detrital Th corrections that reduce the precision of traditional U-Th ages for many milligram- and larger-sized samples. In pedogenic material, layers of high-U opal (ca. 500 ppm) are commonly juxtaposed next to layers of calcite with much lower U concentrations (1-2 ppm). If these types of samples are not analyzed using a technique with the appropriate spatial resolution, the ages may be strongly biased towards the age of the opal. Comparison with standard TIMS (Thermal Ionization Mass Spectrometry) measurements from separate microdrilled samples suggests that although the analytical precision of the ion microprobe (SHRIMP-RG) measurements is less than TIMS, the high spatial resolution results in better accuracy in the age determination for finely layered or complex deposits. The ion microprobe approach also may be useful for pre-screening samples to determine the age and degree of post-depositional alteration, analyzing finely layered samples or samples with complex growth histories, and obtaining simultaneous measurements of trace elements.

Hot Corrosion Degradation of Metals and Alloys - A Unified Theory

DTIC Science & Technology

1979-06-01

microscope, electron beam microprobe and X-ray diffraction. REULTS AND DMCtESION Hot Corrosion Degradation Sectuence In attempting to develop a unified...Figure 40a. Such ghost images, which can be called corrosion front ghosts , appear as sequential dark and light zones in electron backscatter images... Electronic and Solid State Sciences AUG Ill 1979I Bolling AFB, D.C. 20332 ID PRATT &WHITNEY ARCRAFT GROUP P.O . Box 2861 /Government Products Division wi

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

Chambers, W.F.; Doyle, J.H.

QUANT is a special schedule for electron microprobes which are automated with Tracor Northern electronics. QUANT is called from the SANDIA TASK-78 control program and provides simultaneous data acquisition and data reduction capabilities using either a first principles atomic number, absorption, fluorescence (ZAF) technique or a matrix correction (Bence--Albee) technique. During operation, QUANT controls the execution of three auxiliary programs - BA78, ZAF78, and SETUP.

Sinonasal extramedullary plasmacytoma: a population-based incidence and survival analysis.

PubMed

Patel, Tapan D; Vázquez, Alejandro; Choudhary, Moaz M; Kam, David; Baredes, Soly; Eloy, Jean Anderson

2015-09-01

Sinonasal extramedullary plasmacytoma (SN-EMP) is a rare plasma cell neoplasm. Published literature on this tumor largely consists of case reports and case-series with small sample sizes. This study analyzed population-based data on SN-EMP patients to understand demographic and clinical features as well as incidence and survival trends. The Surveillance, Epidemiology, and End Results (SEER) database was queried for SN-EMP and other head and neck EMP (HN-EMP) cases from 1973 to 2011. Cases were analyzed to determine patient demographics, initial treatment modality, and survival outcomes. Of 778 patients identified with EMP in the head and neck region, 367 patients had SN-EMP and 411 had other HN-EMP. There was a strong male predilection found, with a male-to-female ratio of 3.65:1 in the SN-EMP group and 1.87:1 in the other HN-EMP group. The majority of the patients presented with localized disease in both SN-EMP (84.4%) and other HN-EMP (81.0%) groups. The most common treatment modality reported in this database was surgery with adjuvant radiotherapy in both SN-EMP (46.3%) and other HN-EMP (38.9%) groups, followed by radiotherapy alone (SN-EMP: 40.7%; other HN-EMP: 34.2%). Five-year and 10-year disease-specific survival rates were comparable between SN-EMP (88.2% and 83.3%, respectively) and other HN-EMP (90.0% and 87.4%, respectively) (p = 0.6016 and p = 0.4015, respectively). This study analyzed the largest cohort of SN-EMP patients to date. There was no statistically significant survival advantage found for any 1 particular treatment modality over other treatment modalities in both SN-EMP and other HN-EMP. © 2015 ARS-AAOA, LLC.

Endothelial microparticles (EMP) bind and activate monocytes: elevated EMP-monocyte conjugates in multiple sclerosis.

PubMed

Jy, Wenche; Minagar, Alireza; Jimenez, Joaquin J; Sheremata, William A; Mauro, Lucia M; Horstman, Lawrence L; Bidot, Carlos; Ahn, Yeon S

2004-09-01

Elevated plasma endothelial microparticles (EMP) have been documented in MS during exacerbation. However, the role of EMP in pathogenesis of MS remains unclear. We investigated the formation of EMP-monocyte conjugates (EMP-MoC) and their potential role in transendothelial migration of inflammatory cells in MS. EMP-MoC were assayed in 30 MS patients in exacerbation, 20 in remission and in 35 controls. EMP-leukocyte conjugation was investigated flowcytometrically by employing alpha-CD54 or alpha-CD62E for EMP, and alpha-CD45 for leukocytes. EMP-MoC were characterized by identifying adhesion molecules involved and their effect on monocyte function. In vivo (clinical): EMP-MoC were markedly elevated in exacerbation vs. remission and controls, correlating with presence of GD+ MRI lesions. Free CD54+ EMP were not elevated but free CD62E+ EMP were. In vitro: EMP bound preferentially to monocytes, less to neutrophils, but little to lymphocytes. Bound EMP activated monocytes: CD11b expression increased 50% and migration through cerebral endothelial cell layer increased 2.6-fold. Blockade of CD54 reduced binding by 80%. Most CD54+ EMP bound to monocytes, leaving little free EMP, while CD62+ EMP were found both free and bound. These results demonstrated that phenotypic subsets of EMP interacted differently with monocytes. Based on our observations, EMP may enhance inflammation and increase transendothelial migration of monocytes in MS by binding to and activating monocytes through CD54. EMP-MoC were markedly increased in MS patients in exacerbation compared to remission and may serve as a sensitive marker of MS disease activity.

Plasma properties and heating at the anode of a 1 kW arcjet using electrostatic probes

NASA Astrophysics Data System (ADS)

Tiliakos, Nicholas

A 1 kW hydrazine arcjet thruster has been modified for internal probing of the near-anode boundary layer with an array of fourteen electrostatic micro-probes. The main objectives of this experimental investigation were to: (1) obtain axial and azimuthal distributions of floating potential phisbf, anode sheath potential phisbs, probe current density at zero volts jsba, electron number density nsbes, electron temperature Tsbes, and anode heating due to electrons qsbe for arc currents Isbarc, between 7.8 and 10.6 A, propellant flow rates m = 40-60 mg/s, and specific energies, 18.8 MJ/kg ≤ P/m ≤ 27.4 MJ/kg; (2) probe the anode boundary layer using flush-mounted and cylindrical micro-probes; (3) verify azimuthal current symmetry; (4) understand what affects anode heating, a critical thruster lifetime issue; and (5) provide experimental data for validation of the Megli-Krier-Burton (MKB) model. All of the above objectives were met through the design, fabrication and implementation of fourteen electrostatic micro-probes, of sizes ranging from 0.170 mm to 0.43 mm in diameter. A technique for cleaning and implementing these probes was developed. Two configurations were used: flush-mounted planar probes and cylindrical probes extended 0.10-0.30 mm into the plasma flow. The main results of this investigation are: (1) electrostatic micro-probes can successfully be used in the harsh environment of an arcjet; (2) under all conditions tested the plasma is highly non-equilibrium in the near-anode region; (3) azimuthal current symmetry exists for most operating conditions; (4) the propellant flow rate affects the location of maximum anode sheath potential, current density, and anode heating more than the arc current; (5) the weighted anode sheath potential is always positive and varies from 8-17 V depending on thruster operating conditions; (6) the fraction of anode heating varies from 18-24% of the total input power over the range of specific energies tested; and (7) based on an energy loss factor of delta = 1200, reasonable correlation between the experimental data and the MKB model was found.

Newly recognized hosts for uranium in the Hanford Site vadose zone

USGS Publications Warehouse

Stubbs, J.E.; Veblen, L.A.; Elbert, D.C.; Zachara, J.M.; Davis, J.A.; Veblen, D.R.

2009-01-01

Uranium contaminated sediments from the U.S. Department of Energy's Hanford Site have been investigated using electron microscopy. Six classes of solid hosts for uranium were identified. Preliminary sediment characterization was carried out using optical petrography, and electron microprobe analysis (EMPA) was used to locate materials that host uranium. All of the hosts are fine-grained and intergrown with other materials at spatial scales smaller than the analytical volume of the electron microprobe. A focused ion beam (FIB) was used to prepare electron-transparent specimens of each host for the transmission electron microscope (TEM). The hosts were identified as: (1) metatorbernite [Cu(UO2)2(PO4)2??8H2O]; (2) coatings on sediment clasts comprised mainly of phyllosilicates; (3) an amorphous zirconium (oxyhydr)oxide found in clast coatings; (4) amorphous and poorly crystalline materials that line voids within basalt lithic fragments; (5) amorphous palagonite surrounding fragments of basaltic glass; and (6) Fe- and Mn-oxides. These findings demonstrate the effectiveness of combining EMPA, FIB, and TEM to identify solid-phase contaminant hosts. Furthermore, they highlight the complexity of U geochemistry in the Hanford vadose zone, and illustrate the importance of microscopic transport in controlling the fate of contaminant metals in the environment. ?? 2008 Elsevier Ltd.

Single ion hit detection set-up for the Zagreb ion microprobe

NASA Astrophysics Data System (ADS)

Smith, R. W.; Karlušić, M.; Jakšić, M.

2012-04-01

Irradiation of materials by heavy ions accelerated in MV tandem accelerators may lead to the production of latent ion tracks in many insulators and semiconductors. If irradiation is performed in a high resolution microprobe facility, ion tracks can be ordered by submicrometer positioning precision. However, full control of the ion track positioning can only be achieved by a reliable ion hit detection system that should provide a trigger signal irrespectively of the type and thickness of the material being irradiated. The most useful process that can be utilised for this purpose is emission of secondary electrons from the sample surface that follows the ion impact. The status report of the set-up presented here is based on the use of a channel electron multiplier (CEM) detector mounted on an interchangable sample holder that is inserted into the chamber in a close geometry along with the sample to be irradiated. The set-up has been tested at the Zagreb ion microprobe for different ions and energies, as well as different geometrical arrangements. For energies of heavy ions below 1 MeV/amu, results show that efficient (100%) control of ion impact can be achieved only for ions heavier than silicon. The successful use of the set-up is demonstrated by production of ordered single ion tracks in a polycarbonate film and by monitoring fluence during ion microbeam patterning of Foturan glass.

PIXSIC: A Pixellated Beta-Microprobe for Kinetic Measurements of Radiotracers on Awake and Freely Moving Small Animals

NASA Astrophysics Data System (ADS)

Godart, J.; Weiss, P.; Chantepie, B.; Clemens, J. C.; Delpierre, P.; Dinkespiler, B.; Janvier, B.; Jevaud, M.; Karkar, S.; Lefebvre, F.; Mastrippolito, R.; Menouni, M.; Pain, F.; Pangaud, P.; Pinot, L.; Morel, C.; Laniece, P.

2010-06-01

We present a design study of PIXSIC, a new β+ radiosensitive microprobe implantable in rodent brain dedicated to in vivo and autonomous measurements of local time activity curves of beta radiotracers in a small (a few mm3) volume of brain tissue. This project follows the initial β microprobe previously developed at IMNC, which has been validated in several neurobiological experiments. This first prototype has been extensively used on anesthetized animals, but presents some critical limits for utilization on awake and freely moving animals. Consequently, we propose to develop a wireless setup that can be worn by an animal without constraints upon its movements. To that aim, we have chosen a Silicon-based detector, highly β sensitive, which allows for the development of a compact pixellated probe (typically 600 × 200 × 1000 μm3), read out with miniaturized wireless electronics. Using Monte-Carlo simulations, we show that high resistive Silicon pixels are appropriate for this purpose, assuming that the pixel dimensions are adapted to our specific signals. More precisely, a tradeoff has to be found between the sensitivity to β+ particles and to the 511 keV j background resulting from annihilations of β+ with electrons. We demonstrate that pixels with maximized surface and minimized thickness can lead to an optimization of their β+ sensitivity with a relative transparency to the annihilation background.

Role of the Emp Pilus Subunits of Enterococcus faecium in Biofilm Formation, Adherence to Host Extracellular Matrix Components, and Experimental Infection

PubMed Central

Montealegre, Maria Camila; Singh, Kavindra V.; Somarajan, Sudha R.; Yadav, Puja; Chang, Chungyu; Spencer, Robert; Sillanpää, Jouko; Ton-That, Hung

2016-01-01

Enterococcus faecium is an important cause of hospital-associated infections, including urinary tract infections (UTIs), bacteremia, and infective endocarditis. Pili have been shown to play a role in the pathogenesis of Gram-positive bacteria, including E. faecium. We previously demonstrated that a nonpiliated ΔempABC::cat derivative of E. faecium TX82 was attenuated in biofilm formation and in a UTI model. Here, we studied the contributions of the individual pilus subunits EmpA, EmpB, and EmpC to pilus architecture, biofilm formation, adherence to extracellular matrix (ECM) proteins, and infection. We identified EmpA as the tip of the pili and found that deletion of empA reduced biofilm formation to the same level as deletion of the empABC operon, a phenotype that was restored by reconstituting in situ the empA gene. Deletion of empB also caused a reduction in biofilm, while EmpC was found to be dispensable. Significant reductions in adherence to fibrinogen and collagen type I were observed with deletion of empA and empB, while deletion of empC had no adherence defect. Furthermore, we showed that each deletion mutant was significantly attenuated in comparison to the isogenic parental strain, TX82, in a mixed-inoculum UTI model (P < 0.001 to 0.048), that reconstitution of empA restored virulence in the UTI model, and that deletion of empA also resulted in attenuation in an infective endocarditis model (P = 0.0088). Our results indicate that EmpA and EmpB, but not EmpC, contribute to biofilm and adherence to ECM proteins; however, all the Emp pilins are important for E. faecium to cause infection in the urinary tract. PMID:26930703

New Martian Meteorite Is One of the Most Oxidized Found to Date

NASA Technical Reports Server (NTRS)

Hui, Hejiu; Peslier, Anne; Lapen, Thomas J.; Shafer, John T.; Brandon, Alan D.; Irving, Anthony J.

2014-01-01

As of 2013, about 60 meteorites from the planet Mars have been found and are being studied. Each time a new Martian meteorite is found, a wealth of new information comes forward about the red planet. The most abundant type of Martian meteorite is a shergottite; its lithologies are broadly similar to those of Earth basalts and gabbros; i.e., crustal igneous rocks. The entire suite of shergottites is characterized by a range of trace element, isotopic ratio, and oxygen fugacity values that mainly reflect compositional variations of the Martian mantle from which these magmas came. A newly found shergottite, NWA 5298, was the focus of a study performed by scientists within the Astromaterials Research and Exploration Science (ARES) Directorate at the Johnson Space Center (JSC) in 2012. This sample was found in Morocco in 2008. Major element analyses were performed in the electron microprobe (EMP) laboratory of ARES at JSC, while the trace elements were measured at the University of Houston by laser inductively coupled plasma mass spectrometry (ICPMS). A detailed analysis of this stone revealed that this meteorite is a crystallized magma that comes from the enriched end of the shergottite spectrum; i.e., trace element enriched and oxidized. Its oxidation comes in part from its mantle source and from oxidation during the magma ascent. It represents a pristine magma that did not mix with any other magma or see crystal accumulation or crustal contamination on its way up to the Martian surface. NWA 5298 is therefore a direct, albeit evolved, melt from the Martian mantle and, for its lithology (basaltic shergottite), it represents the oxidized end of the shergottite suite. It is thus a unique sample that has provided an end-member composition for Martian magmas.

Phosphate reactivity in long-term poultry litter-amended southern Delaware sandy soils

USGS Publications Warehouse

Arai, Y.; Livi, K.J.T.; Sparks, D.L.

2005-01-01

Eutrophication caused by dissolved P from poultry litter (PL)-amended agricultural soils has been a serious environmental concern in the Delaware-Maryland-Virginia Peninsula (Delmarva), USA. To evaluate state and federal nutrient management strategies for reducing the environmental impact of soluble P from long-term PL-amended Delaware (DE) soils, we investigated (i) inorganic P speciation; (ii) P adsorption capacity; and (iii) the extent of P desorption. Although the electron microprobe (EMP) analyses showed a strong correlation between P and Al/Fe, crystalline Al/Fe-P precipitates were not detected by x-ray diffraction (XRD). Instead, the inorganic P fractionation analyses showed high levels of oxalate extractable P, Al, and Fe fractions (615-858, 1215-1478, and 337-752 mg kg-1, respectively), which were susceptible to slow release during the long-term (30-d) P desorption experiments at a moderately acidic soil pHwater. The labile P in the short-term (24-h) desorption studies was significantly associated with oxalate and F extractable Fe and Al, respectively. This was evident in an 80% reduction maximum in total desorbable P from NH4 oxalate/F pretreated soils. In the adsorption experiments, P was strongly retained in soils at near targeted pH of lime (???6.0), but P adsorption gradually decreased with decreasing pH near the soil pHwater (???5.0). The overall findings suggest that P losses from the can be suppressed by an increase in the P retention capacity of soils via (i) an increase in the number of lime applications to maintain soil pHwater at near targeted pH values, and/or (ii) alum/iron sulfate amendments to provide additional Al- and Fe-based adsorbents. ?? Soil Science Society of America.

EMP1, EMP 2, and EMP3 as novel therapeutic targets in human cancer.

PubMed

Wang, Yi-Wen; Cheng, Hong-Ling; Ding, Ya-Rou; Chou, Lien-Hsuan; Chow, Nan-Haw

2017-08-01

The epithelial membrane protein genes 1, 2, and 3 (EMP1, EMP2, and EMP3) belong to the peripheral myelin protein 22-kDa (PMP22) gene family, which consists of at least seven members: PMP22, EMP1, EMP2, EMP3, PERP, brain cell membrane protein 1, and MP20. This review addresses the structural and functional features of EMPs, detailing their tissue distribution and functions in the human body, their expression pattern in a variety of tumors, and highlighting the underlying mechanisms involved in carcinogenesis. The implications in cancer biology, patient prognosis prediction, and potential application in disease therapy are discussed. For example, EMP1 was reported to be a biomarker of gefitinib resistance in lung cancer and contributes to prednisolone resistance in acute lymphoblastic leukemia patients. EMP2 functions as an oncogene in human endometrial and ovarian cancers; however, characteristics of EMP2 in urothelial cancer fulfill the criteria of a suppressor gene. Of particular interest, EMP3 overexpression in breast cancer is significantly related to strong HER-2 expression. Co-expression of HER-2 and EMP3 is the most important indicator of progression-free and metastasis-free survival for patients with urothelial carcinoma of the upper urinary tract. Altogether, discovery of pharmacological inhibitors and/or regulators of EMP protein activity could open novel strategies for enhanced therapy against EMP-mediated human diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

Characterization of boron carbide with an electron microprobe

NASA Technical Reports Server (NTRS)

Matteudi, G.; Ruste, J.

1983-01-01

Within the framework of a study of heterogeneous materials (Matteudi et al., 1971: Matteudi and Verchery, 1972) thin deposits of boron carbide were characterized. Experiments using an electronic probe microanalyzer to analyze solid boron carbide or boron carbide in the form of thick deposits are described. Quantitative results on boron and carbon are very close to those obtained when applying the Monte Carlo-type correction calculations.

Role of the Emp Pilus Subunits of Enterococcus faecium in Biofilm Formation, Adherence to Host Extracellular Matrix Components, and Experimental Infection.

PubMed

Montealegre, Maria Camila; Singh, Kavindra V; Somarajan, Sudha R; Yadav, Puja; Chang, Chungyu; Spencer, Robert; Sillanpää, Jouko; Ton-That, Hung; Murray, Barbara E

2016-05-01

Enterococcus faecium is an important cause of hospital-associated infections, including urinary tract infections (UTIs), bacteremia, and infective endocarditis. Pili have been shown to play a role in the pathogenesis of Gram-positive bacteria, including E. faecium We previously demonstrated that a nonpiliated ΔempABC::cat derivative of E. faecium TX82 was attenuated in biofilm formation and in a UTI model. Here, we studied the contributions of the individual pilus subunits EmpA, EmpB, and EmpC to pilus architecture, biofilm formation, adherence to extracellular matrix (ECM) proteins, and infection. We identified EmpA as the tip of the pili and found that deletion of empA reduced biofilm formation to the same level as deletion of the empABC operon, a phenotype that was restored by reconstituting in situ the empA gene. Deletion of empB also caused a reduction in biofilm, while EmpC was found to be dispensable. Significant reductions in adherence to fibrinogen and collagen type I were observed with deletion of empA and empB, while deletion of empC had no adherence defect. Furthermore, we showed that each deletion mutant was significantly attenuated in comparison to the isogenic parental strain, TX82, in a mixed-inoculum UTI model (P < 0.001 to 0.048), that reconstitution of empA restored virulence in the UTI model, and that deletion of empA also resulted in attenuation in an infective endocarditis model (P = 0.0088). Our results indicate that EmpA and EmpB, but not EmpC, contribute to biofilm and adherence to ECM proteins; however, all the Emp pilins are important for E. faecium to cause infection in the urinary tract. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

The Association of Baseline and Longitudinal Change in Endothelial Microparticle Count with Mortality in Chronic Kidney Disease.

PubMed

Green, Darren; Skeoch, Sarah; Alexander, M Yvonne; Kalra, Philip A; Parker, Ben

2017-01-01

Chronic kidney disease (CKD) is associated with a unique milieu of vascular pathology, and effective biomarkers of active vascular damage are lacking. A candidate biomarker is the quantification of circulating endothelial microparticles (EMPs). This study observed baseline and longitudinal EMP change (δEMP) and established the association of these with all-cause mortality and cardiovascular events in CKD. An observational study in adults with CKD (estimated glomerular filtration rate [eGFR] <60 mL/min/1.73 m2). EMPs were quantified by flow cytometry of platelet poor plasma in 2 samples 12 months apart and categorised as EMP if AnnexinV+/CD31+/CD42b- EMPs were compared between primary renal diagnoses, and correlations between EMP/δEMP and other parameters made. Adjusted hazard ratios (HRs) for time to all-cause mortality and cardiovascular events were calculated for log-transformed EMP and δEMP using a Cox proportional hazard model. There were 123 patients (age 63 ± 11 years, systolic blood pressure 135 ± 18 mm Hg, eGFR 32 ± 16 mL/min/1.73 m2). The median baseline EMP count was 144/μL (range 10-714/μL). EMPs were numerically the highest in autosomal dominant polycystic kidney disease (253 [41-610]). An increase in urine protein:creatinine ratio was associated with an increase in EMP (co-efficient 0.21, p = 0.02). The adjusted HR for all-cause mortality for EMP was 8.20 (1.67-40.2, p = 0.01) and for δEMP was 2.69 (0.04-165, p = 0.64). There was no association between EMP or δEMP and cardiovascular events. Although EMP count was a significant marker of mortality risk, longitudinal change was not. This may reflect disease-specific EMP behaviour and the limitation of EMP as a generalised biomarker in CKD. © 2017 S. Karger AG, Basel.

High glucose condition increases NADPH oxidase activity in endothelial microparticles that promote vascular inflammation.

PubMed

Jansen, Felix; Yang, Xiaoyan; Franklin, Bernardo S; Hoelscher, Marion; Schmitz, Theresa; Bedorf, Jörg; Nickenig, Georg; Werner, Nikos

2013-04-01

Diabetes is a major risk factor for cardiovascular diseases. Circulating endothelial microparticles (EMP) are increased in diabetic patients, but their potential contribution in atherogenesis is unclear. We sought to determine the role of EMP derived under high glucose conditions in the development of atherosclerosis. EMP were generated from human coronary endothelial cells (HCAEC) exposed to high glucose concentrations in order to mimic diabetic conditions. These EMP were defined as 'injured' EMP (iEMP) and their effects were compared with EMP generated from 'healthy' untreated HCAEC. iEMP injection significantly impaired endothelial function in ApoE(-/-) mice compared with EMP and vehicle treatment. Immunofluorescent experiments showed increased macrophage infiltration and adhesion protein expression in atherosclerotic lesions of iEMP-treated ApoE(-/-) mice compared with controls. To further investigate the underlying mechanism of iEMP-induced vascular inflammation, additional in vitro experiments were performed. iEMP, but not EMP, induced activation of HCAEC in a time- and dose-dependent manner and increased monocyte adhesion. Further experiments demonstrated that iEMP induced activation of HCAEC by phosphorylation of p38 into its biologically active form phospho-p38. Inhibition of p38 activation abrogated iEMP-dependent induction of adhesion proteins and monocyte adhesion on HCAEC. Moreover, we could demonstrate that iEMP show increased NADPH oxidase activity and contain significantly higher level of reactive oxygen species (ROS) than EMP. iEMP triggered ROS production in HCAEC and thereby activate p38 in an ROS-dependent manner. High glucose condition increases NADPH oxidase activity in endothelial microparticles that amplify endothelial inflammation and impair endothelial function by promoting activation of the endothelium. These findings provide new insights into the pathogenesis of diabetes-associated atherosclerosis.

Determination of equilibrium electron temperature and times using an electron swarm model with BOLSIG+ calculated collision frequencies and rate coefficients

DOE PAGES

Pusateri, Elise N.; Morris, Heidi E.; Nelson, Eric M.; ...

2015-08-04

Electromagnetic pulse (EMP) events produce low-energy conduction electrons from Compton electron or photoelectron ionizations with air. It is important to understand how conduction electrons interact with air in order to accurately predict EMP evolution and propagation. An electron swarm model can be used to monitor the time evolution of conduction electrons in an environment characterized by electric field and pressure. Here a swarm model is developed that is based on the coupled ordinary differential equations (ODEs) described by Higgins et al. (1973), hereinafter HLO. The ODEs characterize the swarm electric field, electron temperature, electron number density, and drift velocity. Importantmore » swarm parameters, the momentum transfer collision frequency, energy transfer collision frequency, and ionization rate, are calculated and compared to the previously reported fitted functions given in HLO. These swarm parameters are found using BOLSIG+, a two term Boltzmann solver developed by Hagelaar and Pitchford (2005), which utilizes updated cross sections from the LXcat website created by Pancheshnyi et al. (2012). We validate the swarm model by comparing to experimental effective ionization coefficient data in Dutton (1975) and drift velocity data in Ruiz-Vargas et al. (2010). In addition, we report on electron equilibrium temperatures and times for a uniform electric field of 1 StatV/cm for atmospheric heights from 0 to 40 km. We show that the equilibrium temperature and time are sensitive to the modifications in the collision frequencies and ionization rate based on the updated electron interaction cross sections.« less

An SU-8-based microprobe with a nanostructured surface enhances neuronal cell attachment and growth

NASA Astrophysics Data System (ADS)

Kim, Eunhee; Kim, Jin-Young; Choi, Hongsoo

2017-12-01

Microprobes are used to repair neuronal injury by recording electrical signals from neuronal cells around the surface of the device. Following implantation into the brain, the immune response results in formation of scar tissue around the microprobe. However, neurons must be in close proximity to the microprobe to enable signal recording. A common reason for failure of microprobes is impaired signal recording due to scar tissue, which is not related to the microprobe itself. Therefore, the device-cell interface must be improved to increase the number of neurons in contact with the surface. In this study, we developed nanostructured SU-8 microprobes to support neuronal growth. Nanostructures of 200 nm diameter and depth were applied to the surface of microprobes, and the attachment and neurite outgrowth of PC12 cells on the microprobes were evaluated. Neuronal attachment and neurite outgrowth on the nanostructured microprobes were significantly greater than those on non-nanostructured microprobes. The enhanced neuronal attachment and neurite outgrowth on the nanostructured microprobes occurred in the absence of an adhesive coating, such as poly- l-lysine, and so may be useful for implantable devices for long-term use. Therefore, nanostructured microprobes can be implanted without adhesive coating, which can cause problems in vivo over the long term.

Microprobe monazite geochronology: new techniques for dating deformation and metamorphism

NASA Astrophysics Data System (ADS)

Williams, M.; Jercinovic, M.; Goncalves, P.; Mahan, K.

2003-04-01

High-resolution compositional mapping, age mapping, and precise dating of monazite on the electron microprobe are powerful additions to microstructural and petrologic analysis and important tools for tectonic studies. The in-situ nature and high spatial resolution of the technique offer an entirely new level of structurally and texturally specific geochronologic data that can be used to put absolute time constraints on P-T-D paths, constrain the rates of sedimentary, metamorphic, and deformational processes, and provide new links between metamorphism and deformation. New analytical techniques (including background modeling, sample preparation, and interference analysis) have significantly improved the precision and accuracy of the technique and new mapping and image analysis techniques have increased the efficiency and strengthened the correlation with fabrics and textures. Microprobe geochronology is particularly applicable to three persistent microstructural-microtextural problem areas: (1) constraining the chronology of metamorphic assemblages; (2) constraining the timing of deformational fabrics; and (3) interpreting other geochronological results. In addition, authigenic monazite can be used to date sedimentary basins, and detrital monazite can fingerprint sedimentary source areas, both critical for tectonic analysis. Although some monazite generations can be directly tied to metamorphism or deformation, at present, the most common constraints rely on monazite inclusion relations in porphyroblasts that, in turn, can be tied to the deformation and/or metamorphic history. Examples will be presented from deep-crustal rocks of northern Saskatchewan and from mid-crustal rocks from the southwestern USA. Microprobe monazite geochronology has been used in both regions to deconvolute overprinting deformation and metamorphic events and to clarify the interpretation of other geochronologic data. Microprobe mapping and dating are powerful companions to mass spectroscopic dating techniques. They allow geochronology to be incorporated into the microstructural analytical process, resulting in a new level of integration of time (t) into P-T-D histories.

Trace Element Zoning and Incipient Metamictization in a Lunar Zircon: Application of Three Microprobe Techniques

NASA Technical Reports Server (NTRS)

Wopenka, Brigitte; Jollife, Bradley L.; Zinner, Ernst; Kremser, Daniel T.

1996-01-01

We have determined major (Si, Zr, Hf), minor (Al, Y, Fe, P), and trace element (Ca, Sc, Ti, Ba, REE, Th, U) concentrations and Raman spectra of a zoned, 200 microns zircon grain in lunar sample 14161,7069, a quartz monzodiorite breccia collected at the Apollo 14 site. Analyses were obtained on a thin section in situ with an ion microprobe, an electron microprobe, and a laser Raman microprobe. The zircon grain is optically zoned in birefringence, a reflection of variable (incomplete) metamictization resulting from zo- nation in U and Th concentrations. Variations in the concentrations of U and Th correlate strongly with those of other high-field-strength trace elements and with changes in Raman spectral parameters. Concentrations of U and Th range from 21 to 55 ppm and 6 to 31 ppm, respectively, and correlate with lower Raman peak intensities, wider Raman peaks, and shifted Si-O peak positions. Concentrations of heavy rare earth elements range over a factor of three to four and correlate with intensities of fluorescence peaks. Correlated variations in trace element concentrations reflect the original magmatic differentiation of the parental melt approx. 4 b.y. ago. Degradation of the zircon structure, as reflected by the observed Raman spectral parameters, has occurred in this sample over a range of alpha-decay event dose from approx. 5.2 x 10(exp 14) to 1.4 x 10(exp 15) decay events per milligram of zircon, as calculated from the U and Th concentrations. This dose is well below the approx. 10(exp 16) events per milligram cumulative dose that causes complete metamictization and indicates that laser Raman microprobe spectroscopy is an analytical technique that is very sensitive to the radiation-induced damage in zircon.

High glucose increases the formation and pro-oxidative activity of endothelial microparticles.

PubMed

Burger, Dylan; Turner, Maddison; Xiao, Fengxia; Munkonda, Mercedes N; Akbari, Shareef; Burns, Kevin D

2017-09-01

Individuals with diabetes exhibit increases in circulating endothelial microparticles (eMPs, also referred to as endothelial microvesicles), which are associated with endothelial dysfunction and a heightened risk of cardiovascular complications. We have shown that eMPs are markers and mediators of vascular injury although their role in diabetes is unclear. We hypothesised that the composition and biological activity of eMPs are altered in response to high glucose exposure. We assessed the effects of high glucose on eMP formation, composition and signalling in cultured HUVECs. eMPs were isolated from the media of HUVECs cultured under conditions of normal glucose (eMP NG ), high glucose (eMP HG ) or osmotic control of L-glucose (eMP LG ). eMP size, concentration and surface charge were assessed by nanoparticle tracking analysis and flow cytometry. eMP protein composition was assessed by liquid chromatography-tandem mass spectrometry, and eMP-mediated effects on coagulation, reactive oxygen species (ROS) production and vessel function were assessed. Exposure of HUVECs to high glucose for 24 h caused a threefold increase in eMP formation, increased mean particle size (269 ± 18 nm vs 226 ± 11 nm) and decreased surface charge. Compared with eMP NG or eMP LG , eMP HG possessed approximately threefold greater pro-coagulant activity, stimulated HUVEC ROS production to a greater extent (~250% of eMP NG ) and were more potent inhibitors of endothelial-dependent relaxation. Proteomic analysis of eMPs identified 1212 independent proteins of which 68 were exclusively found in eMP HG . Gene ontology analysis revealed that eMP HG -exclusive proteins were associated with signalling pathways related to blood coagulation, cell signalling and immune cell activation. Our results indicate that elevated glucose is a potent stimulus for eMP formation that also alters their molecular composition leading to increased bioactivity. Such effects may contribute to progressive endothelial injury and subsequent cardiovascular complications in diabetes.

Arizona porphyry copper/hydrothermal deposits II: Crystal structure of ajoite, (K + Na)3Cu20Al3Si29O76(OH)16⋅∼8H2O

PubMed Central

Pluth, Joseph J.; Smith, Joseph V.

2002-01-01

A crystal from the type locality Ajo, AZ, yielded just enough intensity from streaked diffractions using synchrotron x-rays at the Advanced Photon Source to solve the crystal structure with composition (K + Na)3Cu20Al3Si29O76(OH)16⋅∼8H2O; triclinic, P1̄, a = 13.634(5) Å, b = 13.687(7), c = 14.522(7), α = 110.83(1)°, β = 107.21(1), γ = 105.68(1); refined to a final R = 12.5%. Electron microprobe analysis yielded a similar chemical composition that is slightly different from the combined chemical and electron microprobe analyses in the literature. The ajoite structure can be described as a zeolitic octahedral-tetrahedral framework that combines the alternate stacking of edge-sharing octahedral CuO6 layers and curved aluminosilicate layers and strings. Channels bounded by elliptical 12-rings and circular 8-rings of tetrahedra contain (K and Na) ions and water. The Al atoms occupy some of the Si tetrahedral sites. Each Cu atom has near-planar bonds to four oxygen atoms plus two longer distances that generate a distorted octahedron. Valence bond estimates indicate that 8 oxygen atoms of 46 are hydroxyl. Only one alkali atom was located in distorted octahedral coordination, and electron microprobe analyses indicate K and Na as major substituents. The water from chemical analysis presumably occurs as disordered molecules of zeolitic type not giving electron density from diffraction. The high R factor results from structural disorder and many weak intensities close to detection level. The crystal chemistry is compared with shattuckite, Cu5(SiO3)4(OH)2, and planchéite, Cu8Si8O22(OH)4⋅H2O, both found in oxidized copper deposits of Arizona but only the former directly with ajoite. PMID:12177404

Arizona porphyry copper/hydrothermal deposits II: crystal structure of ajoite, (K + Na)3Cu20Al3Si29O76(OH)16*~8H2O.

PubMed

Pluth, Joseph J; Smith, Joseph V

2002-08-20

A crystal from the type locality Ajo, AZ, yielded just enough intensity from streaked diffractions using synchrotron x-rays at the Advanced Photon Source to solve the crystal structure with composition (K + Na)3Cu20Al3Si29O76(OH)16* approximately 8H2O; triclinic, P1, a = 13.634(5) A, b = 13.687(7), c = 14.522(7), alpha = 110.83(1) degrees, beta = 107.21(1), gamma = 105.68(1); refined to a final R = 12.5%. Electron microprobe analysis yielded a similar chemical composition that is slightly different from the combined chemical and electron microprobe analyses in the literature. The ajoite structure can be described as a zeolitic octahedral-tetrahedral framework that combines the alternate stacking of edge-sharing octahedral CuO6 layers and curved aluminosilicate layers and strings. Channels bounded by elliptical 12-rings and circular 8-rings of tetrahedra contain (K and Na) ions and water. The Al atoms occupy some of the Si tetrahedral sites. Each Cu atom has near-planar bonds to four oxygen atoms plus two longer distances that generate a distorted octahedron. Valence bond estimates indicate that 8 oxygen atoms of 46 are hydroxyl. Only one alkali atom was located in distorted octahedral coordination, and electron microprobe analyses indicate K and Na as major substituents. The water from chemical analysis presumably occurs as disordered molecules of zeolitic type not giving electron density from diffraction. The high R factor results from structural disorder and many weak intensities close to detection level. The crystal chemistry is compared with shattuckite, Cu5(SiO3)4(OH)2, and planchéite, Cu8Si8O22(OH)4.H2O, both found in oxidized copper deposits of Arizona but only the former directly with ajoite.

Experimental determination of the partitioning of gallium between solid iron metal and synthetic basaltic melt Electron and ion microprobe study

NASA Technical Reports Server (NTRS)

Drake, M. J.; Newsom, H. E.; Reed, S. J. B.; Enright, M. C.

1984-01-01

The distribution of Ga between solid Fe metal and synthetic basaltic melt is investigated experimentally at temperatures of 1190 and 1330 C, and over a narrow range of oxygen fugacities. Metal-silicate reversal experiments were conducted, indicating a close approach to equilibrium. The analysis of the partitioned products was performed using electron and ion microprobes. At one bar total pressure, the solid metal/silicate melt partition coefficient D(Ga) is used to evaluate metal-silicate fractionation processes in the earth, moon, and Eucrite Parent Body (EPB). It is found that the depletion of Ga abundances in the EPB is due to the extraction of Ga into a metallic core. Likewise, the depletion of Ga in the lunar mantle is consistent with the extraction of Ga into a smaller lunar core if Ga was originally present in a subchondritic concentration. The relatively high Ga abundances in the earth's mantle are discussed, with reference to several theoretical models.

Bioimaging of cells and tissues using accelerator-based sources.

PubMed

Petibois, Cyril; Cestelli Guidi, Mariangela

2008-07-01

A variety of techniques exist that provide chemical information in the form of a spatially resolved image: electron microprobe analysis, nuclear microprobe analysis, synchrotron radiation microprobe analysis, secondary ion mass spectrometry, and confocal fluorescence microscopy. Linear (LINAC) and circular (synchrotrons) particle accelerators have been constructed worldwide to provide to the scientific community unprecedented analytical performances. Now, these facilities match at least one of the three analytical features required for the biological field: (1) a sufficient spatial resolution for single cell (< 1 mum) or tissue (<1 mm) analyses, (2) a temporal resolution to follow molecular dynamics, and (3) a sensitivity in the micromolar to nanomolar range, thus allowing true investigations on biological dynamics. Third-generation synchrotrons now offer the opportunity of bioanalytical measurements at nanometer resolutions with incredible sensitivity. Linear accelerators are more specialized in their physical features but may exceed synchrotron performances. All these techniques have become irreplaceable tools for developing knowledge in biology. This review highlights the pros and cons of the most popular techniques that have been implemented on accelerator-based sources to address analytical issues on biological specimens.

Stanford-USGS shrimp-RG ion microprobe: A new approach to determining the distribution of trace elements in coal

USGS Publications Warehouse

Kolker, A.; Wooden, J.L.; Persing, H.M.; Zielinski, R.A.

2000-01-01

The distribution of Cr and other trace metals of environmental interest in a range of widely used U.S. coals was investigated using the Stanford-USGS SHRIMP-RG ion microprobe . Using the oxygen ion source, concentrations of Cr (11 to 176 ppm), V (23 to 248 ppm), Mn (2 to 149 ppm), Ni (2 to 30 ppm), and 13 other elements were determined in illite/smectite, a group of clay minerals commonly present in coal. The results confirm previous indirect or semi-quantitative determinations indicating illite/smectite to be an important host of these metals. Calibration was achieved using doped aluminosilicate-glass synthetic standards and glasses prepared from USGS rock standards. Grains for analysis were identified optically, and confirmed by 1) precursory electron microprobe analysis and wavelength-dispersive compositional mapping, and 2) SHRIMP-RG major element data obtained concurrently with trace element results. Follow-up investigations will focus on the distribution of As and other elements that are more effectively ionized with the cesium primary beam currently being tested.

An ion microprobe study of the intra-crystalline behavior of REE and selected trace elements in pyroxene from mare basalts with different cooling and crystallization histories

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

Shearer, C.K.; Papike, J.J.; Simon, S.B.

1989-05-01

To study the effects of crystallization sequence and rate on trace element zoning characteristics of pyroxenes, the authors used combined electron microprobe-ion microprobe techniques on four nearly isochemical Apollo 12 and 15 pigeonite basalts with different cooling rates and crystallization histories. Major and minor element zoning characteristics are nearly identical to those reported in the literature. All the pyroxenes have similar chondrite-normalized REE patterns: negative Eu anomalies, positive slopes as defined by Yb/Ce, and slopes of REE patterns from Ce to Sm much steeper than from Gd to Yb. These trace element zoning characteristics in pyroxene and the partitioning ofmore » trace elements between pyroxene and the melt are intimately related to the interplay among the efficiency of the crystallization process, the kinetics at the crystal-melt interface, the kinetics of plagioclase nucleation and the characteristics of the crystal chemical substitutions within both the pyroxene and the associated crystallizing phases (i.e. plagioclase).« less

Endothelial microparticles-mediated transfer of microRNA-19b promotes atherosclerosis via activating perivascular adipose tissue inflammation in apoE-/- mice.

PubMed

Li, Changlong; Li, Sufang; Zhang, Feng; Wu, Manyan; Liang, Huizhu; Song, Junxian; Lee, Chongyou; Chen, Hong

2018-01-08

Microparticles(MPs) are the major carriers of circulating microRNAs. Our previous study has shown that microRNA (miR)-19b in endothelial cell-derived microparticles (EMPs) is significantly increased in patients with unstable angina. However, little is known about the relationship between miR-19b in EMPs and the progression of atherosclerosis. The aim of the present study was to define the role and potential mechanism of miR-19b incorporated in EMPs in the development of atherosclerosis. Western-diet-fed apoE -/- mice were injected with phosphate buffered solution(PBS), EMP carrying microRNA control(EMP control ) or miR-19b mimic (EMP miR19b ) intravenously. Systemic treatment with EMP miR19b significantly accelerated carotid artery atherosclerosis progression by increasing lipid, macrophages and smooth muscle cells and decreasing collagen content in atherosclerotic plaque. Fluorescence-labelled EMP miR19b injection proved that miR-19b could be transported into perivascular adipose tissue(PVAT) by EMPs. EMP miR19b treatment also promoted inflammatory cytokines secretion and macrophages infiltration in PVAT. In further experiment, apoE -/- mice were divided into 3 groups: EMP control PVAT(+), EMP miR19b PVAT(+) and EMP miR19b PVAT(-), based on removing or keeping pericarotid adipose tissue and injected with EMP control or EMP miR19b . Loss of PVAT attenuated EMP miR19b -mediated effects on increasing carotid atherosclerosis formation and inflammatory cytokines level in plaque. EMP miR19b inhibited suppressor of cytokine signaling 3 (SOCS3) expression in PVAT. Our findings demonstrate that miR-19b in EMPs exaggerates atherosclerosis progression by augmenting PVAT-specific inflammation proceeded by downregulating SOCS3 expression. Copyright © 2017 Elsevier Inc. All rights reserved.

Investigation of Synthetic Mg(1.3)V(1.7)O4 Spinel with MgO Inclusions: Case Study of a Spinel with an Apparently occupied Interstitial Site

NASA Technical Reports Server (NTRS)

Uchida, Hinako; Righter, Kevin; Lavina, Barbara; Nowell, Matthew M.; Wright, Stuart I.; Downs, Robert T.; Yang, Hexiong

2007-01-01

A magnesium vanadate spinel crystal, ideally MgV2O4, synthesized at 1 bar, 1200 C and equilibrated under FMQ + 1.3 log f(sub o2) condition, was investigated using single-crystal X-ray diffraction, electron microprobe, and electron backscatter (EBSD). The initial X-ray structure refinements gave tetrahedral and octahedral site occupancies, along with the presence of 0.053 apfu Mg at an interstitial octahedral site . Back-scattered electron (BSE) images and electron microprobe analyses revealed the existence of an Mg-rich phase in the spinel matrix, which was too small (less than or equal to 3microns) for an accurate chemical determination. The EBSD analysis combined with X-ray energy dispersive spectroscop[y (XEDS) suggested that the Mg-rich inclusions are periclase oriented coherently with the spinel matrix. The final structure refinements were optimized by subtracting the X-ray intensity contributions (approx. 9%) of periclase reflections, which eliminated the interstitial Mg. This study provides insight into possible origins of refined interstitial cations reported in the the literature for spinel, and points to the difficulty of using only X-ray diffraction data to distinguish a spinel with interstitial cations from one with coherently oriented MgO inclusions.

Endothelial microparticle uptake in target cells is annexin I/phosphatidylserine receptor dependent and prevents apoptosis.

PubMed

Jansen, Felix; Yang, Xiaoyan; Hoyer, Friedrich Felix; Paul, Kathrin; Heiermann, Nadine; Becher, Marc Ulrich; Abu Hussein, Nebal; Kebschull, Moritz; Bedorf, Jörg; Franklin, Bernardo S; Latz, Eicke; Nickenig, Georg; Werner, Nikos

2012-08-01

Endothelial microparticles (EMP) are released from activated or apoptotic cells, but their effect on target cells and the exact way of incorporation are largely unknown. We sought to determine the uptake mechanism and the biological effect of EMP on endothelial and endothelial-regenerating cells. EMP were generated from starved endothelial cells and isolated by ultracentrifugation. Caspase 3 activity assay and terminal deoxynucleotidyl transferase dUTP nick end labeling assay showed that EMP protect target endothelial cells against apoptosis in a dose-dependent manner. Proteomic analysis was performed to identify molecules contained in EMP, which might be involved in EMP uptake. Expression of annexin I in EMP was found and confirmed by Western blot, whereas the corresponding receptor phosphatidylserine receptor was present on endothelial target cells. Silencing either annexin I on EMP or phosphatidylserine receptor on target cells using small interfering RNA showed that the uptake of EMP by human coronary artery endothelial cells is annexin I/phosphatidylserine receptor dependent. Annexin I-downregulated EMP abrogated the EMP-mediated protection against apoptosis of endothelial target cells. p38 activation was found to mediate camptothecin-induced apoptosis. Finally, human coronary artery endothelial cells pretreated with EMP inhibited camptothecin-induced p38 activation. EMP are incorporated by endothelial cells in an annexin I/phosphatidylserine receptor-dependent manner and protect target cells against apoptosis. Inhibition of p38 activity is involved in EMP-mediated protection against apoptosis.

Preventing Electromagnetic Pulse Irradiation Damage on Testis Using Selenium-rich Cordyceps Fungi. A Preclinical Study in Young Male Mice.

PubMed

Miao, Xia; Wang, Yafeng; Lang, Haiyang; Lin, Yanyun; Guo, Qiyan; Yang, Mingjuan; Guo, Juan; Zhang, Yanjun; Zhang, Jie; Liu, Junye; Liu, Yaning; Zeng, Lihua; Guo, Guozhen

2017-02-01

Networked 21st century society, globalization, and communications technologies are paralleled by the rise of electromagnetic energy intensity in our environments and the growing pressure of the environtome on human biology and health. The latter is the entire complement of environmental factors, including the electromagnetic energy and the technologies that generate them, enacting on the digital citizen in the new century. Electromagnetic pulse (EMP) irradiation might have serious damaging effects not only on electronic equipment but also in the whole organism and reproductive health, through nonthermal effects and oxidative stress. We sought to determine whether EMP exposure (1) induces biological damage on reproductive health and (2) the extent to which selenium-rich Cordyceps fungi (daily coadministration) offer protection on the testicles and spermatozoa. In a preclinical randomized study, 3-week-old male BALB/c mice were repeatedly exposed to EMP (peak intensity 200 kV/m, pulse edge 3.5 ns, pulse width 15 ns, 0.1 Hz, and 400 pulses/day) 5 days per week for four consecutive weeks, with or without coadministration of daily selenium-rich Cordyceps fungi (100 mg/kg). Testicular index and spermatozoa formation were measured at baseline and 1, 7, 14, 28, and 60 day time points after EMP exposure. The group without Cordyceps cotreatment displayed decreased spermatozoa formation, shrunk seminiferous tubule diameters, and diminished antioxidative capacity at 28 and 60 days after exposure (p < 0.05). The Cordyceps daily cotreatment alleviated the testicular damage by EMP exposure, increased spermatozoa formation, and reduced apoptotic spermatogenic cells. These observations warrant further preclinical and clinical studies as an innovative approach for potential protection against electromagnetic radiation in the current age of networked society and digital citizenship.

Modeling of Army Research Laboratory EMP simulators

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

Miletta, J.R.; Chase, R.J.; Luu, B.B.

1993-12-01

Models are required that permit the estimation of emitted field signatures from EMP simulators to design the simulator antenna structure, to establish the usable test volumes, and to estimate human exposure risk. This paper presents the capabilities and limitations of a variety of EMP simulator models useful to the Army's EMP survivability programs. Comparisons among frequency and time-domain models are provided for two powerful US Army Research Laboratory EMP simulators: AESOP (Army EMP Simulator Operations) and VEMPS II (Vertical EMP Simulator II).

Elves and associated electron density changes due to cloud-to-ground and in-cloud lightning discharges

NASA Astrophysics Data System (ADS)

Marshall, R. A.; Inan, U. S.; Glukhov, V. S.

2010-04-01

A 3-D finite difference time domain model is used to simulate the lightning electromagnetic pulse (EMP) and its interaction with the lower ionosphere. Results agree with the frequently observed, doughnut-shaped optical signature of elves but show that the structure exhibits asymmetry due to the presence of Earth's ambient magnetic field. Furthermore, in-cloud (horizontal) lightning channels produce observable optical emissions without the doughnut shape and, in fact, produce a much stronger optical output for the same channel current. Electron density perturbations associated with elves are also calculated, with contributions from attachment and ionization. Results presented as a function of parameters such as magnetic field direction, dipole current orientation, altitude and amplitude, and ambient ionospheric density profile demonstrate the highly nonlinear nature of the EMP-ionosphere interaction. Ionospheric effects of a sequence of in-cloud discharges are calculated, simulating a burst of in-cloud lightning activity and resulting in large density changes in the overlying ionosphere.

Laboratory technology and cosmochemistry

PubMed Central

Zinner, Ernst K.; Moynier, Frederic; Stroud, Rhonda M.

2011-01-01

Recent developments in analytical instrumentation have led to revolutionary discoveries in cosmochemistry. Instrumental advances have been made along two lines: (i) increase in spatial resolution and sensitivity of detection, allowing for the study of increasingly smaller samples, and (ii) increase in the precision of isotopic analysis that allows more precise dating, the study of isotopic heterogeneity in the Solar System, and other studies. A variety of instrumental techniques are discussed, and important examples of discoveries are listed. Instrumental techniques and instruments include the ion microprobe, laser ablation gas MS, Auger EM, resonance ionization MS, accelerator MS, transmission EM, focused ion-beam microscopy, atom probe tomography, X-ray absorption near-edge structure/electron loss near-edge spectroscopy, Raman microprobe, NMR spectroscopy, and inductively coupled plasma MS. PMID:21498689

Electron-probe microanalysis of light elements in coal and other kerogen

USGS Publications Warehouse

Bustin, R.M.; Mastalerz, Maria; Raudsepp, M.

1996-01-01

Recent advances in electron microprobe technology including development of layered synthetic microstructures, more stable electronics and better matrix-correction programs facilitated routine microanalysis of the light elements in coal. Utilizing an appropriately equipped electron microprobe with suitable standards, it is now possible to analyze directly the light elements (C, O and N, if abundant) in coal macerals and other kerogen. The analytical results are both accurate compared to ASTM methods and highly precise, and provide an opportunity to access the variation in coal chemistry at the micrometre scale. Our experiments show that analyses using a 10 kV accelerating voltage and 10 nA beam current yield the most reliable data and result in minimum sample damage and contamination. High sample counts were obtained for C, O and N using a bi-elemental nickel-carbon pseudo-crystal (2d = 9.5 nm) as an analyzing crystal. Vitrinite isolated from anthracite rank coal proves the best carbon standard and is more desirable than graphite which has higher porosity, whereas lower rank vitrinite is too heterogeneous to use routinely as a standard. Other standards utilized were magnesite for oxygen and BN for nitrogen. No significant carbon, oxygen or nitrogen X-ray peak shifts or peak-shape changes occur between standards and the kerogen analyzed. Counting rates for carbon and oxygen were found to be constant over a range of beam sizes and currents for counting times up to 160 s. Probe-determined carbon and oxygen contents agree closely with those reported from ASTM analyses. Nitrogen analyses compare poorly to ASTM values which probably is in response to overlap between the nitrogen Ka peak with the carbon K-adsorption edge and the overall low nitrogen content of most of our samples. Our results show that the electron microprobe technique provides accurate compositional data for both minor and major elements in coal without the necessity and inherent problems associated with mechanically isolating macerals. Studies to date have demonstrated the level of compositional variability within and between macerals in suites of Canadian coals.

Erythro-myeloid progenitors can differentiate from endothelial cells and modulate embryonic vascular remodeling

PubMed Central

Kasaai, Bahar; Caolo, Vincenza; Peacock, Hanna M.; Lehoux, Stephanie; Gomez-Perdiguero, Elisa; Luttun, Aernout; Jones, Elizabeth A. V.

2017-01-01

Erythro-myeloid progenitors (EMPs) were recently described to arise from the yolk sac endothelium, just prior to vascular remodeling, and are the source of adult/post-natal tissue resident macrophages. Questions remain, however, concerning whether EMPs differentiate directly from the endothelium or merely pass through. We provide the first evidence in vivo that EMPs can emerge directly from endothelial cells (ECs) and demonstrate a role for these cells in vascular development. We find that EMPs express most EC markers but late EMPs and EMP-derived cells do not take up acetylated low-density lipoprotein (AcLDL), as ECs do. When the endothelium is labelled with AcLDL before EMPs differentiate, EMPs and EMP-derived cells arise that are AcLDL+. If AcLDL is injected after the onset of EMP differentiation, however, the majority of EMP-derived cells are not double labelled. We find that cell division precedes entry of EMPs into circulation, and that blood flow facilitates the transition of EMPs from the endothelium into circulation in a nitric oxide-dependent manner. In gain-of-function studies, we inject the CSF1-Fc ligand in embryos and found that this increases the number of CSF1R+ cells, which localize to the venous plexus and significantly disrupt venous remodeling. This is the first study to definitively establish that EMPs arise from the endothelium in vivo and show a role for early myeloid cells in vascular development. PMID:28272478

Emp is a component of the nuclear matrix of mammalian cells and undergoes dynamic rearrangements during cell division

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

Bala, Shashi; Kumar, Ajay; Soni, Shivani

2006-04-21

Emp, originally detected in erythroblastic islands, is expressed in numerous cell types and tissues suggesting a functionality not limited to hematopoiesis. To study the function of Emp in non-hematopoietic cells, an epitope-tagged recombinant human Emp was expressed in HEK cells. Preliminary studies revealed that Emp partitioned into both the nuclear and Triton X-100-insoluble cytoskeletal fractions in approximately a 4:1 ratio. In this study, we report investigations of Emp in the nucleus. Sequential extractions of interphase nuclei showed that recombinant Emp was present predominantly in the nuclear matrix. Immunofluorescence microscopy showed that Emp was present in typical nuclear speckles enriched withmore » the spliceosome assembly factor SC35 and partially co-localized with actin staining. Coimmunoprecipitation and GST-pull-down assays confirmed the apparent close association of Emp with nuclear actin. During mitosis, Emp was detected at the mitotic spindle/spindle poles, as well as in the contractile ring during cytokinesis. These results suggest that Emp undergoes dynamic rearrangements within the nuclear architecture that are correlated with cell division.« less

Emp is a component of the nuclear matrix of mammalian cells and undergoes dynamic rearrangements during cell division.

PubMed

Bala, Shashi; Kumar, Ajay; Soni, Shivani; Sinha, Sudha; Hanspal, Manjit

2006-04-21

Emp, originally detected in erythroblastic islands, is expressed in numerous cell types and tissues suggesting a functionality not limited to hematopoiesis. To study the function of Emp in non-hematopoietic cells, an epitope-tagged recombinant human Emp was expressed in HEK cells. Preliminary studies revealed that Emp partitioned into both the nuclear and Triton X-100-insoluble cytoskeletal fractions in approximately a 4:1 ratio. In this study, we report investigations of Emp in the nucleus. Sequential extractions of interphase nuclei showed that recombinant Emp was present predominantly in the nuclear matrix. Immunofluorescence microscopy showed that Emp was present in typical nuclear speckles enriched with the spliceosome assembly factor SC35 and partially co-localized with actin staining. Coimmunoprecipitation and GST-pull-down assays confirmed the apparent close association of Emp with nuclear actin. During mitosis, Emp was detected at the mitotic spindle/spindle poles, as well as in the contractile ring during cytokinesis. These results suggest that Emp undergoes dynamic rearrangements within the nuclear architecture that are correlated with cell division.

Requirement for erythroblast-macrophage protein (Emp) in definitive erythropoiesis.

PubMed

Soni, Shivani; Bala, Shashi; Hanspal, Manjit

2008-01-01

Emp, erythroblast-macrophage protein was initially identified as a mediator of erythroblast-macrophage interactions during erythroid differentiation. More recent studies have shown that targeted disruption of Emp leads to abnormal erythropoiesis in the fetal liver, and fetal demise. To further address the activity of Emp in the hematopoietic lineage in adult bone marrow, we conducted fetal liver HSC reconstitution assay. Emp null fetal liver cells were transplanted into lethally irradiated wild-type sibling mice, and assessed the erythropoietic activity. We found that Emp null cells rescued lethally irradiated mice with efficiency comparable to that of wild-type cells. However, the recipients of Emp null cells showed abnormal erythropoiesis as indicated by the presence of persistent anemia, extensive extramedullary erythropoiesis, and increased apoptosis of erythroid precursors. Extramedullary erythropoiesis suggests perturbed interactions between the Emp-deficient hematopoietic cells and the wild-type niche. Furthermore, in spleen colony-forming unit assays, proliferation rates of the Emp null cells were greater than those of the wild-type cells. Similarly, in vitro burst-forming unit-erythroid and colony-forming unit-erythroid assays showed increased erythroid colony numbers from Emp null livers. Morphologic examination showed that Emp null CFU-E-derived erythroblasts were immature compared to those derived from wild-type CFU-Es, suggesting that loss of Emp function in erythroid cells results in impaired proliferation and terminal differentiation. These results demonstrate that Emp plays a cell intrinsic role in the erythroid lineage.

Electromagnetic Spectrum Test and Evaluation Process

DTIC Science & Technology

2010-01-01

HERO , hazards of electromagnetic radiation to ordnance ; HERP, hazards of electromagnetic radiation to personnel; HERF, hazards of electromagnetic ... electromagnetic pulse (EMP); electronic protection; electrostatic dis- charge (ESD); hazards of electromagnetic radi- ation to personnel (HERP), ordnance ...including ordnance containing electrically initiated devices, to be mutually compatible in their intended

Very low frequency radio signatures of transient luminous events above thunderstorms

NASA Astrophysics Data System (ADS)

Marshall, Robert Andrew

Lightning discharges emit intense optical and acoustic energy, in the form of lightning and thunder, respectively, but a large amount of energy is emitted as radio-frequency electromagnetic pulses (EMP). These pulses can be detected thousands of kilometers away, thanks to efficient propagation in the waveguide formed by the conducting Earth and the overlying ionosphere. In addition, intense discharges interact with the overlying ionosphere at 80-100 km altitude. The EMP-ionosphere interaction is directly observed in one manifestation as the bright transient optical emissions known as "elves", but in addition, the interaction can directly modify the free electron density in the nighttime lower ionosphere. Modifications of the ionospheric electron density can be detected via subionospheric Very Low Frequency (VLF) remote sensing. In this method, coherent signals from powerful VLF transmitters, built for submarine communication and operated by the Navy, are monitored and their amplitude and phase are tracked in time. The variations of these signais are used to sense ionospheric modifications through rapid changes in the received amplitude and/or phase when the transmitted signal propagates through an ionospheric perturbation. When these perturbations are caused by lightning, they are known as "Early VLF" perturbations, due to the negligible delay between the lightning discharge and the appearance of the VLF signal change, whereas lightning-induced electron precipitation (LEP) events have a delay of 1--2 seconds. In this work, correlations between VLF signatures and optical events are used to show that these Early VLF events may be the signature of ionospheric modification by in-cloud (IC) lightning discharges. While the more impressive cloud-to-ground (CG) lightning discharges are more commonly observed and better understood, they are outnumbered in occurrence 3:1 by IC discharges, whose effects may be relatively stronger in the overlying ionosphere. We use a 3D time-domain model of the lightning EMP-ionosphere interaction to calculate expected ionospheric density changes from IC discharges. We find that bursts of IC-EMPs can significantly modify the lower ionosphere, with both increases and decreases in electron density. We then use a frequency-domain model of the VLF transmitter signal propagation in the Earth-ionosphere waveguide to a receiver to show that these density changes are consistent with measurements. Our results demonstrate that these Early VLF events, which are ubiquitous in VLF data, are signatures of the effects of in-cloud lightning, and that they can be used to quantify the effects of IC lightning on the ionosphere during an intense thunderstorm.

Interface effects in the dissolution of silicon into thin gold films

NASA Technical Reports Server (NTRS)

Sankur, H.; Mccaldin, J. O.

1975-01-01

The dissolution of crystalline Si and amorphous Si substrates into thin films of evaporated Au was studied with an electron microprobe and scanning electron microscopy. The dissolution pattern was found to be nonuniform along the plane of the surface and dependent on the crystalline orientation of the Si substrate. The dissolution is greatly facilitated when a very thin layer of Pd is evaporated between the Si substrate and the Au film.

Evanescent Microwave Probes on High-Resistivity Silicon and its Application in Characterization of Semiconductors

NASA Technical Reports Server (NTRS)

Tabib-Azar, M.; Akinwande, D.; Ponchak, George E.; LeClair, S. R.

1999-01-01

In this article we report the design, fabrication, and characterization of very high quality factor 10 GHz microstrip resonators on high-resistivity (high-rho) silicon substrates. Our experiments show that an external quality factor of over 13 000 can be achieved on microstripline resonators on high-rho silicon substrates. Such a high Q factor enables integration of arrays of previously reported evanescent microwave probe (EMP) on silicon cantilever beams. We also demonstrate that electron-hole pair recombination and generation lifetimes of silicon can be conveniently measured by illuminating the resonator using a pulsed light. Alternatively, the EMP was also used to nondestructively monitor excess carrier generation and recombination process in a semiconductor placed near the two-dimensional resonator.

Bioelectromagnetic effects of EMP: Preliminary findings

NASA Astrophysics Data System (ADS)

Aldrich, T. E.; Easterly, C. E.; Gailey, P. C.; Hamilton, C. B.

1988-06-01

Facilities to simulate electromagnetic pulses (EMPs) are used to test military equipment and electrical communications devices for resistance to the effects of an EMP caused by an upper-atmospheric nuclear detonation. The rapid rise time and high field strengths (0.1 to 50 kV/m) of an EMP distinguish it from other electromagnetic phenomena. Certain types of EMP simulators also expose facility operators and members of the public to electromagnetic fields of varying intensity as do other natural sources such as the fields produced near a lightning bolt. Limited biological effects data have been collected to assess the potential EMP health hazards to humans. Evidence from the available database does not establish that EMPs represent either an occupational or a public health hazard. A critique is presented of the EMP research published to date in order to explore its limitations and similarities with related outcome experience from other electromagnetic field research. Laboratory research and multiple years of observations on workers in existing EMP manufacturing and simulation facilities suggest that there are no acute or short-term health effects. The occupational exposure guideline for EMP is 100 kV/m, which is far in excess of usual exposures with EMP simulators.

Sirt6 mRNA-incorporated endothelial microparticles (EMPs) attenuates DM patient-derived EMP-induced endothelial dysfunction

PubMed Central

Jing, Tong; Ya-Shu, Kuang; Xue-Jun, Wang; Han-Jing, Hou; Yan, Lai; Yi-An, Yao; Fei, Chen; Xue-Bo, Liu

2017-01-01

Background Endothelial microparticles (EMPs) are small vesicles released by endothelial cells (ECs); they are considered biomarkers for endothelial dysfunction and therapeutic targets in diabetes-related vascular disease. Sirtuins have also been shown to play important roles in diabetes by regulating endothelial dysfunction. However, the effect of sirtuin-incorporated EMPs on their parental ECs remains unknown. Aim The present study aims to investigate the diagnostic value of EMPs in diabetes and detect the protective effects of sirtuin 6 (Sirt6) mRNA -incorporated EMPs on endothelial dysfunction. Methods EMPs were prepared from cultured HUVECs and venous blood from patients with diabetes (n=10) and from healthy volunteers (n=6) after sequential centrifugation. Adv-Sirt6 or Sirt6 siRNA was used to alter Sirt6 expression. EC angiogenesis, inflammatory phenotypes, nitric oxide (NO) formation and eNOS phosphorylation were used to evaluate endothelial dysfunction. Results The levels of EMPs in diabetic patients and high glucose-cultured HUVECs are high, whereas Sirt6 expression in plasma and EMPs is low. EMPs generated from diabetic patients or high glucose-cultured HUVECs increase inflammatory chemokine release and blunt EC angiogenesis. Furthermore, EMPs enriched with Sirt6 mRNA induces EC angiogenesis, increases eNOS phosphorylation and impedes inflammatory chemokine release. Inhibition of Sirt6 mRNA expression in EMPs by siRNA hinders angiogenesis and eNOS phosphorylation but increases cellular inflammation. Conclusion The Sirt6 mRNA-carrying EMPs may ameliorate endothelial dysfunction in diabetic patients. PMID:29371988

Sirt6 mRNA-incorporated endothelial microparticles (EMPs) attenuates DM patient-derived EMP-induced endothelial dysfunction.

PubMed

Jing, Tong; Ya-Shu, Kuang; Xue-Jun, Wang; Han-Jing, Hou; Yan, Lai; Yi-An, Yao; Fei, Chen; Xue-Bo, Liu

2017-12-26

Endothelial microparticles (EMPs) are small vesicles released by endothelial cells (ECs); they are considered biomarkers for endothelial dysfunction and therapeutic targets in diabetes-related vascular disease. Sirtuins have also been shown to play important roles in diabetes by regulating endothelial dysfunction. However, the effect of sirtuin-incorporated EMPs on their parental ECs remains unknown. The present study aims to investigate the diagnostic value of EMPs in diabetes and detect the protective effects of sirtuin 6 ( Sirt6 ) mRNA -incorporated EMPs on endothelial dysfunction. EMPs were prepared from cultured HUVECs and venous blood from patients with diabetes (n=10) and from healthy volunteers (n=6) after sequential centrifugation. Adv- Sirt6 or Sirt6 siRNA was used to alter Sirt6 expression. EC angiogenesis, inflammatory phenotypes, nitric oxide (NO) formation and eNOS phosphorylation were used to evaluate endothelial dysfunction. The levels of EMPs in diabetic patients and high glucose-cultured HUVECs are high, whereas Sirt6 expression in plasma and EMPs is low. EMPs generated from diabetic patients or high glucose-cultured HUVECs increase inflammatory chemokine release and blunt EC angiogenesis. Furthermore, EMPs enriched with Sirt6 mRNA induces EC angiogenesis, increases eNOS phosphorylation and impedes inflammatory chemokine release. Inhibition of Sirt6 mRNA expression in EMPs by siRNA hinders angiogenesis and eNOS phosphorylation but increases cellular inflammation. The Sirt6 mRNA -carrying EMPs may ameliorate endothelial dysfunction in diabetic patients.

Electron microprobe analysis program for biological specimens: BIOMAP

NASA Technical Reports Server (NTRS)

Edwards, B. F.

1972-01-01

BIOMAP is a Univac 1108 compatible program which facilitates the electron probe microanalysis of biological specimens. Input data are X-ray intensity data from biological samples, the X-ray intensity and composition data from a standard sample and the electron probe operating parameters. Outputs are estimates of the weight percentages of the analyzed elements, the distribution of these estimates for sets of red blood cells and the probabilities for correlation between elemental concentrations. An optional feature statistically estimates the X-ray intensity and residual background of a principal standard relative to a series of standards.

Structures of the carbohydrate recognition domain of Ca2+-independent cargo receptors Emp46p and Emp47p.

PubMed

Satoh, Tadashi; Sato, Ken; Kanoh, Akira; Yamashita, Katsuko; Yamada, Yusuke; Igarashi, Noriyuki; Kato, Ryuichi; Nakano, Akihiko; Wakatsuki, Soichi

2006-04-14

Emp46p and Emp47p are type I membrane proteins, which cycle between the endoplasmic reticulum (ER) and the Golgi apparatus by vesicles coated with coat protein complexes I and II (COPI and COPII). They are considered to function as cargo receptors for exporting N-linked glycoproteins from the ER. We have determined crystal structures of the carbohydrate recognition domains (CRDs) of Emp46p and Emp47p of Saccharomyces cerevisiae, in the absence and presence of metal ions. Both proteins fold as a beta-sandwich, and resemble that of the mammalian ortholog, p58/ERGIC-53. However, the nature of metal binding is distinct from that of Ca(2+)-dependent p58/ERGIC-53. Interestingly, the CRD of Emp46p does not bind Ca(2+) ion but instead binds K(+) ion at the edge of a concave beta-sheet whose position is distinct from the corresponding site of the Ca(2+) ion in p58/ERGIC-53. Binding of K(+) ion to Emp46p appears essential for transport of a subset of glycoproteins because the Y131F mutant of Emp46p, which cannot bind K(+) ion fails to rescue the transport in disruptants of EMP46 and EMP47 genes. In contrast the CRD of Emp47p binds no metal ions at all. Furthermore, the CRD of Emp46p binds to glycoproteins carrying high mannosetype glycans and the is promoted by binding not the addition of Ca(2+) or K(+) ion in These results suggest that Emp46p can be regarded as a Ca(2+)-independent intracellular lectin at the ER exit sites.

Epithelial Membrane Protein-2 in Human Proliferative Vitreoretinopathy and Epiretinal Membranes.

PubMed

Telander, David G; Yu, Alfred K; Forward, Krisztina I; Morales, Shawn A; Morse, Lawrence S; Park, Susanna S; Gordon, Lynn K

2016-06-01

To determine the level of epithelial membrane protein-2 (EMP2) expression in preretinal membranes from surgical patients with proliferative vitreoretinopathy (PVR) or epiretinal membranes (ERMs). EMP2, an integrin regulator, is expressed in the retinal pigment epithelium and understanding EMP2 expression in human retinal disease may help determine whether EMP2 is a potential therapeutic target. Preretinal membranes were collected during surgical vitrectomies after obtaining consents. The membranes were fixed, processed, sectioned, and protein expression of EMP2 was evaluated by immunohistochemistry. The staining intensity (SI) and percentage of positive cells (PP) in membranes were compared by masked observers. Membranes were categorized by their cause and type including inflammatory and traumatic. All of the membranes stained positive for EMP2. Proliferative vitreoretinopathy-induced membranes (all causes) showed greater expression of EMP2 than ERMs with higher SI (1.81 vs. 1.38; P = 0.07) and PP (2.08 vs. 1.54; P = 0.09). However all the PVR subgroups had similar levels of EMP2 expression without statistically significant differences by Kruskal-Wallis test. Inflammatory PVR had higher expression of EMP2 than ERMs (SI of 2.58 vs. 1.38); however, this was not statistically significant. No correlation was found between duration of PVR membrane and EMP2 expression. EMP2 was detected by RT-PCR in all samples (n = 6) tested. All studied ERMs and PVR membranes express EMP2. Levels of EMP2 trended higher in all PVR subgroups than in ERMs, especially in inflammatory and traumatic PVR. Future studies are needed to determine the role of EMP2 in the pathogenesis and treatment of various retinal conditions including PVR.

A randomized phase II trial of personalized peptide vaccine plus low dose estramustine phosphate (EMP) versus standard dose EMP in patients with castration resistant prostate cancer.

PubMed

Noguchi, Masanori; Kakuma, Tatsuyuki; Uemura, Hirotsugu; Nasu, Yasutomo; Kumon, Hiromi; Hirao, Yasuhiko; Moriya, Fukuko; Suekane, Shigetaka; Matsuoka, Kei; Komatsu, Nobukazu; Shichijo, Shigeki; Yamada, Akira; Itoh, Kyogo

2010-07-01

Personalized peptide vaccination (PPV) combined with chemotherapy could be a novel approach for many cancer patients. In this randomized study, we evaluated the anti-tumor effect and safety of PPV plus low-dose estramustine phosphate (EMP) as compared to standard-dose EMP for HLA-A2- or -A24-positive patients with castration resistant prostate cancer. Patients were randomized into groups receiving either PPV plus low-dose EMP (280 mg/day) or standard-dose EMP (560 mg/day). After disease progression, patients were switched to the opposite regime. The primary end point was progression-free survival (PFS). We randomly assigned 28 patients to receive PPV plus low-dose EMP and 29 patients to receive standard-dose EMP. Nineteen events in the PPV group and 20 events in the EMP group occurred during the first treatment. Median PFS for the first treatment was 8.5 months in the PPV group and 2.8 months in the EMP group with a hazard ratio (HR) of 0.28 (95% CI, 0.14-0.61; log-rank P = 0.0012), while there was no difference for median PFS for the second treatment. The HR for overall survival was 0.3 (95% CI, 0.1-0.91) in favor of the PPV plus low-dose EMP group (log-rank, P = 0.0328). The PPV plus low-dose EMP was well tolerated without major adverse effects and with increased levels of IgG and cytotoxic-T cell responses to the vaccinated peptides. PPV plus low-dose EMP was associated with an improvement in PSA-based PFS as compared to the standard-dose EMP alone.

EMP Design Guidelines for Naval Ship Systems

DTIC Science & Technology

1975-08-22

le xc Ci .ube irret i Type FXC it LA 38 Beads 4 * 1 svj- I * 1 1 \\ Measured 3( )0 Beads V i i V 30 Bead 1 s...ATTN: R. W. Rostrom RCA Corporation Government & Commercial Systems Astro Electronics Division P. 0. Box 800 Princeton, New Jersey 08540 ATTN

The Perils of Electron Microprobe Analysis of Apatite

NASA Astrophysics Data System (ADS)

Henderson, C. E.; Essene, E. J.; Wang, K. L.; Zhang, Y.

2010-12-01

Accurate electron microprobe analysis of apatite is problematic, especially for F and Cl, whose concentrations are essential in calculating a non-analyzable OH component. The issues include beam-induced sample damage and temporal variation of F and Cl X-rays; both effects are mainly dependent on beam current, beam spot size and apatite orientation [1]. To establish a rigorous analytical procedure, several oriented apatite samples, including the well-known Durango and Wilberforce fluorapatites, were analyzed for a large suite of elements, including oxygen. Careful X-ray spectroscopy was performed, including selection of appropriate analytical standards, background measurement positions and comparison of area peak factors. Polarized infrared spectra on oriented apatite samples were also collected for complementary information. The results show that when apatite samples are oriented with the c-axis parallel to the electron beam, there is significant nonlinear variation (an increase or decrease, depending on measurement conditions) of F and Cl X-ray intensities during analyses, and systematically higher-than-expected F apparent concentrations, despite the careful selection of electron beam conditions from a series of X-ray time scans and zero-time count rate extrapolation. On the other hand, when the electron beam is oriented perpendicular to the c-axis, with a ≤ 15 nA beam current and a ≥ 5 µm diameter defocused beam, F and Cl X-ray intensities do not vary or vary slowly and predictably with time, yielding quantitative analysis results for the Durango and Wilberforce apatites (both containing little OH) which are in good agreement with published wet chemical analyses. Furthermore, the OH and CO2 contents inferred for three other analyzed apatite samples are roughly consistent with infrared analyses. For example, for an apatite from Silver Crater Mine in Ontario, significant deficiency in the P site, as well as extra F, was inferred from microprobe analyses. Infrared spectra show a strong band of (CO3)2- for this apatite, which indicates a possible substitution of (CO3)2-(F)- for (PO4)3-. Other techniques to mitigate temporal variation of F and Cl, including alternative metal coatings, concurrent stage movement, and cryogenic sample-cooling were attempted, but did not eliminate the disparity in measured F concentrations between the two sample orientations. Thus, we believe that F measurements on F-rich apatite samples of unknown orientation are immediately suspect and should be regarded as upper limits of true F concentration. X-ray mapping, CL imaging and subsequent quantitative analyses show compositional variations in Na, S, Si, and REE in the Durango and Wilberforce fluorapatite samples used in this study. Problems of electron beam sensitivity, X-ray intensity anisotropy due to sample orientation, and compositional heterogeneity call into question their continued use as routine microanalysis reference materials. Microanalysts are encouraged to use more robust calibration standards, such as Cl-rich or other F-poor apatites for Ca, P, O and Cl, and MgF2 for F measurements. [1] Stormer, J.C., Pierson, M.L, and Tacker, R.C. (1993) Variation of F and Cl X-ray intensity due to anisotropic diffusion in apatite during electron microprobe analysis. Am. Min., 78, 641-648.

Release of endothelial microparticles in patients with arterial hypertension, hypertensive emergencies and catheter-related injury.

PubMed

Sansone, Roberto; Baaken, Maximilian; Horn, Patrick; Schuler, Dominik; Westenfeld, Ralf; Amabile, Nicolas; Kelm, Malte; Heiss, Christian

2018-06-01

Circulating endothelial microparticles (EMPs) are increased in arterial hypertension. The role of physicomechanical factors that may induce EMP release in vivo is still unknown. We studied the relationship of EMPs and physicomechanical factors in stable arterial hypertension and hypertensive emergencies, and investigated the pattern of EMP release after mechanical endothelial injury. In a pilot study, 41 subjects (50% hypertensives) were recruited. EMPs were discriminated by flow-cytometry (CD31 + /41 - , CD62e + , CD144 + ). Besides blood pressure measurements, pulse-wave-analysis was performed. Flow-mediated dilation (FMD), nitroglycerin-mediated dilation (NMD), and wall-shear-stress (WSS) were measured ultrasonographically in the brachial artery; microvascular perfusion by laser-Doppler (Clinicaltrials.gov: NCT02795377). We studied patients with hypertensive emergencies before and 4 h after BP lowering by urapidil (n = 12) and studied the release of EMPs due to mechanical endothelial injury after coronary angiography (n = 10). Hypertensives exhibited increased EMPs (CD31 + /41 - , CD144 + , CD62e + ) as compared to normotensives and EMPs univariately correlated with systolic BP (SBP), augmentation index, and pulse wave velocity and inversely with FMD. CD31 + /41 - -EMPs correlated with diameter and inversely with WSS and NMD. CD62e + and CD144 + -EMPs inversely correlated with microvascular function. During hypertensive emergency, only CD62e + and CD144 + -EMPs were further elevated and FMD was decreased compared to stable hypertensives. Blood pressure lowering decreased CD62e + and CD144 + -EMPs and increased FMD. CD31 + /41 - EMPs, diameter, and WSS remained unaffected. Similar to hypertensive emergency, catheter-related endothelial injury increased only CD144 + and CD62e + -EMPs. EMP release in hypertension is complex and may involve both physicomechanical endothelial injury and activation (CD144 + , CD62e + ) and decreased wall shear stress (CD31 + /41 - ). Copyright © 2018 Elsevier B.V. All rights reserved.

MnSOD expression inhibited by electromagnetic pulse radiation in the rat testis.

PubMed

Zeng, LiHua; Ji, XiTuan; Zhang, YanJun; Miao, Xia; Zou, ChangXu; Lang, HaiYang; Zhang, Jie; Li, YuRong; Wang, XiaoWu; Qi, HongXing; Ren, DongQin; Guo, GuoZhen

2011-12-01

Male Sprague Dawley rats were exposed to EMP irradiation of 100 kV/m peak-to-peak e-field intensity and different numbers of pulses. Rat sperm samples were prepared for analysis of sperm qualities; Testes were assessed by transmission electron microscopy and serum hormone concentrations were examined by radioimmunoassay; Enzymatic activities of Total-superoxide dismutase(T-SOD) and manganese-superoxide dismutase (MnSOD), the mRNA levels of MnSOD and cuprozinc-superoxide dismutase (CuZnSOD), and the density of malondialdehyde (MDA) were also determined. EMP irradiation did not affect spermatozoon morphology, micronucleus formation rate, sperm number or viability, but the acrosin reaction rate decreased at 24 h and 48 h and recovered by 72 h after irradiation as compared to the controls. The ultrastructure of rat testis displayed more serious damage at 24 h than at other time points (6 h, 12 h, 48 h). Serum levels of luteotrophic hormone (LH) and testosterone (T) were elevated in irradiated rats as compared to controls. After irradiation, enzymatic activities of T-SOD and MnSOD were reduced by 24 h, consistent with the changes observed in MnSOD mRNA expression; MDA content increased at 6 h in turn. These studies have quantified the morphological damage and dysfunction in the rat reproductive system induced by EMP. The mechanism of EMP induced damage may be associated with the inhibition of MnSOD expression.

Effects of electromagnetic pulse on serum element levels in rat.

PubMed

Li, Kangchu; Ma, Shirong; Ren, Dongqing; Li, Yurong; Ding, Guirong; Liu, Junye; Guo, Yao; Guo, Guozhen

2014-04-01

Electromagnetic pulse (EMP) was a potentially harmful factor to the human body, and a biological dosimetry to evaluate effects of EMP is necessary. Little is known about effects of EMP on concentration of macro and trace elements in serum so far. In this study, Sprague-Dawley rats were randomly divided into 50-kV/m EMP-exposed group (n = 10), 100-kV/m EMP-exposed group (n = 10), 200-kV/m EMP-exposed group (n = 40), and the sham-exposed group (n = 20). The macro and trace element concentrations in serum were examined at 6, 12, 24, and 48 h after EMP exposure at different electric field intensities. Compared with the sham-exposed groups, the concentration of sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), zinc (Zn), copper (Cu), iron (Fe), selenium (Se), and manganese (Mn) in rat serum was not changed significantly within 48 h after 200 pulses of EMP exposure at electric field intensity of 50, 100, and 200 kV/m although the K level was decreased and the Ca level was increased with the electric field intensity of EMP increasing. In addition, there was a tendency that the Zn level was decreased with the time going on within 48 h after EMP exposure. Under our experimental conditions, EMP exposure cannot affect the concentration of macro and trace elements in rat serum. There was no time-effect or dose-effect relationship between EMP exposure and serum element levels. The macro and trace elements in serum are not suitable endpoints of biological dosimetry of EMP.

The radiated electromagnetic field from collimated gamma rays and electron beams in air

NASA Astrophysics Data System (ADS)

Tumolillo, T. A.; Wondra, J. P.; Hobbs, W. E.; Smith, K.

1980-12-01

Nuclear weapons effects computer codes are used to study the electromagnetic field produced by gamma rays or by highly relativistic electron beams moving through the air. Consideration is given to large-area electron and gamma beams, small-area electron beams, variation of total beam current, variation of pressure in the beam channel, variation of the beam rise time, variation of beam radius, far-field radiated signals, and induced current on a system from a charged-particle beam. The work has application to system EMP coupling from nuclear weapons or charged-particle-beam weapons.

EMP2 regulates angiogenesis in endometrial cancer cells through induction of VEGF

PubMed Central

Gordon, L K; Kiyohara, M; Fu, M; Braun, J; Dhawan, P; Chan, A; Goodglick, L; Wadehra, M

2013-01-01

Understanding tumor-induced angiogenesis is a challenging problem with important consequences for the diagnosis and treatment of cancer. In this study, we define a novel function for epithelial membrane protein-2 (EMP2) in the control of angiogenesis. EMP2 functions as an oncogene in endometrial cancer, and its expression has been linked to decreased survival. Using endometrial cancer xenografts, modulation of EMP2 expression resulted in profound changes to the tumor microvasculature. Under hypoxic conditions, upregulation of EMP2 promoted vascular endothelial growth factors (VEGF) expression through a HIF-1α-dependent pathway and resulted in successful capillary-like tube formation. In contrast, reduction of EMP2 correlated with reduced HIF-1α and VEGF expression with the net consequence of poorly vascularized tumors in vivo. We have previously shown that targeting of EMP2 using diabodies in endometrial cancer resulted in a reduction of tumor load, and since then we have constructed a fully human EMP2 IgG1. Treatment of endometrial cancer cells with EMP2-IgG1 reduced tumor load with a significant improvement in survival. These results support the role of EMP2 in the control of the tumor microenvironment and confirm the cytotoxic effects observed by EMP2 treatment in vivo. PMID:23334331

Changing pattern of the subcellular distribution of erythroblast macrophage protein (Emp) during macrophage differentiation.

PubMed

Soni, Shivani; Bala, Shashi; Kumar, Ajay; Hanspal, Manjit

2007-01-01

Erythroblast macrophage protein (Emp) mediates the attachment of erythroid cells to macrophages and is required for normal differentiation of both cell lineages. In erythroid cells, Emp is believed to be involved in nuclear extrusion, however, its role in macrophage differentiation is unknown. Information on the changes in the expression level and subcellular distribution of Emp in differentiating macrophages is essential for understanding the function of Emp. Macrophages of varying maturity were examined by immunofluorescence microscopy and biochemical methods. Our data show that Emp is expressed in all stages of maturation, but its localization pattern changes dramatically during maturation: in immature macrophages, a substantial fraction of Emp is associated with the nuclear matrix, whereas in more mature cells, Emp is expressed largely at cell surface. Pulse-chase experiments show that nascent Emp migrates intracellularly from the cytoplasm to the plasma membrane more efficiently in mature macrophages than in immature cells. Incubation of erythroid cells with macrophages in culture shows that erythroid cells attach to mature macrophages but not to immature macrophage precursors. Together, our data show that the temporal and spatial expression of Emp correlates with its role in erythroblastic island formation and suggest that Emp may be involved in multiple cellular functions.

*CHANGING PATTERN OF THE SUBCELLULAR DISTRIBUTION OF ERYTHROBLAST MACROPHAGE PROTEIN (EMP) DURING MACROPHAGE DIFFERENTIATION

PubMed Central

Soni, Shivani; Bala, Shashi; Kumar, Ajay; Hanspal, Manjit

2007-01-01

Erythroblast macrophage protein (Emp), mediates the attachment of erythroid cells to macrophages, and is required for normal differentiation of both cell lineages. In erythroid cells Emp is believed to be involved in nuclear extrusion however, its role in macrophage differentiation is unknown. Information on the changes in the expression level and subcellular distribution of Emp in differentiating macrophages is essential for understanding the function of Emp. Macrophages of varying maturity were examined by immunofluorescence microscopy and biochemical methods. Our data shows that Emp is expressed in all stages of maturation, but its localization pattern changes dramatically during maturation: in immature macrophages, a substantial fraction of Emp is associated with the nuclear matrix, whereas in more mature cells, Emp is expressed largely at cell surface. Pulse-chase experiments show that nascent Emp migrates intracellularly from the cytoplasm to the plasma membrane more efficiently in mature macrophages than in immature cells. Incubation of erythroid cells with macrophages in culture show that erythroid cells attach to mature macrophages but not to immature macrophage precursors. Together, our data shows that the temporal and spatial expression of Emp correlates with its role in erythroblastic island formation, and suggests that Emp may be involved in multiple cellular functions. PMID:17071116

Planar defects as Ar traps in trioctahedral micas: A mechanism for increased Ar retentivity in phlogopite

NASA Astrophysics Data System (ADS)

Camacho, A.; Lee, J. K. W.; Fitz Gerald, J. D.; Zhao, J.; Abdu, Y. A.; Jenkins, D. M.; Hawthorne, F. C.; Kyser, T. K.; Creaser, R. A.; Armstrong, R.; Heaman, L. W.

2012-08-01

The effects of planar defects and composition on Ar mobility in trioctahedral micas have been investigated in samples from a small marble outcrop (∼500 m2) in the Frontenac Terrane, Grenville Province, Ontario. These micas crystallized during amphibolite-facies metamorphism at ∼1170 Ma and experienced a thermal pulse ∼100 Ma later at shallow crustal levels associated with the emplacement of plutons. 87Rb/86Sr ages of the phlogopites range from ∼950 to ∼1050 Ma, consistent with resetting during the later thermal event. The same phlogopites however, give 40Ar/39Ar ages between ∼950 and 1160 Ma, spanning the age range of the two thermal events. This result is intriguing because these micas have undergone the same thermal history and were not deformed after peak metamorphic conditions. In order to understand this phenomenon, the chemical, crystallographical, and microstructural nature of four mica samples has been characterized in detail using a wide range of analytical techniques. The scanning electron microscope (SEM), electron microprobe (EMP), and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) data show that the micas are chemically homogeneous (with the exception of Ba) and similar in composition. The Fourier transform infrared spectroscopy and Mossbauer results show that the M sites for three of the micas are dominated by divalent cations and the Fe3+/(Fe2++Fe3+) ratio for all four phlogopites ranges from 0.10 to 0.25. The stable-isotopic data for calcite indicate that this outcrop was not affected by hydrothermal fluids after peak metamorphism. No correlation between chemical composition and 87Rb/86Sr and 40Ar/39Ar age or between crystal size and 40Ar/39Ar age is observed. The only major difference among all of the micas was revealed through transmitted electron microscope (TEM), which shows that the older 1M micas contain significantly more layer stacking defects, associated with crystallization, than the younger micas. We propose that these defect structures, which are enclosed entirely within the mineral grain may serve as Ar traps and effectively increase the Ar retentivity of the mineral. As this phenomenon has not been previously documented in micas, this may have significant implications for the interpretation of 40Ar/39Ar ages of minerals which have similar defect structures.

Measurement of Ti[superscript +3] / Ti[superscript +4] ratios in pyroxene in Wark-Loveing rims: Evidence for formation in a reducing solar nebula

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

Simon, S.B.; Sutton, S.R.; Grossman, L.

2006-12-13

Ti-bearing clinopyroxene, known as fassaite, is a major phase in the interiors of coarse-grained, Ca-, Al-rich refractory inclusions (CAIs). Electron microprobe (EMP) analyses of such pyroxene yield low cation sums when normalized to six oxygen anions if it is assumed that all Ti is present as Ti{sup 4+}. Instead, we can assume that there is one Ca cation [1] and two tetrahedral cations present per six oxygens, and can then calculate a Ti{sup 3+}/(Ti{sup 3+} + Ti{sup 4+}), or Ti{sup 3+}/Ti{sup tot}, ratio that gives exactly one cation in the remaining site and a total of exactly four cations permore » six oxygens. Additional evidence for the presence of Ti in multiple valence states includes: pleochroism in Ti-rich crystals with negligible amounts of other multivalent elements; results from measurements of optical spectra [2]; and X-ray absorption near-edge structure (XANES) analysis [3]. Calculation of accurate Ti{sup 3+}/Ti{sup tot} ratios from EMP analyses is generally limited to analyses with >4 wt% TiO{sub 2}{sup tot} (all Ti as TiO{sub 2}), because at low Ti contents the analytical uncertainties approach the magnitude of the cation deficit caused by assuming all Ti is Ti{sup 4+}. Many refractory inclusions are enclosed in sequences of mineralogically distinct layers, first described by [4], that must have formed after the host inclusions did. In most cases, from the CAI outward, the sequence consists of a layer of spinel {+-} perovskite; voids, melilite, or alteration products; clinopyroxene; and hedenbergite. The pyroxene layer may be immediately adjacent to spinel and is commonly zoned from Ti-rich fassaite nearest the spinel layer to Ti-poor aluminous diopside over distances of {approx}10 {micro}m [4]. A recent study of the pyroxene in the rims of one Allende and two Leoville inclusions [5] found that most points analyzed by electron probe had between 4 and 7 wt% TiO{sub 2}{sup tot} and 0.7-1.7 wt% FeO. Those authors also found < 1 Ca cation, but very close to 4 total cations, per 6 oxygen ions, and therefore little or no Ti{sup 3+}. They kindly loaned us one of their samples for analysis, and we also found low Ca contents, high FeO contents ({approx}1 wt%) and undetectable to low Ti{sup 3+} contents compared to fassaite found in the interiors of CAIs. The low-Ca analyses would seem to reflect the presence of an enstatite component in addition to the standard fassaite components [1], but despite inclusion of such a component in our calculations we have not been able to satisfactorily resolve the analyses into pyroxene endmembers. This is a hint that pyroxene analysis spots are contaminated with another phase, a serious problem for stoichiometrydependent calculation of Ti{sup 3+}/Ti{sup tot} ratios. We need to know whether or not rim pyroxene contains Ti{sup 3+} because of its importance as a recorder of nebular oxygen fugacity, but we are unsure of how to normalize EMP analyses in this case, so we cannot calculate Ti{sup 3+}/Ti{sup tot} accurately. We therefore decided to measure the Ti{sup 3+}/Ti{sup tot} of rim pyroxene directly, by XANES. We have conducted a detailed study of pyroxene in the rim on TS24, a fluffy Type A inclusion from Allende. This inclusion is large and very irregularly shaped, giving it a relatively high surface area. It has a well-developed rim sequence, from the CAI outward, of spinel, clinopyroxene zoned from Ti-, Al-rich to nearly pure diopside over {approx}20 {micro}m, and hedenbergite. The spinel-pyroxene and diopside-hedenbergite contacts are sharp.« less

Epithelial Membrane Protein-2 is a Novel Therapeutic Target in Ovarian Cancer

PubMed Central

Fu, Maoyong; Maresh, Erin L.; Soslow, Robert A.; Alavi, Mohammad; Mah, Vei; Zhou, Qin; Iasonos, Alexia; Goodglick, Lee; Gordon, Lynn K.; Braun, Jonathan; Wadehra, Madhuri

2010-01-01

Purpose The tetraspan protein epithelial membrane protein-2 (EMP2) has been shown to regulate the surface display and signaling from select integrin pairs, and it was recently identified as a prognostic biomarker in human endometrial cancer. In this study, we assessed the role of EMP2 in human ovarian cancer. Experimental Design We examined the expression of EMP2 within a population of women with ovarian cancer using tissue microarray assay technology. We evaluated the efficacy of EMP2-directed antibody therapy using a fully human recombinant bivalent antibody fragment (diabody) in vitro and ovarian cancer xenograft models in vivo. Results EMP2 was found to be highly expressed in over 70% of serous and endometrioid ovarian tumors compared to non-malignant ovarian epithelium using a human ovarian cancer tissue microarray. Using anti-EMP2 diabody, we evaluated the in vitro response of 9 human ovarian cancer cell lines with detectable EMP2 expression. Treatment of human ovarian cancer cell lines with anti-EMP2 diabodies induced cell death and retarded cell growth, and these response rates correlated with cellular EMP2 expression. We next assessed the effects of anti-EMP2 diabodies in mice bearing xenografts from the ovarian endometrioid carcinoma cell line OVCAR5. Anti-EMP2 diabodies significantly suppressed tumor growth and induced cell death in OVCAR5 xenografts. Conclusions These findings indicate that EMP2 is expressed in the majority of ovarian tumors and it may be a feasible target in vivo. PMID:20670949

Clusters of Defects in Semiconductors

DTIC Science & Technology

1984-08-01

onecionbewen-te heica seces .-. o* Fe and.th deec prd *n th *Rlmnecne ae t..* E. STATISTICS The funds from this contract were used to support the research of...characterized at Hughes Research Laboratories. L x No Np N1 . Electron X-ray Sample (cm- 1) (cm- ) (cm-3 ) microprobe Density diffraction .. -. C077 3.6x 10

Spinel from Apollo 12 Olivine Mare Basalts: Chemical Systematics of Selected Major, Minor, and Trace Elements

NASA Technical Reports Server (NTRS)

Papike, J. J.; Karner, J. M.; Shearer, C. K.; Spilde, M. N.

2002-01-01

Spinels from Apollo 12 Olivine basalts have been studied by Electron and Ion microprobe techniques. The zoning trends of major, minor and trace elements provide new insights into the conditions under which planetary basalts form. Additional information is contained in the original extended abstract.

Plasma radome designed for the EMP effects defense

NASA Astrophysics Data System (ADS)

Li, Zhigang; Wang, Jiachun; Cheng, Li; Wang, Qichao

2016-11-01

Radar, as the main detection means, plays an extremely important role in modern warfare. However, it is easily attacked by the electromagnetic pulse (EMP) weapon. In order to defense the threat, a radome formed by plasma is designed. The plasma radome is used to protect the radar systems against EMP coupling through both `front door' and `back door'. What's more, the damage effects of EMP to the radar systems are analyzed, and the protection mechanism of plasma to EMP weapon is discussed. In addition, a simulation experiment is carried out to verify the feasibility of the plasma radome to defense against EMP. The results indicate that the structure performs well, which makes it a new method against EMP weapon.

Role of tumour necrosis factor receptor-1 and nuclear factor-κB in production of TNF-α-induced pro-inflammatory microparticles in endothelial cells.

PubMed

Lee, S K; Yang, S-H; Kwon, I; Lee, O-H; Heo, J H

2014-09-02

Tumour necrosis factor-α (TNF-α) is upregulated in many inflammatory diseases and is also a potent agent for microparticle (MP) generation. Here, we describe an essential role of TNF-α in the production of endothelial cell-derived microparticles (EMPs) in vivo and the function of TNF-α-induced EMPs in endothelial cells. We found that TNF-α rapidly increased blood levels of EMPs in mice. Treatment of human umbilical vein endothelial cells (HUVECs) with TNF-α also induced EMP formation in a time-dependent manner. Silencing of TNF receptor (TNFR)-1 or inhibition of the nuclear factor-κB (NF-κB) in HUVECs impaired the production of TNF-α-induced EMP. Incubation of HUVECs with PKH-67-stained EMPs showed that endothelial cells readily engulfed EMPs, and the engulfed TNF-α-induced EMPs promoted the expression of pro-apoptotic molecules and upregulated intercellular adhesion molecule-1 level on the cell surface, which led to monocyte adhesion. Collectively, our findings indicate that the generation of TNF-α-induced EMPs was mediated by TNFR1 or NF-κB and that EMPs can contribute to apoptosis and inflammation of endothelial cells.

Effect of a brief emergency medicine education course on emergency department work intensity of family physicians.

PubMed

Vaillancourt, Samuel; Schultz, Susan E; Leaver, Chad; Stukel, Thérèse A; Schull, Michael J

2013-01-01

Recently, many Canadian emergency departments (EDs) have struggled with physician staffing shortages. In 2006, the Ontario Ministry of Health and Long-Term Care funded a brief "emergency medicine primer" (EMP) course for family physicians to upgrade or refresh skills, with the goal of increasing their ED work intensity. We sought to determine the effect of the EMP on the ED work intensity of family physicians. A retrospective longitudinal study was conducted of the ED work of 239 family physicians in the 2 years before and after a minimum of 6 months and up to 2 years from completing an EMP course in 2006 to 2008 compared to non-EMP physicians. ED work intensity was defined as the number of ED shifts per month and the number of ED patients seen per month. We conducted two analyses: a before and after comparison of all EMP physicians and a matched cohort analysis matching each EMP physician to four non-EMP physicians on sex, year of medical school graduation, rurality, and pre-EMP ED work intensity. Postcourse, EMP physicians worked 0.5 more ED shifts per month (13% increase, p  =  0.027). Compared to their matched controls, EMP physicians worked 0.7 more shifts per month (13% increase, p  =  0.0032) and saw 15 more patients per month (17% increase, p  =  0.0008) compared to matched non-EMP physicians. The greatest increases were among EMP physicians who were younger, were urban, had previous ED experience, or worked in a high-volume ED. The effect of the EMP course was negligible for physicians with no previous ED experience or working in rural areas. The EMP course is associated with modest increases in ED work intensity among some family physicians, in particular younger physicians in urban areas. No increase was seen among physicians without previous ED experience or working in rural areas.

The effects of electromagnetic pulses (EMP) on the bioactivity of insulin and a preliminary study of mechanism.

PubMed

Chen, Yong Bin; Li, Jing; Qi, Yuhong; Miao, Xia; Zhou, Yongchun; Ren, Dongqing; Guo, G Z

2010-01-01

To investigate the effects of electromagnetic pulse (EMP) exposure on the bioactivity of insulin and a preliminary mechanism for these effects. A tapered parallel plate Gigahertz Transverse Electromagnetic (GTEM) cell with a flared rectangular coaxial transmission line was used to expose the insulin solution to EMP. Concurrent sham-exposed insulin solutions were used as a control. The effect of EMP-exposed insulin on fasting blood glucose levels of type I diabetes model mice, the effect of EMP on binding affinity between insulin and its receptor and the effect of EMP on insulin's fluorescence intensity were detected, respectively. (i) After EMP exposure, compared with sham-exposed insulin, the bioactivity of insulin in decreasing fasting blood glucose levels in type I diabetes model mice was reduced significantly (p = 0.023). (ii) Compared with sham-exposed insulin group, the percentage fluorescein isothiocyannate (FITC) labelling of HL-7702 cells was significantly reduced in the EMP-exposed insulin group (22.7-13.8%, respectively). (iii) Compared with sham-exposed insulin, the fluorescence intensity was significantly reduced in EMP-exposed insulin (p < 0.001). EMP exposure significantly decreased the bioactivity of insulin to reduce the blood glucose levels in type I diabetic mice. This could be due to a decreased binding affinity between insulin and its receptor. This mechanism could involve an alteration of insulin's' conformation caused by EMP exposure.

Increasing the Efficiency of Electron Microprobe Measurements of Minor and Trace Elements in Rutile

NASA Astrophysics Data System (ADS)

Neill, O. K.; Mattinson, C. G.; Donovan, J.; Hernández Uribe, D.; Sains, A.

2016-12-01

Minor and trace element contents of rutile, an accessory mineral found in numerous lithologic settings, has many applications for interpreting earth systems. While these applications vary widely, they share a need for precise and accurate elemental measurements. The electron microprobe can be used to measure rutile compositions, although long X-ray counting times are necessary to achieve acceptable precision. Continuum ("background") intensity can be estimated using the iterative Mean Atomic Number (MAN) method of Donovan and Tingle (1996), obviating the need for direct off-peak background measurements, and reducing counting times by half. For this study, several natural and synthetic rutiles were measured by electron microprobe. Data was collected once but reduced twice, using off-peak and an MAN background corrections, allowing direct comparison of the two methods without influence of other variables (counting time, analyte homogeneity, beam current, calibration standards, etc.). These measurements show that, if a "blank" correction (Donovan et al., 2011, 2016) is used, minor and trace elements of interest can be measured in rutile using the MAN background method in half the time of traditional off-peak measurements, without sacrificing accuracy or precision (Figure 1). This method has already been applied to Zr-in-rutile thermometry of ultra-high pressure metamorphic rocks from the North Qaidam terrane in northwest China. Finally, secondary fluorescence of adjacent phases by continuum X-rays can lead to artificially elevated concentrations. For example, when measuring Zr, care should be taken to avoid analytical spots within 100 microns of zircon or baddeleyite crystals. References: 1) J.J. Donovan and T.N Tingle (1996) J. Microscopy, 2(1), 1-7 2) J.J. Donovan, H.A. Lowers, and B.G. Rusk (2011) Am. Mineral., 96, 274­282 3) J.J. Donovan, J.W. Singer and J.T. Armstrong (2016) Am. Mineral., 101, 1839-1853 4) G.L. Lovizotto et al. (2009) Chem. Geol., 261, 346-369

Development of High Level Electrical Stress Failure Threshold and Prediction Model for Small Scale Junction Integrated Circuits

DTIC Science & Technology

1978-09-01

AWACS EMP Guidelines presents two different models to predict the damage pcwer of the dev-ce and the circuit damage EMP voltage ( VEMP ). Neither of...calculated as K P~ I V BD 6. The damage EMP voltage ( VEMP ) is calculated KZ EMP +IZ =D +BD VBD1F 7. The damage EMP voltage is calculated for collector

Effect of Electromagnetic Pulses (EMP) on associative learning in mice and a preliminary study of mechanism.

PubMed

Chen, Yong Bin; Li, Jing; Liu, Jun Ye; Zeng, Li Hua; Wan, Yi; Li, Yu Rong; Ren, Dongqing; Guo, G Z

2011-12-01

To investigate the effects of electromagnetic pulses (EMP) on associative learning in mice and test a preliminary mechanism for these effects. A tapered parallel plate gigahertz transverse electromagnetic (GTEM) cell with a flared rectangular coaxial transmission line was used to expose male BALB/c mice to EMP (peak-intensity 400 kV/m, rise-time 10 ns, pulse-width 350 ns, 0.5 Hz and total 200 pulses). Concurrent sham-exposed mice were used as a control. Associative learning, oxidative stress in the brain, serum chemistry and the protective action of tocopherol monoglucoside (TMG) in mice were measured, respectively. (1) Twelve hour and 1 day post EMP exposure associative learning was reduced significantly compared with sham control (p<0.05) but recovered at 2 d post EMP exposure. (2) Compared with the sham control, lipid peroxidation of brain tissue and chemiluminescence (CL) intensity increased significantly (p<0.05), while the activity of the antioxidant enzymes Superoxide Dismutase [SOD], Glutathione [GSH], Glutathione Peroxidase [GSH-Px], Catalase [CAT]) decreased significantly (p<0.05) at 3 h, 6 h, 12 h and 1 d post EMP exposure. All these parameters recovered at 2 d post EMP exposure. (3) No significant differences between the sham control group and EMP exposed group were observed in serum cholesterol and triglycerides. (4) Pretreatment of mice with TMG showed protective effects to EMP exposure. EMP exposure significantly decreased associative learning in mice and TMG acted as an effective protective agent from EMP exposure. This mechanism could involve an increase of oxidative stress in brain by EMP exposure.

Effect of Multiple Scattering on the Compton Recoil Current Generated in an EMP, Revisited

DOE PAGES

Farmer, William A.; Friedman, Alex

2015-06-18

Multiple scattering has historically been treated in EMP modeling through the obliquity factor. The validity of this approach is examined here. A simplified model problem, which correctly captures cyclotron motion, Doppler shifting due to the electron motion, and multiple scattering is first considered. The simplified problem is solved three ways: the obliquity factor, Monte-Carlo, and Fokker-Planck finite-difference. Because of the Doppler effect, skewness occurs in the distribution. It is demonstrated that the obliquity factor does not correctly capture this skewness, but the Monte-Carlo and Fokker-Planck finite-difference approaches do. Here, the obliquity factor and Fokker-Planck finite-difference approaches are then compared inmore » a fuller treatment, which includes the initial Klein-Nishina distribution of the electrons, and the momentum dependence of both drag and scattering. It is found that, in general, the obliquity factor is adequate for most situations. However, as the gamma energy increases and the Klein-Nishina becomes more peaked in the forward direction, skewness in the distribution causes greater disagreement between the obliquity factor and a more accurate model of multiple scattering.« less

EMP2 is a novel therapeutic target for endometrial cancer stem cells

PubMed Central

Kiyohara, Meagan H.; Dillard, Christen; Tsui, Jessica; Kim, Sara Ruth; Lu, Jianyi; Sachdev, Divya; Goodglick, Lee; Tong, Maomeng; Torous, Vanda Farahmand; Aryasomayajula, Chinmayi; Wang, Wei; Najafzadeh, Parisa; Gordon, Lynn K.; Braun, Jonathan; McDermott, Sean; Wicha, Max S.; Wadehra, Madhuri

2017-01-01

Previous studies have suggested that overexpression of the oncogenic protein epithelial membrane protein-2 (EMP2) correlates with endometrial carcinoma progression and ultimately poor survival from disease. To understand the role of EMP2 in the etiology of disease, gene analysis was performed to show transcripts that are reciprocally regulated by EMP2 levels. In particular, EMP2 expression correlates with and helps regulate the expression of several cancer stem cell associated markers including aldehyde dehydrogenase 1 (ALDH1). ALDH expression significantly promotes tumor initiation and correlates with the levels of EMP2 expression in both patient samples and tumor cell lines. As therapy against CSCs in endometrial cancer is lacking, the ability of anti-EMP2 IgG1 therapy to reduce primary and secondary tumor formation using xenograft HEC1A models was determined. Anti-EMP2 IgG1 reduced the expression and activity of ALDH and correspondingly reduced both primary and secondary tumor load. Our results collectively suggest that anti-EMP2 therapy may be a novel method of reducing endometrial cancer stem cells. PMID:28604744

Auger electron spectroscopy at high spatial resolution and nA primary beam currents

NASA Technical Reports Server (NTRS)

Todd, G.; Poppa, H.; Moorhead, D.; Bales, M.

1975-01-01

An experimental Auger microprobe system is described which incorporates a field-emission electron gun and total beam currents in the nanoampere range. The distinguishing characteristics of this system include a large multistation UHV specimen chamber, pulse counting and fully digital Auger signal-processing techniques, and digital referencing methods to eliminate the effects of beam instabilities. Some preliminary results obtained with this system are described, and it is concluded that field-emission electron sources can be used for high-resolution Auger electron spectroscopy with primary-beam spots of less than 100 nm and beam currents of the order of 1 nA.

Microstructural study of the nickel-base alloy WAZ-20 using qualitative and quantitative electron optical techniques

NASA Technical Reports Server (NTRS)

Young, S. G.

1973-01-01

The NASA nickel-base alloy WAZ-20 was analyzed by advanced metallographic techniques to qualitatively and quantitatively characterize its phases and stability. The as-cast alloy contained primary gamma-prime, a coarse gamma-gamma prime eutectic, a gamma-fine gamma prime matrix, and MC carbides. A specimen aged at 870 C for 1000 hours contained these same constituents and a few widely scattered high W particles. No detrimental phases (such as sigma or mu) were observed. Scanning electron microscope, light metallography, and replica electron microscope methods are compared. The value of quantitative electron microprobe techniques such as spot and area analysis is demonstrated.

Interfacial Fracture Toughness of Adhesive Resin Cement-Lithium-Disilicate/Resin-Composite Blocks.

PubMed

Mesmar, Samer; Ruse, N Dorin

2017-09-15

Resin composite blocks (RCB) are advocated as alternative to ceramic blocks (CB). Prior to use, adherence to these materials should characterized. This study aimed to test the null hypothesis (H 0 ) that material and surface treatment combinations do not influence interfacial fracture toughness (K IC ) of a self-cured adhesive resin cement [RelyX Ultimate (RXU)] to RCB or CB, under nonaged and aged conditions. Two RCB, Lava Ultimate (LU) and Enamic (EN), and one CB, IPS e.max Press (EMP) were used. Half-size [(6 × 6 × 6 × 6 mm)] specimens were prepared for EMP (n = 30), EN (n = 30), and LU (n = 60). RCB specimens were prepared by wet cutting/grinding, while CB specimens were pressed. Surfaces of EMP and EN were preconditioned with hydrofluoric acid (5%); surfaces of LU were sandblasted with either 27 μm alumina (LUS) or 30 μm silica-modified alumina Rocatec soft (LUR). All specimens were bonded with Scotchbond Universal adhesive and RXU. Additionally, twenty (4 × 4 × 4 × 8 mm) RXU specimens were prepared. All specimens were stored in water at 37°C and tested after 1 and 60 days. Interfacial K IC was determined with the notchless triangular prism specimen K IC test. Results were analyzed with two-way ANOVA and Scheffé multiple means comparisons (α = 0.05). Preconditioned and selected fractured surfaces were characterized with scanning electron microscopy. At 24 hours, LUS-RXU and LUR-RXU had significantly higher interfacial K IC than EN-RXU and EMP-RXU and were not different from K IC of RXU. Aging lead to a significant decrease in K IC of RXU and interfacial K IC of LUS-RXU, LUR-RXU, and EMP-RXU; interfacial K IC of EN-RXU was not affected. Based on the results, H 0 was rejected. Under the conditions of this study, at 24 hours, interfacial K IC of LUS-RXU and LUR-RXU was superior to EMP-RXU and EN-RXU. Aging in water at 37°C did not affect interfacial K IC of EN-RXU but adversely affected K IC of RXU and the other interfacial K IC . The results suggest that RXU and its adherence to LU and EMP deteriorates upon exposure to water at 37°C. In making clinical decisions related to material selection, practitioners should consider in vitro results. © 2017 by the American College of Prosthodontists.

The Structure and Properties of Diffusion Assisted Bonded Joints in 17-4 PH, Type 347, 15-5 PH and Nitronic 40 Stainless Steels

NASA Technical Reports Server (NTRS)

Wigley, D. A.

1981-01-01

Diffusion assisted bonds are formed in 17-4 PH, 15-5 PH, type 347 and Nitronic 40 stainless steels using electrodeposited copper as the bonding agent. The bonds are analyzed by conventional metallographic, electron microprobe analysis, and scanning electron microscopic techniques as well as Charpy V-notch impact tests at temperatures of 77 and 300 K. Results are discussed in terms of a postulated model for the bonding process.

Influence of irradiation on release of endothelial microparticles (EMP) in vitro.

PubMed

Neuber, Christin; Pufe, Johanna; Pietzsch, Jens

2015-01-01

Survivors of Hodgkin's disease as well as of breast and lung cancer are at risk of radiation-associated cardiovascular disease. Recent studies demonstrated a correlation between cardiovascular risk factors and circulating endothelial microparticles (EMP) and thereby suggest increased EMP levels in circulation to be an early biomarker of endothelial dysfunction and cardiovascular risk. This prompted us to analyze the amount of EMP released by human aortic endothelial cells (HAEC) after exposure to different doses of X-ray (0.4, 2, 4, 6, and 20 Gy) using antibodies against the endothelial cell markers CD31, CD144, and CD146 by flow cytometry. In this pilot experiment only CD146 proved appropriate for quantification of HAEC-derived EMP. Exposure of HAEC to different doses of X-ray did not significantly influence formation of CD146-positive EMP. However, low doses (0.4 Gy) tended to decrease EMP formation, whereas higher doses (2 or 4 Gy) slightly increased release of CD146-positive EMP. By contrast, inflammatory activation of HAEC by TPA significantly increased EMP release about 15-fold (P <  0.01). In conclusion, under the present experimental conditions EMP did not prove a suitable biomarker for radiation-induced endothelial dysfunction in vitro.

The new confocal heavy ion microprobe beamline at ANSTO: The first microprobe resolution tests and applications for elemental imaging and analysis

NASA Astrophysics Data System (ADS)

Pastuovic, Z.; Siegele, R.; Cohen, D. D.; Mann, M.; Ionescu, M.; Button, D.; Long, S.

2017-08-01

The Centre for Accelerator Science facility at ANSTO has been expanded with the new NEC 6 MV ;SIRIUS; accelerator system in 2015. In this paper we present a detailed description of the new nuclear microprobe-Confocal Heavy Ion Micro-Probe (CHIMP) together with results of the microprobe resolution testing and the elemental analysis performed on typical samples of mineral ore deposits and hyper-accumulating plants regularly measured at ANSTO. The CHIMP focusing and scanning systems are based on the OM-150 Oxford quadrupole triplet and the OM-26 separated scan-coil doublet configurations. A maximum ion rigidity of 38.9 amu-MeV was determined for the following nuclear microprobe configuration: the distance from object aperture to collimating slits of 5890 mm, the working distance of 165 mm and the lens bore diameter of 11 mm. The overall distance from the object to the image plane is 7138 mm. The CHIMP beamline has been tested with the 3 MeV H+ and 6 MeV He2+ ion beams. The settings of the object and collimating apertures have been optimized using the WinTRAX simulation code for calculation of the optimum acceptance settings in order to obtain the highest possible ion current for beam spot sizes of 1 μm and 5 μm. For optimized aperture settings of the CHIMP the beam brightness was measured to be ∼0.9 pA μm-2 mrad-2 for 3 MeV H+ ions, while the brightness of ∼0.4 pA μm-2 mrad-2 was measured for 6 MeV He2+ ions. The smallest beam sizes were achieved using a microbeam with reduced particle rate of 1000 Hz passing through the object slit apertures several micrometers wide. Under these conditions a spatial resolution of ∼0.6 μm × 1.5 μm for 3 MeV H+ and ∼1.8 μm × 1.8 μm for 6 MeV He2+ microbeams in horizontal (and vertical) dimension has been achieved. The beam sizes were verified using STIM imaging on 2000 and 1000 mesh Cu electron microscope grids.

Classification of six ordinary chondrites from Texas

NASA Astrophysics Data System (ADS)

Ehlmann, Arthur J.; Keil, Klaus

1988-12-01

Based on optical microscopy, modal and electron microprobe analyses, six ordinary chondrites from Texas were classified in compositional groups, petrologic types, and shock facies. These meteorites are Comanche (stone), L5c; Haskell, L5c; Deport (a), H4b; Naruna (a), H4b; Naruna (b), H4b; and Clarendon (b), H5d.

Magnetic particles extracted from manganese nodules: Suggested origin from stony and iron meteorites

USGS Publications Warehouse

Finkelman, R.B.

1970-01-01

On the basis of x-ray diffraction and electron microprobe data, spherical and ellipsoidal particles extracted from manganese nodules were divided into three groups. Group I particles are believed to be derived from iron meteorites, and Group II particles from stony meteorites. Group III particles are believed to be volcanic in origin.

Measurement of carbon distribution in nuclear fuel pin cladding specimens by means of a secondary ion mass spectrometer

NASA Astrophysics Data System (ADS)

Bart, Gerhard; Aerne, Ernst Tino; Burri, Martin; Zwicky, Hans-Urs

1986-11-01

Cladding carburization during irradiation of advanced mixed uranium plutonium carbide fast breeder reactor fuel is possibly a life limiting fuel pin factor. The quantitative assessment of such clad carbon embrittlement is difficult to perform by electron microprobe analysis because of sample surface contamination, and due to the very low energy of the carbon K α X-ray transition. The work presented here describes a method developed at the Swiss Federal Institute for Reactor Research (EIR) to use shielded secondary ion mass spectrometry (SIMS) as an accurate tool to determine radial distribution profiles of carbon in radioactive stainless steel fuel pin cladding. Compared with nuclear microprobe analysis (NMA) [1], which is also an accurate method for carbon analysis, the SIMS method distinguishes itself by its versatility for simultaneous determination of additional impurities.

Clinical CVVH model removes endothelium-derived microparticles from circulation

PubMed Central

Abdelhafeez, Abdelhafeez H.; Jeziorczak, Paul M.; Schaid, Terry R.; Hoefs, Susan L.; Kaul, Sushma; Nanchal, Rahul; Jacobs, Elizabeth R.; Densmore, John C.

2014-01-01

Background Endothelium-derived microparticles (EMPs) are submicron vesicles released from the plasma membrane of endothelial cells in response to injury, apoptosis or activation. We have previously demonstrated EMP-induced acute lung injury (ALI) in animal models and endothelial barrier dysfunction in vitro. Current treatment options for ALI are limited and consist of supportive therapies. We hypothesize that standard clinical continuous venovenous hemofiltration (CVVH) reduces serum EMP levels and may be adapted as a potential therapeutic intervention. Materials and methods EMPs were generated from plasminogen activation inhibitor-1 (PAI-1)-stimulated human umbilical vein endothelial cells (HUVECs). Flow cytometric analysis was used to characterize EMPs as CD31- and annexin V-positive events in a submicron size gate. Enumeration was completed against a known concentration of latex beads. Ultimately, a concentration of ~650,000 EMP/mL perfusate fluid (total 470 mL) was circulated through a standard CVVH filter (pore size 200 μm, flow rate 250 mL/hr) for a period of 70 minutes. 0.5 mL aliquots were removed at 5- to 10-minute intervals for flow cytometric analysis. EMP concentration in the dialysate was measured at the end of 4 hours to better understand the fate of EMPs. Results A progressive decrease in circulating EMP concentration was noted using standard CVVH at 250 mL/hr (a clinical standard rate) from a 470 mL volume modelling a patient's circulation. A 50% reduction was noted within the first 30 minutes. EMPs entering the dialysate after 4 hours were 5.7% of the EMP original concentration. Conclusion These data demonstrate that standard CVVH can remove EMPs from circulation in a circuit modelling a patient. An animal model of hemofiltration with induction of EMP release is required to test the therapeutic potential of this finding and potential of application in early treatment of ALI. PMID:24596654

[Effect of EMP-1 gene on human esophageal cancer cell line].

PubMed

Wang, Hai-tao; Liu, Zhi-hua; Wang, Xiu-qin; Wu, Min

2002-03-01

EMP-1 was selected from a series of differential expressed genes obtained from cDNA microarray in the authors' lab. Epithelial membrane pnteiu-1 gene (EMP-1) was expressed 6 fold lower in esophageal cancer than in normal tissue. The authors further designed the experiment to study the effect of human EMP-1 gene on human esophageal cancer cell line in order to explain the function of this gene on the carcinogensis and progression esophageal cancer. EMP-1 gene was cloned into eukaryotic vector and transfected into the human esophageal cancer cell line. The transfection effect was qualified by Western blot and RT-PCR method. The cell growth curve was observed and the cell cycle was checked by FACS method. EMP-1 was transfected into EC9706 cell line and its expression was up-regulated. The cell growth is accelerated and expression of EMP-1 is linked to induction of S phase arrest. EMP-1 gene has some relationship with carcinogenesis of esophagus.

Low flux laboratory test of the Internal Discharge Monitor (IDM) experiment intended for CRRES. [Combined Release and Rediation Effects Satellite

NASA Technical Reports Server (NTRS)

Coakley, P. G.; Treadaway, M. J.; Robinson, P. A., Jr.

1985-01-01

Twelve planar printed circuit board samples and four cable samples were exposed to a distributed electron source of 150 keV to 2.5 MeV at 4.5 pA/sq cm and were monitored for electron-caused EMP. Discharges were recorded on 10 of the 16 samples during the first 18 hours of testing (total incident fluence equaled 1.8 x 10 to the 12th e/sq cm).

Epithelial Membrane Protein-2 Expression is an Early Predictor of Endometrial Cancer Development

PubMed Central

Habeeb, Omar; Goodglick, Lee; Soslow, Robert A.; Rao, Rajiv; Gordon, Lynn K.; Schirripa, Osvaldo; Horvath, Steve; Braun, Jonathan; Seligson, David B.; Wadehra, Madhuri

2010-01-01

BACKGROUND Endometrial cancer (EC) is a common malignancy worldwide. It is often preceded by endometrial hyperplasia, whose management and risk of neoplastic progression vary. Previously, we have shown that the tetraspan protein Epithelial Membrane Protein-2 (EMP2) is a prognostic indicator for EC aggressiveness and survival. Here we validate the expression of EMP2 in EC, and further examine whether EMP2 expression within preneoplastic lesions is an early prognostic biomarker for EC development. METHODS A tissue microarray (TMA) was constructed with a wide representation of benign and malignant endometrial samples. The TMA contains a metachronous cohort of cases from individuals who either developed or did not develop EC. Intensity and frequency of EMP2 expression were assessed using immunohistochemistry. RESULTS There was a stepwise, statistically-significant increase in the average EMP2 expression from benign to hyperplasia to atypia to EC. Furthermore, detailed analysis of EMP2 expression in potentially premalignant cases demonstrated that EMP2 positivity was a strong predictor for EC development. CONCLUSION EMP2 is an early predictor of EC development in preneoplastic lesions. In addition, combined with our previous findings, these results validate that EMP2 as a novel biomarker for EC development. PMID:20578181

Electromagnetic pulse (EMP) coupling codes for use with the vulnerability/lethality (VIL) taxonomy. Final report, June-October 1984

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

Mar, M.H.

1995-07-01

Based on the vulnerability Lethality (V/L) taxonomy developed by the Ballistic Vulnerability Lethality Division (BVLD) of the Survivability Lethality Analysis Directorate (SLAD), a nuclear electromagnetic pulse (EMP) coupling V/L analysis taxonomy has been developed. A nuclear EMP threat to a military system can be divided into two levels: (1) coupling to a system level through a cable, antenna, or aperture; and (2) the component level. This report will focus on the initial condition, which includes threat definition and target description, as well as the mapping process from the initial condition to damaged components state. EMP coupling analysis at a systemmore » level is used to accomplish this. This report introduces the nature of EMP threat, interaction between the threat and target, and how the output of EMP coupling analysis at a system level becomes the input to the component level analysis. Many different tools (EMP coupling codes) will be discussed for the mapping process, which correponds to the physics of phenomenology. This EMP coupling V/L taxonomy and the models identified in this report will provide the tools necessary to conduct basic V/L analysis of EMP coupling.« less

Necessity of re-evaluation of estramustine phosphate sodium (EMP) as a treatment option for first-line monotherapy in advanced prostate cancer.

PubMed

Kitamura, T

2001-02-01

Estramustine phosphate sodium (EMP) was first introduced in the early 1970s for the treatment of prostate cancer, when EMP was supposed to have the dual effect of estrogenic activity and cytotoxicity. For the following decades, it was used mainly in hormone-refractory cases, with a conventional dosage of 4-9 capsules/day, which showed a 30-35% objective response rate. However, a very limited number of cases have been reported that used EMP as a first-line monotherapy in the conventional dosage. One study showed a response rate of 82%, which is at least as effective as conventional estrogen (diethylstilbestrol; DES) monotherapy. Nevertheless, EMP was almost abandoned for the treatment of prostate cancer because of severe adverse side-effects, especially in the cardiovascular system and gastrointestinal tract. Recently, two facts have become evident. First, EMP interferes with cellular microtubule dynamics but does not show alkylating effects. Second, EMP is able to produce a complex with calcium when dairy products are taken concomitantly with EMP, resulting in a decrease in the absorption rate of EMP from the gut. Many clinical trials have been undertaken without warning against concomitant dairy product intake since the introduction of EMP. This fact will jeopardize almost all the clinical trials performed before 1990. It is considered that response rates have been underestimated and better results could have been obtained because side-effects decrease dose-dependently. Low-dose EMP monotherapy (2 capsules/day) has been performed infrequently in previously untreated advanced prostate cancer. The only large trial by the European Organization for Research and Treatment of Cancer in 1984 was biased in selecting patients. Nevertheless, the response rate of EMP is comparable to that of DES. In this study, the adverse side-effects of EMP were less than that of DES. Recently, a study was conducted at the University of Tokyo of 11 patients with advanced prostate cancer on low-dose EMP as first-line monotherapy. The study found that the mean serum prostate-specific antigen level decreased to within the normal range by day 50; mean serum testosterone, leutinizing hormone and follicle-stimulating hormone reduced to undetectable levels by day 20; and mean serum estradiol increased to a very high level within 1 week. These data implicate that low-dose EMP can suppress quickly and adequately the pituitary-gonadal axis, although the antitumor effect has not as yet been elucidated. For these reasons, it is necessary to re-evaluate low-dose EMP monotherapy in previously untreated advanced prostate cancer.

Phase transformations in 40-60-GPa shocked gneisses from the Haughton Crater (Canada): An Analytical Transmission Electron Microscopy (ATEM) study

NASA Technical Reports Server (NTRS)

Martinez, I.; Guyot, F.; Schaerer, U.

1992-01-01

In order to better understand phase transformations, chemical migration, and isotopic disequilibrium in highly shocked rocks, we have performed a microprobe and an ATEM study on gneisses shocked up to 60 GPa from the Haughton Crater. This study reveals the following chemical and structural characteristics: (1) SiO2 dominant areas are formed by a mixture of pure SiO2 polycrystalline quartz identified by electron diffraction pattern and chemical analysis and a silica-rich amorphous phase containing minor amounts of aluminium, potassium, and iron; (2) Areas with biotitelike composition are formed by less than 200-nm grains of iron-rich spinels embedded in a silica-rich amorphous phase that is very similar to the one described above; (3) Layers with feldsparlike composition are constituted by 100-200-nm-sized alumina-rich grains (the indexation of the crystalline structure is under progress) and the silica-rich amorphous phase; (4) Zones characterized by the unusual Al/Si ratio close to 1 are formed by spinel grains (200-nm-sized) embedded in the same silica-rich amorphous phase; and (5) The fracturated sillimanites contain domains with a lamellar structure, defined by the intercalation of 100-nm-wide lamellae of mullite crystals and of a silica-rich amorphous phase. These mullite crystals preserved the crystallographical orientation of the preshock sillimanite. All compositional domains, identified at the microprobe scale, can thus be explained by a mixture in different proportion between the following phases: (1) a silica-rich amorphous phase, with minor Al and K; (2) quartz crystals; (3) spinel crystals and alumina-rich crystals; (4) sillimanite; and (5) mullite. Such mixtures of amorphous phases and crystals in different proportions explain disturbed isotope systems in these rocks and chemical heterogeneities observed on the microprobe.

Functional group and individual maceral chemistry of high volatile bituminous coals from southern Indiana: Controls on coking

USGS Publications Warehouse

Walker, R.; Mastalerz, Maria

2004-01-01

The individual maceral chemistries of two Pennsylvanian, high volatile bituminous coals, the Danville Coal Member (Dugger Formation, R o=0.55%) and the Lower Block Coal Member (Brazil Formation, R o=0.56%) of Indiana, were investigated using electron microprobe and Fourier Transform Infrared Spectrometry (FTIR) techniques, with the purpose of understanding differences in their coking behavior. Microprobe results reveal that carbon contents are highest in inertinite and sporinite, followed by desmocollinite and telocollinite. Oxygen and organic nitrogen are most abundant in telocollinite and desmocollinite; sporinite and inertinite contain lesser amounts of these two elements. Organic sulfur contents are highest in sporinite, lowest in inertinite, and intermediate in desmocollinite and telocollinite. Vitrinites within the Danville and Lower Block coals are very similar in elemental composition, while Lower Block inertinites and sporinites have higher carbon, lower oxygen, and sulfur contents which, when combined with the inertinite-and sporinite-rich composition of the Lower Block seam, strongly influences its whole coal chemistry. Fourier transform infrared spectrometry revealed greater aromatic hydrogen in the Lower Block coal, along with higher CH2/CH3 ratios, which suggest that liptinites contribute considerable amounts of long-chain, unbranched aliphatics to the overall kerogen composition of the Lower Block coal. Long-chain, unbranched aliphatics crack at higher temperatures, producing tar and oily byproducts during coking; these may help increase Lower Block plasticity. Electron microprobe and FTIR results indicate that individual maceral chemistries, combined with the maceral composition of the seam, are the primary control of better coking properties of the Lower Block coal. ?? 2003 Elsevier B.V. All rights reserved.

Endothelial cell-derived microparticles loaded with iron oxide nanoparticles: feasibility of MR imaging monitoring in mice.

PubMed

Al Faraj, Achraf; Gazeau, Florence; Wilhelm, Claire; Devue, Cécile; Guérin, Coralie L; Péchoux, Christine; Paradis, Valérie; Clément, Olivier; Boulanger, Chantal M; Rautou, Pierre-Emmanuel

2012-04-01

To assess the feasibility of loading iron oxide nanoparticles in endothelial microparticles (EMPs), thereby enabling their noninvasive monitoring with magnetic resonance (MR) imaging in mice. Experiments were approved by the French Ministry of Agriculture. Endothelial cells, first labeled with anionic superparamagnetic nanoparticles, were stimulated to generate EMPs, carrying the nanoparticles in their inner compartment. C57BL/6 mice received an intravenous injection of nanoparticle-loaded EMPs, free nanoparticles, or the supernatant of nanoparticle-loaded EMPs. A 1-week follow-up was performed with a 4.7-T MR imaging device by using a gradient-echo sequence for imaging spleen, liver, and kidney and a radial very-short-echo time sequence for lung imaging. Comparisons were performed by using the Student t test. The signal intensity loss induced by nanoparticle-loaded EMPs or free nanoparticles was readily detected within 5 minutes after injection in the liver and spleen, with a more pronounced effect in the spleen for the magnetic EMPs. The kinetics of signal intensity attenuation differed for nanoparticle-loaded EMPs and free nanoparticles. No signal intensity changes were observed in mice injected with the supernatant of nanoparticle-loaded EMPs, confirming that cells had not released free nanoparticles, but only in association with EMPs. The results were confirmed by using Perls staining and immunofluorescence analysis. The strategy to generate EMPs with magnetic properties allowed noninvasive MR imaging assessment and follow-up of EMPs and opens perspectives for imaging the implications of these cellular vectors in diseases. © RSNA, 2012.

Modal Mineralogy of Lunar Soils

NASA Astrophysics Data System (ADS)

Taylor, J.; Martel, L.; Lucey, P. G.; Crites, S. T.; Blake, D. F.

2012-12-01

Modal mineralogy of the lunar regolith is fundamentally important. It varies with the composition of underlying bedrock, extent of addition of materials excavated by impact both local and distant, and small-scale reworking by micrometeorite bombardment, so it contains information about local geological history. Determining modal mineralogy of soils provides vital ground truth to remote sensing studies. Mineralogy can be determined by a variety of techniques that provide complementary information: X-Ray Diffraction (XRD), optical point counting, element mapping by scanning electron microscopy (SEM) or electron microprobe (EMP), and normative calculation from a bulk chemical analysis. SEM and EMP element mapping can be converted into mineral modal abundances in a variety of ways, including defining compositional windows for specific minerals and using image processing techniques. XRD provides direct determination of the phases present, but gives little information about the chemical composition of those phases. We have launched a project to determine the modal mineralogy of over 100 lunar soils from all Apollo sites. The goal is to use this quantitative mineralogy and laboratory and remote reflectance spectra of the same soils to improve our ability to extract quantitative mineralogy from remote sensing data. Samples (< 1mm bulk soils) were dry-sieved and the <150 micron fractions analyzed in a Terra XRD instrument (InXitu, Inc.) using sample sizes of ~35 mg. We reduced the data using Reitveld refinement as implemented by the Jade program (Materials Data, Inc.). Glass abundances were determined by choosing a linear background and fitting a broad Gaussian to the scattering hump above background. Quantitative XRD is well established, but usually requires some calibration, in spite of the sophisticated Reitveld refinement and whole-pattern fitting. We calibrated the instrument by using mixtures of terrestrial minerals and results from the Lunar Sample Characterization Consortium (data available at web.utk.edu/~pgi/data.html). Without calibration our results differ (though by < 10 % relative) from those of the LSCC. Discrepancies may stem from the uncertainties in assigning a pixel to a specific mineral in the SEM point counting approach, not completely randomized orientations of the mineral grains during analysis by Terra, or shock effects in minerals not being taken into account by the Reitveld method. Data for 30 soils from the Apollo 16 site show that on a glass-free basis plagioclase ranges from 78 to 94 wt%, with the sites on the Descartes Mountains (Stations 4, 11, and 13) tending to contain more plagioclase, consistent with previous conclusions that the Descartes highlands are more feldspathic than the Cayley Plains. The relative abundance among mafic silicates varies throughout the site, although the small abundance of the mafic components leads to uncertainty in the Reitveld analysis. Particularly interesting for using the combination of remote sensing and sample measurements is the observation that modal plagioclase is systematically greater than normative plagioclase (normative/modal plagioclase is 0.83 to 0.95). A difference between modes and norms is not unusual, but this substantial difference indicates that the glass in the Apollo 16 regolith is more mafic than the crystalline material, consistent with the average composition of impact glass in Apollo 16 samples compared to bulk soils.

Plasmodium falciparum erythrocyte membrane protein-1 specifically suppresses early production of host interferon-gamma.

PubMed

D'Ombrain, Marthe C; Voss, Till S; Maier, Alexander G; Pearce, J Andrew; Hansen, Diana S; Cowman, Alan F; Schofield, Louis

2007-08-16

Plasmodium falciparum erythrocyte membrane protein-1 (PfEMP-1) is a variable antigen expressed by P. falciparum, the malarial parasite. PfEMP-1, present on the surface of infected host erythrocytes, mediates erythrocyte binding to vascular endothelium, enabling the parasite to avoid splenic clearance. In addition, PfEMP-1 is proposed to regulate host immune responses via interactions with the CD36 receptor on antigen-presenting cells. We investigated the immunoregulatory function of PfEMP-1 by comparing host cell responses to erythrocytes infected with either wild-type parasites or transgenic parasites lacking PfEMP-1. We showed that PfEMP-1 suppresses the production of the cytokine interferon-gamma by human peripheral blood mononuclear cells early after exposure to P. falciparum. Suppression of this rapid proinflammatory response was CD36 independent and specific to interferon-gamma production by gammadelta-T, NK, and alphabeta-T cells. These data demonstrate a parasite strategy for downregulating the proinflammatory interferon-gamma response and further establish transgenic parasites lacking PfEMP-1 as powerful tools for elucidating PfEMP-1 functions.

Evaluation of erythroblast macrophage protein related to erythroblastic islands in patients with hematopoietic stem cell transplantation

PubMed Central

2013-01-01

Background Hematopoietic evaluation of the patients after Hematopoietic stem cell transplantation (HSCT) is very important. Erythroblast macrophage protein (Emp) is a key protein with function in normal differentiation of erythroid cells and macrophages. Emp expression correlates with erythroblastic island formation, a process widely believed to be associated with hematopoiesis in bone marrow. We aimed to investigate the hematopoietic function of bone marrow from 46 HSCT patients and 16 inpatients with severe anemia applied to the treatment of EPO by measuring Emp expression level. Methods Emp mRNA and protein expression levels in mononuclear cells of bone marrow and peripheral blood samples were detected by RT-PCR and Western blotting method respectively. Results While hematopoiesis occurs in bone marrow, Emp expression level was elevated and more erythroblastic islands were found , and Emp is upregulated in bone marrow in response to erythropoietin (EPO) treatment. Conclusions Emp expression correlates with erythroblastic island formation and has an important function for bone marrow hematopoiesis. Emp could be a potential biomarker for hematopoietic evaluation of HSCT patients. PMID:23566571

EMP-1 promotes tumorigenesis of NSCLC through PI3K/AKT pathway.

PubMed

Lai, Senyan; Wang, Guihua; Cao, Xiaonian; Li, Zhaoming; Hu, Junbo; Wang, Jing

2012-12-01

This study examined the role of EMP-1 in tumorigenesis of non-small cell lung carcinoma (NSCLC) and the possible mechanism. Specimens were collected from 28 patients with benign lung diseases and 28 with NSCLC, and immunohistochemically detected to evaluate the correlation of EMP-1 expression to the clinical features of NSCLC. Recombinant adenovirus was constructed to over-express EMP-1 and then infect PC9 cells. Cell proliferation was measured by Ki67 staining. Western blotting was performed to examine the effect of EMP-1 on the PI3K/AKT signaling. Moreover, tumor xenografts were established by subcutaneous injection of PC9 cell suspension (about 5×10(7)/mL in 100 μL of PBS) into the right hind limbs of athymic nude mice. The results showed EMP-1 was significantly up-regulated in NSCLC patients as compared with those with benign lung diseases. Over-expression of EMP-1 promoted proliferation of PC9 cells, which coincided with the activation of the PI3K/AKT pathway. EMP-1 promoted the growth of xenografts of PC9 cells in athymic nude mice. It was concluded that EMP-1 expression may contribute to the development and progress of NSCLC by activating PI3K/AKT pathway.

[Clinical analysis on extramedullary plasmacytoma in the upper airway].

PubMed

Ge, Shenglei; Tan, Zhiqiang; Xie, Dinghua; Yi, Yan

2013-03-01

To investigate the clinical manifestation, treatment and prognosis of extramedullary plasmacytoma(EMP) in the upper airway, and to improve the diagnosis and outcome of EMP treatment. Clinical data of 26 EMP cases were reviewed retrospectively, and then compared with multiple myeloma(MM) patients presenting with lesions in upper airway. Of 26 cases, 9 cases with the tumors occurred in nasal cavities, 7 in nasal sinuses, 6 in pharyngeal, 4 in throat, mainly manifesting with local masses and relevant symptoms. The manifestations of clinical, endoscopy findings and pathologic results in EMP patients were not distinguishable from the lesions of MM patients, while MM patients often accompanied by other findings, such as anemia and bone damage. Involvement of neck lymph nodes was more common in MM patients than in EMP patients. Ten patients were treated with surgery, and 16 patients with surgery and radiotherapy. Of the seven EMP patients with involvement of neck lymph nodes, four patients received additional chemotherapy besides surgery and radiotherapy, and no local relapse and MM happened in them, while of the three patients only received surgery and radiotherapy, one local relapse were found and one progressed to MM. The diagnosis of EMPs mainly depends on pathological results. The judgment of pathologists and application of molecular biology technology are vital for the diagnosis of EMP in upper airway, and MM must be excluded very carefully in the diagnosis of EMP. Surgery combined with radiotherapy is the main treatment for EMP in the upper airway, and the prognosis is good but the follow-up should be taken. Besides surgery and radiotherapy, chemotherapy is beneficial for the EMP patients accompanied with lesions in neck lymph nodes.

A comparative assessment of adverse event classification in the out-of-hospital setting.

PubMed

Patterson, P Daniel; Lave, Judith R; Weaver, Matthew D; Guyette, Francis X; Arnold, Robert M; Martin-Gill, Christian; Rittenberger, Jon C; Krackhardt, David; Mosesso, Vincent N; Roth, Ronald N; Wadas, Richard J; Yealy, Donald M

2014-01-01

We sought to test reliability of two approaches to classify adverse events (AEs) associated with helicopter EMS (HEMS) transport. The first approach for AE classification involved flight nurses and paramedics (RN/Medics) and mid-career emergency physicians (MC-EMPs) independently reviewing 50 randomly selected HEMS medical records. The second approach involved RN/Medics and MC-EMPs meeting as a group to openly discuss 20 additional medical records and reach consensus-based AE decision. We compared all AE decisions to a reference criterion based on the decision of three senior emergency physicians (Sr-EMPs). We designed a study to detect an improvement in agreement (reliability) from fair (kappa = 0.2) to moderate (kappa = 0.5). We calculated sensitivity, specificity, percent agreement, and positive and negative predictive values (PPV/NPV). For the independent reviews, the Sr-EMP group identified 26 AEs while individual clinician reviewers identified between 19 and 50 AEs. Agreement on the presence/absence of an AE between Sr-EMPs and three MC-EMPs ranged from κ = 0.20 to κ = 0.25. Agreement between Sr-EMPs and three RN/Medics ranged from κ = 0.11 to κ = 0.19. For the consensus/open-discussion approach, the Sr-EMPs identified 13 AEs, the MC-EMP group identified 18 AEs, and RN/medic group identified 36 AEs. Agreement between Sr-EMPs and MC-EMP group was (κ = 0.30 95%CI -0.12, 0.72), whereas agreement between Sr-EMPs and RN/medic group was (κ = 0.40 95%CI 0.01, 0.79). Agreement between all three groups was fair (κ = 0.33, 95%CI 0.06, 0.66). Percent agreement (58-68%) and NPV (63-76%) was moderately dissimilar between clinicians, while sensitivity (25-80%), specificity (43-97%), and PPV (48-83%) varied. We identified a higher level of agreement/reliability in AE decisions utilizing a consensus-based approach for review rather than independent reviews.

A retrospective study of correlation of morphologic patterns, MIB1 proliferation index, and survival analysis in 134 cases of plasmacytoma.

PubMed

Ghodke, Kiran; Shet, Tanuja; Epari, Sridhar; Sengar, Manju; Menon, Hari; Gujral, Sumeet

2015-06-01

Plasmacytoma classified into solitary plasmacytoma of bone (SPB) and extramedullary plasmacytoma (EMP) is characterized by infiltrate of plasma cells of diverse maturity and by their monoclonal immunoglobulin products. Both SPB and EMP represent different groups of neoplasm in terms of location, tumor progression, and overall survival rate. There is a need for features that indicate likelihood of myeloma in patients with plasmacytoma without other manifestations. This study was an attempt to study the morphologic patterns of plasmacytoma (SPB and EMP), MIB1 proliferation index, and correlation of these with clinicopathologic features and survival of the patients. The study group comprised of 134 cases of plasmacytoma (88 SPB and 46 EMP) over duration of 8 years and were graded as per Bartl's histologic grading system. Commonest site was vertebral body in SPB (36%) and upper aerodigestive tract in EMP (48%). On serum electrophoresis, overall M band was detected in 41% cases. Both SPB and EMP on histology revealed similar morphologic features. MIB1 proliferation index ranged from less than 1% to 80%. It was slightly higher in EMP in comparison with SPB (P value = .002). Seventy percent of cases, which progressed to multiple myeloma (MM) showed MIB1 labeling index more than 10%; however, it was not statistically significant in predicting the disease progression. With the median follow-up of 19 months (range, 1-99 months), 10 SPB had disease progression of which 7 converted to MM, and 3 developed EMP, with a median interval of 21 months (range, 8-75 months) for the development of MM and 3 months (range, 3-9 months) for the progression to EMP. Five-year survival for EMP varied by site, with poorest survival in brain/central nervous system EMP as compared with EMP at other sites. To conclude, grade and MIB1 proliferation index help in predicting aggressive course in plasmacytoma. Copyright © 2015 Elsevier Inc. All rights reserved.

Spatial investigation of some uranium minerals using nuclear microprobe

NASA Astrophysics Data System (ADS)

Valter, Anton A.; Knight, Kim B.; Eremenko, Gelij K.; Magilin, Dmitry V.; Ponomarov, Artem A.; Pisansky, Anatoly I.; Romanenko, Alexander V.; Ponomarev, Alexander G.

2018-01-01

In this work, several individual grains of uranium minerals—uraninite with high content of Ca, Ca-rich boltwoodite, growths of uranophane with β-uranophane, and weeksite—from different uranium deposits were studied by a scanning nuclear microprobe. Particle-induced X-ray emission technique provided by the microprobe (µ-PIXE) was carried out to obtain a concentration and 2D distribution of elements in these minerals. In addition, energy dispersive X-ray spectrometry (SEM-EDS) provided by a scanning electron microscope was used. The types of minerals were determined by X-ray diffraction methods. Results of this study improved the understanding of trace elemental composition of the uranium minerals depending on their origin. Obtained signatures could be linked then to the sample provenance. Such data are important for nuclear forensics to identify the ore types and even specific ore bodies, when only small samples may be available for analysis. In this study, the µ-PIXE technique was used for obtaining the 2D distribution of trace elements that are not commonly measured by SEM-EDS at the relevant concentrations. The detected levels and precisions of elements determination by µ-PIXE were also defined. Using µ-PIXE, several micro mineral inclusions such as phosphate with high level of V and Si were identified. The age of the uranium minerals was estimated due to a significant content of radiogenic Pb that provides an additional parameter for determination of the main attributive characteristics of the minerals. This work also showed that due to its high elemental sensitivity the nuclear microprobe can be a new analytical tool for creating a nuclear forensic database from the known uranium deposits and a subsequent analysis of the intercepted illicit materials.

Geochemistry and origin of regional dolomites. Final report

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

Hanson, G.N.; Meyers, W.J.

1995-05-01

The main goal of our research on dolomites has been to better understand the composition of the fluids and processes of the fluid-rock interaction responsible for the formation of massive dolostones occurring over regional scales within sedimentary sequences. Understanding the timing of dolomitization, the fluids responsible for the dolomitization and the timing of the development of porosity has major economic ramifications in that dolomites are major oil reservoirs often having better reservoir properties than associated limestones. Our approach has been to apply trace element, major element, petrographic, crystallographic, stable isotope and radiogenic isotope systems to test models for the originsmore » of dolomites and to give information that may allow us to develop new models. Fluid compositions and processes are evaluated through the use of numerical models which we have developed showing the simultaneous evolution of the trace element and isotope systems during dolomitization. Our research has included the application of B, O, C, Sr, Nd and Pb isotope systematics and the trace elements Mn, Fe St, rare earth elements, Rb, Ba, U, Th, Pb, Zn, Na, Cl, F and SO{sub 4}{sup 2-}. Analyses are possible on individual cements or dolomite types using micro-sampling or microprobe techniques. The microprobe techniques used include synchrotron X-ray microprobe analysis at Brookhaven National Laboratory or electron microprobe at Stony Brook. Lack of a modern analogue for ancient massive dolostones has limited the application of the uniformitarian concept to developing models for the ancient regional dolostones. In addition it has not been possible to synthesize dolomite in the laboratory under conditions similar to the sedimentary or diagenetic possible environments in which the dolomites must have formed.« less

Spatial investigation of some uranium minerals using nuclear microprobe

NASA Astrophysics Data System (ADS)

Valter, Anton A.; Knight, Kim B.; Eremenko, Gelij K.; Magilin, Dmitry V.; Ponomarov, Artem A.; Pisansky, Anatoly I.; Romanenko, Alexander V.; Ponomarev, Alexander G.

2018-06-01

In this work, several individual grains of uranium minerals—uraninite with high content of Ca, Ca-rich boltwoodite, growths of uranophane with β-uranophane, and weeksite—from different uranium deposits were studied by a scanning nuclear microprobe. Particle-induced X-ray emission technique provided by the microprobe (µ-PIXE) was carried out to obtain a concentration and 2D distribution of elements in these minerals. In addition, energy dispersive X-ray spectrometry (SEM-EDS) provided by a scanning electron microscope was used. The types of minerals were determined by X-ray diffraction methods. Results of this study improved the understanding of trace elemental composition of the uranium minerals depending on their origin. Obtained signatures could be linked then to the sample provenance. Such data are important for nuclear forensics to identify the ore types and even specific ore bodies, when only small samples may be available for analysis. In this study, the µ-PIXE technique was used for obtaining the 2D distribution of trace elements that are not commonly measured by SEM-EDS at the relevant concentrations. The detected levels and precisions of elements determination by µ-PIXE were also defined. Using µ-PIXE, several micro mineral inclusions such as phosphate with high level of V and Si were identified. The age of the uranium minerals was estimated due to a significant content of radiogenic Pb that provides an additional parameter for determination of the main attributive characteristics of the minerals. This work also showed that due to its high elemental sensitivity the nuclear microprobe can be a new analytical tool for creating a nuclear forensic database from the known uranium deposits and a subsequent analysis of the intercepted illicit materials.

(R)-[¹¹C]Emopamil as a novel tracer for imaging enhanced P-glycoprotein function.

PubMed

Toyohara, Jun; Okamoto, Mayumi; Aramaki, Hiroki; Zaitsu, Yuto; Shimizu, Isao; Ishiwata, Kiichi

2016-01-01

2-Isopropyl-5-[methyl-(2-phenylethyl)amino]-2-phenylpentanenitrile (emopamil; EMP) is a calcium channel blocker of the phenylalkylamine class, with weak substrate properties for P-glycoprotein (P-gp). A weak substrate for P-gp would be suitable for measuring enhanced P-gp function. This study was performed to synthesise (R)- and (S)-[(11)C]EMP and characterise their properties as P-gp tracers. We synthesised (R)- and (S)-[(11)C]EMP and compared their biodistribution, peripheral metabolism, and effects of the P-gp inhibitor cyclosporine A (CsA, 50 mg/kg). We compared the brain pharmacokinetics of (R)-[(11)C]EMP and (R)-[(11)C]verapamil [(R)-[(11)C]VER] at baseline and CsA pretreatment with small animal positron emission tomography (PET). (R)- and (S)-[(11)C]EMP were synthesised from (R)- and (S)-noremopamil, respectively, by methylation with [(11)C]methyl triflate in the presence of NaOH at room temperature. (R)- and (S)-[(11)C]EMP yields were ~30%, with specific activity>74 GBq/μmol and radiochemical purity>99%. (R)-[(11)C]EMP showed significantly greater uptake in the mouse brain than (S)-[(11)C]EMP. Both showed homogeneous non-stereoselective regional brain distributions. (R)- and (S)-[(11)C]EMP were rapidly metabolised to hydrophilic metabolites. Unchanged plasma (S)-[(11)C]EMP level was significantly lower than that of (R)-[(11)C]EMP 15 minutes post-injection, whilst>88% of radioactivity in the brain was intact at 15 minutes post-injection and was non-stereoselective. CsA pretreatment increased brain activity ~3-fold in mice, but was non-stereoselective. The baseline area-under-the-curve (AUC) of brain radioactivity (0-60 minutes) of (R)-[(11)C]EMP was 2-fold higher than that of (R)-[(11)C]VER, but their AUCs after CsA pretreatment were comparable. (R)-[(11)C]EMP is a novel tracer for imaging P-gp function with higher baseline uptake than (R)-[(11)C]VER. Copyright © 2015 Elsevier Inc. All rights reserved.

Annual FEV1 changes and numbers of circulating endothelial microparticles in patients with COPD: a prospective study

PubMed Central

Takahashi, Toru; Kobayashi, Seiichi; Fujino, Naoya; Suzuki, Takaya; Ota, Chiharu; Tando, Yukiko; Yamada, Mitsuhiro; Yanai, Masaru; Yamaya, Mutsuo; Kurosawa, Shin; Yamauchi, Masanori; Kubo, Hiroshi

2014-01-01

Objective Growing evidence suggests that endothelial injury is involved in the pathophysiology of chronic obstructive pulmonary disease (COPD). Circulating endothelial microparticles (EMPs) increase in patients with COPD because of the presence of endothelial injury. We examined the relationship between EMP number and changes in forced expiratory volume in 1 s (FEV1) in patients with COPD. Design Prospective study. Setting One hospital in Japan. Participants A total 48 outpatients with stable COPD coming to the hospital from September 2010 to September 2011. Primary and secondary outcomes measured Blood samples were collected and vascular endothelial (VE)-cadherin EMPs (CD144+ EMPs), E-selectin EMPs (CD62E+ EMPs) and platelet endothelial cell adhesion molecule EMPs (CD31+/CD41− EMPs) were measured using fluorescence-activated cell sorting. Annual FEV1 changes were evaluated using FEV1 data acquired a year before and a year after sample collection. Results The number of E-selectin and VE-cadherin EMPs showed significant negative correlations with annual FEV1 changes (rs=−0.65, p<0.001, rs=−0.43, p=0.003, respectively). Leucocyte counts tended to be correlated with annual FEV1 changes, but this correlation was not significant (rs=−0.28, p=0.057). There were significant differences in annual FEV1 changes between with and without history of frequent exacerbation (p=0.006), and among Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages (p=0.009). Multiple linear regression analysis revealed E-selectin EMP to be the only significant parameter associated with annual FEV1 changes, independent of VE-cadherin EMP, GOLD stages, leucocyte counts, and history of frequent exacerbation. Receiver operating characteristic curves showed the optimum E-selectin EMP cut-off level for prediction of rapid FEV1 decline (>66 mL/year) to be 153.0/µL (areas under curve 0.78 (95% CI 0.60 to 0.89); sensitivity, 67%; specificity, 81%). Conclusions The high E-selectin EMP levels in stable patients with COPD are predictive of rapid FEV1 decline. Trial registration number UMIN000005168. PMID:24604485

Ancient microbial activity recorded in fracture fillings from granitic rocks (Äspö Hard Rock Laboratory, Sweden).

PubMed

Heim, C; Lausmaa, J; Sjövall, P; Toporski, J; Dieing, T; Simon, K; Hansen, B T; Kronz, A; Arp, G; Reitner, J; Thiel, V

2012-07-01

Fracture minerals within the 1.8-Ga-old Äspö Diorite (Sweden) were investigated for fossil traces of subterranean microbial activity. To track the potential organic and inorganic biosignatures, an approach combining complementary analytical techniques of high lateral resolution was applied to drill core material obtained at -450 m depth in the Äspö Hard Rock Laboratory. This approach included polarization microscopy, time-of-flight secondary ion mass spectrometry (ToF-SIMS), confocal Raman microscopy, electron microprobe (EMP) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The fracture mineral succession, consisting of fluorite and low-temperature calcite, showed a thin (20-100 μm), dark amorphous layer lining the boundary between the two phases. Microscopic investigations of the amorphous layer revealed corrosion marks and, in places, branched tubular structures within the fluorite. Geochemical analysis showed significant accumulations of Si, Al, Mg, Fe and the light rare earth elements (REE) in the amorphous layer. In the same area, ToF-SIMS imaging revealed abundant, partly functionalized organic moieties, for example, C(x)H(y)⁺, C(x)H(y)N⁺, C(x)H(y)O⁺. The presence of such functionalized organic compounds was corroborated by Raman imaging showing bands characteristic of C-C, C-N and C-O bonds. According to its organic nature and the abundance of relatively unstable N- and O- heterocompounds, the organic-rich amorphous layer is interpreted to represent the remains of a microbial biofilm that established much later than the initial cooling of the Precambrian host rock. Indeed, δ¹³C, δ¹⁸O and ⁸⁷Sr/⁸⁶Sr isotope data of the fracture minerals and the host rock point to an association with a fracture reactivation event in the most recent geological past. © 2012 Blackwell Publishing Ltd.

CO2 and H2O Contents of Melt Inclusions from the 1891 Basaltic Balloon Eruption of Foerstner Submarine Volcano, Italy

NASA Astrophysics Data System (ADS)

Balcanoff, J. R.; Carey, S.; Kelley, K. A.; Boesenberg, J. S.

2016-12-01

Eruptions that produce basaltic balloon products are an uncommon eruption style only observed in five cases during historical times. Basaltic balloon products form in gas rich shallow submarine eruptions, which produce large hollow clasts with sufficient buoyancy to float on seawater. Foerstner submarine volcano, off the coast of Pantelleria (Italy), erupted with this style in 1891 and is the only eruption where the vent site (250 m water depth) has been studied and sampled in detail with remotely operated vehicles (ROVs). Here, we report Fournier Transform Infrared Spectroscopy (FTIR) and electron microprobe (EMP) analyses of major elements and dissolved volatiles in melt inclusions from olivine and plagioclase phenocrysts picked from highly vesicular clasts recovered from the seafloor. The trachybasaltic melt is enriched in alkalis with notably high phosphorus (1.82-2.38 wt%), and melt inclusions show elevated H2O concentrations of 0.17 to 1.2 wt.% and highly elevated CO2 concentrations of 928 to 1864 ppm. Coexisting matrix glass is completely degassed with respect to carbon dioxide but has variable water contents up to 0.19 %. The maximum carbon dioxide value implies saturation at 1.5 kb, or 4.5 km below the volcano. Trends in the CO2 and H2O data are most compatible with calculated open system degassing behavior. This is consistent with a proposed balloon formation mechanism involving a hybrid strombolian eruption style with the potential accumulation of gas-rich pockets below the vent as gas bubbles moved upwards independent of the low viscosity basaltic melt. Discharge of the gas-rich pockets led to the discharge of meter-sized slugs of magma with large internal vesicles (several tens of centimeters). A subset of these clasts had bulk densities that were lower than seawater, allowing them to rise to the sea surface where they either exploded or became water saturated and sank back to the seafloor.

Orthopyroxene as a recorder of primitive achondrite petrogenesis: Major-, minor-, and trace-element systematics of orthopyroxene in Lodran. [Abstract only

NASA Technical Reports Server (NTRS)

Papike, J. J.; Spilde, M. N.; Fowler, G. W.; Shearer, C. K.

1994-01-01

Considerable attention has been paid recently to the primitive achondrites because they may form a link between chondrites and more differentiated achondrite meteorites. A recent paper by Miyamoto and Takeda addresses the thermal history of lodranites Yamato 74357 and MAC 88177 as inferred from chemical zoning of pyroxene and olivine determined by electron microprobe analyses. Their results suggested that interstitial melt was present and then extracted. We have taken the analysis of Lodran-type meteorites one step further by incorporating the techniques of Electromagnetic Pulse/Wavelength Dispersive Spectroscopy (EMP/WDS) compositional imaging and scanning ion mass spectroscopy (SIMS) analysis. Orthopyroxene in Lodran is strongly zoned in CaO, Al2O3, TiO2, and Cr2O3 within the last 10-30 microns from the grain boundaries. The rims are reversely zoned in Mg-Fe, exhibiting Mg enrichment, and compositions change from a fairly uniform Wo3En94 within the grains to Wo1En96 at the rims. CaO drops from 1.6 to 0.6 wt% and Al2O3, TiO2, and Cr2O3 exhibit similar depletions. MnO is fairly uniform throughout the grains at around 0.5 wt%. Olivine is also reversely zoned with respect to not only grain boundaries but also to fractures within the grains, giving many olivine grains a complex, patchy zoning pattern. Some of the core-rim trace-element systematics for orthopyroxene are illustrated. Because of the rather narrow zoned rims in Lodran orthopyroxene and the low trace-element abundances, it is difficult to clearly resolve the trace-element systematics. Nevertheless it is evident that the cores are enriched in the incompatible trace elements Ce, Nd, Dy, Er, Yb, Y, and Zr relative to the rims.

Mineralogy and Microstructures of Shock-Induced Melt Veins in Chondrites

NASA Technical Reports Server (NTRS)

Sharp, Thomas G.

2000-01-01

The applicability of phase equilibrium data to the interpretation of shock-induced melt veins can only be tested by a detailed study of melt- vein mineralogy to see how high-pressure assemblages vary as a function of shock conditions inferred from other indicators. We have used transmission electron microscopy (TEM), analytical electron microscopy (AEM), scanning electron microscopy (SEM), electron microprobe analysis (EMA) and optical petrography to characterize the mineralogy, microstructures, and compositions of melt veins and associated high-pressure minerals in shocked chondrites and SNC meteorites. In the processes, we have gained a better understanding of what melt veining can tell us about shock conditions and we have discovered new mineral phases in chondritic and SNC meteorites.

A Comparison of Microstructure and Properties of Equivalent Strength Ingot Metallurgy and Powder Metallurgy 7XXX Aluminum Alloys.

DTIC Science & Technology

1981-08-01

electron microprobe analysis and other laboratory procedures is also acknowledged. The author recognizes the considerable contributions of Ms. Cheryl ...J. Knott , Acta Met., 23, (7), (1975), 841. 473. A. Tetelman and A. McEvily, op. cit. 474. J. Feeney and J. McMillan and R. Wei, Met. Trans., 1, (1970

A geochemical study of macerals from a Miocene lignite and an Eocene bituminous coal, Indonesia

USGS Publications Warehouse

Stankiewicz, B.A.; Kruge, M.A.; Mastalerz, Maria

1996-01-01

Optical and chemical studies of maceral concentrates from a Miocene lignite and an Eocene high-volatile bituminous C coal from southeastern Kalimantan, Indonesia were undertaken using pyro-Lysis, optical, electron microprobe and FTIR techniques Pyrolysis products of vitrinite from bituminous coal were dominated by straight-chain aliphatics and phenols. The huminite of the Miocene lignite produced mostly phenolic compounds upon pyrolysis. Differences in the pyrolysis products between the huminite and vitrinite samples reflect both maturation related and paleobotanical differences. An undefined aliphatic source and/or bacterial biomass were the likely contributors of n-alkyl moieties to the vitrinite. The resinite fraction in the lignite yielded dammar-derived pyrolysis products, as well as aliphatics and phenols as the products of admixed huminite and other liptinites. The optically defined resinite-rich fraction of the bituminous coal from Kalimantan produced abundant n-aliphatic moieties upon pyrolysis, but only two major resin markers (cadalene and 1,6-dimethylnaphthalene). This phenomenon is likely due to the fact that Eocene resins were not dammar-related. Data from the electron microprobe and Fourier transform infrared spectrometry strongly support the results obtained by Py GC MS and microscopy.

Index of Nuclear Weapon Effects Simulators. Sanitized

DTIC Science & Technology

1983-06-01

124 TRESTLE Facility ..................................................... 125 Vertical EMP Simulator ( VEMPS ...82171 SIMULATOR: Vertical EMP Simulator ( VEMPS ) TYPE: EMP AGENCY: US Army LOCATION: HOL1.0’od ridge, V, Research Facility POINT OF CONTACT...DESCRIPTION: The VEMPS facility is I radiating elect, asettc pulse (EMP) stilateor used to expose test obJects to the simulated effects of high altitude EIP

A petrologic and ion microprobe study of a Vigarano Type B refractory inclusion - Evolution by multiple stages of alteration and melting

NASA Technical Reports Server (NTRS)

Macpherson, Glenn J.; Davis, Andrew M.

1993-01-01

A Type B Ca-, Al-rich 6-m-diam inclusion (CAI) found in the Vigarano C3V chondrite was inspected using optical and scanning electron microscopies and ion microprobe analyses. It was found that the primary constituents of the CAI inclusion are (in percent), melilite (52), fassaite, (20), anorthite (18), spinel (10), and trace Fe-Ni metal. It is noted that, while many of the properties of the inclusion indicate solidification from a melt droplet, the Al-26/Mg-26 isotopic systematics and some textural relationships are incompatible with single-stage closed system crystallization of a homogeneous molten droplet, indicating that the history of this inclusion must have been more complex than melt solidification alone. Moreover, there was unusually high content of Na in melilite, suggesting that the droplet did not form by melting of pristine high-temperature nebular condensates.

Microprobe Analysis of Pu-Ga Standards

DOE PAGES

Wall, Angélique D.; Romero, Joseph P.; Schwartz, Daniel

2017-08-04

In order to obtain quantitative analysis using an Electron Scanning Microprobe it is essential to have a standard of known composition. Most elemental and multi-elemental standards can be easily obtained from places like Elemental Scientific or other standards organizations that are NIST (National Institute of Standards and Technology) traceable. It is, however, more challenging to find standards for plutonium. Past work performed in our group has typically involved using the plutonium sample to be analysed as its own standard as long as all other known components of the sample have standards to be compared to [1,2,3]. Finally, this method worksmore » well enough, but this experiment was performed in order to develop a more reliable standard for plutonium using five samples of known chemistry of a plutonium gallium mix that could then be used as the main plutonium and gallium standards for future experiments.« less

Microprobe Analysis of Pu-Ga Standards

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

Wall, Angélique D.; Romero, Joseph P.; Schwartz, Daniel

In order to obtain quantitative analysis using an Electron Scanning Microprobe it is essential to have a standard of known composition. Most elemental and multi-elemental standards can be easily obtained from places like Elemental Scientific or other standards organizations that are NIST (National Institute of Standards and Technology) traceable. It is, however, more challenging to find standards for plutonium. Past work performed in our group has typically involved using the plutonium sample to be analysed as its own standard as long as all other known components of the sample have standards to be compared to [1,2,3]. Finally, this method worksmore » well enough, but this experiment was performed in order to develop a more reliable standard for plutonium using five samples of known chemistry of a plutonium gallium mix that could then be used as the main plutonium and gallium standards for future experiments.« less

Primary melt and fluid inclusions in regenerated crystals and phenocrysts of olivine from kimberlites of the Udachnaya-East Pipe, Yakutia: The problem of the kimberlite melt

NASA Astrophysics Data System (ADS)

Tomilenko, A. A.; Kuzmin, D. V.; Bul'bak, T. A.; Sobolev, N. V.

2017-08-01

The primary melt and fluid inclusions in regenerated zonal crystals of olivine and homogeneous phenocrysts of olivine from kimberlites of the Udachnaya-East pipe, were first studied by means of microthermometry, optic and scanning electron microscopy, electron and ion microprobe analysis (SIMS), inductively coupled plasma mass-spectrometry (ICP MSC), and Raman spectroscopy. It was established that olivine crystals were regenerated from silicate-carbonate melts at a temperature of 1100°C.

A clinical pathologic study of mercurialentis medicamentosus.

PubMed

Garron, L K; Wood, I S; Spencer, W H; Hayes, T L

1976-01-01

Thirty-one patients who used eye drops containing the preservative, phenylmercuric nitrate for from 3 to 15 years, developed a brownish pigmentation of the anterior capsule of the pupillary area. Light and electron microscopic studies on two lenses demonstrated deposits of dense particulate material resembling melanin pigment on and in the anterior capsule of the lens in the area of the pupil. Special studies, including electron microprobe analysis and neutron activation analysis established the presence of mercury in a lens with mercurialentis. No mercury was found in two lenses used as controls.

The Role of the Ion Microprobe in Solid-Earth Geochemistry

NASA Astrophysics Data System (ADS)

Hauri, E. H.

2002-12-01

Despite the early success of the electron microprobe in taking petrology to the micron scale, and the widespread use of mass spectrometers in geochemistry and geochronology, it was not until the mid-1970s that the ion microprobe came into its own as an in situ analytical tool in the Earth sciences. Despite this inauspicious beginning, secondary ion mass spectrometry (SIMS) was widely advertised as a technology that would eventually eclipse thermal ion mass spectrometry (TIMS) in isotope geology. However this was not to happen. While various technical issues in SIMS such as interferences and matrix effects became increasingly clear, an appreciation grew for the complimentary abilities of SIMS and TIMS that, even with the advent of ICP-MS, continues to this day. Today the ion microprobe is capable of abundance measurements in the parts-per-billion range across nearly the entire periodic table, and SIMS stable isotope data quality is now routinely crossing the 1 per mil threshold, all at the micron scale. Much of this success is due to the existence of multi-user community facilities for SIMS research, and the substantial efforts of interested scientists to understand the fundamentals of sputtered ion formation and their application to geochemistry. Recent discoveries of evidence for the existence of ancient crust and oceans, the emergence of life on Earth, the large-scale cycling of surficial materials into the deep Earth, and illumination of fundamental high-pressure phenomena have all been made possible by SIMS, and these (and many more) discoveries owe a debt to the vision of creating and supporting multi-user community facilities for SIMS. The ion microprobe remains an expensive instrument to purchase and maintain, yet it is also exceedingly diverse in application. Major improvements in SIMS, indeed in all mass spectrometry, are visible on the near horizon. Yet the geochemical community cannot depend on commercial manufacturers alone to design and build the next generation of instrumentation for geochemistry. Such will be the role of instrument-minded scientists asking questions that simply cannot be answered by extant means. And it will be multi-user facilities that will make such advancements available to the wider geochemical community.

[Endothelial microparticles (EMP) in physiology and pathology].

PubMed

Sierko, Ewa; Sokół, Monika; Wojtukiewicz, Marek Z

2015-08-18

Endothelial microparticles (EMP) are released from endothelial cells (ECs) in the process of activation and/or apoptosis. They harbor adhesive molecules, enzymes, receptors and cytoplasmic structures and express a wide range of various constitutive antigens, typical for ECs, at their surface. Under physiological conditions the concentration of EMP in the blood is clinically insignificant. However, it was reported that under pathological conditions EMP concentration in the blood might slightly increase and contribute to blood coagulation, angiogenesis and inflammation. It has been shown that EMP directly and indirectly contribute to the activation of blood coagulation. Endothelial microparticles directly participate in blood coagulation through their surface tissue factor (TF) - a major initiator of blood coagulation. Furthermore, EMP exhibit procoagulant potential via expression of negatively charged phospholipids at their surface, which may promote assembly of coagulation enzymes (TF/VII, tenases and prothrombinase complexes), leading to thrombus formation. In addition, they provide a binding surface for coagulation factors: IXa, VIII, Va and IIa. Moreover, it is possible that EMP transfer TF from TF-bearing EMP to activated platelets and monocytes by binding them through adhesion molecules. Also, EMP express von Willebrand factor, which may facilitate platelet aggregation. Apart from their procoagulant properties, it was demonstrated that EMP may express adhesive molecules and metalloproteinases (MMP-2, MMP-9) at their surface and release growth factors, which may contribute to angiogenesis. Additionally, surface presence of C3 and C4 - components of the classical pathway - suggests pro-inflammatory properties of these structures. This article contains a summary of available data on the biology and pathophysiology of endothelial microparticles and their potential role in blood coagulation, angiogenesis and inflammation.

Absence of erythroblast macrophage protein (Emp) leads to failure of erythroblast nuclear extrusion.

PubMed

Soni, Shivani; Bala, Shashi; Gwynn, Babette; Sahr, Kenneth E; Peters, Luanne L; Hanspal, Manjit

2006-07-21

In mammals, the functional unit for definitive erythropoiesis is the erythroblastic island, a multicellular structure composed of a central macrophage surrounded by developing erythroblasts. Erythroblast-macrophage interactions play a central role in the terminal maturation of erythroblasts, including enucleation. One possible mediator of this cell-cell interaction is the protein Emp (erythroblast macrophage protein). We used targeted gene inactivation to define the function of Emp during hematopoiesis. Emp null embryos die perinatally and show profound alterations in the hematopoietic system. A dramatic increase in the number of nucleated, immature erythrocytes is seen in the peripheral blood of Emp null fetuses. In the fetal liver virtually no erythroblastic islands are observed, and the number of F4/80-positive macrophages is substantially reduced. Those present lack cytoplasmic projections and are unable to interact with erythroblasts. Interestingly, wild type macrophages can bind Emp-deficient erythroblasts, but these erythroblasts do not extrude their nuclei, suggesting that Emp impacts enucleation in a cell autonomous fashion. Previous studies have implicated the actin cytoskeleton and its reorganization in both erythroblast enucleation as well as in macrophage development. We demonstrate that Emp associates with F-actin and that this interaction is important in the normal distribution of F-actin in both erythroblasts and macrophages. Thus, Emp appears to be required for erythroblast enucleation and in the development of the mature macrophages. The availability of an Emp null model provides a unique experimental system to study the enucleation process and to evaluate the function of macrophages in definitive erythropoiesis.

Rationale and pre-clinical efficacy of a novel anti-EMP2 antibody for the treatment of invasive breast cancer

PubMed Central

Fu, Maoyong; Maresh, Erin L.; Helguera, Gustavo F.; Kiyohara, Meagan; Qin, Yu; Ashki, Negin; Daniels-Wells, Tracy R.; Aziz, Najib; Gordon, Lynn K.; Braun, Jonathan; Elshimali, Yahya; Soslow, Robert A.; Penichet, Manuel L.; Goodglick, Lee; Wadehra, Madhuri

2014-01-01

Despite significant advances in biology and medicine, the incidence and mortality due to breast cancer world-wide is still unacceptably high. Thus, there is an urgent need to discover new molecular targets. In this paper, we show evidence for a novel target in human breast cancer, the tetraspan protein epithelial membrane protein-2 (EMP2). Using tissue tumor arrays, protein expression of EMP2 was measured and found to be minimal in normal mammary tissue, but it was upregulated in 63% of invasive breast cancer tumors and in 73% of triple negative tumors tested. To test the hypothesis that EMP2 may be a suitable target for therapy, we constructed a fully human IgG1 antibody specific for a conserved domain of human and murine EMP2. Treatment of breast cancer cells with the anti-EMP2 IgG1 significantly inhibited EMP2 mediated signaling, blocked FAK/Src signaling, inhibited invasion, and promoted apoptosis in vitro. In both human xenograft and syngeneic metastatic tumor monotherapy models, anti-EMP2 IgG1 retarded tumor growth without detectable systemic toxicity. This anti-tumor effect was in part attributable to a potent ADCC response as well as direct cytotoxicity induced by the monoclonal antibody. Together, these results identify EMP2 as a novel therapeutic target for invasive breast cancer. PMID:24448822

Rationale and preclinical efficacy of a novel anti-EMP2 antibody for the treatment of invasive breast cancer.

PubMed

Fu, Maoyong; Maresh, Erin L; Helguera, Gustavo F; Kiyohara, Meagan; Qin, Yu; Ashki, Negin; Daniels-Wells, Tracy R; Aziz, Najib; Gordon, Lynn K; Braun, Jonathan; Elshimali, Yahya; Soslow, Robert A; Penichet, Manuel L; Goodglick, Lee; Wadehra, Madhuri

2014-04-01

Despite significant advances in biology and medicine, the incidence and mortality due to breast cancer worldwide is still unacceptably high. Thus, there is an urgent need to discover new molecular targets. In this article, we show evidence for a novel target in human breast cancer, the tetraspan protein epithelial membrane protein-2 (EMP2). Using tissue tumor arrays, protein expression of EMP2 was measured and found to be minimal in normal mammary tissue, but it was upregulated in 63% of invasive breast cancer tumors and in 73% of triple-negative tumors tested. To test the hypothesis that EMP2 may be a suitable target for therapy, we constructed a fully human immunoglobulin G1 (IgG1) antibody specific for a conserved domain of human and murine EMP2. Treatment of breast cancer cells with the anti-EMP2 IgG1 significantly inhibited EMP2-mediated signaling, blocked FAK/Src signaling, inhibited invasion, and promoted apoptosis in vitro. In both human xenograft and syngeneic metastatic tumor monotherapy models, anti-EMP2 IgG1 retarded tumor growth without detectable systemic toxicity. This antitumor effect was, in part, attributable to a potent antibody-dependent cell-mediated cytotoxicity response as well as direct cytotoxicity induced by the monoclonal antibody. Together, these results identify EMP2 as a novel therapeutic target for invasive breast cancer.

Super-achromatic microprobe for ultrahigh-resolution endoscopic OCT imaging at 800 nm (Conference Presentation)

NASA Astrophysics Data System (ADS)

Yuan, Wu; Alemohammad, Milad; Yu, Xiaoyun; Yu, Shaoyong; Li, Xingde

2016-03-01

In this paper, we report a super-achromatic microprobe made with fiber-optic ball lens to enable ultrahigh-resolution endoscopic OCT imaging. An axial resolution of ~2.4 µm (in air) can be achieved with a 7-fs Ti:Sapphire laser. The microprobe has minimal astigmatism which affords a high transverse resolution of ~5.6 µm. The miniaturized microprobe has an outer diameter of ~520 µm including the encasing metal guard and can be used to image small luminal organs. The performance of the ultrahigh-resolution OCT microprobe was demonstrated by imaging rat esophagus, guinea pig esophagus, and mouse rectum in vivo.

Exploring the Early Chemical Evolution of the Milky Way with LAMOST and Subaru

NASA Astrophysics Data System (ADS)

Li, Haining; Aoki, Wako; Honda, Satoshi; Zhao, Gang; Suda, Takuma; Christlieb, Norbert

Extremely Metal-Poor (EMP) stars ([Fe/H] < -3.0) provide fundamental evidence on the nucleosynthesis and enrichment of the first stars and supernovae. LAMOST will observe 6 million Galactic stars through a 5-year spectroscopic survey, and thus provide an unprecedented chance to enlarge the EMP star sample. In 2014, a joint project on EMP stars was initiated with the LAMOST survey and Subaru follow-up observation. So far, more than 70 EMP stars have been found and confirmed, including identifications of a number of chemically interesting objects: three UMP (ultra metal-poor) stars with [Fe/H] ˜ -4.0, including the second UMP turnoff star with Li detection; a super Li-rich (A(Li) = +3) EMP giant, which is the most extreme example of Li enhancement in red giants known to date; a few EMP stars showing extreme enhancements in neutron-capture elements. Statistics of a large sample of EMP stars will constrain formation of the Milky Way halo.

78 FR 58605 - Proposed Collection; Comment Request for Form 8453-EMP, Form 8453-F, Form 8453-FE, Form 8879-F...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-24

... Declaration and Signature for Electronic and Magnetic Made Filing; Form 8453-FE, U.S. Estate or Trust... information or copies of the form and instructions should be directed to Gerald J. Shields, Internal Revenue....Shields@irs.gov . SUPPLEMENTARY INFORMATION: Title: Employment Tax Declaration for an IRS e-file Return...

Study to assess the effects of magnetohydrodynamic electromagnetic pulse on electric power systems, phase 1, volume 3

NASA Astrophysics Data System (ADS)

Legro, J. R.; Abi-Samra, N. C.; Tesche, F. M.

1985-05-01

In addition to the initial transients designated as fast transient high-altitude EMP (HEMP) and intermediate time EMP, electromagnetic signals are also perceived at times from seconds to hundreds of seconds after a high-altitude nuclear burst. This signal was defined by the term magnetohydrodynamic-electromagnetic pulse (MHD-EMP). The MHD-EMP phenomena was detected in actual weapon tests and predicted from theoretical models. A preliminary research effort to investigate the nature and coupling of the MHD-EMP environments to electric power systems documented the construction of approximate system response network models, and the development of a unified methodology to assess equipment and systematic vulnerability are defined. The MHD-EMP environment is compared to a qualitatively similar natural event, the electromagnetic environment produced by geomagnetic storms.

EMP-002a Phase Shift through the Ionosphere

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

Soltz, R.; Simons, D.; Fenimore, E.

2015-10-20

In this note we review the derivation and use of the Ionospheric Transfer Function (ITF) in the DIO- RAMA model to calculate the propagation of a broad band ElectroMagnetic Pulse (EMP) through the Ionosphere in the limit of geometric optics. This note is intended to resolve a misunderstanding between the NDS VVA and EMP modeling teams regarding the appropriate use of the phase and group velocities in DIORAMA. The di erent approaches are documented in EMP-002 note, \\Phase vs. Group" [1], generated by the LLNL DIORAMA VVA team, and the subsequent response from the DIORAMA EMP modeling team' [2].

Comprehensive assessment of exposures to elongate mineral particles in the taconite mining industry.

PubMed

Hwang, Jooyeon; Ramachandran, Gurumurthy; Raynor, Peter C; Alexander, Bruce H; Mandel, Jeffrey H

2013-10-01

Since the 1970s, concerns have been raised about elevated rates of mesothelioma in the vicinity of the taconite mines in the Mesabi Iron Range. However, insufficient quantitative exposure data have hampered investigations of the relationship between cumulative exposures to elongate mineral particles (EMP) in taconite dust and adverse health effects. Specifically, no research on exposure to taconite dust, which includes EMP, has been conducted since 1990. This article describes a comprehensive assessment of present-day exposures to total and amphibole EMP in the taconite mining industry. Similar exposure groups (SEGs) were established to assess present-day exposure levels and buttress the sparse historical data. Personal samples were collected to assess the present-day levels of worker exposures to EMP at six mines in the Mesabi Iron Range. The samples were analyzed using National Institute for Occupational Safety and Health (NIOSH) methods 7400 and 7402. For many SEGs in several mines, the exposure levels of total EMP were higher than the NIOSH Recommended Exposure Limit (REL). However, the total EMP classification includes not only the asbestiform EMP and their non-asbestiform mineral analogs but also other minerals because the NIOSH 7400 cannot differentiate between these. The concentrations of amphibole EMP were well controlled across all mines and were much lower than the concentrations of total EMP, indicating that amphibole EMP are not major components of taconite EMP. The levels are also well below the NIOSH REL of 0.1 EMP cc(-1). Two different approaches were used to evaluate the variability of exposure between SEGs, between workers, and within workers. The related constructs of contrast and homogeneity were calculated to characterize the SEGs. Contrast, which is a ratio of between-SEG variability to the sum of between-SEG and between-worker variability, provides an overall measure of whether there are distinctions between the SEGs. Homogeneity, which is the ratio of the within-worker variance component to the sum of the between-worker and within-worker variance components, provides an overall measure of how similar exposures are for workers within an SEG. Using these constructs, it was determined that the SEGs are formed well enough when grouped by mine for both total and amphibole EMP to be used for epidemiological analysis.

Nonreciprocal quantum Hall devices with driven edge magnetoplasmons in two-dimensional materials

NASA Astrophysics Data System (ADS)

Bosco, S.; DiVincenzo, D. P.

2017-05-01

We develop a theory that describes the response of nonreciprocal devices employing two-dimensional materials in the quantum Hall regime capacitively coupled to external electrodes. As the conduction in these devices is understood to be associated to the edge magnetoplasmons (EMPs), we first investigate the EMP problem by using the linear response theory in the random phase approximation. Our model can incorporate several cases that were often treated on different grounds in literature. In particular, we analyze plasmonic excitations supported by a smooth and sharp confining potential in a two-dimensional electron gas, and in monolayer graphene, and we point out the similarities and differences in these materials. We also account for a general time-dependent external drive applied to the system. Finally, we describe the behavior of a nonreciprocal quantum Hall device: the response contains additional resonant features, which were not foreseen from previous models.

B-Cell Responses to Pregnancy-Restricted and -Unrestricted Plasmodium falciparum Erythrocyte Membrane Protein 1 Antigens in Ghanaian Women Naturally Exposed to Malaria Parasites

PubMed Central

Ampomah, Paulina; Stevenson, Liz; Ofori, Michael F.; Barfod, Lea

2014-01-01

Protective immunity to Plasmodium falciparum malaria acquired after natural exposure is largely antibody mediated. IgG-specific P. falciparum EMP1 (PfEMP1) proteins on the infected erythrocyte surface are particularly important. The transient antibody responses and the slowly acquired protective immunity probably reflect the clonal antigenic variation and allelic polymorphism of PfEMP1. However, it is likely that other immune-evasive mechanisms are also involved, such as interference with formation and maintenance of immunological memory. We measured PfEMP1-specific antibody levels by enzyme-linked immunosorbent assay (ELISA) and memory B-cell frequencies by enzyme-linked immunosorbent spot (ELISPOT) assay in a cohort of P. falciparum-exposed nonpregnant Ghanaian women. The antigens used were a VAR2CSA-type PfEMP1 (IT4VAR04) with expression restricted to parasites infecting the placenta, as well as two commonly recognized PfEMP1 proteins (HB3VAR06 and IT4VAR60) implicated in rosetting and not pregnancy restricted. This enabled, for the first time, a direct comparison in the same individuals of immune responses specific for a clinically important parasite antigen expressed only during well-defined periods (pregnancy) to responses specific for comparable antigens expressed independent of pregnancy. Our data indicate that PfEMP1-specific B-cell memory is adequately acquired even when antigen exposure is infrequent (e.g., VAR2CSA-type PfEMP1). Furthermore, immunological memory specific for VAR2CSA-type PfEMP1 can be maintained for many years without antigen reexposure and after circulating antigen-specific IgG has disappeared. The study provides evidence that natural exposure to P. falciparum leads to formation of durable B-cell immunity to clinically important PfEMP1 antigens. This has encouraging implications for current efforts to develop PfEMP1-based vaccines. PMID:24566620

Flow cytometric detection of endothelial microparticles (EMP): effects of centrifugation and storage alter with the phenotype studied.

PubMed

van Ierssel, Sabrina H; Van Craenenbroeck, Emeline M; Conraads, Viviane M; Van Tendeloo, Viggo F; Vrints, Christiaan J; Jorens, Philippe G; Hoymans, Vicky Y

2010-04-01

Endothelial microparticles (EMP) are released into the circulation in case of endothelial disturbance, and are therefore increasingly investigated as a biomarker reflecting disease activity. Numerous pre-analytic methods have been proposed for their flow cytometric enumeration, but standardization is still lacking. In this study we evaluated the influence of centrifugation and storage conditions on EMP quantification. Platelet-poor plasma (PPP) from 10 healthy volunteers was prepared by centrifugation at 1,550 g for 20 minutes twice. A first aliquot of PPP was analyzed immediately, a second after storage at 4 degrees C for 7 hours. A third and fourth aliquot were snap-frozen and stored at -80 degrees C for 7 and 28 days. A final aliquot was further centrifuged at 10,000g for 10 minutes and analyzed immediately. EMP were defined as CD31+CD42b-, CD62E+, CD144+ or CD144+CD105+ particles, smaller than 1.0 microm. High speed centrifugation led to a significant loss of CD31+CD42b- EMP (p=0.004). A good correlation between PPP and high speed centrifuged PPP was only found for CD144+ EMP (Kendall tau b=0.611, p=0.025). Storage at 4 degrees C did not affect EMP quantification. However, freezing at -80 degrees C increased CD31+CD42b- and CD62E+ EMP counts, and lowered CD144+ EMP (p<0.05). Nevertheless, the agreement among the different storage conditions was relatively good (Kendall coefficient of concordance >0.487; p<0.05). The flow cytometric detection of EMP varies with the centrifugation protocol and the storage method used, and these changes also depend on the phenotype studied. The results of this study caution against comparing study results gathered with different EMP laboratory protocols. (c) 2010 Elsevier Ltd. All rights reserved.

Endothelial Microparticles (EMP) for the Assessment of Endothelial Function: An In Vitro and In Vivo Study on Possible Interference of Plasma Lipids

PubMed Central

van Ierssel, Sabrina H.; Hoymans, Vicky Y.; Van Craenenbroeck, Emeline M.; Van Tendeloo, Viggo F.; Vrints, Christiaan J.; Jorens, Philippe G.; Conraads, Viviane M.

2012-01-01

Background Circulating endothelial microparticles (EMP) reflect the condition of the endothelium and are of increasing interest in cardiovascular and inflammatory diseases. Recently, increased numbers of EMP following oral fat intake, possibly due to acute endothelial injury, have been reported. On the other hand, the direct interference of lipids with the detection of EMP has been suggested. This study aimed to investigate the effect of lipid-rich solutions, commonly administered in clinical practice, on the detection, both in vitro and in vivo, of EMP. Methods For the in vitro assessment, several lipid-rich solutions were added to whole blood of healthy subjects (n = 8) and patients with coronary heart disease (n = 5). EMP (CD31+/CD42b−) were detected in platelet poor plasma by flow cytometry. For the in vivo study, healthy volunteers were evaluated on 3 different study-days: baseline evaluation, following lipid infusion and after a NaCl infusion. EMP quantification, lipid measurements and peripheral arterial tonometry were performed on each day. Results Both in vitro addition and in vivo administration of lipids significantly decreased EMP (from 198.6 to 53.0 and from 272.6 to 90.6/µl PPP, respectively, p = 0.001 and p = 0.012). The EMP number correlated inversely with the concentration of triglycerides, both in vitro and in vivo (r = −0.707 and −0.589, p<0.001 and p = 0.021, respectively). The validity of EMP as a marker of endothelial function is supported by their inverse relationship with the reactive hyperemia index (r = −0.758, p = 0.011). This inverse relation was confounded by the intravenous administration of lipids. Conclusion The confounding effect of high circulating levels of lipids, commonly found in patients that receive intravenous lipid-based solutions, should be taken into account when flow cytometry is used to quantify EMP. PMID:22359595

Endothelial microparticles (EMP) for the assessment of endothelial function: an in vitro and in vivo study on possible interference of plasma lipids.

PubMed

van Ierssel, Sabrina H; Hoymans, Vicky Y; Van Craenenbroeck, Emeline M; Van Tendeloo, Viggo F; Vrints, Christiaan J; Jorens, Philippe G; Conraads, Viviane M

2012-01-01

Circulating endothelial microparticles (EMP) reflect the condition of the endothelium and are of increasing interest in cardiovascular and inflammatory diseases. Recently, increased numbers of EMP following oral fat intake, possibly due to acute endothelial injury, have been reported. On the other hand, the direct interference of lipids with the detection of EMP has been suggested. This study aimed to investigate the effect of lipid-rich solutions, commonly administered in clinical practice, on the detection, both in vitro and in vivo, of EMP. For the in vitro assessment, several lipid-rich solutions were added to whole blood of healthy subjects (n = 8) and patients with coronary heart disease (n = 5). EMP (CD31+/CD42b-) were detected in platelet poor plasma by flow cytometry. For the in vivo study, healthy volunteers were evaluated on 3 different study-days: baseline evaluation, following lipid infusion and after a NaCl infusion. EMP quantification, lipid measurements and peripheral arterial tonometry were performed on each day. Both in vitro addition and in vivo administration of lipids significantly decreased EMP (from 198.6 to 53.0 and from 272.6 to 90.6/µl PPP, respectively, p = 0.001 and p = 0.012). The EMP number correlated inversely with the concentration of triglycerides, both in vitro and in vivo (r = -0.707 and -0.589, p<0.001 and p = 0.021, respectively). The validity of EMP as a marker of endothelial function is supported by their inverse relationship with the reactive hyperemia index (r = -0.758, p = 0.011). This inverse relation was confounded by the intravenous administration of lipids. The confounding effect of high circulating levels of lipids, commonly found in patients that receive intravenous lipid-based solutions, should be taken into account when flow cytometry is used to quantify EMP.

Electromagnetic-guided placement of nasoduodenal feeding tubes versus endoscopic placement: a randomized, multicenter trial.

PubMed

Kappelle, Wouter F W; Walter, Daisy; Stadhouders, Paul H; Jebbink, Hendrik J A; Vleggaar, Frank P; van der Schaar, Peter J; Kappelle, Jan Willem; van der Tweel, Ingeborg; Van den Broek, Medard F M; Wessels, Frank J; Siersema, Peter D; Monkelbaan, Jan F

2018-01-01

Electromagnetic-guided placement (EMP) of a nasoduodenal feeding tube by trained nurses is an attractive alternative to EGD-guided placement (EGDP). We aimed to compare EMP and EGDP in outpatients, ward patients, and critically ill patients with normal upper GI anatomy. In 3 centers with no prior experience in EMP, patients were randomized to placement of a single-lumen nasoduodenal feeding tube either with EGDP or EMP. The primary endpoint was post-pyloric position of the tube on abdominal radiography. Patients were followed for 10 days to assess patency and adverse events. The analyses were performed according to the intention-to-treat principle. In total, 160 patients were randomized to EGDP (N = 76) or EMP (N = 84). Three patients withdrew informed consent, and no abdominal radiography was performed in 2 patients. Thus, 155 patients (59 intensive care unit, 38%) were included in the analyses. Rates of post-pyloric tube position between EGDP and EMP were comparable (79% vs 82%, odds ratio 1.16; 90% confidence interval, 0.58-2.38; P = .72). Adverse events were observed in 4 patients after EMP (hypoxia, GI blood loss, atrial fibrillation, abdominal pain) and in 4 after EGDP (epistaxis N = 2, GI blood loss, hypoxia). Costs of tube placements were lower for EMP compared with EGDP: $519.09 versus $622.49, respectively (P = .04). Success rates and safety of EMP and EGDP in patients with normal upper GI anatomy were comparable. Lower costs and potential logistic advantages may drive centers to adopt EMP as their new standard of care. (Clinical trial registration number: NTR4286.). Copyright © 2018 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

The association between endothelial microparticles and inflammation in patients with systemic sclerosis and Raynaud's phenomenon as detected by functional imaging.

PubMed

Jung, Christian; Drummer, Karl; Oelzner, Peter; Figulla, Hans R; Boettcher, Joachim; Franz, Marcus; Betge, Stefan; Foerster, Martin; Wolf, Gunter; Pfeil, Alexander

2015-01-01

Systemic sclerosis (SSc) is a systemic, autoimmune connective tissue disease characterized by vasculopathy and microvascular changes. Fluorescence Optical Imaging (FOI) is a technique used to assess inflammation in patients with arthritis; in this study FOI is used to quantify inflammation in the hand. Endothelial Microparticle (EMP) can reflect damage or activation of the endothelium but also actively modulate processes of inflammation, coagulation and vascular function. The aim of the present study was to quantify EMP and FOI, to determine an association between these microparticles and inflammation and to endothelial function. EMP were quantified in plasma samples of 25 patients (24 female, 1 male, age: 41 ± 9 years) with SSc using flow cytometry. EMP was defined as CD31+/CD42- MP, and CD62+ MP. Perivascular inflammation was assessed using fluorescence optical imaging (FOI) of the hand. Macrovascular endothelial function was non-invasively estimated using the Endopat system. Plasma levels of CD31+/CD42- EMP and CD62+ EMP were lower in patients with SSc compared to controls (both p <  0.05). An impaired endothelial function with an increased hyperemia index was observed. A strong association could be demonstrated between CD62+ EMP and perivascular soft tissue inflammation as assessed by the FOI global score (Spearman, p = 0.002, r = 0.61). EMP indicate molecular vascular damage in SSc; in this study a strong association between EMP and perivascular inflammation as quantified by FOI is demonstrated. Consequently EMP, using FOI, may be a potential marker benefitting the diagnosis and therapy monitoring of patients with SSc with associated Raynaud's phenomenon.

Endothelial microparticles reduce ICAM-1 expression in a microRNA-222-dependent mechanism

PubMed Central

Jansen, Felix; Yang, Xiaoyan; Baumann, Katharina; Przybilla, David; Schmitz, Theresa; Flender, Anna; Paul, Kathrin; Alhusseiny, Adil; Nickenig, Georg; Werner, Nikos

2015-01-01

Endothelial microparticles (EMP) are released from activated or apoptotic endothelial cells (ECs) and can be taken up by adjacent ECs, but their effect on vascular inflammation after engulfment is largely unknown. We sought to determine the role of EMP in EC inflammation. In vitro, EMP treatment significantly reduced tumour necrosis factor-α-induced endothelial intercellular adhesion molecule (ICAM)-1 expression on mRNA and protein level, whereas there was no effect on vascular cell adhesion molecule-1 expression. Reduced ICAM-1 expression after EMP treatment resulted in diminished monocyte adhesion in vitro. In vivo, systemic treatment of ApoE−/− mice with EMP significantly reduced murine endothelial ICAM-1 expression. To explore the underlying mechanisms, Taqman microRNA array was performed and microRNA (miR)-222 was identified as the strongest regulated miR between EMP and ECs. Following experiments demonstrated that miR-222 was transported into recipient ECs by EMP and functionally regulated expression of its target protein ICAM-1 in vitro and in vivo. After simulating diabetic conditions, EMP derived from glucose-treated ECs contained significantly lower amounts of miR-222 and showed reduced anti-inflammatory capacity in vitro and in vivo. Finally, circulating miR-222 level was diminished in patients with coronary artery disease (CAD) compared to patients without CAD. EMPs promote anti-inflammatory effects in vitro and in vivo by reducing endothelial ICAM-1 expression via the transfer of functional miR-222 into recipient cells. In pathological hyperglycaemic conditions, EMP-mediated miR-222-dependent anti-inflammatory effects are reduced. PMID:26081516

Low Frequency Electromagnetic Pulse and Explosions

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

Sweeney, J J

2011-02-01

This paper reviews and summarizes prior work related to low frequency (< 100 Hz) EMP (ElectroMagnetic Pulse) observed from explosions. It focuses on how EMP signals might, or might not, be useful in monitoring underground nuclear tests, based on the limits of detection, and physical understanding of these signals. In summary: (1) Both chemical and nuclear explosions produce an EMP. (2) The amplitude of the EMP from underground explosions is at least two orders of magnitude lower than from above ground explosions and higher frequency components of the signal are rapidly attenuated due to ground conductivity. (3) In general, inmore » the near field, that is distances (r) of less than 10s of kilometers from the source, the amplitude of the EMP decays approximately as 1/r{sup 3}, which practically limits EMP applications to very close (<{approx}1km) distances. (4) One computational model suggests that the EMP from a decoupled nuclear explosion may be enhanced over the fully coupled case. This has not been validated with laboratory or field data. (5) The magnitude of the EMP from an underground nuclear explosion is about two orders of magnitude larger than that from a chemical explosion, and has a larger component of higher frequencies. In principle these differences might be used to discriminate a nuclear from a chemical explosion using sensors at very close (<{approx}1 km) distances. (6) Arming and firing systems (e.g. detonators, exploding bridge wires) can also produce an EMP from any type of explosion. (7) To develop the understanding needed to apply low frequency EMP to nuclear explosion monitoring, it is recommended to carry out a series of controlled underground chemical explosions with a variety of sizes, emplacements (e.g. fully coupled and decoupled), and arming and firing systems.« less

Endothelial microparticles reduce ICAM-1 expression in a microRNA-222-dependent mechanism.

PubMed

Jansen, Felix; Yang, Xiaoyan; Baumann, Katharina; Przybilla, David; Schmitz, Theresa; Flender, Anna; Paul, Kathrin; Alhusseiny, Adil; Nickenig, Georg; Werner, Nikos

2015-09-01

Endothelial microparticles (EMP) are released from activated or apoptotic endothelial cells (ECs) and can be taken up by adjacent ECs, but their effect on vascular inflammation after engulfment is largely unknown. We sought to determine the role of EMP in EC inflammation. In vitro, EMP treatment significantly reduced tumour necrosis factor-α-induced endothelial intercellular adhesion molecule (ICAM)-1 expression on mRNA and protein level, whereas there was no effect on vascular cell adhesion molecule-1 expression. Reduced ICAM-1 expression after EMP treatment resulted in diminished monocyte adhesion in vitro. In vivo, systemic treatment of ApoE-/- mice with EMP significantly reduced murine endothelial ICAM-1 expression. To explore the underlying mechanisms, Taqman microRNA array was performed and microRNA (miR)-222 was identified as the strongest regulated miR between EMP and ECs. Following experiments demonstrated that miR-222 was transported into recipient ECs by EMP and functionally regulated expression of its target protein ICAM-1 in vitro and in vivo. After simulating diabetic conditions, EMP derived from glucose-treated ECs contained significantly lower amounts of miR-222 and showed reduced anti-inflammatory capacity in vitro and in vivo. Finally, circulating miR-222 level was diminished in patients with coronary artery disease (CAD) compared to patients without CAD. EMPs promote anti-inflammatory effects in vitro and in vivo by reducing endothelial ICAM-1 expression via the transfer of functional miR-222 into recipient cells. In pathological hyperglycaemic conditions, EMP-mediated miR-222-dependent anti-inflammatory effects are reduced. © 2015 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

Zinc in Entamoeba invadens.

NASA Technical Reports Server (NTRS)

Morgan, R. S.; Sattilaro, R. F.

1972-01-01

Atomic absorption spectroscopy, electron microprobe analysis, and dithizone staining of trophozoites and cysts of Entamoeba invadens demonstrate that these cells have a high concentration of zinc (approximately one picogram per cell or 1% of their dry weight). In the cysts of this organism, the zinc is confined to the chromatoid bodies, which previous work has shown to contain crystals of ribosomes. The chemical state and function of this zinc are unknown.

Petrographic and petrological study of lunar rock materials

NASA Technical Reports Server (NTRS)

Winzer, S. R.

1977-01-01

Impact melts and breccias from the Apollo 15 and 16 landing sites were examined optically and by electron microscope/microprobe. Major and trace element abundances were determined for selected samples. Apollo 16 breccias contained impact melts, metamorphic and primary igneous rocks. Metamorphic rocks may be the equivalents of the impact melts. Apollo 15 breccias studied were fragment-laden melts derived from gabbro and more basalt target rocks.

Petrology of 60035 - Evolution of a polymict ANT breccia

NASA Technical Reports Server (NTRS)

Warner, R. D.; Taylor, G. J.; Keil, K.

1980-01-01

Extensive analysis of the lunar rock sample 60035 with optical microscopy and electron microprobe methods show it to be a polymict ANT breccia partly coated with glass, containing abundant clasts which have troctolitic/noritic anorthosite compositions. At least two episodes of crushing and mixing were involved in the petrogenesis of 60035, and annealing and mineral equilibration have not been extensive since the formation of the breccia.

[Apoptosis of human lung carcinoma cell line GLC-82 induced by high power electromagnetic pulse].

PubMed

Cao, Xiao-zhe; Zhao, Mei-lan; Wang, De-wen; Dong, Bo

2002-09-01

Electromagnetic pulse (EMP) could be used for sterilization of food and the efficiency is higher than 2450 MHz continuous microwave done. This study was designed to evaluate the effect of electromagnetic pulse (EMP) on apoptosis of human lung carcinoma cell line GLC-82, so that to explore and develop therapeutic means for cancer. The injury changes in GLC-82 cells after irradiated with EMP (electric field intensity was 60 kV/m, 5 pulses/2 min) were analyzed by cytometry, MTT chronometry, and flow cytometry. The immunohistochemical SP staining was used to determine the expressions of bcl-2 protein and p53 protein. The stained positive cells were analyzed by CMIAS-II image analysis system at a magnification 400. All data were analyzed by SPSS8.0 software. EMP could obviously inhibited proliferation and activity of lung carcinoma cell line GLC-82. The absorbance value (A570) of MTT decreased immediately, at 0 h, 1 h, and 6 h after the GLC-82 cells irradiated by EMP as compared with control group. The highest apoptosis rate was found to reach 13.38% by flow cytometry at 6 h after EMP irradiation. Down-regulation of bcl-2 expression and up-regulation of p53 expression were induced by EMP. EMP promotes apoptosis of GLC-82 cells. At same time, EMP can down-regulate bcl-2 expression and up-regulate p53 expression in GLC-82 cells. The bcl-2 and the p53 protein may involve the apoptotic process.

Elevated circulating endothelial cell-derived microparticle levels in patients with liver cirrhosis: a preliminary report

PubMed Central

Simon, Krzysztof Adam; Pazgan-Simon, Monika

2015-01-01

Aim of the study To determine plausible associations between liver cirrhosis and circulating endothelial cell-derived microparticles (EMPs), vascular endothelial growth factor (VEGF) levels and plasma nitric oxide (NO) metabolites. Material and methods Sixty patients with cirrhosis and 20 healthy control subjects were enrolled in the study. Circulating EMPs from platelet-poor plasma samples were examined by flow cytometry. These microparticles were categorized into endothelial cell-derived activated MPs (EMP-ac) (CD31+ CD42b– AN-V–) and endothelial cell-derived apoptotic MPs (EMP-ap) (CD31+ CD42b– AN-V+). Plasma VEGF levels were measured by enzyme-linked immunosorbent assay. Plasma NO metabolites (NOx–) levels were determined using a Greiss reaction method. Results Compared with the healthy control subjects, the patients with cirrhosis showed a significant increase in plasma levels of both phenotypes of EMPs. When the presence of ascites was considered, the plasma levels of EMP-ap were higher (p < 0.01), as well as NOx– (p < 0.05). EMP-ap positively correlated with VEGF level in all cirrhotic patients and this correlation was stronger in decompensated cirrhotic patients. In multivariate logistic regression analysis, the independent factors associated with the presence of ascites were high EMP-ap levels and elevated VEGF levels. Conclusions Elevated plasma levels of EMP-ap in addition to high levels of VEGF might be considered as valuable parameters for predicting the occurrence of ascites in cirrhotic patients. PMID:28856256

Mesothelioma and other lung disease in taconite miners; the uncertain role of non-asbestiform EMP.

PubMed

Mandel, Jeffrey H; Odo, Nnaemeka U

2018-04-10

The purpose of this paper was to assess the role of non-asbestiform amphibole EMPs in the etiology of mesotheliomas and other lung disease in taconite (iron ore) miners. Increased mesothelioma rates have been described in Minnesota taconite workers since the late 1990s. Currently, over 100 cases have been reported by the Minnesota Department of Health within the complete cohort of miners in Minnesota. Geologic sampling has indicated that only the eastern part of the iron range contains non-asbestiform amphibole elongate mineral particles (EMPs), in close proximity to the ore. This type of EMP has been less studied and also exists in talc and gold mining. A series of investigations into the state's taconite industry have been recently completed. Results from a cohort mortality study indicated an SMR of 2.77 (95% CI = 1.87-3.96) for mesothelioma. In a case-control study, the odds ratio for mesothelioma for high vs. low EMP exposure was 2.25 (5% CI = 1.13-4.5) but EMPs in this study were counted by phase contrast microscopy. Odds ratios were not elevated in mines located in the eastern part of the Mesabi iron range. The overall findings suggest that mesothelioma in taconite miners is related to EMP exposure. Because of the way EMPs were counted, results from these studies cannot allow a firm conclusion about the association between EMP exposure and the reported excess mesothelioma. Copyright © 2018 Elsevier Inc. All rights reserved.

Classification of extremely metal-poor stars: absent region in A(C)-[Fe/H] plane and the role of dust cooling

NASA Astrophysics Data System (ADS)

Chiaki, Gen; Tominaga, Nozomu; Nozawa, Takaya

2017-11-01

Extremely metal-poor (EMP) stars are the living fossils with records of chemical enrichment history at the early epoch of galaxy formation. By the recent large observation campaigns, statistical samples of EMP stars have been obtained. This motivates us to reconsider their classification and formation conditions. From the observed lower limits of carbon and iron abundances of Acr(C) ∼ 6 and [Fe/H]cr ∼ -5 for C-enhanced EMP (CE-EMP) and C-normal EMP (CN-EMP) stars, we confirm that gas cooling by dust thermal emission is indispensable for the fragmentation of their parent clouds to form such low mass, i.e. long-lived stars, and that the dominant grain species are carbon and silicate, respectively. We constrain the grain radius r_i^cool of a species i and condensation efficiency fij of a key element j as r_C^cool / f_C,C = 10 {μ m} and r_Sil^cool / f_Sil,Mg = 0.1 {μ m} to reproduce Acr(C) and [Fe/H]cr, which give a universal condition 10[C/H] - 2.30 + 10[Fe/H] > 10-5.07 for the formation of every EMP star. Instead of the conventional boundary [C/Fe] = 0.7 between CE-EMP and CN-EMP stars, this condition suggests a physically meaningful boundary [C/Fe]b = 2.30 above and below which carbon and silicate grains are dominant coolants, respectively.

The expression and function of epithelial membrane protein 1 in laryngeal carcinoma.

PubMed

Li, Hong; Zhang, Xiaowen; Jiang, Xuejun; Ji, Xu

2017-01-01

In this study, we compared the expression of epithelial membrane protein 1 (EMP1) on the steady-state mRNA level (by quantitative real-time PCR) and on the protein level (by western immunoblot and immunohistochemistry) in 51 pairs of laryngeal carcinoma tissues and matched cancer-free peritumor tissues, and we analyzed the correlation between EMP1 expression and different clinicopathological factors. Furthermore, we ectopically expressed EMP1 in human laryngeal carcinoma Hep-2 cells and examined the effects on cell viability, apoptosis, colonogenicity, and motility, by MTT assay, flow cytometry, colony formation assay and Transwell migration assay, respectively. EMP1 expression (on both the mRNA and protein levels) was significantly lower in the cancer tissues than in matched peritumor tissues (P<0.05). In laryngeal cancers, the level of EMP1 protein was correlated with histological grade (P<0.05), but not with age, gender, clinical stage, cancer subtype or lymph node metastasis (P>0.05). Functionally, ectopic expression of EMP1 in Hep-2 cells significantly reduced cell viability, colony formation, and migration, but enhanced apoptosis. Therefore, EMP1 is a tumor suppressor in laryngeal carcinoma. Boosting EMP1 expression in laryngeal carcinoma initiates multiple anticancer phenotypes and thus presents a promising therapeutic strategy for laryngeal cancer.

Novel interactions between erythroblast macrophage protein and cell migration.

PubMed

Javan, Gulnaz T; Can, Ismail; Yeboah, Fred; Lee, Youngil; Soni, Shivani

2016-09-01

Erythroblast macrophage protein is a novel protein known to mediate attachment of erythroid cells to macrophages to form erythroblastic islands in bone marrow during erythropoiesis. Emp-null macrophages are small with round morphologies, and lack cytoplasmic projections which imply immature structure. The role of Emp in macrophage development and function is not fully elucidated. Macrophages perform varied functions (e.g. homeostasis, erythropoiesis), and are implicated in numerous pathophysiological conditions such as cellular malignancy. The objective of the current study is to investigate the interaction of Emp with cytoskeletal- and cell migration-associated proteins involved in macrophage functions. A short hairpin RNA lentiviral system was use to down-regulate the expression of Emp in macrophage cells. A cell migration assay revealed that the relocation of macrophages was significantly inhibited when Emp expression was decreased. To further analyze changes in gene expression related to cell motility, PCR array was performed by down-regulating Emp expression. The results indicated that expression of mitogen-activated protein kinase 1 and thymoma viral proto-oncogene 1 were significantly higher when Emp was down-regulated. The results implicate Emp in abnormal cell motility, thus, warrants to assess its role in cancer where tumor cell motility is required for invasion and metastasis. Copyright © 2016 Elsevier Inc. All rights reserved.

Erythroblast macrophage protein (Emp): Past, present, and future.

PubMed

Javan, Gulnaz T; Salhotra, Amandeep; Finley, Sheree J; Soni, Shivani

2018-01-01

This review is a journey of the landmark erythroblast macrophage protein (Emp) discovered in 1994, and it walks chronologically through the progress that has been made in understanding the biological function of this protein. Historically, Emp was the first identified cell attachment molecule and is expressed in both erythroblasts and macrophages and mediates their attachments to form erythroblastic islands. The absence of Emp erythroblasts shows defects in differentiation and enucleation. Emp-deficient macrophages display immature morphology characterized by small sizes, round shapes, and the lack of cytoplasmic projections. Although the primary sequence of Emp has already been determined and its role in both erythroid and macrophage development is well established, there are major gaps in the understanding of its function at the molecular level. Recent studies had implicated its importance in actin cytoskeleton remodeling and cell migration, but the molecular mechanisms are still enigmatic. Previous studies have also demonstrated that downregulation of Emp affects the expression of mitogen-associated protein kinase 1 (MAPK1) and thymoma viral protooncogene (AKT-1) resulting in abnormal cell motility. In this review, we summarize the proposed function of Emp based on previous studies, present scenarios, and its plausible future in translational research. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

AGE/RAGE-Induced EMP Release via the NOX-Derived ROS Pathway

PubMed Central

Chen, Ying-Hua; Chen, Zhang-Wei; Li, Hong-Mei

2018-01-01

Objective Diabetes is associated with accelerated formation of advanced glycation end products (AGEs) that are extensively found in circulating endothelial microparticles (EMPs). This study aimed to investigate whether AGEs have a direct effect on EMP formation and the possible underlying mechanism. Methods In vitro, cultured human umbilical vein endothelial cells (HUVECs) were incubated with AGEs (200 and 400 μg/ml) for 24 hours with or without pretreatment with anti-RAGE antibody, NOX inhibitor, or ROS scavenger. The number of CD31-positive EMPs was assessed by flow cytometry. Results The number of EMPs was significantly increased in HUVECs stimulated by AGEs in a dose-dependent manner. In addition, receptors for AGEs (RAGE), NAD(P)H oxidase (NOX), and reactive oxygen species (ROS) were increased by AGEs as compared to the control group. These changes could be reversed when HUVECs were pretreated with anti-RAGE antibody. Moreover, inhibition of NOX as well as antioxidant treatment reduced the release of EMPs induced by AGEs. Conclusion Our study suggested that AGEs increased EMP generation, which was mediated by RAGE signaling through NOX-derived ROS. PMID:29744367

AGE/RAGE-Induced EMP Release via the NOX-Derived ROS Pathway.

PubMed

Chen, Ying-Hua; Chen, Zhang-Wei; Li, Hong-Mei; Yan, Xin-Feng; Feng, Bo

2018-01-01

Diabetes is associated with accelerated formation of advanced glycation end products (AGEs) that are extensively found in circulating endothelial microparticles (EMPs). This study aimed to investigate whether AGEs have a direct effect on EMP formation and the possible underlying mechanism. In vitro, cultured human umbilical vein endothelial cells (HUVECs) were incubated with AGEs (200 and 400  μ g/ml) for 24 hours with or without pretreatment with anti-RAGE antibody, NOX inhibitor, or ROS scavenger. The number of CD31-positive EMPs was assessed by flow cytometry. The number of EMPs was significantly increased in HUVECs stimulated by AGEs in a dose-dependent manner. In addition, receptors for AGEs (RAGE), NAD(P)H oxidase (NOX), and reactive oxygen species (ROS) were increased by AGEs as compared to the control group. These changes could be reversed when HUVECs were pretreated with anti-RAGE antibody. Moreover, inhibition of NOX as well as antioxidant treatment reduced the release of EMPs induced by AGEs. Our study suggested that AGEs increased EMP generation, which was mediated by RAGE signaling through NOX-derived ROS.

Investigating lightning-to-ionosphere energy coupling based on VLF lightning propagation characterization

NASA Astrophysics Data System (ADS)

Lay, Erin Hoffmann

In this dissertation, the capabilities of the World-Wide Lightning Location Network (WWLLN) are analyzed in order to study the interactions of lightning energy with the lower ionosphere. WWLLN is the first global ground-based lightning location network and the first lightning detection network that continuously monitors lightning around the world in real time. For this reason, a better characterization of the WWLLN could allow many global atmospheric science problems to be addressed, including further investigation into the global electric circuit and global mapping of regions of the lower ionosphere likely to be impacted by strong lightning and transient luminous events. This dissertation characterizes the World-Wide Location Network (WWLLN) in terms of detection efficiency, location and timing accuracy, and lightning type. This investigation finds excellent timing and location accuracy for WWLLN. It provides the first experimentally-determined estimate of relative global detection efficiency that is used to normalize lightning counts based on location. These normalized global lightning data from the WWLLN are used to map intense storm regions around the world with high time and spatial resolution as well as to provide information on energetic emissions known as elves and terrestrial gamma-ray flashes (TGFs). This dissertation also improves WWLLN by developing a procedure to provide the first estimate of relative lightning stroke radiated energy in the 1-24 kHz frequency range by a global lightning detection network. These characterizations and improvements to WWLLN are motivated by the desire to use WWLLN data to address the problem of lightning-to-ionosphere energy coupling. Therefore, WWLLN stroke rates are used as input to a model, developed by Professor Mengu Cho at the Kyushu Institute of Technology in Japan, that describes the non-linear effect of lightning electromagnetic pulses (EMP) on the ionosphere by accumulating electron density changes resulting from the interaction of the EMP of ten successive lightning strokes with the lower ionosphere. Further studies must be completed to narrow uncertainties in the model, but the qualitative ionospheric response to successive EMPs is presented. Results from this study show that the non-linear effect of lightning EMP due to successive lightning strokes must be taken into account, and varies with altitude, such that the most significant electron density enhancement occurs at 88 km altitude.

Mapping the transcription start points of the Staphylococcus aureus eap, emp, and vwb promoters reveals a conserved octanucleotide sequence that is essential for expression of these genes.

PubMed

Harraghy, Niamh; Homerova, Dagmar; Herrmann, Mathias; Kormanec, Jan

2008-01-01

Mapping the transcription start points of the eap, emp, and vwb promoters revealed a conserved octanucleotide sequence (COS). Deleting this sequence abolished the expression of eap, emp, and vwb. However, electrophoretic mobility shift assays gave no evidence that this sequence was a binding site for SarA or SaeR, known regulators of eap and emp.

Extramedullary Solitary Plasmacytoma: Demonstrating the Role of 18F-FDG PET Imaging.

PubMed

Gautam, Archana; Sahu, Kamal Kant; Alamgir, Ahsan; Siddiqi, Imran; Ailawadhi, Sikander

2017-04-01

An Extramedullary Plasmacytoma (EMP) is characterized by a neoplastic proliferation of clonal plasma cells outside the medullary cavity. EMPs are a rare occurrence compared to other malignant plasma cell disorders and account for approximately 3-5% of plasma-cell neoplasms. Although most cases of EMP are not immediately life threatening at diagnosis, EMPs can progress to Multiple Myeloma (MM) and thus, warrant monitoring. Currently, there are no standard guidelines for when and how to monitor patients who are diagnosed with or treated for a solitary plasmacytoma. We present a case of solitary EMP who was treated adequately and definitively but developed a distinct, non-contiguous subsequent solitary EMP and was only discovered due to surveillance 18 F-Fludeoxyglucose Positron Emission Tomography ( 18 F-FDG) (PET) scan. Uniform surveillance guidelines should be developed and the potential benefits of PET and other imaging techniques as well as their cost should be considered.

Extramedullary Solitary Plasmacytoma: Demonstrating the Role of 18F-FDG PET Imaging

PubMed Central

Gautam, Archana; Sahu, Kamal Kant; Alamgir, Ahsan; Siddiqi, Imran

2017-01-01

An Extramedullary Plasmacytoma (EMP) is characterized by a neoplastic proliferation of clonal plasma cells outside the medullary cavity. EMPs are a rare occurrence compared to other malignant plasma cell disorders and account for approximately 3-5% of plasma-cell neoplasms. Although most cases of EMP are not immediately life threatening at diagnosis, EMPs can progress to Multiple Myeloma (MM) and thus, warrant monitoring. Currently, there are no standard guidelines for when and how to monitor patients who are diagnosed with or treated for a solitary plasmacytoma. We present a case of solitary EMP who was treated adequately and definitively but developed a distinct, non-contiguous subsequent solitary EMP and was only discovered due to surveillance 18F-Fludeoxyglucose Positron Emission Tomography (18F-FDG) (PET) scan. Uniform surveillance guidelines should be developed and the potential benefits of PET and other imaging techniques as well as their cost should be considered. PMID:28571247

Synthetic gelatinases inhibitor attenuates electromagnetic pulse-induced blood-brain barrier disruption by inhibiting gelatinases-mediated ZO-1 degradation in rats.

PubMed

Qiu, Lian-Bo; Zhou, Yan; Wang, Qi; Yang, Long-Long; Liu, Hai-Qiang; Xu, Sheng-Long; Qi, Yu-Hong; Ding, Gui-Rong; Guo, Guo-Zhen

2011-07-11

Previously we found that exposure to electromagnetic pulse (EMP) induced an increase in blood-brain-barrier (BBB) permeability and the degradation of tight junction protein ZO-1 in rats. Matrix metalloproteinases (MMPs), in particular gelatinases (MMP-2 and MMP-9), play a key role in degradation of tight junction proteins, are known mediators of BBB compromise. We hypothesized that the degradation of ZO-1 by gelatinases contributed to EMP-induced BBB opening. To test this hypothesis, the mRNA level of ZO-1, protein levels of MMP-2, MMP-9 and tissue inhibitor of metalloproteinases (TIMP-1 and TIMP-2) were detected in rat cerebral cortex after exposing rats to EMP at 200 kV/m for 200 pulses. It was found that the mRNA level of ZO-1 was unaltered at different time points after EMP exposure. The protein levels of MMP-2 and MMP-9 significantly increased at 3 h and 0.5 h, respectively. However, TIMP-1 (inhibitor of MMP-9) and TIMP-2 (inhibitor of MMP-2) only moderately increased after EMP exposure. In addition, in situ zymography results showed that the gelatinase activity increased in cerebral microvessels at 3 h after EMP exposure. When rats were treated with gelatinases inhibitor (SB-3CT) before EMP exposure, the EMP-induced BBB opening was attenuated and the ZO-1 degradation was reversed. Our results suggested that EMP-induced BBB opening was related to gelatinase mediated ZO-1 degradation. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

The Prognostic Value of Epithelial Membrane Protein 1 (EMP-1) in Patients with Laryngeal Carcinoma

PubMed Central

Liu, Chang; Wei, Xiaojun; Li, Feng; Wang, Li; Ruan, Xinjian; Jia, Jia; Zhang, Xia

2017-01-01

Background In the present study, we aimed to investigate the prognostic value of epithelial membrane protein 1 (EMP-1) gene in patients diagnosed with laryngeal carcinoma (LC). Material/Methods Patients who were pathologically diagnosed with LC were enrolled in the present study. The expression levels of EMP-1 in tumor tissues and corresponding normal tissues collected from the LC patients were detected by semi-reverse transcriptase polymerase chain reaction (semi-RT-PCR). Chi-square analysis was used to evaluate the relationship between EMP-1 expression level and clinical characteristics. Survival analysis for the study population was analyzed by Kaplan-Meier method with log rank test. Additionally, Cox regression model was applied to evaluate the prognostic value of EMP-1 in LC patients. Results 106 LC patients, including 55 men and 51 women, were enrolled in the present study. Semi-RT-PCR demonstrated that the expression level of EMP-1 was decreased in tumor tissues, compared with adjacent normal tissues (p<0.001). Moreover, the level was significantly associated with lymph node metastasis, histological grade, and clinical stage (p<0.05 for all). In addition, low levels of EMP-1 was significantly correlated with poor survival rate (log rank test, p=0.020). Cox regression analysis indicated that EMP-1 was an independent marker for LC prognosis (HR=2.755, 95% CI=1.123–6.760, p=0.027). Conclusions The abnormal expression of EMP-1 may be associated with progression of LC and the gene may act as a prognostic marker for LC. PMID:28779068

A mutational approach for the detection of genetic factors affecting seed size in maize.

PubMed

Sangiorgio, Stefano; Carabelli, Laura; Gabotti, Damiano; Manzotti, Priscilla Sofia; Persico, Martina; Consonni, Gabriella; Gavazzi, Giuseppe

2016-12-01

Genes influencing seed size. The designation emp (empty pericarp) refers to a group of defective kernel mutants that exhibit a drastic reduction in endosperm tissue production. They allow the isolation of genes controlling seed development and affecting seed size. Nine independently isolated emp mutants have been analyzed in this study and in all cases longitudinal sections of mature seeds revealed the absence of morphogenesis in the embryo proper, an observation that correlates with their failure to germinate. Complementation tests with the nine emp mutants, crossed inter se in all pairwise combinations, identified complementing and non-complementing pairs in the F 1 progenies. Data were then validated in the F 2 /F 3 generations. Mutant chromosomal location was also established. Overall our study has identified two novel emp genes and a novel allele at the previously identified emp4 gene. The introgression of single emp mutants in a different genetic background revealed the existence of a cryptic genetic variation (CGV) recognizable as a variable increase in the endosperm tissue. The unmasking of CGV by introducing single mutants in different genetic backgrounds is the result of the interaction of the emp mutants with a suppressor that has no obvious phenotype of its own and is present in the genetic background of the inbred lines into which the emp mutants were transferred. On the basis of these results, emp mutants could be used as tools for the detection of genetic factors that enhance the amount of endosperm tissue in the maize kernel and which could thus become valuable targets to exploit in future breeding programs.

Detrimental effect of electromagnetic pulse exposure on permeability of in vitro blood-brain-barrier model.

PubMed

Zhou, Jia Xing; Ding, Gui Rong; Zhang, Jie; Zhou, Yong Chun; Zhang, Yan Jun; Guo, Guo Zhen

2013-02-01

To study the effect of electromagnetic pulse (EMP) exposure on permeability of in vitro blood-brain-barrier (BBB) model. An in vitro BBB model, established by co-culturing brain microvascular endothelial cells (BMVEC) and astroglial cells (AC) isolated from rat brain, was exposed to EMP at 100 kV/m and 400 kV/m, respectively. Permeability of the model was assayed by measuring the transendothelial electrical resistance (TEER) and the horseradish peroxidase (HRP) transmission at different time points. Levels of BBB tight junction-related proteins were measured at 0, 1, 2, 4, 8, 12, 16, 20, 24 h after EMP exposure by Western blotting. The TEER level was lower in BBB model group than in control group at 12 h after EMP, exposure which returned to its normal level at 24 h. The 24 h recovery process was triphasic and biphasic respectively after EMP exposure at 100 kV/m and 400 kV/m. Following exposure to 400 kV/m EMP, the HRP permeability increased at 1-12 h and returned to its normal level at 24 h. Western blotting showed that the claudin-5 and ZO-1 protein levels were changed after EMP exposure. EMP exposure at 100 kV/m and 400 kV/m can increase the permeability of in vitro BBB model and BBB tight junction-related proteins such as ZO-1 and claudin-5 may change EMP-induced BBB permeability. Copyright © 2013 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

The Prognostic Value of Epithelial Membrane Protein 1 (EMP-1) in Patients with Laryngeal Carcinoma.

PubMed

Liu, Chang; Wei, Xiaojun; Li, Feng; Wang, Li; Ruan, Xinjian; Jia, Jia; Zhang, Xia

2017-08-05

BACKGROUND In the present study, we aimed to investigate the prognostic value of epithelial membrane protein 1 (EMP-1) gene in patients diagnosed with laryngeal carcinoma (LC). MATERIAL AND METHODS Patients who were pathologically diagnosed with LC were enrolled in the present study. The expression levels of EMP-1 in tumor tissues and corresponding normal tissues collected from the LC patients were detected by semi-reverse transcriptase polymerase chain reaction (semi-RT-PCR). Chi-square analysis was used to evaluate the relationship between EMP-1 expression level and clinical characteristics. Survival analysis for the study population was analyzed by Kaplan-Meier method with log rank test. Additionally, Cox regression model was applied to evaluate the prognostic value of EMP-1 in LC patients. RESULTS 106 LC patients, including 55 men and 51 women, were enrolled in the present study. Semi-RT-PCR demonstrated that the expression level of EMP-1 was decreased in tumor tissues, compared with adjacent normal tissues (p<0.001). Moreover, the level was significantly associated with lymph node metastasis, histological grade, and clinical stage (p<0.05 for all). In addition, low levels of EMP-1 was significantly correlated with poor survival rate (log rank test, p=0.020). Cox regression analysis indicated that EMP-1 was an independent marker for LC prognosis (HR=2.755, 95% CI=1.123-6.760, p=0.027). CONCLUSIONS The abnormal expression of EMP-1 may be associated with progression of LC and the gene may act as a prognostic marker for LC.

Efficacy of estramustine phosphate sodium hydrate (EMP) monotherapy in castration-resistant prostate cancer patients: report of 102 cases and review of literature.

PubMed

Matsumoto, Kazuhiro; Tanaka, Nobuyuki; Hayakawa, Nozomi; Ezaki, Taisuke; Suzuki, Kenjiro; Maeda, Takahiro; Ninomiya, Akiharu; Nakamura, So

2013-12-01

This retrospective chart review study was conducted to evaluate the efficacy of estramustine phosphate sodium hydrate (EMP) monotherapy in patients with castration-resistant prostate cancer (CRPC) and to determine who would benefit from EMP therapy. EMP was administered at a daily dose of 560 mg to 102 patients as a third-line therapy, who had already received combined androgen blockade (CAB) and subsequent alternative antiandrogen therapy. The responses to EMP after its induction and its toxicity were evaluated. We also analyzed the association between the clinicopathological factors of the patients and their responses to EMP therapy. A reduction in the serum prostate-specific antigen (PSA) 4 weeks after induction was observed in 70 patients (68.6%), while 30 cases (29.4%) achieved more than 50% reduction of PSA. Long-term reduction of PSA from baseline for more than 6 months was observed in 31 patients (30.4%). EMP treatment was discontinued in 11 patients (10.8%) because of side effects (nausea in six patients, gynecomastia in three patients, eruption in one patient, and liver dysfunction in one patient). Multivariate analysis demonstrated that long duration of prior hormonal therapy was an independent favorable factor for reduced PSA levels, long responses, and overall survival. The data suggest that oral EMP administration as a third-line monotherapy is well tolerated and effective to some degree in patients with CRPC who have already received CAB and subsequent alternative antiandrogen therapy. Thus, EMP can be regarded as one treatment option, especially for patients whose prior duration of hormonal therapy was long.

Catabolic Effects of Endothelial Cell-Derived Microparticles on Disc Cells: Implications in Intervertebral Disc Neovascularization and Degeneration

PubMed Central

Pohl, Pedro H. I.; Lozito, Thomas P.; Cuperman, Thais; Yurube, Takashi; Moon, Hong J.; Ngo, Kevin; Tuan, Rocky S.; Croix, Claudette St.; Sowa, Gwendolyn A.; Rodrigues, Luciano M. R.; Kang, James D.; Vo, Nam V.

2017-01-01

Neovascularization of intervertebral discs, a phenomenon considered pathological since normal discs are primarily avascular structures, occurs most frequently in annulus fibrosus (AF) of degenerated discs. Endothelial cells (ECs) are involved in this process, but the mechanism of the interaction between AF and endothelial cells is unclear. In this study we evaluated the effects on matrix catabolic activity of AF cells by the extracellular endothelial microparticles (EMPs) and soluble protein factors (SUP fraction) produced from ECs. Passage 1 human AF cells grown in monolayer cultures were treated for 72 hours with 250μg of EMPs or SUP fraction isolated from culture of the microvascular endothelial cell line, HEMC-I. Live-cell imaging revealed uptake of EMPs by AF cells. RT-PCR analysis demonstrated increased mRNA expression of MMP-1 (50.3 fold), MMP-3 (4.5 fold) and MMP-13 (5.5 fold) in AF cell cultures treated with EMPs compared to untreated control. Western analysis also demonstrated increased MMP protein expression in EMP-treated AF cells. AF cells treated with the SUP fraction also exhibited a dramatic increase in MMP mRNA and protein expression. Increased MMP expression is primarily due to EMP or SUP stimulation of AF cells since EMPs or SUP fraction alone contained negligible amount of MMPs. Interestingly, MMP activity was elevated in AF cell cultures treated with EMPs but not with SUP. This study revealed enhanced matrix catabolism as a molecular consequence of action of ECs on AF cells via EMPs, which might be expected during neo-angiogenesis of degenerating disc. PMID:27246627

77 FR 27178 - Notice of Funds Availability; Inviting Applications for the Emerging Markets Program; Correction

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-09

... for the Emerging Markets Program (EMP). The document contained incorrect dates. FOR FURTHER... Times. EMP funding is reviewed on a rolling basis during the fiscal year as long as EMP funding is...

Blockade of epithelial membrane protein 2 (EMP2) abrogates infection of Chlamydia muridarum murine genital infection model

PubMed Central

Shimazaki, Kaori; Chan, Ann M.; Moniz, Raymond J.; Wadehra, Madhuri; Nagy, Agnes; Coulam, C. Paige; Mareninov, Sergey; Lepin, Eric M.; Wu, Anna M.; Kelly, Kathleen A.; Braun, Jonathan; Gordon, Lynn K.

2012-01-01

New methods are needed to eradicate or prevent Chlamydia trachomatis infections. Blockade of epithelial membrane protein 2 (EMP2) by genetic silencing or neutralizing polyclonal antibody reduced chlamydial infectivity in vitro. This study tests the prediction that recombinant anti-EMP2 diabody could reduce early chlamydial infection of the genital tract in vivo. In a murine infection model, pretreatment with anti-EMP2 diabody, as compared to control diabody, significantly reduced bacterial load, tissue production of inflammatory cytokines, recruitment of polymorphonuclear leukocytes, and local tissue inflammation. These findings support EMP2 as a potential preventative and therapeutic target for genital chlamydial infection. PMID:19159428

A novel technique for producing antibody-coated microprobes using a thiol-terminal silane and a heterobifunctional crosslinker.

PubMed

Routh, V H; Helke, C J

1997-02-01

Antibody-coated microprobes are used to measure neuropeptide release in the central nervous system. Although they are not quantitative, they provide the most precise spatial resolution of the location of in vivo release of any currently available method. Previous methods of coating antibody microprobes are difficult and time-consuming. Moreover, using these methods we were unable to produce evenly coated antibody microprobes. This paper describes a novel method for the production of antibody microprobes using thiol-terminal silanes and the heterobifunctional crosslinker, 4-(4-N-maleimidophenyl)butyric acid hydrazide HCl 1/2 dioxane (MPBH). Following silation, glass micropipettes are incubated with antibody to substance P (SP) that has been conjugated to MPBH. This method results in a dense, even coating of antibody without decreasing the biological activity of the antibody. Additionally, this method takes considerably less time than previously described methods without sacrificing the use of antibody microprobes as micropipettes. The sensitivity of the microprobes for SP is in the picomolar range, and there is a linear correlation between the log of SP concentration (M) and B/B0 (r2 = 0.98). The microprobes are stable for up to 3 weeks when stored in 0.1 M sodium phosphate buffer with 50 mM NaCl (pH 7.4) at 5 degrees C. Finally, insertion into the exposed spinal cord of an anesthetized rat for 15 min produces no damage to the antibody coating.

Exponential Megapriming PCR (EMP) Cloning—Seamless DNA Insertion into Any Target Plasmid without Sequence Constraints

PubMed Central

Ulrich, Alexander; Andersen, Kasper R.; Schwartz, Thomas U.

2012-01-01

We present a fast, reliable and inexpensive restriction-free cloning method for seamless DNA insertion into any plasmid without sequence limitation. Exponential megapriming PCR (EMP) cloning requires two consecutive PCR steps and can be carried out in one day. We show that EMP cloning has a higher efficiency than restriction-free (RF) cloning, especially for long inserts above 2.5 kb. EMP further enables simultaneous cloning of multiple inserts. PMID:23300917

Exponential megapriming PCR (EMP) cloning--seamless DNA insertion into any target plasmid without sequence constraints.

PubMed

Ulrich, Alexander; Andersen, Kasper R; Schwartz, Thomas U

2012-01-01

We present a fast, reliable and inexpensive restriction-free cloning method for seamless DNA insertion into any plasmid without sequence limitation. Exponential megapriming PCR (EMP) cloning requires two consecutive PCR steps and can be carried out in one day. We show that EMP cloning has a higher efficiency than restriction-free (RF) cloning, especially for long inserts above 2.5 kb. EMP further enables simultaneous cloning of multiple inserts.

A research program to assess the impact of the electromagnetic pulse on electric power systems

NASA Astrophysics Data System (ADS)

McConnell, B. W.; Barnes, P. R.

A strong electromagnetic pulse (EMP) with an electric-field component on the order of tens of kilovolts per meter is produced by a nuclear detonation in or above the atmosphere. This paper presents an overview and a summary of the results to date of a program formulated to address the research and development of technologies and systems required to assess and reduce the impact of EMP on electric power systems. The technologies and systems being considered include simulation models, methods of assessment, definition of required experiments and data, development of protective hardware, and the creation or revision of operating and control procedures. Results to date include the development of relatively simple unclassified EMP environment models, the development of methods for extending EMP coupling models to the large transmission and distribution network associated with the electric power system, and the performance of a parametric study of HEMP induced surges using an appropriate EMP environment. An experiment to investigate the effect of corona on the coupling of EMP to conductors has been defined and has been performed in an EMP simulator. Experiments to determine the response of key components to simulated EMP surges and an investigation of the impact of steep-front, short-duration impulse on a selected number of the insulation systems used in electric power systems apparatus are being performed.

Interferon-β1a reduces plasma CD31+ endothelial microparticles (CD31+EMP) in multiple sclerosis

PubMed Central

Sheremata, William A; Jy, Wenche; Delgado, Sylvia; Minagar, Alireza; McLarty, Jerry; Ahn, Yeon

2006-01-01

Background A correlation between plasma CD31+ endothelial microparticles (CD31+EMP) levels and clinical, as well as brain MRI activity, in multiple sclerosis (MS) patients has been previously reported. However, the effect(s) of treatment with interferon-β1a (IFN-β1a) on plasma levels of CD31+EMP has not been assessed. In a prospective study, we measured plasma CD31+EMP levels in 30 patients with relapsing-remitting MS. Methods Using flow cytometry, in a blinded study, we measured plasma CD31+EMP in 30 consecutive patients with relapsing-remitting MS (RRMS) prior to and 4, 12, 24 and 52 weeks after initiation of intramuscular therapy with interferon-β1a (IFN-β1a), 30 micrograms weekly. At each visit, clinical examination was performed and expanded disability status scale (EDSS) scores were assessed. Results Plasma levels of CD31+EMP were significantly reduced from 24 through 52 weeks following initiation of treatment with IFN-β1a. Conclusion Our data suggest that serial measurement of plasma CD31+EMP levels may be used as a surrogate marker of response to therapy with INF-β1a. In addition, the decline in plasma levels of CD31+EMP further supports the concept that IFN-β1a exerts stabilizing effect on the cerebral endothelial cells in pathogenesis of MS. PMID:16952316

Interferon-beta1a reduces plasma CD31+ endothelial microparticles (CD31+EMP) in multiple sclerosis.

PubMed

Sheremata, William A; Jy, Wenche; Delgado, Sylvia; Minagar, Alireza; McLarty, Jerry; Ahn, Yeon

2006-09-04

A correlation between plasma CD31+ endothelial microparticles (CD31+EMP) levels and clinical, as well as brain MRI activity, in multiple sclerosis (MS) patients has been previously reported. However, the effect(s) of treatment with interferon-beta1a (IFN-beta1a) on plasma levels of CD31+EMP has not been assessed. In a prospective study, we measured plasma CD31+EMP levels in 30 patients with relapsing-remitting MS. Using flow cytometry, in a blinded study, we measured plasma CD31+EMP in 30 consecutive patients with relapsing-remitting MS (RRMS) prior to and 4, 12, 24 and 52 weeks after initiation of intramuscular therapy with interferon-beta1a (IFN-beta1a), 30 micrograms weekly. At each visit, clinical examination was performed and expanded disability status scale (EDSS) scores were assessed. Plasma levels of CD31+EMP were significantly reduced from 24 through 52 weeks following initiation of treatment with IFN-beta1a. Our data suggest that serial measurement of plasma CD31+EMP levels may be used as a surrogate marker of response to therapy with INF-beta1a. In addition, the decline in plasma levels of CD31+EMP further supports the concept that IFN-beta1a exerts stabilizing effect on the cerebral endothelial cells in pathogenesis of MS.

Clinical analysis of 40 multiple myeloma patients with extramedullary plasmacytoma of the head.

PubMed

Sun, Wan-Jun; Zhang, Jia-Jia; An, Na; Shen, Men; Huang, Zhong-Xia; Li, Xin

2016-12-01

Objectives To investigate the clinical characteristics, survival and prognosis of patients with multiple myeloma (MM) and head extramedullary plasmacytoma (EMP). Methods Forty MM patients were enrolled in the study (18 men, 22 women; median age, 55 years). Results Median overall survival (OS) and progression-free survival (PFS) were 24 (5-78) months and 17 (2-36) months, respectively. The 2-, 3- and 5-year OS rates were 51%, 20% and 7%, respectively. The 2-year PFS was 15%. Median OS and PFS in patients administered velcade were 26 (18-50) and 22.5 (5-78) months, compared with 20 (10-30) and 13.5 (2-36) months in patients without velcade, respectively. Median OS was 23.5 (5-50) months in patients with EMP at MM diagnosis ( n = 25) and 36 (22-78) months in patients with head EMP diagnosed during the disease course ( n = 15). Sixteen MM patients had EMP invasion of the head only and 24 had invasion at multiple sites. Median OS was 25 (22-78) months in patients with EMP of the head only and 22 (5-78) months in patients with EMP invasion at multiple sites. Conclusion MM patients with head EMP show a more aggressive disease course and shorter OS and PFS. The prognosis of these patients is poor, especially in patients with head EMP at MM diagnosis, though combined chemotherapy and radiotherapy may prolong survival.

A comparative study of modern and fossil cone scales and seeds of conifers: A geochemical approach

USGS Publications Warehouse

Artur, Stankiewicz B.; Mastalerz, Maria; Kruge, M.A.; Van Bergen, P. F.; Sadowska, A.

1997-01-01

Modern cone scales and seeds of Pinus strobus and Sequoia sempervirens, and their fossil (Upper Miocene, c. 6 Mar) counterparts Pinus leitzii and Sequoia langsdorfi have been studied using pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), electron-microprobe and scanning electron microscopy. Microscopic observations revealed only minor microbial activity and high-quality structural preservation of the fossil material. The pyrolysates of both modern genera showed the presence of ligno-cellulose characteristic of conifers. However, the abundance of (alkylated)phenols and 1,2-benzenediols in modern S. sempervirens suggests the presence of non-hydrolysable tannins or abundant polyphenolic moieties not previously reported in modern conifers. The marked differences between the pyrolysis products of both modern genera are suggested to be of chemosystematic significance. The fossil samples also contained ligno-cellulose which exhibited only partial degradation, primarily of the carbohydrate constituents. Comparison between the fossil cone scale and seed pyrolysates indicated that the ligno-cellulose complex present in the seeds is chemically more resistant than that in the cone scales. Principal component analysis (PCA) of the pyrolysis data allowed for the determination of the discriminant functions used to assess the extent of degradation and the chemosystematic differences between both genera and between cone scales and seeds. Elemental composition (C, O, S), obtained using electron-microprobe, corroborated the pyrolysis results. Overall, the combination of chemical, microscopic and statistical methods allowed for a detailed characterization and chemosystematic interpretations of modern and fossil conifer cone scales and seeds.

The matrices of unequilibrated ordinary chondrites - Implications for the origin and history of chondrites

NASA Technical Reports Server (NTRS)

Huss, G. R.; Keil, K.; Taylor, G. J.

1981-01-01

The matrices of 16 unequilibrated chondrites were examined by optical microscopy, an electron microprobe, and a scanning electron microscope. The fine-grained, opaque, silicate matrix of type 3 unequilibrated chondrites was compositionally, mineralogically, and texturally different from the chondrules and their fragments; it may be the low temperature condensate proposed by Larimer and Anders (1967, 1970). Each meteorite has been metamorphosed by a combination of processes including thermal metamorphism and the passage of shock waves; the appearance of each chondrite results from the temperature and pressure conditions which formed it, and subsequent metamorphic alterations.

Oxidation of silicon nitride sintered with rare-earth oxide additions

NASA Technical Reports Server (NTRS)

Mieskowski, D. M.; Sanders, W. A.

1985-01-01

The effects of rare-earth oxide additions on the oxidation of sintered Si3N4 were examined. Insignificant oxidation occurred at 700 and 1000 C, with no evidence of phase instability. At 1370 C, the oxidation rate was lowest for Y2O3 and increased for additions of La2O3, Sm2O3, and CeO2, in that order. Data obtained from X-ray diffraction, electron microprobe analysis, and scanning electron microscopy indicate that oxidation occurs via diffusion of cationic species from Si3N4 grain boundaries.

The detection of sulphur in contamination spots in electron probe X-ray microanalysis

USGS Publications Warehouse

Adler, I.; Dwornik, E.J.; Rose, H.J.

1962-01-01

Sulphur has been identified as one of the elements present in the contamination spot which forms under the electron beam in the microprobe. The presence of the sulphur results in a rapid change in intensity measurements causing a loss of observed intensity for elements other than sulphur. The source of sulphur has been traced at least in part to the Apiezon B diffusion pump oil. A comparative X-ray fluorescence study of the Apiezon B and Octoil diffusion pump oils showed substantial amounts of sulphur in the Apiezon B. The Octoil was relatively free of sulphur.

Determination of niobium in rocks, ores and alloys by atomic-absorption spectrophotometry.

PubMed

Husler, J

1972-07-01

Niobium, in concentrations as low as 0.02% Nb(2)O(5), is determined in a variety of materials without separation or enrichment. Chemical and ionization interferences are controlled, and sensitivity is increased, by maintaining the iron, aluminium, hydrofluoric acid and potassium content within certain broad concentration limits. There is close agreement with the results of analyses by emission spectrographic, electron microprobe and X-ray fluorescence methods.

Effect of chromium and phosphorus on the physical properties of iron and titanium-based amorphous metallic alloy films

NASA Technical Reports Server (NTRS)

Distefano, S.; Rameshan, R.; Fitzgerald, D. J.

1991-01-01

Amorphous iron and titanium-based alloys containing various amounts of chromium, phosphorus, and boron exhibit high corrosion resistance. Some physical properties of Fe and Ti-based metallic alloy films deposited on a glass substrate by a dc-magnetron sputtering technique are reported. The films were characterized using differential scanning calorimetry, stress analysis, SEM, XRD, SIMS, electron microprobe, and potentiodynamic polarization techniques.

Investigation of gold embrittlement in connector solder joints

NASA Technical Reports Server (NTRS)

Lane, F. L.

1972-01-01

An investigation was performed to determine to what extent typical flight connector solder joints may be embrittled by the presence of gold. In addition to mapping of gold content in connector solder joints by an electron microprobe analyzer, metallographic examinations and mechanical tests (thermal shock, vibration, impact and tensile strength) were also conducted. A description of the specimens and tests, a discussion of the data, and some conclusions are presented.

Effect of endothelin-1 and endothelin receptor blockade on the release of microparticles.

PubMed

Jung, Christian; Lichtenauer, Michael; Wernly, Bernhard; Franz, Marcus; Goebel, Bjoern; Rafnsson, Arnar; Figulla, Hans-Reiner; Pernow, John

2016-08-01

Increased levels of endothelial cell microparticles (EMP) are known to reflect endothelial dysfunction (ED). In diabetes mellitus type 2 (T2DM), the expression of endothelin (ET)-1 is increased. As treatment with an ET-1 antagonist significantly inhibited atherosclerosis in animal models, we sought to investigate whether treatment with ET-1 antagonists affects EMP levels in vitro and in vivo in patients with T2DM. In vitro study: Human umbilical vein endothelial cells (HUVEC) were stimulated with ET-1 alone and ET-1 in combination with a dual ET-A and ET-B endothelin receptor blocker. In vivo study: Patients with T2DM were randomized to treatment with the ET receptor antagonist bosentan or placebo. After 4 weeks, the patients were re-examined and blood samples were obtained. EMP counts in supernatants and plasma samples were determined using flow cytometry. In vitro study: In supernatants of ET-1-stimulated HUVECs, the increased release of EMP was reduced significantly by co-incubation with an ET-1 receptor antagonist (e.g. CD31+/CD42b-EMP decreased from 37·1% ± 2·8 to 31·5% ± 2·8 SEM, P = 0·0078). In vivo study: No changes in EMP levels in blood samples of patients with T2DM were found after 4 weeks of bosentan treatment (n = 36, P = ns). Our in vitro results suggest that ET-1 stimulates the release of EMP from HUVECs via a receptor-dependent mechanism. Co-incubation with an endothelin receptor blocker abolished ET-1-dependent EMP release. However, treatment with bosentan for 4 weeks failed to alter EMP levels in patients with T2DM. Other factors seem to have influenced EMP release in patients with T2DM independent of ET-1 receptor-mediated mechanisms. © 2016 Stichting European Society for Clinical Investigation Journal Foundation.

Analysis of gene expression profile induced by EMP-1 in esophageal cancer cells using cDNA Microarray

PubMed Central

Wang, Hai-Tao; Kong, Jian-Ping; Ding, Fang; Wang, Xiu-Qin; Wang, Ming-Rong; Liu, Lian-Xin; Wu, Min; Liu, Zhi-Hua

2003-01-01

AIM: To obtain human esophageal cancer cell EC9706 stably expressed epithelial membrane protein-1 (EMP-1) with integrated eukaryotic plasmid harboring the open reading frame (ORF) of human EMP-1, and then to study the mechanism by which EMP-1 exerts its diverse cellular action on cell proliferation and altered gene profile by exploring the effect of EMP-1. METHODS: The authors first constructed pcDNA3.1/myc-his expression vector harboring the ORF of EMP-1 and then transfected it into human esophageal carcinoma cell line EC9706. The positive clones were analyzed by Western blot and RT-PCR. Moreover, the cell growth curve was observed and the cell cycle was checked by FACS technique. Using cDNA microarray technology, the authors compared the gene expression pattern in positive clones with control. To confirm the gene expression profile, semi-quantitative RT-PCR was carried out for 4 of the randomly picked differentially expressed genes. For those differentially expressed genes, classification was performed according to their function and cellular component. RESULTS: Human EMP-1 gene can be stably expressed in EC9706 cell line transfected with human EMP-1. The authors found the cell growth decreased, among which S phase was arrested and G1 phase was prolonged in the transfected positive clones. By cDNA microarray analysis, 35 genes showed an over 2.0 fold change in expression level after transfection, with 28 genes being consistently up-regulated and 7 genes being down-regulated. Among the classified genes, almost half of the induced genes (13 out of 28 genes) were related to cell signaling, cell communication and particularly to adhesion. CONCLUSION: Overexpression of human EMP-1 gene can inhibit the proliferation of EC9706 cell with S phase arrested and G1 phase prolonged. The cDNA microarray analysis suggested that EMP-1 may be one of regulators involved in cell signaling, cell communication and adhesion regulators. PMID:12632483

Analysis of gene expression profile induced by EMP-1 in esophageal cancer cells using cDNA Microarray.

PubMed

Wang, Hai-Tao; Kong, Jian-Ping; Ding, Fang; Wang, Xiu-Qin; Wang, Ming-Rong; Liu, Lian-Xin; Wu, Min; Liu, Zhi-Hua

2003-03-01

To obtain human esophageal cancer cell EC9706 stably expressed epithelial membrane protein-1 (EMP-1) with integrated eukaryotic plasmid harboring the open reading frame (ORF) of human EMP-1, and then to study the mechanism by which EMP-1 exerts its diverse cellular action on cell proliferation and altered gene profile by exploring the effect of EMP-1. The authors first constructed pcDNA3.1/myc-his expression vector harboring the ORF of EMP-1 and then transfected it into human esophageal carcinoma cell line EC9706. The positive clones were analyzed by Western blot and RT-PCR. Moreover, the cell growth curve was observed and the cell cycle was checked by FACS technique. Using cDNA microarray technology, the authors compared the gene expression pattern in positive clones with control. To confirm the gene expression profile, semi-quantitative RT-PCR was carried out for 4 of the randomly picked differentially expressed genes. For those differentially expressed genes, classification was performed according to their function and cellular component. Human EMP-1 gene can be stably expressed in EC9706 cell line transfected with human EMP-1. The authors found the cell growth decreased, among which S phase was arrested and G1 phase was prolonged in the transfected positive clones. By cDNA microarray analysis, 35 genes showed an over 2.0 fold change in expression level after transfection, with 28 genes being consistently up-regulated and 7 genes being down-regulated. Among the classified genes, almost half of the induced genes (13 out of 28 genes) were related to cell signaling, cell communication and particularly to adhesion. Overexpression of human EMP-1 gene can inhibit the proliferation of EC9706 cell with S phase arrested and G1 phase prolonged. The cDNA microarray analysis suggested that EMP-1 may be one of regulators involved in cell signaling, cell communication and adhesion regulators.

EMP-1 is a junctional protein in a liver stem cell line and in the liver.

PubMed

Lee, Hsuan-Shu; Sherley, James L; Chen, Jeremy J W; Chiu, Chien-Chang; Chiou, Ling-Ling; Liang, Ja-Der; Yang, Pan-Chyr; Huang, Guan-Tarn; Sheu, Jin-Chuan

2005-09-09

In an attempt to discover cell markers for liver stem cells, a cDNA microarray analysis was carried out to compare the gene expression profiles between an adult liver stem cell line, Lig-8, and mature hepatocytes. Several genes in the categories of extracellular matrix, cell membrane, cell adhesion, transcription factor, signal molecule, transporter, and metabolic enzyme were shown to be differentially expressed in Lig-8 cells. Among them, epithelial membrane protein (EMP)-1 has been previously implicated with stem cell phenotypes. Antiserum to EMP-1 was produced to localize its expression. On monolayers of Lig-8 cells, EMP-1 was expressed along the intercellular border. In the liver harboring proliferating oval cells, the liver progenitors, EMP-1 was localized as ribbon bands, a staining pattern for epithelial junctions, all the way through bile duct epithelia, oval cell ductules, and into peri-hepatocytic regions. These peri-hepatocytic regions were proved to be bile canaliculi by co-localization of EMP-1 and dipeptidyl peptidase IV, an enzyme located on bile canaliculi. This report is the first to indicate EMP-1 to be a junctional protein in the liver.

Endothelial microparticles: Pathogenic or passive players in endothelial dysfunction in autoimmune rheumatic diseases?

PubMed

McCarthy, E M; Wilkinson, F L; Parker, B; Alexander, M Y

2016-11-01

Autoimmune rheumatic diseases are characterised by systemic inflammation and complex immunopathology, with an increased risk of cardiovascular disease, initiated by endothelial dysfunction in a chronic inflammatory environment. Endothelial microparticles (EMPs) are released into the circulation from activated endothelial cells and may therefore, reflect disease severity, vascular and endothelial dysfunction, that could influence disease pathogenesis via autocrine/paracrine signalling. The exact function of EMPs in rheumatic disease remains unknown, and this has initiated research to elucidate EMP composition and function, which may be determined by the mode of endothelial activation and the micro environment. To date, EMPs are thought to play a role in angiogenesis, thrombosis and inflammation by transferring specific proteins and microRNAs (miRs) to target cells. Here, we review the mechanisms underlying the generation and composition of EMPs and the clinical and experimental studies describing the involvement of EMPs in rheumatic diseases, since we have previously shown endothelial dysfunction and an elevated risk of cardiovascular disease are characteristics in systemic lupus erythematosus. We will also discuss the potential of EMPs as future biomarkers of cardiovascular risk in these diseases. Copyright © 2016 Elsevier Inc. All rights reserved.

F14A System Safety Program Plan

DTIC Science & Technology

1981-09-03

by block number) Electromagnetic Pulse (EMP) Safety Plans Test Program EMP Testing F14 Aircraft Plans 20 ABSTRACT (Continue on reverse side if...compromising completion of the required experimental tasks. This document addresses the safety aspect of performing an Electromagnetic Pulse (EMP) test

Electromagnetic Pulse (EMP) Survivability of Telecommunications Assets

DTIC Science & Technology

1987-02-06

Program Approach ES-2 2-1 EMP Mitigation Program Approach 2-2 2-2 Approach To The Assessment Of EMP Effects On Networks 2-3 2-3 Zone-Boundary Model 2-5...2-4 Approach To The Assessment Of EMP Effects On Networks 2-6 4-1 Zone-Boundary Model And Communications Network Elements 4-1 4-2 Important Features...data and theoretical analyses to arrive at the conclusions presented in this report. TMTrademark of Western Electric Co., Inc. ES-4 - i S

Dose dependency of outcomes of intrapleural fibrinolytic therapy in new rabbit empyema models

PubMed Central

Florova, Galina; Azghani, Ali O.; Buchanan, Ann; Boren, Jake; Allen, Timothy; Rahman, Najib M.; Koenig, Kathleen; Chamiso, Mignote; Karandashova, Sophia; Henry, James; Idell, Steven

2016-01-01

The incidence of empyema (EMP) is increasing worldwide; EMP generally occurs with pleural loculation and impaired drainage is often treated with intrapleural fibrinolytic therapy (IPFT) or surgery. A number of IPFT options are used clinically with empiric dosing and variable outcomes in adults. To evaluate mechanisms governing intrapleural fibrinolysis and disease outcomes, models of Pasteurella multocida and Streptococcus pneumoniae were generated in rabbits and the animals were treated with either human tissue (tPA) plasminogen activator or prourokinase (scuPA). Rabbit EMP was characterized by the development of pleural adhesions detectable by chest ultrasonography and fibrinous coating of the pleura. Similar to human EMP, rabbits with EMP accumulated sizable, 20- to 40-ml fibrinopurulent pleural effusions associated with extensive intrapleural organization, significantly increased pleural thickness, suppression of fibrinolytic and plasminogen-activating activities, and accumulation of high levels of plasminogen activator inhibitor 1, plasminogen, and extracellular DNA. IPFT with tPA (0.145 mg/kg) or scuPA (0.5 mg/kg) was ineffective in rabbit EMP (n = 9 and 3 for P. multocida and S. pneumoniae, respectively); 2 mg/kg tPA or scuPA IPFT (n = 5) effectively cleared S. pneumoniae-induced EMP collections in 24 h with no bleeding observed. Although intrapleural fibrinolytic activity for up to 40 min after IPFT was similar for effective and ineffective doses of fibrinolysin, it was lower for tPA than for scuPA treatments. These results demonstrate similarities between rabbit and human EMP, the importance of pleural fluid PAI-1 activity, and levels of plasminogen in the regulation of intrapleural fibrinolysis and illustrate the dose dependency of IPFT outcomes in EMP. PMID:27343192

MHD-EMP protection guidelines

NASA Astrophysics Data System (ADS)

Barnes, P. R.; Vance, E. F.

A nuclear detonation at altitudes several hundred kilometers above the earth will severely distort the earth's magnetic field and result in a strong magnetohydrodynamic electromagnetic pulse (MHD-EMP). The geomagnetic disturbance interacts with the soil to induce current and horizontal electric gradients. MHD-EMP, also called E3 since it is the third component of the high-altitude EMP (HEMP), lasts over 100 s after an exoatmospheric burst. MHD-EMP is similar to solar geomagnetic storms in it's global and low frequency (less than 1 Hz) nature except that E3 can be much more intense with a far shorter duration. When the MHD-EMP gradients are integrated over great distances by power lines, communication cables, or other long conductors, the induced voltages are significant. (The horizontal gradients in the soil are too small to induce major responses by local interactions with facilities.) The long pulse waveform for MHD-EMP-induced currents on long lines has a peak current of 200 A and a time-to-half-peak of 100 s. If this current flows through transformer windings, it can saturate the magnetic circuit and cause 60 Hz harmonic production. To mitigate the effects of MHD-EMP on a facility, long conductors must be isolated from the building and the commercial power harmonics and voltage swings must be addressed. The transfer switch would be expected to respond to the voltage fluctuations as long as the harmonics have not interfered with the switch control circuitry. The major sources of MHD-EMP induced currents are the commercial power lines and neutral; neutral current indirect coupling to the facility power or ground system via the metal fence, powered gate, parking lights, etc; metal water pipes; phone lines; and other long conductors that enter or come near the facility. The major source of harmonics is the commercial power system.

Endothelial microparticles interact with and support the proliferation of T cells.

PubMed

Wheway, Julie; Latham, Sharissa L; Combes, Valery; Grau, Georges E R

2014-10-01

Endothelial cells closely interact with circulating lymphocytes. Aggression or activation of the endothelium leads to an increased shedding of endothelial cell microparticles (MP). Endothelial MP (EMP) are found in high plasma levels in numerous immunoinflammatory diseases, such as atherosclerosis, sepsis, multiple sclerosis, and cerebral malaria, supporting their role as effectors and markers of vascular dysfunction. Given our recently described role for human brain microvascular endothelial cells (HBEC) in modulating immune responses, we investigated how HBEC-derived MP could interact with and support the proliferation of T cells. Like their mother cells, EMP expressed molecules important for Ag presentation and T cell costimulation, that is, β2-microglobulin, MHC II, CD40, and ICOSL. HBEC were able to take up fluorescently labeled Ags with EMP also containing fluorescent Ags, suggestive of Ag carryover from HBEC to EMP. In cocultures, fluorescently labeled EMP from resting or cytokine-stimulated HBEC formed conjugates with both CD4(+) and CD8(+) subsets, with higher proportions of T cells binding EMP from cytokine-stimulated cells. The increased binding of EMP from cytokinestimulated HBEC to T cells was VCAM-1 and ICAM-1 dependent. Finally, in CFSE T cell proliferation assays using anti-CD3 mAb or T cell mitogens, EMP promoted the proliferation of CD4(+) T cells and that of CD8(+) T cells in the absence of exogenous stimuli and in the T cell mitogenic stimulation. Our findings provide novel evidence that EMP can enhance T cell activation and potentially ensuing Ag presentation, thereby pointing toward a novel role for MP in neuroimmunological complications of infectious diseases. Copyright © 2014 by The American Association of Immunologists, Inc.

Shear stress regulates endothelial microparticle release.

PubMed

Vion, Anne-Clémence; Ramkhelawon, Bhama; Loyer, Xavier; Chironi, Gilles; Devue, Cecile; Loirand, Gervaise; Tedgui, Alain; Lehoux, Stéphanie; Boulanger, Chantal M

2013-05-10

Endothelial activation and apoptosis release membrane-shed microparticles (EMP) that emerge as important biological effectors. Because laminar shear stress (SS) is a major physiological regulator of endothelial survival, we tested the hypothesis that SS regulates EMP release. EMP levels were quantified by flow cytometry in medium of endothelial cells subjected to low or high SS (2 and 20 dyne/cm(2)). EMP levels augmented with time in low SS conditions compared with high SS conditions. This effect was sensitive to extracellular signal-regulated protein kinases 1 and 2 (ERK1/2) and Rho kinases inhibitors but unaffected by caspase inhibitors. Low SS-stimulated EMP release was associated with increased endothelial Rho kinases and ERK1/2 activities and cytoskeletal reorganization. Overexpression of constitutively active RhoA stimulated EMP release under high SS. We also examined the effect of nitric oxide (NO) in mediating SS effects. L-NG-nitroarginine methyl ester (L-NAME), but not D-NG-nitroarginine methyl ester, increased high SS-induced EMP levels by 3-fold, whereas the NO donor S-nitroso-N-acetyl-D,L-penicillamine (SNAP) decreased it. L-NAME and SNAP did not affect Rho kinases and ERK1/2 activities. Then, we investigated NO effect on membrane remodeling because microparticle release is abolished in ABCA1-deficient cells. ABCA1 expression, which was greater under low SS than under high SS, was augmented by L-NAME under high SS and decreased by SNAP under low SS conditions. Altogether, these results demonstrate that sustained atheroprone low SS stimulates EMP release through activation of Rho kinases and ERK1/2 pathways, whereas atheroprotective high SS limits EMP release in a NO-dependent regulation of ABCA1 expression and of cytoskeletal reorganization. These findings, therefore, identify endothelial SS as a physiological regulator of microparticle release.

Endothelial microparticles interact with and support the proliferation of T cells

PubMed Central

Wheway, Julie; Latham, Sharissa L; Combes, Valery; Grau, Georges ER

2014-01-01

Endothelial cells (EC) closely interact with circulating lymphocytes. Aggression or activation of the endothelium leads to an increased shedding of EC microparticles (MP). Endothelial MP (EMP) are found in high plasma levels in numerous immunoinflammatory diseases, e.g. atherosclerosis, sepsis, multiple sclerosis and cerebral malaria, supporting their role as effectors and markers of vascular dysfunction. Given our recently described role for human brain microvascular endothelial cells (HBEC) in modulating immune responses we investigated how HBEC-derived MP could interact with and support the proliferation of T cells. Like their mother cells, EMP expressed molecules important for antigen presentation and T cell co-stimulation, i.e., β2-microglobulin, MHC II, CD40 and ICOSL. HBEC were able to take up fluorescently labeled antigens with EMP also containing fluorescent antigens suggestive of antigen carryover from HBEC to EMP. In co-cultures, fluorescently labeled EMP from resting or cytokine-stimulated HBEC formed conjugates with both CD4+ and CD8+ subsets, with higher proportions of T cells binding EMP from cytokine stimulated cells. The increased binding of EMP from cytokine stimulated HBEC to T cells was VCAM-1 and ICAM-1-dependent. Finally, in CFSE T cell proliferation assays using anti-CD3 mAb or T cell mitogens, EMP promoted the proliferation of CD4+ T cells and that of CD8+ T cells in the absence of exogenous stimuli and in the T cell mitogenic stimulation. Our findings provide novel evidence that EMP can enhance T cell activation and potentially ensuing antigen presentation, thereby pointing towards a novel role for MP in neuro-immunological complications of infectious diseases. PMID:25187656

Dose dependency of outcomes of intrapleural fibrinolytic therapy in new rabbit empyema models.

PubMed

Komissarov, Andrey A; Florova, Galina; Azghani, Ali O; Buchanan, Ann; Boren, Jake; Allen, Timothy; Rahman, Najib M; Koenig, Kathleen; Chamiso, Mignote; Karandashova, Sophia; Henry, James; Idell, Steven

2016-08-01

The incidence of empyema (EMP) is increasing worldwide; EMP generally occurs with pleural loculation and impaired drainage is often treated with intrapleural fibrinolytic therapy (IPFT) or surgery. A number of IPFT options are used clinically with empiric dosing and variable outcomes in adults. To evaluate mechanisms governing intrapleural fibrinolysis and disease outcomes, models of Pasteurella multocida and Streptococcus pneumoniae were generated in rabbits and the animals were treated with either human tissue (tPA) plasminogen activator or prourokinase (scuPA). Rabbit EMP was characterized by the development of pleural adhesions detectable by chest ultrasonography and fibrinous coating of the pleura. Similar to human EMP, rabbits with EMP accumulated sizable, 20- to 40-ml fibrinopurulent pleural effusions associated with extensive intrapleural organization, significantly increased pleural thickness, suppression of fibrinolytic and plasminogen-activating activities, and accumulation of high levels of plasminogen activator inhibitor 1, plasminogen, and extracellular DNA. IPFT with tPA (0.145 mg/kg) or scuPA (0.5 mg/kg) was ineffective in rabbit EMP (n = 9 and 3 for P. multocida and S. pneumoniae, respectively); 2 mg/kg tPA or scuPA IPFT (n = 5) effectively cleared S. pneumoniae-induced EMP collections in 24 h with no bleeding observed. Although intrapleural fibrinolytic activity for up to 40 min after IPFT was similar for effective and ineffective doses of fibrinolysin, it was lower for tPA than for scuPA treatments. These results demonstrate similarities between rabbit and human EMP, the importance of pleural fluid PAI-1 activity, and levels of plasminogen in the regulation of intrapleural fibrinolysis and illustrate the dose dependency of IPFT outcomes in EMP. Copyright © 2016 the American Physiological Society.

Electromagnetic pulse activated brain microglia via the p38 MAPK pathway.

PubMed

Yang, Long-Long; Zhou, Yan; Tian, Wei-Dong; Li, Hai-Juan; Kang-Chu-Li; Miao, Xia; An, Guang-Zhou; Wang, Xiao-Wu; Guo, Guo-Zhen; Ding, Gui-Rong

2016-01-01

Previously, we found that electromagnetic pulses (EMP) induced an increase in blood brain barrier permeability and the leakage of albumin from blood into brain tissue. Albumin is known to activate microglia cells. Thus, we hypothesised that microglia activation could occur in the brain after EMP exposure. To test this hypothesis, the morphology and secretory function of microglia cells, including the expression of OX-42 (a marker of microglia activation), and levels of TNF-α, IL-10, IL-1β, and NO were determined in the rat cerebral cortex after EMP exposure. In addition, to examine the signalling pathway of EMP-induced microglia activation, protein and phosphorylated protein levels of p38, JNK and ERK were determined. It was found that the expression of OX-42increased significantly at 1, 6 and 12h (p<0.05) and recovered to the sham group level at 24h after EMP exposure. Levels of NO, TNF-α and IL-10 also changed significantly in vivo and in vitro after EMP exposure. The protein level of p38 and phosphorylated p38 increased significantly after EMP exposure (p<0.05) and recovered to sham levels at 12 and 24h, respectively. Protein and phosphorylated protein levels of ERK and JNK did not change. SB203580 (p38 inhibitor) partly prevented the change in NO, IL-10, IL-1β, TNF-α levels induced by EMP exposure. Taken together, these results suggested that EMP exposure (200kV/m, 200 pulses) could activate microglia in rat brain and affect its secretory function both in vivo and in vitro, and the p38 pathway is involved in this process. Copyright © 2015 Elsevier Inc. All rights reserved.

EMP combination chemotherapy and low-dose monotherapy in advanced prostate cancer.

PubMed

Kitamura, Tadaichi; Nishimatsu, Hiroaki; Hamamoto, Toshiaki; Tomita, Kyoichi; Takeuchi, Takumi; Ohta, Nobutaka

2002-02-01

Many chemotherapeutic regimens combined with estramustine phosphate (EMP) have been elaborated for the treatment of hormone-refractory prostate cancer over 30 years. However, older EMP-based combination chemotherapies with vinblastine, vinorelbine, doxorubicin or cyclophosphamide showed relatively low PSA response rate (25-58%) accompanied with high toxicities. On the other hand, newly developed EMP-based combination regimens with etoposide, pacitaxel, carboplatin or docetaxel demonstrated promising PSA response rate (43-77%) with moderate to severe toxicity in the rate of thromboembolic event (5-18%) and of neutropenia (9-41%). Treatment-related death was less in the latter combination group (5/615, 0.8%) than that in the former group (3/234, 1.3%). Of note, in the docetaxel combination with EMP, PSA response rate is as high as 77% with high rate (41%) of neutropenia but no treatment-related death was observed. Docetaxel combination with EMP seems to be the best regimen, though not completely justified by randomized trials, to be selected in the modern era, which will be followed by paclitaxel, carboplatin and EMP combination with PSA response rate of 71%. In addition, an interim report in 83 patients was presented. They were not consecutively enrolled but were treated on low-dose EMP monotherapy for previously untreated advanced prostate cancer in Department of Urology of Tokyo University and our 21 affiliated hospitals. Overall PSA response rate was as high as 93.4% out of 76 assessable patients. However, overall toxicity rate was abnormally high (39.5%) with drug discontinuation rate of 32.1%. The reason of low drug compliance may be attributed to gastrointestinal symptoms. To overcome the low drug compliance, appropriate patients for EMP administration should be selected by using gene analysis on the basis of sophisticated tailor-made medicine.

Effects of High Intensity Training and High Volume Training on Endothelial Microparticles and Angiogenic Growth Factors

PubMed Central

Achtzehn, Silvia; Schmitz, Theresa; Bloch, Wilhelm; Mester, Joachim; Werner, Nikos

2014-01-01

Aims Endothelial microparticles (EMP) are complex vesicular structures shed from activated or apoptotic endothelial cells. As endurance exercise affects the endothelium, the objective of the study was to examine levels of EMP and angiogenic growth factors following different endurance exercise protocols. Methods 12 subjects performed 3 different endurance exercise protocols: 1. High volume training (HVT; 130 min at 55% peak power output (PPO); 2. 4×4 min at 95% PPO; 3. 4×30 sec all-out. EMPs were quantified using flow cytometry after staining platelet-poor-plasma. Events positive for Annexin-V and CD31, and negative for CD42b, were classified as EMPs. Vascular endothelial growth factor (VEGF), migratory inhibiting factor (MIF) and hepatocyte growth factor (HGF) were determined by ELISA technique. For all these measurements venous blood samples were taken pre, 0′, 30′, 60′ and 180′ after each intervention. Furthermore, in vitro experiments were performed to explore the effect of collected sera on target endothelial functions and MP uptake capacities. Results VEGF and HGF significantly increased after HIT interventions. All three interventions caused a significant decrease in EMP levels post exercise compared to pre values. The sera taken after exercise increased the uptake of EMP in target endothelial cells compared to sera taken under resting conditions, which was shown to be phosphatidylserin-dependent. Increased EMP uptake was associated with an improved protection of target cells against apoptosis. Sera taken prior and after exercise promoted target endothelial cell migration, which was abrogated after inhibition of VEGF. Conclusion Physical exercise leads to decreased EMP levels and promotes a phosphatidylserin-dependent uptake of EMP into target endothelial cells, which is associated with a protection of target cells against apoptosis. PMID:24770423

Neoadjuvant luteinizing-hormone-releasing hormone agonist plus low-dose estramustine phosphate improves prostate-specific antigen-free survival in high-risk prostate cancer patients: a propensity score-matched analysis.

PubMed

Koie, Takuya; Mitsuzuka, Koji; Yoneyama, Takahiro; Narita, Shintaro; Kawamura, Sadafumi; Kaiho, Yasuhiro; Tsuchiya, Norihiko; Tochigi, Tatsuo; Habuchi, Tomonori; Arai, Yoichi; Ohyama, Chikara; Yoneyama, Tohru; Tobisawa, Yuki

2015-10-01

The optimal treatment for high-risk prostate cancer (Pca) remains to be established. We previously reported favorable biochemical recurrence-free survival (BRFS) in high-risk Pca patients treated with a neoadjuvant therapy comprising a luteinizing-hormone-releasing hormone (LHRH) agonist plus low dose estramustine phosphate (EMP) (LHRH+EMP) followed by radical prostatectomy (RP). In the present study, we used a retrospective design via propensity score matching to elucidate the clinical benefit of neoadjuvant LHRH+EMP for high-risk Pca. The Michinoku Urological Cancer Study Group database contained data for 1,268 consecutive Pca patients treated with RP alone at 4 institutions between April 2000 and March 2011 (RP alone group). In the RP alone group, we identified 386 high-risk Pca patients. The neoadjuvant LHRH+EMP group included 274 patients with high-risk Pca treated between September 2005 and November 2013 at Hirosaki University. Neoadjuvant LHRH+EMP therapy included LHRH and EMP administration at a dose of 280 mg/day for 6 months before RP. The outcome measures were overall survival (OS) and BRFS. The propensity score-matched analysis indicated 210 matched pairs from both groups. The 5-year BRFS rates were 90.4 and 65.8 % for the neoadjuvant LHRH+EMP and RP alone groups, respectively (P < 0.0001). The 5-year OS rates were 100 and 96.1 % for the neoadjuvant LHRH+EMP and RP alone groups, respectively (P = 0.110). Although the present study was not randomized, neoadjuvant LHRH+EMP therapy followed by RP appeared to reduce the risk of biochemical recurrence. A prospective randomized study is warranted to determine the clinical implications of the neoadjuvant therapy described here.

Endothelial microparticle-mediated transfer of MicroRNA-126 promotes vascular endothelial cell repair via SPRED1 and is abrogated in glucose-damaged endothelial microparticles.

PubMed

Jansen, Felix; Yang, Xiaoyan; Hoelscher, Marion; Cattelan, Arianna; Schmitz, Theresa; Proebsting, Sebastian; Wenzel, Daniela; Vosen, Sarah; Franklin, Bernardo S; Fleischmann, Bernd K; Nickenig, Georg; Werner, Nikos

2013-10-29

Repair of the endothelium after vascular injury is crucial for preserving endothelial integrity and preventing the development of vascular disease. The underlying mechanisms of endothelial cell repair are largely unknown. We sought to investigate whether endothelial microparticles (EMPs), released from apoptotic endothelial cells (ECs), influence EC repair. Systemic treatment of mice with EMPs after electric denudation of the endothelium accelerated reendothelialization in vivo. In vitro experiments revealed that EMP uptake in ECs promotes EC migration and proliferation, both critical steps in endothelial repair. To dissect the underlying mechanisms, Taqman microRNA array was performed, and microRNA (miR)-126 was identified as the predominantly expressed miR in EMPs. The following experiments demonstrated that miR-126 was transported into recipient human coronary artery endothelial cells by EMPs and functionally regulated the target protein sprouty-related, EVH1 domain-containing protein 1 (SPRED1). Knockdown of miR-126 in EMPs abrogated EMP-mediated effects on human coronary artery endothelial cell migration and proliferation in vitro and reendothelialization in vivo. Interestingly, after simulating diabetic conditions, EMPs derived from glucose-treated ECs contained significantly lower amounts of miR-126 and showed reduced endothelial repair capacity in vitro and in vivo. Finally, expression analysis of miR-126 in circulating microparticles from 176 patients with stable coronary artery disease with and without diabetes mellitus revealed a significantly reduced miR-126 expression in circulating microparticles from diabetic patients. Endothelial microparticles promote vascular endothelial repair by delivering functional miR-126 into recipient cells. In pathological hyperglycemic conditions, EMP-mediated miR-126-induced EC repair is altered.

Catabolic effects of endothelial cell-derived microparticles on disc cells: Implications in intervertebral disc neovascularization and degeneration.

PubMed

Pohl, Pedro H I; Lozito, Thomas P; Cuperman, Thais; Yurube, Takashi; Moon, Hong J; Ngo, Kevin; Tuan, Rocky S; St Croix, Claudette; Sowa, Gwendolyn A; Rodrigues, Luciano M R; Kang, James D; Vo, Nam V

2016-08-01

Neovascularization of intervertebral discs, a phenomenon considered pathological since normal discs are primarily avascular structures, occurs most frequently in annulus fibrosus (AF) of degenerated discs. Endothelial cells (ECs) are involved in this process, but the mechanism of the interaction between AF and endothelial cells is unclear. In this study, we evaluated the effects on matrix catabolic activity of AF cells by the extracellular endothelial microparticles (EMPs) and soluble protein factors (SUP fraction) produced from ECs. Passage 1 human AF cells grown in monolayer cultures were treated for 72 h with 250 µg of EMPs or SUP fraction isolated from culture of the microvascular endothelial cell line, HEMC-I. Live-cell imaging revealed uptake of EMPs by AF cells. RT-PCR analysis demonstrated increased mRNA expression of MMP-1 (50.3-fold), MMP-3 (4.5-fold) and MMP-13 (5.5-fold) in AF cell cultures treated with EMPs compared to untreated control. Western analysis also demonstrated increased MMP protein expression in EMP-treated AF cells. AF cells treated with the SUP fraction also exhibited a dramatic increase in MMP mRNA and protein expression. Increased MMP expression is primarily due to EMP or SUP stimulation of AF cells since EMPs or SUP fraction alone contained negligible amount of MMPs. Interestingly, MMP activity was elevated in AF cell cultures treated with EMPs but not with SUP. This study revealed enhanced matrix catabolism as a molecular consequence of action of ECs on AF cells via EMPs, which might be expected during neo-angiogenesis of degenerating disc. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1466-1474, 2016. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

San Francisco Estuary Striped Bass Migration History Determined by Electron-microprobe Analysis of Otolith Sr/Ca Ratio

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

Ostrach, D J; Phillis, C C; Weber, P K

2004-09-17

Habitat use has been shown to be an important factor in the bioaccumulation of contaminants in striped bass. This study examines migration in striped bass as part of a larger study investigating bioaccumulation and maternal transfer of xenobiotics to progeny in the San Francisco Estuary system. Habitat use, residence time and spawning migration over the life of females (n = 23) was studied. Female striped bass were collected between Knights Landing and Colusa on the Sacramento River during the spawning runs of 1999 and 2001. Otoliths were removed, processed and aged via otolith microstructure. Subsequently, otoliths were analyzed for strontium/calciummore » (Sr/Ca) ratio using an electron-microprobe to measure salinity exposure and to distinguish freshwater, estuary, and marine habitat use. Salinity exposure during the last year before capture was examined more closely for comparison of habitat use by the maternal parent to contaminant burden transferred to progeny. Results were selectively confirmed by ion microprobe analyses for habitat use. The Sr/Ca data demonstrate a wide range of migratory patterns. Age of initial ocean entry differs among individuals before returning to freshwater, presumably to spawn. Some fish reside in freshwater year-round, while others return to more saline habitats and make periodic migrations to freshwater. Frequency of habitat shifts and residence times differs among fish, as well as over the lifetime of individual fish. While at least one fish spent its final year in freshwater, the majority of spawning fish spent their final year in elevated salinity. However, not all fish migrated to freshwater to spawn in the previous year. Results from this investigation concerning migration history in striped bass can be combined with contaminant and histological developmental analyses to better understand the bioaccumulation of contaminants and the subsequent effects they and habitat use have on fish populations in the San Francisco Estuary system.« less

Design of a bounded wave EMP (Electromagnetic Pulse) simulator

NASA Astrophysics Data System (ADS)

Sevat, P. A. A.

1989-06-01

Electromagnetic Pulse (EMP) simulators are used to simulate the EMP generated by a nuclear weapon and to harden equipment against the effects of EMP. At present, DREO has a 1 m EMP simulator for testing computer terminal size equipment. To develop the R and D capability for testing larger objects, such as a helicopter, a much bigger threat level facility is required. This report concerns the design of a bounded wave EMP simulator suitable for testing large size equipment. Different types of simulators are described and their pros and cons are discussed. A bounded wave parallel plate type simulator is chosen for it's efficiency and the least environmental impact. Detailed designs are given for 6 m and 10 m parallel plate type wire grid simulators. Electromagnetic fields inside and outside the simulators are computed. Preliminary specifications for a pulse generator required for the simulator are also given. Finally, the electromagnetic fields radiated from the simulator are computed and discussed.

The role of protein kinase C in the opening of blood-brain barrier induced by electromagnetic pulse.

PubMed

Qiu, Lian-Bo; Ding, Gui-Rong; Li, Kang-Chu; Wang, Xiao-Wu; Zhou, Yan; Zhou, Yong-Chun; Li, Yu-Rong; Guo, Guo-Zhen

2010-06-29

The aim of this study was to determine the role of protein kinase C signaling in electromagnetic pulse (EMP)-induced blood-brain barrier (BBB) permeability change in rats. The protein level of total PKC and two PKC isoforms (PKC-alpha, and PKC-beta II) were determined in brain cerebral cortex microvessels by Western blot after exposing rats to EMP at 200kV/m for 200 pulses with 1Hz repetition rate. It was found that the protein level of PKC and PKC-betaII (but not PKC-alpha) in cerebral cortex microvessels increased significantly at 0.5h and 1h after EMP exposure compared with sham-exposed animals and then recovered at 3h. A specific PKC antagonist (H7) almost blocked EMP-induced BBB permeability change. EMP-induced BBB tight junction protein ZO-1 translocation was also inhibited. Our data indicated that PKC signaling was involved in EMP-induced BBB permeability change and ZO-1 translocation in rat.

Nucleosynthesis in Hot Bubbles of SNe-Origin of EMP Stars: HNe or SNe ?

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

Izutani, Natsuko; Umeda, Hideyuki; Yoshida, Takashi

2010-08-12

The observational trends of extremely metal-poor (EMP) stars reflect SN nucleosynthesis of Population III, or almost metal-free stars. The observation of EMP stars can be reproduced by HNe, not by normal SNe. However, if the innermost neutron-rich or proton-rich matter is ejected, the abundance patterns of ejected matter are changed, and there is a possibility that normal SNe can also reproduce the observations of EMP stars. In this paper, we calculate nucleosynthesis with various Y{sub e} and entropy taking into account neutrino processes. We investigate whether normal SNe with this innermost matter can reproduce the observations of EMP stars. Wemore » find that neutron-rich (Y{sub e} = 0.45-0.50) and proton-rich (Y{sub e} = 0.51-0.55) matters can improve Zn and Co, but tend to overproduce other Fe-peak elements. On the other hand, HNe can naturally reproduce the observations of EMP stars.« less

Rock magnetic properties of iron-rich Chicxulub impact ejecta from La Sierrita, northeastern Mexico

NASA Astrophysics Data System (ADS)

Kontny, A.; Schulte, P.; Stinnesbeck, W.

2002-12-01

Chicxulub ejecta deposits from La Sierrita, NE Mexico, are composed mainly of mm-cm sized vesicular spherules and (ejecta-) fragments that consist of Fe- and Mg-rich chlorite, opaque phases, and calcite infillings. Their Fe-rich and Si-poor composition may be indicative of contribution to the ejecta from mafic target rocks (Schulte et al., this meeting). This study addresses the magnetic mineralogy and properties of these ejecta deposits, since they could provide clues to target lithologies, physical conditions during the impact (quenching, crystallization, oxidation), and diagenetic processes. Optical microscopy, backscattered electron images, and electron microprobe (EMP) analyses show that opaque phases within spherules and fragments (even in calcite infillings) are hematite, goethite, rutile, and Ti-Fe oxides. Cubic and hexagonal hematite crystals are up to 20 μm in size and show a zonar composition with elevated Si (4-8 wt%) and Ni (up to 0.4 wt%) concentrations in the cores of crystals. Hematite formed either primary from melt or as replacement product of cubic minerals such as magnetite or pyrite during diagenesis. Garland-shaped, Ti- and Fe-rich lamellae are present with grain sizes of the opaque minerals below the resolution of the EMP; rutile and Ti-Fe oxide phases within these lamellae show crystal sizes growing towards the interior of grains. Some Ti-Fe oxides also show dendritic or skeletal crystals with spinifex textures that may be indicative of quenching. The volume magnetic susceptibility (MS) of ejecta deposits show relatively homogeneous paramagnetic values between 6 and 30 x 10-6 SI/g that correlate well with the bulk Fe-content and are enhanced as compared to the surrounding marls and sandstones. In the range from -192 to 700°C, temperature-dependent MS shows a dominant exponential decrease, thus confirming the paramagnetic behavior. However, a small peak at about -80°C is superimposed on the paramagnetic curve. This peak either indicates a Curie or Néel temperature or reflects a grain-size effect of a ferromagnetic phase. The heating leg of the MS(T) curve generally displays constant low MS values. However, heating and cooling runs are irreversible and the cooling leg displays two Curie temperatures (TC) at 570 and 480°C, thus indicating transformation during heating of iron-bearing minerals into magnetite or magnetite-near phases. No characteristic TC related either to hematite or to goethite has been detected; this absence could be related to impurities (Si, Ni) or cation deficiency. Intensity of the natural remanent magnetization (NRM) of the ejecta deposits is very small (0.3-0.7 mA/m). In fields below 10 mT, alternating field-demagnetization of NRM shows initial rapid decrease of about 50 % of the original intensity, whereas in fields of 160 mT no further demagnetization occurs. Induced remanent magnetization (IRM) acquisition curves reveal that some studied samples are nearly saturated in fields of 1000 mT while others are not. Furthermore, the IRM data confirm the presence of a single dominant high coercive mineral such as hematite and goethite; these are the main iron-bearing magnetic phases, in addition to chlorite. The occurrence of hematite and goethite in the La Sierrita ejecta points to highly oxidizing conditions during or after ejecta formation. Such conditions may have prevented the origination of stronger (ferro-) magnetic phases (e.g. magnetite) or destroyed them.

Electromagnetic Pulse (EMP) Handbook for Air Force Communications Service Communications-Electronics-Meteorological Engineers

DTIC Science & Technology

1976-11-01

protec- tion and will require additional measures, such as the application of conductive filter-loaded plastic resins to each joint connection...Lawrence Liver- more Laboratory, Livermore CA, 1974 31. Whitson, A. L., "DCA HEMP Hardness Certification Methodology Status", Stanford Research...of Chief of Engineers, Depot of the Army, December 1971 34. "Development of HEMP Assessment Methodology for Satellite Terminals", Intelcom Rad Tech

The measurement of lightning environmental parameters related to interaction with electronic systems

NASA Technical Reports Server (NTRS)

Baum, C. E.; Breen, E. L.; Pitts, F. L.; Thomas, M. E.; Sower, G. D.

1982-01-01

The measurement of electromagnetic fields and related quantities in a lightning environment is a challenging problem, especially at high frequencies and/or in the immediate vicinity of the lightning arcs and corona. This paper reviews the techniques for accomplishing such measurements in these regimes with examples. These sensors are often the same as for the nuclear electromagnetic pulse (EMP), but significant differences also appear.

Optically Levitated Targets as a Source for High Brightness X-rays and a Platform for Mass-Limited Laser-interaction Experiments

NASA Astrophysics Data System (ADS)

Giltrap, Samuel; Stuart, Nick; Robinson, Tim; Armstrong, Chris; Hicks, George; Eardley, Sam; Gumbrell, Ed; Smith, Roland

2016-10-01

Here we report on the development of an optical levitation based x-ray and proton source, motivated by the requirement for a debris free, high spatial resolution, and low EMP source for x-ray radiography and proton production. Research at Imperial College has led to the development of a feedback controlled optical levitation trap which is capable of holding both solid (Glass beads) and liquid (silicon based oil) micro-targets ( 3-10um). The optical levitation trap has been successfully fielded in a high-intensity laser interaction experiment at Imperial College London and at the Vulcan Petawatt Laser system at the Rutherford Appleton Laboratory (RAL). Here we report on the results from that RAL run including; an x-ray source size of 10-15um with very good spherical symmetry when compared to wire targets, secondly very low EMP signal from isolated levitated targets (9 times less RF signal than a comparable wire target). At Imperial College we were also able to record an x-ray energy spectrum which produced an electron temperature of 0.48KeV, and performed interferometry of a shock evolving into a blast wave off an optically levitated droplet which allowed us to infer the electron density within the shock front.

Down-regulation of EMP1 is associated with epithelial hyperplasia and metaplasia in nasal polyps.

PubMed

Yu, Xue Min; Li, Chun Wei; Li, Ying Ying; Liu, Jing; Lin, Zhi Bin; Li, Tian Ying; Zhao, Li; Pan, Xin Liang; Shi, Li; Wang, De Yun

2013-11-01

The aim of this study was to assess protein and mRNA expression of epithelial membrane protein 1 (EMP1) in the nasal mucosa of patients with nasal polyps (NP), and to determine what changes occur in response to glucocorticosteroid (GC) treatment. NP tissue was obtained from 55 patients, 18 of whom were treated with nasal GCs (i.e. these 18 patients had NP biopsies taken before and after treatment). Biopsies of inferior turbinate mucosa from 30 healthy subjects were used as controls. Quantitative PCR and immunohistochemistry were performed to determine the expression levels of EMP1. EMP1 mRNA expression was significantly lower (2.77-fold) in tissues from NP patients before GC treatment when compared to controls, but was increased in these patients after GC treatment. EMP1 staining in nasal epithelium co-localized with both basal (p63(+)) and differentiated (CK18(+)) epithelial cells. Their immunoreactivity was significantly greater in controls than NP patients. EMP1 mRNA levels were lower in the epithelium with severe hyperplasia (1.79-fold) or with metaplasia (1.85-fold) as compared to those with mild to moderate hyperplasia or non-metaplastic epithelium, respectively. Positive correlations between EMP1 and other epithelial cell-related gene (e.g. JUN, PTGS2, AREG etc.) mRNAs were observed. EMP1 could be a biomarker for aberrant epithelial remodelling and metaplasia in chronic inflammatory upper airway mucosa (e.g. NP). © 2013 John Wiley & Sons Ltd.

[Effects of electromagnetic pulses on apoptosis and TGF-β3 expression of mouse testis tissue].

PubMed

Luo, Yaning; Ding, Guirong; Chen, Yongbin; Xu, Shenglong; Wang, Xiaowu

2014-04-01

To investigate the effects of electromagnetic pulses (EMP) on the apoptosis and transforming growth factor beta 3 (TGF-β3) expression of mouse testis tissue. Thirty-two male BALB/c mice were randomly and equally divided into one control group and three EMP treated groups, which were whole-body exposed to EMP at 200 kV/m with 100, 200, and 400 pulses, respectively. The control group received no treatment. The pathological changes and cell apoptosis in testis tissue were analyzed by TUNEL assay. The mRNA expression of TGF-β3 in testis tissue was determined by RT-PCR, and the protein expression of TGF-β3 was determined by immunohistochemistry and Western blot. No obvious pathological changes were found in testis tissue after EMP exposure at 200 kV/m with 100 and 200 pulses. However, after EMP exposure with 400 pulses, degeneration and shedding of testis tissue, accompanied by significant increase in apoptosis rate (P < 0.05), was observed. The RT-PCR, immunohistochemistry, and Western blot showed that the expression of TGF-β3 mRNA and protein increased significantly after EMP exposure with 400 pulses as compared with that of the control group (P < 0.05). EMP exposure at 200 kV/m with 400 pulses increases the incidence of apoptosis and expression of TGF-β3 in mouse testis tissue, which is potentially one of the mechanisms by which EMP increases blood-testis barrier permeability in mice.

Clinical analysis of 40 multiple myeloma patients with extramedullary plasmacytoma of the head

PubMed Central

Sun, Wan-jun; Zhang, Jia-jia; An, Na; Shen, Men; Huang, Zhong-xia

2016-01-01

Objectives To investigate the clinical characteristics, survival and prognosis of patients with multiple myeloma (MM) and head extramedullary plasmacytoma (EMP). Methods Forty MM patients were enrolled in the study (18 men, 22 women; median age, 55 years). Results Median overall survival (OS) and progression-free survival (PFS) were 24 (5–78) months and 17 (2–36) months, respectively. The 2-, 3- and 5-year OS rates were 51%, 20% and 7%, respectively. The 2-year PFS was 15%. Median OS and PFS in patients administered velcade were 26 (18–50) and 22.5 (5–78) months, compared with 20 (10–30) and 13.5 (2–36) months in patients without velcade, respectively. Median OS was 23.5 (5–50) months in patients with EMP at MM diagnosis (n = 25) and 36 (22–78) months in patients with head EMP diagnosed during the disease course (n = 15). Sixteen MM patients had EMP invasion of the head only and 24 had invasion at multiple sites. Median OS was 25 (22–78) months in patients with EMP of the head only and 22 (5–78) months in patients with EMP invasion at multiple sites. Conclusion MM patients with head EMP show a more aggressive disease course and shorter OS and PFS. The prognosis of these patients is poor, especially in patients with head EMP at MM diagnosis, though combined chemotherapy and radiotherapy may prolong survival. PMID:28322099

SXRF determination of trace elements in chondrule rims in the unequilibrated CO3 chondrite, ALH A77307

NASA Technical Reports Server (NTRS)

Brearley, Adrian J.; Bajt, Sasa; Sutton, Steve R.; Papike, J. J.

1993-01-01

The concentrations of Ni, Cu, Zn, Ga, Ge, and Se in five chondrule rims in the CO3 chondrite ALH A77307 (3.0) using the synchrotron x-ray fluorescence (SXRF) microprobe at Brookhaven National Laboratory were determined. The data show that the trace element chemistry of rims on different chondrules is remarkably similar, consistent with data obtained for the major elements by electron microprobe. These results support the idea that rims are not genetically related to individual chondrules, but all sampled the same reservoir of homogeneously mixed dust. Of the trace elements analyzed Zn and Ga show depletions relative to CI chondrite values, but in comparison with bulk CO chondrites all the elements are enriched by approximately 1.5 to 3.5 x CO. The high concentrations of the highly volatile elements Se and Ga and moderately volatile Zn (1.5 to 2 x CO) in rims show that matrix is the major reservoir of volatile elements in ALH A77307.

Development of an external beam nuclear microprobe on the Aglae facility of the Louvre museum

NASA Astrophysics Data System (ADS)

Calligaro, T.; Dran, J.-C.; Ioannidou, E.; Moignard, B.; Pichon, L.; Salomon, J.

2000-03-01

The external beam line of our facility has been recently equipped with the focusing system previously mounted on a classical nuclear microprobe. When using a 0.1 μm thick Si 3N 4 foil for the exit window and flowing helium on the sample under analysis, a beam spot as small as 10 μm is attainable at a distance of 3 mm from the window. Elemental micromapping is performed by mechanical scanning. An electronic device has been designed which allows XY scanning by moving the sample under the beam by steps down to 0.1 μm. Beam monitoring is carried out by means of the weak X-ray signal emitted by the exit foil and detected by a specially designed Si(Li) detector cooled by Peltier effect. The characteristics of external beams of protons and alpha particles are evaluated by means of resonance scanning and elemental mapping of a grid. An example of application is presented, dealing with elemental micro-mapping of inclusions in gemstones.

Impact of EMP on Air Operations

DTIC Science & Technology

pulse while in flight. With a requirement to be compliant with this standard for all critical weapon systems, the C -17 remains untested. The significant...EMP event that would threaten an inflight C -17, there was not enough evidence to force a change to the current EMP testing and hardening schedule.

Effects of electromagnetic pulse on bone metabolism of mice in vivo.

PubMed

Li, Kang-Chu; Ma, Shi-Rong; Ding, Gui-Rong; Guo, Yao; Guo, Guo-Zhen

2009-12-01

To study the effects of electromagnetic pulse (EMP) on bone metabolism of mice in vivo. Twenty-four male BALB/c mice were divided into a control group and 2 experimental groups (n=8). The whole-body of mice in experimental groups were exposed to 50 kV/m and 400kV/m EMP, 400 pulses daily for 7 consecutive days at 2 seconds intervals. Alkaline phosphotase (ALP) activity, serum calcium concentration and osteocalcin level and trabecular bone volume (BV/TV, %) were measured immediately after EMP exposure by biochemical, ELISA and morphological methods. The ALP activity, serum calcium concentration and osteocalcin level and BV/TV in experimental groups remained unchanged after EMP exposure. Conclusion Under our experimental conditions, EMP exposure cannot affect bone metabolism of mice in vivo.

Iron-regulated biofilm formation in Staphylococcus aureus Newman requires ica and the secreted protein Emp.

PubMed

Johnson, Miranda; Cockayne, Alan; Morrissey, Julie A

2008-04-01

Staphylococcus aureus biofilm formation is induced in iron-restricted growth conditions in vitro. In this study, we showed that Emp and Eap play important roles in low-iron-induced biofilm formation of S. aureus Newman. Eap and Emp are secreted proteins which are non-covalently attached to the S. aureus cell surface and have previously been implicated in a number of aspects of S. aureus pathogenesis. We showed here that the transcription of these important virulence factors is induced by growth in low-iron medium, reflective of the in vivo environment. Our results show that iron regulation of Eap and Emp is Fur independent. However, Fur is required for full induction of eap and emp expression in low-iron conditions. In this study, we demonstrated that in addition to Fur, low-iron-induced biofilm formation requires Sae, Agr, and SarA. In iron-restricted growth conditions, Sae and Agr are essential for Emp and Eap expression and hence for biofilm formation, whereas SarA appears to have a less-significant role. We also showed that expression of the ica operon is required for biofilm formation in iron-restricted growth conditions. We demonstrated that in fact, ica is required for the expression of the important multifunctional virulence determinants eap and emp.

Structure and biological activities of eumenine mastoparan-AF (EMP-AF), a new mast cell degranulating peptide in the venom of the solitary wasp (Anterhynchium flavomarginatum micado).

PubMed

Konno, K; Hisada, M; Naoki, H; Itagaki, Y; Kawai, N; Miwa, A; Yasuhara, T; Morimoto, Y; Nakata, Y

2000-11-01

A new mast cell degranulating peptide, eumenine mastoparan-AF (EMP-AF), was isolated from the venom of the solitary wasp Anterhynchium flavomarginatum micado, the most common eumenine wasp found in Japan. The structure was analyzed by FAB-MS/MS together with Edman degradation, which was corroborated by solid-phase synthesis. The sequence of EMP-AF, Ile-Asn-Leu-Leu-Lys-Ile-Ala-Lys-Gly-Ile-Ile-Lys-Ser-Leu-NH(2), was similar to that of mastoparan, a mast cell degranulating peptide from a hornet venom; tetradecapeptide with C-terminus amidated and rich in hydrophobic and basic amino acids. In fact, EMP-AF exhibited similar activity to mastoparan in stimulating degranulation from rat peritoneal mast cells and RBL-2H3 cells. It also showed significant hemolytic activity in human erythrocytes. Therefore, this is the first example that a mast cell degranulating peptide is found in the solitary wasp venom. Besides the degranulation and hemolytic activity, EMP-AF also affects on neuromuscular transmission in the lobster walking leg preparation. Three analogs EMP-AF-1 approximately 3 were snythesized and biologically tested together with EMP-AF, resulting in the importance of the C-terminal amide structure for biological activities.

Restrain of bone growth by estrogen-mimetic peptide-1 (EMP-1): a micro-computed tomographic study.

PubMed

Kasher, Roni; Bajayo, Alon; Gabet, Yankel; Nevo, Nava; Fridkin, Mati; Katchalski-Katzir, Ephraim; Kohen, Fortune; Bab, Itai

2009-06-01

Estrogen has a key role in the regulation of skeletal growth and maintenance of bone mass. Recently, we developed peptides having estrogen-like activity as potential estrogen-based new drugs. The aim of the present study was to evaluate the influence of long-term administration of the most efficacious of these peptides, the hexapeptide EMP-1 (VSWFFE), on bone mass and development. EMP-1 was injected daily to ovariectomized (OVX) and intact young, sexually mature female mice for 10 weeks. Whole femora, including the cartilaginous growth plates were analyzed by micro-computed tomography (microCT). We found that peptide EMP-1 restrains bone growth in OVX mice: it inhibited dramatically bone longitudinal growth (40%), and decreased femoral diaphyseal diameter. Peptide EMP-1 had no effect on bone growth in normal mice, and did not influence the OVX-induced bone loss. We then developed a new microCT methodology to evaluate uncalcified and calcified growth plate parameters. In the OVX mice, peptide EMP-1 reduced volume and thickness of the uncalcified growth plate, a possible cause for the inhibition of bone longitudinal growth. Peptide EMP-1 may be used as a lead compound for the development of drugs to treat acromegalic patients.

[Effects of electromagnetic pulse exposure on the morphological change and excretion function of BV-2 cells and possible mechanism].

PubMed

Yang, Long-long; Zhou, Yan; Li, Hai-juan; Guo, Juan; Zhang, Yan-jun; Ding, Gui-rong; Guo, Guo-zhen

2012-03-01

To study the effects of electromagnetic pulse (EMP) exposure on the morphological change and excretion functions of mouse microglia (BV-2) cells and possible mechanism. BV-2 cells were divided into two groups: the group exposed to EMP at 200 kV/m for 200 pulses and sham exposure group. At 1, 6, 12 and 24 hour after exposure the cells and culture supernatant were collected. Cellular morphological change was observed under invert microscope, the levels of TNF-α, IL-1β and IL-10 in culture supernatant were determined by enzyme-linked immunosorbent assay (ELISA), nitric oxide (NO) and reactive oxygen species (ROS) were detected by nitrate reductase method and DCFH-DA probe, respectively. The protein and phosphorylation levels of ERK, JNK and p38 were measured by Western Blot method. After the cells pre-treated with the inhibitor of p38 (SB203580) were exposed to EMP, the levels of NO and ROS in culture supernatant were detected. It was found that the large ameboid shape appeared in some microglia cells exposed to EMP for 1, 6 and 12 h. Moreover, the number of microglia cells with ameboid shape increased significantly at 1 h, 6 h and 12 h after EMP exposure compared with sham group (P < 0.05). The levels of cytokines, such as TNF-α, IL-1β and IL-10, in culture supernatant did not change obviously after EMP exposure. The levels of NO and ROS increased significantly at 1h after EMP exposure, reached the peak at 6 h, began to recover at 12 h and recovered to sham group level at 24 h (P < 0.05). Western blot results showed that the protein and protein phosphorylation levels of ERK and JNK did not change significantly after EMP exposure, however, the protein and protein phosphorylation levels of p38 increased obviously at 1 h and 6 h after EMP exposure, compared with sham group (P < 0.05). In addition, the pretreatment of p38 inhibitor (SB203580) significantly decreased NO and ROS production induced by EMP. EMP exposure may activate microglia cells and promote the production of NO and ROS in mouse microglia cells, and p38 pathway is involved in this process.

In vivo deployment of mechanically adaptive nanocomposites for intracortical microelectrodes

PubMed Central

Harris, J P; Hess, A E; Rowan, S J; Weder, C; Zorman, C A; Tyler, D J; Capadona, J R

2012-01-01

We recently introduced a series of stimuli-responsive, mechanically-adaptive polymer nanocomposites. Here, we report the first application of these bio-inspired materials as substrates for intracortical microelectrodes. Our hypothesis is that the ideal electrode should be initially stiff to facilitate minimal trauma during insertion into the cortex, yet becomes mechanically compliant to match the stiffness of the brain tissue and minimize forces exerted on the tissue, attenuating inflammation. Microprobes created from mechanically reinforced nanocomposites demonstrated a significant advantage compared to model microprobes composed of neat polymer only. The nanocomposite microprobes exhibit a higher storage modulus (E’ = ~5 GPa) than the neat polymer microprobes (E’ = ~2 GPa) and could sustain higher loads (~17 mN), facilitating penetration through the pia mater and insertion into the cerebral cortex of a rat. In contrast, the neat polymer microprobes mechanically failed under lower loads (~7 mN) before they were capable of inserting into cortical tissue. Further, we demonstrated the material’s ability to morph while in the rat cortex to more closely match the mechanical properties of the cortical tissue. Nanocomposite microprobes that were implanted into the rat cortex for up to 8 weeks demonstrated increased cell density at the microelectrode-tissue interface and a lack of tissue necrosis or excessive gliosis. This body of work introduces our nanocomposite-based microprobes as adaptive substrates for intracortical microelectrodes and potentially other biomedical applications. PMID:21654037

Study of the photovoltaic effect in thin film barium titanate

NASA Technical Reports Server (NTRS)

Grannemann, W. W.; Dharmadhikari, V. S.

1982-01-01

The basic mechanism associated with the photovoltaic phenomena observed in the R.F. sputtered BaTiO3/silicon system is presented. Series of measurements of short circuit photocurrents and open circuit photovoltage were made. The composition depth profiles and the interface characteristics of the BaTiO3/silicon system were investigated for a better understanding of the electronic properties. A Scanning Auger Microprobe combined with ion in depth profiling were used.

Boron Carbide Aluminum Cermets for External Pressure Housing Applications

DTIC Science & Technology

1992-09-01

CHEMISTRY AND MICROSTRUCTURES OF THE B4C/Al SYSTEM ......................................... 4 3.2 MECHANICAL PROPERTIES OF B4C/AI COMPOSITES ....... 10...TABLES 1. Phase chemistry of B4C/A1 composites as a function of baking temperature (by stereology) .................. ...... 10 2. Summary of the...diffractometer using CuKo radiation and a scan rate of 2° per minute. The chemistry of all phases was determined from electron microprobe analysis of

Standard design for National Ignition Facility x-ray streak and framing cameras.

PubMed

Kimbrough, J R; Bell, P M; Bradley, D K; Holder, J P; Kalantar, D K; MacPhee, A G; Telford, S

2010-10-01

The x-ray streak camera and x-ray framing camera for the National Ignition Facility were redesigned to improve electromagnetic pulse hardening, protect high voltage circuits from pressure transients, and maximize the use of common parts and operational software. Both instruments use the same PC104 based controller, interface, power supply, charge coupled device camera, protective hermetically sealed housing, and mechanical interfaces. Communication is over fiber optics with identical facility hardware for both instruments. Each has three triggers that can be either fiber optic or coax. High voltage protection consists of a vacuum sensor to enable the high voltage and pulsed microchannel plate phosphor voltage. In the streak camera, the high voltage is removed after the sweep. Both rely on the hardened aluminum box and a custom power supply to reduce electromagnetic pulse/electromagnetic interference (EMP/EMI) getting into the electronics. In addition, the streak camera has an EMP/EMI shield enclosing the front of the streak tube.

Frequencies of the Edge-Magnetoplasmon Excitations in Gated Quantum Hall Edges

NASA Astrophysics Data System (ADS)

Endo, Akira; Koike, Keita; Katsumoto, Shingo; Iye, Yasuhiro

2018-06-01

We have investigated microwave transmission through the edge of quantum Hall systems by employing a coplanar waveguide (CPW) fabricated on the surface of a GaAs/AlGaAs two-dimensional electron gas (2DEG) wafer. An edge is introduced to the slot region of the CPW by applying a negative bias Vg to the central electrode (CE) and depleting the 2DEG below the CE. We observe peaks attributable to the excitation of edge magnetoplasmons (EMP) at a fundamental frequency f0 and at its harmonics if0 (i = 2,3, \\ldots ). The frequency f0 increases with decreasing Vg, indicating that EMP propagates with higher velocity for more negative Vg. The dependence of f0 on Vg is interpreted in terms of the variation in the distance between the edge state and the CE, which alters the velocity by varying the capacitive coupling between them. The peaks are observed to continue, albeit with less clarity, up to the regions of Vg where 2DEG still remains below the CE.

Impact of an emergency medicine pharmacist on antibiotic dosing adjustment.

PubMed

DeWitt, Kyle M; Weiss, Steven J; Rankin, Shannon; Ernst, Amy; Sarangarm, Preeyaporn

2016-06-01

Overall medication-related errors in the emergency department (ED) are 13.5 times more likely to occur in the absence of an emergency medicine pharmacist (EMP). Although the effectiveness of pharmacist-driven renal dosing adjustment has been studied in the intensive care unit, data are lacking in the ED setting. The aim of our study was to evaluate the appropriateness of antibiotic dosing when an EMP is physically present in the ED compared to when absent. This was a retrospective cohort study of patients treated in a level I trauma center with 75 adult and 12 pediatric beds and an annual census of 90000 patients. The study period was from March 1 to September 30, 2014. An EMP was physically present in the ED from 11:00 to 01:30 and absent from 01:31 to 10:59. Male and female patients 18years and older were considered for inclusion if cefazolin, cefepime, ciprofloxacin, piperacillin-tazobactam, or vancomycin was ordered. The primary outcome was the composite rate of correct antibiotic dose and frequency. Statistics included a multivariable logistic regression using age, sex, presence of EMP, and creatinine clearance as independent predictors of correct antibiotic use. A total 210 cases were randomly chosen for evaluation, half during times when EMPs were present and half when they were absent. There were 130 males (62%) with an overall mean age of 54±18years. Overall, 178 (85%) of 210 of the antibiotic orders were appropriate, with 95% appropriate when an EMP was present compared to 74% when an EMP was absent (odds ratio, 6.9; 95% confidence interval, 2.5-18.8). In a logistic regression model, antibiotic appropriateness was independently associated with the presence of the EMP and creatinine clearance. Antibiotics that require renal and/or weight dosing adjustment are 6.5 times more likely to be appropriate in the ED when an EMP is present. Prevalence of antibiotic dosing error is related to both the presence of EMPs and the degree of renal impairment. Copyright © 2016 Elsevier Inc. All rights reserved.

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

Ice, G.E.; Barbee, T.; Bionta, R.

The increasing availability of synchrotron x-ray sources has stimulated the development of advanced hard x-ray (E{>=}5 keV) microprobes. New x-ray optics have been demonstrated which show promise for achieving intense submicron hard x-ray probes. These probes will be used for extraordinary elemental detection by x-ray fluorescence/absorption and for microdiffraction to identify phase and strain. The inherent elemental and crystallographic sensitivity of an x-ray microprobe and its inherently nondestructive and penetrating nature makes the development of an advanced hard x-ray microprobe an important national goal. In this workshop state-of-the-art hard x-ray microprobe optics were described and future directions were discussed. Genemore » Ice, Oak Ridge National Laboratory (ORNL), presented an overview of the current status of hard x-ray microprobe optics and described the use of crystal spectrometers to improve minimum detectable limits in fluorescent microprobe experiments. Al Thompson, Lawrence Berkeley Laboratory (LBL), described work at the Center for X-ray Optics to develop a hard x-ray microprobe based on Kirkpatrick-Baez (KB) optics. Al Thompson also showed the results of some experimental measurements with their KB optics. Malcolm Howells presented a method for bending elliptical mirrors and Troy Barbee commented on the use of graded d spacings to achieve highest efficiency in KB multilayer microfocusing. Richard Bionta, Lawrence Livermore National Laboratory (LLNL), described the development of the first hard x-ray zone plates and future promise of so called {open_quotes}jelly roll{close_quotes} or sputter slice zone plates. Wenbing Yun, Argonne National Laboratory (ANL), described characterization of jelly roll and lithographically produced zone plates and described the application of zone plates to focus extremely narrow bandwidths by nuclear resonance. This report summarizes the presentations of the workshop subgroup on hard x-ray microprobes.« less

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

Reusch, L. M., E-mail: lmmcguire@wisc.edu; Den Hartog, D. J.; Goetz, J.

The two-color soft x-ray (SXR) tomography diagnostic on the Madison Symmetric Torus is capable of making electron temperature measurements via the double-filter technique; however, there has been a 15% systematic discrepancy between the SXR double-filter (SXR{sub DF}) temperature and Thomson scattering (TS) temperature. Here we discuss calibration of the Be filters used in the SXR{sub DF} measurement using empirical measurements of the transmission function versus energy at the BESSY II electron storage ring, electron microprobe analysis of filter contaminants, and measurement of the effective density. The calibration does not account for the TS and SXR{sub DF} discrepancy, and evidence frommore » experiments indicates that this discrepancy is due to physics missing from the SXR{sub DF} analysis rather than instrumentation effects.« less

MORPH-I (Ver 1.0) a software package for the analysis of scanning electron micrograph (binary formatted) images for the assessment of the fractal dimension of enclosed pore surfaces

USGS Publications Warehouse

Mossotti, Victor G.; Eldeeb, A. Raouf; Oscarson, Robert

1998-01-01

MORPH-I is a set of C-language computer programs for the IBM PC and compatible minicomputers. The programs in MORPH-I are used for the fractal analysis of scanning electron microscope and electron microprobe images of pore profiles exposed in cross-section. The program isolates and traces the cross-sectional profiles of exposed pores and computes the Richardson fractal dimension for each pore. Other programs in the set provide for image calibration, display, and statistical analysis of the computed dimensions for highly complex porous materials. Requirements: IBM PC or compatible; minimum 640 K RAM; mathcoprocessor; SVGA graphics board providing mode 103 display.

C-reactive protein induces release of both endothelial microparticles and circulating endothelial cells in vitro and in vivo: further evidence of endothelial dysfunction.

PubMed

Devaraj, Sridevi; Kumaresan, Pappanaicken R; Jialal, Ishwarlal

2011-12-01

Inflammation is pivotal in atherosclerosis. A key early event in atherosclerosis is endothelial dysfunction. C-reactive protein (CRP), the prototypic marker of inflammation in humans, is a risk marker for cardiovascular disease, and there is mounting evidence to support its role in atherothrombosis. CRP has been shown to promote endothelial dysfunction both in vitro and in vivo. Emerging biomarkers of endothelial dysfunction include circulating endothelial cells (CECs) and endothelial microparticles (EMPs). However, there is a paucity of data examining the effect of CRP on CEC and EMP production in vitro and in vivo. In this report, we treated human aortic endothelial cells (HAECs) with increasing concentrations of CRP (0-50 μg/mL) or boiled CRP. We counted CECs and EMPs by flow cytometry. Although CRP treatment resulted in a significant increase in release of both CECs and EMPs, boiled CRP failed to have an effect. Pretreatment of HAECs with sepiapterin or diethylenetriamine NONOate, both of which preserve nitric oxide (NO), resulted in attenuation of CRP's effects on CECs and EMPs. CD32 and CD64 blocking antibodies but not CD16 antibody or lectin-like oxidized LDL receptor 1 small interfering RNA (LOX-1 siRNA) prevented CRP-induced production of CECs and EMPs. Furthermore, delivery of human CRP to Wistar rats compared with human serum albumin resulted in significantly increased CECs and EMPs, corroborating the in vitro findings. We provide novel data that CRP, via NO deficiency, promotes endothelial dysfunction by inducing release of CECs and EMPs, which are biomarkers of endothelial dysfunction.

The solubility and site preference of Fe3+ in Li7−3xFexLa3Zr2O12 garnets

PubMed Central

Rettenwander, D.; Geiger, C.A.; Tribus, M.; Tropper, P.; Wagner, R.; Tippelt, G.; Lottermoser, W.; Amthauer, G.

2015-01-01

A series of Fe3+-bearing Li7La3Zr2O12 (LLZO) garnets was synthesized using solid-state synthesis methods. The synthetic products were characterized compositionally using electron microprobe analysis and inductively coupled plasma optical emission spectroscopy (ICP-OES) and structurally using X-ray powder diffraction and 57Fe Mössbauer spectroscopy. A maximum of about 0.25 Fe3+ pfu could be incorporated in Li7−3xFexLa3Zr2O12 garnet solid solutions. At Fe3+ concentrations lower than about 0.16 pfu, both tetragonal and cubic garnets were obtained in the synthesis experiments. X-ray powder diffraction analysis showed only a garnet phase for syntheses with starting materials having intended Fe3+ contents lower than 0.52 Fe3+ pfu. Back-scattered electron images made with an electron microprobe also showed no phase other than garnet for these compositions. The lattice parameter, a0, for all solid-solution garnets is similar with a value of a0≈12.98 Å regardless of the amount of Fe3+. 57Fe Mössbauer spectroscopic measurements indicate the presence of poorly- or nano-crystalline FeLaO3 in syntheses with Fe3+ contents greater than 0.16 Fe3+ pfu. The composition of different phase pure Li7−3xFexLa3Zr2O12 garnets, as determined by electron microprobe (Fe, La, Zr) and ICP-OES (Li) measurements, give Li6.89Fe0.03La3.05Zr2.01O12, Li6.66Fe0.06La3.06Zr2.01O12, Li6.54Fe0.12La3.01Zr1.98O12, and Li6.19Fe0.19La3.02Zr2.04O12. The 57Fe Mössbauer spectrum of cubic Li6.54Fe0.12La3.01Zr1.98O12 garnet indicates that most Fe3+ occurs at the special crystallographic 24d position, which is the standard tetrahedrally coordinated site in garnet. Fe3+ in smaller amounts occurs at a general 96h site, which is only present for certain Li-oxide garnets, and in Li6.54Fe0.12La3.01Zr1.98O12 this Fe3+ has a distorted 4-fold coordination. PMID:26435549

Strategies, Protections and Mitigations for Electric Grid from Electromagnetic Pulse Effects

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

Foster, Rita Ann; Frickey, Steven Jay

2016-01-01

The mission of DOE’s Office of Electricity Delivery and Energy Reliability (OE) is to lead national efforts to modernize the electricity delivery system, enhance the security and reliability of America’s energy infrastructure and facilitate recovery from disruptions to the energy supply. One of the threats OE is concerned about is a high-altitude electro-magnetic pulse (HEMP) from a nuclear explosion and eletro-magnetic pulse (EMP) or E1 pulse can be generated by EMP weapons. DOE-OE provides federal leadership and technical guidance in addressing electric grid issues. The Idaho National Laboratory (INL) was chosen to conduct the EMP study for DOE-OE due tomore » its capabilities and experience in setting up EMP experiments on the electric grid and conducting vulnerability assessments and developing innovative technology to increase infrastructure resiliency. This report identifies known impacts to EMP threats, known mitigations and effectiveness of mitigations, potential cost of mitigation, areas for government and private partnerships in protecting the electric grid to EMP, and identifying gaps in our knowledge and protection strategies.« less

A review of mortality associated with elongate mineral particle (EMP) exposure in occupational epidemiology studies of gold, talc, and taconite mining.

PubMed

Mandel, Jeffrey H; Alexander, Bruce H; Ramachandran, Gurumurthy

2016-12-01

Mining of gold, taconite, and talc may involve exposure to elongate mineral particles (EMP). The involved EMPs are typically non-asbestiform, include dimensions that regulatory definitions exclude, and have been less studied. A review of the literature was undertaken for this exposure and occupational epidemiological studies that occur in gold, talc, and taconite mining. Quantitative EMP exposure information in these industries is incomplete. However, there are consistent findings of pneumoconiosis in each of these types of mining. A recent case-control study suggests a possible association between this exposure and mesothelioma. Lung cancer is inconsistently reported in these industries and is an unlikely outcome of non-asbestiform EMP exposure. There is evidence of cardiovascular mortality excess across all of these types of mining. Non-malignant respiratory disease and cardiovascular mortality have been consistently increased in these industries. Further investigation, including additional insights for the role of non-asbestiform EMP, is warranted. Am. J. Ind. Med. 59:1047-1060, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Underground Data Acquisition and Telemetry System

DTIC Science & Technology

1977-02-28

modulation is achieved in the circuit containing Q5, Ul, U2, Q6, and triac Q7, an RCA 40526. The function of the modulator is to switch the capacitor bank...approximately balance the charge current between the four battery strings. The ac-coupled Triac circuit is designed to provide additional EMP protection...I 4-9 CH * .* -.... ...... .. .. .. 0 :4 4-1 Each wafer, Figure 4.2-5, within an electronics module subassembly consists of a circuit

Annual Conference on Nuclear and Space Radiation Effects, 21st, Colorado Springs, CO, July 23-25, 1984, Proceedings

NASA Technical Reports Server (NTRS)

Winokur, P. S. (Editor)

1984-01-01

Radiation effects on electronic systems and devices (particularly spacecraft systems) are examined with attention given to such topics as radiation transport, energy deposition, and charge collection; single-event phenomena; basic mechanisms of radiation effects in structures and materials; and EMP phenomena. Also considered are radiation effects in integrated circuits, spacecraft charging and space radiation effects, hardness assurance for devices and systems, and SGEMP/IEMP phenomena.

Electrostatic Discharge (ESD) Susceptibility of Electronic Devices

DTIC Science & Technology

1983-01-01

determined by knowing the thermal environment in which the component is to operate. However, ESD is not that predictable . It is considered a random... predicted where a part may experience an ESD pulse during usage? (3) What effect does stressing a device with different models have on its propensity for...relatively low ESO threshold voltages (i.e., < 7000 volts) tend to be consistently high compared with their predicted level using EMP data. But at

Layer dependence of the superconducting transition temperature of HgBa2Can-1 CunO2 n+2+ δ

NASA Astrophysics Data System (ADS)

Scott, B. A.; Suard, E. Y.; Tsuei, C. C.; Mitzi, D. B.; McGuire, T. R.; Chen, B.-H.; Walker, D.

1994-09-01

High-pressure methods have been used to synthesize multiphase compositions in the Hg12{ n-1} n homologous series. The phase assemblages were examined by optical, electron diffraction and X-ray diffraction techniques, and their stoichiometries verified by electron microprobe. Transport and magnetic susceptibility measurements were combined with the results of the phase analysis to establish superconducting transition temperatures for both as-prepared and O 2- or Ar-annealed materials. It was found that the transition temperature peaks at Tc = 134 K for n = 3 and then decreases abruptly for n>4, reaching Tc<90 K for n⪖7.

Raman spectroscopy as a tool to characterize heterogenite (CoO·OH) (Katanga Province, Democratic Republic of Congo)

NASA Astrophysics Data System (ADS)

Burlet, C.; Vanbrabant, Y.; Goethals, H.; Thys, T.; Dupin, L.

2011-10-01

Natural heterogenite (CoO·OH) samples were studied by Raman microspectroscopy, electronic microprobe and Electronic BackScattered Diffraction (EBSD). Raw samples and polished sections were made from 10 mines covering the Katanga copperbelt (Katanga Province, Democratic Republic of Congo). Four typical Raman responses have been obtained leading to investigate the laser-induced dehydroxylation of heterogenite into a Co-spinel structure. The results are also compared with EBSD patterns from oven heated heterogenite samples. A close relationship was established between the chemical substitutions of Co by mainly Cu, Ni, Mn and Al and their impact on the mineral Raman response.

[Effect of electromagnetic pulse irradiation on mice reproduction].

PubMed

Wang, Shui-ming; Wang, De-wen; Peng, Rui-yun; Chen, Hao-yu; Gao, Ya-bing; Cao, Xiao-zhe; Cui, Xue-mei; Zhao, Mei-lan

2003-10-01

To evaluate the effect of electromagnetic pulse (EMP) irradiation on mice reproduction. Female/male Kunming mice, 6 - 8 weeks old, prior to mating, or female after pregnancy were treated with whole body irradiation by 6 x 10(4) V/m electromagnetic pulse (EMP) for five times. The pregnant mice were killed on the 18th days, and teratological markers were analysed. EMP irradiation caused no significant changes in most of female organ weight and organ/body weight ratio. But it caused significant shortening in tail length of live foetus in the female mice before conception (prior to mating) or after pregnancy (P < 0.05), and obvious decrease in male offspring ratio (0.85 +/- 0.09 vs 1.09 +/- 0.17, P < 0.05). The male offspring ratio also significantly decreased (0.76 +/- 0.18 vs 1.09 +/- 0.17, P < 0.01) after male mice irradiated by EMP. The tail length of live foetus was shortened and male offspring sex ratio was increased after both male and female mice were irradiated by EMP. EMP irradiation also caused a significantly higher fetal death rate than normal control (P < 0.05). The embryo absorption rate was increased after irradiation except that was decreased in male mice. EMP irradiation has effect on pregnancy and offspring development in both male and female mice before mating and in female mice after pregnancy.

Occurrence of Emerging Micropollutants in Water Systems in Gauteng, Mpumalanga, and North West Provinces, South Africa.

PubMed

Wanda, Elijah M M; Nyoni, Hlengilizwe; Mamba, Bhekie B; Msagati, Titus A M

2017-01-13

The ubiquitous occurrence of emerging micropollutants (EMPs) in water is an issue of growing environmental-health concern worldwide. However, there remains a paucity of data regarding their levels and occurrence in water. This study determined the occurrence of EMPs namely: carbamazepine (CBZ), galaxolide (HHCB), caffeine (CAF), tonalide (AHTN), 4-nonylphenol (NP), and bisphenol A (BPA) in water from Gauteng, Mpumalanga, and North West provinces, South Africa using comprehensive two-dimensional gas chromatography coupled to high resolution time-of-flight mass spectrometry (GCxGC-HRTOFMS). Kruskal-Wallis test and ANOVA were performed to determine temporal variations in occurrence of the EMPs. Principal component analysis (PCA) and Surfer Golden Graphics software for surface mapping were used to determine spatial variations in levels and occurrence of the EMPs. The mean levels ranged from 11.22 ± 18.8 ng/L for CAF to 158.49 ± 662 ng/L for HHCB. There was no evidence of statistically significant temporal variations in occurrence of EMPs in water. Nevertheless, their levels and occurrence vary spatially and are a function of two principal components (PCs, PC1 and PC2) which controlled 89.99% of the variance. BPA was the most widely distributed EMP, which was present in 62% of the water samples. The detected EMPs pose ecotoxicological risks in water samples, especially those from Mpumalanga province.

Occurrence of Emerging Micropollutants in Water Systems in Gauteng, Mpumalanga, and North West Provinces, South Africa

PubMed Central

Wanda, Elijah M. M.; Nyoni, Hlengilizwe; Mamba, Bhekie B.; Msagati, Titus A. M.

2017-01-01

The ubiquitous occurrence of emerging micropollutants (EMPs) in water is an issue of growing environmental-health concern worldwide. However, there remains a paucity of data regarding their levels and occurrence in water. This study determined the occurrence of EMPs namely: carbamazepine (CBZ), galaxolide (HHCB), caffeine (CAF), tonalide (AHTN), 4-nonylphenol (NP), and bisphenol A (BPA) in water from Gauteng, Mpumalanga, and North West provinces, South Africa using comprehensive two-dimensional gas chromatography coupled to high resolution time-of-flight mass spectrometry (GCxGC-HRTOFMS). Kruskal-Wallis test and ANOVA were performed to determine temporal variations in occurrence of the EMPs. Principal component analysis (PCA) and Surfer Golden Graphics software for surface mapping were used to determine spatial variations in levels and occurrence of the EMPs. The mean levels ranged from 11.22 ± 18.8 ng/L for CAF to 158.49 ± 662 ng/L for HHCB. There was no evidence of statistically significant temporal variations in occurrence of EMPs in water. Nevertheless, their levels and occurrence vary spatially and are a function of two principal components (PCs, PC1 and PC2) which controlled 89.99% of the variance. BPA was the most widely distributed EMP, which was present in 62% of the water samples. The detected EMPs pose ecotoxicological risks in water samples, especially those from Mpumalanga province. PMID:28098799

Disrupting Androgen Receptor Signaling Induces Snail-Mediated Epithelial-Mesenchymal Plasticity in Prostate Cancer.

PubMed

Miao, Lu; Yang, Lin; Li, Rui; Rodrigues, Daniel N; Crespo, Mateus; Hsieh, Jer-Tsong; Tilley, Wayne D; de Bono, Johann; Selth, Luke A; Raj, Ganesh V

2017-06-01

Epithelial-to-mesenchymal plasticity (EMP) has been linked to metastasis, stemness, and drug resistance. In prostate cancer, EMP has been associated with both suppression and activation of the androgen receptor (AR) signaling. Here we investigated the effect of the potent AR antagonist enzalutamide on EMP in multiple preclinical models of prostate cancer and patient tissues. Enzalutamide treatment significantly enhanced the expression of EMP drivers (ZEB1, ZEB2, Snail, Twist, and FOXC2) and mesenchymal markers (N-cadherin, fibronectin, and vimentin) in prostate cancer cells, enhanced prostate cancer cell migration, and induced prostate cancer transformation to a spindle, fibroblast-like morphology. Enzalutamide-induced EMP required concomitant suppression of AR signaling and activation of the EMP-promoting transcription factor Snail, as evidenced by both knockdown and overexpression studies. Supporting these findings, AR signaling and Snail expression were inversely correlated in C4-2 xenografts, patient-derived castration-resistant metastases, and clinical samples. For the first time, we elucidate a mechanism explaining the inverse relationship between AR and Snail. Specifically, we found that AR directly repressed SNAI1 gene expression by binding to specific AR-responsive elements within the SNAI1 promoter. Collectively, our findings demonstrate that de-repression of Snail and induction of EMP is an adaptive response to enzalutamide with implications for therapy resistance. Cancer Res; 77(11); 3101-12. ©2017 AACR . ©2017 American Association for Cancer Research.

Evaluation of Pharmacist Impact on Culture Review Process for Patients Discharged From the Emergency Department.

PubMed

Santiago, Ruben D; Bazan, Jose A; Brown, Nicole V; Adkins, Eric J; Shirk, Mary Beth

2016-10-01

Background: Accurate and timely review of microbiological test results is a core component of antimicrobial stewardship. There is documented success of these programs in the inpatient setting; however, emergency department (ED) patients are typically not included in these initiatives. Objectives: To assess the impact of an emergency medicine pharmacist (EMP)-facilitated review process of positive microbiological test results from patients discharged from the ED as measured by time to positive result review and number of indicated interventions completed. Methods: This was a retrospective study that compared EMP-facilitated to ED charge nurse (CN)-facilitated physician review of randomly selected positive microbiological test results. Groups were compared concurrently within the time frame of July 1, 2012 through December 31, 2012. Results: One hundred seventy-eight positive microbiological test results were included (EMP, n = 91; CN, n = 87). The median (IQR) time to initial review was 3 (1.0-6.3) hours for the EMP and 2 (0.3-5.5) hours for the CN group ( p = .35). Four percent (1/25) of indicated interventions were not completed in the EMP group versus 47% (14/30) in the CN group ( p = .0004). Conclusion: An EMP was significantly less likely to miss an intervention when indicated with no difference in time to review of positive microbiological results. These findings support the role of the EMP in antimicrobial stewardship in the ED.

Stakeholder perceptions of Environmental Management Plans as an environmental protection tool for major developments in the UK

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

Bennett, Sophie; Kemp, Simon; Hudson, Malcolm D., E-mail: mdh@soton.ac.uk

Insufficient implementation and the lack of legislative requirements for follow-up measures following the approval of projects are consistently highlighted as major shortcomings of Environmental Impact Assessment (EIA). Although adopted over 15 years ago by the World Bank, Environmental Management Plans (EMPs) were only semi-formalised in the UK in 2008 and arguably provide a continuous link or ‘bridge’ between the EIA process pre-consent and an Environmental Management System (EMS) post-consent. Drawing on twenty-one semi-structured interviews with stakeholders and thematic analysis of their responses, and a broad-scale practitioner survey, this study aimed to assess the effectiveness of EMPs as an environmental protectionmore » tool across the project lifecycle for major developments. The findings revealed a mixed picture of EMP effectiveness in practice, with EMPs only partially fulfilling a bridging role between EIA and EMS. There is no ‘gold standard’ terminology for EMPs, all having slightly different uses, thus presenting different focuses to different stakeholders and further enhancing variation in practice. For many stakeholders, the effectiveness was simply not known, due to the lack of communication and follow-up that still exists. EMP–EMS linkages were shown to be effective from the developer's perspective when a single organisation has involvement across all project phases, though weaknesses occur when multiple parties are involved. Among other stakeholders, knowledge varied significantly; whilst some were in agreement that the linkages worked, many were unaware of the connections and thought of them as two quite separate tools. Stakeholders advocated for the need to make EMPs a legal requirement; for improved communication between stakeholders during EMP implementation and increased documentation of project outcomes; and for EMPs to be consistently written by environmental professionals. Furthermore, weak links in the current process may be improved by providing detailed guidance for organisations on the potential for EMP–EMS linkages, with the additional aim of encouraging stakeholders to broaden their current specialist knowledge on environmental protection tools. - Highlights: • We assessed the effectiveness of Environmental Management Plans (EMPs) for major developments, focusing on delivery of mitigation and monitoring. • EIA and Environmental Management Systems (EMS) post-consent are weakly linked. • The use of EMPs varies significantly in practise, partly due to the range of terminology used. • Linkages are hampered by poor communication and follow-up • More detailed guidance on how EMPs can successfully link with EMS is required.« less

Racial differences in tumor necrosis factor-α-induced endothelial microparticles and interleukin-6 production

PubMed Central

Brown, Michael D; Feairheller, Deborah L; Thakkar, Sunny; Veerabhadrappa, Praveen; Park, Joon-Young

2011-01-01

African Americans (AA) tend to have heightened systemic inflammation and endothelial dysfunction. Endothelial microparticles (EMP) are released from activated/apoptotic endothelial cells (EC) when stimulated by inflammation. The purpose of our study was to assess EMP responses to inflammatory cytokine (TNF-α) and antioxidant (superoxide dismutase, SOD) conditions in human umbilical vein ECs (HUVECs) obtained from AA and Caucasians. EMPs were measured under four conditions: control (basal), TNF-α, SOD, and TNF-α + SOD. Culture supernatant was collected for EMP analysis by flow cytometry and IL-6 assay by ELISA. IL-6 protein expression was assessed by Western blot. AA HUVECs had greater EMP levels under the TNF-α condition compared to the Caucasian HUVECs (6.8 ± 1.1 vs 4.7% ± 0.4%, P = 0.04). The EMP level increased by 89% from basal levels in the AA HUVECs under the TNF-α condition (P = 0.01) compared to an 8% increase in the Caucasian HUVECs (P = 0.70). Compared to the EMP level under the TNF-α condition, the EMP level in the AA HUVECs was lower under the SOD only condition (2.9% ± 0.3%, P = 0.005) and under the TNF-α + SOD condition (2.1% ± 0.4%, P = 0.001). Basal IL-6 concentrations were 56.1 ± 8.8 pg/mL/μg in the AA and 30.9 ± 14.9 pg/mL/μg in the Caucasian HUVECs (P = 0.17), while basal IL-6 protein expression was significantly greater (P < 0.05) in the AA HUVECs. These preliminary observational results suggest that AA HUVECs may be more susceptible to the injurious effects of the proinflammatory cytokine, TNF-α. PMID:21966220

Electromagnetic pulse exposure induces overexpression of beta amyloid protein in rats.

PubMed

Jiang, Da-peng; Li, Jing; Zhang, Jie; Xu, Sheng-long; Kuang, Fang; Lang, Hai-yang; Wang, Ya-feng; An, Guang-zhou; Li, Jin-hui; Guo, Guo-zhen

2013-04-01

With the developing and widely used electromagnetic field (EMF) technology, more and more studies are focusing on the relationship between EMF and Alzheimer's disease (AD). Electromagnetic pulse (EMP) is one type of widely used EMF. This study aimed to clarify whether EMP exposure could induce cognitive and memory impairment, thus finding a possible relationship between EMP and AD. Forty healthy male Sprague Dawley rats were randomly divided into four groups. Animals, respectively, received 100, 1000, and 10,000 pulses EMP (field strength 50 kV/m, repetition rate 100 Hz) exposure and sham exposure when 2 months old. Monthly Morris water maze (MWM) was used to test the changes of cognitive and memory ability. Superoxide dismutase (SOD) activity and glutathione (GSH) content were used as oxidative stress indexes. Expressions of some types of Alzheimer's disease-related proteins were also detected. After exposure, EMP exposure caused clear cognitive and memory impairment compared with sham exposure group (p <0.05). Determination of oxidation indexes showed decreased SOD activity and GSH content in exposure groups compared with sham group. Immunohistochemical (IHC) staining showed increased beta amyloid protein (Aβ) in EMP exposure groups compared with sham group. Western blot experiments showed increased expressions of Aβ oligomer and beta amyloid protein precursor (APP) in EMP exposure groups. Increased expression of microtubule-associated protein 1 light chain 3-II (LC3-II) was also found. The present results showed that EMP exposure can cause long-term impairment in impaired cognition and memory of rats, resulting in AD-like symptoms. This may be induced by enhancing oxidative stress and is related to autophagy dysfunction. Copyright © 2013 IMSS. Published by Elsevier Inc. All rights reserved.

A Plasmodium falciparum PHIST protein binds the virulence factor PfEMP1 and comigrates to knobs on the host cell surface

PubMed Central

Oberli, Alexander; Slater, Leanne M.; Cutts, Erin; Brand, Françoise; Mundwiler-Pachlatko, Esther; Rusch, Sebastian; Masik, Martin F. G.; Erat, Michèle C.; Beck, Hans-Peter; Vakonakis, Ioannis

2014-01-01

Uniquely among malaria parasites, Plasmodium falciparum-infected erythrocytes (iRBCs) develop membrane protrusions, known as knobs, where the parasite adhesion receptor P. falciparum erythrocyte membrane protein 1 (PfEMP1) clusters. Knob formation and the associated iRBC adherence to host endothelium are directly linked to the severity of malaria and are functional manifestations of protein export from the parasite to the iRBC. A family of exported proteins featuring Plasmodium helical interspersed subtelomeric (PHIST) domains has attracted attention, with members being implicated in host-parasite protein interactions and differentially regulated in severe disease and among parasite isolates. Here, we show that PHIST member PFE1605w binds the PfEMP1 intracellular segment directly with Kd = 5 ± 0.6 μM, comigrates with PfEMP1 during export, and locates in knobs. PHIST variants that do not locate in knobs (MAL8P1.4) or bind PfEMP1 30 times more weakly (PFI1780w) used as controls did not display the same pattern. We resolved the first crystallographic structure of a PHIST protein and derived a partial model of the PHIST-PfEMP1 interaction from nuclear magnetic resonance. We propose that PFE1605w reinforces the PfEMP1-cytoskeletal connection in knobs and discuss the possible role of PHIST proteins as interaction hubs in the parasite exportome.—Oberli, A., Slater, L. M., Cutts, E., Brand, F., Mundwiler-Pachlatko, E., Rusch, S., Masik, M. F. G., Erat, M. C., Beck, H.-P., Vakonakis, I. A Plasmodium falciparum PHIST protein binds the virulence factor PfEMP1 and comigrates to knobs on the host cell surface. PMID:24983468

A Survey of Graduates of Combined Emergency Medicine-Pediatrics Residency Programs: An Update.

PubMed

Strobel, Ashley M; Chasm, Rose M; Woolridge, Dale P

2016-10-01

In 1998, emergency medicine-pediatrics (EM-PEDS) graduates were no longer eligible for the pediatric emergency medicine (PEM) sub-board certification examination. There is a paucity of guidance regarding the various training options for medical students who are interested in PEM. We sought to to determine attitudes and personal satisfaction of graduates from EM-PEDS combined training programs. We surveyed 71 graduates from three EM-PEDS residences in the United States. All respondents consider their combined training to be an asset when seeking a job, 92% find it to be an asset to their career, and 88% think it provided added flexibility to job searches. The most commonly reported shortcoming was their ineligibility for the PEM sub-board certification. The lack of this designation was perceived to be a detriment to securing academic positions in dedicated children's hospitals. When surveyed regarding which training offers the better skill set for the practice of PEM, 90% (44/49) stated combined EM-PEDS training. When asked which training track gives them the better professional advancement in PEM, 52% (23/44) chose combined EM-PEDS residency, 27% (12/44) chose a pediatrics residency followed by a PEM fellowship, and 25% (11/44) chose an EM residency then a PEM fellowship. No EM-PEDS respondents considered PEM fellowship training after the completion of the dual training program. EM-PEDS graduates found combined training to be an asset in their career. They felt that it provided flexibility in job searches, and that it was ideal training for the skill set required for the practice of PEM. EM-PEDS graduates' practices varied, including mixed settings, free-standing children's hospitals, and community emergency departments. Copyright © 2016 Elsevier Inc. All rights reserved.

Long-term electromagnetic pulse exposure induces Abeta deposition and cognitive dysfunction through oxidative stress and overexpression of APP and BACE1.

PubMed

Jiang, Da-Peng; Li, Jin-Hui; Zhang, Jie; Xu, Sheng-Long; Kuang, Fang; Lang, Hai-Yang; Wang, Ya-Feng; An, Guang-Zhou; Li, Jing; Guo, Guo-Zhen

2016-07-01

A progressively expanded literature has been devoted in the past years to the noxious or beneficial effects of electromagnetic field (EMF) to Alzheimer׳s disease (AD). This study concerns the relationship between electromagnetic pulse (EMP) exposure and the occurrence of AD in rats and the underlying mechanisms, focusing on the role of oxidative stress (OS). 55 healthy male Sprague Dawley (SD) rats were used and received continuous exposure for 8 months. Morris water maze (MWM) test was conducted to test the ability of cognitive and memory. The level of OS was detected by superoxide dismutase (SOD) activity and glutathione (GSH) content. We found that long-term EMP exposure induced cognitive damage in rats. The content of β-amyloid (Aβ) protein in hippocampus was increased after long-term EMP exposure. OS of hippocampal neuron was detected. Western blotting and immunohistochemistry (IHC) assay showed that the content of Aβ protein and its oligomers in EMP-exposed rats were higher than that of sham-exposed rats. The content of Beta Site App Cleaving Enzyme (BACE1) and microtubule-associated protein 1 light chain 3-II (LC3-II) in EMP-exposed rats hippocampus were also higher than that of sham-exposed rats. SOD activity and GSH content in EMP-exposed rats were lower than sham-exposed rats (p<0.05). Several mechanisms were proposed based on EMP exposure-induced OS, including increased amyloid precursor protein (APP) aberrant cleavage. Although further study is needed, the present results suggest that long-term EMP exposure is harmful to cognitive ability in rats and could induce AD-like pathological manifestation. Copyright © 2016 Elsevier B.V. All rights reserved.

Microparticles released by vascular endothelial cells increase hypoxia inducible factor expression in human proximal tubular HK-2 cells.

PubMed

Fernandez-Martínez, Ana Belen; Torija, Ana Valdehita; Carracedo, Julia; Ramirez, Rafael; de Lucio-Cazaña, Francisco Javier

2014-08-01

Microparticles are produced by vesiculation of the cell plasma membrane and serve as vectors of cell-to-cell communication. Co-culture experiments have shown that hypoxia-inducible factor-α (HIF-α)-regulated-genes are up-regulated in human renal proximal tubular HK-2 cells by endothelial cell factors which might be transported inside endothelial microparticles (EMP). Here we aimed to study in HK-2 cells the effect of EMP, produced by activated endothelial cells, on HIF-α and HIF-α-regulated vascular endothelial growth factor-A (VEGF-A). EMP, at a concentration much lower than that found in plasma, increased the expression of HIF-α/VEGF-A in a COX-2/EP2 receptor dependent manner. Since the EMP/cells ratio was ∼1/1000, we hypothesized that paracrine mediators produced by HK-2 cells amplified the initial signal. This hypothesis was confirmed by two facts which also suggested that the mediators were conveyed by particles released by HK-2 cells: (i) HIF-α was up-regulated in HK-2 cells treated with the pellet obtained from the conditioned medium of the EMP-treated HK-2 cells. (ii) In transwell experiments, EMP-treated cells increased the expression of HIF-α in untreated HK-2 cells. Interestingly, we detected these cells, particles that were released by EMP-treated HK-2 cells. Depending on the pathological context, activation of HIF-α and VEGF-A signaling in renal tissue/cells may have either beneficial or harmful effects. Therefore, our results suggest that their presence in the urinary space of EMP produced by activated endothelial cells may influence the outcome of a number of renal diseases. Copyright © 2014 Elsevier Ltd. All rights reserved.

Mercury Cadmium Telluride Sputtering Research.

DTIC Science & Technology

1982-08-28

originally designed for 5.7cm rather than 12.7cu diameter targets. A similar target made from poly- crystalline (Hg.8 Cd.2)Te material, which is difficult to...required 3 stainless steel pieces per dit, but provded a loM thamrl idauce for the diemspated taret power. The details of the design re given in...analyzed: 2) WDX detects and measures only one element at a time thereby ensuring better accuracy; 3) Since WDX electron microprobe is especially designed

Hot-phonon generation in THz quantum cascade lasers

NASA Astrophysics Data System (ADS)

Spagnolo, V.; Vitiello, M. S.; Scamarcio, G.; Williams, B. S.; Kumar, S.; Hu, Q.; Reno, J. L.

2007-12-01

Observation of non-equilibrium optical phonons population associated with electron transport in THz quantum cascade lasers is reported. The phonon occupation number was measured by using a combination of micro-probe photoluminescence and Stokes/Anti-Stokes Raman spectroscopy. Energy balance analysis allows us to estimate the phonon relaxation rate, that superlinearly increases with the electrical power in the range 1.5 W - 1.95 W, above laser threshold. This observation suggests the occurrence of stimulated emission of optical phonons.

Genesis of highland basalt breccias - A view from 66095

NASA Technical Reports Server (NTRS)

Garrison, J. R., Jr.; Taylor, L. A.

1980-01-01

Electron microprobe and defocused beam analyses of the lunar highland breccia sample 66095 show it consists of a fine-grained subophitic matrix containing a variety of mineral and lithic clasts, such as intergranular and cataclastic ANT, shocked and unshocked plagioclase, and basalts. Consideration of the chemistries of both matrix and clasts provides a basis for a qualitative three-component mixing model consisting of an ANT plutonic complex, a Fra Mauro basalt, and minor meteoric material.

Spectral and temporal characteristics of target current and electromagnetic pulse induced by nanosecond laser ablation

NASA Astrophysics Data System (ADS)

Krása, J.; De Marco, M.; Cikhardt, J.; Pfeifer, M.; Velyhan, A.; Klír, D.; Řezáč, K.; Limpouch, J.; Krouský, E.; Dostál, J.; Ullschmied, J.; Dudžák, R.

2017-06-01

The current balancing the target charging and the emission of transient electromagnetic pulses (EMP) driven by the interaction of a focused 1.315 μm iodine 300 ps PALS laser with metallic and plastic targets were measured with the use of inductive probes. It is experimentally proven that the duration of return target currents and EMPs is much longer than the duration of laser-target interaction. The laser-produced plasma is active after the laser-target interaction. During this phase, the target acts as a virtual cathode and the plasma-target interface expands. A double exponential function is used in order to obtain the temporal characteristics of EMP. The rise time of EMPs fluctuates in the range up to a few tens of nanoseconds. Frequency spectra of EMP and target currents are modified by resonant frequencies of the interaction chamber.

1-Ethyl-1-methyl piperidinium bis(trifluoromethanesulfonyl)imide as a co-solvent in Li-ion batteries

NASA Astrophysics Data System (ADS)

Kim, Ketack; Cho, Young-Hyun; Shin, Heon-Cheol

2013-03-01

1-Ethyl-1-methyl piperidinium bis(trifluoromethanesulfonyl)imide (EMP-TFSI) is an ionic liquid with a melting temperature of 85 °C. Although it is a solid salt, it shows good miscibility with carbonate solvents, which allows EMP-TFSI to be used as a co-solvent in these systems. Ethylene carbonate is another solid co-solvent used in Li-ion batteries. Due to its smaller cationic size, EMP-TFSI provides better conductivity as a co-solvent than 1-methyl-1-propyl piperidinium bis(trifluoromethanesulfonyl)imide (MPP-TFSI), which is the smallest room-temperature piperidinium liquid salt known. In cells with 50 wt% IL and 50 wt% carbonate electrolyte, an EMP-TFSI mixed electrolyte performs better than an MPP-TFSI mixed electrolyte. Additionally, the discharge capacity values obtained from rate capability tests carried out with mixed EMP-TFSI are as good as those conducted with a pure carbonate electrolyte.

Apollo guidance, navigation and control: Guidance system operations plans for manned LM earth orbital and lunar missions using Program COLOSSUS 3. Section 7: Erasable memory programs

NASA Technical Reports Server (NTRS)

Hamilton, M. H.

1972-01-01

Erasable-memory programs (EMPs) designed for the guidance computers used in the command (CMC) and lunar modules (LGC) are described. CMC programs are designated COLOSSUS 3, and the associated EMPs are identified by a three-digit number beginning with 5. LGC programs are designated LUMINARY 1E, and the associated EMPs are identified, with one exception, by a three-digit number beginning with 1. The exception is EMP 99. The EMPs vary in complexity from a simple flagbit setting to a long and intricate logical structure. They all, however, cause the computer to behave in a way not intended in the original design of the programs; they accomplish this off-nominal behavior by some alteration of erasable memory to interface with existing fixed-memory programs to effect a desired result.

Electromagnetic radiations from laser interaction with gas-filled Hohlraum

NASA Astrophysics Data System (ADS)

Yang, Ming; Yang, Yongmei; Li, Tingshuai; Yi, Tao; Wang, Chuanke; Liu, Shenye; Jiang, Shaoen; Ding, Yongkun

2018-01-01

The emission of intensive electromagnetic pulse (EMP) due to laser-target interactions at the ShenGuang-III laser facility has been evaluated by probes. EMP signals measured using the small discone antennas demonstrated two variation trends including a bilateral oscillation wave and a unilateral oscillation wave. The new trend of unilateral oscillation could be attributed to the hohlraum structure and low-Z gas in the hohlraum. The EMP waveform showed multiple peaks when the gas-filled hohlraum was shot by the high-power laser. Comparing the EMP signals with the verification of stimulated Raman scattering energy and hard x-ray energy spectrum, we found that the intensity of EMP signals decreased with the increase of the hohlraum size. The current results are expected to offer preliminary information to study physical processes on laser injecting gas-filled hohlraums in the National Ignition Facility implementation.

EMP Interaction: Principles, Techniques and Reference Data (A Compleat concatenation of Technology from the EMP Interaction Notes). EMP Interaction 2-1

DTIC Science & Technology

1980-12-01

staff of Dikewood, Santa Monica, no. only has contributed a large amount of material to this document, but also proofread the typescript . In...assistance and skills in the preparation of the entire typescript . Dikewood Industries, Inc. K.S.H. LEE Santa Monica, California September, 1979 xJ

Healthcare vulnerabilities to electromagnetic pulse.

PubMed

Ross, Lenard H; Mihelic, F Matthew

2008-01-01

The U.S. healthcare system is particularly vulnerable to the effects of electromagnetic pulse (EMP) attack because of the system's technological sophistication, but while national defense planners prepare for the considerable threat that EMP poses, there has been little or no recognition of this threat within the US healthcare community, and neither has there been any significant healthcare planning to deal with such an eventuality. Recognition of the risk presented by EMP, and advance institution of appropriate strategies to mitigate its effects on the healthcare system, could enable the preservation of much of that system's function in the face of EMP-related disruptions, and will greatly further all-hazards disaster preparations.

Endothelial microparticles and vascular parameters in subjects with and without arterial hypertension and coronary artery disease.

PubMed

Sansone, Roberto; Baaken, Maximilian; Horn, Patrick; Schuler, Dominik; Westenfeld, Ralf; Amabile, Nicolas; Kelm, Malte; Heiss, Christian

2018-08-01

Endothelial microparticles (EMPs) are markers of endothelial injury and activation. The role of EMPs in arterial hypertension is not well understood and EMPs are increased both in arterial hypertension and coronary artery disease (CAD). The data presented here show EMPs as defined by CD31 + /41 - , CD62e + , and CD144 + surface markers and vascular hemodynamic parameters including office and central blood pressure, heart rate, aortic augmentation index, pulse wave velocity, flow-mediated dilation, nitroglycerin-mediated dilation, brachial artery diameter, hyperemic wall shear stress, and laser Doppler perfusion of the cutaneous microcirculation of normotensives and hypertensives with and without CAD.

sae is essential for expression of the staphylococcal adhesins Eap and Emp.

PubMed

Harraghy, Niamh; Kormanec, Jan; Wolz, Christiane; Homerova, Dagmar; Goerke, Christiane; Ohlsen, Knut; Qazi, Saara; Hill, Philip; Herrmann, Mathias

2005-06-01

Eap and Emp are two Staphylococcus aureus adhesins initially described as extracellular matrix binding proteins. Eap has since emerged as being important in adherence to and invasion of eukaryotic cells, as well as being described as an immunomodulator and virulence factor in chronic infections. This paper describes the mapping of the transcription start point of the eap and emp promoters. Moreover, using reporter-gene assays and real-time PCR in defined regulatory mutants, environmental conditions and global regulators affecting expression of eap and emp were investigated. Marked differences were found in expression of eap and emp between strain Newman and the 8325 derivatives SH1000 and 8325-4. Moreover, both genes were repressed in the presence of glucose. Analysis of expression of both genes in various regulatory mutants revealed that sarA and agr were involved in their regulation, but the data suggested that there were additional regulators of both genes. In a sae mutant, expression of both genes was severely repressed. sae expression was also reduced in the presence of glucose, suggesting that repression of eap and emp in glucose-containing medium may, in part, be a consequence of a decrease in expression of sae.

Mechanisms involved in the blood-testis barrier increased permeability induced by EMP.

PubMed

Wang, Xiao-Wu; Ding, Gui-Rong; Shi, Chang-Hong; Zeng, Li-Hua; Liu, Jun-Ye; Li, Jing; Zhao, Tao; Chen, Yong-Bin; Guo, Guo-Zhen

2010-09-30

The blood-testis barrier (BTB) plays an important role in male reproductive system. Lots of environmental stimulations can increase the permeability of BTB and then result in antisperm antibody (AsAb) generation, which is a key step in male immune infertility. Here we reported the results of male mice exposed to electromagnetic pulse (EMP) by measuring the expression of tight-junction-associated proteins (ZO-1 and Occludin), vimentin microfilaments, and transforming growth factor-beta (TGF-beta3) as well as AsAb level in serum. Male BALB/c mice were sham exposed or exposed to EMP at two different intensities (200kV/m and 400kV/m) for 200 pulses. The testes were collected at different time points after EMP exposure. Immunofluorescence histocytochemistry, western blotting, laser confocal microscopy and RT-PCR were used in this study. Compared with sham group, the expression of ZO-1 and TGF-beta3 significantly decreased accompanied with unevenly stained vimentin microfilaments and increased serum AsAb levels in EMP-exposed mice. These results suggest a potential BTB injury and immune infertility in male mice exposed to a certain intensity of EMP. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

Influence of sex on the number of circulating endothelial microparticles and microRNA expression in middle-aged adults.

PubMed

Bammert, Tyler D; Hijmans, Jamie G; Kavlich, Philip J; Lincenberg, Grace M; Reiakvam, Whitney R; Fay, Ryan T; Greiner, Jared J; Stauffer, Brian L; DeSouza, Christopher A

2017-08-01

What is the central question of this study? Are there sex-related differences in the number of circulating endothelial microparticles (EMPs) and microparticle microRNA expression in middle-aged adult humans? What is the main finding and its importance? Although the numbers of circulating endothelial microparticles do not differ between middle-aged men and women, there are sex-related differences in the expression of miR-125a in activation-derived EMPs and miR-34a in apoptosis-derived EMPs. Differences in circulating endothelial microparticle microRNA content may provide new insight into the sex-related disparity in the risk and prevalence of vascular disease in middle-aged adults. The aims of this study were to determine: (i) whether circulating concentrations of endothelial microparticles (EMPs) differ in middle-aged men compared with women; and (ii) whether there are sex-related differences in microRNA expression in EMPs. Peripheral blood was collected from 30 sedentary adults: 15 men (56 ± 6 years old) and 15 women (56 ± 5 years old). Endothelial microparticles were defined by markers of activation (CD62e + ) or apoptosis (CD31 + /CD42b - ) by flow cytometry. Expression of microRNA (miR-34a, 92a, 125a and 126) in activation- and apoptosis-derived EMPs was measured by RT-PCR. Circulating activation- (33 ± 31 versus 39 ± 35 microparticles μl -1 ) and apoptosis-derived EMPs (49 ± 54 versus 42 ± 43 microparticles μl -1 ) were not significantly different between men and women. Expression of miR-125a (2.23 ± 2.01 versus 6.95 ± 3.99 a.u.) was lower (∼215%; P < 0.05) in activation-derived EMPs, whereas expression of miR-34a (1.17 ± 1.43 versus 0.38 ± 0.35 a.u.) was higher (∼210%; P < 0.05) in apoptosis-derived EMPs from men compared with women. Expression of microRNA in circulating EMPs may provide new insight into sex-related differences in cardiovascular disease. © 2017 The Authors. Experimental Physiology © 2017 The Physiological Society.

SU-8 microprobe with microelectrodes for monitoring electrical impedance in living tissues.

PubMed

Tijero, M; Gabriel, G; Caro, J; Altuna, A; Hernández, R; Villa, R; Berganzo, J; Blanco, F J; Salido, R; Fernández, L J

2009-04-15

This paper presents a minimally invasive needle-shaped probe capable of monitoring the electrical impedance of living tissues. This microprobe consists of a 160 microm thick SU-8 substrate containing four planar platinum (Pt) microelectrodes. We design the probe to minimize damage to the surrounding tissue and to be stiff enough to be inserted in living tissues. The proposed batch fabrication process is low cost and low time consuming. The microelectrodes obtained with this process are strongly adhered to the SU-8 substrate and their impedance does not depend on frequency variation. In vitro experiments are compared with previously developed Si and SiC based microprobes and results suggest that it is preferable to use the SU-8 based microprobes due to their flexibility and low cost. The microprobe is assembled on a flexible printed circuit FPC with a conductive glue, packaged with epoxy and wired to the external instrumentation. This flexible probe is inserted into a rat kidney without fracturing and succeeds in demonstrating the ischemia monitoring.

Ion and laser microprobes applied to the measurement of corrosion produced hydrogen on a microscopic scale.

NASA Technical Reports Server (NTRS)

Gray, H. R.

1972-01-01

Use of an ion microprobe and a laser microprobe to measure concentrations of corrosion-produced hydrogen on a microscopic scale. Hydrogen concentrations of several thousand ppm were measured by both analytical techniques below corroded and fracture surfaces of hot salt stress corroded titanium alloy specimens. This extremely high concentration compares with only about 100 ppm hydrogen determined by standard vacuum fusion chemical analyses of bulk samples. Both the ion and laser microprobes were used to measure hydrogen concentration profiles in stepped intervals to substantial depths below the original corroded and fracture surfaces. For the ion microprobe, the area of local analysis was 22 microns in diameter and for the laser microprobe, the area of local analysis was about 300 microns in diameter. The segregation of hydrogen below fracture surfaces supports a previously proposed theory that corrosion-produced hydrogen is responsible for hot salt stress corrosion embrittlement and cracking of titanium alloys. These advanced analytical techniques suggest great potential for many areas of stress corrosion and hydrogen embrittlement research, quality control, and field inspection of corrosion problems. For example, it appears possible that a contour map of hydrogen distribution at notch roots and crack tips could be quantitatively determined. Such information would be useful in substantiating current theories of stress corrosion and hydrogen embrittlement.

Targeting epithelial-mesenchymal plasticity in cancer: clinical and preclinical advances in therapy and monitoring.

PubMed

Bhatia, Sugandha; Monkman, James; Toh, Alan Kie Leong; Nagaraj, Shivashankar H; Thompson, Erik W

2017-09-20

The concept of epithelial-mesenchymal plasticity (EMP), which describes the dynamic flux within the spectrum of phenotypic states that invasive carcinoma cells may reside, is being increasingly recognised for its role in cancer progression and therapy resistance. The myriad of events that are able to induce EMP, as well as the more recently characterised control loops, results in dynamic transitions of cancerous epithelial cells to more mesenchymal-like phenotypes through an epithelial-mesenchymal transition (EMT), as well as the reverse transition from mesenchymal phenotypes to an epithelial one. The significance of EMP, in its ability to drive local invasion, generate cancer stem cells and facilitate metastasis by the dissemination of circulating tumour cells (CTCs), highlights its importance as a targetable programme to combat cancer morbidity and mortality. The focus of this review is to consolidate the existing knowledge on the strategies currently in development to combat cancer progression via inhibition of specific facets of EMP. The prevalence of relapse due to therapy resistance and metastatic propensity that EMP endows should be considered when designing therapy regimes, and such therapies should synergise with existing chemotherapeutics to benefit efficacy. To further improve upon EMP-targeted therapies, it is imperative to devise monitoring strategies to assess the impact of such treatments on EMP-related phenomenon such as CTC burden, chemosensitivity/-resistance and micrometastasis in patients. © 2017 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

Report of the Commission to Assess the Threat to the United States from Electromagnetic Pulse (EMP) Attack: Critical National Infrastructures

DTIC Science & Technology

2008-04-01

consumers and electric utilities in Arizona and Southern California. Twelve people, including five children, died as a result of the explosion. The...Modern electronics, communications, pro- tection, control and computers have allowed the physical system to be utilized fully with ever smaller... margins for error. Therefore, a relatively modest upset to the system can cause functional collapse. As the system grows in complexity and interdependence

Electromagnetic Pulse Weapons as an Emergent Technology and Their Place on Battlefields of the Future

DTIC Science & Technology

2010-04-19

GPOILPS 10 1707; http://www.empcmmnission.org/docs/ A24 73- EMP Commission-7MB.pdf. Fitts, Richard E., and Robert W. Burton. 1980. The strategy of...London: Commonwealth Secretariat. Iannini, Robert E. 2004. Electronic gadgets for the evil genius. New York: McGraw-Hill, http://www .loc. gov I...Calif. 13000 Raymer St., North Hollywood 91605: Western Periodicals Co. Schilling, William R. 2002. Nontraditional warfare : Twenty-first-century

Fast probing of glucose and fructose in plant tissues via plasmonic affinity sandwich assay with molecularly-imprinted extraction microprobes.

PubMed

Muhammad, Pir; Liu, Jia; Xing, Rongrong; Wen, Yanrong; Wang, Yijia; Liu, Zhen

2017-12-01

Determination of specific target compounds in agriculture food and natural plant products is essential for many purposes; however, it is often challenging due to the complexity of the sample matrices. Herein we present a new approach called plasmonic affinity sandwich assay for the facile and rapid probing of glucose and fructose in plant tissues. The approach mainly relies on molecularly imprinted plasmonic extraction microprobes, which were prepared on gold-coated acupuncture needles via boronate affinity controllable oriented surface imprinting with the target monosaccharide as the template molecules. An extraction microprobe was inserted into plant tissues under investigation, which allowed for the specific extraction of glucose or fructose from the tissues. The glucose or fructose molecules extracted on the microprobe were labeled with boronic acid-functionalized Raman-active silver nanoparticles, and thus affinity sandwich complexes were formed on the microprobes. After excess Raman nanotags were washed away, the microprobe was subjected to Raman detection. Upon being irradiated with a laser beam, surface plasmon on the gold-coated microprobes was generated, which further produced plasmon-enhanced Raman scattering of the silver-based nanotags and thereby provided sensitive detection. Apple fruits, which contain abundant glucose and fructose, were used as a model of plant tissues. The approach exhibited high specificity, good sensitivity (limit of detection, 1 μg mL -1 ), and fast speed (the whole procedure required only 20 min). The spatial distribution profiles of glucose and fructose within an apple were investigated by the developed approach. Copyright © 2017 Elsevier B.V. All rights reserved.

Study on processing immiscible materials in zero gravity

NASA Technical Reports Server (NTRS)

Reger, J. L.; Mendelson, R. A.

1975-01-01

An experimental investigation was conducted to evaluate mixing immiscible metal combinations under several process conditions. Under one-gravity, these included thermal processing, thermal plus electromagnetic mixing, and thermal plus acoustic mixing. The same process methods were applied during free fall on the MSFC drop tower facility. The design is included of drop tower apparatus to provide the electromagnetic and acoustic mixing equipment, and a thermal model was prepared to design the specimen and cooling procedure. Materials systems studied were Ca-La, Cd-Ga and Al-Bi; evaluation of the processed samples included the morphology and electronic property measurements. The morphology was developed using optical and scanning electron microscopy and microprobe analyses. Electronic property characterization of the superconducting transition temperatures were made using an impedance change-tuned coil method.

Differential Impact of Acute High-Intensity Exercise on Circulating Endothelial Microparticles and Insulin Resistance between Overweight/Obese Males and Females

PubMed Central

Durrer, Cody; Robinson, Emily; Wan, Zhongxiao; Martinez, Nic; Hummel, Michelle L.; Jenkins, Nathan T.; Kilpatrick, Marcus W.; Little, Jonathan P.

2015-01-01

Background An acute bout of exercise can improve endothelial function and insulin sensitivity when measured on the day following exercise. Our aim was to compare acute high-intensity continuous exercise (HICE) to high-intensity interval exercise (HIIE) on circulating endothelial microparticles (EMPs) and insulin sensitivity in overweight/obese men and women. Methods Inactive males (BMI = 30 ± 3, 25 ± 6 yr, n = 6) and females (BMI = 28 ± 2, 21 ± 3 yr, n = 7) participated in three experimental trials in a randomized counterbalanced crossover design: 1) No exercise control (Control); 2) HICE (20 min cycling @ just above ventilatory threshold); 3) HIIE (10 X 1-min @ ∼90% peak aerobic power). Exercise conditions were matched for external work and diet was controlled post-exercise. Fasting blood samples were obtained ∼18 hr after each condition. CD62E+ and CD31+/CD42b- EMPs were assessed by flow cytometry and insulin resistance (IR) was estimated by homeostasis model assessment (HOMA-IR). Results There was a significant sex X exercise interaction for CD62E+ EMPs, CD31+/CD42b- EMPs, and HOMA-IR (all P<0.05). In males, both HICE and HIIE reduced EMPs compared to Control (P≤0.05). In females, HICE increased CD62E+ EMPs (P<0.05 vs. Control) whereas CD31+/CD42b- EMPs were unaltered by either exercise type. There was a significant increase in HOMA-IR in males but a decrease in females following HIIE compared to Control (P<0.05). Conclusions Overweight/obese males and females appear to respond differently to acute bouts of high-intensity exercise. A single session of HICE and HIIE reduced circulating EMPs measured on the morning following exercise in males but in females CD62E+ EMPs were increased following HICE. Next day HOMA-IR paradoxically increased in males but was reduced in females following HIIE. Future research is needed to investigate mechanisms responsible for potential differential responses between males and females. PMID:25710559

Non-destructive trace element microanalysis of as-received cometary nucleus samples using synchrotron x ray fluorescence

NASA Technical Reports Server (NTRS)

Sutton, S. R.

1989-01-01

The Synchrotron X ray Fluorescence (SXRF) microprobe at the National Synchrotron Light Source (NSLS), Brookhaven National Laboratory, will be an excellent instrument for non-destructive trace element analyses of cometary nucleus samples. Trace element analyses of as-received cometary nucleus material will also be possible with this technique. Bulk analysis of relatively volatile elements will be important in establishing comet formation conditions. However, as demonstrated for meteorites, microanalyses of individual phases in their petrographic context are crucial in defining the histories of particular components in unequilibrated specimens. Perhaps most informative in comparing cometary material with meteorites will be the halogens and trace metals. In-situ, high spatial resolution microanalyses will be essential in establishing host phases for these elements and identifying terrestrial (collection/processing) overprints. The present SXRF microprobe is a simple, yet powerful, instrument in which specimens are excited with filtered, continuum synchrotron radiation from a bending magnet on a 2.5 GeV electron storage ring. A refrigerated cell will be constructed to permit analyses at low temperatures. The cell will consist essentially of an air tight housing with a cold stage. Kapton windows will be used to allow the incident synchrotron beam to enter the cell and fluorescent x rays to exit it. The cell will be either under vacuum or continuous purge by ultrapure helium during analyses. Several other improvements of the NSLS microprobe will be made prior to the cometary nucleus sample return mission that will greatly enhance the sensitivity of the technique.

Gel shift analysis of the empA promoter region in Vibrio anguillarum.

PubMed

Denkin, Steven M; Sekaric, Pedja; Nelson, David R

2004-10-29

The induction of metalloprotease encoded by empA in Vibrio anguillarum occurs at high cell density in salmon intestinal mucus. Previously we have shown that there are significant differences in empA expression in two strains of V. anguillarum, M93Sm and NB10. It is hypothesized that differences in empA regulation are due to differences in binding of regulatory elements. Two strains of V. anguillarum, M93Sm and NB10, were examined and compared for the presence of DNA regulatory proteins that bind to and control the empA promoter region. Gel mobility shift assays, using a digoxigenin (DIG)-labeled oligomer containing a lux box-like element and the promoter for empA, were done to demonstrate the presence of a DNA-binding protein. Protein extracts from NB10 cells incubated in Luria Bertani broth + 2% NaCl (LB20), nine salts solution + 200 microg/ml mucus (NSSM), 3M (marine minimal medium), or NSS resulted in a gel mobility shift. No gel mobility shift was seen when protein extracts from either LB20- or NSSM-grown M93Sm cells were mixed with the DIG-labeled empA oligomer. The azocasein assay detected protease activity in all incubation conditions for NB10 culture supernatants. In contrast, protease activity was detected in M93Sm culture supernatants only when incubated in NSSM. Since the luxR homologue in V. anguillarum, vanT, has been cloned, sequenced, and shown to be required for protease activity, we wanted to determine if vanT mutants of NB10 exhibit the same gel shift observed in the wild-type. Site-directed mutagenesis was used to create vanT mutants in V. anguillarum M93Sm and NB10 to test whether VanT is involved with the gel mobility shift. Both vanT mutants, M02 and NB02, did not produce protease activity in any conditions. However, protein extracts from NB02 incubated in each condition still exhibited a gel shift when mixed with the DIG-labeled empA oligomer. The data demonstrate that protein extracts of V. anguillarum NB10 cells contain a protein that binds to a 50 bp oligomer containing the empA promoter-lux box-like region. NB10 cells express empA during stationary phase in all growth conditions. The DNA binding protein is not present in M93Sm extracts. M93Sm cells express protease activity only when incubated at high cell density in fish gastrointestinal mucus. The gel shift observed with NB10 cells is not due to VanT binding. The data also suggest that the DNA binding protein is responsible for the less restrictive expression of empA in NB10 compared to M93Sm.

Studies of Brazilian meteorites. XIV - Mineralogy, petrology, and chemistry of the Conquista, Minas Gerais, chondrite

NASA Technical Reports Server (NTRS)

Keil, K.; Kirchner, E.; Gomes, C. B.; Jarosewich, E.; Murta, R. L. L.

1978-01-01

The Conquista chondrite is described and classified as an H4. The mineral composition is reported. H-group classification is based on described microscopic, electron microprobe, and bulk chemical studies. The evidence for petrologic type 4 classification includes the pronounced well-developed chondritic texture; the slight compositional variations in constituent phases; the high Ca contents of pyroxene and the presence of pigeonite; glassy to microcrystalline interstitial material rich in alkalis and SiO2; and twinned low-Ca clinopyroxene.

Characterization of crust formation on a parent body of achondrites and the moon by pyroxene crystallography and chemistry

NASA Technical Reports Server (NTRS)

Takeda, H.; Miyamoto, M.; Ishii, T.; Reid, A. M.

1976-01-01

Single crystal X-ray diffraction and electron microprobe techniques were used to study lunar crustal pyroxenes in a cataclastic norite, a pyroxene-rich clast, and anorthosite lunar samples, and also in meteorites including diogenites, eucrites, and the Yamoto (1) howardite. The crystallographic and chemical characteristics of pyroxenes in these materials are compared and are discussed in terms of the lower stability limit of pigeonite. A mechanical mixing model of howardite is proposed.

Experimental verification of the shape of the excitation depth distribution function for AES

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

Tougaard, S.; Jablonski, A.; Institute of Physical Chemistry, Polish Academy of Sciences, ul. Kasprzaka 44/52, 01-224 Warsaw

2011-09-15

In the common formalism of AES, it is assumed that the in-depth distribution of ionizations is uniform. There are experimental indications that this assumption may not be true for certain primary electron energies and solids. The term ''excitation depth distribution function'' (EXDDF) has been introduced to describe the distribution of ionizations at energies used in AES. This function is conceptually equivalent to the Phi-rho-z function of electron microprobe analysis (EPMA). There are, however, experimental difficulties to determine this function in particular for energies below {approx} 10 keV. In the present paper, we investigate the possibility of determining the shape ofmore » the EXDDF from the background of inelastically scattered electrons on the low energy side of the Auger electron features in the electron energy spectra. The experimentally determined EXDDFs are compared with the EXDDFs determined from Monte Carlo simulations of electron trajectories in solids. It is found that this technique is useful for the experimental determination of the EXDDF function.« less

EMP/GMD Phase 0 Report, A Review of EMP Hazard Environments and Impacts

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

Rivera, Michael Kelly; Backhaus, Scott N.; Woodroffe, Jesse Richard

The purpose of this study is to determine methods to analyze the hazard environments, impacts, and consequences of different sources of electromagnetic pulse (EMP), including nuclear electromagnetic pulse (NEMP) and geomagnetic disturbance (GMD) on the U.S. electric power infrastructures and to use those methods to determine EMP and GMD events of concern. The study will be carried out in four phases, each of which will provide higher levels of analytic fidelity that focuses on those EMP/GMD sources and events that create significant consequences, or whose consequences are sufficiently uncertain, to require more in-depth study. This study will leverage the bestmore » experimental data; device, equipment and system models; and simulation tools currently available. This study focuses primarily on the bulk electric system (BES) including large generating stations, large power transformers, the transmission network, and transmission system protection. Electrical distribution systems may potentially be included, if warranted, after consideration of the consequences for the bulk power system.« less

[The effects of electromagnetic pulse on fluidity and lipid peroxidation of mitochondrial membrane].

PubMed

Wang, Changzhen; Cong, Jianbo; Xian, Hong; Cao, Xiaozhe; Sun, Cunpu; Wu, Ke

2002-08-01

To study the effects of intense electromagnetic pulse(EMP) on the biological effects of mitochondrial membrane. Rat liver mitochondrial suspension was exposed to EMP at 60 kV/m level. The changes of membrane lipid fluidity and membrane protein mobility were detected by ESR and spin label technique. Malondialdehyde(MDA) was detected by spectrophotometer. The mobility of membrane protein decreased significantly(P < 0.05). Correlation time (tau c) of control group was (0.501 +/- 0.077) x 10(-9)s, and tau c of EMP group was (0.594 +/- 0.049) x 10(-9)s, indicating that the mobility of protein was restricted. The fluidity of mitochondrial membrane increased significantly(P < 0.05) at the same time. Order parameter(S) of mitochondrial membrane lipid in control group was 0.63 +/- 0.01, while S of EMP group was 0.61 +/- 0.01(P < 0.05). MDA decreased significantly. The mobility and lipid peroxidation of mitochondrial membrane may be disturbed after EMP exposure.

EMP-induced alterations of tight junction protein expression and disruption of the blood-brain barrier.

PubMed

Ding, Gui-Rong; Qiu, Lian-Bo; Wang, Xiao-Wu; Li, Kang-Chu; Zhou, Yong-Chun; Zhou, Yan; Zhang, Jie; Zhou, Jia-Xing; Li, Yu-Rong; Guo, Guo-Zhen

2010-07-15

The blood-brain barrier (BBB) is critical to maintain cerebral homeostasis. In this study, we examined the effects of exposure to electromagnetic pulse (EMP) on the functional integrity of BBB and, on the localization and expression of tight junction (TJ) proteins (occludin and ZO-1) in rats. Animals were sham or whole-body exposed to EMP at 200 kV/m for 400 pulses. The permeability of BBB in rat cerebral cortex was examined by using Evans Blue (EB) and lanthanum nitrate as vascular tracers. The localization and expression of TJ proteins were assessed by western blot and immunofluorescence analysis, respectively. The data indicated that EMP exposure caused: (i) increased permeability of BBB, and (ii) altered localization as well as decreased levels of TJ protein ZO-1. These results suggested that the alteration of ZO-1 may play an important role in the disruption of tight junctions, which may lead to dysfunction of BBB after EMP exposure. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

Corrosion phenomena in electron, proton and synchrotron X-ray microprobe analysis of Roman glass from Qumran, Jordan

NASA Astrophysics Data System (ADS)

Janssens, K.; Aerts, A.; Vincze, L.; Adams, F.; Yang, C.; Utui, R.; Malmqvist, K.; Jones, K. W.; Radtke, M.; Garbe, S.; Lechtenberg, F.; Knöchel, A.; Wouters, H.

1996-04-01

A series of 89 glass fragments of Roman glass are studied using electron, proton and synchrotron radiation induced X-ray emission from microscopic areas on the sample surface. The glass originates from Qumran, Jordan and was buried for 1900 years. The weathering layers that result from the extended contact with ground water have been studied, next to the trace composition of the original glass of these pieces. The latter information indicates that at Qumran, large quantities of glass objects were being used in Ancient times. Cross-sectional profiles of the glass show a complex migration behaviour of various groups of major and trace elements.

Analyses of amphibole asbestiform fibers in municipal water supplies

PubMed Central

Nicholson, William J.

1974-01-01

Details are given of the techniques used in the analysis of asbestiform fibers in the water systems of Duluth, Minnesota and other cities. Photographic electron diffraction and electron microprobe analyses indicated that the concentration of verified amphibole mineral fibers ranged from 20 × 106 to 75 × 106 fibers/l. Approximately 50–60% of the fibers were in the cummingtonite-grunerite series and 20% were in the actinolite-tremolite series. About 5% were chemically identical with amosite. A wide variety of analytical techniques must be employed for unique identification of the mineral species present in water systems. ImagesFIGURE 1.FIGURE 2.FIGURE 3.FIGURE 4.FIGURE 5.FIGURE 6. PMID:4470931

Organic contamination analysis: High resolution mass spectrometric analysis of surface organics on selected areas of Surveyor 3

NASA Technical Reports Server (NTRS)

Simoneit, B. R.; Burlingame, A. L.

1972-01-01

The mirror and middle shroud were extracted for organics by washing the surfaces with solvents. The techniques are discussed. Ion microprobe analyses of the primarily atomic species are presented. The sources of the organic contaminants are: (1) hydrocarbons from lubricating oils and general terrestrial contamination, (2) dioctyl phthalate, probably from polyethylene bagging material (the plasticizer), (3) carboxylic acids from decomposition of grease and general terrestrial contamination, (4) silicones from sources such as lubricating oil, (5) outgassing of electronics and plasticizer, (6) vinyl alcohol and styrene copolymer, probably from electronic insulation, and (7) nitrogenous compounds from the lunar module and possibly Surveyor 3 engine exhaust.

EMP Vulnerabilities of Telecommunications Facilities and Their Relevance to EMP Protection Standards

DTIC Science & Technology

1980-06-01

capacitor must be capable of withstanding surges of two and one-half times the rated voltage with a rise time of the surge to half crest voltage of 4...n Executive Summary This report identifies and categorizes the reasons for High Altitude Electromagnetic Pulse (HEMP) vulnerability of terrestrial...for the design, installation and maintenance of telecommunication facilities. 1.1 Background High- altitude EMP (HEMP) vulnerabilities and effects

Recommended E3 HEMP Heave Electric Field Waveform for the Critical Infrastructures. Volume 2

DTIC Science & Technology

2017-07-31

OF THE COMMISSION TO ASSESS THE THREAT TO THE UNITED STATES FROM ELECTROMAGNETIC PULSE (EMP) ATTACK The cover photo depicts Fishbowl Starfish...Assess the Threat to the United States from Electromagnetic Pulse (EMP) Attack. The Commission was established by Congress in the FY2001 National...Department of Defense E electric field EMP electromagnetic pulse EPRI Electric Power Research Institute FERC Federal Energy Regulatory Commission GMD

Assessment and Mitigation of Electromagnetic Pulse (EMP) Impacts at Short-pulse Laser Facilities

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

Brown, Jr., C G; Bond, E; Clancy, T

2009-10-02

The National Ignition Facility (NIF) will be impacted by electromagnetic pulse (EMP) during normal long-pulse operation, but the largest impacts are expected during short-pulse operation utilizing the Advanced Radiographic Capability (ARC). Without mitigation these impacts could range from data corruption to hardware damage. We describe our EMP measurement systems on Titan and NIF and present some preliminary results and thoughts on mitigation.

Assessment and Mitigation of Electromagnetic Pulse (EMP) Impacts at Short-pulse Laser Facilities

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

Brown, Jr., C G; Bond, E; Clancy, T

2010-02-04

The National Ignition Facility (NIF) will be impacted by electromagnetic pulse (EMP) during normal long-pulse operation, but the largest impacts are expected during short-pulse operation utilizing the Advanced Radiographic Capability (ARC). Without mitigation these impacts could range from data corruption to hardware damage. We describe our EMP measurement systems on Titan and NIF and present some preliminary results and thoughts on mitigation.

Exploring the SDSS Dataset with Linked Scatter Plots: I. EMP, CEMP, and CV Stars

NASA Technical Reports Server (NTRS)

Carbon, Duane F.; Henze, Christopher; Nelson, Bron C.

2017-01-01

We present the results of a search for EMP, CEMP, and cataclysmic variable stars using a new exploration tool based on linked scatter plots (LSPs). Our approach is especially designed to work with very large spectrum data sets such as the SDSS, LAMOST, RAVE, and Gaia data sets and can be applied to stellar, galaxy, and quasar spectra. As a demonstration, we conduct a search for EMP, CEMP, and cataclysmic variable stars in the SDSS DR10 data set. We first created a 3326-dimensional phase space containing nearly 2 billion measures of the strengths of over 1600 spectral features in 569,738 SDSS stars. These measures capture essentially all the stellar atomic and molecular species visible at the resolution of SDSS spectra. We show how LSPs can be used to quickly isolate and examine interesting portions of this phase space. To illustrate, we use LSPs coupled with cuts in selected portions of phase space to extract EMP stars, C-rich EMP stars, and CV stars. We present identifications for 59 previously unrecognized candidate EMP stars and 11 previously unrecognized candidate CEMP stars. We also call attention to 2 candidate He II emission CV stars found by the LSP approach that have not yet been discussed in the literature.

CDC's Emergency Management Program activities - worldwide, 2003-2012.

PubMed

2013-09-06

In 2003, recognizing the increasing frequency and complexity of disease outbreaks and disasters and a greater risk for terrorism, CDC established the Emergency Operations Center (EOC), bringing together CDC staff members who respond to public health emergencies to enhance communication and coordination. To complement the physical EOC environment, CDC implemented the Incident Management System (IMS), a staffing structure and set of standard operational protocols and services to support and monitor CDC program-led responses to complex public health emergencies. The EOC and IMS are key components of CDC's Emergency Management Program (EMP), which applies emergency management principles to public health practice. To enumerate activities conducted by the EMP during 2003-2012, CDC analyzed data from daily reports and activity logs. The results of this analysis determined that, during 2003-2012, the EMP fully activated the EOC and IMS on 55 occasions to support responses to infectious disease outbreaks, natural disasters, national security events (e.g., conventions, presidential addresses, and international summits), mass gatherings (e.g., large sports and social events), and man-made disasters. On 109 other occasions, the EMP was used to support emergency responses that did not require full EOC activation, and the EMP also conducted 30 exercises and drills. This report provides an overview of those 194 EMP activities.

Exploring the SDSS Dataset with Linked Scatter Plots: I. EMP, CEMP, and CV Stars.

PubMed

Carbon, Duane F; Henze, Christopher; Nelson, Bron C

2017-02-01

We present the results of a search for EMP, CEMP, and cataclysmic variable stars using a new exploration tool based on linked scatter plots (LSPs). Our approach is especially designed to work with very large spectrum data sets such as the SDSS, LAMOST, RAVE, and Gaia data sets and can be applied to stellar, galaxy, and quasar spectra. As a demonstration, we conduct a search for EMP, CEMP, and cataclysmic variable stars in the SDSS DR10 data set. We first created a 3326-dimensional phase space containing nearly 2 billion measures of the strengths of over 1600 spectral features in 569,738 SDSS stars. These measures capture essentially all the stellar atomic and molecular species visible at the resolution of SDSS spectra. We show how LSPs can be used to quickly isolate and examine interesting portions of this phase space. To illustrate, we use LSPs coupled with cuts in selected portions of phase space to extract EMP stars, C-rich EMP stars, and CV stars. We present identifications for 59 previously unrecognized candidate EMP stars and 11 previously unrecognized candidate CEMP stars. We also call attention to 2 candidate He II emission CV stars found by the LSP approach that have not yet been discussed in the literature.

Exploring the SDSS Dataset with Linked Scatter Plots: I. EMP, CEMP, and CV Stars

PubMed Central

Carbon, Duane F.; Henze, Christopher; Nelson, Bron C.

2017-01-01

We present the results of a search for EMP, CEMP, and cataclysmic variable stars using a new exploration tool based on linked scatter plots (LSPs). Our approach is especially designed to work with very large spectrum data sets such as the SDSS, LAMOST, RAVE, and Gaia data sets and can be applied to stellar, galaxy, and quasar spectra. As a demonstration, we conduct a search for EMP, CEMP, and cataclysmic variable stars in the SDSS DR10 data set. We first created a 3326-dimensional phase space containing nearly 2 billion measures of the strengths of over 1600 spectral features in 569,738 SDSS stars. These measures capture essentially all the stellar atomic and molecular species visible at the resolution of SDSS spectra. We show how LSPs can be used to quickly isolate and examine interesting portions of this phase space. To illustrate, we use LSPs coupled with cuts in selected portions of phase space to extract EMP stars, C-rich EMP stars, and CV stars. We present identifications for 59 previously unrecognized candidate EMP stars and 11 previously unrecognized candidate CEMP stars. We also call attention to 2 candidate He II emission CV stars found by the LSP approach that have not yet been discussed in the literature. PMID:28684884

Iron-Regulated Biofilm Formation in Staphylococcus aureus Newman Requires ica and the Secreted Protein Emp▿

PubMed Central

Johnson, Miranda; Cockayne, Alan; Morrissey, Julie A.

2008-01-01

Staphylococcus aureus biofilm formation is induced in iron-restricted growth conditions in vitro. In this study, we showed that Emp and Eap play important roles in low-iron-induced biofilm formation of S. aureus Newman. Eap and Emp are secreted proteins which are non-covalently attached to the S. aureus cell surface and have previously been implicated in a number of aspects of S. aureus pathogenesis. We showed here that the transcription of these important virulence factors is induced by growth in low-iron medium, reflective of the in vivo environment. Our results show that iron regulation of Eap and Emp is Fur independent. However, Fur is required for full induction of eap and emp expression in low-iron conditions. In this study, we demonstrated that in addition to Fur, low-iron-induced biofilm formation requires Sae, Agr, and SarA. In iron-restricted growth conditions, Sae and Agr are essential for Emp and Eap expression and hence for biofilm formation, whereas SarA appears to have a less-significant role. We also showed that expression of the ica operon is required for biofilm formation in iron-restricted growth conditions. We demonstrated that in fact, ica is required for the expression of the important multifunctional virulence determinants eap and emp. PMID:18268030

Finishing broiler toms using an estradiol 17 beta implant together with a high energy-low protein final feed.

PubMed

Moran, E T; Etches, R J

1983-06-01

Wrolstad Small White toms were implanted with 10 mg of estradiol 17 beta monopalmitate (EMP) at 8 weeks of age. Common corn-soybean meal feeds were given through to 12 weeks, then one-half the birds from control and EMP groups received either an adequate (16% protein, 3166 kcal ME/kg) or high energy-low protein (HE-LP, 12%, 3373 kcal) feed to 14 weeks. No differences in weight gain and feed conversion occurred between EMP and control treatments at 12 weeks but at 14 weeks when the HE-LP diet had been fed the implanted birds performed better than controls. The HE-LP feed led to body weights and feed efficiencies below that of toms given adequate diet. In all cases, EMP elicited male secondary sex characteristics rather than feminization. Processing losses were increased with EMP and when the HE-LP feed had been given. Both treatments also improved finish assessment and were additive to the extent that a substantial increase in grade occurred. Effects on carcass composition, yield of commercial cuts, and cooking loss were small. Implantation, reduced meat yield percentage of breast and thigh. The increase in grade advantage from combining EMP with a feed that forced fat deposition more than compensated for the adverse effects.

Effects of electromagnetic pulse exposure on gelatinase of blood-brain barrier in vitro.

PubMed

Zhou, Yan; Qiu, Lian-Bo; An, Guang-Zhou; Zhou, Jia-Xing; Du, Le; Ma, Ya-Hong; Guo, Guo-Zhen; Ding, Gui-Rong

2017-01-01

The biological effects of electromagnetic pulse (EMP) on the brain have been focused on for years. It was reported that gelatinase played an important role in maintaining brain function through regulating permeability in the blood-brain barrier (BBB). To investigate the effects of EMP on gelatinase of BBB, an in vitro BBB model was established using primary cultured rat brain microvascular endothelial cells (BMVEC), astrocytes and half-contact culture of these cells in a transwell chamber. Cultured supernatant and cells were collected at different time points after exposure to EMP (peak intensity 400 kV/m, rise time 10 ns, pulse width 350 ns, 0.5 pps and 200 pulses). Protein levels of cellular gelatinase MMP-2 and MMP-9, and endogenous inhibitor TIMP-1 and TIMP-2 were detected by Western blot. The activity of gelatinase in culture supernatant was detected by gelatin zymography. It was found that compared with the sham-exposed group, the protein level of MMP-2 was significantly increased at 6 h (p < 0.05), and the protein level of its endogenous inhibitor TIMP-2 did not change after EMP exposure. In addition, the protein levels of MMP-9 and its endogenous inhibitor TIMP-1 did not change after EMP exposure. Gelatin zymography results showed that the activity of MMP-2 in the inner pool and the outer pool of the transwell chamber was significantly increased at 6 h after EMP exposure compared with that of the sham group. These results suggested that EMP exposure could affect the expression and activity of MMP-2 in the BBB model.

Differential diagnosis of acute rejection and chronic cyclosporine nephropathy after rat renal transplantation by detection of endothelial microparticles (EMP).

PubMed

Cui, Jiewei; Yang, Jing; Cao, Weike; Sun, Yi

2010-12-01

Endothelial microparticles (EMP) are small vesicles smaller than 1.0μm, released from endothelial cells (EC) during their activation and (or) apoptosis. The assay of the level of elevated EMP is a new approach to evaluate the dysfunction of endothelial cell. EMP can be classified into several types according to their membrane molecular, and the levels of various types of EMP may be different. As the most cost-effective immunodepressant, cyclosporine A (CsA) has been used widely in organ transplantation. But its dose is hard to control, under-medication may cause the acute rejection (AR) and overdose may cause chronic cyclosporine nephropathy (CCN). The cyclosporine A (CsA) caused CCN and the AR caused renal injury after renal transplantation are both vascular diseases related with endothelial dysfunction, and up to now, there is still no effective method to distinguish the two kinds of diseases. Owing to distinct pathogenesis of the two kinds of vascular diseases, the level of each type of EMP originated from vascular endothelial cells may be different. We hypothesize that maybe we can distinguish them by detecting the different levels of some types of EMP which is also related with vascular disease, and we propose to prove our hypothesis through animal experiment. If our hypothesis is proved, it will be more helpful for clinicians to adjust the dose of CsA promptly according to the differential diagnosis of the two kinds of diseases. Copyright © 2010 Elsevier Ltd. All rights reserved.

CD144+ endothelial microparticles as a marker of endothelial injury in neonatal ABO blood group incompatibility.

PubMed

Awad, Hisham A E; Tantawy, Azza A G; El-Farrash, Rania A; Ismail, Eman A; Youssif, Noha M

2014-04-01

ABO antigens are expressed on the surfaces of red blood cells and the vascular endothelium. We studied circulating endothelial microparticles (EMP) in ABO haemolytic disease of the newborn (ABO HDN) as a marker of endothelial activation to test a hypothesis of possible endothelial injury in neonates with ABO HDN, and its relation with the occurrence and severity of haemolysis. Forty-five neonates with ABO HDN were compared with 20 neonates with Rhesus incompatibility (Rh HDN; haemolytic controls) and 20 healthy neonates with matched mother and infant blood groups (healthy controls). Laboratory investigations were done for markers of haemolysis and von Willebrand factor antigen (vWF Ag). EMP (CD144(+)) levels were measured before and after therapy (exchange transfusion and/or phototherapy). vWF Ag and pre-therapy EMP levels were higher in infants with ABO HDN or Rh HDN than in healthy controls, and were significantly higher in babies with ABO HDN than in those with Rh HDN (p<0.05). In ABO HDN, pre-therapy EMP levels were higher in patients with severe hyperbilirubinaemia than in those with mild and moderate disease or those with Rh HDN (p<0.001). Post-therapy EMP levels were lower than pre-therapy levels in both the ABO HDN and Rh HDN groups; however, the decline in EMP levels was particularly evident after exchange transfusion in ABO neonates with severe hyperbilirubinaemia (p<0.001). Multiple regression analysis revealed that the concentrations of haemoglobin, lactate dehydrogenase and indirect bilirubin were independently correlated with pre-therapy EMP levels in ABO HDN. Elevated EMP levels in ABO HDN may reflect an IgG-mediated endothelial injury parallel to the IgG-mediated erythrocyte destruction and could serve as a surrogate marker of vascular dysfunction and disease severity in neonates with this condition.

[Alteration of Microparticle Levels in Early Complications During Hematopoietic Stem Cell Transplantation].

PubMed

Zhou, Li-Li; Han, Yue; Zhu, Qian; Zhao, Shi-Xiang; Wang, Qian; Zhu, Ming-Qing; Dai, Lan; Shen, Wen-Hong; Wu, De-Pei

2015-12-01

To investigate the alteration of microparticles (MP) in the recipients following hematopoietic stem cell transplantation (HSCT) and its significance, and to search the early diagnostic indicators of thrombotic complications after transplantation. According to the occurrence of transplantation-associated complications, 94 allo-HSCT patients were divided into 4 groups: thrombotic group (VOD n = 7, TMA n = 2), acute graft-versus-host disease (aGVHD) group (n = 27), infection group (n = 41) and non-complication group (n = 17). Alterations of serum concentration of tissue factor positive microparticles (TF(+) MP) and endothelial microparticles (EMP) were analyzed by flow cytometry during the process of conditioning treatment and the early stage after transplantation. The relation of these 2 kinds of MP with complications was analysed. (1) The levels of TF(+) MP and EMP of patients undogoing allo-HSCT before conditioning treatment were obviously higher than those in normal controls, and showed some elevation during different times, but there was no significant statistical difference. Although the levels of TF(+) MP and EMP at the end of conditioning treatment were some higher than those before conditioning treatment, but there was no statistical difference between them. (2)The levels of TF(+) MP and EMP in thrombotic group were obviously higher than those in aGVHD group and infection group (P < 0.05). (3)The levels of TF(+) MP and EMP in thrombotic group at different times were significant differences from those in other groups (P < 0.05), and the levels of TF(+) MP and EMP were no significant difference from those in non-complication group. The increase of the TF(+) MP and EMP levels may be associated with occurrence of thrombosis after transplantation, indicating occurrence of the thrombotic complications, like hepatic vein occulusive disease (HVOD). The dynamically monitoring levels of TF(+) MP and EMP contributes to early discovery of thrombotic complications.

Convalescent Plasmodium falciparum-specific seroreactivity does not correlate with paediatric malaria severity or Plasmodium antigen exposure.

PubMed

Kessler, Anne; Campo, Joseph J; Harawa, Visopo; Mandala, Wilson L; Rogerson, Stephen J; Mowrey, Wenzhu B; Seydel, Karl B; Kim, Kami

2018-04-25

Antibody immunity is thought to be essential to prevent severe Plasmodium falciparum infection, but the exact correlates of protection are unknown. Over time, children in endemic areas acquire non-sterile immunity to malaria that correlates with development of antibodies to merozoite invasion proteins and parasite proteins expressed on the surface of infected erythrocytes. A 1000 feature P. falciparum 3D7 protein microarray was used to compare P. falciparum-specific seroreactivity during acute infection and 30 days after infection in 23 children with uncomplicated malaria (UM) and 25 children with retinopathy-positive cerebral malaria (CM). All children had broad P. falciparum antibody reactivity during acute disease. IgM reactivity decreased and IgG reactivity increased in convalescence. Antibody reactivity to CIDR domains of "virulent" PfEMP1 proteins was low with robust reactivity to the highly conserved, intracellular ATS domain of PfEMP1 in both groups. Although children with UM and CM differed markedly in parasite burden and PfEMP1 exposure during acute disease, neither acute nor convalescent PfEMP1 seroreactivity differed between groups. Greater seroprevalence to a conserved Group A-associated ICAM binding extracellular domain was observed relative to linked extracellular CIDRα1 domains in both case groups. Pooled immune IgG from Malawian adults revealed greater reactivity to PfEMP1 than observed in children. Children with uncomplicated and cerebral malaria have similar breadth and magnitude of P. falciparum antibody reactivity. The utility of protein microarrays to measure serological recognition of polymorphic PfEMP1 antigens needs to be studied further, but the study findings support the hypothesis that conserved domains of PfEMP1 are more prominent targets of cross reactive antibodies than variable domains in children with symptomatic malaria. Protein microarrays represent an additional tool to identify cross-reactive Plasmodium antigens including PfEMP1 domains that can be investigated as strain-transcendent vaccine candidates.

High glucose derived endothelial microparticles increase active caspase-3 and reduce microRNA-Let-7a expression in endothelial cells.

PubMed

Bammert, Tyler D; Hijmans, Jamie G; Reiakvam, Whitney R; Levy, Ma'ayan V; Brewster, Lillian M; Goldthwaite, Zoe A; Greiner, Jared J; Stockelman, Kelly A; DeSouza, Christopher A

2017-11-18

The experimental aim of this study was to determine the effects of high glucose-induced endothelial microparticles (EMPs) on endothelial cell susceptibility to apoptosis. Human umbilical vein endothelial cells (HUVECs) were cultured (3rd passage) and plated in 6-well plates at a density of 5.0 × 10 5  cells/condition. Cells were incubated with media containing 25 mM d-glucose (concentration representing a diabetic glycemic state) or 5 mM d-glucose (normoglycemic condition) for 48 h to generate EMPs. EMP identification (CD144 + expression) and concentration was determined by flow cytometry. HUVECs (3 × 10 6  cells/condition) were treated with EMPs generated from either the normal or high glucose conditions for 24 h. Intracellular concentration of active caspase-3 was determined by enzyme immunoassay. Cellular expression of miR-Let7a, an anti-apoptotic microRNA, was determined by RT-PCR using the ΔΔCT normalized to RNU6. High glucose-derived EMPs significantly increased both basal (1.5 ± 0.1 vs 1.0 ± 0.1 ng/mL) and staurosporine-stimulated (2.2 ± 0.2 vs 1.4 ± 0.1 ng/mL) active caspase-3 compared with normal glucose EMPs. Additionally, the expression of miR-Let-7a was markedly reduced (∼140%) by high glucose EMPs (0.43 ± 0.17 fold vs control). These results demonstrate that hyperglycemic-induced EMPs increase endothelial cell active caspase-3. This apoptotic effect may be mediated, at least in part, by a reduction in miR-Let-7a expression. Copyright © 2017 Elsevier Inc. All rights reserved.

Chromium in urban sediment particulates: an integrated micro-chemical and XANES study

NASA Astrophysics Data System (ADS)

Taylor, Kevin; Byrne, Patrick; Hudson-Edwards, Karen

2015-04-01

Chromium is generally common within the urban sediment cascade as a result of abundant industrial and transport-related sources. The risks that Cr-bearing particles pose to ecosystems and humans depend on the solid phase chemical speciation of Cr in the particles. In this study, we use bulk chemical digests, sequential chemical extraction analysis, electron microscopy, electron microprobe and microfocus XANES analysis to describe the solid-phase speciation of Cr in urban particulate matter from both aquatic sediment and road dust sediment (RDS) in Manchester, UK. Cr-bearing grains within RDS are predominantly iron oxide grains, commonly of goethite or haematite mineralogy, but Cr-bearing silicate glass grains are also present. Iron oxide glass grains most likely have sorbed Cr, and derive from the rusting of Cr-steel particles from vehicles. Electron microprobe analysis indicates concentrations of Cr up to 3200 μg/g in these grains, and XANES analysis indicates that Cr(III) is the dominant oxidation state, with some trace amounts of Cr(VI). Cr-bearing grains within aquatic sediments are dominated by alumino-silicate glass grains derived from industrial waste. These grains contain Cr-rich areas with up to 19% Cr2O3 and XANES analysis indicates that Cr is present as Cr(III). The dominance of Cr(III) in these urban particulate grains suggests limited bioavailability or toxicity. However, the presence within two markedly different grain types (iron oxides and silicate glasses) indicates that the long-term geochemical behaviour and environmental risk of RDS and the aquatic sediments studied are likely to be quite different. These findings highlight the importance of understanding sources of metal contaminants in urban environments and the geochemical processes that affect their transfer through the urban sediment cascade and the wider river basin.

Measurements of the quantitative lateral analytical resolution at evaporated aluminium and silver layers with the JEOL JXA-8530F FEG-EPMA

NASA Astrophysics Data System (ADS)

Berger, D.; Nissen, J.

2018-01-01

The studies in this paper are part of systematic investigations of the lateral analytical resolution of the field emission electron microprobe JEOL JXA-8530F. Hereby, the quantitative lateral resolution, which is achieved in practise, is in the focus of interest. The approach is to determine the minimum thickness of a metallic layer for which an accurate quantitative element analysis in cross-section is still possible. Previous measurements were accomplished at sputtered gold (Z = 79) layers, where a lateral resolution in the range of 140 to 170 nm was achieved at suitable parameters of the microprobe. To study the Z-dependence of the lateral resolution, now aluminium (Z = 13) resp. silver (Z = 47) layers with different thicknesses were generated by evaporation and prepared in cross-section subsequently by use of a focussed Ga-ion beam (FIB). Each layer was analysed quantitatively with different electron energies. The thinnest layer which can be resolved specifies the best lateral resolution. These measured values were compared on the one hand with Monte Carlo simulations and on the other hand with predictions from formulas from the literature. The measurements fit well to the simulated and calculated values, except the ones at the lowest primary electron energies with an overvoltage below ˜ 2. The reason for this discrepancy is not clear yet and has to be clarified by further investigations. The results apply for any microanalyser - even with energy-dispersive X-ray spectrometry (EDS) detection - if the probe diameters, which might deviate from those of the JEOL JXA-8530F, at suitable analysing parameters are considered.

Atmospheric electromagnetic pulse propagation effects from thick targets in a terawatt laser target chamber.

PubMed

Remo, John L; Adams, Richard G; Jones, Michael C

2007-08-20

Generation and effects of atmospherically propagated electromagnetic pulses (EMPs) initiated by photoelectrons ejected by the high density and temperature target surface plasmas from multiterawatt laser pulses are analyzed. These laser radiation pulse interactions can significantly increase noise levels, thereby obscuring data (sometimes totally) and may even damage sensitive probe and detection instrumentation. Noise effects from high energy density (approximately multiterawatt) laser pulses (approximately 300-400 ps pulse widths) interacting with thick approximately 1 mm) metallic and dielectric solid targets and dielectric-metallic powder mixtures are interpreted as transient resonance radiation associated with surface charge fluctuations on the target chamber that functions as a radiating antenna. Effective solutions that minimize atmospheric EMP effects on internal and proximate electronic and electro-optical equipment external to the system based on systematic measurements using Moebius loop antennas, interpretations of signal periodicities, and dissipation indicators determining transient noise origin characteristics from target emissions are described. Analytic models for the effect of target chamber resonances and associated noise current and temperature in a probe diode laser are described.

Atmospheric electromagnetic pulse propagation effects from thick targets in a terawatt laser target chamber

NASA Astrophysics Data System (ADS)

Remo, John L.; Adams, Richard G.; Jones, Michael C.

2007-08-01

Generation and effects of atmospherically propagated electromagnetic pulses (EMPs) initiated by photoelectrons ejected by the high density and temperature target surface plasmas from multiterawatt laser pulses are analyzed. These laser radiation pulse interactions can significantly increase noise levels, thereby obscuring data (sometimes totally) and may even damage sensitive probe and detection instrumentation. Noise effects from high energy density (approximately multiterawatt) laser pulses (˜300-400 ps pulse widths) interacting with thick (˜1 mm) metallic and dielectric solid targets and dielectric-metallic powder mixtures are interpreted as transient resonance radiation associated with surface charge fluctuations on the target chamber that functions as a radiating antenna. Effective solutions that minimize atmospheric EMP effects on internal and proximate electronic and electro-optical equipment external to the system based on systematic measurements using Moebius loop antennas, interpretations of signal periodicities, and dissipation indicators determining transient noise origin characteristics from target emissions are described. Analytic models for the effect of target chamber resonances and associated noise current and temperature in a probe diode laser are described.

Electromagnetic Test-Facility characterization: an identification approach

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

Zicker, J.E.; Candy, J.V.

The response of an object subjected to high energy, transient electromagnetic (EM) fields sometimes called electromagnetic pulses (EMP), is an important issue in the survivability of electronic systems (e.g., aircraft), especially when the field has been generated by a high altitude nuclear burst. The characterization of transient response information is a matter of national concern. In this report we discuss techniques to: (1) improve signal processing at a test facility; and (2) parameterize a particular object response. First, we discuss the application of identification-based signal processing techniques to improve signal levels at the Lawrence Livermore National Laboratory (LLNL) EM Transientmore » Test Facility. We identify models of test equipment and then use these models to deconvolve the input/output sequences for the object under test. A parametric model of the object is identified from this data. The model can be used to extrapolate the response to these threat level EMP. Also discussed is the development of a facility simulator (EMSIM) useful for experimental design and calibration and a deconvolution algorithm (DECONV) useful for removing probe effects from the measured data.« less

Atmospheric electromagnetic pulse propagation effects from thick targets in a terawatt laser target chamber

DOE PAGES

Remo, John L.; Adams, Richard G.; Jones, Michael C.

2007-08-16

Generation and effects of atmospherically propagated electromagnetic pulses (EMPs) initiated by photoelectrons ejected by the high density and temperature target surface plasmas from multiterawatt laser pulses are analyzed. These laser radiation pulse interactions can significantly increase noise levels, thereby obscuring data (sometimes totally) and may even damage sensitive probe and detection instrumentation. Noise effects from high energy density (approximately multiterawatt) laser pulses (~300–400 ps pulse widths) interacting with thick (~1 mm) metallic and dielectric solid targets and dielectric–metallic powder mixtures are interpreted as transient resonance radiation associated with surface charge fluctuations on the target chamber that functions as a radiatingmore » antenna. Effective solutions that minimize atmospheric EMP effects on internal and proximate electronic and electro-optical equipment external to the system based on systematic measurements using Moebius loop antennas, interpretations of signal periodicities, and dissipation indicators determining transient noise origin characteristics from target emissions are described. Analytic models for the effect of target chamber resonances and associated noise current and temperature in a probe diode laser are described.« less

Laser Microprobe Mass Spectrometry 1: Basic Principles and Performance Characteristics.

ERIC Educational Resources Information Center

Denoyer, Eric; And Others

1982-01-01

Describes the historical development, performance characteristics (sample requirements, analysis time, ionization characteristics, speciation capabilities, and figures of merit), and applications of laser microprobe mass spectrometry. (JN)

Assessing the Risk of Catastrophic Cyber Attack: Lessons from the Electromagnetic Pulse Commission

DTIC Science & Technology

2015-04-15

need to address whether it would do so? Fourth, the question of consequences must include not only the direct effects of any attack but also potential...inform cyber consequence assessments. Sixth, EMP effects are difficult to characterize but ultimately are knowable at the device level. The effects ...that the approach the EMP Commission used to assess the likelihood and consequences of EMP attacks could provide useful lessons for analysts grappling

Laser ablation ICP-MS analysis on nano-powder pellets and applications to granite bulk rock analysis

NASA Astrophysics Data System (ADS)

Wu, Shitou; Karius, Volker; Wörner, Gerhard

2017-04-01

Granites are a ubiquitous component of the continental crust and knowing their precise trace element signatures is essential in understanding the origins and evolution of the continental crust. ICP-MS bulk analysis of granite is generally conducted on solution after acid-digestion. However this technique has several deficiencies related to the difficulty of completely dissolving accessary minerals such as zircon and the instability/adsorption of high valence trace elements (Nb, Ta et al.) in acid solutions. The development of a nano-powder pellet technique by using wet milling procedure, and its combination with laser ablation ICP-MS has been proposed to overcome these problems. In this study, we produced nano-powders from a series of granite rock standards by wet milling in agate using a high power planetary ball mill instrument. The procedure was tested and optimized by modifying parameters (ball to powder ratio, water to powder ratio, milling power etc.). Characterization of nano-powders was conducted by various techniques including electron microprobe (EMP), secondary electron imaging, polarizing microscope, and laser particle size analyzer (LPSA) and laser scanning confocal microscope (LSCM). Particle sizes range from a few nm to 5 μm with a small secondary mode at around 10 to 20 μm that probably represent particle aggregates rather than remaining crystal grains after milling. Pellets of 5 mm in diameter were pressed into molds of cellulose at 1.75 *103 N/cm2. Surface roughness of the pellets was measured by LSCM and gave a Ra of 0.494 μm, which is an order higher than the surface of polished ATGH-G reference glass surface (Ra: 0.048 μm), but sufficient for laser ablation. Sources of contamination either from abrading agate balls or from ultrapure water were evaluated and quantified. The homogeneity of powder pellets down to less than 5 μm size was documented based on EMPA element mapping and statistical analyses of LA-ICP-MS in discrete spot and line scanning analytical mode. We report data from major to trace element (to < 0.1 ppm) of currently available international granite reference materials (JG-2, JG-3, GWB07103, GEB07111, GSP-2 and G-3) to evaluate analytical precision and accuracy of LA-ICP-MS measurements. Our results illustrate the potential of this method for high precision analysis of trace elements and e.g. Zr/Hf and Nb/Ta ratios in granites.

The study of voids in the AuAl thin-film system using the nuclear microprobe

NASA Astrophysics Data System (ADS)

de Waal, H. S.; Pretorius, R.; Prozesky, V. M.; Churms, C. L.

1997-07-01

A Nuclear Microprobe (NMP) was used to study void formation in thin film gold-aluminium systems. Microprobe Rutherford Backscattering Spectrometry (μRBS) was utilised to effectively obtain a three-dimensional picture of the void structure on the scale of a few nanometers in the depth dimension and a few microns in the in-plane dimension. This study illustrates the usefulness of the NMP in the study of materials and specifically thin-film structures.

EMP on a NTS experiment

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

Gilbert, J.; van Lint, V.; Sherwood, S.

This report is a compilation of two previous sets of pretest calculations, references 1 and 2 and the grounding and shielding report, reference 3. The calculations performed in reference 1 were made for the baseline system, with the instrumentation trailers not isolated from ground, and wider ranges of ground conductivity were considered. This was used to develop the grounding and shielding plan included in the appendix. The final pretest calculations of reference 2 were performed for the modified system with isolated trailers, and with a better knowledge of the ground conductivity. The basic driving mechanism for currents in the modelmore » is the motion of Compton electrons, driven by gamma rays, in the air gaps and soil. Most of the Compton current is balanced by conduction current which returns directly along the path of the Compton electron, but a small fraction will return by circuitous paths involving current flow on conductors, including the uphole cables. The calculation of the currents is done in a two step process -- first the voltages in the ground near the conducting metallic structures is calculated without considering the presence of the structures. These are then used as open circuit drivers for an electrical model of the conductors which is obtained from loop integrals of Maxwell`s equations. The model which is used is a transmission line model, similar to those which have been used to calculate EMP currents on buried and overhead cables in other situations, including previous underground tests, although on much shorter distance and time scales, and with more controlled geometries. The behavior of air gaps between the conducting structure and the walls of the drift is calculated using an air chemistry model which determines the electron and ion densities and uses them to calculate the air conductivity across the gap.« less

Gel shift analysis of the empA promoter region in Vibrio anguillarum

PubMed Central

Denkin, Steven M; Sekaric, Pedja; Nelson, David R

2004-01-01

Background The induction of metalloprotease encoded by empA in Vibrio anguillarum occurs at high cell density in salmon intestinal mucus. Previously we have shown that there are significant differences in empA expression in two strains of V. anguillarum, M93Sm and NB10. It is hypothesized that differences in empA regulation are due to differences in binding of regulatory elements. Results Two strains of V. anguillarum, M93Sm and NB10, were examined and compared for the presence of DNA regulatory proteins that bind to and control the empA promoter region. Gel mobility shift assays, using a digoxigenin (DIG)-labeled oligomer containing a lux box-like element and the promoter for empA, were done to demonstrate the presence of a DNA-binding protein. Protein extracts from NB10 cells incubated in Luria Bertani broth + 2% NaCl (LB20), nine salts solution + 200 μg/ml mucus (NSSM), 3M (marine minimal medium), or NSS resulted in a gel mobility shift. No gel mobility shift was seen when protein extracts from either LB20- or NSSM-grown M93Sm cells were mixed with the DIG-labeled empA oligomer. The azocasein assay detected protease activity in all incubation conditions for NB10 culture supernatants. In contrast, protease activity was detected in M93Sm culture supernatants only when incubated in NSSM. Since the luxR homologue in V. anguillarum, vanT, has been cloned, sequenced, and shown to be required for protease activity, we wanted to determine if vanT mutants of NB10 exhibit the same gel shift observed in the wild-type. Site-directed mutagenesis was used to create vanT mutants in V. anguillarum M93Sm and NB10 to test whether VanT is involved with the gel mobility shift. Both vanT mutants, M02 and NB02, did not produce protease activity in any conditions. However, protein extracts from NB02 incubated in each condition still exhibited a gel shift when mixed with the DIG-labeled empA oligomer. Conclusions The data demonstrate that protein extracts of V. anguillarum NB10 cells contain a protein that binds to a 50 bp oligomer containing the empA promoter-lux box-like region. NB10 cells express empA during stationary phase in all growth conditions. The DNA binding protein is not present in M93Sm extracts. M93Sm cells express protease activity only when incubated at high cell density in fish gastrointestinal mucus. The gel shift observed with NB10 cells is not due to VanT binding. The data also suggest that the DNA binding protein is responsible for the less restrictive expression of empA in NB10 compared to M93Sm. PMID:15516264

Magmatic-hydrothermal fluid interaction and mineralization in alkali-syenite nodules from the Breccia Museo pyroclastic deposit, Naples, Italy: Chapter 7 in Volcanism in the Campania Plain — Vesuvius, Campi Flegrei and Ignimbrites

USGS Publications Warehouse

Fedele, Luca; Tarzia, Maurizio; Belkin, Harvey E.; De Vivo, Benedetto; Lima, Annamaria; Lowenstern, Jacob

2007-01-01

The Breccia Museo, a pyroclastic flow that crops out in the Campi Flegrei volcanic complex (Naples, Italy), contains alkali-syenite (trachyte) nodules with enrichment in Cl and incompatible elements (e.g., U, Zr, Th, and rare-earth elements). Zircon was dated at ≈52 ka, by U-Th isotope systematics using a SHRIMP. Scanning electron microscope and electron microprobe analysis of the constituent phases have documented the mineralogical and textural evolution of the nodules of feldspar and mafic accumulations on the magma chamber margins. Detailed electron microprobe data are given for alkali and plagioclase feldspar, salite to ferrosalite clinopyroxene, pargasite, ferrogargasite, magnesio-hastingsite hornblende amphibole, biotite mica, Cl-rich scapolite, and a member (probable davyne-type) of the cancrinite group. Detailed whole rock, major and minor element data are also presented for selected nodules. A wide variety of common and uncommon accessory minerals were identified such as zircon, baddeleyite, zirconolite, pollucite, sodalite, titanite, monazite, cheralite, apatite, titanomagnetite and its alteration products, scheelite, ferberite, uraninite/thorianite, uranpyrochlore, thorite, pyrite, chalcopyrite, and galena. Scanning electron microscope analysis of opened fluid inclusions identified halite, sylvite, anhydrite, tungstates, carbonates, silicates, sulfides, and phosphates; most are probably daughter minerals. Microthermometric determinations on secondary fluid inclusions hosted by alkali feldspar define a temperature regime dominated by hypersaline aqueous fluids. Fluid-inclusion temperature data and mineral-pair geothermometers for coexisting feldspars and hornblende and plagioclase were used to construct a pressure-temperature scenario for the development and evolution of the nodules. We have compared the environment of porphyry copper formation and the petrogenetic environment constructed for the studied nodules. The suite of ore minerals observed in the nodules supports a potential for mineralization, which is similar to that observed in the alkaline volcanic systems of southern Italy (Pantelleria, Pontine Archipelago, Mt. Somma-Vesuvius).

A method of mounting multiple otoliths for beam-based microchemical analyses

USGS Publications Warehouse

Donohoe, C.J.; Zimmerman, C.E.

2010-01-01

Beam-based analytical methods are widely used to measure the concentrations of elements and isotopes in otoliths. These methods usually require that otoliths be individually mounted and prepared to properly expose the desired growth region to the analytical beam. Most analytical instruments, such as LA-ICPMS and ion and electron microprobes, have sample holders that will accept only one to six slides or mounts at a time. We describe a method of mounting otoliths that allows for easy transfer of many otoliths to a single mount after they have been prepared. Such an approach increases the number of otoliths that can be analyzed in a single session by reducing the need open the sample chamber to exchange slides-a particularly time consuming step on instruments that operate under vacuum. For ion and electron microprobes, the method also greatly reduces the number of slides that must be coated with an electrical conductor prior to analysis. In this method, a narrow strip of cover glass is first glued at one end to a standard microscope slide. The otolith is then mounted in thermoplastic resin on the opposite, free end of the strip. The otolith can then be ground and flipped, if needed, by reheating the mounting medium. After otolith preparation is complete, the cover glass is cut with a scribe to free the otolith and up to 20 small otoliths can be arranged on a single petrographic slide. ?? 2010 The Author(s).

APPLICATIONS OF CATHODOLUMINESCENCE OF QUARTZ AND FELDSPAR TO SEDIMENTARY PETROLOGY.

USGS Publications Warehouse

Ruppert, Leslie F.

1987-01-01

Cathodoluminescence (CL), the emission of visible light during electron bombardment, was first used in sandstone petrology in the mid-1960's. CL techniques are especially useful for determining the origin and source of quartz and feldspar, two of the most common constituents in clastic rocks. CL properties of both minerals are dependent on their temperature of crystallization, duration of cooling, and/or history of deformation. Detrital quartz and feldspar are typically derived from igneous and metamorphic sources and luminesce in the visible range whereas authigenic quartz and feldspar form at low temperatures and do not luminesce. Quantification of luminescent and non-luminescent quartz and feldspar with the scanning electron microscope, electron microprobe, or a commercial CL device can allow for the determination of origin, diagenesis, and source of clastic rocks when used in conjunction with field and other petrographic analyses.

Electrode erosion in steady-state electric propulsion engines

NASA Technical Reports Server (NTRS)

Pivirotto, Thomas J.; Deininger, William D.

1988-01-01

The anode and cathode of a 30 kW class arcjet engine were sectioned and analyzed. This arcjet was operated for a total time of 573 hr at power levels between 25 and 30 kW with ammonia at flow rates of 0.25 and 0.27 gm/s. The accumulated run time was sufficient to clearly establish erosion patterns and their causes. The type of electron emission from various parts of the cathode surface was made clear by scanning electron microscope analysis. A scanning electron microscope was used to study recrystallization on the hot anode surface. These electrodes were made of 2 percent thoriated tungsten and the surface thorium content and gradient perpendicular to the surfaces was determined by quantitative microprobe analysis. The results of this material analysis on the electrodes and recommendations for improving electrode operational life time are presented.

Unusual coexistence of extramedullary plasmacytoma and nasopharyngeal carcinoma in nasopharynx.

PubMed

Du, Ri-Chang; Li, Hai-Nan; Huang, Wei; Tian, Xiao-Ying; Li, Zhi

2015-09-17

Nasopharyngeal carcinoma (NPC) is an EBV-associated malignant tumor of nasopharynx. As extremely rare condition, the second primary cancer of nasopharynx can occur in NPC patients synchronously or subsequently. Extramedullary plasmacytoma (EMP) is a rare tumor and commonly originates in the head and neck region. However, there is no report to describe a collision tumor of NPC and EMP occurring in the same nasopharyngeal mass. We report here an unusual case of synchronous coexistence of NPC and EMP occurring in the nasopharynx of an old male patient. A 63-year-old male patient presented with a 3-month history of right-sided nasal obstruction and recently intermittent epistaxis without enlargement of cervical lymph nodes. The solitary mass of nasopharynx was found by radiological and nasopharyngeal examination. Histologically, the mass contained two separated portions and displayed typically histological features of NPC and EMP, respectively. In EMP portion, the tumor was composed of monomorphic plasmacytoid-appearing cells with immuno-positive to CD79a, CD138, CD38, MUM-1 and CD56, but lack immunoreactivity to pan-CK (AE1/AE3), CD20, CD21 and EBERs. In NPC portion, the tumor cells formed irregular-shaped islands with diffusely immuno-positive to pan-CK (AE1/AE3), EMA and EBERs, but lack expressions of lymphoplasmacytic markers. A diagnosis of simultaneous occurrence of EMP and NPC in nasopharynx was made. There was no evidence of tumor recurrence or metastasis 18-month follow-up after radiotherapy. To our knowledge, it may be the first case of coexistence of EMP and NPC synchronously. In addition, the histological differential diagnosis and relevant potential mechanism of this unusual collision tumor were also discussed.

A case–control study of mesothelioma in Minnesota iron ore (taconite) miners

PubMed Central

Lambert, Christine S; Alexander, Bruce H; Ramachandran, Gurumurthy; MacLehose, Richard F; Nelson, Heather H; Ryan, Andrew D; Mandel, Jeffrey H

2018-01-01

Objectives An excess of mesothelioma has been observed in iron ore miners in Northeastern Minnesota. Mining and processing of taconite iron ore generate exposures that include elongate mineral particles (EMPs) of amphibole and non-amphibole origin. We conducted a nested case–control study of mesothelioma in a cohort of 68 737 iron ore miners (haematite and taconite ore miners) to evaluate the association between mesothelioma, employment and EMP exposures from taconite mining. Methods Mesothelioma cases (N=80) were identified through the Minnesota Cancer Surveillance System (MCSS) and death certificates. Four controls of similar age were selected for each case with 315 controls ultimately eligible for inclusion. Mesothelioma risk was evaluated by estimating rate ratios and 95% CIs with conditional logistic regression in relation to duration of taconite industry employment and cumulative EMP exposure [(EMP/cc)×years], defined by the National Institute for Occupational Safety and Health (NIOSH) 7400 method. Models were adjusted for employment in haematite mining and potential exposure to commercial asbestos products used in the industry. Results All mesothelioma cases were male and 57 of the cases had work experience in the taconite industry. Mesothelioma was associated with the number of years employed in the taconite industry (RR=1.03, 95% CI 1.00 to 1.06) and cumulative EMP exposure (RR=1.10, 95% CI 0.97 to –1.24). No association was observed with employment in haematite mining. Conclusions These results support an association between mesothelioma and employment duration and possibly EMP exposure in taconite mining and processing. The type of EMP was not determined. The potential role of commercial asbestos cannot be entirely ruled out. PMID:26655961

Current Status of Infection Prevention and Control Programs for Emergency Medical Personnel in the Republic of Korea.

PubMed

Oh, Hyang Soon; Uhm, Dong Choon

2015-11-01

Emergency medical personnel (EMPs) are pre-hospital emergency responders who are at risk of exposure to infections and may also serve as a source for the transmission of infections. However, few studies of infection control have specifically addressed EMPs in the Republic of Korea (hereafter Korea). The goal of this study was to assess the current status of infection prevention and control programs (IPCPs) for EMPs in Korea. A cross-sectional survey was conducted to quantitatively assess the resources and activities of IPCPs. A total of 907 EMPs in five metropolitan cities completed a structured questionnaire from September 2014 to January 2015. The data were analyzed using descriptive statistics, multi-response analysis, and the chi-square test. The mean age of the participants was 34.8±15.1 years. IPCPs were found to have weaknesses with regard to the following resources: the assignment of infection control personnel (ICP) (79.5%), hand hygiene resources such as waterless antiseptics (79.3%), the use of paper towels (38.9%), personal protective equipment such as face shields (46.9%), and safety containers for sharps and a separated space for the disposal of infectious waste (10.1%). Likewise, the following activities were found to be inadequately incorporated into the workflow of EMPs: education about infection control (77.5%), post-exposure management (35.9%), and the decontamination of items and spaces after use (88.4%). ICP were found to have a significant effect on the resources and activities of IPCPs (p<0.001). The resources and activities of IPCPs were found to be significantly different among the five cities (p<0.001). IPCPs for EMPs showed some limitations in their resources and activities. IPCPs should be actively supported, and specific IPCP activities for EMPs should be developed.

THE SYNTHETIC-OVERSAMPLING METHOD: USING PHOTOMETRIC COLORS TO DISCOVER EXTREMELY METAL-POOR STARS

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

Miller, A. A., E-mail: amiller@astro.caltech.edu

2015-09-20

Extremely metal-poor (EMP) stars ([Fe/H] ≤ −3.0 dex) provide a unique window into understanding the first generation of stars and early chemical enrichment of the universe. EMP stars are exceptionally rare, however, and the relatively small number of confirmed discoveries limits our ability to exploit these near-field probes of the first ∼500 Myr after the Big Bang. Here, a new method to photometrically estimate [Fe/H] from only broadband photometric colors is presented. I show that the method, which utilizes machine-learning algorithms and a training set of ∼170,000 stars with spectroscopically measured [Fe/H], produces a typical scatter of ∼0.29 dex. Thismore » performance is similar to what is achievable via low-resolution spectroscopy, and outperforms other photometric techniques, while also being more general. I further show that a slight alteration to the model, wherein synthetic EMP stars are added to the training set, yields the robust identification of EMP candidates. In particular, this synthetic-oversampling method recovers ∼20% of the EMP stars in the training set, at a precision of ∼0.05. Furthermore, ∼65% of the false positives from the model are very metal-poor stars ([Fe/H] ≤ −2.0 dex). The synthetic-oversampling method is biased toward the discovery of warm (∼F-type) stars, a consequence of the targeting bias from the Sloan Digital Sky Survey/Sloan Extension for Galactic Understanding survey. This EMP selection method represents a significant improvement over alternative broadband optical selection techniques. The models are applied to >12 million stars, with an expected yield of ∼600 new EMP stars, which promises to open new avenues for exploring the early universe.« less

Increased Circulating Endothelial Apoptotic Microparticle to Endothelial Progenitor Cell Ratio Is Associated with Subsequent Decline in Glomerular Filtration Rate in Hypertensive Patients

PubMed Central

Hsu, Chien-Yi; Huang, Po-Hsun; Chiang, Chia-Hung; Leu, Hsin-Bang; Huang, Chin-Chou; Chen, Jaw-Wen; Lin, Shing-Jong

2013-01-01

Background Recent research indicates hypertensive patients with microalbuminuria have decreased endothelial progenitor cells (EPCs) and increased levels of endothelial apoptotic microparticles (EMP). However, whether these changes are related to a subsequent decline in glomerular filtration rate (GFR) remains unclear. Methods and Results We enrolled totally 100 hypertensive out-patients with eGFR ≥30 mL/min/1.73 m2. The mean annual rate of GFR decline (△GFR/y) was −1.49±3.26 mL/min/1.73 m2 per year during the follow-up period (34±6 months). Flow cytometry was used to assess circulating EPC (CD34+/KDR+) and EMP levels (CD31+/annexin V+) in peripheral blood. The △GFR/y was correlated with the EMP to EPC ratio (r = −0.465, p<0.001), microalbuminuria (r = −0.329, p = 0.001), and the Framingham risk score (r = −0.245, p = 0.013). When we divided the patients into 4 groups according to the EMP to EPC ratio, there was an association between the EMP to EPC ratio and the ΔGFR/y (mean ΔGFR/y: 0.08±3.04 vs. −0.50±2.84 vs. −1.25±2.49 vs. −4.42±2.82, p<0.001). Multivariate analysis indicated that increased EMP to EPC ratio is an independent predictor of ΔeGFR/y. Conclusions An increased circulating EMP to EPC ratio is associated with subsequent decline in GFR in hypertensive patients, which suggests endothelial damage with reduced vascular repair capacity may contribute to further deterioration of renal function in patients with hypertension. PMID:23874701

A case-control study of mesothelioma in Minnesota iron ore (taconite) miners.

PubMed

Lambert, Christine S; Alexander, Bruce H; Ramachandran, Gurumurthy; MacLehose, Richard F; Nelson, Heather H; Ryan, Andrew D; Mandel, Jeffrey H

2016-02-01

An excess of mesothelioma has been observed in iron ore miners in Northeastern Minnesota. Mining and processing of taconite iron ore generate exposures that include elongate mineral particles (EMPs) of amphibole and non-amphibole origin. We conducted a nested case-control study of mesothelioma in a cohort of 68,737 iron ore miners (haematite and taconite ore miners) to evaluate the association between mesothelioma, employment and EMP exposures from taconite mining. Mesothelioma cases (N=80) were identified through the Minnesota Cancer Surveillance System (MCSS) and death certificates. Four controls of similar age were selected for each case with 315 controls ultimately eligible for inclusion. Mesothelioma risk was evaluated by estimating rate ratios and 95% CIs with conditional logistic regression in relation to duration of taconite industry employment and cumulative EMP exposure [(EMP/cc)×years], defined by the National Institute for Occupational Safety and Health (NIOSH) 7400 method. Models were adjusted for employment in haematite mining and potential exposure to commercial asbestos products used in the industry. All mesothelioma cases were male and 57 of the cases had work experience in the taconite industry. Mesothelioma was associated with the number of years employed in the taconite industry (RR=1.03, 95% CI 1.00 to 1.06) and cumulative EMP exposure (RR=1.10, 95% CI 0.97 to -1.24). No association was observed with employment in haematite mining. These results support an association between mesothelioma and employment duration and possibly EMP exposure in taconite mining and processing. The type of EMP was not determined. The potential role of commercial asbestos cannot be entirely ruled out. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Picosecond Dynamics of Excitonic Magnetic Polarons in Colloidal Diffusion-Doped Cd(1-x)Mn(x)Se Quantum Dots.

PubMed

Nelson, Heidi D; Bradshaw, Liam R; Barrows, Charles J; Vlaskin, Vladimir A; Gamelin, Daniel R

2015-11-24

Spontaneous magnetization is observed at zero magnetic field in photoexcited colloidal Cd(1-x)Mn(x)Se (x = 0.13) quantum dots (QDs) prepared by diffusion doping, reflecting strong Mn(2+)-exciton exchange coupling. The picosecond dynamics of this phenomenon, known as an excitonic magnetic polaron (EMP), are examined using a combination of time-resolved photoluminescence, magneto-photoluminescence, and Faraday rotation (TRFR) spectroscopies, in conjunction with continuous-wave absorption, magnetic circular dichroism (MCD), and magnetic circularly polarized photoluminescence (MCPL) spectroscopies. The data indicate that EMPs form with random magnetization orientations at zero external field, but their formation can be directed by an external magnetic field. After formation, however, external magnetic fields are unable to reorient the EMPs within the luminescence lifetime, implicating anisotropy in the EMP potential-energy surfaces. TRFR measurements in a transverse magnetic field reveal rapid (<5 ps) spin transfer from excitons to Mn(2+) followed by coherent EMP precession at the Mn(2+) Larmor frequency for over a nanosecond. A dynamical TRFR phase inversion is observed during EMP formation attributed to the large shifts in excitonic absorption energies during spontaneous magnetization. Partial optical orientation of the EMPs by resonant circularly polarized photoexcitation is also demonstrated. Collectively, these results highlight the extraordinary physical properties of colloidal diffusion-doped Cd(1-x)Mn(x)Se QDs that result from their unique combination of strong quantum confinement, large Mn(2+) concentrations, and relatively narrow size distributions. The insights gained from these measurements advance our understanding of spin dynamics and magnetic exchange in colloidal doped semiconductor nanostructures, with potential ramifications for future spin-based information technologies.

Retrospective survey of the efficacy of mandatory implementation of the Essential Medicine Policy in the primary healthcare setting in China: failure to promote the rational use of antibiotics in clinics.

PubMed

Xiao, Yonghong; Wang, Jin; Shen, Ping; Zheng, Beiwen; Zheng, Yingdong; Li, Lanjuan

2016-10-01

The objective of this study was to understand the impact of implementation of the Essential Medicine Policy (EMP) on the rational use of antibiotics in primary medical institutions in China. A retrospective survey was conducted in 39 primary medical institutions to compare the efficacy of EMP in rational antibiotic use. All institutions completed the survey 1 year before and 1 year after implementation of the EMP. In particular, antibiotic use and its rationality were closely examined. The institutions mainly dealt with common diseases, especially non-infectious chronic diseases. Antibiotic usage was very inappropriate both before and after EMP implementation. Before and after EMP implementation, respectively, the median outpatient cost was US$6.34 and US$5.05, 52.50% (2005/3819) and 53.41% (1865/3492) of the outpatient prescriptions contained antibiotics, and 76.23% (1132/1485) and 78.83% (1106/1403) of inpatients were administered antibiotics. In addition, 98.38% (425/432) and 97.52% (512/525) of surgical inpatients were administered antibiotics, respectively, and 80.76% (638/790) and 75.19% (503/669) of patients with a cold were prescribed antibiotics, respectively. The most commonly used antibiotics were broad-spectrum and injectable agents, including cephalosporins, fluoroquinolones and penicillins. This profile showed little change following implementation of the EMP. In conclusion, inappropriate antibiotic use is a serious problem in primary medical institutions in China. Whilst enforcing the EMP reduced the cost of medical services, it had little effect on promoting the rational use of antibiotics. Copyright © 2016 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

Endothelial microparticles: Sophisticated vesicles modulating vascular function

PubMed Central

Curtis, Anne M; Edelberg, Jay; Jonas, Rebecca; Rogers, Wade T; Moore, Jonni S; Syed, Wajihuddin; Mohler, Emile R

2015-01-01

Endothelial microparticles (EMPs) belong to a family of extracellular vesicles that are dynamic, mobile, biological effectors capable of mediating vascular physiology and function. The release of EMPs can impart autocrine and paracrine effects on target cells through surface interaction, cellular fusion, and, possibly, the delivery of intra-vesicular cargo. A greater understanding of the formation, composition, and function of EMPs will broaden our understanding of endothelial communication and may expose new pathways amenable for therapeutic manipulation. PMID:23892447

Pathologic Mechanical Stress and Endotoxin Exposure Increases Lung Endothelial Microparticle Shedding

PubMed Central

Letsiou, Eleftheria; Sammani, Saad; Zhang, Wei; Zhou, Tong; Quijada, Hector; Moreno-Vinasco, Liliana; Dudek, Steven M.

2015-01-01

Acute lung injury (ALI) results from infectious challenges and from pathologic lung distention produced by excessive tidal volume delivered during mechanical ventilation (ventilator-induced lung injury [VILI]) and is characterized by extensive alveolar and vascular dysfunction. Identification of novel ALI therapies is hampered by the lack of effective ALI/VILI biomarkers. We explored endothelial cell (EC)-derived microparticles (EMPs) (0.1–1 μm) as potentially important markers and potential mediators of lung vascular injury in preclinical models of ALI and VILI. We characterized EMPs (annexin V and CD31 immunoreactivity) produced from human lung ECs exposed to physiologic or pathologic mechanical stress (5 or 18% cyclic stretch [CS]) or to endotoxin (LPS). EC exposure to 18% CS or to LPS resulted in increased EMP shedding compared with static cells (∼ 4-fold and ∼ 2.5-fold increases, respectively). Proteomic analysis revealed unique 18% CS–derived (n = 10) and LPS-derived EMP proteins (n = 43). VILI-challenged mice (40 ml/kg, 4 h) exhibited increased plasma and bronchoalveolar lavage CD62E (E-selectin)-positive MPs compared with control mice. Finally, mice receiving intratracheal instillation of 18% CS–derived EMPs displayed significant lung inflammation and injury. These findings indicate that ALI/VILI-producing stimuli induce significant shedding of distinct EMP populations that may serve as potential ALI biomarkers and contribute to the severity of lung injury. PMID:25029266

SPE-LEEM Studies on the Surface and Electronic Structure of 2-D Transition Metal Dichalcogenides

NASA Astrophysics Data System (ADS)

Yeh, Po-Chun; Jin, Wencan; Zaki, Nader; Zhang, Datong; Sadowski, Jerzy; Al-Mahboob, Abdullah; van de Zande, Arend; Chenet, Daniel; Dadap, Jerry; Herman, Irving; Sutter, Petter; Hone, James; Osgood, Richard

2014-03-01

In this work, we studied the surface and electronic structure of monolayer and few-layer exfoliated MoS2 and WSe2, as well as chemical-vapor-deposition (CVD) grown MoS2, using Spectroscopic Photoemission and Low Energy Electron Microscope (SPE-LEEM). LEEM measurements reveal that, unlike exfoliated MoS2, CVD-grown MoS2 exhibits grain-boundary alterations due to surface strain. However, LEEM and micro-probe low energy electron diffraction show that the quality of CVD-grown MoS2 is comparable to that of exfoliated MoS2. Micrometer-scale angle-resolved photoemission spectroscopy (ARPES) measurement on exfoliated MoS2 and WSe2 single-crystals provides direct evidence for the shifting of the valence band maximum from Γ to K, when the layer number is thinned down to one, as predicted by density functional theory. Our measurements of the k-space resolved electronic structure allow for further comparison with other theoretical predictions and with transport measurements. Session I and II

The role of radiation therapy in the treatment of solitary plasmacytomas.

PubMed

Mayr, N A; Wen, B C; Hussey, D H; Burns, C P; Staples, J J; Doornbos, J F; Vigliotti, A P

1990-04-01

Between 1960 and 1985, 30 patients with solitary plasmacytomas were treated with radiotherapy at the University of Iowa: 13 patients with extramedullary plasmacytomas (EMP) and 17 with solitary plasmacytomas of bone (SPB). The local control rates were 92% for patients with EMP and 88% for those with SPB. Two of nine patients (22%) with EMP treated to the primary tumor only developed regional lymph node metastasis, indicating the need for elective irradiation of this area. The most common pattern of failure in both groups was progression to multiple myeloma. This occurred in 23% of the patients with EMP and 53% of those with SPB. The time course of progression to multiple myeloma differed for the two groups. All of those who progressed to multiple myeloma in the EMP group did so within 2 years, whereas a significant number of those in the SPB group progressed more than 5 years after initial therapy. None of five patients who received adjuvant chemotherapy in the SPB group progressed to multiple myeloma, compared to 75% (9/12) of the patients who did not receive chemotherapy.

Study on the Shielding Effectiveness of an Arc Thermal Metal Spraying Method against an Electromagnetic Pulse

PubMed Central

Lee, Han-Seung; Choe, Hong-Bok; Baek, In-Young

2017-01-01

An electromagnetic pulse (EMP) explodes in real-time and causes critical damage within a short period to not only electric devices, but also to national infrastructures. In terms of EMP shielding rooms, metal plate has been used due to its excellent shielding effectiveness (SE). However, it has difficulties in manufacturing, as the fabrication of welded parts of metal plates and the cost of construction are non-economical. The objective of this study is to examine the applicability of the arc thermal metal spraying (ATMS) method as a new EMP shielding method to replace metal plate. The experimental parameters, metal types (Cu, Zn-Al), and coating thickness (100–700 μm) used for the ATMS method were considered. As an experiment, a SE test against an EMP in the range of 103 to 1010 Hz was conducted. Results showed that the ATMS coating with Zn-Al had similar shielding performance in comparison with metal plate. In conclusion, the ATMS method is judged to have a high possibility of actual application as a new EMP shielding material. PMID:28976931

Study on the Shielding Effectiveness of an Arc Thermal Metal Spraying Method against an Electromagnetic Pulse.

PubMed

Lee, Han-Seung; Choe, Hong-Bok; Baek, In-Young; Singh, Jitendra Kumar; Ismail, Mohamed A

2017-10-04

An electromagnetic pulse (EMP) explodes in real-time and causes critical damage within a short period to not only electric devices, but also to national infrastructures. In terms of EMP shielding rooms, metal plate has been used due to its excellent shielding effectiveness (SE). However, it has difficulties in manufacturing, as the fabrication of welded parts of metal plates and the cost of construction are non-economical. The objective of this study is to examine the applicability of the arc thermal metal spraying (ATMS) method as a new EMP shielding method to replace metal plate. The experimental parameters, metal types (Cu, Zn-Al), and coating thickness (100-700 μm) used for the ATMS method were considered. As an experiment, a SE test against an EMP in the range of 103 to 1010 Hz was conducted. Results showed that the ATMS coating with Zn-Al had similar shielding performance in comparison with metal plate. In conclusion, the ATMS method is judged to have a high possibility of actual application as a new EMP shielding material.

In vivo monitoring of nanosphere onsite delivery using fiber optic microprobe

NASA Astrophysics Data System (ADS)

Lo, Leu-Wei; Yang, Chung-Shi

2005-02-01

To recognize the information of ischemia-induced blood vessel permeability would be valuable to formulate the drugs for optimal local delivery, we constructed an implantable needle type fiber-optic microprobe for the monitoring of in vivo fluorescent substances in anesthetized rats. This fiber-optic microprobe was composed of coaxial optical fibers and catheterized using a thin wall tubing of stainless steel (~400 um O.D. and ~300 um I.D.). The central fiber, with 100 um core diameter and 20 um cladding, coated with a 30 um layer of gold, was surrounded by 10 fibers with 50 um cores. The central fiber carried the light from the 488 nm Argon laser to the tissue while the surrounding fibers collected the emitted fluorescence to the detector. When the fiber-optic microprobe was placed in the solutions containing various concentrations of fluorescent nanospheres (20 nm), either with or without 10% lipofundin as optical phantom, nanosphere concentration-dependent responses of the fluorescence intensity were observed. The microprobe was then implanted into the liver and the brain of anesthetized rats to monitor the in situ extravasation of pre-administered fluorescent nanospheres from vasculature following the ischemic insults. Both the hepatic and cerebral ischemic insults showed immediate increases of the extracellular 20 nm fluorescent nanospheres. The implantable fiber-optic microprobe constructed in present study provides itself as a minimally-invasive technique capable of investigating the vascular permeability for in vivo nanosphere delivery in both ischemic liver and brain.

CAMECA IMS 1300-HR3: The New Generation Ion Microprobe

NASA Astrophysics Data System (ADS)

Peres, P.; Choi, S. Y.; Renaud, L.; Saliot, P.; Larson, D. J.

2016-12-01

The success of secondary ion mass spectrometry (SIMS) in Geo- and Cosmo-chemistry relies on its performance in terms of: 1) very high sensitivity (mandatory for high precision measurements or to achieve low detection limits); 2) a broad mass range of elemental and isotopic species, from low mass (H) to high mass (U and above); 3) in-situ analysis of any solid flat polished surface; and 4) high spatial resolution from tens of microns down to sub-micron scale. The IMS 1300-HR3 (High Reproducibility, High spatial Resolution, High mass Resolution) is the latest generation of CAMECA's large geometry magnetic sector SIMS (or ion microprobe), successor to the internationally recognized IMS 1280-HR. The 1300-HR3delivers unmatched analytical performance for a wide range of applications (stable isotopes, geochronology, trace elements, nuclear safeguards and environmental studies…) due to: • High brightness RF-plasma oxygen ion source with enhanced beam density and current stability, dramatically improving spatial resolution, data reproducibility, and throughput • Automated sample loading system with motorized sample height (Z) adjustment, significantly increasing analysis precision, ease-of-use, and productivity • UV-light microscope for enhanced optical image resolution, together with dedicated software for easy sample navigation (developed by University of Wisconsin, USA) • Low noise 1012Ω resistor Faraday cup preamplifier boards for measuring low signal intensities In addition, improvements in electronics and software have been integrated into the new instrument. In order to meet a growing demand from geochronologists, CAMECA also introduces the KLEORA, which is a fully optimized ion microprobe for advanced mineral dating derived from the IMS 1300-HR3. Instrumental developments as well as data obtained for stable isotope and U-Pb dating applications will be presented in detail.

Technology of fast spark gaps

NASA Astrophysics Data System (ADS)

Standler, Ronald B.

1989-09-01

To protect electronic systems from the effects of electromagnetic pulse (EMP) form nuclear weapons and high-power microwave (HPM) weapons, it is desirable to have fast responding protection components. The gas-filled spark gap appears to be an attractive protection component, except that it can be slow to conduct under certain conditions. This report reviews the literature and presents ideas for construction of a spark gap that will conduct in less than one nanosecond. The key concept to making a fast-responding spark gap is to produce a large number of free electrons quickly. Seven different mechanisms for production of free electrons are reviewed, and several that are relevant to miniature spark gaps for protective applications are discussed in detail. These mechanisms include: inclusion of radioactive materials, photoelectric effect, secondary electrode emission from the anode, and field emission from the cathode.

Proceedings of the Conference on the Design of Experiments in Army Research, Development, and Testing (33rd)

DTIC Science & Technology

1988-05-01

Evaluation Directorate (ARMTE) was tasked to conduct a "side- by-side" comparison of EMPS vs . DATMs and to conduct a human factors evaluation of the EMPS...performance ("side-by-side") comparison of EMPS vs . DATMs and to conduct a human factors evaluation. The performance evaluation was based on the speed... independent targets over time. To acquire data for this research, the BRL conducted a statistically designed exper- iment, the Firepower Control Experiment

47 CFR 215.0 - Purpose and authority.

Code of Federal Regulations, 2010 CFR

2010-10-01

... POINT FOR ELECTROMAGNETIC PULSE (EMP) INFORMATION § 215.0 Purpose and authority. The purpose of this part is to designate a focal point within the Federal Government for electromagnetic pulse (EMP...

47 CFR 215.0 - Purpose and authority.

Code of Federal Regulations, 2013 CFR

2013-10-01

... POINT FOR ELECTROMAGNETIC PULSE (EMP) INFORMATION § 215.0 Purpose and authority. The purpose of this part is to designate a focal point within the Federal Government for electromagnetic pulse (EMP...

47 CFR 215.0 - Purpose and authority.

Code of Federal Regulations, 2011 CFR

2011-10-01

... POINT FOR ELECTROMAGNETIC PULSE (EMP) INFORMATION § 215.0 Purpose and authority. The purpose of this part is to designate a focal point within the Federal Government for electromagnetic pulse (EMP...

47 CFR 215.0 - Purpose and authority.

Code of Federal Regulations, 2014 CFR

2014-10-01

... POINT FOR ELECTROMAGNETIC PULSE (EMP) INFORMATION § 215.0 Purpose and authority. The purpose of this part is to designate a focal point within the Federal Government for electromagnetic pulse (EMP...

47 CFR 215.0 - Purpose and authority.

Code of Federal Regulations, 2012 CFR

2012-10-01

... POINT FOR ELECTROMAGNETIC PULSE (EMP) INFORMATION § 215.0 Purpose and authority. The purpose of this part is to designate a focal point within the Federal Government for electromagnetic pulse (EMP...

Limitations on analysis of small particles with an electron probe: pollution studies

USGS Publications Warehouse

Heidel, R.H.; Desborough, G.A.

1975-01-01

Recent literature concerning the size and composition of airborne lead particles in automobile exhaust emissions determined by electron microprobe analysis reports 14 distinct lead compounds. Particle sizes reported were from 0.2 ??m to 2 ??m in the diameter. The determination of chemical formulae for compounds requires quantitative elemental data for individual particles. It was also assumed that the lead bearing particles analysed were solid (specifically non porous or non fluffy) compounds which occurred as discrete (non aggregate) particles. Intensity data obtained in the laboratory from the excited volume in a 1 ??m diameter sphere of solid lead chloride indicate insufficient precision and sensitivity to obtain chemical formulae as reported in the literature for exhaust emission products.

Apollo 15 yellow-brown volcanic glass - Chemistry and petrogenetic relations to green volcanic glass and olivine-normative mare basalts

NASA Technical Reports Server (NTRS)

Hughes, S. S.; Schmitt, R. A.; Delano, J. W.

1988-01-01

Electron microprobe and INAA were used to analyze forty spherules of Apollo 15 yellow-brown glass for major and trace elements. The glass is one of twenty-five high-Mg primary magmas emplaced on the lunar surface in pyroclastic eruptions. The abundances show that the magma was produced by partial melting of differentiated cumulates in the lunar mantle. Models to explain the possible source-regions of several Apollo 15 and Apollo 12 low-Ti mare magmas are presented.

Contamination analyses of technology mirror assembly optical surfaces

NASA Technical Reports Server (NTRS)

Germani, Mark S.

1991-01-01

Automated electron microprobe analyses were performed on tape lift samples from the Technology Mirror Assembly (TMA) optical surfaces. Details of the analyses are given, and the contamination of the mirror surfaces is discussed. Based on the automated analyses of the tape lifts from the TMA surfaces and the control blank, we can conclude that the particles identified on the actual samples were not a result of contamination due to the handling or sampling process itself and that the particles reflect the actual contamination on the surface of the mirror.

Chemistry and particle track studies of Apollo 14 glasses.

NASA Technical Reports Server (NTRS)

Glass, B. P.; Storzer, D.; Wagner, G. A.

1972-01-01

The abundance and the composition of Apollo 14 glasses have been studied. Glass particles were analyzed for Si, Ti, Al, Fe, Mn, Mg, Na, and K by electron microprobe analysis. The refractive indices of 26 particles were determined by the oil immersion method. Track analyses have been carried out in order to determine the uranium content and the radiation history of glass particles. The proper identification of galactic and solar flare nuclei tracks makes it possible to estimated residence times of the glass particles in the top layer of the lunar soil.

Studies related to the surfaces of the moon and planets. [a discussion of vapor deposition and glasses of lunar composition

NASA Technical Reports Server (NTRS)

Hapke, B.

1974-01-01

A variety of glasses of lunar composition were prepared with different amounts of Fe and Ti under both reducing and oxidizing conditions, and also by sputter-deposition and thermal evaporation and condensation. These materials were analyzed by wet chemical, electron microprobe, ESR, Mossbauer and magnetic methods. The effects of darkening processes on surface soils of airless bodies are discussed along with the effects of vapor phase deposition processes on the optical, chemical, and magnetic properties of the lunar regolith.

As-received microstructure of a SiC/Ti-15-3 composite

NASA Technical Reports Server (NTRS)

Lerch, Bradley A.; Hull, David R.; Leonhardt, Todd A.

1988-01-01

A silicon carbide fiber reinforced titanium (Ti-15V-3Cr-3Sn-3Al) composite is metallographically examined. Several methods for examining composite materials are investigated and documented. Polishing techniques for this material are described. An interference layering method is developed to reveal the structure of the fiber, the reaction zone, and various phases within the matrix. Microprobe and transmission electron microscope (TEM) analyses are performed on the fiber/matrix interface. A detailed description of the fiber distribution as well as the microstructure of the fiber and matrix are presented.

Evaluation of hot corrosion behavior of thermal barrier coatings

NASA Technical Reports Server (NTRS)

Hodge, P. E.; Miller, R. A.; Gedwill, M. A.

1980-01-01

Calcium silicate and yttria stabilized zirconia/MCrAlY thermal barrier coating systems on air-cooled specimens were exposed to sodium plus vanadium doped Mach 0.3 combustion gases. Thermal barrier coating endurance was determined to be a strong inverse function of ceramic coating thickness. Coating system durability was increased through the use of higher Cr + Al NiCrAl and CoCrAlY bond coatings. Chemical and electron microprobe analyses supported the predictions of condensate compositions and the determination of their roles in causing spalling of the ceramic coatings.

PROGRESS ON THE STUDY OF THE URANIUM-ALUMINUM-IRON CONSTITUTION DIAGRAM FOR THE PERIOD SEPTEMBER 1-DECEMBER 31, 1963

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

Russell, R.B.

The U--Al--Fe constitution diagram up to about 1000 ppm each of aluminum and iron is sthdied. The techniques used for this study include optical, electron, and x-ray metallography; microprobe analysis, electric conductivity, and hardness measurements. A combination of techniques are giving evidence of the amount of solid solubility of aluminum and iron in alpha, beta, and gamma uranium at selected higher temperatures. The U-Al and U-Fe phase diagrams are also being determined. (N.W.R.)

Coexisting cummingtonite and aluminous hornblende from garnet amphibolite, Boehls Butte area, Idaho, USA

USGS Publications Warehouse

Hietanen, A.

1973-01-01

Electron microprobe analyses of green hornblende and coexisting cummingtonite from garnet amphibolite show identical Fe/Mg ratios ( = 0.9). Cummingtonite is iron-magnesium silicate with very little calcium and aluminum and practically no alkalies. In contrast, the hornblende has 1.5 tetrahedral Al, 0.9 octahedral Al and a considerable amount of Ca and alkalies. Comparison with the hornblendes from the Sierra Nevada shows a higher relative amount of tschemakite molecule in the hornblendes from Idaho where pressures during the recrystallization were higher. ?? 1973.

Electromagnetic Pulse (EMP) survey of the Louisiana State Emergency Operating Center, Baton Rouge, Louisiana

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

Crutcher, R.I.; Buchanan, M.E.; Jones, R.W.

1989-08-01

The purpose of this report is to develop an engineering design package to protect the federal Emergency Management Agency (FEMA) National Radio System (FNARS) facilities from the effects of high-altitude electromagnetic pulses (HEMP). This report refers to the Louisiana State Emergency Operating Center (EOC) in Baton Rouge, Louisiana. This report addresses electromagnetic pulse (EMP) effects only, and disregards any condition in which radiation effects may be a factor. It has been established that, except for the source region of a surface burst, EMP effects of high-altitude bursts are more severe than comparable detonations in either air or surface regions. Anymore » system hardened to withstand the more extreme EMP environment will survive the less severe conditions. The threatening environment will therefore be limited to HEMP situations. 76 figs., 2 tabs.« less

The use of commercial off-the-shelf equipment and its impact on C3 (Command, Control and Communications EMP (electromagnetic pulse) survivability

NASA Astrophysics Data System (ADS)

Hoke, Melvin D., Jr.

1988-04-01

The President's Blue Ribbon Commission on Defense Management has recommended that the military should make greater use of off-the-shelf components, systems, and services (also know as Non-Developmental Items or NDI). This recommendation, if blindly implemented, could have an adverse impact on the survivability of critical command, control, and communications assets. The study evaluates how the electromagnetic pulse (EMP) survivability of a strategic, time-urgent, fixed, ground-based, Command, Control, and Communications (C3) facility would be impacted by the use of off-the-shelf C3 equipments. The study concludes that to have a quantifiable measure of confidence in the facility's EMP survivability, the piece of off-the-shelf equipment under consideration will first have to be subjected to some degree of EMP testing.

Nuclear pulse. III - Playing a wild card

NASA Astrophysics Data System (ADS)

Broad, W. J.

1981-06-01

Implications of the phenomenon of electromagnetic pulse (EMP), a high-voltage by-product of nuclear explosions in space which could render useless unprotected communications equipment and power grids over a wide area, for the feasibility of conducting a limited nuclear war by the United States are discussed. Arguments on the one hand that the effects of EMP demand direct investigation and should be protected against by the hardening of U.S. military communications are summarized and contrasted with those on the other hand which assert that the presence of EMP, as well as other exotic nuclear effects, would, despite any attempts at hardening, make it impossible to maintain the precision of command and control necessary for a limited nuclear action against Soviet military targets. Uncertainties about Soviet intentions in regard to the use of EMP as a weapon are also pointed out.

TOPoS: chemical study of extremely metal-poor stars.

NASA Astrophysics Data System (ADS)

Caffau, E.; Sbordone, L.; Bonifacio, P.; Cayrel, R.; Christlieb, N.; Clark, P.; François, P.; Glover, S.; Klessen, R.; Koch, A.; Ludwig, H.-G.; Monaco, L.; Plez, B.; Spite, F.; Spite, M.; Steffen, M.; Zaggia, S.

The extremely metal-poor (EMP) stars hold in their atmospheres the fossil record of the chemical composition of the early phases of the Galactic evolution. The chemical analysis of such objects provides important constraints on these early phases. EMP stars are very rare objects; to dig them out, large amounts of data have to be processed. With an automatic procedure, we analysed objects with colours of Turn-Off stars from the Sloan Digital Sky Survey to select a sample of good candidate EMP stars. In the latest years, we observed a sample of these candidates with X-Shooter and UVES, and we have an ongoing ESO large programme to use these spectrographs to observe EMP stars. I will report here the results on metallicity and Strontium abundance. Based on observations obtained at ESO Paranal Observatory, programme 189.D-0165(A)

Extramedullary plasmacytoma in the carotid space: Expanding the differential diagnosis.

PubMed

Deshpande, Sneha Satish; Kane, Shubhada; Arya, Supreeta

2014-10-01

Plasma cell neoplasms have been classified into various types, with a range of clinical and radiological presentations. Extramedullary plasmacytoma (EMP) is a subset of plasma cell neoplasms which presents as an isolated non-osseous soft tissue mass. Though carotid space neoplasms are commonly encountered, EMP in the carotid space is rare and seldom considered in the initial differential diagnosis of a carotid space mass. These tumors can be treated by surgery or radiotherapy. On the other hand, the commonly encountered tumors in the carotid space are treated surgically. Also, it is mandatory to exclude multiple myeloma in the patients presenting with EMP. Hence, accurate and early diagnosis has therapeutic and prognostic implications. We report a rare case of EMP of the carotid space, describing the imaging features and the differential diagnoses with clues pointing to this rare entity.

A Search for Meteoroid Lunar Impact Generated Electromagnetic Pulses

NASA Astrophysics Data System (ADS)

Kesaraju, Saiveena; Mathews, John D.; Vierinen, Juha; Perillat, Phil; Meisel, David D.

2016-11-01

Lunar white light flashes associated with meteoroid impacts are now regularly observed using modest optical instrumentation. In this paper, we hypothesize that the developing, optically-dense hot ejecta cloud associated with these hypervelocity impacts also produce an associated complex plasma component that rapidly evolves resulting in a highly-transient electro magnetic pulse (EMP) in the VHF/UHF spectral region. Discovery of the characteristics and event frequency of impact EMPs would prove interesting to meteoroid flux and complex plasma physics studies especially if EMPs from the same event are detected from at least two locations on the Earth with relative delays appropriate to the propagation paths. We describe a prototype observational search, conducted in May 2014, for meteoroid lunar-impact EMPs that was conducted using simultaneous, overlapping-band, UHF radio observations at the Arecibo (AO; Puerto Rico) and Haystack (HO, Massachusetts, USA) Observatories. Monostatic/bistatic lunar radar imaging observations were also performed with HO transmitting and HO/AO receiving to confirm tracking, the net delay, and the pointing/timing ephemeris at both observatories. Signal analysis was performed using time-frequency signal processing techniques. Although, we did not conclusively identify EMP returns, this search detected possible EMPs and we have confirmed the search paradigm and established the sensitivity of the AO-HO system in detecting the hypothesized events. We have also characterized the difficult radio-frequency interference environment surrounding these UHF observations. We discuss the wide range of terrestrial-origin, Moon-bounce signals that were observed which additionally validate the observational technique. Further observations are contemplated.

EPOR-Based Purification and Analysis of Erythropoietin Mimetic Peptides from Human Urine by Cys-Specific Cleavage and LC/MS/MS

NASA Astrophysics Data System (ADS)

Vogel, Matthias; Thomas, Andreas; Schänzer, Wilhelm; Thevis, Mario

2015-09-01

The development of a new class of erythropoietin mimetic agents (EMA) for treating anemic conditions has been initiated with the discovery of oligopeptides capable of dimerizing the erythropoietin (EPO) receptor and thus stimulating erythropoiesis. The most promising amino acid sequences have been mounted on various different polymeric structures or carrier molecules to obtain highly active EPO-like drugs exhibiting beneficial and desirable pharmacokinetic profiles. Concomitant with creating new therapeutic options, erythropoietin mimetic peptide (EMP)-based drug candidates represent means to artificially enhance endurance performance and necessitate coverage by sports drug testing methods. Therefore, the aim of the present study was to develop a strategy for the comprehensive detection of EMPs in doping controls, which can be used complementary to existing protocols. Three model EMPs were used to provide proof-of-concept data. Following EPO receptor-facilitated purification of target analytes from human urine, the common presence of the cysteine-flanked core structure of EMPs was exploited to generate diagnostic peptides with the aid of a nonenzymatic cleavage procedure. Sensitive detection was accomplished by targeted-SIM/data-dependent MS2 analysis. Method characterization was conducted for the EMP-based drug peginesatide concerning specificity, linearity, precision, recovery, stability, ion suppression/enhancement, and limit of detection (LOD, 0.25 ng/mL). Additionally, first data for the identification of the erythropoietin mimetic peptides EMP1 and BB68 were generated, demonstrating the multi-analyte testing capability of the presented approach.

NUCLEOSYNTHESIS IN HIGH-ENTROPY HOT BUBBLES OF SUPERNOVAE AND ABUNDANCE PATTERNS OF EXTREMELY METAL-POOR STARS

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

Izutani, Natsuko; Umeda, Hideyuki, E-mail: izutani@astron.s.u-tokyo.ac.j, E-mail: umeda@astron.s.u-tokyo.ac.j

2010-09-01

There have been suggestions that the abundance of extremely metal-poor (EMP) stars can be reproduced by hypernovae (HNe), not by normal supernovae (SNe). However, recently it was also suggested that if the innermost neutron-rich or proton-rich matter is ejected, the abundance patterns of ejected matter are changed, and normal SNe may also reproduce the observations of EMP stars. In this Letter, we calculate explosive nucleosynthesis with various Y {sub e} and entropy, and investigate whether normal SNe with this innermost matter, which we call the 'hot-bubble' component, can reproduce the abundance of EMP stars. We find that neutron-rich (Y {submore » e} = 0.45-0.49) and proton-rich (Y {sub e} = 0.51-0.55) matter can increase Zn/Fe and Co/Fe ratios as observed, but tend to overproduce other Fe-peak elements. In addition, we find that if slightly proton-rich matter with 0.50 {<=} Y {sub e} < 0.501 with s/k {sub b} {approx} 15-40 is ejected as much as {approx}0.06 M {sub sun}, even normal SNe can reproduce the abundance of EMP stars, though it requires fine-tuning of Y {sub e}. On the other hand, HNe can more easily reproduce the observations of EMP stars without fine-tuning. Our results imply that HNe are the most likely origin of the abundance pattern of EMP stars.« less

[Effects on structure and secretion of pituitary gland in rats after electromagnetic pulse exposure].

PubMed

Fang, Heng-hu; Zeng, Gui-ying; Nie, Qing; Kang, Jing-bo; Ren, Dong-qing; Zhou, Jia-xing; Li, Yun-ming

2010-12-07

To investigate the exposure effect of electromagnetic pulse (EMP) on the structure and secretion of pituitary gland in rats. Forty-eight male SD rats were randomly divided into eight groups. Four groups were subject to the EMP exposure of 200 kV/m and the others received a sham exposure. At different time points (12, 24, 48 & 96 h) post-exposure, the pathological changes of pituitary gland were observed by light and transmission electron microscope. And the serum levels of prolactin (PRL), growth hormone (GH), adrenocorticotropic hormone (ACTH), thyroid stimulating hormone (TSH) and luteinizing hormone (LH) were measured dynamically by radioimmunoassay. At 12 h post-exposure, swollen mitochondria with cristae loss, dilatation of Golgi complex and diffusive lysosomes were found in endocrine cells of pituitary gland. The above changes became gradually worse. Mitochondrial vacuolization, the formation of myelin figures, distinct dilatation of endoplasmic reticulum, the occurrence of numerous secondary lysosomes and the clustering of heterochromatin under the nuclear membranes could be observed at 48 h. These lesions were alleviated to some degree at 96 h. The serum levels of PRL and ACTH both increased significantly at 12 h (P < 0.01, P < 0.05) and returned to normal at 24 h. The level of GH decreased significantly at 12 h and then returned gradually to normal at 48 h. The level of TSH decreased at 12 h and reached the lowest point at 24 h, then returned to normal at 96 h. LH increased significantly from 24 h to 96 h. The EMP exposure of 200 kV/m may induce the changes of the structure and secretion of pituitary gland in rats.

Fabrication and surface-modification of implantable microprobes for neuroscience studies

NASA Astrophysics Data System (ADS)

Cao, H.; Nguyen, C. M.; Chiao, J. C.

2012-06-01

In this work implantable micro-probes for central nervous system (CNS) studies were developed on silicon and polyimide substrates. The probes which contained micro-electrode arrays with different surface modifications were designed for implantation in the CNS. The electrode surfaces were modified with nano-scale structures that could greatly increase the active surface area in order to enhance the electrochemical current outputs while maintaining micro-scale dimensions of the electrodes and probes. The electrodes were made of gold or platinum, and designed with different sizes. The silicon probes were modified by silicon nanowires fabricated with the vapor-liquid-solid mechanism at high temperatures. With polyimide substrates, the nanostructure modification was carried out by applying concentrated gold or silver colloid solutions onto the micro-electrodes at room temperature. The surfaces of electrodes before and after modification were observed by scanning electron microscopy. The silicon nanowire-modified surface was characterized by cyclic voltammetry. Experiments were carried out to investigate the improvement in sensing performance. The modified electrodes were tested with H2O2, electrochemical L-glutamate and dopamine. Comparisons between electrodes with and without nanostructure modification were conducted showing that the modifications have enhanced the signal outputs of the electrochemical neurotransmitter sensors.

Near infrared spectra of muscovite, Tschermak substitution, and metamorphic reaction progress: Implications for remote sensing

NASA Astrophysics Data System (ADS)

Duke, Edward F.

1994-07-01

Near infrared (NIR) spectra of Precambrian metagraywacke in the Black Hills, South Dakota, demonstrate that reflectance spectroscopy can be used to monitor progressive changes in mineral chemistry as a function of metamorphic grade. The wavelength of a combination Al-O-H absorption band in muscovite, measured using both laboratory and field-portable NIR spectrometers, shifts from 2217 nm in the biotite zone to 2199 nm in the sillimanite + K-feldspar zone. The band shift corresponds to an increase in the Alvi content of muscovite, determined by electron microprobe, and is thus a monitor of Al2Si-1(Fe,Mg)-1 (Tschermak) exchange. Spectroscopic measurements such as these are useful in the case of aluminum-deficient rocks, which lack metamorphic index minerals or appropriate assemblages for thermobarometric studies, and in low-grade rocks (subgarnet zone), which lack quantitative indicators of metamorphic grade and are too fine grained for petrographic or microprobe studies. More important, spectroscopic detection of mineral-chemical variations in metamorphic rocks provides petrologists with a tool to recover information on metamorphic reaction histories from high-spectral-resolution aircraft or satellite remote sensing data.

Design of a TEM cell EMP simulator

NASA Astrophysics Data System (ADS)

Sevat, Pete

1991-06-01

Electromagnetic pulse (EMP) simulators are designed to simulate the EMP generated by a nuclear weapon and are used to harden equipment against the effects of EMP. A transverse electromagnetic (TEM) cell is a square or rectangular coaxial transmission line tapered at each end to form a closed cell. The cell is fed at one end with a signal generator, a continuous wave or pulse generator, and terminated at the other end with a resistor equal to the characteristic impedance of the line. An advantage of the TEM cell is that the field is well characterized and reasonably uniform. A small, symmetric, TEM cell EMP simulator is described which is intended for applications such as susceptibility testing of small equipment, calibration of sensors, design and testing of countermeasures, measurement of transfer functions, and research and development. A detailed design is presented for a 50 ohm and 100 ohm TEM cell with an inner volume of 4 m(exp 3) and a test volume of 0.24 m(exp 3). The pulse generator and terminating network are integrated into the cell to form a completely shielded structure. In this way no interference from the inside of the cell to the outside, or vice versa, will occur.

78 FR 69405 - Enable Gas Transmission, LLC; Notice of Application

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-19

..., by sell and transfer from Enable to Enable Midstream Partners, LP (EMP), certain facilities and... Leedey Purification Facility and to abandon by sale to EMP the following facilities in Oklahoma: (1) The...

7 CFR 1486.402 - What are ineligible contributions?

Code of Federal Regulations, 2013 CFR

2013-01-01

... Recipient or third party, e.g., free publicity; (10) The cost of developing any application/proposal for EMP... approval of an EMP-funded project. (b) The Deputy Administrator shall determine, at his or her discretion...

1988 IEEE Annual Conference on Nuclear and Space Radiation Effects, 25th, Portland, OR, July 12-15, 1988, Proceedings

NASA Technical Reports Server (NTRS)

Coakley, Peter G. (Editor)

1988-01-01

The effects of nuclear and space radiation on the performance of electronic devices are discussed in reviews and reports of recent investigations. Topics addressed include the basic mechanisms of radiation effects, dosimetry and energy-dependent effects, sensors in and for radiation environments, EMP/SGEMP/IEMP phenomena, radiation effects on isolation technologies, and spacecraft charging and space radiation effects. Consideration is given to device radiation effects and hardening, hardness assurance and testing techniques, IC radiation effects and hardening, and single-event phenomena.

Elemental fractionation and magnetic properties of melt-based Y1Ba2Cu3Oz containing excess Tb or Pt

NASA Technical Reports Server (NTRS)

Hojaji, Hamid; Barkatt, Aaron; Hu, Shouxiang; Michael, Karen A.; Thorpe, Arthur N.; Talmy, Inna G.; Haught, Debbie A.; Alterescu, Sidney

1990-01-01

Scanning electron microscopy of certain partially melted Y-Ba-Cu-O materials containing minority metal oxide species (Y:Tb:Ba:Cu = 1:0.1:2:3 or Y:Ba:Cu with Pt impurities), accompanied by both EDX and EMP analysis, indicates that the minority species (Tb or Pt) is quantitatively concentrated in a relatively small number of 123-type grains. High magnetic susceptibility and magnetization observed for these materials indicate that such elemental distribution is not detrimental to superconducting behavior.

Efficiency at maximum power for an isothermal chemical engine with particle exchange at varying chemical potential

NASA Astrophysics Data System (ADS)

Koning, Jesper; Koga, Kenichiro; Indekeu, Joseph. O.

2017-02-01

We calculate the efficiency at maximum power (EMP) of an isothermal chemical cycle in which particle uptake occurs at a fixed chemical potential but particle release takes place at varying chemical potential. We obtain the EMP as a function of Δμ/ kT, where Δμ is the difference between the highest and lowest reservoir chemical potentials and T is the absolute temperature. In the linear response limit, Δμ ≪ kT, the EMP tends to the expected universal value 1/2.

Kinetics of B cell responses to Plasmodium falciparum erythrocyte membrane protein 1 in Ghanaian women naturally exposed to malaria parasites.

PubMed

Ampomah, Paulina; Stevenson, Liz; Ofori, Michael F; Barfod, Lea; Hviid, Lars

2014-06-01

Naturally acquired protective immunity to Plasmodium falciparum malaria takes years to develop. It relies mainly on Abs, particularly IgG specific for Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) proteins on the infected erythrocyte surface. It is only partially understood why acquisition of clinical protection takes years to develop, but it probably involves a range of immune-evasive parasite features, not least of which are PfEMP1 polymorphism and clonal variation. Parasite-induced subversion of immunological memory and expansion of "atypical" memory B cells may also contribute. In this first, to our knowledge, longitudinal study of its kind, we measured B cell subset composition, as well as PfEMP1-specific Ab levels and memory B cell frequencies, in Ghanaian women followed from early pregnancy up to 1 y after delivery. Cell phenotypes and Ag-specific B cell function were assessed three times during and after pregnancy. Levels of IgG specific for pregnancy-restricted, VAR2CSA-type PfEMP1 increased markedly during pregnancy and declined after delivery, whereas IgG levels specific for two PfEMP1 proteins not restricted to pregnancy did not. Changes in VAR2CSA-specific memory B cell frequencies showed typical primary memory induction among primigravidae and recall expansion among multigravidae, followed by contraction postpartum in all. No systematic changes in the frequencies of memory B cells specific for the two other PfEMP1 proteins were identified. The B cell subset analysis confirmed earlier reports of high atypical memory B cell frequencies among residents of P. falciparum-endemic areas, and indicated an additional effect of pregnancy. Our study provides new knowledge regarding immunity to P. falciparum malaria and underpins efforts to develop PfEMP1-based vaccines against this disease. Copyright © 2014 by The American Association of Immunologists, Inc.

Topical Treatment With an Agent Disruptive to P. acnes Biofilm Provides Positive Therapeutic Response: Results of a Randomized Clinical Trial.

PubMed

Bernhardt, Michael J; Myntti, Matthew F

2016-06-01

The traditional disease model of acne has been one of follicular plugging due to 'sticky epithelial cells' associated with increased sebum production with deep follicular anaerobic conditions favoring P. acnes- generated inflammation. P. acnes biofilms have been found more frequently in patients with acne than controls. Biofilms are genetically coded to create adhesion to the pilosebaceous unit followed by production of a mucopolysaccharide coating capable of binding to lipid surfaces. Traditional therapies for acne have involved mixtures of oral and topical antibiotics admixed with topical keratolytics and retinoids, which are aimed at traditional bacterial reduction as well as downregulating the inflammatory cascade. These approaches are limited by side effect and compliance/tolerability issues. As the P. acnes biofilm may, in fact, be the instigator of this process, we studied the use of a topical agent designed to reduce the P. acnes biofilm to see if reducing the biofilm would be therapeutically efficacious. We present data of a proprietary topical non-prescription agent with a novel pharmaco mechanism designed to attack the biofilm produced by P. acnes. Our data shows a decrease of inflammatory lesions by 44% and non-inflammatory lesions by 32% after 12 weeks and also provided for a meaningful improvement in the quality of life of the patients in the study. These improvements were achieved with a product that was not associated with burning, chafing, irritation, or erythema, which can be seen with topical treatments. It is apparent from this study that by addressing the biofilm which protects the P. acnes bacteria through the use of the Acne Gel, the incidence of acne symptoms can be greatly reduced, while having no negative impacts on the patients' skin (ClinicalTrials.gov registry number NCT02404285).

J Drugs Dermatol. 2016;15(6):677-683.

A thermal microprobe fabricated with wafer-stage processing

NASA Astrophysics Data System (ADS)

Zhang, Yongxia; Zhang, Yanwei; Blaser, Juliana; Sriram, T. S.; Enver, Ahsan; Marcus, R. B.

1998-05-01

A thermal microprobe has been designed and built for high resolution temperature sensing. The thermal sensor is a thin-film thermocouple junction at the tip of an atomic force microprobe (AFM) silicon probe needle. Only wafer-stage processing steps are used for the fabrication. For high resolution temperature sensing it is essential that the junction be confined to a short distance at the AFM tip. This confinement is achieved by a controlled photoresist coating process. Experiment prototypes have been made with an Au/Pd junction confined to within 0.5 μm of the tip, with the two metals separated elsewhere by a thin insulating oxide layer. Processing begins with double-polished, n-type, 4 in. diameter, 300-μm-thick silicon wafers. Atomically sharp probe tips are formed by a combination of dry and wet chemical etching, and oxidation sharpening. The metal layers are sputtering deposited and the cantilevers are released by a combination of KOH and dry etching. A resistively heated calibration device was made for temperature calibration of the thermal microprobe over the temperature range 25-110 °C. Over this range the thermal outputs of two microprobes are 4.5 and 5.6 μV/K and is linear. Thermal and topographical images are also obtained from a heated tungsten thin film fuse.

EMP Threats to US National Security: Congressional Responses

NASA Astrophysics Data System (ADS)

Huessy, Peter

2011-04-01

The US Congress is considering how best to respond to concerns that EMP is a real and present danger to US security. The threats come from a variety of areas: solar storms, non-nuclear EMP from man-made machines and devices; and nuclear EMP from a nuclear device exploded above CONUS or other critical areas important to the United States and its allies. Responses have to date included passage in the House of legislation to protect the electrical grid in the United States from such threats and hearings before the Homeland Security Committee. Additional efforts include examining missile defense responses, protection of the maritime domain, and hardening of US military and related civilian infrastructure. The House of Representatives has also examined what Europe, the European Union and NATO, both government and private industry, have done in these areas. Complicating matters are related issues of cyber-security and overall homeland security priorities.

EMP-induced BBB-disruption enhances drug delivery to glioma and increases treatment efficacy in rats.

PubMed

Li, Kangchu; Zhang, Keying; Xu, Shenglong; Wang, Xiaowu; Zhou, Yongchun; Zhou, Yan; Gao, Peng; Lin, Jiajin; Ding, Guirong; Guo, Guozhen

2018-01-01

Chemotherapy on gliomas is not satisfactorily efficient because the presence of blood-brain barriers (BBB) leads to inadequate exposure of tumor cells to administered drugs. In order to facilitate chemotherapeutics to penetrate BBB and increase the treatment efficacy of gliomas, electromagnetic pulse (EMP) was applied and the 1-(2-Chlorethyl)-cyclohexyl-nitrosourea (CCNU) lomustine concentration in tumor tissue, tumor size, tumor apoptosis, and side effects were measured in glioma-bearing rat model. The results showed that EMP exposure could enhance the delivery of CCNU to tumor tissue, facilitate tumor apoptosis, and inhibit tumor growth without obvious side effects. The data indicated that EMP-induced BBB disruption could enhance delivery of CCNU to glioblastoma multiforme and increase treatment efficacy in glioma-bearing rats. Bioelectromagnetics. 39:60-67, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Some factors influencing susceptibility of rainbow trout to the acute toxicity of an ethyl mercury phosphate formulation (Timsan)

USGS Publications Warehouse

Amend, Donald F.; Yasutake, William T.; Morgan, Reginald

1969-01-01

This study determined the influence of water temperature (55–68° F), dissolved oxygen (4–12 ppm), water hardness as CaCO3 (20–256 ppm), and chloride ions (to 2 mM) on the susceptibility of rainbow trout (Salmo gairdneri) to the acute toxicity of ethyl mercury phosphate (EMP). The fish were exposed for one hour to 0.125 ppm EMP, the active ingredient of Timsan, a commercial EMP formulation. The death rate because of the exposure to EMP increased with an increase in water temperature, a decrease in dissolved oxygen, and an increase in chloride ions; calcium appeared to have no effect. The effect of water temperature and dissolved oxygen was ascribed to changes in the respiration rate of the fish, and a chemical explanation is presented for the effect of chloride ions.

Impact of expression of EMP enzymes on glucose metabolism in Zymomonas mobilis.

PubMed

Chen, Rachel Ruizhen; Agrawal, Manoj; Mao, Zichao

2013-06-01

Zymomonas mobilis is the only known microorganism that utilizes the Entner-Doudoroff (ED) pathway anaerobically. In this work, we investigated whether the overexpression of a phosphofructokinase (PFK), the only missing Embden-Meyerhof-Parnas (EMP) pathway enzyme, could establish the pathway in this organism. Introduction of a pyrophosphate-dependent PFK, along with co-expression of homologous fructose-1,6-bisphosphate aldolase and triosephosphate isomerase, did not result in an EMP flux to any appreciable level. However, the metabolism of glucose was impacted significantly. Eight percent of glucose was metabolized to form a new metabolite, dihydroxyacetone. Reducing flux through the ED pathway by as much as 40 % through antisense of a key enzyme, ED aldolase, did not result in a fully functional EMP pathway, suggesting that the ED pathway, especially the lower arm, downstream from glyceraldehyde-3-phosphate, is very rigid, possibly due to redox balance.

A cross-country Exchange Market Pressure (EMP) dataset.

PubMed

Desai, Mohit; Patnaik, Ila; Felman, Joshua; Shah, Ajay

2017-06-01

The data presented in this article are related to the research article titled - "An exchange market pressure measure for cross country analysis" (Patnaik et al. [1]). In this article, we present the dataset for Exchange Market Pressure values (EMP) for 139 countries along with their conversion factors, ρ (rho). Exchange Market Pressure, expressed in percentage change in exchange rate, measures the change in exchange rate that would have taken place had the central bank not intervened. The conversion factor ρ can interpreted as the change in exchange rate associated with $1 billion of intervention. Estimates of conversion factor ρ allow us to calculate a monthly time series of EMP for 139 countries. Additionally, the dataset contains the 68% confidence interval (high and low values) for the point estimates of ρ 's. Using the standard errors of estimates of ρ 's, we obtain one sigma intervals around mean estimates of EMP values. These values are also reported in the dataset.

Sub-nanosecond dynamics in low-dimensional systems

NASA Astrophysics Data System (ADS)

Armstrong-Brown, Alistair

The sub-nanosecond dynamics of a two-dimensional electron gas (2DEG) are studied in conditions of high fields and low temperatures. Three main regimes are identified. Firstly, the propagation of sub-nanosecond, or GHz, signals in a 2DEG waveguide at low temperature (2 K) and high magnetic field (9 T). Here we show that the 2DEG waveguide can be fully parameterised by the Hall resistance and a new 'microwave scaling constant'. Secondly, the physics of plasmons confined at the edge and in a magnetic field (9 T): edge magnetoplasmons (EMPs). Here we resolve multiple plasmon modes, where as well as the standard EMP resonances, we discover additional lower frequency modes, which could be related to transverse acoustic excitations. Thirdly, tunneling into microwave induced resistance oscillation (MIRO) states at low temperatures (50 mK). By using a novel cleaved edge overgrown (CEO) technique we are able to identify the role of photon assisted tunneling (PAT) in the formation of MIROs. These experimental results were obtained by developing new techniques combining microwaves, low temperatures, 2DEGs and high magnetic fields, which required the design and fabrication of several novel probes for these regimes.

On the Validity of Certain Approximations Used in the Modeling of Nuclear EMP

DOE PAGES

Farmer, William A.; Cohen, Bruce I.; Eng, Chester D.

2016-04-01

The legacy codes developed for the modeling of EMP, multiple scattering of Compton electrons has typically been modeled by the obliquity factor. A recent publication has examined this approximation in the context of the generated Compton current [W. A. Farmer and A. Friedman, IEEE Trans. Nucl. Sc. 62, 1695 (2015)]. Here, this previous analysis is extended to include the generation of the electromagnetic fields. Obliquity factor predictions are compared with Monte-Carlo models. In using a Monte-Carlo description of scattering, two distributions of scattering angles are considered: Gaussian and a Gaussian with a single-scattering tail. Additionally, legacy codes also neglect themore » radial derivative of the backward-traveling wave for computational efficiency. The neglect of this derivative improperly treats the backward-traveling wave. Moreover, these approximations are examined in the context of a high-altitude burst, and it is shown that in comparison to more complete models, the discrepancy between field amplitudes is roughly two to three percent and between rise-times, 10%. Finally, it is concluded that the biggest factor in determining the rise time of the signal is not the dynamics of the Compton current, but is instead the conductivity.« less

Fluoride concentration in dentine as a biomarker of fluoride intake in European roe deer (Capreolus capreolus) - an electron-microprobe study.

PubMed

Richter, Heiko; Kierdorf, Uwe; Richards, Alan; Melcher, Frank; Kierdorf, Horst

2011-08-01

Fluoride concentration in dentine has been recommended as the best marker for the level of chronic fluoride intake and the most suitable indicator of an individual's total body burden of fluoride. We analysed fluoride concentrations in the dentine of cheek teeth of European roe deer from fluoride-polluted habitats to retrospectively assess the level of fluoride uptake into the tissue. Thereby, we tested the hypothesis of the existence of mechanisms that limit fluoride intake of individuals and fluoride exposure of forming dental hard tissues during the late foetal and early postnatal periods in the species. Using electron-microprobe analysis, fluoride profiles were obtained on sectioned P(4)s, M(1)s, and M(3)s from individuals exhibiting pronounced dental fluorosis. Fluoride concentrations were compared between early formed (peripheral) and late-formed (juxtapulpal) dentine both within single teeth and amongst the three different teeth studied. Peripheral dentine of the M(1), which is formed during the late foetal and early postnatal periods, exhibited markedly lower fluoride concentrations than juxtapulpal dentine of the same tooth and both, peripheral and juxtapulpal dentine of P(4) and M(3) that are formed post-weaning. Our study provides strong support for the hypothesis that in the European roe deer the prenatal and early postnatal (pre-weaning) stages of dental development are (largely) protected against exposure to excess fluoride. This is attributed to the operation of certain protective mechanisms during these periods. Copyright © 2011 Elsevier Ltd. All rights reserved.

Moessbauer and Electron Microprobe Studies of Density Separates of Martian Nakhlite Mil03346: Implications for Interpretation of Moessbauer Spectra Acquired by the Mars Exploration Rovers

NASA Technical Reports Server (NTRS)

Morris, R. V.; McKay, G. A.; Agresti, D. G.; Li, Loan

2008-01-01

Martian meteorite MIL03346 is described as an augite-rich cumulate rock with approx.80%, approx.3%, and approx.21% modal phase proportions of augite (CPX), olivine and glassy mesostasis, respectively, and is classified as a nakhlite [1]. The Mossbauer spectrum for whole rock (WR) MIL 03346 is unusual for Martian meteorites in that it has a distinct magnetite subspectrum (7% subspectral area) [2]. The meteorite also has products of pre-terrestrial aqueous alteration ("iddingsite") that is associated primarily with the basaltic glass and olivine. The Mossbauer spectrometers on the Mars Exploration Rovers have measured the Fe oxidation state and the Fe mineralogical composition of rocks and soils on the planet s surface since their landing in Gusev Crater and Meridiani Planum in January, 2004 [3,4]. The MIL 03346 meteorite provides an opportunity to "ground truth" or refine Fe phase identifications. This is particularly the case for the so-called "nanophase ferric oxide" (npOx) component. NpOx is a generic name for a ferric rich product of oxidative alteration. On Earth, where we can take samples apart and study individual phases, examples of npOx include ferrihydrite, schwertmannite, akagaaneite, and superparamagnetic (small particle) goethite and hematite. It is also possible for ferric iron to be associated to some unknown extent with igneous phases like pyroxene. We report here an electron microprobe (EMPA) and Moessbauer (MB) study of density separates of MIL 03346. The same separates were used for isotopic studies by [5]. Experimental techniques are described by [6,7].

Use of electron microprobe x-ray analysis for determination of low calcium concentrations across leaves deficient in calcium

NASA Technical Reports Server (NTRS)

Barta, D. J.; Tibbitts, T. W.

1991-01-01

An electron microprobe with wavelength-dispersive x-ray spectrometry (WDS) was found to be useful for the determination of Ca concentrations in leaf tissue deficient in Ca. WDS effectively detected Ca concentrations as low as 0.2 mg/g dry wt in the presence of high levels of K and Mg (120 and 50 mg/g dry wt, respectively). Leaf specimens were prepared for analysis by quick-freezing in liquid nitrogen and freeze-drying at -20 degrees C to maintain elemental integrity within the tissue. Because dry material was analyzed, sample preparation was simple and samples could be stored for long periods before analysis. A large beam diameter of 50 gm was used to minimize tissue damage under the beam and analyze mineral concentrations within several cells at one time. Beam penetration was between 50 and 55 microns, approximately one-third of the thickness of the leaf. For analysis of concentrations in interveinal areas, analyses directed into the abaxial epidermis were found most useful. However, because of limited beam penetration, analyses of veinal areas would require use of cross sections [correction of crosssections]. Solid mineral standards were used for instrument standardization. To prevent measurement errors resulting from differences between the matrix of the mineral standards and the analyzed tissue, concentrations in leaves were corrected using gelatin standards prepared and analyzed under the same conditions. WDS was found to be useful for documenting that very low Ca levels occur in specific areas of lettuce leaves exhibiting the Ca deficiency injury termed tipburn.

Approximate chemical analysis of volcanic glasses using Raman spectroscopy

PubMed Central

Morgavi, Daniele; Hess, Kai‐Uwe; Neuville, Daniel R.; Borovkov, Nikita; Perugini, Diego; Dingwell, Donald B.

2015-01-01

The effect of chemical composition on the Raman spectra of a series of natural calcalkaline silicate glasses has been quantified by performing electron microprobe analyses and obtaining Raman spectra on glassy filaments (~450 µm) derived from a magma mingling experiment. The results provide a robust compositionally‐dependent database for the Raman spectra of natural silicate glasses along the calcalkaline series. An empirical model based on both the acquired Raman spectra and an ideal mixing equation between calcalkaline basaltic and rhyolitic end‐members is constructed enabling the estimation of the chemical composition and degree of polymerization of silicate glasses using Raman spectra. The model is relatively insensitive to acquisition conditions and has been validated using the MPI‐DING geochemical standard glasses1 as well as further samples. The methods and model developed here offer several advantages compared with other analytical and spectroscopic methods such as infrared spectroscopy, X‐ray fluorescence spectroscopy, electron and ion microprobe analyses, inasmuch as Raman spectroscopy can be performed with a high spatial resolution (1 µm2) without the need for any sample preparation as a nondestructive technique. This study represents an advance in efforts to provide the first database of Raman spectra for natural silicate glasses and yields a new approach for the treatment of Raman spectra, which allows us to extract approximate information about the chemical composition of natural silicate glasses using Raman spectroscopy. We anticipate its application in handheld in situ terrestrial field studies of silicate glasses under extreme conditions (e.g. extraterrestrial and submarine environments). © 2015 The Authors Journal of Raman Spectroscopy Published by John Wiley & Sons Ltd PMID:27656038

Effects of electromagnetic pulse on polydactyly of mouse fetuses.

PubMed

Yang, Ming-Juan; Liu, Jun-Ye; Wang, Ya-Feng; Lang, Hai-Yang; Miao, Xia; Zhang, Li-Yan; Zeng, Li-Hua; Guo, Guo-Zhen

2013-07-01

There is an increasing public concern regarding potential health impacts from electromagnetic radiation exposure. Embryonic development is sensitive to the external environment, and limb development is vital for life quality. To determine the effects of electromagnetic pulse (EMP) on polydactyly of mouse fetuses, pregnant mice were sham-exposed or exposed to EMP (400 kV/m with 400 pulses) from Days 7 to 10 of pregnancy (Day 0 = day of detection of vaginal plug). As a positive control, mice were treated with 5-bromodeoxyuridine on Days 9 and 10. On Days 11 or 18, the fetuses were isolated. Compared with the sham-exposed group, the group exposed to EMP had increased rates of polydactyly fetuses (5.1% vs. 0.6%, P < 0.05) and abnormal gene expression (22.2% vs. 2.8%, P < 0.05). Ectopic expression of Fgf4 was detected in the apical ectodermal ridge, whereas overexpression and ectopic expression of Shh were detected in the zone of polarizing activity of limbs in the EMP-exposed group and in the positive control group. However, expression of Gli3 decreased in mesenchyme cells in those two groups. The percentages of programmed cell death of limbs in EMP-exposed and positive control group were decreased (3.57% and 2.94%, respectively, P < 0.05, compared with 7.76% in sham-exposed group). In conclusion, polydactyly induced by EMP was accompanied by abnormal expression of the above-mentioned genes and decreased percentage of programmed cell death during limb development. Copyright © 2013 Elsevier Inc. All rights reserved.

The Severity of Plasmodium falciparum Infection Is Associated with Transcript Levels of var Genes Encoding Endothelial Protein C Receptor-Binding P. falciparum Erythrocyte Membrane Protein 1.

PubMed

Mkumbaye, Sixbert I; Wang, Christian W; Lyimo, Eric; Jespersen, Jakob S; Manjurano, Alphaxard; Mosha, Jacklin; Kavishe, Reginald A; Mwakalinga, Steven B; Minja, Daniel T R; Lusingu, John P; Theander, Thor G; Lavstsen, Thomas

2017-04-01

By attaching infected erythrocytes to the vascular lining, Plasmodium falciparum parasites leave blood circulation and avoid splenic clearance. This sequestration is central to pathogenesis. Severe malaria is associated with parasites expressing an antigenically distinct P. falciparum erythrocyte membrane protein 1 (PfEMP1) subset mediating binding to endothelial receptors. Previous studies indicate that PfEMP1 adhesins with so-called CIDRα1 domains capable of binding endothelial protein C receptor (EPCR) constitute the PfEMP1 subset associated with severe pediatric malaria. To analyze the relative importance of different subtypes of CIDRα1 domains, we compared Pf emp1 transcript levels in children with severe malaria (including 9 fatal and 114 surviving cases), children hospitalized with uncomplicated malaria ( n = 42), children with mild malaria not requiring hospitalization ( n = 10), and children with parasitemia and no ongoing fever ( n = 12). High levels of transcripts encoding EPCR-binding PfEMP1 were found in patients with symptomatic infections, and the abundance of these transcripts increased with disease severity. The compositions of CIDRα1 subtype transcripts varied markedly between patients, and none of the subtypes were dominant. Transcript-level analyses targeting other domain types indicated that subtypes of DBLβ or DBLζ domains might mediate binding phenomena that, in conjunction with EPCR binding, could contribute to pathogenesis. These observations strengthen the rationale for targeting the PfEMP1-EPCR interaction by vaccines and adjunctive therapies. Interventions should target EPCR binding of all CIDRα1 subtypes. Copyright © 2017 American Society for Microbiology.

Association between vascular access failure and microparticles in hemodialysis patients

PubMed Central

Ryu, Jung-Hwa; Lim, Su-Young; Ryu, Dong-Ryeol; Kang, Duk-Hee; Choi, Kyu Bok; Kim, Seung-Jung

2012-01-01

Background Vascular access failure, a major cause of morbidity in hemodialysis (HD) patients, occurs mainly at stenotic endothelium following an acute thrombotic event. Microparticles (MPs) are fragments derived from injured cell membrane and are closely associated with coagulation and vascular inflammatory responses. Methods We investigated the relationship between levels of circulating MPs and vascular access patency in HD patients. A total of 82 HD patients and 28 healthy patients were enrolled. We used flow cytometry to measure endothelial MPs (EMPs) identified by CD31+CD42− or CD51+ and platelet-derived MPs (PMPs) identified by CD31+CD42+ in plasma samples of participants. Vascular access patency was defined as an interval from the time of access formation to the time of first access stenosis in each patient. MP counts were compared according to access patent duration. Results The levels of EMP (both CD31+CD42− and CD51+) and CD31+CD42+PMP were significantly higher in patients than in healthy participants. Levels of CD31+CD42−EMP and CD31+CD42+PMP showed a positive correlation. In non-diabetic HD patients, CD31+CD42−EMPs and CD31+CD42+PMPs were more elevated in the shorter access survival group (access survival <1 year) than in the longer survival group (access survival ≥ 4 years). Conclusion Elevated circulating EMP or PMP counts are influenced by end-stage renal disease and increased levels of EMP and PMP may be associated with vascular access failure in HD patients. PMID:26889407

Ethanol Extract of Mylabris phalerata Inhibits M2 Polarization Induced by Recombinant IL-4 and IL-13 in Murine Macrophages

PubMed Central

Chung, Hwan-Suck; Lee, Bong-Seon

2017-01-01

Mylabris phalerata (MP) is an insect used in oriental herbal treatments for tumor, tinea infections, and stroke. Recent studies have shown that tumor-associated macrophages (TAM) have detrimental roles such as tumor progression, angiogenesis, and metastasis. Although TAM has phenotypes and characteristics in common with M2-polarized macrophages, M1 macrophages have tumor suppression and immune stimulation effects. Medicines polarizing macrophages to M1 have been suggested to have anticancer effects via the modulation of the tumor microenvironment. In this line, we screened oriental medicines to find M1 polarizing medicines in M2-polarized macrophages. Among approximately 400 types of oriental medicine, the ethanol extract of M. phalerata (EMP) was the most proficient in increasing TNF-α secretion in M2-polarized macrophages and TAM. Although EMP enhanced the levels of an M1 cytokine (TNF-α) and a marker (CD86), it significantly reduced the levels of an M2 marker (arginase-1) in M2-polarized macrophages. In addition, EMP-treated macrophages increased the levels of M1 markers (Inos and Tnf-α) and reduced those of the enhanced M2 markers (Fizz-1, Ym-1, and arginase-1). EMP-treated macrophages significantly reduced Lewis lung carcinoma cell migration in a transwell migration assay and inhibited EL4-luc2 lymphoma proliferation. In our mechanism study, EMP was found to inhibit STAT3 phosphorylation in M2-polarized macrophages. These results suggest that EMP is effective in treating TAM-mediated tumor progression and metastasis. PMID:28811825

Evasion of Immunity to Plasmodium falciparum: Rosettes of Blood Group A Impair Recognition of PfEMP1

PubMed Central

Moll, Kirsten; Palmkvist, Mia; Ch'ng, Junhong; Kiwuwa, Mpungu Steven; Wahlgren, Mats

2015-01-01

The ABO blood group antigens are expressed on erythrocytes but also on endothelial cells, platelets and serum proteins. Notably, the ABO blood group of a malaria patient determines the development of the disease given that blood group O reduces the probability to succumb in severe malaria, compared to individuals of groups A, B or AB. P. falciparum rosetting and sequestration are mediated by PfEMP1, RIFIN and STEVOR, expressed at the surface of the parasitized red blood cell (pRBC). Antibodies to these antigens consequently modify the course of a malaria infection by preventing sequestration and promoting phagocytosis of pRBC. Here we have studied rosetting P. falciparum and present evidence of an immune evasion mechanism not previously recognized. We find the accessibility of antibodies to PfEMP1 at the surface of the pRBC to be reduced when P. falciparum forms rosettes in blood group A RBC, as compared to group O RBC. The pRBC surrounds itself with tightly bound normal RBC that makes PfEMP1 inaccessible to antibodies and clearance by the immune system. Accordingly, pRBC of in vitro cloned P. falciparum devoid of ABO blood group dependent rosetting were equally well detected by anti-PfEMP1 antibodies, independent of the blood group utilized for their propagation. The pathogenic mechanisms underlying the severe forms of malaria may in patients of blood group A depend on the ability of the parasite to mask PfEMP1 from antibody recognition, in so doing evading immune clearance. PMID:26714011

7 CFR 1486.100 - What is the Emerging Markets Program?

Code of Federal Regulations, 2012 CFR

2012-01-01

... What is the Emerging Markets Program? (a) The principal purpose of the EMP is to assist U.S. entities... training, business workshops, and similar undertakings. (b) The EMP may be used to support exports of U.S...

7 CFR 1486.100 - What is the Emerging Markets Program?

Code of Federal Regulations, 2014 CFR

2014-01-01

... What is the Emerging Markets Program? (a) The principal purpose of the EMP is to assist U.S. entities... training, business workshops, and similar undertakings. (b) The EMP may be used to support exports of U.S...

7 CFR 1486.100 - What is the Emerging Markets Program?

Code of Federal Regulations, 2013 CFR

2013-01-01

... What is the Emerging Markets Program? (a) The principal purpose of the EMP is to assist U.S. entities... training, business workshops, and similar undertakings. (b) The EMP may be used to support exports of U.S...

Final report on low-dose estramustine phosphate (EMP) monotherapy and very low-dose EMP therapy combined with LH-RH agonist for previously untreated advanced prostate cancer.

PubMed

Kitamura, T; Suzuki, M; Nishimatsu, H; Kurosaki, T; Enomoto, Y; Fukuhara, H; Kume, H; Takeuchi, T; Miao, L; Jiangang, H; Xiaoqiang, L

2010-01-01

In order to assess the efficacy and toxicity of oral estramustine phosphate (EMP) administration, low-dose EMP monotherapy (study 1) and very low-dose EMP therapy with luteinizing hormone-releasing hormone (LH-RH) agonist (study 2) were conducted in previously untreated prostate cancer and long-term outcomes were compared between the 2 study groups. Studies 1 and 2 were independently performed beginning in June 1999 and November 2001, respectively. Study 1 was composed of 87 patients including 85 assessable patients. All 108 patients recruited for study 2 were assessable. Low-dose EMP monotherapy (2 capsules/day or 280 mg/day) was used in study 1 and very low-dose EMP (1 capsule/day or 140 mg/day) combined with LH-RH agonist was adopted in study 2. Overall prostate specific antigen (PSA) -response rates in studies 1 and 2 were 92.3% and 94.2%, respectively, and overall toxicity rates were 54.1% and 38.9%, respectively. EMP discontinuation due to side effects was encountered more often in study 1 (45.9%) than in study 2 (27.8%). Among the adverse side effects gastrointestinal toxicity was most prevalent in both studies. One patient died of acute pulmonary embolism in study 1, but no one died in study 2. There were 6 cancer deaths in the gastrointestinal tract in study 1 but only 2 cancer deaths in study 2. Our data indicate that the overall PSA response rate was comparable between both studies. However, rates in overall toxicity and drug discontinuation were higher in study 1 than in study 2. We consider that study 2 is more promising for the treatment of previously untreated advanced prostate cancer, although the rate of adverse side effects is still high as compared with other hormonal therapies. In order to overcome the high toxicity rate, especially the gastrointestinal toxicity, we recently elaborated a method employing tailor-made medicine using SNPs of 1A1 gene in cytochrome P-450 for decreasing the rate of gastrointestinal toxicity. Using this method of patient selection, study 3 has been successfully launched on September 2005 with high drug compliance. Better clinical results are being accumulated.

Modelling and interpreting biologically crusted dryland soil sub-surface structure using automated micropenetrometry

NASA Astrophysics Data System (ADS)

Hoon, Stephen R.; Felde, Vincent J. M. N. L.; Drahorad, Sylvie L.; Felix-Henningsen, Peter

2015-04-01

Soil penetrometers are used routinely to determine the shear strength of soils and deformable sediments both at the surface and throughout a depth profile in disciplines as diverse as soil science, agriculture, geoengineering and alpine avalanche-safety (e.g. Grunwald et al. 2001, Van Herwijnen et al. 2009). Generically, penetrometers comprise two principal components: An advancing probe, and a transducer; the latter to measure the pressure or force required to cause the probe to penetrate or advance through the soil or sediment. The force transducer employed to determine the pressure can range, for example, from a simple mechanical spring gauge to an automatically data-logged electronic transducer. Automated computer control of the penetrometer step size and probe advance rate enables precise measurements to be made down to a resolution of 10's of microns, (e.g. the automated electronic micropenetrometer (EMP) described by Drahorad 2012). Here we discuss the determination, modelling and interpretation of biologically crusted dryland soil sub-surface structures using automated micropenetrometry. We outline a model enabling the interpretation of depth dependent penetration resistance (PR) profiles and their spatial differentials using the model equations, σ {}(z) ={}σ c0{}+Σ 1n[σ n{}(z){}+anz + bnz2] and dσ /dz = Σ 1n[dσ n(z) /dz{} {}+{}Frn(z)] where σ c0 and σ n are the plastic deformation stresses for the surface and nth soil structure (e.g. soil crust, layer, horizon or void) respectively, and Frn(z)dz is the frictional work done per unit volume by sliding the penetrometer rod an incremental distance, dz, through the nth layer. Both σ n(z) and Frn(z) are related to soil structure. They determine the form of σ {}(z){} measured by the EMP transducer. The model enables pores (regions of zero deformation stress) to be distinguished from changes in layer structure or probe friction. We have applied this method to both artificial calibration soils in the laboratory, and in-situ field studies. In particular, we discuss the nature and detection of surface and buried (fossil) subsurface Biological Soil Crusts (BSCs), voids, macroscopic particles and compositional layers. The strength of surface BSCs and the occurrence of buried BSCs and layers has been detected at sub millimetre scales to depths of 40mm. Our measurements and field observations of PR show the importance of morphological layering to overall BSC functions (Felde et al. 2015). We also discuss the effect of penetrometer shaft and probe-tip profiles upon the theoretical and experimental curves, EMP resolution and reproducibility, demonstrating how the model enables voids, buried biological soil crusts, exotic particles, soil horizons and layers to be distinguished one from another. This represents a potentially important contribution to advancing understanding of the relationship between BSCs and dryland soil structure. References: Drahorad SL, Felix-Henningsen P. (2012) An electronic micropenetrometer (EMP) for field measurements of biological soil crust stability, J. Plant Nutr. Soil Sci., 175, 519-520 Felde V.J.M.N.L., Drahorad S.L., Felix-Henningsen P., Hoon S.R. (2015) Ongoing oversanding induces biological soil crust layering - a new approach for BSC structure elucidation determined from high resolution penetration resistance data (submitted) Grunwald, S., Rooney D.J., McSweeney K., Lowery B. (2001) Development of pedotransfer functions for a profile cone penetrometer, Geoderma, 100, 25-47 Van Herwijnen A., Bellaire S., Schweizer J. (2009) Comparison of micro-structural snowpack parameters derived from penetration resistance measurements with fracture character observations from compression tests, Cold Regions Sci. {& Technol.}, 59, 193-201

Formation of the lamellar structure in Group IA and IIID iron meteorites

NASA Technical Reports Server (NTRS)

Kowalik, J. A.; Williams, D. B.; Goldstein, J. I.

1988-01-01

Analytical EM, light microscopy, and electron microprobe analysis are used to study the lamellar plessite structure of Group IA and IIID iron meteorites. The alpha lamellae in IIID structures contained a compositional gradient from 6.1 + or - 0.7 wt pct Ni at the center of the alpha lamellae to 3.6 + or - 0.5 wt pct at the alpha/gamma interface. For the Group IA irons, compositions of 4 wt pct Ni in alpha and about 48 wt pct Ni in gamma are found. Convergent beam electron diffraction was used to characterize the orientation relations at the alpha/gamma interface in the lamellar regions of both Group IA and IIID. The phase transformations responsible for the observed lamellar structure in the IA and IIID chemical groups were also investigated.

Electrodeposition of actinide compounds from an aqueous ammonium acetate matrix. Experimental development and optimization

DOE PAGES

Boll, Rose Ann; Matos, Milan; Torrico, Matthew N.

2015-03-27

Electrodeposition is a technique that is routinely employed in nuclear research for the preparation of thin solid films of actinide materials which can be used in accelerator beam bombardments, irradiation studies, or as radioactive sources. The present study investigates the deposition of both lanthanides and actinides from an aqueous ammonium acetate electrolyte matrix. Electrodepositions were performed primarily on stainless steel disks; with yield analysis evaluated using -spectroscopy. Experimental parameters were studied and modified in order to optimize the uniformity and adherence of the deposition while maximizing the yield. The initial development utilized samarium as the plating material, with and withoutmore » a radioactive tracer. As a result, surface characterization studies were performed by scanning electron microscopy, electron microprobe analysis, radiographic imaging, and x-ray diffraction.« less

Examination of Laser Microprobe Vacuum Ultraviolet Ionization Mass Spectrometry with Application to Mapping Mars Returned Samples

NASA Astrophysics Data System (ADS)

Burton, A. S.; Berger, E. L.; Locke, D. R.; Lewis, E. K.; Moore, J. F.

2018-04-01

Laser microprobe of surfaces utilizing a two laser setup whereby the desorption laser threshold is lowered below ionization, and the resulting neutral plume is examined using 157nm Vacuum Ultraviolet laser light for mass spec surface mapping.

A study of GeV proton microprobe lens system designs with normal magnetic quadrupole

NASA Astrophysics Data System (ADS)

Dou, Yanxin; Jamieson, David N.; Liu, Jianli; Li, Liyi

2017-12-01

High energy proton irradiation has many applications to the study of radiation effects in semiconductor devices, biological tissues, proton tomography and space science. Many applications could be extended and enhanced by use of a high energy proton microprobe. However the design of a GeV proton microprobe must address significant challenges including beam collimation that minimizes ion scattering and the probe forming lens system for ions of high rigidity. Here we address the probe forming lens system design subject to several practical constraints including the use of non-superconducting normal magnetic quadrupole lenses, the ability to focus 1-5 GeV protons into 5 μm diameter microprobes and compatibility with the beam parameters of GeV proton accelerators. We show that 2, 3 and 4 lens systems of lenses with effective lengths up to 0.63 m can be employed for this purpose with a demagnification up to 58 and investigate the probe size limitations from beam brightness, lens aberrations and machining precision.

A microprobe for parallel optical and electrical recordings from single neurons in vivo.

PubMed

LeChasseur, Yoan; Dufour, Suzie; Lavertu, Guillaume; Bories, Cyril; Deschênes, Martin; Vallée, Réal; De Koninck, Yves

2011-04-01

Recording electrical activity from identified neurons in intact tissue is key to understanding their role in information processing. Recent fluorescence labeling techniques have opened new possibilities to combine electrophysiological recording with optical detection of individual neurons deep in brain tissue. For this purpose we developed dual-core fiberoptics-based microprobes, with an optical core to locally excite and collect fluorescence, and an electrolyte-filled hollow core for extracellular single unit electrophysiology. This design provides microprobes with tips < 10 μm, enabling analyses with single-cell optical resolution. We demonstrate combined electrical and optical detection of single fluorescent neurons in rats and mice. We combined electrical recordings and optical Ca²(+) measurements from single thalamic relay neurons in rats, and achieved detection and activation of single channelrhodopsin-expressing neurons in Thy1::ChR2-YFP transgenic mice. The microprobe expands possibilities for in vivo electrophysiological recording, providing parallel access to single-cell optical monitoring and control.

Advanced imaging approaches for characterizing nanoparticle delivery and dispersion in skin (Conference Presentation)

NASA Astrophysics Data System (ADS)

Prow, Tarl W.; Yamada, Miko; Dang, Nhung; Evans, Conor L.

2017-02-01

The purpose of this research was to develop advanced imaging approaches to characterise the combination of elongated silica microparticles (EMP) and nanoparticles to control topical delivery of drugs and peptides. The microparticles penetrate through the epidermis and stop at the dermal-epidermal junction (DEJ). In this study we incorporated a fluorescent lipophilic dye, DiI, as a hydrophobic drug surrogate into the nanoparticle for visualization with microscopy. In another nanoparticle-based approach we utilized a chemically functionalized melanin nanoparticle for peptide delivery. These nanoparticles were imaged by coherent anti-Stoke Raman scattering (CARS) microscopy to characterize the delivery of these nanoparticles into freshly excised human skin. We compared four different coating approaches to combine EMP and nanoparticles. These data showed that a freeze-dried formulation with cross-linked alginate resulted in 100% of the detectable nanoparticle retained on the EMP. When this dry form of EMP-nanoparticle was applied to excised, living human abdominal skin, the EMP penetrated to the DEJ followed by controlled release of the nanoparticles. This formulation resulted in a sustained release profile, whereas a freeze-dried formulation without crosslinking showed an immediate burst-type release profile. These data show that advanced imaging techniques can give unique, label free data that shows promise for clinical investigations.