Data report for onshore-offshore wide-angle seismic recordings in the Bering-Chukchi Sea, Western Alaska and eastern Siberia

USGS Publications Warehouse

Brocher, Thomas M.; Allen, Richard M.; Stone, David B.; Wolf, Lorraine W.; Galloway, Brian K.

1995-01-01

This report presents fourteen deep-crustal wide-angle seismic reflection and refraction profiles recorded onland in western Alaska and eastern Siberia from marine air gun sources in the Bering-Chukchi Seas. During a 20-day period in August, 1994, the R/V Ewing acquired two long (a total of 3754 km) deep-crustal seismic-reflection profiles on the continental shelf of the Bering and Chukchi Seas, in a collaborative project between Stanford University and the United States Geological Survey (USGS). The Ewing's 137.7 liter (8355 cu. in.) air gun array was the source for both the multichannel reflection and the wide-angle seismic data. The Ewing, operated by the Lamont-Doherty Earth Observatory, steamed northward from Nunivak Island to Barrow, and returned, firing the air gun array at intervals of either 50 m or 75 m. About 37,700 air gun shots were fired along the northward directed Lines 1 and 2, and more than 40,000 air gun shots were fired along the southward directed Line 3. The USGS and the University of Alaska, Fairbanks (UAF), deployed an array of twelve 3-component REFTEK and PDAS recorders in western Alaska and eastern Siberia which continuously recorded the air gun signals fired during the northward bound Lines 1 and 2. Seven of these recorders also continuously recorded the southward bound Line 3. These wide-angle seismic data were acquired to: (1) image reflectors in the upper to lower crust, (2) determine crustal and upper mantle refraction velocities, and (3) provide important constraints on the geometry of the Moho along the seismic lines. In this report, we describe the land recording of wide-angle data conducted by the USGS and the UAF, describe in detail how the wide-angle REFTEK and PDAS data were reduced to common receiver gather seismic sections, and illustrate the wide-angle seismic data obtained by the REFTEKs and PDAS's. Air gun signals were observed to ranges in excess of 400 km, and crustal and upper /mantle refractions indicate substantial variation in the crustal thickness along the transect.

78 FR 55014 - Machine Guns, Destructive Devices and Certain Other Firearms; Background Checks for Responsible...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-09

... No. ATF 41P; AG Order No. 3398-2013] RIN 1140-AA43 Machine Guns, Destructive Devices and Certain..., exportation, transfer, taxing, identification, registration of, and the dealing in, machine guns, destructive... section 922(g)(5)(B) of the Gun Control Act, 18 U.S.C. 922(g)(5)(B), it generally is unlawful for any...

40 CFR 63.11177 - What records must I keep?

Code of Federal Regulations, 2010 CFR

2010-07-01

....11173(e)(3)(i). (c) Documentation from the spray gun manufacturer that each spray gun with a cup... operation, you must keep the records specified in paragraphs (e) through (g) of this section, as applicable... spray gun, electrostatic application, airless spray gun, or air assisted airless spray gun, has been...

Characteristic Analysis of Air-gun Source Wavelet based on the Vertical Cable Data

NASA Astrophysics Data System (ADS)

Xing, L.

2016-12-01

Air guns are important sources for marine seismic exploration. Far-field wavelets of air gun arrays, as a necessary parameter for pre-stack processing and source models, plays an important role during marine seismic data processing and interpretation. When an air gun fires, it generates a series of air bubbles. Similar to onshore seismic exploration, the water forms a plastic fluid near the bubble; the farther the air gun is located from the measurement, the more steady and more accurately represented the wavelet will be. In practice, hydrophones should be placed more than 100 m from the air gun; however, traditional seismic cables cannot meet this requirement. On the other hand, vertical cables provide a viable solution to this problem. This study uses a vertical cable to receive wavelets from 38 air guns and data are collected offshore Southeast Qiong, where the water depth is over 1000 m. In this study, the wavelets measured using this technique coincide very well with the simulated wavelets and can therefore represent the real shape of the wavelets. This experiment fills a technology gap in China.

GUN4-Protoporphyrin IX Is a Singlet Oxygen Generator with Consequences for Plastid Retrograde Signaling*

PubMed Central

Tarahi Tabrizi, Shabnam; Sawicki, Artur; Zhou, Shuaixiang; Luo, Meizhong; Willows, Robert D.

2016-01-01

The genomes uncoupled 4 (GUN4) protein is a nuclear-encoded, chloroplast-localized, porphyrin-binding protein implicated in retrograde signaling between the chloroplast and nucleus, although its exact role in this process is still unclear. Functionally, it enhances Mg-chelatase activity in the chlorophyll biosynthesis pathway. Because GUN4 is present only in organisms that carry out oxygenic photosynthesis and because it binds protoporphyrin IX (PPIX) and Mg-PPIX, it has been suggested that it prevents production of light- and PPIX- or Mg-PPIX-dependent reactive oxygen species. A chld-1/GUN4 mutant with elevated PPIX has a light-dependent up-regulation of GUN4, implicating this protein in light-dependent sensing of PPIX, with the suggestion that GUN4 reduces PPIX-generated singlet oxygen, O2(a1Δg), and subsequent oxidative damage (Brzezowski, P., Schlicke, H., Richter, A., Dent, R. M., Niyogi, K. K., and Grimm, B. (2014) Plant J. 79, 285–298). In direct contrast, our results show that purified GUN4 and oxidatively damaged ChlH increase the rate of PPIX-generated singlet oxygen production in the light, by a factor of 5 and 10, respectively, when compared with PPIX alone. Additionally, the functional GUN4-PPIX-ChlH complex and ChlH-PPIX complexes generate O2(a1Δg) at a reduced rate when compared with GUN4-PPIX. As O2(a1Δg) is a potential plastid-to-nucleus signal, possibly through second messengers, light-dependent O2(a1Δg) generation by GUN4-PPIX is proposed to be part of a signal transduction pathway from the chloroplast to the nucleus. GUN4 thus senses the availability and flux of PPIX through the chlorophyll biosynthetic pathway and also modulates Mg-chelatase activity. The light-dependent O2(a1Δg) generation from GUN4-PPIX is thus proposed as the first step in retrograde signaling from the chloroplast to the nucleus. PMID:26969164

High Current, High Density Arc Plasma as a New Source for WiPAL

NASA Astrophysics Data System (ADS)

Waleffe, Roger; Endrizzi, Doug; Myers, Rachel; Wallace, John; Clark, Mike; Forest, Cary; WiPAL Team

2016-10-01

The Wisconsin Plasma Astrophysics Lab (WiPAL) has installed a new array of nineteen plasma sources (plasma guns) on its 3 m diameter, spherical vacuum vessel. Each gun is a cylindrical, molybdenum, washer-stabilized, arc plasma source. During discharge, the guns are maintained at 1.2 kA across 100 V for 10 ms by the gun power supply establishing a high density plasma. Each plasma source is fired independently allowing for adjustable plasma parameters, with densities varying between 1018 -1019 m-3 and electron temperatures of 5-15 eV. Measurements were characterized using a 16 tip Langmuir probe. The plasma source will be used as a background plasma for the magnetized coaxial plasma gun (MCPG), the Terrestrial Reconnection Experiment (TREX), and as the plasma source for a magnetic mirror experiment. Temperature, density, and confinement results will be presented. This work is supported by the DoE and the NSF.

Electron gun jitter effects on beam bunching

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

Liu, M. S.; Iqbal, M., E-mail: muniqbal.chep@pu.edu.pk; Centre for High Energy Physics, University of the Punjab, Lahore 45590

For routine operation of Beijing Electron Positron Collider II (BEPCII) linac, many factors may affect the beam bunching process directly or indirectly. We present the measurements and analyses of the gun timing jitter, gun high voltage jitter, and beam energy at the exit of the standard acceleration section of the linac quantitatively. Almost 80 mV and more than 200 ps of gun high voltage and time jitters have ever been measured, respectively. It was analyzed that the gun timing jitter produced severe effects on beam energy than the gun high voltage jitter, if the timing jitter exceeded 100 ps whichmore » eventually deteriorates both the beam performance and the injection rate to the storage ring.« less

Characteristics and measurement of supersonic projectile shock waves by a 32-microphone ring array

NASA Astrophysics Data System (ADS)

Chang, Ho; Wu, Yan-Chyuan; Tsung, Tsing-Tshih

2011-08-01

This paper discusses about the characteristics of supersonic projectile shock wave in muzzle region during firing of high explosive anti-tank (HEAT) and high explosive (HE) projectiles. HEAT projectiles are fired horizontally at a muzzle velocity of Mach 3.5 from a medium caliber tank gun equipped with a newly designed multi-perforated muzzle brake, whereas HE projectiles are fired at elevation angles at a muzzle velocity of Mach 2 from a large caliber howitzer equipped with a newly designed double-baffle muzzle brake. In the near field, pressure signatures of the N-wave generated from projectiles are measured by 32-microphone ring array wrapped by cotton sheath. Records measured by the microphone array are used to demonstrate several key characteristics of the shock wave of supersonic projectile. All measurements made in this study can be a significant reference for developing guns, tanks, or the chassis of fighting vehicles.

Characteristics and measurement of supersonic projectile shock waves by a 32-microphone ring array.

PubMed

Chang, Ho; Wu, Yan-Chyuan; Tsung, Tsing-Tshih

2011-08-01

This paper discusses about the characteristics of supersonic projectile shock wave in muzzle region during firing of high explosive anti-tank (HEAT) and high explosive (HE) projectiles. HEAT projectiles are fired horizontally at a muzzle velocity of Mach 3.5 from a medium caliber tank gun equipped with a newly designed multi-perforated muzzle brake, whereas HE projectiles are fired at elevation angles at a muzzle velocity of Mach 2 from a large caliber howitzer equipped with a newly designed double-baffle muzzle brake. In the near field, pressure signatures of the N-wave generated from projectiles are measured by 32-microphone ring array wrapped by cotton sheath. Records measured by the microphone array are used to demonstrate several key characteristics of the shock wave of supersonic projectile. All measurements made in this study can be a significant reference for developing guns, tanks, or the chassis of fighting vehicles.

Broadband spectra of seismic survey air-gun emissions, with reference to dolphin auditory thresholds.

PubMed

Goold, J C; Fish, P J

1998-04-01

Acoustic emissions from a 2120 cubic in air-gun array were recorded through a towed hydrophone assembly during an oil industry 2-D seismic survey off the West Wales Coast of the British Isles. Recorded seismic pulses were sampled, calibrated, and analyzed post-survey to investigate power levels of the pulses in the band 200 Hz-22 kHz at 750-m, 1-km, 2.2-km, and 8-km range from source. At 750-m range from source, seismic pulse power at the 200-Hz end of the spectrum was 140 dB re: 1 microPa2/Hz, and at the 20-kHz end of the spectrum seismic pulse power was 90 dB re: 1 microPa2/Hz. Although the background noise levels of the seismic recordings were far in excess of ambient, due to the proximity of engine, propeller, and flow sources of the ship towing the hydrophone, seismic power dominated the entire recorded bandwidth of 200 Hz-22 kHz at ranges of up to 2 km from the air-gun source. Even at 8-km range seismic power was still clearly in excess of the high background noise levels up to 8 kHz. Acoustic observations of common dolphins during preceding seismic surveys suggest that these animals avoided the immediate vicinity of the air-gun array while firing was in progress, i.e., localized disturbance occurred during seismic surveying. Although a general pattern of localized disturbance is suggested, one specific observation revealed that common dolphins were able to tolerate the seismic pulses at 1-km range from the air-gun array. Given the high broadband seismic pulse power levels across the entire recorded bandwidth, and known auditory thresholds for several dolphin species, we consider such seismic emissions to be clearly audible to dolphins across a bandwidth of tens on kilohertz, and at least out to 8-km range.

The Green Canyon Event as Recorded by the Atlantis OBS Node Survey

NASA Astrophysics Data System (ADS)

Dellinger, J. A.; Ehlers, J.; Clarke, R.

2006-12-01

On 10 February, 2006, a magnitude 5.2 earthquake occurred 260~km South of New Orleans, Louisiana, in the Green Canyon area of the United States Gulf of Mexico. Fortuitously, at the time of the earthquake an array of nearly 500 ocean-bottom-seismic nodes happened to be recording about 40~km SouthEast of the epicenter. These nodes were part of an ongoing oil-exploration 3D-seismic survey ("Atlantis patch 2"), and were designed to record oil-exploration air-gun seismic signals (with a dominant frequency of about 15~Hz), not low-frequency earthquake signals (1~Hz). The survey's own air guns, located about 7~km to the SouthEast of the array at the time of the event, were also repeatedly firing, generating large amounts of "noise" (at least for the purposes of analyzing the earthquake signal). Not surprisingly, when the data are plotted at their original sample rate they are dominated by the Atlantis survey's air-gun signal. When low passed with an upper cutoff of 2~Hz, however, the air-gun signals essentially vanish and underlying natural signals are clearly revealed. In land-seismic exploration dense 3D arrays of single geophones are used to characterize unwanted surface-wave energy. Beam forming the dense array allows the directions and phase velocities of wavefronts propagating across the array to be identified and localized so that receiver arrays can be designed that best attenuate the surface-wave noise. The 400-meter spacing of the Atlantis node array was designed to be optimally sparse for reflection-seismic processing. At 1~Hz, however, a 400-meter spacing becomes "dense" and we were able to use the same toolkit of programs originally developed for analyzing surface waves in land-seismic data to analyze the earthquake waves. The analysis reveals a complex and protracted series of arrivals spanning nearly 20~minutes of time. The expected sequence of earthquake arrivals from the North-NorthWest are followed by weaker sequences of arrivals of unknown origin from first the SouthEast and then from the East. It is hoped that these data can be used to help constrain the location, depth, and mechanism of the Green Canyon event. The authors wish to thank BP and BHPB for their permission to present this work, Fairfield for their enthusiasm in preserving the data, and CGG, WesternGeco, and Fugro for their cooperation in identifying other sources of man-made signals in the data.

Experimental identification of the kink instability as a poloidal flux amplification mechanism for coaxial gun spheromak formation.

PubMed

Hsu, S C; Bellan, P M

2003-05-30

The magnetohydrodynamic kink instability is observed and identified experimentally as a poloidal flux amplification mechanism for coaxial gun spheromak formation. Plasmas in this experiment fall into three distinct regimes which depend on the peak gun current to magnetic flux ratio, with (I) low values resulting in a straight plasma column with helical magnetic field, (II) intermediate values leading to kinking of the column axis, and (III) high values leading immediately to a detached plasma. Onset of column kinking agrees quantitatively with the Kruskal-Shafranov limit, and the kink acts as a dynamo which converts toroidal to poloidal flux. Regime II clearly leads to both poloidal flux amplification and the development of a spheromak configuration.

Commissioning Results of the 2nd 3.5 Cell SRF Gun for ELBE

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

Arnold, A; Freitag, M; Murcek, Petr

As in 2007 the first 3.5 cell superconducting radio frequency (SRF) gun was taken into operation, it turned out that the specified performance has not been achieved. However, to demonstrate the full potential of this new type of electron source, a second and slightly modified SRF gun II was built in collaboration with Thomas Jefferson National Accelerator Facility (TJNAF). We will report on commissioning and first results of the new gun, which includes in particular the characterization of the most important RF properties as well as their comparison with previous vertical test results.

Measuring the Blast and Ballistic Performance of Armor

DTIC Science & Technology

2015-10-15

Typical ballistic test instrumentation is depicted in Fig. 1. The gun system employs a Mann barrel , available in a range of calibers1 (e.g., .22 cal...setup. (A) Mann barrel gun system; (B) computer and data acquisition interface; (C) remote, manual trigger; (D) velocity screens; (E) high speed video...1 Caliber corresponds to the diameter of the gun barrel , usually expressed in inches; e.g., .30 cal

Investigations and Applications of Field- and Photo-emitted Electron Beams from a Radio Frequency Gun

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

Panuganti, SriHarsha

Production of quality electron bunches using e cient ways of generation is a crucial aspect of accelerator technology. Radio frequency electron guns are widely used to generate and rapidly accelerate electron beams to relativistic energies. In the current work, we primarily study the charge generation processes of photoemission and eld emission inside an RF gun installed at Fermilab's High Brightness Electron Source Laboratory (HBESL). Speci cally, we study and characterize second-order nonlinear photoemission from a Cesium Telluride (Cs 2Te) semiconductor photocathode, and eld emission from carbon based cathodes including diamond eld emission array (DFEA) and carbon nanotube (CNT) cathodes locatedmore » in the RF gun's cavity. Finally, we discuss the application experiments conducted at the facility to produce soft x-rays via inverse Compton scattering (ICS), and to generate uniformly lled ellipsoidal bunches and temporally shaped electron beams from the Cs 2Te photocathode.« less

Management Perspectives Pertaining to Root Cause Analyses of Nunn-McCurdy Breaches. Volume 4

DTIC Science & Technology

2013-01-01

the FY2012 NDAA, the Army revised its initial budget request, allocating money from the purchase of new M2 .50 caliber machine guns to the...Quick-change machine gun barrel Explosive reactive armor Linear demolition charge system Full width, surface mine ploughs On-board vehicle power...Quantity Oversight of ACAT II Programs 45 for a restart to the program citing a “critical shortage of serviceable machine guns for our Soldiers who

Performance of a clinical gridded electron gun in magnetic fields: Implications for MRI-linac therapy.

PubMed

Whelan, Brendan; Holloway, Lois; Constantin, Dragos; Oborn, Brad; Bazalova-Carter, Magdalena; Fahrig, Rebecca; Keall, Paul

2016-11-01

MRI-linac therapy is a rapidly growing field, and requires that conventional linear accelerators are operated with the fringe field of MRI magnets. One of the most sensitive accelerator components is the electron gun, which serves as the source of the beam. The purpose of this work was to develop a validated finite element model (FEM) model of a clinical triode (or gridded) electron gun, based on accurate geometric and electrical measurements, and to characterize the performance of this gun in magnetic fields. The geometry of a Varian electron gun was measured using 3D laser scanning and digital calipers. The electric potentials and emission current of these guns were measured directly from six dose matched true beam linacs for the 6X, 10X, and 15X modes of operation. Based on these measurements, a finite element model (FEM) of the gun was developed using the commercial software opera/scala. The performance of the FEM model in magnetic fields was characterized using parallel fields ranging from 0 to 200 G in the in-line direction, and 0-35 G in the perpendicular direction. The FEM model matched the average measured emission current to within 5% across all three modes of operation. Different high voltage settings are used for the different modes; the 6X, 10X, and 15X modes have an average high voltage setting of 15, 10, and 11 kV. Due to these differences, different operating modes show different sensitivities in magnetic fields. For in line fields, the first current loss occurs at 40, 20, and 30 G for each mode. This is a much greater sensitivity than has previously been observed. For perpendicular fields, first beam loss occurred at 8, 5, and 5 G and total beam loss at 27, 22, and 20 G. A validated FEM model of a clinical triode electron gun has been developed based on accurate geometric and electrical measurements. Three different operating modes were simulated, with a maximum mean error of 5%. This gun shows greater sensitivity to in-line magnetic fields than previously presented models, and different operating modes show different sensitivity.

Performance of a clinical gridded electron gun in magnetic fields: Implications for MRI-linac therapy

PubMed Central

Whelan, Brendan; Holloway, Lois; Constantin, Dragos; Oborn, Brad; Bazalova-Carter, Magdalena; Fahrig, Rebecca; Keall, Paul

2016-01-01

Purpose: MRI-linac therapy is a rapidly growing field, and requires that conventional linear accelerators are operated with the fringe field of MRI magnets. One of the most sensitive accelerator components is the electron gun, which serves as the source of the beam. The purpose of this work was to develop a validated finite element model (FEM) model of a clinical triode (or gridded) electron gun, based on accurate geometric and electrical measurements, and to characterize the performance of this gun in magnetic fields. Methods: The geometry of a Varian electron gun was measured using 3D laser scanning and digital calipers. The electric potentials and emission current of these guns were measured directly from six dose matched true beam linacs for the 6X, 10X, and 15X modes of operation. Based on these measurements, a finite element model (FEM) of the gun was developed using the commercial software opera/scala. The performance of the FEM model in magnetic fields was characterized using parallel fields ranging from 0 to 200 G in the in-line direction, and 0–35 G in the perpendicular direction. Results: The FEM model matched the average measured emission current to within 5% across all three modes of operation. Different high voltage settings are used for the different modes; the 6X, 10X, and 15X modes have an average high voltage setting of 15, 10, and 11 kV. Due to these differences, different operating modes show different sensitivities in magnetic fields. For in line fields, the first current loss occurs at 40, 20, and 30 G for each mode. This is a much greater sensitivity than has previously been observed. For perpendicular fields, first beam loss occurred at 8, 5, and 5 G and total beam loss at 27, 22, and 20 G. Conclusions: A validated FEM model of a clinical triode electron gun has been developed based on accurate geometric and electrical measurements. Three different operating modes were simulated, with a maximum mean error of 5%. This gun shows greater sensitivity to in-line magnetic fields than previously presented models, and different operating modes show different sensitivity. PMID:27806583

Forum: The Future of Instructional Communication. Guns on Campus: Creating Research to Inform Practice

ERIC Educational Resources Information Center

Horan, Sean M.; Bryant, Leah E.

2017-01-01

This essay encourages research on the presence of guns in college classrooms. Readers are asked to consider that around 11 million individuals have concealed carry permits (Crime Prevention Research Center, 2014), and roughly 20% of states allow concealed guns on campus (e.g., Anderson, 2016). Given the centrality of guns in our culture, and…

Characterizing the plasma of the Rotating Wall Machine

NASA Astrophysics Data System (ADS)

Hannum, David A.

The Rotating Wall Machine (RoWM) is a line-tied linear screw pinch built to study current-driven external kink modes. The plasma column is formed by an array of seven electrostatic washer guns which can also be biased to drive plasma current. The array allows independent control over the electron density ne and current density Jz profiles of the column. Internal measurements of the plasma have been made with singletip Langmuir and magnetic induction ("B-dot") probes for a range of bias currents (Ib = 0, 300, 500 A/gun). Streams from the individual guns are seen to merge at a distance of z ≈ 36 cm from the guns; the exact distance depends on the value of Ib. The density of the column is directly proportional to the Ohmic dissipation power, but the temperature stays at a low, uniform value (Te ≈ 3.5 eV) for each bias level. Electron densities are on the order of ne ˜10 20 m-3. The electron density expands radially (across the Bz guide field) as the plasma moves along the column, though the current density Jz mainly stays parallel to the field lines. The singletip Langmuir probe diagnostic is difficult to analyze for Ib = 500 A/gun plasmas and fails as Ib is raised beyond this level. Spectrographic analysis of the Halpha line indicates that the hydrogen plasmas are nearly fully ionized at each bias level. Azimuthal E x B rotation is axially and radially sheared; rotation slows as the plasma reaches the anode. Perpendicular diffusivity is consistent with the classical value, D⊥ ≈ 5 m2/sec, while parallel resistivity is seen to be twice the classical Spitzer value, 2 x 10-4 O m.

Development program on a cold cathode electron gun

NASA Technical Reports Server (NTRS)

Spindt, C. A.; Holland, C. E.

1985-01-01

During this phase of the cathode development program, SRI improved the multiple electron beam exposure system used to print hole patterns for the cathode arrays, studied anisotropic etch processes, conducted cathode investigations using an emission microscope, reviewed possible alternate materials for cathode fabrication, studied cathode storage techniques, conducted high power operation experiments, and demonstrated high-current-density operation with small arrays of tips.

Jumping the gun: firearms and the mental health of Australians.

PubMed

Dudley, M; Cantor, C; de Moore, G

1996-06-01

The aims of this study were to (i) survey mental health-related correlates of firearms ownership and availability in Australia, and (ii) assess possible causal relationships between civilian gun deaths, gun availability and mental disorders. Available data regarding firearms ownership, injuries and deaths were reviewed as well as studies of (i) gun ownership, suicide and homicide, and (ii) gun control laws and suicide. Findings indicated that 85% of firearm deaths are triggered by distress, as opposed to crime. Most firearm homicides are intrafamilial or involve familiar persons. Firearm suicide rates, although tapering off in recent years, continue to rise among certain groups. It was also found that: (1) Beyond reasonable doubt, a causal relationship exists between gun ownership and firearm suicides and homicides. The role of method substitution is controversial, but is probably less important among the young. (2) Outside the United States, legislation may be useful in reducing firearm and possibly overall suicide rates. (3) If firearm owners are representative of the community, then 15-20% suffer from a psychiatric disorder at any time. While a modest increase in risk of firearms misuse exists for this group, especially those with a history of substance abuse or violence, concern also arises regarding those with mental disorders who access firearms because owners have not secured them. No uniform definition or way of verifying self-reports exists for gun licence applicants regarding these issues. Further regulation of firearm safety and availability is warranted. Public health measures include improved surveillance regarding firearm events, advocacy for appropriate firearm legislation, and better education and communication about firearms.

49 CFR 173.62 - Specific packaging requirements for explosives.

Code of Federal Regulations, 2014 CFR

2014-10-01

... material. No more than two segregated initiation devices per gun may be carried on the same motor vehicle... other or any other article or material carried in the vehicle; and (ii) The assembled gun packed on the... HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS...

Napoleon’s Cavalry: A Key Element to Decisive Victory

DTIC Science & Technology

2002-05-31

known for their “ panache , daring, and gallantry.”26 Napoleon’s cavalry enjoyed their effectiveness on the battlefield until 1813 when two important...thus rendering the Prussians helpless and in no position to bargain with the victor . Napoleon’s military victory, largely due to his pursuit, had...1813. Imperial Guard 30,000 Inf 8000 Cav 202 Guns II Corps Victor 17,241 Inf 55 Guns III Corps Souham 13,034 Inf 1065 Cav 61 Guns IV Corps Bertrand

Formation of Imploding Plasma Liners for HEDP and MIF Application

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

Witherspoon, F. Douglas; Case, Andrew; Brockington, Samuel

Plasma jets with high density and velocity have a number of important applications in fusion energy and elsewhere, including plasma refueling, disruption mitigation in tokamaks, magnetized target fusion, injection of momentum into centrifugally confined mirrors, plasma thrusters, and high energy density plasmas (HEDP). In Magneto-Inertial Fusion (MIF), for example, an imploding material liner is used to compress a magnetized plasma to fusion conditions and to confine the resulting burning plasma inertially to obtain the necessary energy gain. The imploding shell may be solid, liquid, gaseous, or a combination of these states. The presence of the magnetic field in the targetmore » plasma suppresses thermal transport to the plasma shell, thus lowering the imploding power needed to compress the target to fusion conditions. This allows the required imploding momentum flux to be generated electromagnetically using off-the-shelf pulsed power technology. Practical schemes for standoff delivery of the imploding momentum flux are required and are open topics for research. One approach for accomplishing this, called plasma jet driven magneto-inertial fusion (PJMIF), uses a spherical array of pulsed plasma guns to create a spherically imploding shell of very high velocity, high momentum flux plasma. This approach requires development of plasma jet accelerators capable of achieving velocities of 50-200 km/s with very precise timing and density profiles, and with high total mass and density. Low-Z plasma jets would require the higher velocities, whereas very dense high-Z plasma shells could achieve the goal at velocities of only 50-100 km/s. In this report, we describe our work to develop the pulsed plasma gun technology needed for an experimental scientific exploration of the PJMIF concept, and also for the other applications mentioned earlier. The initial goal of a few hundred of hydrogen at 200 km/s was eventually replaced with accelerating 8000 μg of argon or xenon to 50 km/s for the Plasma Liner Experiment (PLX) at Los Alamos National Laboratory (LANL). Initial work used existing computational and analytical tools to develop and refine a specific plasma gun concept having a novel tapered coaxial electromagnetic accelerator contour with an array of symmetric ablative plasma injectors. The profile is designed to suppress the main barrier to success in coaxial guns, namely the blow-by instability in which the arc slips past and outruns the bulk of the plasma mass. Efforts to begin developing a set of annular non-ablative plasma injectors for the coaxial gun, in order to accelerate pure gases, resulted in development of linear parallel-plate MiniRailguns that turned out to work well as plasma guns in their own right and we subsequently chose them for an initial plasma liner experiment on the PLX facility at LANL. This choice was mainly driven by cost and schedule for that particular experiment, while longer term goals still projected use of coaxial guns for reactor-relevant applications for reasons of better symmetry, lower impurities, more compact plasma jet formation, and higher gun efficiency. Our efforts have focused mainly on 1) developing various plasma injection systems for both coax and linear railguns and ensuring they work reliably with the accelerator section, 2) developing a suite of plasma and gun diagnostics, 3) performing computational modeling to design and refine the plasma guns, 4) establishing a research facility dedicated to plasma gun development, and finally, 5) developing plasma guns and associated pulse power systems capable of achieving these goals and installing and testing the first two gun sets on the PLX facility at LANL. During the second funding cycle for this program, HyperV joined in a collaborative effort with LANL, the University of Alabama at Huntsville, and the University of New Mexico to perform a plasma liner experiment (PLX) to investigate the physics and technology of forming spherically imploding plasma liners. HyperV’s tasks focused on developing the plasma guns and associated pulse power systems required for the 30 gun experiment at LANL. Unfortunately, funding for the entire PLX collaborative project was terminated after only two years of the four year project due to program funding realignments which necessitated recompeting the project in midstream. Despite the loss of funding, HyperV installed two Mark1 guns and pulsed power systems on PLX, and jet characterization and merging experiments were subsequently successfully performed at LANL by the PLX Team. In parallel with those PLX experiments, HyperV continued its efforts to develop a plasma gun capable of meeting the PLX goal of 8 mg of argon at 50 km/s. HyperV was ultimately successful in this effort, demonstrating 10.8 mg at 52.8 km/s and 7.5 mg at 62.4 km/s with the Mark2 MiniRailgun.« less

Charge Design Considerations and Their Effect on Pressure Waves in Guns

DTIC Science & Technology

1980-12-01

Interior Ballistic Analysis of Guns", "Interior Ballistics of Guns Ed, M. Summerfield and H. Krier, Progress in Astro - nautics and Aeronautics, Vol. 66...8217 • - -O.8 - Fx " • 0.48 S0.2 U G 00 2 4 64_ . -APi (kpsi) Figure 28. Distribution of Pressure-Wave Amplitudes f r the 175-mm, M107 Gun (M86A2, Zone 3

The HyperV Full-Scale Contoured-Gap Coaxial Plasma Railgun

NASA Astrophysics Data System (ADS)

Brockington, Samuel; Case, Andrew; Messer, Sarah; Bomgardner, Richard; Elton, Raymond; Wu, Linchun; Witherspoon, F. Douglas

2009-11-01

HyperV has been developing pulsed plasma injected coaxial railguns with a contoured gap profile designed to mitigate the blowby instability. Previous work using half-scale guns has been successful in launching 150 μg plasmas at 90 km/s [1]. In order to meet the original goal of 200 μg at 200 km/s the full-scale coaxial plasma gun has been constructed, and initial testing is beginning. This new plasma gun consists of two machined aluminum electrodes and a UHMW polyethylene breech insulator. The gun is breech fed by 64 ablative polyethylene capillary discharge units identical to the half-scale gun units. Maximum accelerator energy storage has also been increased 50%. Refractory coatings may be necessary to allow full current (˜800 kA) operation. The outer electrode includes 24 small diagnostic ports for optical and magnetic probe access to the plasma inside the gun to allow direct measurement of the plasma armature dynamics. Initial test data from the full-scale coax gun will be presented along with plans for future testing. Work supported by the U.S. DOE Office of Fusion Energy Sciences.[4pt] [1] F. D. Witherspoon, A. Case, S. Messer, R. Bomgardner, M. Phillips, S. Brockington, R. Elton, ``Contoured Gap Coaxial Plasma Gun with Injected Plasma Armature'' Rev. Sci. Instr. submitted (2009)

Advanced photoinjector experiment photogun commissioning results

NASA Astrophysics Data System (ADS)

Sannibale, F.; Filippetto, D.; Papadopoulos, C. F.; Staples, J.; Wells, R.; Bailey, B.; Baptiste, K.; Corlett, J.; Cork, C.; De Santis, S.; Dimaggio, S.; Doolittle, L.; Doyle, J.; Feng, J.; Garcia Quintas, D.; Huang, G.; Huang, H.; Kramasz, T.; Kwiatkowski, S.; Lellinger, R.; Moroz, V.; Norum, W. E.; Padmore, H.; Pappas, C.; Portmann, G.; Vecchione, T.; Vinco, M.; Zolotorev, M.; Zucca, F.

2012-10-01

The Advanced Photoinjector Experiment (APEX) at the Lawrence Berkeley National Laboratory is dedicated to the development of a high-brightness high-repetition rate (MHz-class) electron injector for x-ray free-electron laser (FEL) and other applications where high repetition rates and high brightness are simultaneously required. The injector is based on a new concept rf gun utilizing a normal-conducting (NC) cavity resonating in the VHF band at 186 MHz, and operating in continuous wave (cw) mode in conjunction with high quantum efficiency photocathodes capable of delivering the required charge at MHz repetition rates with available laser technology. The APEX activities are staged in three phases. In phase 0, the NC cw gun is built and tested to demonstrate the major milestones to validate the gun design and performance. Also, starting in phase 0 and continuing in phase I, different photocathodes are tested at the gun energy and at full repetition rate for validating candidate materials to operate in a high-repetition rate FEL. In phase II, a room-temperature pulsed linac is added for accelerating the beam at several tens of MeV to reduce space charge effects and allow the measurement of the brightness of the beam from the gun when integrated in an injector scheme. The installation of the phase 0 beam line and the commissioning of the VHF gun are completed, phase I components are under fabrication, and initial design and specification of components and layout for phase II are under way. This paper presents the phase 0 commissioning results with emphasis on the experimental milestones that have successfully demonstrated the APEX gun capability of operating at the required performance.

Spindt cold cathode electron gun development program

NASA Technical Reports Server (NTRS)

Spindt, C. A.

1983-01-01

A thin film field emission cathode array and an electron gun based on this emitter array are summarized. Fabricating state of the art cathodes for testing at NASA and NRL, advancing the fabrication technology, developing wedge shaped emitters, and performing emission tests are covered. An anistropic dry etching process (reactive ion beam etching) developed that leads to increasing the packing density of the emitter tips to about 5 x 10 to the 6th power/square cm. Tests with small arrays of emitter tips having about 10 tips has demonstrated current densities of over 100 A/sq cm. Several times using cathodes having a packing density of 1.25 x 10 to the 6th power tips/sq cm. Indications are that the higher packing density achievable with the dry etch process may extend this capability to the 500 A/sq cm range and beyond. The wedge emitter geometry was developed and shown to produce emission. This geometry can (in principle) extend the current density capability of the cathodes beyond the 500 A/sq cm level. An emission microscope was built and tested for use with the cathodes.

Proceedings of the US Army Symposium on Gun Dynamics (2nd), Held at the Institute on Man and Science, Rensselaerville, N.Y. 19-22 September 1978

DTIC Science & Technology

1978-09-01

Alamo Avenue, S.E. Albuquerque, New Mexico 87106 ABSTRACT: A system for measuring the angular motion of the muzzle of artil- lery weapons during firing...0051, while the author was at EG&G, Inc., Albuquerque Operations, Albuquerque, New Mexico . 01 1-33 COX AND HOKANSON TITLE: Muzzle Motions of the M68...1978. DEGREES HELD: B.A. Chemical Engineer, New Mexico State University, University Park, New Mexico . 1 II1-34 COUNTER RECOIL SYSTEM EFFECTS ON

Initial Beam Dynamics Simulations of a High-Average-Current Field-Emission Electron Source in a Superconducting RadioFrequency Gun

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

Mohsen, O.; Gonin, I.; Kephart, R.

High-power electron beams are sought-after tools in support to a wide array of societal applications. This paper investigates the production of high-power electron beams by combining a high-current field-emission electron source to a superconducting radio-frequency (SRF) cavity. We especially carry out beam-dynamics simulations that demonstrate the viability of the scheme to formmore » $$\\sim$$ 300 kW average-power electron beam using a 1+1/2-cell SRF gun.« less

Investigation of a staged plasma-focus apparatus. [pinch construction and current sheet dynamics investigation

NASA Technical Reports Server (NTRS)

Lee, J. H.; Mcfarland, D. R.; Harries, W. L.

1978-01-01

A new staged plasma-focus geometry combining two Mather-type plasma-focus guns was constructed, and the current-sheet dynamics were investigated. The production of simultaneous pairs of plasma foci was achieved. The intensities of X-ray and fusion-neutron emission were measured and found to agree with the scaling law for a plasma focus. Advantages of this new geometry include the possibility of using plasma-focus type pinches in multiple arrays at power levels beyond the validity regime of the current scaling law for a single gun.

Accidental Bolt Gun Injury to Femur - A Case Report.

PubMed

Kattimani, Ravi Prasad; Shetty, Sanath; Mirza, Humayun

2016-01-01

Bolt gun or slaughterer's guns are used in meat industry for "humane killing" of animals. Injuries caused by bolt gun are rare, reported exclusively from central European countries. We report a case of 28 year old male, who accidentally shot himself with a bolt gun to his right thigh. A 28 years old male presented to our Accident and Emergency department after accidental injury to his right thigh with bolt gun. He had an entry wound measuring 2 cm in length and 1 cm in breadth over anterior aspect of lower one third of thigh at lower and sustained Grade II compound fracture of right femur shaft at distal one third. The wound was treated with multiple debridements, negative pressure wound therapy and intravenous antibiotics based on culture and sensitivity. Bolt gun or slaughterer's guns are weapons used in meat industry for slaughtering animals. Wounds inflicted by bolt guns have specific morphological feature, distinctive from wounds made by other kinds of hand firearms. Most of the time wound will be infected at presentation. Lesions caused by these weapons are likely to have a more serious character than is to be expected from the size of the entrance wound. The mainstay of treatment is liberal wound exploration, multiple debridement's and intra venous antibiotics based on culture reports to treat infection and prevent morbidity.

Tailored ramp wave generation in gas gun experiments

NASA Astrophysics Data System (ADS)

Cotton, Matthew; Chapman, David; Winter, Ron; Harris, Ernie; Eakins, Daniel

2015-09-01

Gas guns are traditionally used as platforms to introduce a planar shock wave to a material using plate impact methods, generating states on the Hugoniot. The ability to deliver a ramp wave to a target during a gas gun experiment enables access to different regions of the equation-of-state surface, making it a valuable technique for characterising material behaviour. Previous techniques have relied on the use of multi-material impactors to generate a density gradient, which can be complex to manufacture. In this paper we describe the use of an additively manufactured steel component consisting of an array of tapered spikes which can deliver a ramp wave over ˜ 2 μs. The ability to tailor the input wave by varying the component design is discussed, an approach which makes use of the design freedom offered by additive manufacturing techniques to rapidly iterate the spike profile. Results from gas gun experiments are presented to evaluate the technique, and compared with 3D hydrodynamic simulations.

Seek, Strike, and Destroy: U.S. Army Tank Destroyer Doctrine in World War II (Leavenworth Papers, Number 12)

DTIC Science & Technology

1985-09-01

velocity 75-mm gun that fired a tungsten carbide antitank round, and the massive Mark VI Tiger tank , which carried a version. of the deadly 88-mm gun...guns would be able to penetrate the frontal armor of the massive Mark VI Tiger tank at a comfortable two thousand yards.27 Prior to the invasion, the...conceived counterattack aimed at recapturing the Sidi-bou-Zid position and. was badly battered in the ensuing German ambush,17 . A damaged Mark VI Tiger

Gun violence trends in movies.

PubMed

Bushman, Brad J; Jamieson, Patrick E; Weitz, Ilana; Romer, Daniel

2013-12-01

Many scientific studies have shown that the mere presence of guns can increase aggression, an effect dubbed the "weapons effect." The current research examines a potential source of the weapons effect: guns depicted in top-selling films. Trained coders identified the presence of violence in each 5-minute film segment for one-half of the top 30 films since 1950 and the presence of guns in violent segments since 1985, the first full year the PG-13 rating (age 13+) was used. PG-13-rated films are among the top-selling films and are especially attractive to youth. Results found that violence in films has more than doubled since 1950, and gun violence in PG-13-rated films has more than tripled since 1985. When the PG-13 rating was introduced, these films contained about as much gun violence as G (general audiences) and PG (parental guidance suggested for young children) films. Since 2009, PG-13-rated films have contained as much or more violence as R-rated films (age 17+) films. Even if youth do not use guns, these findings suggest that they are exposed to increasing gun violence in top-selling films. By including guns in violent scenes, film producers may be strengthening the weapons effect and providing youth with scripts for using guns. These findings are concerning because many scientific studies have shown that violent films can increase aggression. Violent films are also now easily accessible to youth (e.g., on the Internet and cable). This research suggests that the presence of weapons in films might amplify the effects of violent films on aggression.

NPS Gas Gun for Planar Impact Studies

NASA Astrophysics Data System (ADS)

Cheong Ho, Chien; Hixson, Robert

2009-11-01

The Naval Postgraduate School (NPS) commissioned a Gas Gun for shock wave studies on 9^th October 2009, by performing the first experiment. The Gas Gun is the key element of NPS Shock Wave Research Program within the Physics Department, where well-characterized planar impacts are essential for obtaining high quality data, to characterize a solid material. This first experiment was very successful, and returned key data on the quality of the impact conditions created. The Gas Gun is designed by SANDIA NATIONAL LABORATORIES, and the NPS spent twelve months fabricating the components of the Gas Gun and six months assembling the Gas Gun. Three inch projectile are launched at velocities up to 0.5 km/s, creating high pressure and temperature states that can be used to characterize the fundamental response of relevant materials to dynamic loading. The projectile is launched from a `wrap around' gas breech where helium gas is pressurized to relatively low pressure. This gas is used to accelerate the projectile down a 3m barrel. Upon impact, the speed of the projectile and the flatness of the impact is measured, via a stepped circular pin array circuit. The next stage of development for the Gas Gun is to integrate a Velocity Interferometer System for Any Reflector (VISAR). The VISAR sees all the waves that flow through the target plate as a result of the impact. This is a key diagnostic for determining material properties under dynamic loading conditions.

Association Between Substance Use and Gun-Related Behaviors

PubMed Central

Chen, Danhong; Wu, Li-Tzy

2016-01-01

Gun-related violence is a public health concern. This study synthesizes findings on associations between substance use and gun-related behaviors. Searches through PubMed, Embase, and PsycINFO located 66 studies published in English between 1992 and 2014. Most studies found a significant bivariate association between substance use and increased odds of gun-related behaviors. However, their association after adjustment was mixed, which could be attributed to a number of factors such as variations in definitions of substance use and gun activity, study design, sample demographics, and the specific covariates considered. Fewer studies identified a significant association between substance use and gun access/possession than other gun activities. The significant association between nonsubstance covariates (e.g., demographic covariates and other behavioral risk factors) and gun-related behaviors might have moderated the association between substance use and gun activities. Particularly, the strength of association between substance use and gun activities tended to reduce appreciably or to become nonsignificant after adjustment for mental disorders. Some studies indicated a positive association between the frequency of substance use and the odds of engaging in gun-related behaviors. Overall, the results suggest a need to consider substance use in research and prevention programs for gun-related violence. PMID:26769722

Many Point Optical Velocimetry for Gas Gun Applications

NASA Astrophysics Data System (ADS)

Pena, Michael; Becker, Steven; Garza, Anselmo; Hanache, Michael; Hixson, Robert; Jennings, Richard; Matthes, Melissa; O'Toole, Brendan; Roy, Shawoon; Trabia, Mohamed

2015-06-01

With the emergence of the multiplexed photonic Doppler velocimeter (MPDV), it is now practical to record many velocity traces simultaneously on shock physics experiments. Optical measurements of plastic deformation during high velocity impact have historically been constrained to a few measurement points. We have applied a 32-channel MPDV system to gas gun experiments in order to measure plastic deformation of a steel plate. A two dimensional array of measurement points allowed for diagnostic coverage over a large surface area of the target plate. This provided experimental flexibility to accommodate platform uncertainties as well as provide for a wealth of data from a given experiment. The two dimensional array of measurement points was imaged from an MT fiber-optic connector using off-the-shelf optical components to allow for an economical and easy-to-assemble, many-fiber probe. A two-stage, light gas gun was used to launch a Lexan projectile at velocities ranging from 4 to 6 km/s at a 12.7 mm thick A36 steel plate. Plastic deformation of the back surface was measured and compared with simulations from two different models: LS-DYNA and CTH. Comparison of results indicates that the computational analysis using both codes can reasonably simulate experiments of this type.

Seismic reflection and refraction data acquired in Canada Basin, Northwind Ridge and Northwind Basin, Arctic Ocean in 1988, 1992 and 1993

USGS Publications Warehouse

Grantz, Arthur; Hart, Patrick E.; May, Steven D.

2004-01-01

Seismic reflection and refraction data were collected in generally ice-covered waters of the Canada Basin and the eastern part of the Chukchi Continental Borderland of the Amerasia Basin, Arctic Ocean, during the late summers of 1988, 1992, and 1993. The data were acquired from a Polar class icebreaker, the U.S. Coast Guard Cutter Polar Star, using a seismic reflection system designed by the U.S. Geological Survey (USGS). The northernmost data extend to 78? 48' N latitude. In 1988, 155 km of reflection data were acquired with a prototype system consisting of a single 195 cubic inch air gun seismic source and a two-channel hydrophone streamer with a 150-m active section. In 1992 and 1993, 500 and 1,900 km, respectively, of seismic reflection profile data were acquired with an improved six air gun, 674 to 1303 cubic inch tuned seismic source array and the same two-channel streamer. In 1993, a 12-channel streamer with a 150-m active section was used to record five of the reflection lines and one line was acquired using a three air gun, 3,000 cubic inch source. All data were recorded with a DFS-V digital seismic recorder. Processed sections feature high quality vertical incidence images to more than 6 km of sub-bottom penetration in the Canada Basin. Refraction data were acquired with U.S. Navy sonobuoys recorded simultaneously with the seismic reflection profiles. In 1988 eight refraction profiles were recorded with the single air gun, and in 1992 and 1993 a total of 47 refraction profiles were recorded with the six air gun array. The sonobuoy refraction records, with offsets up to 35 km, provide acoustic velocity information to complement the short-offset reflection data. The report includes trackline maps showing the location of the data, as well as both digital data files (SEG-Y) and images of all of the profiles.

ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT: HVLP COATING EQUIPMENT, ITW AUTOMOTIVE REFINISHING, DEVILBISS GTI-600G, HVLP SPRAY GUN

EPA Science Inventory

This report presents the results of the verification test of the DeVilbiss GTi-600G high-volume, low-pressure gravity-feed spray gun, hereafter referred to as the DeVilbiss GTi, which is designed for use in automotive refinishing. The test coating chosen by ITW Automotive Refinis...

TU-H-BRA-03: Performance of a Clinical Gridded Electron Gun in Magnetic Fields: Implications for MRI-Linac Therapy

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

Whelan, B; Keall, P; Bazalova-Carter, M

Purpose: Recent advances towards MRI Linac radiotherapy have motivated a wide range of studies characterizing electromagnetic interactions between the two devices. One of the most sensitive components is the linac electron gun. To data, only non gridded (diode) guns have been investigated however, most linac vendors utilize gridded (triode) guns, which enable efficient and robust beam gating. The purpose of this study was to develop a realistic model of a gridded gun used clinically, and to characterize its performance in magnetic fields. Methods: The gridded electron gun used on Varian high energy machines was measured using 3D laser scanning quotedmore » as accurate to 0.1mm. Based on the scane, a detailed CAD mode was developed. From this, key geometry was extracted and a FEM model was developed (Opera/SCALA). Next, the high voltage (HV), grid voltage, and emission current were read from six dose matched TrueBeam linacs for the 6X, 10X and 15X photon modes (0 B-field). The mean values were used to represent each mode, which was simulated I constant magnetic fields from 0–200G in-line, and 0–35G perpendicular. Results: Experimentally measured HV, grid voltage, and emission current from 6X, 10X and 15X modes were respectively: 15±.03kV, 10±.08kV, 11±.03kV; 93±7V, 41±3V, and 70±6V; 327±27mA, 129±10mA, and 214±19mA. The error in simulated emission current of each mode was 3%,6%, and 3%. For in-line fields, 50% beam loss occurred at 114, 96, and 97G; for perpendicular; at 12, 13 and 14G. Sensitivity for a given geometry is primarily determined by HV setting. Conclusion: Future MRI-Linac systems will almost certainly use gridded guns. We present the first model of a clinical gridded gun, and match the experimental emission current to within 6% across three different operating modes. This clinical gun shows increased sensitivity to magnetic fields than previous work,and different modes show different sensitivity.« less

Ferromagnetic resonance response of electron-beam patterned arrays of ferromagnetic nanoparticles

NASA Astrophysics Data System (ADS)

Jung, Sukkoo; Watkins, Byron; Feller, Jeffrey; Ketterson, John; Chandrasekhar, Venkat

2001-03-01

We report on the fabrication and the dynamic magnetic properties of periodic permalloy dot arrays. Electron-beam lithography and e-gun evaporation have been used to make the arrays with the aspect ratio of 2 (dot diameter : 40 nm, height : 80 nm) and periods of 100 - 200 nm. The magnetic properties of the arrays and their interactions have been investigated by ferromagnetic resonance (FMR), magnetic force microscopy (MFM), and SQUID magnetometry. The measured FMR data show that the position and magnitude of resonant absorption peaks strongly depend on the angle between magnetic field and the lattice structure. The results of dot arrays with various kinds of structural parameters will be presented. Supported by Army Research Office, DAAD19-99-1-0334/P001

The Coast Artillery Journal. Volume 78, Number 5, September-October 1935

DTIC Science & Technology

1935-10-01

Scoring 345 By C’aptain Homer Case . The Tank Ju-Ju 349 BJ’ (’aptain .Tames A . McGuire. Some Facts About Bombardme󈧏t Aviation By Major Claire L. Chennault...north, endina the fifth yearlyJ ~. camp at Fort T a ~,lor. By MAJOR P. L. WALL, CA., N.G. classified." The guns used Case III firing for the first time...Frontispiece 322 Who Started Such a Mess? 330 By Lieut€>nantE. F. Adams Press Ce�Orshipin Wax Time- Part II 358 By Major Harry W. Caygill

The Scaling of Bird Impact Loads

DTIC Science & Technology

1979-06-01

large air storage tank used for driving the gun. The driving air storage tank had a capacity of approximately 0.85 M 3 . There was a valve system...located between the driving air storage tank and the breech of tile gun. This valve system was designed to valve the high pressure air from the driving...821710.0000 %111 _x4 I4 (11Xt*11141 .14.0000 YIVNI~II 1 *uIi0000 MIAtV iIIflY*iA) 󈧕 .000 XS𔃾 ’,41(IINV*t141 ’I t1. 0000 YIl’m 214 ’tI#4’ tf1 : K.- ’’I.00001

KSC-97PC1126

NASA Image and Video Library

1997-07-24

Applied Physics Laboratory engineers and technicians from Johns Hopkins University test solar array deployment of the Advanced Composition Explorer (ACE) in KSC’s Spacecraft Assembly and Encapsulation Facility-II (SAEF-II). The wire hanging from the ceiling above the black solar array panel is used for "g-negation," which takes the weight off of the panel’s hinges to simulate zero gravity, mimicking deployment in space. Scheduled for launch on a Delta II rocket from Cape Canaveral Air Station on Aug. 25, ACE will study low-energy particles of solar origin and high-energy galactic particles. The collecting power of instruments aboard ACE is 10 to 1,000 times greater than anything previously flown to collect similar data by NASA

Magnetron Electron Gun,

DTIC Science & Technology

1980-05-23

ULMAGNETRON ELECTRON GUN . (U) .Ay G0 A L GOLOENBERG, T B PANKRATOVA UNCLASSIFIED FTD..In(RS)T41896-?9 4 __ ihD - -111113 MICROCOPY RESOLUTION TEST...CHART NATIONAL BUREAU OF STANDARD 1961 A -_"D-I-D ,RS)T-18q6-79 v FOREIGN TECHNOLOGY DIVISION MAGNETRON ELECTRON GUN by A. L. Gol’denberg, T. B...VISION. WP.AP6. OHIO. FTD -ID(RS)T-1396-79 Date z.-.:a’,-lq -,o • 110ewm /A Is a, -D r.l MAGNETRON ELECTRON GUN A. L. Gol’denberg, T. B. Pankratova and M

Using Probabilistic Terrorism Risk Modeling for Regulatory Benefit-Cost Analysis. Application to the Western Hemisphere Travel Initiative Implemented in the Land Environment

DTIC Science & Technology

2007-05-01

Dixon and Stern, 2004), and gun violence prevention programs ( Tita et al., 2003). As DHS considers promulgating regulations and implementing new...communication 2/21/07. Tita , G., K. J. Riley, G. Ridgeway, C. A. Grammich, A. Abrahamse, and P. W. Greenwood (2003), Reducing Gun Violence: Results

Reusable Rapid Prototyped Blunt Impact Simulator

DTIC Science & Technology

2016-08-01

for a nonclassical gun experimental application. 15. SUBJECT TERMS rapid prototype, additive manufacturing, reusable projectile, 3-axis accelerometer... gun -launched applications.1,2 SLS technology uses a bed of powdered material that is introduced to a laser. The laser is controlled by a computer to...in creating internal gun -hardened electronics for a variety of high-g applications, GTB developed an internal electronics package containing a COTS

5. GUN MOUNT ON TERRACE, EAST VIEW (1992). WrightPatterson ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. GUN MOUNT ON TERRACE, EAST VIEW (1992). - Wright-Patterson Air Force Base, Area B, Building 71, Power Plant Engine Test Torque Stands, Seventh Street between D & G Streets, Dayton, Montgomery County, OH

20000G shock energy harvesters for gun-fired munition

NASA Astrophysics Data System (ADS)

Willemin, J.; Boisseau, S.; Olmos, L.; Gallardo, M.; Despesse, G.; Robert, T.

2016-11-01

This paper presents a 20000G shock energy harvester dedicated to gun-fired munitions and based on a mass-spring resonant structure coupled to a coil-magnet electromagnetic converter. The 20000G shock energy is firstly stored in the spring as elastic potential energy, released as mass-spring mechanical oscillations right after the shock and finally converted into electricity thanks to the coil-magnet transducer. The device has been modeled, sized to generate 200mJ in 150ms, manufactured and tested in a gun-fired munition. The prototype sizes 117cm3 and weighs 370g. 210mJ have been generated in a test bench and 140mJ in real conditions; this corresponds to a mean output power of 0.93W (7.9mW/cm3) and a maximum output power of 4.83W (41.3mW/cm3) right after the shock.

The hot plasma environment and floating potentials of an electron-beam-emitting rocket in the ionosphere

NASA Technical Reports Server (NTRS)

Arnoldy, R. L.; Winckler, J. R.

1981-01-01

The plasma environment surrounding the Echo III accelerator payload is examined with an extensive array of particle sensors. Suprathermal electrons are produced isotropically around the payload during the gun firings and decay away in approximately 32 ms. The largest directional intensities of this component are observed at the higher altitudes. Quick echo electrons are also observed to produce suprathermal electrons when they encounter the payload. The hot electrons surrounding the accelerator payload during gun injections bring sufficient charge to the payload to neutralize it provided the loss of charge by secondary production on the payload skin is small. Since the hot population exists for tens of milliseconds after the gun turnoff, it results in driving the payload up to 4 volts negative during this time. Quick echo electrons creating suprathermal electrons around the payload also drive the payload to a few volts negative.

Association Between Substance Use and Gun-Related Behaviors.

PubMed

Chen, Danhong; Wu, Li-Tzy

2016-01-01

Gun-related violence is a public health concern. This study synthesizes findings on associations between substance use and gun-related behaviors. Searches through PubMed, Embase, and PsycINFO located 66 studies published in English between 1992 and 2014. Most studies found a significant bivariate association between substance use and increased odds of gun-related behaviors. However, their association after adjustment was mixed, which could be attributed to a number of factors such as variations in definitions of substance use and gun activity, study design, sample demographics, and the specific covariates considered. Fewer studies identified a significant association between substance use and gun access/possession than other gun activities. The significant association between nonsubstance covariates (e.g., demographic covariates and other behavioral risk factors) and gun-related behaviors might have moderated the association between substance use and gun activities. Particularly, the strength of association between substance use and gun activities tended to reduce appreciably or to become nonsignificant after adjustment for mental disorders. Some studies indicated a positive association between the frequency of substance use and the odds of engaging in gun-related behaviors. Overall, the results suggest a need to consider substance use in research and prevention programs for gun-related violence. © The Author 2016. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Systems Engineering Approach for Conceptual Design of Frigate

DTIC Science & Technology

2015-09-01

ejection area. Topside designers should also take note of the gun maintenance required area (e.g., barrel swabbing area), which requires significant...Figure 9. Range-to-Target Plot (BlueIntercept Missile vs. RedFire) ........................34 Figure 10. Range-to-Target Plot (Main Gun System vs...and the secondary anti-air weapon will be the main gun system. The frigates shall also be equipped with an area terminal type defense (ATTD

Data transmission optical link for RF-GUN project

NASA Astrophysics Data System (ADS)

Olowski, Krzysztof; Zielinski, Jerzy; Jalmuzna, Wojciech; Pozniak, Krzysztof; Romaniuk, Ryszard

2005-09-01

Today, the fast optical data transmission is one of the fundamentals of modern distributed control systems. The fibers are widely use as multi-gigabit data stream medium. For a short range transmission, the multimode fibers are in common use. The data rate for this kind of transmission exceeds 10 Gbps for 10 Gigabit Ethernet and 10G Fibre Channel protocols. The Field Programmable Gate Arrays are one of the opportunities of managing the optical transmission. This article is concerning a synchronous optical transmission system via a multimode fiber. The transmission is controlled by the FPGA of two manufacturers: Xilinx and Altera. This paper contains the newest technology overview and market device parameters. It also describes a board for the optical transmission, technical details of the transmission and optical transmission results.

Racism, Gun Ownership and Gun Control: Biased Attitudes in US Whites May Influence Policy Decisions

PubMed Central

O’Brien, Kerry; Forrest, Walter; Lynott, Dermot; Daly, Michael

2013-01-01

Objective Racism is related to policies preferences and behaviors that adversely affect blacks and appear related to a fear of blacks (e.g., increased policing, death penalty). This study examined whether racism is also related to gun ownership and opposition to gun controls in US whites. Method The most recent data from the American National Election Study, a large representative US sample, was used to test relationships between racism, gun ownership, and opposition to gun control in US whites. Explanatory variables known to be related to gun ownership and gun control opposition (i.e., age, gender, education, income, conservatism, anti-government sentiment, southern vs. other states, political identification) were entered in logistic regression models, along with measures of racism, and the stereotype of blacks as violent. Outcome variables included; having a gun in the home, opposition to bans on handguns in the home, support for permits to carry concealed handguns. Results After accounting for all explanatory variables, logistic regressions found that for each 1 point increase in symbolic racism there was a 50% increase in the odds of having a gun at home. After also accounting for having a gun in the home, there was still a 28% increase in support for permits to carry concealed handguns, for each one point increase in symbolic racism. The relationship between symbolic racism and opposition to banning handguns in the home (OR1.27 CI 1.03,1.58) was reduced to non-significant after accounting for having a gun in the home (OR1.17 CI.94,1.46), which likely represents self-interest in retaining property (guns). Conclusions Symbolic racism was related to having a gun in the home and opposition to gun control policies in US whites. The findings help explain US whites’ paradoxical attitudes towards gun ownership and gun control. Such attitudes may adversely influence US gun control policy debates and decisions. PMID:24204867

Racism, gun ownership and gun control: biased attitudes in US whites may influence policy decisions.

PubMed

O'Brien, Kerry; Forrest, Walter; Lynott, Dermot; Daly, Michael

2013-01-01

Racism is related to policies preferences and behaviors that adversely affect blacks and appear related to a fear of blacks (e.g., increased policing, death penalty). This study examined whether racism is also related to gun ownership and opposition to gun controls in US whites. The most recent data from the American National Election Study, a large representative US sample, was used to test relationships between racism, gun ownership, and opposition to gun control in US whites. Explanatory variables known to be related to gun ownership and gun control opposition (i.e., age, gender, education, income, conservatism, anti-government sentiment, southern vs. other states, political identification) were entered in logistic regression models, along with measures of racism, and the stereotype of blacks as violent. Outcome variables included; having a gun in the home, opposition to bans on handguns in the home, support for permits to carry concealed handguns. After accounting for all explanatory variables, logistic regressions found that for each 1 point increase in symbolic racism there was a 50% increase in the odds of having a gun at home. After also accounting for having a gun in the home, there was still a 28% increase in support for permits to carry concealed handguns, for each one point increase in symbolic racism. The relationship between symbolic racism and opposition to banning handguns in the home (OR1.27 CI 1.03,1.58) was reduced to non-significant after accounting for having a gun in the home (OR1.17 CI.94,1.46), which likely represents self-interest in retaining property (guns). Symbolic racism was related to having a gun in the home and opposition to gun control policies in US whites. The findings help explain US whites' paradoxical attitudes towards gun ownership and gun control. Such attitudes may adversely influence US gun control policy debates and decisions.

The HyperV 8000 μg, 50 km/s Plasma Railgun for PLX

NASA Astrophysics Data System (ADS)

Brockington, Samuel; Case, Andrew; Messer, Sarah; Wu, Linchun; Witherspoon, F. Douglas

2012-10-01

HyperV has developed a gas fed, pulsed, plasma railgun which accelerates 8000 μg of argon to 50 km/s meeting the performance requirements originally specified for the Plasma Liner Experiment (PLX). The present 2.5 cm square-bore plasma railgun forms plasma armatures from high density neutral gas, pre-ionizes it electro-thermally, and accelerates the armature with 30 cm long parallel-plate railgun electrodes driven by a pulse forming network (PFN). A high voltage, high current linear array spark-gap switch and flexible, low-inductance transmission line were designed and constructed to handle the increased current load. We will describe these systems and present initial performance data from high current operation of the plasma rail gun from spectroscopy, interferometry, and imaging systems. Measurements of momentum, pressure, magnetic field, and other optical diagnostics will also be discussed as well as plans for upcoming experimentation to increase performance even further. Work supported by USDOE under DE-FG02-05ER54810 and DE-FG02-08ER85114.

America, guns and freedom: Part II — An international perspective

PubMed Central

Faria, Miguel A.

2012-01-01

The need for reducing gun violence is discussed along with the necessity for citizens to assume some responsibility for protecting themselves, their families, and their property from criminal elements because the police cannot physically be everywhere to protect us all of the time. The problem of sensationalization of gun crimes by the media, multiple shootings by deranged individuals, accidents with firearms, suicide rates, and children with guns are discussed. The relationship of civilian disarmament in the context of tyrannical governments and genocide are also explored. Incidents in which liberty has been extinguished because firearms have been banned and citizens have been disarmed by increasingly oppressive governments, and the converse, countries where freedom has been preserved by armed citizens are also described. We conclude that guns in the hands of law-abiding citizens deter crimes, and nations that trust their citizens with firearms have governments that sustain liberty and affirm individual freedom. Governments that do not trust their citizens with firearms tend to be despotic and tyrannical, and are a potential danger to good citizens — and a peril to humanity. PMID:23227440

America, guns and freedom: Part II - An international perspective.

PubMed

Faria, Miguel A

2012-01-01

The need for reducing gun violence is discussed along with the necessity for citizens to assume some responsibility for protecting themselves, their families, and their property from criminal elements because the police cannot physically be everywhere to protect us all of the time. The problem of sensationalization of gun crimes by the media, multiple shootings by deranged individuals, accidents with firearms, suicide rates, and children with guns are discussed.The relationship of civilian disarmament in the context of tyrannical governments and genocide are also explored. Incidents in which liberty has been extinguished because firearms have been banned and citizens have been disarmed by increasingly oppressive governments, and the converse, countries where freedom has been preserved by armed citizens are also described. We conclude that guns in the hands of law-abiding citizens deter crimes, and nations that trust their citizens with firearms have governments that sustain liberty and affirm individual freedom. Governments that do not trust their citizens with firearms tend to be despotic and tyrannical, and are a potential danger to good citizens - and a peril to humanity.

Velocity Measurements on the Electric Gun Developed at the TNO Prins Maurits Laboratory (Snelheidheidsmetingen aan de bij het Prins Maurits Laboratorium Ontwikkelde Electric Gun)

DTIC Science & Technology

1993-03-01

8 2.3 De Flyer Plate Assembly (.FPA) 9 3 OPZET VAN DE MFTThIGEN 11 3.1 De djfferentjaalstroommetiflg 11 3.2 Stroommetingen 12 3.3...25 n11)" II )60 S. L) I.P014 25 ,rzit II ,0 8 9 28 ).7 I 10.7 273.0 2.15 43790 1.318 - - - IM,𔃺I5 25 Nr. 11 60 8.9 279.t) 125.9 274.1 2.22 44406 1...4 HWO-KLU 5 HWO-KM 6 DMKL J.A. van Gool 7/ 9 TDCK 10 Hoofddirecteur DO-TNO 11 Lid Inst jtuuts Advies Raad PMIL Prof. drs. P.J. van den Berg 12 Lid

Injection of a coaxial-gun-produced magnetized plasma into a background helicon plasma

NASA Astrophysics Data System (ADS)

Zhang, Yue; Lynn, Alan; Gilmore, Mark; Hsu, Scott

2014-10-01

A compact coaxial plasma gun is employed for experimental investigation of plasma bubble relaxation into a lower density background plasma. Experiments are being conducted in the linear device HelCat at UNM. The gun is powered by a 120-uF ignitron-switched capacitor bank, which is operated in a range of 5 to 10 kV and 100 kA. Multiple diagnostics are employed to investigate the plasma relaxation process. Magnetized argon plasma bubbles with velocities 1.2Cs, densities 1020 m-3 and electron temperature 13eV have been achieved. The background helicon plasma has density 1013 m-3, magnetic field from 200 to 500 Gauss and electron temperature 1eV. Several distinct operational regimes with qualitatively different dynamics are identified by fast CCD camera images. Additionally a B-dot probe array has been employed to measure the spatial toroidal and poloidal magnetic flux evolution to identify plasma bubble configurations. Experimental data and analysis will be presented.

Multistage Electromagnetic and Laser Launchers for Affordable, Rapid Access to Space

DTIC Science & Technology

2011-07-01

control procedures. To accommodate this, after each gun build, bore gauges were used to accurately measure the bore dimensions , and the projectile...1. Operating Parameters Projectile Mass 5.4 g Bore Dimensions 17 mm × 17 mm Desired Muzzle Speed ~4.5 km/s (3.2m) ~7 km/s (7 m) Gun Length 3.2 m...for a range of ballistic trajectories of interest to the gun launch. The aeroshell dimensions were chosen as being typical for the launch mass

40 CFR 63.806 - Recordkeeping requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... guns showing total finishing material usage and the percentage of finishing materials applied with conventional air spray guns for each semiannual period as required by § 63.803(h)(5). (5) Records associated...) or (g)(4) shall maintain copies of the calculations demonstrating that the overall control efficiency...

A new evaluation method of electron optical performance of high beam current probe forming systems.

PubMed

Fujita, Shin; Shimoyama, Hiroshi

2005-10-01

A new numerical simulation method is presented for the electron optical property analysis of probe forming systems with point cathode guns such as cold field emitters and the Schottky emitters. It has long been recognized that the gun aberrations are important parameters to be considered since the intrinsically high brightness of the point cathode gun is reduced due to its spherical aberration. The simulation method can evaluate the 'threshold beam current I(th)' above which the apparent brightness starts to decrease from the intrinsic value. It is found that the threshold depends on the 'electron gun focal length' as well as on the spherical aberration of the gun. Formulas are presented to estimate the brightness reduction as a function of the beam current. The gun brightness reduction must be included when the probe property (the relation between the beam current l(b) and the probe size on the sample, d) of the entire electron optical column is evaluated. Formulas that explicitly consider the gun aberrations into account are presented. It is shown that the probe property curve consists of three segments in the order of increasing beam current: (i) the constant probe size region, (ii) the brightness limited region where the probe size increases as d approximately I(b)(3/8), and (iii) the angular current intensity limited region in which the beam size increases rapidly as d approximately I(b)(3/2). Some strategies are suggested to increase the threshold beam current and to extend the effective beam current range of the point cathode gun into micro ampere regime.

Development of a Telemetry-Enabled High-G Projectile Carrier

DTIC Science & Technology

2012-09-01

of High Velocity Guns, Version 2 (IBHVG2) interior ballistics simulation • Pete Muller, ARL, helped populate the ARL sensor suite boards...differences in external characteristics between the conventional M831 and the modified M831 high-g carrier projectile can be seen in figure 3. Figure 2...of High Velocity Guns, Version 2 (IBHVG2) (6). The output values from the simulation for the selected charge weight are seen in table 2. Table 2

Micrometeorite Impact Test of Flex Solar Array Coupon

NASA Technical Reports Server (NTRS)

Wright, K. H.; Schneider, T. A.; Vaughn, J. A.; Hoang, B.; Wong, F.; Gardiner, G.

2016-01-01

Spacecraft with solar arrays operate throughout the near earth environment and are planned for outer planet missions. An often overlooked test condition for solar arrays that is applicable to these missions is micrometeoroid impacts and possibly electrostatic discharge (ESD) events resulting from these impacts. NASA Marshall Space Flight Center (MSFC) is partnering with Space Systems/Loral, LLC (SSL) to examine the results of simulated micrometeoroid impacts on the electrical performance of an advanced, lightweight flexible solar array design. The test is performed at MSFC's Micro Light Gas Gun Facility with SSL-provided coupons. Multiple impacts were induced at various locations on a powered test coupon under different string voltage (0V-150V) and string current (1.1A - 1.65A) conditions. The setup, checkout, and results from the impact testing are discussed.

Overview of the Calcium-45 Beta Spectrum Measurement at Los Alamos National Laboratory

NASA Astrophysics Data System (ADS)

Royse, Camen; Nab/UNCB Teams Collaboration

2017-09-01

One smoking gun of BSM physics would be the observation of a non-zero Fierz interference term, a feature in the beta spectrum produced by scalar and tensor couplings. Calcium-45 is an almost ideal candidate with which to search for a Fierz term. It is a pure beta emitter with a low endpoint of 256 keV and a simple decay scheme, with a 7 / 2 - -> 7 / 2 - g.s. to g.s. branching ratio of 99.9981(11)%. Isospin selection rules ensure the decay is greater than about 98.5% pure Gamow-Teller and the integrated effect of the weak magnetism over the entire spectrum is expected to be only 0.13%. An experiment designed to precisely measure the beta spectrum of Ca-45 has been run over the past two summers at Los Alamos National Laboratory. The experiment is composed of a 4 π-capture magnetic spectrometer between two segmented arrays of hexagonal silicon detectors (similar to the Nab experiment), a helium gas cooling system, front end electronics and amplifiers, and a data acquisition system which synchronizes the timing from the signals coming from both detector arrays. Data is analyzed to account for the pile-up of signals and other physical and calibration factors. An overview of the design and execution of the experiment as divided into the above topics will be presented.

Noise Hazard Evaluation Sound Level Data on Noise Sources

DTIC Science & Technology

1975-01-01

Saw, Root Woodworking 43-20-J 102 16. Construction Saw, DeWalt Industrial 2185A 96 17. Cross-Cut Sw, Automatic 1-H 94 18, Cross-Cut Saw, DeWalt 3561...Saw, GM Diehr 750 92 53. Rip Saw, Wabach Industrial 750 97 59. Rip Saw, Yates American B. 102 60. Router: Black & Decker 118 61. Ruuter, Rockwell 150B...13. Sander, Disk, National-Detroit Dual Action 100 14. Stapler , Senco Mll 94* 15. Stapling Gun, Bostich II 105* 16. Stapling Gun, Bostich III 104* 17

Basic Studies on Electro-Energetic Physics (EEP) Weapons Technologies

DTIC Science & Technology

2015-01-15

Po\\\\ered Microwa\\e. High Energ) Laser. Charged Particle Beams. and II) pcrsonic Rail guns . Using these representations. wargame simulations of’ arious...Projectile length = 30 in (76 cm) • Barrel length = 10 m • Muzzle velocity = 2,100 m/s To understand how such an advanced weapon compares with conventional...weaponry, it is illustrating to compare these figures with the M-1 Abrams M256 120mm gun firing a M829A1 kinetic energy round Page 5 • Muzzle

The Coast Artillery Journal. Volume 76, Number 3, May-June 1933

DTIC Science & Technology

1933-06-01

playthings as " Tommy -Guns." We will now discuss the subject of the Machine Gun in riot service. Although this weapon, fortunately, has never been used...Benjamin Bowering, student, C. & G. S. School, Ft. Leavenworth, to 62d, Ft. Totten , June 30. Captain James D. Brown, student, C. A. School, Ft. Monroe...G. S. School, Ft. Leavenworth, to 62d, Ft. Totten , June 30. Captain Lloyd W. Goeppert, student, C. A. School, Ft. Monroe, to 63d, Ft. MacArthur

Estimates of auditory risk from outdoor impulse noise. II: Civilian firearms.

PubMed

Flamme, Gregory A; Wong, Adam; Liebe, Kevin; Lynd, James

2009-01-01

Firearm impulses are common noise exposures in the United States. This study records, describes and analyzes impulses produced outdoors by civilian firearms with respect to the amount of auditory risk they pose to the unprotected listener under various listening conditions. Risk estimates were obtained using three contemporary damage risk criteria (DRC) including a waveform parameter-based approach (peak SPL and B-duration), an energy-based criterion (A-weighted SEL and equivalent continuous level) and a physiological model (AHAAH). Results from these DRC were converted into a number of maximum permissible unprotected exposures to facilitate interpretation. Acoustic characteristics of firearm impulses differed substantially across guns, ammunition, and microphone location. The type of gun, ammunition and the microphone location all significantly affected estimates of auditory risk from firearms. Vast differences in maximum permissible exposures were observed; the rank order of the differences varied with the source of the impulse. Unprotected exposure to firearm noise is not recommended, but people electing to fire a gun without hearing protection should be advised to minimize auditory risk through careful selection of ammunition and shooting environment. Small-caliber guns with long barrels and guns loaded with the least powerful ammunition tend to be associated with the least auditory risk.

KSC-97PC1129

NASA Image and Video Library

1997-07-24

Applied Physics Laboratory engineers and technicians from Johns Hopkins University test solar array deployment of the Advanced Composition Explorer (ACE) in KSC’s Spacecraft Assembly and Encapsulation Facility-II (SAEF-II). The wire hanging from the ceiling above the black solar array panel is used for "g-negation," which takes the weight off of the panel’s hinges to simulate zero gravity, mimicking deployment in space. Scheduled for launch on a Delta II rocket from Cape Canaveral Air Station on Aug. 25, ACE will study low-energy particles of solar origin and high-energy galactic particles for a better understanding of the formation and evolution of the solar system as well as the astrophysical processes involved. The collecting power of instrumentation aboard ACE is at least 100 times more sensitive than anything previously flown to collect similar data by NASA

Reduction of 5in./54 Gun Blast Overpressure by Means of an Aqueous Foam- Filled Muzzle Device

DTIC Science & Technology

1981-08-01

aqueous foams have a certain drainage rate that causes the expansion ratio and bubble size to increase progressively. The Rockwood Aquafoam AFFF yields the...NSWC TR 81-128 REDUCTION OF 5"/54 GUN BLAST OVERPRESSURE BY MEANS OF AN AQUEOUS FOAM -FILLED MUZZLE DEVICE by G. STEVENS MILLER RICHARD E. MILLER, JR...128 4. TITLE (ad Subtitle) S. TYPE O r REPORT & PERIOD COVERED REDUCTION OF 5!V54 GUN BLAST OVERPRESSURE Final BY MEANS OF AN AQUEOUS FOAM -FILLED a

Current distribution measurements inside an electromagnetic plasma gun operated in a gas-puff mode.

PubMed

Poehlmann, Flavio R; Cappelli, Mark A; Rieker, Gregory B

2010-12-01

Measurements are presented of the time-dependent current distribution inside a coaxial electromagnetic plasma gun. The measurements are carried out using an array of six axially distributed dual-Rogowski coils in a balanced circuit configuration. The radial current distributions indicate that operation in the gas-puff mode, i.e., the mode in which the electrode voltage is applied before injection of the gas, results in a stationary ionization front consistent with the presence of a plasma deflagration. The effects of varying the bank capacitance, transmission line inductance, and applied electrode voltage were studied over the range from 14 to 112 μF, 50 to 200 nH, and 1 to 3 kV, respectively.

Current distribution measurements inside an electromagnetic plasma gun operated in a gas-puff mode

PubMed Central

Poehlmann, Flavio R.; Cappelli, Mark A.; Rieker, Gregory B.

2010-01-01

Measurements are presented of the time-dependent current distribution inside a coaxial electromagnetic plasma gun. The measurements are carried out using an array of six axially distributed dual-Rogowski coils in a balanced circuit configuration. The radial current distributions indicate that operation in the gas-puff mode, i.e., the mode in which the electrode voltage is applied before injection of the gas, results in a stationary ionization front consistent with the presence of a plasma deflagration. The effects of varying the bank capacitance, transmission line inductance, and applied electrode voltage were studied over the range from 14 to 112 μF, 50 to 200 nH, and 1 to 3 kV, respectively. PMID:21267082

Plasma-gun-assisted field-reversed configuration formation in a conical θ-pinch

NASA Astrophysics Data System (ADS)

Weber, T. E.; Intrator, T. P.; Smith, R. J.

2015-04-01

Injection of plasma via an annular array of coaxial plasma guns during the pre-ionization phase of field-reversed configuration (FRC) formation is shown to catalyze the bulk ionization of a neutral gas prefill in the presence of a strong axial magnetic field and change the character of outward flux flow during field-reversal from a convective process to a much slower resistive diffusion process. This approach has been found to significantly improve FRC formation in a conical θ-pinch, resulting in a ˜350% increase in trapped flux at typical operating conditions, an expansion of accessible formation parameter space to lower densities and higher temperatures, and a reduction or elimination of several deleterious effects associated with the pre-ionization phase.

Gestational undernourishment modifies the composition of skeletal muscle transverse tubule membranes and the mechanical properties of muscles in newborn rats.

PubMed

Ramírez-Oseguera, Ricardo Tonathiu; Jiménez-Garduño, Aura Matilde; Alvarez, Rocío; Heine, Katharina; Pinzón-Estrada, Enrique; Torres-Saldaña, Ismael; Ortega, Alicia

2013-01-01

[corrected] Skeletal muscle (SM) constitutes more than 40% of the body weight in adulthood. Transports dietary glucose mainly through the insulin-dependent glucose transporter (Glut-4) located in the Transverse tubule membrane system (TT). The TT development ends shortly after birth. The TT membrane hosts the proteins involved in excitation-contraction coupling and glucose uptake. Glycaemic regulation through movement is a key function of fully developed skeletal muscle. In this study, we aimed to characterize the effect of gestational undernourishment (GUN) in rats GLUT-4 expression and on the protein/lipid content of the TT membranes. We also examined the effect of GUN on the mechanical properties of muscles as an indication of the metabolic condition of the SM at birth. Isolated TT membrane from SM of GUN rats were used to study lipid/protein content and protein stability by differential scanning calorimetry. The effect of GUN on the SM mechanical properties was determined in isolated Extensor Digitorum Longus (EDL) muscle. We demonstrate that compared to control, GUN in the new-born produces; i) decreases body weight; ii) diminution in SM mass; iii) decreases the formation of TT membranes; iv) expresses TT membrane proteins with higher thermal stability. The TT membrane expression of GLUT-4 in GUN offspring was twice that of controls. The isolated EDL of GUN offspring was 20% stronger as measured by contractile force and more resistant to fatigue relative to controls. These results provide the first evidence of adaptive changes of the SM in new-borns exposed to severe gestational food restriction. The effects of GUN on muscle at birth are the first step toward detrimental SM metabolic function, contributing to the physiopathology of metabolic diseases in adulthood. © 2013 S. Karger AG, Basel

Triple seismic source, double research ship, single ambitious goal: integrated imaging of young oceanic crust in the Panama Basin

NASA Astrophysics Data System (ADS)

Wilson, Dean; Peirce, Christine; Hobbs, Richard; Gregory, Emma

2016-04-01

Understanding geothermal heat and mass fluxes through the seafloor is fundamental to the study of the Earth's energy budget. Using geophysical, geological and physical oceanography data we are exploring the interaction between the young oceanic crust and the ocean in the Panama Basin. We acquired a unique geophysical dataset that will allow us to build a comprehensive model of young oceanic crust from the Costa Rica Ridge axis to ODP borehole 504B. Data were collected over two 35 x 35 km2 3D grid areas, one each at the ridge axis and the borehole, and along three 330 km long 2D profiles orientated in the spreading direction, connecting the two grids. In addition to the 4.5 km long multichannel streamer and 75 ocean-bottom seismographs (OBS), we also deployed 12 magnetotelluric (MT) stations and collected underway swath bathymetry, gravity and magnetic data. For the long 2D profiles we used two research vessels operating synchronously. The RRS James Cook towed a high frequency GI-gun array (120 Hz) to image the sediments, and a medium frequency Bolt-gun array (50 Hz) for shallow-to-mid-crustal imaging. The R/V Sonne followed the Cook, 9 km astern and towed a third seismic source; a low frequency, large volume G-gun array (30 Hz) for whole crustal and upper mantle imaging at large offsets. Two bespoke vertical hydrophone arrays recorded real far field signatures that have enabled us to develop inverse source filters and match filters. Here we present the seismic reflection image, forward and inverse velocity-depth models and a density model along the primary 330 km north-south profile, from ridge axis to 6 Ma crust. By incorporating wide-angle streamer data from our two-ship, synthetic aperture acquisition together with traditional wide-angle OBS data we are able to constrain the structure of the upper oceanic crust. The results show a long-wavelength trend of increasing seismic velocity and density with age, and a correlation between velocity structure and basement roughness. Increased basement roughness leads to a non-uniform distribution of sediments, which we hypothesise influences the pattern of hydrothermal circulation and ultimately the secondary alteration of the upper crust. A combination of the complimentary wide-angle and normal incidence datasets and their individual models act as a starting point for joint inversion of seismic, gravity and MT data. The joint inversion produces a fully integrated model, enabling us to better understand how the oceanic crust evolves as a result of hydrothermal fluid circulation and cooling, as it ages from zero-age at the ridge-axis to 6 Ma at borehole 504B. Ultimately, this model can be used to undertake full waveform inversion to produce a high-resolution velocity model of the oceanic crust in the Panama Basin. This research is part of a major, interdisciplinary NERC-funded research collaboration entitled: Oceanographic and Seismic Characterisation of heat dissipation and alteration by hydrothermal fluids at an Axial Ridge (OSCAR).

Gun muzzle flash detection using a single photon avalanche diode array in 0.18µm CMOS technology

NASA Astrophysics Data System (ADS)

Savuskan, Vitali; Jakobson, Claudio; Merhav, Tomer; Shoham, Avi; Brouk, Igor; Nemirovsky, Yael

2015-05-01

In this study, a CMOS Single Photon Avalanche Diode (SPAD) 2D array is used to record and sample muzzle flash events in the visible spectrum, from representative weapons. SPADs detect the emission peaks of alkali salts, potassium or sodium, with spectral emission lines around 769nm and 589nm, respectively. The alkali salts are included in the gunpowder to suppress secondary flashes ignited during the muzzle flash event. The SPADs possess two crucial properties for muzzle flash imaging: (i) very high photon detection sensitivity, (ii) a unique ability to convert the optical signal to a digital signal at the source pixel, thus practically eliminating readout noise. The sole noise sources are the ones prior to the readout circuitry (optical signal distribution, avalanche initiation distribution and nonphotonic generation). This enables high sampling frequencies in the kilohertz range without significant SNR degradation, in contrast to regular CMOS image sensors. This research will demonstrate the SPAD's ability to accurately sample and reconstruct the temporal behavior of the muzzle flash in the visible wavelength, in the presence of sunlight. The reconstructed signal is clearly distinguishable from background clutter, through exploitation of flash temporal characteristics and signal processing, which will be reported. The frame rate of ~16 KHz was chosen as an optimum between SNR degradation and temporal profile recognition accuracy. In contrast to a single SPAD, the 2D array allows for multiple events to be processed simultaneously. Moreover, a significant field of view is covered, enabling comprehensive surveillance and imaging.

Mitchells Over the Pacific: The Dynamics of B-25 Innovation

DTIC Science & Technology

2013-06-01

began modifying the B- 25 to increase its self -defense capability. The B-25B was the version employed by the Army Air Forces (AAF) during its first...guns in the nose, waist, and floor along with a .50-caliber machine gun in the tail.31 Internally, the B-25A added armor for the aircrew and self ...Forces in World War II, vol. 1, 439. 50 Doyle, B-25 Mitchell, 10. 19 within the aircraft with a 160-gallon rubber fuel bag and ten five-gallon fuel

A Uniaxial Nonlinear Thermoviscoelastic Constitutive Model with Damage for M30 Gun Propellant

DTIC Science & Technology

1994-06-01

Gun Propellants at High Pressure." Lawrence Livermore National Laboratory, UCRL -88521, 1983. n g Design - k _ ao tics of Gum-’ AMCP 706-150, U.S. Army...07806-5000 Bethesda, MD 20054-5000 2 Commander 5 Director DARPA Lawrence Livermore National ATTN: J. Kelly Laboratory B. Wilcox ATTN: R. Christensen 3701

Constance mirror program: Progress and plans

NASA Technical Reports Server (NTRS)

Klinkowstein, R. E.; Mauel, M. E.; Irby, J. H.; Smullin, L. D.; Voldman, S. H.

1981-01-01

The current state of the mechanics of the Constance II experiment, the physics results gathered, the motivation background, and future plans for the Constance II experiment are reviewed. Several improvements have been made and several experimental investigations have been completed. These include the construction/installation/testing of: (1) liquid-nitrogen cooled, Ioffe bars installed, (2) a diverter coil (3) the 100 kW ICRF generator, (4) the data acquisition system, and (5) the optimum hot-iron operation of the machine with Titanium and pulsed-gas plasma guns. Measurements were made of the density, temperature, and radius of the plasma. Ion-cyclotron fluctuations were observed, their bandwidth measured, and data collected demonstrating resonance heating. New X-ray diagnostics were designed and purchased, and progress on the Thomson scattering was made. Finally, a new hot cathode gun was designed and constructed.

Plasma Liner Research for MTF at NASA Marshall Space Flight Center

NASA Technical Reports Server (NTRS)

Thio, Y. C. F.; Eskridge, R.; Lee, M.; Martin, A.; Smith, J.; Cassibry, J. T.; Wu, S. T.; Kirkpatrick, R. C.; Knapp, C. E.; Turchi, P. J.;

Experimental investigation of plasma relaxation using a compact coaxial magnetized plasma gun in a background plasma

NASA Astrophysics Data System (ADS)

Zhang, Yue; Lynn, Alan; Gilmore, Mark; Hsu, Scott; University of New Mexico Collaboration; Los Alamos National Laboratory Collaboration

2013-10-01

A compact coaxial plasma gun is employed for experimental studies of plasma relaxation in a low density background plasma. Experiments are being conducted in the linear HelCat device at UNM. These studies will advance the knowledge of basic plasma physics in the areas of magnetic relaxation and space and astrophysical plasmas, including the evolution of active galactic jets/radio lobes within the intergalactic medium. The gun is powered by a 120pF ignitron-switched capacitor bank which is operated in a range of 5-10 kV and ~100 kA. Multiple diagnostics are employed to investigate plasma relaxation process. Magnetized Argon plasma bubbles with velocities ~1.2Cs and densities ~1020 m-3 have been achieved. Different distinct regimes of operation with qualitatively different dynamics are identified by fast CCD camera images, with the parameter determining the operation regime. Additionally, a B-dot probe array is employed to measure the spatial toroidal and poloidal magnetic flux evolution to identify detached plasma bubble configurations. Experimental data and analysis will be presented.

Evaluating the impact of seismic prospecting on artisanal shrimp fisheries

NASA Astrophysics Data System (ADS)

Andriguetto-Filho, José M.; Ostrensky, Antonio; Pie, Marcio R.; Silva, Ubiratã A.; Boeger, Walter A.

2005-09-01

The constant need to discover new hydrocarbon deposits is causing the use of air-guns to become a very widespread method of seismic prospecting. However, there is still disagreement regarding their impact on the marine environment. This uncertainty is particularly severe in the case of shellfish, which account for a substantial share of commercial fisheries and seafood trade in many parts of the world. In this paper we report on the first study to explicitly assess the impact of seismic prospecting on shrimp resources. We measured bottom trawl yields of a nonselective commercial shrimp fishery comprising the Southern white shrimp, Litopenaeus schmitti, the Southern brown shrimp, Farfantepenaeus subtilis, and the Atlantic Seabob, Xyphopenaeus kroyeri (Decapoda: Penaeidae), before and after the use of an array of four synchronized air-guns, each with 635 in 3 of total capacity, 2.000 psi, and peak pressure of 196 dB (re 1 μPa at 1 m). Our results did not detect significant deleterious impact of seismic prospecting on the studied species, suggesting that shrimp stocks are resilient to the disturbance by air-guns under our experimental conditions.

Pegasus power system facility upgrades

NASA Astrophysics Data System (ADS)

Lewicki, B. T.; Kujak-Ford, B. A.; Winz, G. R.

2008-11-01

Two key Pegasus systems have been recently upgraded: the Ohmic-transformer IGCT bridge control system, and the plasma-gun injector power system. The Ohmic control system contains two new microprocessor controlled components to provide an interface between the PWM controller and the IGCT bridges. An interface board conditions the command signals from the PWM controller. A splitter/combiner board routes the conditioned PWM commands to an array of IGCT bridges and interprets IGCT bridge status. This system allows for any PWM controller to safely control IGCT bridges. Future developments will include a transition to a polyphasic bridge control. This will allow for 3 to 4 times the present pulse length and provide a much higher switching frequency. The plasma gun injector system now includes active current feedback control on gun bias current via PWM buck type power supplies. Near term goals include a doubling or tripling of the applied bias voltage. Future arc bias system power supplies may include a simpler boost type system which will allow access to even higher voltages using existing low voltage energy storage systems.

A review of micromirror arrays

DOE PAGES

Song, Yuanping; Panas, Robert M.; Hopkins, Jonathan B.

2017-08-30

The aim of this article is to provide a review of micromirror array (MMA) technologies (2631 MMA research papers and patents were reviewed for this effort). The performance capabilities of 277 MMA designs from 49 companies and 23 academic research groups are categorized and compared. The designs are categorized according to (i) their array’s dimension (e.g., 2D arrays consisting of mirrors that cover a surface, 1D arrays consisting of mirrors in a row, and 0D arrays consisting of only a single mirror), (ii) the nature of the surface of their mirrors (e.g., continuous or discrete), (iii) what combination of tip,more » tilt, and/or piston degrees of freedom (DOFs) they achieve, and (iv) how they are actuated. Standardized performance metrics that can be systematically applied to every MMA design (e.g., mirror area, fill factor, pitch, range of motion, maximum acceleration, actuator energy density, and number of uncontrolled DOFs) are defined and plotted for existing designs to enable their fair comparison. Theoretical bounds on what is physically possible for MMAs to achieve are also derived and depicted in these plots to highlight the amount of performance improvement that remains to be achieved by future designs and guidelines are provided to aid in the development of these future designs.« less

A review of micromirror arrays

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

Song, Yuanping; Panas, Robert M.; Hopkins, Jonathan B.

The aim of this article is to provide a review of micromirror array (MMA) technologies (2631 MMA research papers and patents were reviewed for this effort). The performance capabilities of 277 MMA designs from 49 companies and 23 academic research groups are categorized and compared. The designs are categorized according to (i) their array’s dimension (e.g., 2D arrays consisting of mirrors that cover a surface, 1D arrays consisting of mirrors in a row, and 0D arrays consisting of only a single mirror), (ii) the nature of the surface of their mirrors (e.g., continuous or discrete), (iii) what combination of tip,more » tilt, and/or piston degrees of freedom (DOFs) they achieve, and (iv) how they are actuated. Standardized performance metrics that can be systematically applied to every MMA design (e.g., mirror area, fill factor, pitch, range of motion, maximum acceleration, actuator energy density, and number of uncontrolled DOFs) are defined and plotted for existing designs to enable their fair comparison. Theoretical bounds on what is physically possible for MMAs to achieve are also derived and depicted in these plots to highlight the amount of performance improvement that remains to be achieved by future designs and guidelines are provided to aid in the development of these future designs.« less

Detection of Sagittarius A* at 330 MHz With the Very Large Array

DTIC Science & Technology

2004-01-20

our Galaxy’s central massive black hole , at 330 MHz with the Very Large Array. Implications for the spectrum and emission processes of Sgr A * are... A East, the Sgr A West H ii region, and Sgr A *, recently established as our Galaxy’s central massive black hole (e.g., Ghez et al. 2000; Eckart et al...toward Sgr A *. This could be explained by a localized clearing of the ambient gas accomplished either through the direct influence of the black hole

Prevalence and Density of Digenetic Trematode Metacercariae in Clams and Oysters from Western Coastal Regions of the Republic of Korea.

PubMed

Sohn, Woon-Mok; Na, Byoung-Kuk; Cho, Shin-Hyeong; Lee, Won-Ja

2017-08-01

A survey was performed to know the recent infection status of digenetic trematode metacercariae in clams and oysters from 4 sites in western coastal regions of the Republic of Korea (=Korea). Four species of clams (Mactra veneriformis, Ruditapes philippinarum, Cyclina sinensis, and Saxidomus purpuratus) were collected from Taean-gun, Chungcheongnam-do (Province), Buan-gun (County) and Gochang-gun, Jeollabuk-do, and oysters, Crassostrea gigas, from Shinan-gun, Jeollanam-do were transferred to our laboratory on ice and examined by the artificial digestion method. The metacercariae of Himasthla alincia were detected in 3 species of clams, M. veneriformis, R. philippinarum, and C. sinensis from the 3 surveyed areas. The positive rate and the mean density per clam infected were 98.9% (30.8 metacercariae) in M. veneriformis, 60.0% (5.0) in R. philippinarum, and 96.0% (28.4) in C. sinensis. The positive rate (mean density) of Acanthoparyphium tyosenense metacercariae in M. veneriformis was 50.0% (2.1) from Taean-gun and 70.0% (2.8) from Gochang-gun. The metacercariae of Parvatrema spp. were detected in M. veneriformis and R. philippinarum from Taean-gun and Gochang-gun; the positive rate (mean density) was 63.3% (4,123) and 50.0% (19) in M. veneriformis, and 6.7% (126) and 100% (238) in R. philippinarum from the 2 regions, respectively. The metacercariae of Gymnophalloides seoi were detected in all 30 oysters from Shinan-gun, and their average density per oyster was 646. From the above results, it has been confirmed that more than 3 species of metacercariae are prevalent in clams from the western coastal regions, and G. seoi metacercariae are still prevalent in oysters from Shinan-gun, Jeollanam-do, Korea.

Plasma-gun-assisted field-reversed configuration formation in a conical θ-pinch

DOE PAGES

Weber, T. E.; Intrator, T. P.; Smith, R. J.

2015-04-29

We show through injection of plasma via an annular array of coaxial plasma guns, during the pre-ionization phase of field-reversed configuration (FRC) formation how to catalyze the bulk ionization of a neutral gas prefill in the presence of a strong axial magnetic field and change the character of outward flux flow during field-reversal from a convective process to a much slower resistive diffusion process. Our approach has been found to significantly improve FRC formation in a conical θ-pinch, resulting in a ~350% increase in trapped flux at typical operating conditions, an expansion of accessible formation parameter space to lower densitiesmore » and higher temperatures, and a reduction or elimination of several deleterious effects associated with the pre-ionization phase.« less

Plasma-gun-assisted field-reversed configuration formation in a conical θ-pinch

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

Weber, T. E., E-mail: tweber@lanl.gov; Intrator, T. P.; Smith, R. J.

2015-04-15

Injection of plasma via an annular array of coaxial plasma guns during the pre-ionization phase of field-reversed configuration (FRC) formation is shown to catalyze the bulk ionization of a neutral gas prefill in the presence of a strong axial magnetic field and change the character of outward flux flow during field-reversal from a convective process to a much slower resistive diffusion process. This approach has been found to significantly improve FRC formation in a conical θ-pinch, resulting in a ∼350% increase in trapped flux at typical operating conditions, an expansion of accessible formation parameter space to lower densities and highermore » temperatures, and a reduction or elimination of several deleterious effects associated with the pre-ionization phase.« less

DefenseLink Special: Veterans Day 2006

Science.gov Websites

this hour, our nation remembers the moment when the guns of World War I went silent -- and we recognize ;Doolittle Raiders," former Army Air Corpsmen who were part of a famed World War II bombing mission over servicemembers. It will conclude Nov. 11 with the 72nd annual Veterans Day Parade. Story World War II Air Crash

Assessing views about gun violence reduction policy: a look at type of violence and expected effectiveness.

PubMed

Sorenson, Susan B

2015-10-01

Public opinion polling about gun policy is routinely conducted and often disregarded. The purpose of this research is to explore ways in which surveys can be made more useful to policy makers, researchers, and the general public. A stratified random sample of 1000 undergraduates at a private, urban university was recruited for an online survey about proposed gun policies. A total of 51.7% answered the questions analyzed herein. Including but going beyond typical assessments of agreement, the survey elicited respondent evaluations of the effectiveness of seven gun policies under two randomly assigned conditions: the type of gun violence (e.g., homicide, suicide, violent crime) and its magnitude. Participants were asked to estimate the effectiveness of each policy, including the possibility of making things worse. Participants indicated strong support for all policies and expected each to be effective with one exception - a policy designed to increase the number of guns on the scene, that is, putting armed police in schools. Persons who did not support other policies, on average, did not expect them to make things worse. Telling participants about the scope of the violence did not but the type of gun violence did affect effectiveness ratings. Asking about expected effectiveness of (vs. general support for) a policy might identify some optimism: Even people who don't support a policy sometimes think it will be effective. Findings suggest that surveys about the effectiveness of gun violence policies likely assess views that exclude suicide, the most common form of gun-related mortality. Copyright © 2015 Elsevier Inc. All rights reserved.

Mapping the fine structure of cortical activity with different micro-ECoG electrode array geometries

NASA Astrophysics Data System (ADS)

Wang, Xi; Gkogkidis, C. Alexis; Iljina, Olga; Fiederer, Lukas D. J.; Henle, Christian; Mader, Irina; Kaminsky, Jan; Stieglitz, Thomas; Gierthmuehlen, Mortimer; Ball, Tonio

2017-10-01

Objective. Innovations in micro-electrocorticography (µECoG) electrode array manufacturing now allow for intricate designs with smaller contact diameters and/or pitch (i.e. inter-contact distance) down to the sub-mm range. The aims of the present study were: (i) to investigate whether frequency ranges up to 400 Hz can be reproducibly observed in µECoG recordings and (ii) to examine how differences in topographical substructure between these frequency bands and electrode array geometries can be quantified. We also investigated, for the first time, the influence of blood vessels on signal properties and assessed the influence of cortical vasculature on topographic mapping. Approach. The present study employed two µECoG electrode arrays with different contact diameters and inter-contact distances, which were used to characterize neural activity from the somatosensory cortex of minipigs in a broad frequency range up to 400 Hz. The analysed neural data were recorded in acute experiments under anaesthesia during peripheral electrical stimulation. Main results. We observed that µECoG recordings reliably revealed multi-focal cortical somatosensory response patterns, in which response peaks were often less than 1 cm apart and would thus not have been resolvable with conventional ECoG. The response patterns differed by stimulation site and intensity, they were distinct for different frequency bands, and the results of functional mapping proved independent of cortical vascular. Our analysis of different frequency bands exhibited differences in the number of activation peaks in topographical substructures. Notably, signal strength and signal-to-noise ratios differed between the two electrode arrays, possibly due to their different sensitivity for variations in spatial patterns and signal strengths. Significance. Our findings that the geometry of µECoG electrode arrays can strongly influence their recording performance can help to make informed decisions that maybe important in number of clinical contexts, including high-resolution brain mapping, advanced epilepsy diagnostics or brain-machine interfacing.

Flame Temperatures and Internal Pressures of Pyrotechnic Igniters Used in Liquid Propellant Gun Firings

DTIC Science & Technology

1982-03-01

IP AT 655 ~~I . . . . . 45 7 I. INTRODUCTION The lack of quantitative ignition design criteria in liquid propellant gun firings requires the...Meeting~ CPIA PubUaation No. :300~ VoZ . I, AppUed Physias Laboratory~ SiZver Spring~ MD~ p. :39:3 (19?9). 26 REFERENCES 1. J. D. Knapton, I. C. Stobie...T9E6 Igniter and a Booster Charge of M30 and Eimite !I I ll[[l 1!13 IP -111 .. Sll tiiiiML I RRX-P.D. !1252 I ~· s 1: 31~ 211 z II Figure B2

Lead salt room-temperature MWIR FPA

NASA Astrophysics Data System (ADS)

Murphy, Paul F.; Jost, Steven R.; Barrett, John L.; Reese, Dan; Winn, Michael L.

2001-10-01

The development of low-cost uncooled thermal LWIR FPAs is resulting in the emergence of a new generation of infrared sensors for applications where affordability is the prerequisite for volume production. Both ferroelectric detector arrays and silicon-based microbolometers are finding numerous applications from gun sights to automotive FLIRs. There would be significant interest in a similar uncooled offering in the MWIR, but to date, thermal detectors have lacked sufficient sensitivity. The existing uncooled MWIR photon detector technology, based on polycrystalline lead salts, has been relegated to single-element detectors and relatively small linear arrays due to the high dark current and the stigma of being a 50-year-old technology.

75 FR 32379 - Takes of Marine Mammals Incidental to Specified Activities; Taking Marine Mammals Incidental to...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-08

[email protected] . NMFS is not responsible for e mail comments sent to addresses other than the one... 12, 2010. The April 12, 2010, application is the one available for public comment (see ADDRESSES) and... will be used as spares. One of the smallest guns in the array (60 in\\3\\) will be used as the mitigation...

Experimental Charging Behavior of Orion UltraFlex Array Designs

NASA Technical Reports Server (NTRS)

Golofaro, Joel T.; Vayner, Boris V.; Hillard, Grover B.

2010-01-01

The present ground based investigations give the first definitive look describing the charging behavior of Orion UltraFlex arrays in both the Low Earth Orbital (LEO) and geosynchronous (GEO) environments. Note the LEO charging environment also applies to the International Space Station (ISS). The GEO charging environment includes the bounding case for all lunar mission environments. The UltraFlex photovoltaic array technology is targeted to become the sole power system for life support and on-orbit power for the manned Orion Crew Exploration Vehicle (CEV). The purpose of the experimental tests is to gain an understanding of the complex charging behavior to answer some of the basic performance and survivability issues to ascertain if a single UltraFlex array design will be able to cope with the projected worst case LEO and GEO charging environments. Stage 1 LEO plasma testing revealed that all four arrays successfully passed arc threshold bias tests down to -240 V. Stage 2 GEO electron gun charging tests revealed that only the front side area of indium tin oxide coated array designs successfully passed the arc frequency tests

Diolistic labeling of neuronal cultures and intact tissue using a hand-held gene gun

PubMed Central

O'Brien, John A; Lummis, Sarah CR

2009-01-01

Diolistic labeling is a highly efficient method for introducing dyes into cells using biolistic techniques. The use of lipophilic carbocyanine dyes, combined with particle-mediated biolistic delivery using a hand-held gene gun, allows non-toxic labeling of multiple cells in both living and fixed tissue. The technique is rapid (labeled cells can be visualized in minutes) and technically undemanding. Here, we provide a detailed protocol for diolistic labeling of cultured human embryonic kidney 293 cells and whole brain using a hand-held gene gun. There are four major steps: (i) coating gold microcarriers with one or more dyes; (ii) transferring the microcarriers into a cartridge to make a bullet; (iii) preparation of cells or intact tissue; and (iv) firing the microcarriers into cells or tissue. The method can be readily adapted to other cell types and tissues. This protocol can be completed in less than 1 h. PMID:17406443

Powers of Persuasion--Poster Art of World War II. Teaching with Documents.

ERIC Educational Resources Information Center

National Archives and Records Administration, Washington, DC.

Guns, tanks, and bombs were the principal weapons of World War II, but there were other, more subtle forms of warfare. Words, posters, and films waged a constant battle for the hearts and minds of the U.S. citizenry as military weapons engaged the enemy. Persuading the U.S. public became a wartime industry, almost as important as the manufacturing…

Molecular Subtypes of Glioblastoma Are Relevant to Lower Grade Glioma

PubMed Central

Sloan, Andrew E.; Chen, Yanwen; Brat, Daniel J.; O’Neill, Brian Patrick; de Groot, John; Yust-Katz, Shlomit; Yung, Wai-Kwan Alfred; Cohen, Mark L.; Aldape, Kenneth D.; Rosenfeld, Steven; Verhaak, Roeland G. W.; Barnholtz-Sloan, Jill S.

2014-01-01

Background Gliomas are the most common primary malignant brain tumors in adults with great heterogeneity in histopathology and clinical course. The intent was to evaluate the relevance of known glioblastoma (GBM) expression and methylation based subtypes to grade II and III gliomas (ie. lower grade gliomas). Methods Gene expression array, single nucleotide polymorphism (SNP) array and clinical data were obtained for 228 GBMs and 176 grade II/II gliomas (GII/III) from the publically available Rembrandt dataset. Two additional datasets with IDH1 mutation status were utilized as validation datasets (one publicly available dataset and one newly generated dataset from MD Anderson). Unsupervised clustering was performed and compared to gene expression subtypes assigned using the Verhaak et al 840-gene classifier. The glioma-CpG Island Methylator Phenotype (G-CIMP) was assigned using prediction models by Fine et al. Results Unsupervised clustering by gene expression aligned with the Verhaak 840-gene subtype group assignments. GII/IIIs were preferentially assigned to the proneural subtype with IDH1 mutation and G-CIMP. GBMs were evenly distributed among the four subtypes. Proneural, IDH1 mutant, G-CIMP GII/III s had significantly better survival than other molecular subtypes. Only 6% of GBMs were proneural and had either IDH1 mutation or G-CIMP but these tumors had significantly better survival than other GBMs. Copy number changes in chromosomes 1p and 19q were associated with GII/IIIs, while these changes in CDKN2A, PTEN and EGFR were more commonly associated with GBMs. Conclusions GBM gene-expression and methylation based subtypes are relevant for GII/III s and associate with overall survival differences. A better understanding of the association between these subtypes and GII/IIIs could further knowledge regarding prognosis and mechanisms of glioma progression. PMID:24614622

Novel fabrication method of microchannel plates

NASA Astrophysics Data System (ADS)

Yi, Whikun; Jeong, Taewon; Jin, Sunghwan; Yu, SeGi; Lee, Jeonghee; Kim, J. M.

2000-11-01

We have developed a novel microchannel plate (MCP) by introducing new materials and process technologies. The key features of our MCP are summarized as follows: (i) bulk alumina as a substrate, (ii) the channel location defined by a programmed-hole puncher, (iii) thin film deposition by electroless plating and/or sol-gel process, and (iv) an easy fabrication process suitable for mass production and a large-sized MCP. The characteristics of the resulting MCP have been evaluated with a high input current source such as a continuous electron beam from an electron gun and Spindt-type field emitters to obtain information on electron multiplication. In the case of a 0.28 μA incident beam, the output current enhances ˜170 times, which is equal to 1% of the total bias current of the MCP at a given bias voltage of 2600 V. When we insert a MCP between the cathode and the anode of a field emission display panel, the brightness of luminescent light increases 3-4 times by multiplying the emitted electrons through pore arrays of a MCP.

Secondary emission electron gun using external primaries

DOEpatents

Srinivasan-Rao, Triveni [Shoreham, NY; Ben-Zvi, Ilan [Setauket, NY

2009-10-13

An electron gun for generating an electron beam is provided, which includes a secondary emitter. The secondary emitter includes a non-contaminating negative-electron-affinity (NEA) material and emitting surface. The gun includes an accelerating region which accelerates the secondaries from the emitting surface. The secondaries are emitted in response to a primary beam generated external to the accelerating region. The accelerating region may include a superconducting radio frequency (RF) cavity, and the gun may be operated in a continuous wave (CW) mode. The secondary emitter includes hydrogenated diamond. A uniform electrically conductive layer is superposed on the emitter to replenish the extracted current, preventing charging of the emitter. An encapsulated secondary emission enhanced cathode device, useful in a superconducting RF cavity, includes a housing for maintaining vacuum, a cathode, e.g., a photocathode, and the non-contaminating NEA secondary emitter with the uniform electrically conductive layer superposed thereon.

Secondary emission electron gun using external primaries

DOEpatents

Srinivasan-Rao, Triveni [Shoreham, NY; Ben-Zvi, Ilan [Setauket, NY; Kewisch, Jorg [Wading River, NY; Chang, Xiangyun [Middle Island, NY

2007-06-05

An electron gun for generating an electron beam is provided, which includes a secondary emitter. The secondary emitter includes a non-contaminating negative-electron-affinity (NEA) material and emitting surface. The gun includes an accelerating region which accelerates the secondaries from the emitting surface. The secondaries are emitted in response to a primary beam generated external to the accelerating region. The accelerating region may include a superconducting radio frequency (RF) cavity, and the gun may be operated in a continuous wave (CW) mode. The secondary emitter includes hydrogenated diamond. A uniform electrically conductive layer is superposed on the emitter to replenish the extracted current, preventing charging of the emitter. An encapsulated secondary emission enhanced cathode device, useful in a superconducting RF cavity, includes a housing for maintaining vacuum, a cathode, e.g., a photocathode, and the non-contaminating NEA secondary emitter with the uniform electrically conductive layer superposed thereon.

Effects of policies designed to keep firearms from high-risk individuals.

PubMed

Webster, Daniel W; Wintemute, Garen J

2015-03-18

This article summarizes and critiques available evidence from studies published between 1999 and August 2014 on the effects of policies designed to keep firearms from high-risk individuals in the United States. Some prohibitions for high-risk individuals (e.g., those under domestic violence restraining orders, violent misdemeanants) and procedures for checking for more types of prohibiting conditions are associated with lower rates of violence. Certain laws intended to prevent prohibited persons from accessing firearms-rigorous permit-to-purchase, comprehensive background checks, strong regulation and oversight of gun dealers, and requiring gun owners to promptly report lost or stolen firearms-are negatively associated with the diversion of guns to criminals. Future research is needed to examine whether these laws curtail nonlethal gun violence and whether the effects of expanding prohibiting conditions for firearm possession are modified by the presence of policies to prevent diversion.

Evaluating Metabolite-Related DNA Oxidation and Adduct Damage from Aryl Amines Using a Microfluidic ECL Array.

PubMed

Bist, Itti; Bhakta, Snehasis; Jiang, Di; Keyes, Tia E; Martin, Aaron; Forster, Robert J; Rusling, James F

2017-11-21

Damage to DNA from the metabolites of drugs and pollutants constitutes a major human toxicity pathway known as genotoxicity. Metabolites can react with metal ions and NADPH to oxidize DNA or participate in S N 2 reactions to form covalently linked adducts with DNA bases. Guanines are the main DNA oxidation sites, and 8-oxo-7,8-dihydro-2-deoxyguanosine (8-oxodG) is the initial product. Here we describe a novel electrochemiluminescent (ECL) microwell array that produces metabolites from test compounds and measures relative rates of DNA oxidation and DNA adduct damage. In this new array, films of DNA, metabolic enzymes, and an ECL metallopolymer or complex assembled in microwells on a pyrolytic graphite wafer are housed in dual microfluidic chambers. As reactant solution passes over the wells, metabolites form and can react with DNA in the films to form DNA adducts. These adducts are detected by ECL from a RuPVP polymer that uses DNA as a coreactant. Aryl amines also combine with Cu 2+ and NADPH to form reactive oxygen species (ROS) that oxidize DNA. The resulting 8-oxodG was detected selectively by ECL-generating bis(2,2'-bipyridine)-(4-(1,10-phenanthrolin-6-yl)-benzoic acid)Os(II). DNA/enzyme films on magnetic beads were oxidized similarly, and 8-oxodG determined by LC/MS/MS enabled array standardization. The array limit of detection for oxidation was 720 8-oxodG per 10 6 nucleobases. For a series of aryl amines, metabolite-generated DNA oxidation and adduct formation turnover rates from the array correlated very well with rodent 1/TD 50 and Comet assay results.

2. Northwest circular bastion, seen from edge of southwest circular ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. Northwest circular bastion, seen from edge of southwest circular bastion wall. Metal roof beams extend up to form peak. World War II gun installation at right. - Fort Hamilton, Northwest Circular Bastion, Rose Island, Newport, Newport County, RI

DISGUISED IN AN OCEANIC CAMOUFLAGE PAINT SCHEME, EVERGREEN MAKES HER ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

DISGUISED IN AN OCEANIC CAMOUFLAGE PAINT SCHEME, EVERGREEN MAKES HER WAY THROUGH THE NORTH ATLANTIC DURING WORLD WAR II. HER 3" GUN IS VISIBLE BEHIND THE STACK - U.S. Coast Guard Cutter EVERGREEN, New London, New London County, CT

Effects of Exposure to the Sound from Seismic Airguns on Pallid Sturgeon and Paddlefish

PubMed Central

Gross, Jackson A.; Carlson, Thomas J.; Skalski, John; Young, John V.; Hawkins, Anthony D.; Zeddies, David

2016-01-01

This study examined the effects of exposure to a single acoustic pulse from a seismic airgun array on caged endangered pallid sturgeon (Scaphirhynchus albus) and on paddlefish (Polyodon spathula) in Lake Sakakawea (North Dakota, USA). The experiment was designed to detect the onset of physiological responses including minor to mortal injuries. Experimental fish were held in cages as close as 1 to 3 m from the guns where peak negative sound pressure levels (Peak- SPL) reached 231 dB re 1 μPa (205 dB re 1 μPa2·s sound exposure level [SEL]). Additional cages were placed at greater distances in an attempt to develop a dose-response relationship. Treatment and control fish were then monitored for seven days, euthanized, and necropsied to determine injuries. Necropsy results indicated that the probability of delayed mortality associated with pulse pressure following the seven day monitoring period was the same for exposed and control fish of both species. Exposure to a single pulse from a small air gun array (10,160 cm3) was not lethal for pallid sturgeon and paddlefish. However, the risks from exposure to multiple sounds and to sound exposure levels that exceed those reported here remain to be examined. PMID:27505029

Effects of Exposure to the Sound from Seismic Airguns on Pallid Sturgeon and Paddlefish.

PubMed

Popper, Arthur N; Gross, Jackson A; Carlson, Thomas J; Skalski, John; Young, John V; Hawkins, Anthony D; Zeddies, David

2016-01-01

This study examined the effects of exposure to a single acoustic pulse from a seismic airgun array on caged endangered pallid sturgeon (Scaphirhynchus albus) and on paddlefish (Polyodon spathula) in Lake Sakakawea (North Dakota, USA). The experiment was designed to detect the onset of physiological responses including minor to mortal injuries. Experimental fish were held in cages as close as 1 to 3 m from the guns where peak negative sound pressure levels (Peak- SPL) reached 231 dB re 1 μPa (205 dB re 1 μPa2·s sound exposure level [SEL]). Additional cages were placed at greater distances in an attempt to develop a dose-response relationship. Treatment and control fish were then monitored for seven days, euthanized, and necropsied to determine injuries. Necropsy results indicated that the probability of delayed mortality associated with pulse pressure following the seven day monitoring period was the same for exposed and control fish of both species. Exposure to a single pulse from a small air gun array (10,160 cm3) was not lethal for pallid sturgeon and paddlefish. However, the risks from exposure to multiple sounds and to sound exposure levels that exceed those reported here remain to be examined.

Gun Propellant Residues Dispersed from Static Artillery Firings of LG1 Mark 2 and C3 105-mm Howitzers

DTIC Science & Technology

2008-10-01

nitroglycerine (NG). In this study, aluminium witness plates were placed in front of the muzzle of the gun to collect residues propelled in the environment...témoins en aluminium ont été placées en face de la bouche du canon pour récolter les résidus de tirs propulsés dans l’environnement. Les plaques ont été...the Mark II and C3 105-mm howitzers, during an artillery exercise performed from May 9 to May 12, 2005 at CFB Gagetown in New-Brunswick. Aluminium

High-energy photon spectra from a coaxial gas-puff experiment

NASA Astrophysics Data System (ADS)

Warren, S. W. R.; Degnan, J. H.; Beason, C. W.; Price, D. W.; Snell, M. P.

1987-04-01

An array of plastic scintillator/photomultiplier detectors was used to determine the high-energy (h x nu greater than 35 keV) photon spectra of a 130-kJ, 60-kV gas-injected coaxial-gun experiment. The detector array used six different filter-material/thickness combinations. High-energy photon signals were readily observed. The spectra were determined by deconvolution. The spectra have three characteristic components: radiative emission from high-Z impurities in the plasma, beam-target excited line emission, and thick-target bremsstrahlung from an electron beam generated in the plasma column. The electron beam consistent with the thick-target bremsstrahlung assumption was of the order of 100 A above 10 keV.

24. Photocopy of photograph (original print located in LBNL Photo ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

24. Photocopy of photograph (original print located in LBNL Photo Lab Collection). George Kagawa, Photographer. B-51. November 6, 1961. BEV-2497 ION GUN II, EMERY ZAJEC - University of California Radiation Laboratory, Bevatron, 1 Cyclotron Road, Berkeley, Alameda County, CA

ARCHIE, FLAK, AAA, AND SAM A Short Operational History of Ground-Based Air Defense

DTIC Science & Technology

1988-12-01

81 44 Nike Ajax...83 45 Nike Hercules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84 46 Hawk...German Artillery of World War II (London: Arms and Armour , 1975), 162, 167 ; R. A. Devereux, "German Experience with Antiaircraft Artillery Guns in WWII

EXCEDE Support Studies.

DTIC Science & Technology

1981-09-15

OW #gV Or aftoa inmbt) EXCEDE, electron beam, thermosphere, aurora, LWIR , NO + air afterglow, hypersonic wake AG? (C mw~m M ~re 1o AM C@ " Cow lame...REGION 5 EXCEDE SPECTRAL: LWIR SIGNATURE ANALYSIS 28 HYPERSONIC WAKE EFFECTS ON EXCEDE: SPECTRAL LOW ALTITUDE DATA INTERPRETATION 47 LONG LIVED BEAM...physical displacement of gun 4 from the two CVFs, however, meant that the very nonuniform dosing in the immediate vicinity of the electron gun is not the

Advanced Technology for Naval Gun Tubes

DTIC Science & Technology

1971-02-01

maraging steel of the same strength level. Steel G. Precipitation -hardened stainless steels There are several different grades of precipitation -hardened...to a yield strength of 180,000 psi would be higher than about 20 ft. -lbs. The corrosion resistance of the precipitation -hardened stainless steels ...be over 25 ft.-lbs. at -40oF. 17 Maraging and stainless steels , which may have some future application for gun tubes, should also be considered in

Improved DC Gun and Insulator Assembly

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

Neubauer, Michael

Many user facilities such as synchrotron radiation light sources and free electron lasers rely on DC high voltage photoguns with internal field gradients as high as 10 to 15 MV/m. These high gradients often lead to field emission which poses serious problems for the photocathode used to generate the electron beam and the ceramic insulators used to bias the photocathode at high voltage. Ceramic insulators are difficult to manufacture, require long commissioning times, and have poor reliability, in part because energetic electrons bury themselves in the ceramic causing a buildup of charge and eventual puncture, and also because large diametermore » ceramics are difficult to braze reliably. The lifetimes of photo cathodes inside high current DC guns exhibiting field emission are limited to less than a hundred hours. Reducing the surface gradients on the metals reduces the field emission, which serves to maintain the required ultrahigh vacuum condition. A novel gun design with gradients around 5 MV/m and operating at 350 kV, a major improvement over existing designs, was proposed that allows for the in-situ replacement of photo cathodes in axially symmetric designs using inverted ceramics. In this project, the existing JLAB CEBAF asymmetric gun design with an inverted ceramic support was modeled and the beam dynamics characterized. An improved structure was designed that reduces the surface gradients and improves the beam optics. To minimize the surface gradients, a number of electrostatic gun designs were studied to determine the optimum configuration of the critical electrodes within the gun structure. Coating experiments were carried out to create a charge dissipative coating for cylindrical ceramics. The phase II proposal, which was not granted, included the design and fabrication of an axially symmetric DC Gun with an inverted ceramic that would operate with less than 5 MV/m at 350 kV and would be designed with an in-situ replaceable photo-cathode.« less

Gas and gas hydrate distribution around seafloor seeps in Mississippi Canyon, Northern Gulf of Mexico, using multi-resolution seismic imagery

USGS Publications Warehouse

Wood, W.T.; Hart, P.E.; Hutchinson, D.R.; Dutta, N.; Snyder, F.; Coffin, R.B.; Gettrust, J.F.

2008-01-01

To determine the impact of seeps and focused flow on the occurrence of shallow gas hydrates, several seafloor mounds in the Atwater Valley lease area of the Gulf of Mexico were surveyed with a wide range of seismic frequencies. Seismic data were acquired with a deep-towed, Helmholz resonator source (220-820 Hz); a high-resolution, Generator-Injector air-gun (30-300 Hz); and an industrial air-gun array (10-130 Hz). Each showed a significantly different response in this weakly reflective, highly faulted area. Seismic modeling and observations of reversed-polarity reflections and small scale diffractions are consistent with a model of methane transport dominated regionally by diffusion but punctuated by intense upward advection responsible for the bathymetric mounds, as well as likely advection along pervasive filamentous fractures away from the mounds.

Controllable 3D architectures of aligned carbon nanotube arrays by multi-step processes

NASA Astrophysics Data System (ADS)

Huang, Shaoming

2003-06-01

An effective way to fabricate large area three-dimensional (3D) aligned CNTs pattern based on pyrolysis of iron(II) phthalocyanine (FePc) by two-step processes is reported. The controllable generation of different lengths and selective growth of the aligned CNT arrays on metal-patterned (e.g., Ag and Au) substrate are the bases for generating such 3D aligned CNTs architectures. By controlling experimental conditions 3D aligned CNT arrays with different lengths/densities and morphologies/structures as well as multi-layered architectures can be fabricated in large scale by multi-step pyrolysis of FePc. These 3D architectures could have interesting properties and be applied for developing novel nanotube-based devices.

Controlled simulation of optical turbulence in a temperature gradient air chamber

NASA Astrophysics Data System (ADS)

Toselli, Italo; Wang, Fei; Korotkova, Olga

2016-05-01

Atmospheric turbulence simulator is built and characterized for in-lab optical wave propagation with controlled strength of the refractive-index fluctuations. The temperature gradients are generated by a sequence of heat guns with controlled individual strengths. The temperature structure functions are measured in two directions transverse to propagation path with the help of a thermocouple array and used for evaluation of the corresponding refractive-index structure functions of optical turbulence.

Ensuring Operational Readiness: Private Military Contractor Support for the United States Air Force

DTIC Science & Technology

2017-03-15

range, supersonic, low altitude terrain following bomber that could evade Soviet detection. It is now loaded with conventional bombs and flown hundreds... bombs that commercially available single engine propeller planes can employ. The Airmen who perform this endeavor are America’s finest. They...array of weapons, to include laser, electro optical, and infrared guided missiles, laser and GPS guided bombs , 2.75” rockets, and a 20mm Gatling gun

Advance in exploring the subsurface temporal evolution with Air-gun artificial source of Fujian, China

NASA Astrophysics Data System (ADS)

Yandan, H.; Jun, L.; Jin, X.; Tianyun, W.

2017-12-01

Geological disasters occur with the stress changes of subsurface medium. Since the stress changes slowly in the deep earth where only seismic wave can reach, monitoring the changes with repeatable seismic sources, ambient seismic noise and artificial sources has become a hot topic in seismology. The Fujian Earthquake Agency successfully constructed the Air-gun artificial source system and carried out over 6000 shots in six reservoirs. The correlation coefficient of signals can reach up to 0.99. Besides an excellent source, high recognition ability of seismic wave changes is required. It is common to use time delay estimation method based on cross-correlation to recognize the velocity changes. We investigate the accuracy of time delay detection of Air-gun source signals. Suppose that the medium does not change in a short time, we changed the explosion conditions of the air-gun array and recognized the subtle changes of signals by the time delay estimation method: (1) we changed the excitation depth from 8m to 30m, and found that the arriving time of bubble pulses advanced nearly 90ms. The results are quite consistent with the records of the OBS on the bottom of reservoir; (2) we changed the firing pressure from 800Psi to 2000Psi, and found that the bubble pulses were quite different but now we don't have any suitable numerical model to fit the changes; (3) we changed the excitation position of the air-gun, and divided the changed distance between the Air-gun and the near-shore seismograph by the corresponding changed travelling time. Then we got a velocity of 1.5km/s, which equals to the sound speed in water; (4) we controlled the microsecond of explosion moment from 0ms to 9ms, and counted the time delays of waveforms. Results are quite consistent with the theoretical value; (5) we changed the explosion mode, and quantitatively recognized the 0.1ms changes of the signal travel time. Our experiments show that the method is of high precision that can recognize the microsecond changes of the waves. Next step, we are planning to establish a fixed Air-gun signal transmitting station in Fujian, China.

49 CFR 173.62 - Specific packaging requirements for explosives.

Code of Federal Regulations, 2011 CFR

2011-10-01

... article or material carried in the vehicle; and (ii) The assembled gun packed on the vehicle may not... HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS... kg in small packages as specified by the Associate Administrator for Hazardous Materials Safety 110(a...

49 CFR 173.62 - Specific packaging requirements for explosives.

Code of Federal Regulations, 2012 CFR

2012-10-01

... article or material carried in the vehicle; and (ii) The assembled gun packed on the vehicle may not... HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS... packages as specified by the Associate Administrator for Hazardous Materials Safety 110(a) Bags Bags Drums...

Method: low-cost delivery of the cotton leaf crumple virus-induced gene silencing system

PubMed Central

2012-01-01

Background We previously developed a virus-induced gene silencing (VIGS) vector for cotton from the bipartite geminivirusCotton leaf crumple virus (CLCrV). The original CLCrV VIGS vector was designed for biolistic delivery by a gene gun. This prerequisite limited the use of the system to labs with access to biolistic equipment. Here we describe the adaptation of this system for delivery by Agrobacterium (Agrobacterium tumefaciens). We also describe the construction of two low-cost particle inflow guns. Results The biolistic CLCrV vector was transferred into two Agrobacterium binary plasmids. Agroinoculation of the binary plasmids into cotton resulted in silencing and GFP expression comparable to the biolistic vector. Two homemade low-cost gene guns were used to successfully inoculate cotton (G. hirsutum) and N. benthamiana with either the CLCrV VIGS vector or the Tomato golden mosaic virus (TGMV) VIGS vector respectively. Conclusions These innovations extend the versatility of CLCrV-based VIGS for analyzing gene function in cotton. The two low-cost gene guns make VIGS experiments affordable for both research and teaching labs by providing a working alternative to expensive commercial gene guns. PMID:22853641

International Space Station (ISS)

NASA Image and Video Library

2006-09-13

These six STS 117 astronauts, assigned to launch aboard the Space Shuttle Atlantis, are (from the left) astronauts James F. Reilly II, Steven R. Swanson, mission specialists; Frederick W. (Rick) Sturckow, commander; Lee J. Archambault, pilot; and Patrick G. Forrester and John D. (Danny) Olivas, mission specialists. The crewmembers are attired in training versions of their shuttle launch and entry suits. Mission objectives include the addition of the second and third starboard truss segments (S3/S4) with Photovoltaic Radiator (PVR), the deployed third set of solar arrays. The P6 starboard solar array wing and one radiator are to be retracted.

Organ models in wound ballistics: experimental study.

PubMed

Ozer, Mustafa Tahir; Oğünç, Gökhan; Eryilmaz, Mehmet; Yiğit, Taner; Menteş, Mustafa Oner; Dakak, Mehmet; Uzar, Ali Ihsan; Oner, Köksal

2007-01-01

Effects of various types and diameters of guns and related treatment principles are different. Our study was performed to experimentally demonstrate the effects of different gunshots in body tissues. 9x19 mm hand-gun and 7.62x51 mm G-3 infantry rifle were used in the study. Injury models were created through hand-gun and rifle shootings at isolated soft tissue, lower extremity, liver and intestine tissue simulants made of ballistic candle. High-speed cameras were used to capture 1000 frames per second. Images were examined and wound mechanisms were evaluated. It was observed that the colon content distributed more within the surrounding tissues by the rifle shootings comparing with hand-gun shootings and could be an infection source due to the large size of the cavity in the colon. Especially when the bullets hitting the bone were investigated, it was seen that much more tissue injury occurs with high speed bullets due to bullet deformation and fragmentation. However, no significant difference was found between the effect of hand-gun and rifle bullets passing through the extremity without hitting the bone. To know the type of the gun that caused the injury and its characteristics will allow to estimate severity and size of the injury before the treatment and to focus on different alternatives of treatment. Therefore, use of appropriate models is required in experimental studies.

Shooting rampages, mental health, and the sensationalization of violence.

PubMed

Faria, Miguel A

2013-01-01

Gun violence and, most recently, senseless shooting rampages continue to be sensitive and emotional points of debate in the American media and the political establishment. The United Nations is already set to commence discussing and approving its Small Arms Treaty in March 2013. And following the Newtown, Connecticut tragedy in the United States this past December, American legislators are working frantically to pass more stringent gun control laws in the U.S. Congress. The American media and proponents of gun control assert that the problem lies in the "easy availability of guns" and "too many guns" in the hand of the public. Second Amendment and gun rights advocates, on the other hand, believe the problem lies elsewhere, including a permissive criminal justice system that panders to criminals; the failure of public education; the fostering of a culture of dependence, violence, and alienation engendered by the welfare state; and the increased secularization of society with children and adolescents growing up devoid of moral guidance. I cannot disagree with the latter view, but I believe there are additional, contributing, and more proximate causes - e.g., failures of the mental health system and the role of the media and popular culture in the sensationalization of violence - that also need to be specifically pointed out and discussed in the medical literature, as I have set out to do in this review article.

Modified M20 Beam Position Monitor Testing

NASA Astrophysics Data System (ADS)

Koros, Jessica; Musson, John

2017-09-01

Beam position monitors (BPMs) are used to measure lateral beam position. Two pairs of modified wire BPMs are being evaluated for installation into the injector at Jefferson Lab (JLab). The BPMs were coated with a Non-Evaporable Getter (NEG) to aid in pumping at the electron gun, as an ultra-high vacuum is required to protect the gun and to avoid scattering the beam. Beam in the injector has a large diameter, allowing extraction of second moments to give information about beam profile and emittance. The purpose of this project is to determine the effects of NEG coating on the BPMs and to calculate second moments from beam models on the Goubau Line (G-Line). Using the G-Line, scans of the BPMs were taken before and after NEG coating. Each scan produced an electrical field map, which characterizes properties of the BPM, including scale factors and coupling. Second moments were calculated using superposition of previous scan data, and verification of this method was attempted using several beam models. Results show the BPMs responded well to NEG and that measurement of second moments is possible. Once the BPMs are installed, they will enhance gun vacuum and enable monitoring of shape and trajectory of the beam as it exits the electron gun to ensure quality beam for experiments. This work is made possible through support from NSF award 1659177 to Old Dominion University.

Biomechanics of head injury in olympic taekwondo and boxing.

PubMed

Fife, G P; O'Sullivan, D; Pieter, W

2013-12-01

The purpose was to examine differences between taekwondo kicks and boxing punches in resultant linear head acceleration (RLA), head injury criterion (HIC15), peak head velocity, and peak foot and fist velocities. Data from two existing publications on boxing punches and taekwondo kicks were compared. For taekwondo head impacts a Hybrid II Crash Dummy (Hybrid II) head was instrumented with a tri-axial accelerometer mounted inside the Hybrid II head. The Hybrid II was fixed to a height-adjustable frame and fitted with a protective taekwondo helmet. For boxing testing, a Hybrid III Crash Dummy head was instrumented with an array of tri-axial accelerometers mounted at the head centre of gravity. Differences in RLA between the roundhouse kick (130.11±51.67 g) and hook punch (71.23±32.19 g, d = 1.39) and in HIC15 (clench axe kick: 162.63±104.10; uppercut: 24.10±12.54, d = 2.29) were observed. Taekwondo kicks demonstrated significantly larger magnitudes than boxing punches for both RLA and HIC.

Facile fabrication of Cu(II)-porphyrin MOF thin films from tetrakis(4-carboxyphenyl)porphyrin and Cu(OH)2 nanoneedle array

NASA Astrophysics Data System (ADS)

La, Duong Duc; Thi, Hoai Phuong Nguyen; Kim, Yong Shin; Rananaware, Anushri; Bhosale, Sheshanath V.

2017-12-01

Herein, we report a facile synthetic protocol to grow thin films of Cu(II) tetrakis(4-carboxyphenyl)porphyrin (CuTCPP) metal-organic frameworks (MOF) from a tetrakis(4-carboxyphenyl)porphyrin (H2TCPP) solution and the copper hydroxide (Cu(OH)2) nanoneedle array formed on a Cu substrate at room temperature. The formations of Cu-centered TCPP ligands and crystalline platelet-like Cu MOFs were successfully probed by SEM, XRD, FTIR, UV-vis and XPS. The formation process from Cu(OH)2 was monitored by using SEM images obtained at different reaction times during the first 24 h, thus suggesting the reaction pathway of Cu(OH)2 dissolution followed by the reprecipitation of CuTCPP MOFs at a near surface. In addition, the CuTCPP MOFs exhibited a high specific surface area of 408 m2/g.

A Physics Exploratory Experiment on Plasma Liner Formation

NASA Technical Reports Server (NTRS)

Thio, Y. C. Francis; Knapp, Charles E.; Kirkpatrick, Ronald C.; Siemon, Richard E.; Turchi, Peter

2002-01-01

Momentum flux for imploding a target plasma in magnetized target fusion (MTF) may be delivered by an array of plasma guns launching plasma jets that would merge to form an imploding plasma shell (liner). In this paper, we examine what would be a worthwhile experiment to do in order to explore the dynamics of merging plasma jets to form a plasma liner as a first step in establishing an experimental database for plasma-jets driven magnetized target fusion (PJETS-MTF). Using past experience in fusion energy research as a model, we envisage a four-phase program to advance the art of PJETS-MTF to fusion breakeven Q is approximately 1). The experiment (PLX (Plasma Liner Physics Exploratory Experiment)) described in this paper serves as Phase I of this four-phase program. The logic underlying the selection of the experimental parameters is presented. The experiment consists of using twelve plasma guns arranged in a circle, launching plasma jets towards the center of a vacuum chamber. The velocity of the plasma jets chosen is 200 km/s, and each jet is to carry a mass of 0.2 mg - 0.4 mg. A candidate plasma accelerator for launching these jets consists of a coaxial plasma gun of the Marshall type.

A contoured gap coaxial plasma gun with injected plasma armature.

PubMed

Witherspoon, F Douglas; Case, Andrew; Messer, Sarah J; Bomgardner, Richard; Phillips, Michael W; Brockington, Samuel; Elton, Raymond

2009-08-01

A new coaxial plasma gun is described. The long term objective is to accelerate 100-200 microg of plasma with density above 10(17) cm(-3) to greater than 200 km/s with a Mach number above 10. Such high velocity dense plasma jets have a number of potential fusion applications, including plasma refueling, magnetized target fusion, injection of angular momentum into centrifugally confined mirrors, high energy density plasmas, and others. The approach uses symmetric injection of high density plasma into a coaxial electromagnetic accelerator having an annular gap geometry tailored to prevent formation of the blow-by instability. The injected plasma is generated by numerous (currently 32) radially oriented capillary discharges arranged uniformly around the circumference of the angled annular injection region of the accelerator. Magnetohydrodynamic modeling identified electrode profiles that can achieve the desired plasma jet parameters. The experimental hardware is described along with initial experimental results in which approximately 200 microg has been accelerated to 100 km/s in a half-scale prototype gun. Initial observations of 64 merging injector jets in a planar cylindrical testing array are presented. Density and velocity are presently limited by available peak current and injection sources. Steps to increase both the drive current and the injected plasma mass are described for next generation experiments.

Development of Field-Reversed Configuration Plasma Gun Formation Techniques for Magnetized Target Fusion

NASA Astrophysics Data System (ADS)

Lynn, Alan; Gilmore, Mark; Wynkoop, Tyler; Intrator, Thomas; Weber, Thomas

2012-10-01

Magnetized Target Fusion (MTF) is an innovative approach for a relatively fast and cheap path to the production of fusion energy that utilizes magnetic confinement to assist in the compression of a hot plasma to thermonuclear conditions by an external driver. Los Alamos National Laboratory (LANL) is currently pursing demonstration of the MTF concept via compression of an FRC (field-reversed configuration) plasma by a metal liner z-pinch in conjunction with the Air Force Research Laboratory in Albuquerque, NM. A key physics issue for the FRC as an MTF target lies in the initial pre-ionization (PI) stage. The PI formation process determines the amount of magnetic flux that can be trapped to form the FRC. This trapped flux plays an important role in the FRC's final equilibrium, transport, and stability properties. It also provides the route to greatest potential gains in FRC lifetime, which is essential to provide enough time to translate and compress the FRC effectively. In conjunction with LANL we plan to test and characterize a new system to improve the initial PI plasma formation. This system will use an array of plasma guns to form the initial plasma. Initial characterization of the plasma gun behavior will be presented.

BEAM DYNAMICS STUDIES OF A HIGH-REPETITION RATE LINAC-DRIVER FOR A 4TH GENERATION LIGHT SOURCE

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

Ventturini, M.; Corlett, J.; Emma, P.

2012-05-18

We present recent progress toward the design of a super-conducting linac driver for a high-repetition rate FEL-based soft x-ray light source. The machine is designed to accept beams generated by the APEX photo-cathode gun operating with MHz-range repetition rate and deliver them to an array of SASE and seeded FEL beamlines. We review the current baseline design and report results of beam dynamics studies.

Getting Real about Resiliency: Two Approaches

DTIC Science & Technology

2013-02-14

Union and Confederate armies, and the Greatest Generation that liberated Europe in World War II retuned to home and hearth once the guns fell silent...alcohol abuse in our returning veterans.19 In addition, a statistic often overlooked is the rise in divorce rates. Many return to hearth and home with

Proceedings of the American Journalism Historians' Association Conference (Roanoke, Virginia, October 6-8, 1994). Part II.

ERIC Educational Resources Information Center

American Journalism Historians' Association.

The second part of the proceedings of this conference of journalism historians contains the following 21 papers: "The First Information Revolution" (Irving Fang); "The 'Andromeda Strain' Phenomenon: Mutating Systems and International Communication Policy" (Eliza Tanner); "Guns or Butter?: Black Press Editorial Policy…

40 CFR 745.85 - Work practice standards.

Code of Federal Regulations, 2010 CFR

2010-07-01

... CONTROL ACT LEAD-BASED PAINT POISONING PREVENTION IN CERTAIN RESIDENTIAL STRUCTURES Residential Property...-flame burning or torching of lead-based paint is prohibited. (ii) The use of machines that remove lead...) Operating a heat gun on lead-based paint is permitted only at temperatures below 1100 degrees Fahrenheit. (4...

Analysis of Rail Gun Bore Residue

DTIC Science & Technology

1984-03-01

erosion effects and elemental analysis of refractory materials. C. A. L. Westerdahl , J. Pinto, G. L. Ferventino, D. N. Saherhavth...accelerator facility at Large Caliber Weapons Systems Laboratory Dover, New Jersey. ’ 16 REFERENCES 1. C.A.L. Westerdahl , J. Pinto, G. L. Ferrentino, D

Dynamics of Plasma Jets and Bubbles Launched into a Transverse Background Magnetic Field

NASA Astrophysics Data System (ADS)

Zhang, Yue

2017-10-01

A coaxial magnetized plasma gun has been utilized to launch both plasma jets (open B-field) and plasma bubbles (closed B-field) into a transverse background magnetic field in the HelCat (Helicon-Cathode) linear device at the University of New Mexico. These situations may have bearing on fusion plasmas (e.g. plasma injection for tokamak fueling, ELM pacing, or disruption mitigation) and astrophysical settings (e.g. astrophysical jet stability, coronal mass ejections, etc.). The magnetic Reynolds number of the gun plasma is 100 , so that magnetic advection dominates over magnetic diffusion. The gun plasma ram pressure, ρjetVjet2 >B02 / 2μ0 , the background magnetic pressure, so that the jet or bubble can easily penetrate the background B-field, B0. When the gun axial B-field is weak compared to the gun azimuthal field, a current-driven jet is formed with a global helical magnetic configuration. Applying the transverse background magnetic field, it is observed that the n = 1 kink mode is stabilized, while magnetic probe measurements show contrarily that the safety factor q(a) drops below unity. At the same time, a sheared axial jet velocity is measured. We conclude that the tension force arising from increasing curvature of the background magnetic field induces the measured sheared flow gradient above the theoretical kink-stabilization threshold, resulting in the emergent kink stabilization of the injected plasma jet. In the case of injected bubbles, spheromak-like plasma formation is verified. However, when the spheromak plasma propagates into the transverse background magnetic field, the typical self-closed global symmetry magnetic configuration does not hold any more. In the region where the bubble toroidal field opposed the background B-field, the magneto-Rayleigh-Taylor (MRT) instability has been observed. Details of the experiment setup, diagnostics, experimental results and theoretical analysis will be presented. Supported by the National Science Foundation under Grant No. AST-0613577 and the Army Research Office under Award No. W911NF1510480. This work performed in collaboration with D. Fisher, A. G. Lynn, M Gilmore, and S. C. Hsu.

Gridded thermionic gun and integral superconducting ballistic bunch compression cavity

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

Schultheiss, Thomas

Electron-Ion colliders such as the Medium energy Electron Ion Collider (MEIC) being developed by JLAB require high current electrons with low energy spread for electron cooling of the collider ring. Accelerator techniques for improving bunch charge, average current, emittance, and energy spread are required for Energy Recovery Linacs (ERLs) and Circulator Rings (CR) for next generation colliders for nuclear physics experiments. Example candidates include thermionic-cathode electron guns with RF accelerating structures. Thermionic cathodes are known to produce high currents and have excellent lifetime. The success of the IR and THz Free-Electron Laser (FEL) designed and installed by Advanced Energy Systemsmore » at the Fritz Haber Institute (FHI) of the Max Planck Society in Berlin [1,2] demonstrates that gridded thermionic cathodes and rf systems be considered for next generation collider technology. In Phase 1 Advanced Energy Systems (AES) developed and analyzed a design concept using a superconducting cavity pair and gridded thermionic cathode. Analysis included Beam Dynamics and thermal analysis to show that a design of this type is feasible. The latest design goals for the MEIC electron cooler were for electron bunches of 420 pC at a frequency of 952.6 MHz with a magnetic field on the cathode of 2kG. This field magnetizes the beam imparting angular momentum that provides for helical motion of the electrons in the cooling solenoid. The helical motion increases the interaction time and improves the cooling efficiency. A coil positioned around the cathode providing 2kG field was developed. Beam dynamics simulations were run to develop the particle dynamics near the cathode and grid. Lloyd Young added capability to Tstep to include space charge effects between two plates and include image charge effects from the grid. He also added new pepper-pot geometry capability to account for honeycomb grids. These additions were used to develop the beam dynamics for this gun. The general design is a modified ballistic compression cavity pair with two independently powered cells [3]. The first is a cathode cell that includes the thermionic cathode and grid to provide for beam bunching. The second is a full cell with independent phasing and field levels designed to minimize energy spread. The primary goal for Phase II is to manufacture a superconducting gun with a thermionic cathode and imbedded coil. The system developed here is applicable to many high current electron accelerators. The analysis and design constraints imposed by the magnetized cathode make the cathode system developed here more complicated and limited than one without the magnetized beam constraints. High power ERLs would benefit by a gun with the capabilities shown here, 400 mA or more of current. ERLs hold great promise for electron cooling experiments, advanced light sources and Free Electron Lasers. This high current electron injector is a technological advance that will place the requirements for an ERL capable of providing quality bunches needed for cooling within the MEIC circulator ring within reach. This injector would have application to future ERLs around the world.« less

Fish DNA vaccine against infectious hematopoietic necrosis virus: efficacy of various routes of immunization

USGS Publications Warehouse

Corbeil, Serge; Kurath, Gael; LaPatra, Scott E.

2000-01-01

The DNA vaccine, pIHNVw-G, contains the gene for the glycoprotein (G) of the rhabdovirus infectious hematopoietic necrosis virus (IHNV), a major pathogen of salmon and trout. The relative efficacy of various routes of immunisation with pIHNVw-G was evaluated using 1.8 g rainbow trout fry vaccinated via intramuscular injection, scarification of the skin, intraperitoneal injection, intrabuccal administration, cutaneous particle bombardment using a gene gun, or immersion in water containing DNA vaccine-coated beads. Twenty-seven days after vaccination neutralising antibody titres were determined, and 2 days later groups of vaccinated and control unvaccinated fish were subjected to an IHNV immersion challenge. Results of the virus challenge showed that the intramuscular injection and the gene gun immunisation induced protective immunity in fry, while intraperitoneal injection provided partial protection. Neutralising antibodies were not detected in sera of vaccinated fish regardless of the route of immunisation used, suggesting that cell mediated immunity may be at least partially responsible for the observed protection.

1984-1995 Evolution of Stratospheric Aerosol Size, Surface Area, and Volume Derived by Combining SAGE II and CLAES Extinction Measurements

NASA Technical Reports Server (NTRS)

Russell, Philip B.; Bauman, Jill J.

2000-01-01

This SAGE II Science Team task focuses on the development of a multi-wavelength, multi- sensor Look-Up-Table (LUT) algorithm for retrieving information about stratospheric aerosols from global satellite-based observations of particulate extinction. The LUT algorithm combines the 4-wavelength SAGE II extinction measurements (0.385 <= lambda <= 1.02 microns) with the 7.96 micron and 12.82 micron extinction measurements from the Cryogenic Limb Array Etalon Spectrometer (CLAES) instrument, thus increasing the information content available from either sensor alone. The algorithm uses the SAGE II/CLAES composite spectra in month-latitude-altitude bins to retrieve values and uncertainties of particle effective radius R(sub eff), surface area S, volume V and size distribution width sigma(sub g).

Changes in Attitudes toward Guns and Shootings following Implementation of the Baltimore Safe Streets Intervention.

PubMed

Milam, Adam J; Buggs, Shani A; Furr-Holden, C Debra M; Leaf, Philip J; Bradshaw, Catherine P; Webster, Daniel

2016-08-01

Among youth 15 to 24 years of age, homicide and nonfatal shootings are the leading causes of mortality and morbidity. Urban youth's attitudes and perceptions about the use of gun violence to resolve conflict present a major barrier to efforts to reduce gun homicides and nonfatal shootings. The current investigation extends the existing literature on attitudes toward guns and shootings among high-risk youth ages 18 to 24 by measuring perceived norms and viewpoints regarding gun violence in two analogous Baltimore City neighborhoods pre-implementation and 1-year post-implementation of the Safe Streets intervention (adapted from the CeaseFire/Cure Violence intervention). The Safe Streets intervention is designed for communities with high rates of gun violence and utilizes outreach workers to identify and build trusting relationships with youth ages 15 to 24 who are at greatest risk of being involved in gun violence. The outreach workers also position themselves in the community so that they can rapidly intervene in disputes that have the potential to lead to gun violence. Chi-squared tests and exploratory structural equation modeling (ESEM) were used to examine changes in attitudes toward gun violence 1 year after the implementation of the Safe Streets intervention. There was a statistically significantly improvement in 43 % of the attitudes assessed in the intervention community post-intervention compared to 13 % of the attitudes in the control community. There was a statistically significant improvement in the violent attitudes toward personal conflict resolution scale after implementation of the intervention in both the intervention (b = -0.522, p < 0.001) and control community (b = -0.204, p < 0.032). Exposure to the intervention (e.g., seeing stop shooting signs in your neighborhood) was also associated with the nonviolent attitudes toward conflict scale. Overall, the study found greater improvement in attitudes toward violence in the intervention community following the implementation of the Safe Streets program. These findings offer promising insights into future community violence prevention efforts.

MIT modular x-ray source systems for the study of plasma diagnostics

NASA Astrophysics Data System (ADS)

Coleman, J. W.; Wenzel, K. W.; Petrasso, R. D.; Lo, D. H.; Li, C. K.; Lierzer, J. R.; Wei, T.

1992-10-01

Two new x-ray source systems are now on line at our facility. Each provides an e-beam to 25 kV. Targets are interchangeable between machines, and four x-ray detectors may be used simultaneously with a target. The gridded e-gun of the RACEHORSE system gives a 0.5-1.0-cm pulsable spot on target. The nongridded e-gun of the SCORPION system provides a 0.3-mm or smaller dc microspot on target. RACEHORSE is being used to study and characterize type-II diamond photoconductors for use in diagnosing plasmas, while SCORPION is being used to develop a slitless spectrograph using photographic film. Source design details and some RACEHORSE results are presented.

WE-G-17A-08: Electron Gun Operation for in Line MRI-Linac Configurations: An Assessment of Beam Fidelity and Recovery Techniques for Different SIDs and Magnetic Field Strengths

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

Whelan, B; Keall, P; Ingham Institute, Liverpool, Aus

Purpose: To test the functionality of medical electron guns within the fringe field of a purpose built superconducting MRI magnet, and to test different recovery techniques for a variety of imaging field strengths and SIDs. Methods: Three different electron guns were simulated using Finite Element Modelling; a standard diode gun, a standard triode gun, and a novel diode gun designed to operate within parallel magnetic fields. The approximate working regime of each gun was established by assessing exit current in constant magnetic fields of varying strength and defining ‘working’ as less than 10% change in injection current. Next, the 1.0Tmore » MRI magnet was simulated within Comsol Multiphysics. The coil currents in this model were also scaled to produce field strengths of .5, 1, 1.5 and 3T. Various magnetic shield configurations were simulated, varying the SID from 800 to 1300mm. The average magnetic field within the gun region was assessed together with the distortion in the imaging volume - greater than 150uT distortion was considered unacceptable. Results: The conventional guns functioned in fields of less than 7.5mT. Conversely, the redesigned diode required fields greater than .1T to function correctly. Magnetic shielding was feasible for SIDS of greater than 1000mm for field strengths of .5T and 1T, and 1100mm for 1.5 and 3.0T. Beyond these limits shielding resulted in unacceptable MRI distortion. In contrast, the redesigned diode could perform acceptably for SIDs of less than 812, 896, 931, and 974mm for imaging strengths of 0.5, 1.0, 1.5, 3.0T. Conclusions: For in-line MRIlinac configurations where the electron gun is operating in low field regions, shielding is a straight forward option. However, as magnetic field strength increases and the SID is reduced, shielding results in too great a distortion in the MRI and redesigning the electron optics is the preferable solution. The authors would like to acknowledge funding from the National Health and Research Council (AUS), National Institute of Health (NIH), and Cancer Institute NSW.« less

Laser direct-write and crystallization of FeSi II micro-dot array for NIR light-emitting device application

NASA Astrophysics Data System (ADS)

Narazaki, Aiko; Kurosaki, Ryozo; Sato, Tadatake; Kawaguchi, Yoshizo; Niino, Hiroyuki

2007-02-01

We printed FeSi II micro-dot array on various kinds of substrates utilizing laser-induced forward transfer (LIFT). An amorphous FeSi II was deposited by sputtering on a transparent plate as a source film. A single KrF excimer laser pulse through a mask-projection system was imaged with a small micrometer-sized grid pattern onto a film/plate interface, resulting in the deposition of FeSi II micro-dot array on a facing substrate with a high number density of 10 4 mm -2. FeSi II in the β crystalline phase is a promising eco-friendly semiconductor because of NIR electroluminescence used for optical networking as well as abundant components reserve on the earth and non-toxicity. However, the β-FeSi II film fabrication generally required high-temperature multi-processes which hamper its integration and performance reproducibility. Using the LIFT of micro-dot array, we succeeded in room-temperature preparation of β-FeSi II. Micro-Raman spectroscopy confirmed the β crystalline phase in the micro-dots deposited on an unheated silica glass substrate. Thus, the LIFT is useful for integrating functional micro-dot array accompanied by the crystallization at lower temperatures.

Canine Distemper Virus DNA Vaccination Induces Humoral and Cellular Immunity and Protects against a Lethal Intracerebral Challenge

PubMed Central

Sixt, Nathalie; Cardoso, Alicia; Vallier, Agnès; Fayolle, Joël; Buckland, Robin; Wild, T. Fabian

1998-01-01

We have studied the immune responses to the two glycoproteins of the Morbillivirus canine distemper virus (CDV) after DNA vaccination of BALB/c mice. The plasmids coding for both CDV hemagglutinin (H) and fusion protein (F) induce high levels of antibodies which persist for more than 6 months. Intramuscular inoculation of the CDV DNA induces a predominantly immunoglobulin G2a (IgG2a) response (Th1 response), whereas gene gun immunization with CDV H evokes exclusively an IgG1 response (Th2 response). In contrast, the CDV F gene elicited a mixed, IgG1 and IgG2a response. Mice vaccinated (by gene gun) with either the CDV H or F DNA showed a class I-restricted cytotoxic lymphocyte response. Immunized mice challenged intracerebrally with a lethal dose of a neurovirulent strain of CDV were protected. However, approximately 30% of the mice vaccinated with the CDV F DNA became obese in the first 2 months following the challenge. This was not correlated with the serum antibody levels. PMID:9765383

Marshall Space Flight Center's Impact Testing Facility Capabilities

NASA Technical Reports Server (NTRS)

Finchum, Andy; Hubbs, Whitney; Evans, Steve

2008-01-01

Marshall Space Flight Center s (MSFC) Impact Testing Facility (ITF) serves as an important installation for space and missile related materials science research. The ITF was established and began its research in spacecraft debris shielding in the early 1960s, then played a major role in the International Space Station debris shield development. As NASA became more interested in launch debris and in-flight impact concerns, the ITF grew to include research in a variety of impact genres. Collaborative partnerships with the DoD led to a wider range of impact capabilities being relocated to MSFC as a result of the closure of Particle Impact Facilities in Santa Barbara, California. The Particle Impact Facility had a 30 year history in providing evaluations of aerospace materials and components during flights through rain, ice, and solid particle environments at subsonic through hypersonic velocities. The facility s unique capabilities were deemed a "National Asset" by the DoD. The ITF now has capabilities including environmental, ballistic, and hypervelocity impact testing utilizing an array of air, powder, and two-stage light gas guns to accommodate a variety of projectile and target types and sizes. Numerous upgrades including new instrumentation, triggering circuitry, high speed photography, and optimized sabot designs have been implemented. Other recent research has included rain drop demise characterization tests to obtain data for inclusion in on-going model development. The current and proposed ITF capabilities range from rain to micrometeoroids allowing the widest test parameter range possible for materials investigations in support of space, atmospheric, and ground environments. These test capabilities including hydrometeor, single/multi-particle, ballistic gas guns, exploding wire gun, and light gas guns combined with Smooth Particle Hydrodynamics Code (SPHC) simulations represent the widest range of impact test capabilities in the country.

Nail gun-induced open-globe injuries: a 10-year retrospective review.

PubMed

Kolomeyer, Anton M; Shah, Avni; Bauza, Alain M; Langer, Paul D; Zarbin, Marco A; Bhagat, Neelakshi

2014-02-01

To describe the characteristics of nail gun-related open-globe injuries. Retrospective series of all patients presenting with open globes secondary to nail gun injury from 2000 to 2010. Data were collected on demographics, setting of accident, presenting clinical examination findings, visual acuity, management, surgical procedures needed, and long-term outcomes. Forty-two patients (43 eyes; mean age, 31.6 years; 100% male; 79% Hispanic) suffered open-globe injury from nail gun accidents. Thirty-seven eyes (86%) sustained injury at work. One of 15 (6.7%) patients, on whom data were available, wore protective eyewear during the incident. Entrance wounds were classified into Zone I (n = 24 [56%]), Zone II (n = 12 [28%]), and Zone III (n = 7 [16%]). Six eyes (14%) had retained intraocular foreign bodies. Mean presenting logarithm of the minimum angle of resolution visual acuity was 1.64 ± 0.83, whereas mean final logarithm of the minimum angle of resolution visual acuity was 1.01 ± 0.96 (P = 0.004). Two eyes (4.7%) had no light perception vision at final examination. Seventeen (40%) patients developed a traumatic cataract, and 2 (4.7%) had dislocated lens fragments. Most common findings on presentation included vitreous hemorrhage (n = 30 [70%]) and hyphema (n = 28 [64%]). Two eyes (4.7%) had a retinal detachment at presentation, and 10 (23%) developed a retinal detachment during follow-up visits. Anatomical success was observed in 11 eyes (92%) with a retinal detachment. Three eyes (7.0%) became phthisical or prephthisical, and 1 was enucleated for severe pain. No eyes developed endophthalmitis or sympathetic ophthalmia. This is the largest compilation of nail gun-related open-globe injury reported to date. Posterior segment complications, noted in the majority of cases, likely contributed to the overall guarded visual outcomes. Preventative measures for eye protection should be strictly followed while using nail guns.

Detecting Moho Boundary under Taiwan with Wide-angle Data by Ray-tracing Method - The TAIGER Project

NASA Astrophysics Data System (ADS)

Kuo, Y. N.; Wang, C.; Okaya, D. A.

2009-12-01

Taiwan is located at the converging boundary of the Eurasian plate and the Philippine Sea plate, and is one of the most rapidly uplifting orogeny in the world. The geological structure is relatively complicated. There exist several models of tectonic collisions from the thin-skinned thrust, the lithospheric collision, to uplifting by buoyancy. The shape of Moho should be a key factor to evaluate these models. In this study, we try to detect the Moho beneath Taiwan using the newly collected wide-angle data from the Taiwan Integrated Geodynamic Research (TAIGER) project. The results could be of help to set up some constrains for the Taiwan tectonics. The TAIGER project is a collaboration between America and Taiwan. The land stations collected two parts of data (land and marine) generated by active sources. The land part was carried out in 2008/2~3, which created 6 kinds of data from explosion sources including: 1) 3 E-W wide-angle reflections of Texans arrays; 2) 2 N-S seismometer arrays; 3) the seismic networks of Central Weather Bureau(CWB) and Institute of Earth Science(IES) over the island; 4) a short array of RT130; 5) 2 short period OBS arrays in the Taiwan Strait; 6) 2 temporary seismic arrays in Fujan, mainland China. The marine part was carried out in 2009/4~6, which provided 4 kinds of data from air-gun sources including: 1) 4 wide-angle refractions of E-W RT130 arrays; 2) 2 N-S seismometer arrays; 3) the CWB network; 4) the broad band array in Taiwan for Seismology(BATS). In this study, we focus on analyzing the wide-angle data, which contain land explosion data, onshore-offshore data, OBS data and mainland data, especially concentrate on the line in the southern Taiwan (Transect T4). We make a summary of the TAIGER project and show several plots of real data and arrivals. A 2D E-W velocity model was constructed from the mainland side to the ocean side about 600 km long using the ray-tracing method with layer-striping technique. The preliminary results are: 1) the distribution of Moho depth is basically getting deeper from the west to the east, but becoming shallower rapidly in the area of Coast Range; 2) the crust thickens to the range of 40 km in the mountain area; 3) the Moho depth is shallower than 30 km in the Peikang High and deeper than 32 km at the coast line of Fujan, no crust bulge in the Taiwan Strait; 4) the structures derived from PmP phase and Pn phase from land explosions and onshore-offshore air-gun shots are highly consistent.

High-Power Helicon Double Gun Thruster

NASA Astrophysics Data System (ADS)

Murakami, Nao

While chemical propulsion is necessary to launch a spacecraft from a planetary surface into space, electric propulsion has the potential to provide significant cost savings for the orbital transfer of payloads between planets. Due to extended wave particle interactions, a plasma thruster that can operate in the 100 kW to several MW power regime can only be attained by increasing the size of the thruster, or by using an array of plasma thrusters. The High-Power Helicon (HPH) Double Gun thruster experiment examines whether firing two helicon thrusters in parallel produces an exhaust velocity higher than the exhaust velocity of a single thruster. The scaling law that relates the downstream plasma velocity with the number of helicon antennae is derived, and compared with the experimental result. In conjunction with data analysis, two digital filtering algorithms are developed to filter out the noise from helicon antennae. The scaling law states that the downstream plasma velocity is proportional to square root of the number of helicon antennae, which is in agreement with the experimental result.

BIOMECHANICS OF HEAD INJURY IN OLYMPIC TAEKWONDO AND BOXING

PubMed Central

Fife, G.P.; Pieter, W.

2013-01-01

Objective The purpose was to examine differences between taekwondo kicks and boxing punches in resultant linear head acceleration (RLA), head injury criterion (HIC15), peak head velocity, and peak foot and fist velocities. Data from two existing publications on boxing punches and taekwondo kicks were compared. Methods For taekwondo head impacts a Hybrid II Crash Dummy (Hybrid II) head was instrumented with a tri-axial accelerometer mounted inside the Hybrid II head. The Hybrid II was fixed to a height-adjustable frame and fitted with a protective taekwondo helmet. For boxing testing, a Hybrid III Crash Dummy head was instrumented with an array of tri-axial accelerometers mounted at the head centre of gravity. Results Differences in RLA between the roundhouse kick (130.11±51.67 g) and hook punch (71.23±32.19 g, d = 1.39) and in HIC15 (clench axe kick: 162.63±104.10; uppercut: 24.10±12.54, d = 2.29) were observed. Conclusions Taekwondo kicks demonstrated significantly larger magnitudes than boxing punches for both RLA and HIC. PMID:24744497

Model-based Estimation for Pose, Velocity of Projectile from Stereo Linear Array Image

NASA Astrophysics Data System (ADS)

Zhao, Zhuxin; Wen, Gongjian; Zhang, Xing; Li, Deren

2012-01-01

The pose (position and attitude) and velocity of in-flight projectiles have major influence on the performance and accuracy. A cost-effective method for measuring the gun-boosted projectiles is proposed. The method adopts only one linear array image collected by the stereo vision system combining a digital line-scan camera and a mirror near the muzzle. From the projectile's stereo image, the motion parameters (pose and velocity) are acquired by using a model-based optimization algorithm. The algorithm achieves optimal estimation of the parameters by matching the stereo projection of the projectile and that of the same size 3D model. The speed and the AOA (angle of attack) could also be determined subsequently. Experiments are made to test the proposed method.

40 CFR 63.4081 - Am I subject to this subpart?

Code of Federal Regulations, 2010 CFR

2010-07-01

... appliance parts and products; (2) Preparation of a coating for application (e.g., mixing in thinners and..., spray guns or dip tanks; (4) Application of porcelain enamel, powder coating, and asphalt interior...) Cleaning of equipment used in coating operations (e.g., application equipment, hangers, racks); (7) Storage...

Arc-Dynamic Calculations In The Rail Gun

DTIC Science & Technology

1983-11-01

16. C,A.L. Westerdahl , 1. Pinto, G,L, Ferrentino, T. Gora, ’Larse-Railsun Residue Material Photoelectron Spectroscopy,’ IEEE Trans. on (1983). D...8217 Ballistic Research Laboratory Report No. ARBRL-TR-02530, Oct 83. 15. J.D. Powell, private communication. • 16. C.A.L. Westerdahl , J. Pinto, G.L

Cross-Gender Violence Perpetration and Victimization among Early Adolescents and Associations with Attitudes toward Dating Conflict

ERIC Educational Resources Information Center

Windle, Michael; Mrug, Sylvie

2009-01-01

This study examined gender differences in cross-gender violence perpetration and victimization (ranging from mild, e.g., push, to severe, e.g., assault with a knife or gun) and attitudes toward dating conflict, among an urban sample of 601 early adolescents (78% African-American). Comparisons across gender groups for cross-gender (e.g.,…

32 CFR 644.112 - Applicable statutes in condemnation proceedings.

Code of Federal Regulations, 2010 CFR

2010-07-01

... additional permanent air bases and depots, enlarge existing air bases and depots, bombing and machine gun... compensation. (2) Flood control. (i) Act of Congress approved March 1, 1917 (39 Stat. 950, 33 U.S.C. 701) makes...) applicable to flood control works. (ii) Section 6 of the Act of Congress approved August 18, 1941 (55 Stat...

32 CFR 644.112 - Applicable statutes in condemnation proceedings.

Code of Federal Regulations, 2013 CFR

2013-07-01

... additional permanent air bases and depots, enlarge existing air bases and depots, bombing and machine gun... compensation. (2) Flood control. (i) Act of Congress approved March 1, 1917 (39 Stat. 950, 33 U.S.C. 701) makes...) applicable to flood control works. (ii) Section 6 of the Act of Congress approved August 18, 1941 (55 Stat...

32 CFR 644.112 - Applicable statutes in condemnation proceedings.

Code of Federal Regulations, 2012 CFR

2012-07-01

... additional permanent air bases and depots, enlarge existing air bases and depots, bombing and machine gun... compensation. (2) Flood control. (i) Act of Congress approved March 1, 1917 (39 Stat. 950, 33 U.S.C. 701) makes...) applicable to flood control works. (ii) Section 6 of the Act of Congress approved August 18, 1941 (55 Stat...

32 CFR 644.112 - Applicable statutes in condemnation proceedings.

Code of Federal Regulations, 2011 CFR

2011-07-01

... additional permanent air bases and depots, enlarge existing air bases and depots, bombing and machine gun... compensation. (2) Flood control. (i) Act of Congress approved March 1, 1917 (39 Stat. 950, 33 U.S.C. 701) makes...) applicable to flood control works. (ii) Section 6 of the Act of Congress approved August 18, 1941 (55 Stat...

32 CFR 644.112 - Applicable statutes in condemnation proceedings.

Code of Federal Regulations, 2014 CFR

2014-07-01

... additional permanent air bases and depots, enlarge existing air bases and depots, bombing and machine gun... compensation. (2) Flood control. (i) Act of Congress approved March 1, 1917 (39 Stat. 950, 33 U.S.C. 701) makes...) applicable to flood control works. (ii) Section 6 of the Act of Congress approved August 18, 1941 (55 Stat...

Photocathodes for RF photoinjectors

NASA Astrophysics Data System (ADS)

Michelato, P.

1997-02-01

Over the past ten years photocathodes have been extensively used as high-brightness electron sources in RF guns. In this paper, I present a general review of the alkali-based high quantum efficiency (QE) photoemitters (e.g. Cs 3Sb, K 2CsSb and Cs 2Te), together with a comparative analysis of the different preparation procedures and the results obtained, both in the preparation chambers and in RF guns. The need to increase the photocathode reliability has provided the impetus to get an R&D activity to go over the alchemy of photocathode preparation procedure. In this paper, I will discuss the results so far obtained in different laboratories, both by using traditional investigation strategy (e.g. QE and RF behavior) and by means of surface science techniques as Auger Electron Spectroscopy (AES) and X-ray Photoelectron Spectroscopy (XPS). Alkali antimonides have been used at first in the RF gun due to the high QE response to the green light of the Nd:YLF second-harmonic radiation. Measurements have confirmed the high reactivity of the alkali antimonide photocathodes to the residual gases: this fact makes their use in RF guns not practical, mainly for short lifetimes. Further investigations have shown that the choice of the substratum preparation procedure and chemical composition plays a fundamental role in the photocathode performance, both from the point of view of the QE and the operative lifetime and ruggedness to gas exposition. Cesium telluride (Cs 2Te) prepared on a molybdenum substratum seems to be, nowadays, the best compromise, in terms of preparation procedure reliability and ruggedness, that now the characteristics and drawbacks of this material are well understood (e.g. the need of an UV laser source). Future possible developments will be discussed. In particular, the measurement and the control of the thermal emittance and the time response could be an important task.

International Space Station-Based Electromagnetic Launcher for Space Science Payloads

NASA Technical Reports Server (NTRS)

Jones, Ross M.

2013-01-01

A method was developed of lowering the cost of planetary exploration missions by using an electromagnetic propulsion/launcher, rather than a chemical-fueled rocket for propulsion. An electromagnetic launcher (EML) based at the International Space Station (ISS) would be used to launch small science payloads to the Moon and near Earth asteroids (NEAs) for the science and exploration missions. An ISS-based electromagnetic launcher could also inject science payloads into orbits around the Earth and perhaps to Mars. The EML would replace rocket technology for certain missions. The EML is a high-energy system that uses electricity rather than propellant to accelerate payloads to high velocities. The most common type of EML is the rail gun. Other types are possible, e.g., a coil gun, also known as a Gauss gun or mass driver. The EML could also "drop" science payloads into the Earth's upper

Diolistics: incorporating fluorescent dyes into biological samples using a gene gun

PubMed Central

O’Brien, John A.; Lummis, Sarah C.R.

2007-01-01

The hand-held gene gun provides a rapid and efficient method of incorporating fluorescent dyes into cells, a technique that is becoming known as diolistics. Transporting fluorescent dyes into cells has, in the past, used predominantly injection or chemical methods. The use of the gene gun, combined with the new generation of fluorescent dyes, circumvents some of the problems of using these methods and also enables the study of cells that have proved difficult traditionally to transfect (e.g. those deep in tissues and/or terminally differentiated); in addition, the use of ion- or metabolite-sensitive dyes provides a route to study cellular mechanisms. Diolistics is also ideal for loading cells with optical nanosensors – nanometre-sized sensors linked to fluorescent probes. Here, we discuss the theoretical considerations of using diolistics, the advantages compared with other methods of inserting dyes into cells and the current uses of the technique, with particular consideration of nanosensors. PMID:17945370

MIT modular x-ray source systems for the study of plasma diagnostics

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

Coleman, J.W.; Wenzel, K.W.; Petrasso, R.D.

1992-10-01

Two new x-ray source systems are now on line at our facility. Each provides an {ital e}-beam to 25 kV. Targets are interchangeable between machines, and four x-ray detectors may be used simultaneously with a target. The gridded {ital e}-gun of the RACEHORSE system gives a 0.5--1.0-cm pulsable spot on target. The nongridded {ital e}-gun of the SCORPION system provides a 0.3-mm or smaller dc microspot on target. RACEHORSE is being used to study and characterize type-II diamond photoconductors for use in diagnosing plasmas, while SCORPION is being used to develop a slitless spectrograph using photographic film. Source design detailsmore » and some RACEHORSE results are presented.« less

15 CFR 922.71 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-01-01

...). Stowed and not available for immediate use means not readily accessible for immediate use, e.g., by being... (such as spear shafts being kept separate from spear guns). [74 FR 3260, Jan. 16, 2009] ...

Whose guns are stolen? The epidemiology of Gun theft victims.

PubMed

Hemenway, David; Azrael, Deborah; Miller, Matthew

2017-12-01

Gun theft is an important source of guns used by criminals. Yet no empirical work has focused on the characteristics of gun owners that distinguish those who have had their guns stolen from those who have not. In this study, we examine the demographics and behavioral characteristics of gun owners who report having had a gun stolen. Data come from a nationally representative probability-based online survey conducted in April 2015, with a linked follow-up survey in November 2015 that asked gun owners about any theft of their guns in the past 5 years. Of 1,604 gun-owning respondents, 2.4% (95% CI 1.6,3.6) reported that one or more guns had been stolen, with a mean number of guns stolen per theft of 1.5 (95% CI 1.0,2.0]. Risk factors for having a gun stolen were owning 6 or more guns, owning guns for protection, carrying a gun in the past month, storing guns unsafely, and living in the South region of the United States. The South accounts for 37% of US households, 43% of gun owners, and two-thirds of all gun thefts. We estimate that there are approximately 250,000 gun theft incidents per year, with about 380,000 guns stolen. We find that certain types of gun owners-who own many guns, who carry guns, and who do not store guns safely-are at higher risk to have their guns stolen. Tracing data show that states in the South are exporters of crime guns used in other states. Our survey results find that the majority of guns stolen in the US come from the South.

Lead exposure at firing ranges-a review.

PubMed

Laidlaw, Mark A S; Filippelli, Gabriel; Mielke, Howard; Gulson, Brian; Ball, Andrew S

2017-04-04

Lead (Pb) is a toxic substance with well-known, multiple, long-term, adverse health outcomes. Shooting guns at firing ranges is an occupational necessity for security personnel, police officers, members of the military, and increasingly a recreational activity by the public. In the United States alone, an estimated 16,000-18,000 firing ranges exist. Discharge of Pb dust and gases is a consequence of shooting guns. The objectives of this study are to review the literature on blood lead levels (BLLs) and potential adverse health effects associated with the shooting population. The search terms "blood lead", "lead poisoning", "lead exposure", "marksmen", "firearms", "shooting", "guns", "rifles" and "firing ranges" were used in the search engines Google Scholar, PubMed and Science Direct to identify studies that described BLLs in association with firearm use and health effects associated with shooting activities. Thirty-six articles were reviewed that included BLLs from shooters at firing ranges. In 31 studies BLLs > 10 μg/dL were reported in some shooters, 18 studies reported BLLs > 20 μg/dL, 17 studies > 30 μg/d, and 15 studies BLLs > 40 μg/dL. The literature indicates that BLLs in shooters are associated with Pb aerosol discharge from guns and air Pb at firing ranges, number of bullets discharged, and the caliber of weapon fired. Shooting at firing ranges results in the discharge of Pb dust, elevated BLLs, and exposures that are associated with a variety of adverse health outcomes. Women and children are among recreational shooters at special risk and they do not receive the same health protections as occupational users of firing ranges. Nearly all BLL measurements compiled in the reviewed studies exceed the current reference level of 5 μg/dL recommended by the U.S. Centers for Disease Control and Prevention/National Institute of Occupational Safety and Health (CDC/NIOSH). Thus firing ranges, regardless of type and user classification, currently constitute a significant and unmanaged public health problem. Prevention includes clothing changed after shooting, behavioural modifications such as banning of smoking and eating at firing ranges, improved ventilation systems and oversight of indoor ranges, and development of airflow systems at outdoor ranges. Eliminating lead dust risk at firing ranges requires primary prevention and using lead-free primers and lead-free bullets.

Intestinal Helminth Infections in Feral Cats and a Raccoon Dog on Aphaedo Island, Shinan-gun, with a Special Note on Gymnophalloides seoi Infection in Cats

PubMed Central

Shin, Eun-Hee; Park, Jae-Hwan; Guk, Sang-Mee; Kim, Jae-Lip

2009-01-01

Four feral cats and a raccoon dog purchased from a local collector on Aphaedo Island, Shinan-gun, where human Gymnophalloides seoi infections are known to be prevalent, were examined for their intestinal helminth parasites. From 2 of 4 cats, a total of 310 adult G. seoi specimens were recovered. Other helminths detected in cats included Heterophyes nocens (1,527 specimens), Pygidiopsis summa (131), Stictodora fuscata (4), Acanthotrema felis (2), Spirometra erinacei (15), toxocarids (4), and a hookworm (1). A raccoon dog was found to be infected with a species of echinostome (55), hookworms (7), toxocarids (3), P. summa (3), and S. erinacei (1). No G. seoi was found in the raccoon dog. The results indicate that feral cats and raccoon dogs on Aphaedo are natural definitive hosts for intestinal trematodes and cestodes, including G. seoi, H. nocens, and S. erinacei. It has been first confirmed that cats, a mammalian species other than humans, play the role of a natural definitive host for G. seoi on Aphaedo Island. PMID:19488429

Intestinal helminth infections in feral cats and a raccoon dog on Aphaedo Island, Shinan-gun, with a special note on Gymnophalloides seoi infection in cats.

PubMed

Shin, Eun-Hee; Park, Jae-Hwan; Guk, Sang-Mee; Kim, Jae-Lip; Chai, Jong-Yil

2009-06-01

Four feral cats and a raccoon dog purchased from a local collector on Aphaedo Island, Shinan-gun, where human Gymnophalloides seoi infections are known to be prevalent, were examined for their intestinal helminth parasites. From 2 of 4 cats, a total of 310 adult G. seoi specimens were recovered. Other helminths detected in cats included Heterophyes nocens (1,527 specimens), Pygidiopsis summa (131), Stictodora fuscata (4), Acanthotrema felis (2), Spirometra erinacei (15), toxocarids (4), and a hookworm (1). A raccoon dog was found to be infected with a species of echinostome (55), hookworms (7), toxocarids (3), P. summa (3), and S. erinacei (1). No G. seoi was found in the raccoon dog. The results indicate that feral cats and raccoon dogs on Aphaedo are natural definitive hosts for intestinal trematodes and cestodes, including G. seoi, H. nocens, and S. erinacei. It has been first confirmed that cats, a mammalian species other than humans, play the role of a natural definitive host for G. seoi on Aphaedo Island.

Marshall Space Flight Center's Impact Testing Facility Capabilities

NASA Technical Reports Server (NTRS)

Evans, Steve; Finchum, Andy; Hubbs, Whitney; Gray, Perry

2008-01-01

Marshall Space Flight Center's (MSFC) Impact Testing Facility (ITF) serves as an important installation for space and missile related materials science research. The ITF was established and began its research in spacecraft debris shielding in the early 1960s, then played a major role in the International Space Station debris shield development. As NASA became more interested in launch debris and in-flight impact concerns, the ITF grew to include research in a variety of impact genres. Collaborative partnerships with the DoD led to a wider range of impact capabilities being relocated to MSFC as a result of the closure of Particle Impact Facilities in Santa Barbara, California, The Particle Impact Facility had a 30 year history in providing evaluations of aerospace materials and components during flights through rain, ice, and solid particle environments at subsonic through hypersonic velocities. The facility's unique capabilities were deemed a 'National Asset' by the DoD, The ITF now has capabilities including environmental, ballistic, and hypervelocity impact testing utilizing an array of air, powder, and two-stage light gas guns to accommodate a variety of projectile and target types and sizes. Relocated test equipment was dated and in need of upgrade. Numerous upgrades including new instrumentation, triggering circuitry, high speed photography, and optimized sabot designs have been implemented. Other recent research has included rain drop demise characterization tests to obtain data for inclusion in on-going model development. Future ITF improvements will be focused on continued instrumentation and performance enhancements. These enhancements will allow further, more in-depth, characterization of rain drop demise characterization and evaluation of ice crystal impact. Performance enhancements also include increasing the upper velocity limit of the current environmental guns to allow direct environmental simulation for missile components. The current and proposed ITF capabilities range from rain to micrometeoroids allowing the widest test parameter range possible for materials investigations in support of space, atmospheric, and ground environments. These test capabilities including hydrometeor, single/multi-particle, ballistic gas guns, exploding wire gun, and light gas guns combined with Smooth Particle Hydrodynamics Code (SPHC) simulations represent the widest range of impact test capabilities in the country.

Public Support for Gun Violence Prevention Policies Among Gun Owners and Non-Gun Owners in 2017.

PubMed

Barry, Colleen L; Webster, Daniel W; Stone, Elizabeth; Crifasi, Cassandra K; Vernick, Jon S; McGinty, Emma E

2018-07-01

To compare public support for 24 different gun policies between gun owners and non-gun owners in 2017. We fielded a national public opinion survey in January 2017 using an online panel to measure US adults' support for 24 gun policies. We compared support among gun owners and non-gun owners. For 23 of the 24 policies examined, most respondents supported restricting or regulating gun ownership. Only 8 of 24 policies had greater than a 10-point support gap between gun owners and non-gun owners. Policies with high public support and minimal support gaps by gun ownership status included universal background checks, greater accountability for licensed gun dealers unable to account for their inventory, higher safety training standards for concealed carry permit holders, improved reporting of records related to mental illness for background checks, gun prohibitions for persons subject to temporary domestic violence restraining orders, and gun violence restraining orders. Public Health Implications. Although there are important areas where Americans disagree on guns, large majorities of both gun owners and non-gun owners strongly support measures to strengthen US gun laws.

A Robust High Current Density Electron Gun

NASA Astrophysics Data System (ADS)

Mako, F.; Peter, W.; Shiloh, J.; Len, L. K.

1996-11-01

Proof-of-principle experiments are proposed to validate a new concept for a robust, high-current density Pierce electron gun (RPG) for use in klystrons and high brightness electron sources for accelerators. This rugged, long-life electron gun avoids the difficulties associated with plasma cathodes, thermionic emitters, and field emission cathodes. The RPG concept employs the emission of secondary electrons in a transmission mode as opposed to the conventional mode of reflection, i.e., electrons exit from the back face of a thin negative electron affinity (NEA) material, and in the same direction as the incident beam. Current amplification through one stage of a NEA material could be over 50 times. The amplification is accomplished in one or more stages consisting of one primary emitter and one or more secondary emitters. The primary emitter is a low current density robust emitter (e.g., thoriated tungsten). The secondary emitters are thin NEA electrodes which emit secondary electrons in the same direction as the incident beam. Specific application is targeted for a klystron gun to be used by SLAC with a cold cathode at 30-40 amps/cm^2 output from the secondary emission stage, a ~2 μs pulse length, and ~200 pulses/second.

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Comparison of the immune responses in BALB/c mice following immunization with DNA-based and live attenuated vaccines delivered via different routes.

PubMed

Cai, Ming-sheng; Deng, Shu-xuan; Li, Mei-li

2013-02-18

The objective of this study was to compare immune responses induced in BALB/c mice following immunization with pcDNA-GPV-VP2 DNA by gene gun bombardment (6 μg) or by intramuscular (im) injection (100 μg) with the responses to live attenuated vaccine by im injection (100 μl). pcDNA3.1 (+) and physiological saline were used as controls. Peripheral blood samples were collected at 3, 7, 14, 21, 28, 35, 49, 63, 77 and 105 d after immunization. T lymphocyte proliferation was analyzed by MTT assay and enumeration of CD4(+), and CD8(+) T cell populations in peripheral blood was performed by flow cytometric analysis. Indirect ELISA was used to detect IgG levels. Cellular and humoral responses were induced by pcDNA-GPV-VP2 DNA and live virus vaccines. No differences were observed in T cell proliferation and CD8(+) T cell responses induced by the genetic vaccine regardless of the route of delivery. However, CD4(+) T cell responses and humoral immunity were enhanced in following gene gun immunization compared with im injection of the genetic vaccine. Cellular and humoral immunity was enhanced in following gene gun delivery of the genetic vaccine compared with the live attenuated vaccine. In conclusion, the pcDNA-GPV-VP2 DNA vaccine induced enhanced cellular and humoral immunity compared with that induced by the live attenuated vaccine. Copyright © 2012 Elsevier Ltd. All rights reserved.

Deep Structures of The Angola Margin

NASA Astrophysics Data System (ADS)

Moulin, M.; Contrucci, I.; Olivet, J.-L.; Aslanian, D.; Géli, L.; Sibuet, J.-C.

1 Ifremer Centre de Brest, DRO/Géosciences Marines, B.P. 70, 29280 Plouzané cedex (France) mmoulin@ifremer.fr/Fax : 33 2 98 22 45 49 2 Université de Bretagne Occidentale, Institut Universitaire Europeen de la Mer, Place Nicolas Copernic, 29280 Plouzane (France) 3 Total Fina Elf, DGEP/GSR/PN -GEOLOGIE, 2,place de la Coupole-La Defense 6, 92078 Paris la Defense Cedex Deep reflection and refraction seismic data were collected in April 2000 on the West African margin, offshore Angola, within the framework of the Zaiango Joint Project, conducted by Ifremer and Total Fina Elf Production. Vertical multichannel reflection seismic data generated by a « single-bubble » air gun array array (Avedik et al., 1993) were recorded on a 4.5 km long, digital streamer, while refraction and wide angle reflection seismic data were acquired on OBSs (Ocean Bottom Seismometers). Despite the complexity of the margin (5 s TWT of sediment, salt tectonics), the combination of seismic reflection and refraction methods results in an image and a velocity model of the ground structures below the Aptian salt layer. Three large seismic units appear in the reflection seismic section from the deep part on the margin under the base of salt. The upper seismic unit is layered with reflectors parallel to the base of the salt ; it represents unstructured sediments, filling a basin. The middle unit is seismically transparent. The lower unit is characterized by highly energetic reflectors. According to the OBS refraction data, these two units correspond to the continental crust and the base of the high energetic unit corresponds to the Moho. The margin appears to be divided in 3 domains, from east to west : i) a domain with an unthinned, 30 km thick, continental crust ; ii) a domain located between the hinge line and the foot of the continental slope, where the crust thins sharply, from 30 km to less than 7 km, this domain is underlain by an anormal layer with velocities comprising between 7,2 and 7,4 km/s. The maximum thickness of this layer is located where the crust shows the strongest thinning at the foot of the continental slope ; and iii) a transitional domain, 160 km wide, with an average crustal thickness of 6 km. Moreover, no tilted blocks nor detachment faults are observed on the reflection seismic sections. The consequences of these observations on the models of crustal thinning classically used in the litterature are examined. Avedik, F., V. Renard, J-P. Allenou, B. Morvan, "Single bubble" air gun for deep exploration, Geophysics, 58, 366-382, 1993.

Powerful inhibition of in-vivo growth of experimental hepatic cancers by bombesin/gastrin-releasing peptide antagonist RC-3940-II.

PubMed

Szepeshazi, Karoly; Schally, Andrew V; Rick, Ferenc G; Block, Norman L; Vidaurre, Irving; Halmos, Gabor; Szalontay, Luca

2012-10-01

Hepatic carcinoma is a major health problem worldwide. Its incidence is increasing in Western countries and there is currently no effective systemic therapy against it. Targeted treatment modalities developed in the past few years have provided very limited success. Development of new treatment strategies is therefore essential. We investigated the effects of bombesin/gastrin-releasing peptide (BN/GRP) antagonist RC-3940-II on experimental human liver cancers in nude mice. SK-Hep-1 and Hep-G2 cancers transplanted subcutaneously into nude mice were treated daily with 10 or 20 µg of RC-3940-II. Tumor growth was monitored for 50-184 days in five experiments. Tumor gene expression was analyzed with PCR array and protein expression by immunoblotting. Characteristics of BN/GRP receptors in the tumors were analyzed by binding assays. Effects of RC-3940-II on cell proliferation were investigated in vitro. RC-3940-II inhibited the growth of SK-Hep-1 cancers in nude mice by 65-98%, with total regression in 9 of 36 tumors in three experiments. The BN/GRP antagonist inhibited the growth of Hep-G2 cancers as well by 73-82% in two experiments, being effective even on originally large tumors. Gene expression analysis showed an increase in several angiogenesis inhibitors and decrease in proangiogenic genes after RC-3940-II treatment. Receptor assays demonstrated high-affinity binding sites for BN/GRP in both tumor lines. BN/GRP antagonist RC-3940-II powerfully inhibits growth of SK-Hep-1 and Hep-G2 cancers in nude mice. Its effect may be linked to changes in expression of those cancer genes important in angiogenesis, invasion, and metastasis. RC-3940-II may be considered for further investigations in treatment of liver cancers.

State Gun Law Environment and Youth Gun Carrying in the United States.

PubMed

Xuan, Ziming; Hemenway, David

2015-11-01

Gun violence and injuries pose a substantial threat to children and youth in the United States. Existing evidence points to the need for interventions and policies for keeping guns out of the hands of children and youth. (1) To examine the association between state gun law environment and youth gun carrying in the United States, and (2) to determine whether adult gun ownership mediates this association. This was a repeated cross-sectional observational study design with 3 years of data on youth gun carrying from US states. The Youth Risk Behavior Survey comprises data of representative samples of students in grades 9 to 12 from biennial years of 2007, 2009, and 2011. We hypothesized that states with more restrictive gun laws have lower rates of youth gun carrying, and this association is mediated by adult gun ownership. State gun law environment as measured by state gun law score. Youth gun carrying was defined as having carried a gun on at least 1 day during the 30 days before the survey. In the fully adjusted model, a 10-point increase in the state gun law score, which represented a more restrictive gun law environment, was associated with a 9% decrease in the odds of youth gun carrying (adjusted odds ratio [AOR], 0.91 [95% CI, 0.86-0.96]). Adult gun ownership mediated the association between state gun law score and youth gun carrying (AOR, 0.94 [ 95% CI, 0.86-1.01], with 29% attenuation of the regression coefficient from -0.09 to -0.07 based on bootstrap resampling). More restrictive overall gun control policies are associated with a reduced likelihood of youth gun carrying. These findings are relevant to gun policy debates about the critical importance of strengthening overall gun law environment to prevent youth gun carrying.

Children and firearms in the home: a Southwestern Ohio Ambulatory Research Network (SOAR-Net) study.

PubMed

Forbis, Shalini G; McAllister, Terence R; Monk, Susan M; Schlorman, Christopher A; Stolfi, Adrienne; Pascoe, John M

2007-01-01

To ascertain the prevalence of gun ownership, gun safety education, and parental attitudes on gun counseling in a Midwestern sample. Parents seeking care at participating practices in the Southwestern Ohio Ambulatory Research Network were recruited to complete a survey about gun ownership, gun safety education, and gun counseling attitudes. Attitudes and beliefs were compared between gun owners and non-gun owners. Twenty-four percent of respondents had at least 1 gun in the home. Military families were more likely to own a gun than civilian families (28% vs 18%, P = .001). Fifty-two percent of sample children have received gun safety education. Eight percent indicated that a physician had asked about guns or discussed gun safety issues during an office visit. A majority of parents indicated that physicians should ask about guns in the home (69%) and advise parents on safe storage (75%), but they should not advise parents to remove guns from the home (12% of gun owners, 42% of non-gun owners). Despite the morbidity and mortality associated with guns, physicians in this study do not seem to be addressing this risk with families. A majority of gun owners do not agree that physicians should counsel the removal of guns from the home but agree that they should discuss safe gun storage information.

78 FR 77493 - Agency Information Collection Activities; Proposed Collection; Comments Requested: Open Letter to...

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2013-12-23

..., mechanical, or other technological collection techniques or other forms of information technology, e.g... statutory requirements contained in the Gun Control Act qualify as alternatives to a National Instant...

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2010-10-27

... other forms of information technology, e.g., permitting electronic submission of responses. Overview of... collection is to ensure that only State permits that meet the statutory requirements contained in the Gun...

77 FR 37920 - Agency Information Collection Activities; Proposed Collection; Comments Requested: Firearms...

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2012-06-25

... other technological collection techniques or other forms of information technology, e.g., permitting...-profit. Need for Collection The form is used to determine the eligibility, under the Gun Control Act (GCA...

Gun Shows and Gun Violence: Fatally Flawed Study Yields Misleading Results

PubMed Central

Hemenway, David; Webster, Daniel; Pierce, Glenn; Braga, Anthony A.

2010-01-01

A widely publicized but unpublished study of the relationship between gun shows and gun violence is being cited in debates about the regulation of gun shows and gun commerce. We believe the study is fatally flawed. A working paper entitled “The Effect of Gun Shows on Gun-Related Deaths: Evidence from California and Texas” outlined this study, which found no association between gun shows and gun-related deaths. We believe the study reflects a limited understanding of gun shows and gun markets and is not statistically powered to detect even an implausibly large effect of gun shows on gun violence. In addition, the research contains serious ascertainment and classification errors, produces results that are sensitive to minor specification changes in key variables and in some cases have no face validity, and is contradicted by 1 of its own authors’ prior research. The study should not be used as evidence in formulating gun policy. PMID:20724672

Gun shows and gun violence: fatally flawed study yields misleading results.

PubMed

Wintemute, Garen J; Hemenway, David; Webster, Daniel; Pierce, Glenn; Braga, Anthony A

2010-10-01

A widely publicized but unpublished study of the relationship between gun shows and gun violence is being cited in debates about the regulation of gun shows and gun commerce. We believe the study is fatally flawed. A working paper entitled "The Effect of Gun Shows on Gun-Related Deaths: Evidence from California and Texas" outlined this study, which found no association between gun shows and gun-related deaths. We believe the study reflects a limited understanding of gun shows and gun markets and is not statistically powered to detect even an implausibly large effect of gun shows on gun violence. In addition, the research contains serious ascertainment and classification errors, produces results that are sensitive to minor specification changes in key variables and in some cases have no face validity, and is contradicted by 1 of its own authors' prior research. The study should not be used as evidence in formulating gun policy.

Optimized Breech Location in the Harry Diamond Laboratories 4-Inch Gas Gun

DTIC Science & Technology

1982-04-01

GAMA-iy*SQRrA BAR*(1-FRAC L~(GAMA-1))) IF INIT_G(BRL%)<=START TJ - THEN PRINT #BRL% USTNG FORM4$,INIT G(BRL%).VEL ELSE FLAG( BRU ) = 1 - 130 NEXT...CA 93041 COMMANDER DAVID W. TAYLOR NAVAL SHIP RESEARCH S DEVELOPMENT CENTER ATTN ELIZABETH DEMPSEY, CODE 534 ATTN PAUL GRANVILLE, CODE 581

Experimental Tests of UltraFlex Array Designs in Low Earth Orbital and Geosynchronous Charging Environments

NASA Technical Reports Server (NTRS)

Galofaro, Joel T.; Vayner, Boris V.; Hillard, Grover B.

2011-01-01

The present ground based investigations give the first definitive look describing the expected on-orbit charging behavior of Orion UltraFlex array coupons in the Low Earth Orbital and Geosynchronous Environments. Furthermore, it is important to note that the LEO charging environment also applies to the International Space Station as well as to the lunar mission charging environments. The GEO charging environment includes the bounding case for all lunar orbital and lunar surface mission environments. The UltraFlex thin film photovoltaic array technology has been targeted to become the sole power system for life support and on-orbit power for the manned Aires Crew Exploration Vehicle. It is therefore, crucial to gain an understanding of the complex charging behavior to answer some of the basic performance and survivability issues in an attempt to ascertain that a single UltraFlex array design will be able to cope with the projected worst case LEO and GEO charging environments. Testing was limited to four array coupons, two coupons each from two different array manufactures, Emcore and Spectrolab. The layout of each array design is identical and varies only in the actual cell technology used. The individual array cells from each manufacturer have an antireflection layered coating and come in two different varieties either uncoated (only AR coating) or coated with a thin conducting ITO layer. The LEO Plasma tests revealed that all four coupons passed the arc threshold -120 V bias tests. GEO electron gun charging tests revealed that only front side area of ITO coated coupons passed tests. Only the Emcore AR array passed backside Stage 2 GEO Tests.

76 FR 45863 - Agency Information Collection Activities; Proposed Collection; Comments Requested: Firearms...

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2011-08-01

... other technological collection techniques or other forms of information technology, e.g., permitting... Collection The form is used to determine the eligibility (under the Gun Control Act) of a person to receive a...

77 FR 51576 - Agency Information Collection Activities; Proposed Collection; Comments Request: Firearms...

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2012-08-24

... techniques or other forms of information technology, e.g., permitting electronic submission of responses... used to determine the eligibility, under the Gun Control Act (GCA), of a person to receive a firearm...

Gun ownership and social gun culture

PubMed Central

Kalesan, Bindu; Villarreal, Marcos D; Keyes, Katherine M; Galea, Sandro

2016-01-01

We assessed gun ownership rates in 2013 across the USA and the association between exposure to a social gun culture and gun ownership. We used data from a nationally representative sample of 4000 US adults, from 50 states and District of Columbia, aged >18 years to assess gun ownership and social gun culture performed in October 2013. State-level firearm policy information was obtained from the Brady Law Center and Injury Prevention and Control Center. One-third of Americans reported owning a gun, ranging from 5.2% in Delaware to 61.7% in Alaska. Gun ownership was 2.25-times greater among those reporting social gun culture (PR=2.25, 95% CI 2.02 to 2.52) than those who did not. In conclusion, we found strong association between social gun culture and gun ownership. Gun cultures may need to be considered for public health strategies that aim to change gun ownership in the USA. PMID:26124073

Temporal association between federal gun laws and the diversion of guns to criminals in Milwaukee.

PubMed

Webster, Daniel W; Vernick, Jon S; Bulzacchelli, Maria T; Vittes, Katherine A

2012-02-01

The practices of licensed gun dealers can threaten the safety of urban residents by facilitating the diversion of guns to criminals. In 2003, changes to federal law shielded gun dealers from the release of gun trace data and provided other protections to gun dealers. The 14-month period during which the dealer did not sell junk guns was associated with a 68% reduction in the diversion of guns to criminals within a year of sale by the dealer and a 43% increase in guns diverted to criminals following sales by other dealers. The laws were associated with a 203% increase in the number of guns diverted to criminals within a year of sale by the gun store, which was the focus of this study. Policies which affect gun dealer accountability appeared to influence the diversion of guns to criminals.

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

Thanos, Loukas; Galani, Panagiota, E-mail: paga@hol.gr; Mylona, Sophia

The purpose of this study was to determine the diagnostic value of percutaneous core needle biopsy (CNB) relative to fine needle aspiration (FNA) in patients with pneumonia and pneumonia mimics. In this prospective study we present our experience with 48 thoracic FNAs and CNBs carried out on 48 patients with pneumonia and pneumonia mimics. Samples were obtained from all patients using both CNB (with an automated 18-G core biopsy needle and a gun) and FNA (with a 22-G needle). A specific diagnosis was made in 10/48 cases (20.83%) by FNA and in 42/48 (87.5%) by CNB. The main complications encounteredmore » were pneumothorax (n = 4) and hemoptysis (n = 2), yielding a total complication rate of 12.5%. We concluded that CNB using an automated biopsy gun results in a higher diagnostic accuracy for pneumonia and pneumonia mimic biopsies than FNA. Complications should be considered and proper patient observation should follow the procedure.« less

PASOTRON high-energy microwave source

NASA Astrophysics Data System (ADS)

Goebel, Dan M.; Schumacher, Robert W.; Butler, Jennifer M.; Hyman, Jay, Jr.; Santoru, Joseph; Watkins, Ron M.; Harvey, Robin J.; Dolezal, Franklin A.; Eisenhart, Robert L.; Schneider, Authur J.

1992-04-01

A unique, high-energy microwave source, called PASOTRON (Plasma-Assisted Slow-wave Oscillator), has been developed. The PASOTRON utilizes a long-pulse E-gun and plasma- filled slow-wave structure (SWS) to produce high-energy pulses from a simple, lightweight device that utilizes no externally produced magnetic fields. Long pulses are obtained from a novel E-gun that employs a low-pressure glow discharge to provide a stable, high current- density electron source. The electron accelerator consists of a high-perveance, multi-aperture array. The E-beam is operated in the ion-focused regime where the plasma filling the SWS space-charge neutralizes the beam, and the self-pinch force compresses the beamlets and increases the beam current density. A scale-model PASOTRON, operating as a backward- wave oscillator in C-band with a 100-kV E-beam, has produced output powers in the 3 to 5 MW range and pulse lengths of over 100 microsecond(s) ec, corresponding to an integrated energy per pulse of up to 500 J. The E-beam to microwave-radiation power conversion efficiency is about 20%.

Driving magnetic turbulence using flux ropes in a moderate guide field linear system

NASA Astrophysics Data System (ADS)

Brookhart, Matthew I.; Stemo, Aaron; Waleffe, Roger; Forest, Cary B.

2017-12-01

We present a series of experiments on novel, line-tied plasma geometries as a study of the generation of chaos and turbulence in line-tied systems. Plasma production and the injection scale for magnetic energy is provided by spatially discrete plasma guns that inject both plasma and current. The guns represent a technique for controlling the injection scale of magnetic energy. A two-dimensional (2-D) array of magnetic probes provides spatially resolved time histories of the magnetic fluctuations at a single cross-section of the experimental cylinder, allowing simultaneous spatial measurements of chaotic and turbulent behaviour. The first experiment shows chaotic fluctuations and self-organization in a hollow-current line-tied screw pinch. These dynamics is modulated primarily by the applied magnetic field and weakly by the plasma current and safety factor. The second experiment analyses the interactions of multiple line-tied flux ropes. The flux ropes all exhibit chaotic behaviour, and under certain conditions develop an inverse cascade to larger scales and a turbulent inertial range with magnetic energy ( ) related to perpendicular wave number ( \\bot $ ) as \\bot -2.5\\pm 0.5$ .

Characterization of Flow and Ohm's Law in the Rotating Wall Machine

NASA Astrophysics Data System (ADS)

Hannum, David; Brookhart, M.; Forest, C. B.; Kendrick, R.; Mengin, G.; Paz-Soldan, C.

2010-11-01

The rotating wall machine is a linear screw-pinch built to study the role of different electromagnetic boundary conditions on the Resistive Wall Mode (RWM). Its plasma is created by an array of electrostatic washer guns which can be biased to discharge up to 1 kA of current each. Individual flux ropes from the guns shear, merge, and expand into a 20 cm diameter, ˜1 m long plasma column. Langmuir (singletip) and tri-axial B-dot probes move throughout the column to measure radial and axial profiles of key plasma parameters. As the plasma current increases, more H2 fuel is ionized, raising ne to 5 x10^20 m-3 while Te stays at a constant 3 eV. The electron density expands to the wall while the current density (Jz) stays pinched to the central axis. E xB and diamagnetic drifts create radially and axially sheared plasma rotation. Plasma resistivity follows the Spitzer model in the core while exceeding it at the edge. These measurements improve the model used to predict the RWM growth rate.

Proceedings of the Antenna Applications Symposium (1988) Volume 1

DTIC Science & Technology

1989-06-01

FIELD GROUP SUB-GROUP Antennas)p Microstrip, ,.Multibeam Antennas 6 Satellite Antennas. Reflector Array Antennas, ____________I____ Broadband Antennas...C. Sullivan and G. E. Evans 8. " Broadband MMIC T/R Module/Subarray Performance," D. Brubaker, 157 D. Scott, S. Ludvik, M. Lynch, H. II. Chung, W...34 S. Sanzgiri, 277 B. Powers, Jr., and J. Hart ib. " broadbanding Techniques for Microstrip Patch Antennas - A ’.93 kReview," K. C. Gupta * NUT INCLUDED

Differences Between New and Long-Standing US Gun Owners: Results From a National Survey.

PubMed

Wertz, Joseph; Azrael, Deborah; Hemenway, David; Sorenson, Susan; Miller, Matthew

2018-07-01

To quantify the proportion of current US gun owners who are new to owning firearms and compare new versus long-standing gun owners with respect to their firearms and firearm-related behaviors. We performed a cross-sectional analysis of a nationally representative probability-based online survey conducted in 2015 in the United States. We defined new gun owners as current firearm owners who acquired all of their firearms within the past 5 years, but who lived in a home without a gun at some time over the past 5 years. We defined long-standing firearm owners as all other current gun owners. New gun owners represented 10% of all current US adult gun owners. In addition to being younger than long-standing gun owners, new gun owners were more likely to be liberal, own fewer guns, own handguns, own guns only for protection, and store guns in a safe manner. Gun ownership is dynamic, with approximately 1 million Americans becoming new gun owners each year. Public Health Implications. Clinical guidelines should be updated to explicitly endorse re-evaluating household firearm status at regular intervals.

Flowing Magnetized Plasma experiment

NASA Astrophysics Data System (ADS)

Wang, Zhehui; Si, Jiahe

2006-10-01

Results from the Flowing Magnetized Plasma experiment at Los Alamos are summarized. Plasmas are produced using a modified coaxial plasma gun with a center electrode extending into a cylindrical vacuum tank with 0.75 m in radius and 4.5 m long. The basic diagnostics are Bdot probes for edge and internal magnetic field, Mach probes and Doppler spectroscopy for plasma flow in the axial and azimuthal directions, and Langmuir probes for plasma floating potential, electron density and temperature. We have found two different plasma flow patterns associated with distinct IV characteristics of the coaxial plasma gun, indicating axial flow is strongly correlated with the plasma ejection from the plasma gun. Global electromagnetic oscillations at frequencies below ion cyclotron frequency are observed, indicating that familiar waves at these frequencies, e.g. Alfven wave or drift wave, are strongly modified by the finite plasma beta. We eliminate the possibility of ion sound waves since the ion and electron temperatures are comparable, and therefore, ion sound waves are strongly Landau damped.

Air gun injury with deadly aftermath--case report.

PubMed

Stankov, Aleksandar; Jakovski, Zlatko; Pavlovski, Goran; Muric, Nedzat; Dwork, Andrew J; Cakar, Zdravko

2013-01-01

In Republic of Macedonia the use of air guns is quite widespread. They are used mainly for target practice. They are regulated by the Law of Arms, where they are defined as pneumatic weapons. There is no legal limit on type or quantity of ammunition that one may possess. Our Institute performs at least 90% of the forensic autopsies in Macedonia. In this report we describe the only fatality by pneumatic weapon to come to our attention over the past 10 years. A 6-year-old girl was accidentally wounded by her brother when he and his father were trying a new air gun, a 4.5mm single shot, break barrel, spring piston air rifle manufactured in China under the brand "Westlake". She died within minutes. Autopsy showed cardiac tamponade due to penetration of the aorta. A 0.5g metal projectile, 4.5mm in diameter, with a pointed, conical shape, was recovered from the pericardial sac. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

78 FR 69644 - Certain Steel Nails From the People's Republic of China: Final Results of Expedited First Sunset...

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... 19 CFR 351.218(e)(1)(ii)(C)(2). As explained in the memorandum from the Assistant Secretary for... 21.24 Nanjing Dayu Pneumatic Gun Nails Co., Ltd 21.24 Qidong Liang Chyuan Metal Industry Co., Ltd 21... Co., Ltd 21.24 S-mart (Tianjin) Technology Development Co., Ltd 21.24 Tianjin Lianda Group Co., Ltd...

Results Of Insulation Resistance Between Solar Cell String Gaps Without RTV Adhesive Grout After Electrostatic Discharge Tests With Cover Glass Flashover

NASA Astrophysics Data System (ADS)

Hoang, Bao; Wong, Frankie; Redick, Tod; Masui, Hirokazu; Endo, Taishi; Toyoda, Kazuhiro; Cho, Mengu

2011-10-01

A series of electrostatic discharge (ESD) tests was performed on solar array test coupons consisting of Advanced Triple Junction InGaP2/InGaAs/Ge solar cells. The motivation for these tests was to evaluate the effects of ESD on solar array design without room temperature vulcanized (RTV) adhesive grout between the string-to-string parallel gaps. To investigate the threshold of permanently sustained secondary arcs, various combinations of gap width, load voltage and string current were tested in a vacuum chamber equipped with an electron beam gun. This ESD test program included the ESD test circuit with simulated panel coverglass flashover. Although ESD events did not result in permanent sustained arcs, the insulation resistance between strings was found to decrease as the number of secondary arcs accumulated in the gap.

Field emitter arrays and displays produced by ion tracking lithography

NASA Astrophysics Data System (ADS)

Felter, T. E.; Musket, R. G.; Bernhardt, A. F.

2005-12-01

When ions of sufficient electronic energy loss traverse a dielectric film or foil, they alter the chemical bonding along their nominally straight path within the material. A suitable etchant can quickly dissolve these so-called latent tracks leaving holes of small diameter (∼10 nm) but long length - several microns. Continuing the etching process gradually increases the diameter reproducibly and uniformly. The trackable medium can be applied as a uniform film onto large substrates. The small, monodisperse holes produced by this track etching can be used in conjunction with additional thin film processing to create functional structures attached to the substrate. For example, Lawrence Livermore National Laboratory and Candescent Technologies Corporation (CTC) co-developed a process to make arrays of gated field emitters (∼100 nm diameter electron guns) for CTC's Thin CRTTM displays, which have been fabricated to diagonal dimensions >13 in. Additional technological applications of ion tracking lithography will be briefly covered.

77 FR 37834 - Revocation of Certain Requirements Pertaining to Caps Intended for Use With Toy Guns and Toy Guns...

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2012-06-25

... Certain Requirements Pertaining to Caps Intended for Use With Toy Guns and Toy Guns Not Intended for Use... compliance than our existing regulations pertaining to caps intended for use with toy guns and toy guns not... regulations pertaining to caps intended for use with toy guns and toy guns not intended for use with caps...

Gun Safety (For Kids)

MedlinePlus

... Staying Safe Videos for Educators Search English Español Gun Safety KidsHealth / For Kids / Gun Safety What's in ... from guns outside the home. If You Have Guns in Your Home If your parents keep guns ...

Gun threats against and self-defense gun use by California adolescents.

PubMed

Hemenway, David; Miller, Matthew

2004-04-01

To assess hostile gun use against and self-defense gun use by adolescents. We use random-digit-dial telephone survey data collected from approximately 5800 California adolescents, aged 12 through 17 years, between November 1, 2000, and October 31, 2001. The prevalence and correlates of reported hostile gun use against and self-defense gun use by adolescents, as well as qualitative information about these 2 types of gun uses. Correlates include age, sex, ethnicity, smoking, alcoholic binge drinking, threatening others, parents knowing their adolescent's whereabouts in the afternoon after school, attending school, area urbanization and poverty level, and living in a household with a gun. Approximately 4% of the adolescents reported ever having been threatened with a gun; only 0.3% reported using a gun in self-defense. Boys, smokers, adolescents who threatened others, and adolescents whose parents knew little about their whereabouts in the afternoon after school were more likely to report being threatened with a gun. Most episodes of self-defense gun use seem to be hostile interactions between adolescents with weapons. Far more California adolescents are threatened with a gun than use a gun in self-defense. Self-defense gun use is rare; many of the reported self-defense gun uses seem to be armed confrontations.

Gravity's Smoking Gun?

NASA Astrophysics Data System (ADS)

Gaztañaga, Enrique; Juszkiewicz, Roman

2001-09-01

We present a new constraint on the biased galaxy formation picture. Gravitational instability theory predicts that the two-point mass density correlation function, ξ(r), has an inflection point at the separation r=r0, corresponding to the boundary between the linear and nonlinear regime of clustering, ξ~=1. We show how this feature can be used to constrain the biasing parameter b2≡ξg(r)/ξ(r) on scales r~=r0, where ξg is the galaxy-galaxy correlation function, which is allowed to differ from ξ. We apply our method to real data: the ξg(r), estimated from the Automatic Plate Measuring (APM) galaxy survey. Our results suggest that the APM galaxies trace the mass at separations r>~5 h-1 Mpc, where h is the Hubble constant in units of 100 km s-1 Mpc-1. The present results agree with earlier studies, based on comparing higher order correlations in the APM with weakly nonlinear perturbation theory. Both approaches constrain the b factor to be within 20% of unity. If the existence of the feature that we identified in the APM ξg(r)-the inflection point near ξg=1-is confirmed by more accurate surveys, we may have discovered gravity's smoking gun: the long-awaited ``shoulder'' in ξ, predicted by Gott and Rees 25 years ago.

Compact streak camera for the shock study of solids by using the high-pressure gas gun

NASA Astrophysics Data System (ADS)

Nagayama, Kunihito; Mori, Yasuhito

1993-01-01

For the precise observation of high-speed impact phenomena, a compact high-speed streak camera recording system has been developed. The system consists of a high-pressure gas gun, a streak camera, and a long-pulse dye laser. The gas gun installed in our laboratory has a muzzle of 40 mm in diameter, and a launch tube of 2 m long. Projectile velocity is measured by the laser beam cut method. The gun is capable of accelerating a 27 g projectile up to 500 m/s, if helium gas is used as a driver. The system has been designed on the principal idea that the precise optical measurement methods developed in other areas of research can be applied to the gun study. The streak camera is 300 mm in diameter, with a rectangular rotating mirror which is driven by an air turbine spindle. The attainable streak velocity is 3 mm/microsecond(s) . The size of the camera is rather small aiming at the portability and economy. Therefore, the streak velocity is relatively slower than the fast cameras, but it is possible to use low-sensitivity but high-resolution film as a recording medium. We have also constructed a pulsed dye laser of 25 - 30 microsecond(s) in duration. The laser can be used as a light source of observation. The advantage for the use of the laser will be multi-fold, i.e., good directivity, almost single frequency, and so on. The feasibility of the system has been demonstrated by performing several experiments.

Guns and Violence. Current Controversies.

ERIC Educational Resources Information Center

Kim, Henny H., Ed.

This book focuses on gun violence and gun control, presenting both sides of arguments about firearms ownership and gun control. Each of five chapters poses a question about gun control and provides answers for both sides of the question. The following essays are included: (1) "Gun Violence Is Becoming an Epidemic" (Bob Herbert); (2) "Gun Violence…

Gun Control, Gun Ownership, and Suicide Prevention.

ERIC Educational Resources Information Center

Lester, David

1988-01-01

Explored relationship between the extent of gun ownership and the strictness of gun control laws to suicide and homicide rates in the nine major geographic regions of the United States. Found gun ownership, rather than the strictness of gun control laws, was the strongest correlate of the rates of suicide and homicide by guns. (Author)

Gun ownership and social gun culture.

PubMed

Kalesan, Bindu; Villarreal, Marcos D; Keyes, Katherine M; Galea, Sandro

2016-06-01

We assessed gun ownership rates in 2013 across the USA and the association between exposure to a social gun culture and gun ownership. We used data from a nationally representative sample of 4000 US adults, from 50 states and District of Columbia, aged >18 years to assess gun ownership and social gun culture performed in October 2013. State-level firearm policy information was obtained from the Brady Law Center and Injury Prevention and Control Center. One-third of Americans reported owning a gun, ranging from 5.2% in Delaware to 61.7% in Alaska. Gun ownership was 2.25-times greater among those reporting social gun culture (PR=2.25, 95% CI 2.02 to 2.52) than those who did not. In conclusion, we found strong association between social gun culture and gun ownership. Gun cultures may need to be considered for public health strategies that aim to change gun ownership in the USA. 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/

X-ray emission from high temperature plasmas

NASA Technical Reports Server (NTRS)

Harries, W. L.

1977-01-01

The physical processes occurring in plasma focus devices were investigated with particular emphasis on X-ray emission. Topics discussed include: trajectories of high energy electrons; detection of ion trajectories; spatial distribution of neutron emission; space and time resolved emission of hard X-rays from a plasma focus; the staged plasma focus as a variation of the hypocloidal pinch; formation of current sheets in a staged plasma focus; and X-ray and neutron emission from a staged plasma focus. The possibility of operating dense plasma-focus type devices in multiple arrays beyond the scaling law for a single gun is discussed.

Surface-plasmon enhanced photoemission of a silver nano-patterned photocathode

NASA Astrophysics Data System (ADS)

Zhang, Z.; Li, R.; To, H.; Andonian, G.; Pirez, E.; Meade, D.; Maxson, J.; Musumeci, P.

2017-09-01

Nano-patterned photocathodes (NPC) take advantage of plasmonic effects to resonantly increase absorption of light and localize electromagnetic field intensity on metal surfaces leading to surface-plasmon enhanced photoemission. In this paper, we report the status of NPC research at UCLA including in particular the optimization of the dimensions of a nanohole array on a silver wafer to enhance plasmonic response at 800 nm light, the development of a spectrally-resolved reflectivity measurement setup for quick nanopattern validation, and of a novel cathode plug to enable high power tests of NPCs on single crystal substrates in a high gradient radiofrequency gun.

Experimental determination of drag coefficients in low-density polyurethane foam

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

Adams, M L

2006-04-18

We describe several experiments performed at the LLNL Site 300 firing range and on the LLNL 1/3 scale gun to investigate the deceleration of small projectiles (l {approx} 3-5 [mm]) in low-density foam ({rho} {approx} 0.08-0.32 [g/cm{sup 3}]). The experiments at the firing range researched a passive velocity diagnostic based on Faraday's law of induction, while experiments on the 1/3 scale gun investigated the effects of varying projectile surface area, projectile shape, and foam density on the drag coefficient c{sub d}. Analysis shows that the velocity diagnostic has an uncertainty on the order of 1 percent for projectiles with velocitymore » v {approx} 0.8-1.2 [km/s]. The 1/3 scale gun experiments, dubbed the Krispy Kreme series, included nine shots considering the combinations of 3 projectile surface areas with 3 target densities. The experiments used Tantalum square surface area block projectiles (with an initial velocity v{sub 0} {approx} 1.2 [km/s], a common thickness T = 2.67 [mm], and square side lengths of 3, 4, and 5 [mm]) decelerating in polyurethane foams (with densities {rho}{sub f} of 0.08, 0.16 and 0.32 [g/cm{sup 3}]). Standard fluid models of the Krispy Kreme experiments predict Reynolds numbers Re {approx} 10{sup 5} - 10{sup 6}, Mach numbers Ma {approx} 0.5-2.0, and drag coefficients c{sub d} {approx} 2-3. However, the data indicate that c{sub d} = 1.1-1.2 (c{sub d} = 1.7) for all three block projectiles in the 0.08 and 0.16 [g/cm{sup 3}] targets (0.32 [g/cm{sup 3}] target). First, we conclude that the drag force on projectiles in solid polyurethane foam is less than in fluids with equivalent dimensionless parameters. This result is also supported by an additional Krispy Kreme experiment that used a disk projectile (with diameter d = 4.51 [mm] and thickness T = 2.67 [mm]) penetrating a target with density {rho} = 0.16 [g/cm{sup 3}], i.e., the fluid-like c{sub d} = 1.15 while the measured c{sub d} = 0.63. Second, we conclude that the measured drag coefficient in the lower density foam targets is less than in the larger density foam target. This result is corroborated by firing range experiments with M855 NATO bullets (with diameter 5.56 [mm], mass 4.1 [g], and initial velocity {nu}{sub 0} {approx} 800 [m/s]) fired from an M16 rifle, i.e., c{sub d} = 0.3 (c{sub d} = 0.6) in the 0.16 [g/cm{sup 3}] (0.32 [g/cm{sup 3}]) target. We propose future 1/3 scale gun experiments using a passive velocity diagnostic with increased spatial resolution as well as simple spherical projectiles with 0.5 and 1.0 [cm] diameters.« less

Wide-angle seismic recordings from the 1998 Seismic Hazards Investigation of Puget Sound (SHIPS), western Washington and British Columbia

USGS Publications Warehouse

Brocher, Thomas M.; Parsons, Tom; Creager, Ken C.; Crosson, Robert S.; Symons, Neill P.; Spence, George D.; Zelt, Barry C.; Hammer, Philip T.C.; Hyndman, Roy D.; Mosher, David C.; Tréhu, Anne M.; Miller, Kate C.; ten Brink, Uri S.; Fisher, Michael A.; Pratt, Thomas L.; Alvarez, Marcos G.; Beaudoin, Bruce C.; Louden, Keith E.; Weaver, Craig S.

1999-01-01

This report describes the acquisition and processing of deep-crustal wide-angle seismic reflection and refraction data obtained in the vicinity of Puget Lowland, the Strait of Juan de Fuca, and Georgia Strait, western Washington and southwestern British Columbia, in March 1998 during the Seismic Hazards Investigation of Puget Sound (SHIPS). As part of a larger initiative to better understand lateral variations in crustal structure along the Cascadia margin, SHIPS participants acquired 1000 km of deep-crustal multichannel seismic-reflection profiles and 1300 km of wideangle airgun shot lines in this region using the R/V Thompson and R/V Tully. The Tully was used to record airgun shots fired by the Thompson in two different geometries: (1) expanding spread profiles (ESPs) and (2) constant offset profiles (COPs). Prior to this reflection survey, we deployed 257 Reftek and 15 ocean-bottom seismic recorders to record the airgun signals at far offsets. All data were recorded digitally on large-capacity hard disks. Although most of these stations only recorded the vertical component of motion, 95 of these seismographs recorded signals from an oriented 3-component seismometer. By recording signals generated by the Thompson's marine air gun array, operated in two differing geometries having a total volume of 110 and 79 liters (6730 and 4838 cu. in.), respectively, the arrays of wide-angle recorders were designed to (1) image the crustal structure, particularly in the vicinity of crustal faults and Cenozoic sedimentary basins, (2) determine the geometry of the Moho, and (3) image the subducting Gorda and Juan de Fuca plates. Nearly 33,300 air gun shots were recorded along several seismic lines. In this report, we illustrate the expanding spread profiles acquired using the Thompson and Tully, describe the land and ocean-bottom recording of the air gun signals, discuss the processing of the land recorder data into common receiver gathers, and illustrate the processed wide-angle seismic data collected using the Refteks and ocean-bottom seismometers. We also describe the format and content of the archival tapes containing the SEGY-formated, common-receiver gathers for the Reftek data. Data quality is variable but SHIPS appears to have successfully obtained useful data from almost all the stations deployed to record the airgun shots. Several interesting arrivals were observed: including refractions from the sedimentary basin fill in several basins, refractions from basement rocks forming the upper crust, Pg, refractions from the upper mantle, Pn, as well as reflections from within the crust and from the top of the upper mantle, PmP. We separately archived more than 30 local earthquakes recorded by the Reftek array during our deployment.

Biolistic transfection of neuronal cultures using a hand-held gene gun

PubMed Central

O'Brien, John A; Lummis, Sarah C R

2009-01-01

Biolistic transfection is a technique in which subcellular-sized particles coated with DNA are accelerated to high velocity to propel them into cells. This method is applicable to tissues, cells and organelles, and can be used for both in vitro and in vivo transformations; with the right equipment, it is simple, rapid and efficient. Here we provide a detailed protocol for biolistic transfection of plasmids into cultured human embryonic kidney (HEK) 293 cells and organotypic brain slices using a hand-held gene gun. There are three major steps: (i) coating microcarriers with DNA, (ii) transferring the microcarriers into a cartridge to make a ‘bullet’, and (iii) firing the DNA-coated microcarriers into cells using a pulse of helium gas. The method can be readily adapted to other cell types and tissues. The protocol can be completed in 1–2 h. PMID:17406333

123. FORWARD PORT VIEW OF THE ISLAND WITH FLIGHT DECK ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

123. FORWARD PORT VIEW OF THE ISLAND WITH FLIGHT DECK GUN MOUNTS, TAKEN FROM FORWARD FLIGHT DECK. APRIL 1945, (NATIONAL ARCHIVES NO. 80-G-469299) - U.S.S. HORNET, Puget Sound Naval Shipyard, Sinclair Inlet, Bremerton, Kitsap County, WA

Effects of two ergonomic improvements in brazing coils of air-handler units.

PubMed

Loo, H S; Yeow, Paul H P

2015-11-01

The research aims to address the physically loading task and quality and productivity problems in the brazing of coils of air-handler units. Eight operators participated in two intervention studies conducted in a factory in Malaysia to compare the status quo brazing with (1) the use of a new twin-brazing torch that replaced the single-brazing gun and (2) brazing in a sitting position. The outcome measures are related to quality, productivity, monetary costs, body postures and symptoms. After baseline, Interventions I and II were applied for 3 months respectively. The results show a 58.9% quality improvement, 140% productivity increase and 113 times ROI. There was also a reduction in poor work postures e.g. in the raising of the arms and shoulders; bending, twisting and extending of the neck; and bending of left and right wrists, and the back. This research can be replicated in other factories that share similar processes. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Where the guns come from: the gun industry and gun commerce.

PubMed

Wintemute, Garen J

2002-01-01

Under federal law, it is illegal for youth under age 18 to purchase rifles or shotguns, and for those under age 21 to purchase handguns. However, fatality and injury statistics clearly show that guns are finding their way into young people's hands. Many of these youth obtain guns through illegal gun markets. This article focuses on how guns in the United States are manufactured, marketed, and sold. The article shows how the legal and illegal gun markets are intimately connected and make guns easily accessible to youth. Although the domestic gun manufacturing industry is relatively small and has experienced declining sales in recent years, it has significant political clout and a large market for its products, and has engaged in aggressive marketing to youth. Lax oversight of licensed firearms dealers, combined with little or no regulation of private sales between gun owners, mean that guns can quickly moved from the legal gun market into the illegal market, where they can be acquired by young people. Certain guns, especially inexpensive, poorly made small handguns, are particularly attractive to criminals and youth. The author observes that several policy innovations--including increased regulation of licensed firearms dealers, intensified screening of prospective buyers, regulation of private sales, gun licensing and registration, and bans on some types of weapons--hold promise for decreasing the flow of guns into the hands of youth.

Effects of a Gun Dealer's Change in Sales Practices on the Supply of Guns to Criminals

PubMed Central

Vernick, Jon S.; Bulzacchelli, Maria T.

2006-01-01

Licensed gun dealers are a major conduit for gun trafficking. Prior to May 1999, a single gun store sold more than half of the guns recovered from criminals in Milwaukee, WI, shortly following retail sale. On May 10, 1999, the store stopped selling small, inexpensive handguns popular with criminals, often called “Saturday night specials.” The purpose of this study was to estimate the effect of this gun store's changed sales practices on criminals' acquisition of new guns. We used an interrupted time-series design with comparisons to test for changes in the number of guns that police recovered from criminals within a year of retail sale following the gun dealer's new sales policy. The dealer's changed sales policy was associated with a 96% decrease in recently sold, small, inexpensive handguns use in crime in Milwaukee, a 73% decrease in crime guns recently sold by this dealer, and a 44% decrease in the flow of all new, trafficked guns to criminals in Milwaukee. The findings demonstrate the substantial impact that a single gun store's sales practices can have on the supply of new guns to criminals. Proposed anti-gun-trafficking efforts in other cities could benefit from targeting problem retail outlets. PMID:16937085

Effects of Exposure to Gun Violence in Movies on Children's Interest in Real Guns.

PubMed

Dillon, Kelly P; Bushman, Brad J

2017-11-01

More US children die by accidental gun use than children in other developed countries. One factor that can influence children's interest in guns is exposure to media containing guns. To test whether children who see a movie containing guns will handle a real gun longer and will pull the trigger more times than children who see the same movie not containing guns. One hundred four children aged 8 to 12 years recruited through advertisements were randomly assigned in pairs to watch a 20-minute PG-rated movie containing or not containing guns in a university laboratory. Children then played with toys and games in a room for 20 minutes while being video recorded. A cabinet in the room contained a real (disabled) gun with a sensor counting trigger pulls. Recordings were coded for the time spent holding the gun and in aggressive play. Data were collected from July 15, 2015, through January 1, 2016, and analyzed using generalized estimating equations (Tweedie log-link for time spent holding the gun; Poisson log-link for pulling the trigger). The 2 main outcomes were time spent holding the gun and the number of trigger pulls. Control variables included sex, age, trait aggressiveness, exposure to violent media, interest in guns, and number of guns at home. Among the 104 study participants (62 boys [59.6%] and 42 girls [40.4%]; mean (SD) age, 9.9 [1.5] years), the adjusted median number of trigger pulls among children who saw the movie containing guns was 2.8 (interquartile range [IQR], 0.2-2.8) compared with 0.01 (IQR, 0.01-0.2) among children who saw the movie not containing guns (adjusted odds ratio, 22.3; 95% CI, 6.0-83.4; P < .001). The adjusted median number of seconds spent holding the gun among children who saw a movie containing guns was 53.1 (IQR, 35.5-53.1) compared with 11.1 (IQR, 10.7-16.7) among children who saw the movie not containing guns (adjusted odds ratio, 3.0; 95% CI, 0.9-9.9; P = .07). Qualitative analyses on 4 pairs from each condition found that children who saw the movie containing guns also played more aggressively and sometimes fired the gun at people (ie, self, partner, or passersby on street). Children in the United States frequently have access to unsecured firearms and frequently consume media containing guns. This experiment shows that children who see movie characters use guns are more likely to use guns themselves. clinicaltrials.gov Identifier NCT03220412.

Transformation of a Virgo Cluster dwarf irregular galaxy by ram pressure stripping: IC3418 and its fireballs

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

Kenney, Jeffrey D. P.; Geha, Marla; Jáchym, Pavel

We present optical imaging and spectroscopy and H I imaging of the Virgo Cluster galaxy IC 3418, which is likely a 'smoking gun' example of the transformation of a dwarf irregular into a dwarf elliptical galaxy by ram pressure stripping. IC 3418 has a spectacular 17 kpc length UV-bright tail comprised of knots, head-tail, and linear stellar features. The only Hα emission arises from a few H II regions in the tail, the brightest of which are at the heads of head-tail UV sources whose tails point toward the galaxy ('fireballs'). Several of the elongated tail sources have Hα peaksmore » outwardly offset by ∼80-150 pc from the UV peaks, suggesting that gas clumps continue to accelerate through ram pressure, leaving behind streams of newly formed stars which have decoupled from the gas. Absorption line strengths, measured from Keck DEIMOS spectra, together with UV colors, show star formation stopped 300 ± 100 Myr ago in the main body, and a strong starburst occurred prior to quenching. While neither Hα nor H I emission are detected in the main body of the galaxy, we have detected 4 × 10{sup 7} M {sub ☉} of H I from the tail with the Very Large Array. The velocities of tail H II regions, measured from Keck LRIS spectra, extend only a small fraction of the way to the cluster velocity, suggesting that star formation does not happen in more distant parts of the tail. Stars in the outer tail have velocities exceeding the escape speed, but some in the inner tail should fall back into the galaxy, forming halo streams.« less

Microparticle impact calibration of the Arrayed Large-Area Dust Detectors in INterplanetary space (ALADDIN) onboard the solar power sail demonstrator IKAROS

NASA Astrophysics Data System (ADS)

Hirai, Takayuki; Cole, Michael J.; Fujii, Masayuki; Hasegawa, Sunao; Iwai, Takeo; Kobayashi, Masanori; Srama, Ralf; Yano, Hajime

2014-10-01

The Arrayed Large-Area Dust Detectors in INterplanetary space (ALADDIN) is an array of polyvinylidene fluoride (PVDF) based dust detectors aboard the solar power sail demonstrator named IKAROS (Interplanetary Kite-craft Accelerated by Radiation Of the Sun). The total sensor area of ALADDIN (0.54 m2) is the world's largest among the past PVDF-based dust detectors. IKAROS was launched in May 2010 and then ALADDIN measured cosmic dust impacts for 16 months while orbiting around between 0.7 and 1.1 AU. The main scientific objective of ALADDIN is to reveal number density of ≥10-μm-sized dust in the zodiacal cloud with much higher time-space resolution than that achieved by any past in-situ measurements. The distribution of ≥10-μm-sized dust can be also observed mainly with the light scattering by optical instruments. This paper gives the scientific objectives, the instrumental description, and the results of microparticle impact calibration of ALADDIN conducted in ground laboratories. For the calibration tests we used Van de Graaf accelerators (VdG), two-stage light gas guns (LGG), and a nano-second pulsed Nd:YAG laser (nsPL). Through these experiments, we obtained depolarization charge signal caused by hypervelocity impacts or laser irradiation using the flight spare of 20-μm-thick PVDF sensor and the electronics box of ALADDIN. In the VdG experiment we accelerated iron, carbon, and silver microparticles at 1-30 km/s, while in the LGG experiment we performed to shoot 100's-μm-sized particles of soda-lime glass and stainless steel at 3-7 km/s as single projectile. For interpolation to ≥10-μm size, we irradiated infrared laser at the energy of 15-20 mJ directly onto the PVDF sensor. From the signal analysis, we developed a calibration law for estimation of masses of impacted dust particles. The dynamic range of ALADDIN corresponds from 9×10-14 kg to 2×10-10 kg (4-56 μm in diameter at density of 2.0 g/cm3) at the expected impact velocity of 10 km/s at 1 AU on the IKAROS inbound orbit. It was found that ALADDIN has ability to measure spatial densities of interplanetary dust particles larger than 10 μm in size by setting the sensor threshold to an output voltage of 1 V.

The impact of the Orlando mass shooting on fear of victimization and gun-purchasing intentions: Not what one might expect.

PubMed

Stroebe, Wolfgang; Leander, N Pontus; Kruglanski, Arie W

2017-01-01

Mass public shootings are typically followed by a spike in gun sales as well as calls for stricter gun control laws. What remains unclear is whether the spike in gun sales is motivated by increased threat perceptions or by concerns about gun control, or whether the sales are mainly driven by non-owners purchasing guns or gun owners adding to their collection. Two surveys of gun owners and non-owners, conducted immediately before and after the Orlando shooting, allowed us to assess its impact on threat perceptions and on gun-purchasing intentions. Although there was a minor impact on threat perceptions of non-owners, neither group reported any increased gun-purchasing intentions or an increased need of a gun for protection and self-defense. We suggest that these responses are representative for the majority of Americans and, therefore, people who are influenced by mass shootings to buy guns are probably an atypical minority.

The impact of the Orlando mass shooting on fear of victimization and gun-purchasing intentions: Not what one might expect

PubMed Central

Stroebe, Wolfgang; Leander, N. Pontus; Kruglanski, Arie W.

2017-01-01

Mass public shootings are typically followed by a spike in gun sales as well as calls for stricter gun control laws. What remains unclear is whether the spike in gun sales is motivated by increased threat perceptions or by concerns about gun control, or whether the sales are mainly driven by non-owners purchasing guns or gun owners adding to their collection. Two surveys of gun owners and non-owners, conducted immediately before and after the Orlando shooting, allowed us to assess its impact on threat perceptions and on gun-purchasing intentions. Although there was a minor impact on threat perceptions of non-owners, neither group reported any increased gun-purchasing intentions or an increased need of a gun for protection and self-defense. We suggest that these responses are representative for the majority of Americans and, therefore, people who are influenced by mass shootings to buy guns are probably an atypical minority. PMID:28800365

Interpreting the empirical evidence on illegal gun market dynamics.

PubMed

Braga, Anthony A; Wintemute, Garen J; Pierce, Glenn L; Cook, Philip J; Ridgeway, Greg

2012-10-01

Thousands of Americans are killed by gunfire each year, and hundreds of thousands more are injured or threatened with guns in robberies and assaults. The burden of gun violence in urban areas is particularly high. Critics suggest that the results of firearm trace data and gun trafficking investigation studies cannot be used to understand the illegal supply of guns to criminals and, therefore, that regulatory and enforcement efforts designed to disrupt illegal firearms markets are futile in addressing criminal access to firearms. In this paper, we present new data to address three key arguments used by skeptics to undermine research on illegal gun market dynamics. We find that criminals rely upon a diverse set of illegal diversion pathways to acquire guns, gun traffickers usually divert small numbers of guns, newer guns are diverted through close-to-retail diversions from legal firearms commerce, and that a diverse set of gun trafficking indicators are needed to identify and shut down gun trafficking pathways.

Development of spray guns for the application of rigid foam insulation

NASA Technical Reports Server (NTRS)

Allen, Peter B.

1993-01-01

The paper describes the activities initiated to improve the existing spray gun system used for spraying insulating foam on the External Tank of the Space Shuttle, due to the quality variations of the applied foam noted in the past. Consideration is given to the two tasks of the project: (1) investigations of possible improvements, as an interim measure, to the spray gun currently used to apply the large acreage spray-on-foam insulation and the evaluation of other commercial equipment; and (2) the design and fabrication of a new automatic spray gun. The design and operation of the currently used Binks 43 PA spray gun are described together with several new breadboard spray guns designed and fabricated and the testing procedures developed. These new guns include the Modular Automatic Foam spray gun, the Ball Valve spray gun, and the Tapered Plug Valve (TPV) gun. As a result of tests, the TPV spray gun is recommended to replace the currently used automatic spray gun.

Unintended Relevance: The Role of the Stryker Brigade Combat Team in the Decisive Action Environment

DTIC Science & Technology

2017-05-25

Systems , 30MM 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a. NAME OF RESPONSIBLE PERSON Walter C. Gray II...Facilities- Policy FCS Future Combat System FM Field Manual FMTV Family of Medium Tactical Vehicles GCV Ground Combat Vehicle GWOT...Vehicle MGS Mobile Gun System MPF Mobile Protected Firepower NATO North Atlantic Treaty Organization ONS Operational Needs Statement RPG

78 FR 66840 - Revocation of Certain Requirements Pertaining to Caps Intended for Use With Toy Guns and Toy Guns...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-07

... Certain Requirements Pertaining to Caps Intended for Use With Toy Guns and Toy Guns Not Intended for Use... regulations pertaining to caps intended for use with toy guns refer to obsolete equipment, but the ASTM F963... revokes the existing regulations pertaining to caps intended for use with toy guns and toy guns not...

Novel Antigen Identification Method for Discovery of Protective Malaria Antigens by Rapid Testing of DNA Vaccines Encoding Exons from the Parasite Genome

DTIC Science & Technology

2004-03-01

EAA21673 1,443 — — Xeroderma pigmentosum G N&I region, helix-hairpin-helix class P.f., P.k., P.b., P.v. PY02286 EAA21722 696 — — Hypothetical protein...ND PY01828 Gene gun 0.1 2,560 640 Pos IM 0.1 Neg Neg ND CSP Gene gun 0.1 2,560 Neg Neg IM 2.7* 2,560 Neg ND a Parasite burden in liver is in...negative; Pos , positive; ND, not done. c Sera tested at a single dilution (1:80). VOL. 72, 2004 DISCOVERY OF PROTECTIVE MALARIA PARASITE ANTIGENS 1599

126. AERIAL FORWARD VIEW OF ENCLOSED HURRICANE BOW WITH FLIGHT ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

126. AERIAL FORWARD VIEW OF ENCLOSED HURRICANE BOW WITH FLIGHT DECK GUN MOUNTS REMOVED AND ANGLED FLIGHT DECK. 1 OCTOBER 1956. (NATIONAL ARCHIVES NO. 80-G-1001445) - U.S.S. HORNET, Puget Sound Naval Shipyard, Sinclair Inlet, Bremerton, Kitsap County, WA

Characteristics of a gun exchange program, and an assessment of potential benefits

PubMed Central

Romero, M.; Wintemute, G.; Vernick, J.

1998-01-01

Objectives—To describe a gun exchange program and assess potential benefits for participants and host communities. Methods—Mail survey of participants in a Sacramento, California gun exchange program, August 1993; the response rate was 79%. Comparative data were obtained from nationwide polls of gun owners. Results—Most (62%) respondents were men; 40% were more than 55 years old; none was less than 25. Concern that children might find and use the gun was the most frequently cited reason for participating (46% of respondents). Of 141 firearms exchanged, 72% were handguns; 23% of respondents indicated that the guns they turned in were not in working order. Of respondents who owned a gun at the time of the program (rather than those who owned no guns and turned in a gun owned by someone else), 41% owned no guns after participating; the prevalence of handgun ownership declined from 79% to 32%. Those who continued to own guns were as likely as gun owners nationwide to keep a gun loaded in the house (odds ratio (OR) 0.9, 95% confidence interval (CI) 0.4 to 1.7) or to carry a gun with them (OR 1.5, 95% CI 0.6 to 3.8). Conclusions—Gun exchange programs may reduce risk for firearm violence among some participants, but a number of factors limit their overall benefits to host communities. PMID:9788092

Large Bore Powder Gun Qualification (U)

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

Rabern, Donald A.; Valdiviez, Robert

A Large Bore Powder Gun (LBPG) is being designed to enable experimentalists to characterize material behavior outside the capabilities of the NNSS JASPER and LANL TA-55 PF-4 guns. The combination of these three guns will create a capability to conduct impact experiments over a wide range of pressures and shock profiles. The Large Bore Powder Gun will be fielded at the Nevada National Security Site (NNSS) U1a Complex. The Complex is nearly 1000 ft below ground with dedicated drifts for testing, instrumentation, and post-shot entombment. To ensure the reliability, safety, and performance of the LBPG, a qualification plan has beenmore » established and documented here. Requirements for the LBPG have been established and documented in WE-14-TR-0065 U A, Large Bore Powder Gun Customer Requirements. The document includes the requirements for the physics experiments, the gun and confinement systems, and operations at NNSS. A detailed description of the requirements is established in that document and is referred to and quoted throughout this document. Two Gun and Confinement Systems will be fielded. The Prototype Gun will be used primarily to characterize the gun and confinement performance and be the primary platform for qualification actions. This gun will also be used to investigate and qualify target and diagnostic modifications through the life of the program (U1a.104 Drift). An identical gun, the Physics Gun, will be fielded for confirmatory and Pu experiments (U1a.102D Drift). Both guns will be qualified for operation. The Gun and Confinement System design will be qualified through analysis, inspection, and testing using the Prototype Gun for the majority of process. The Physics Gun will be qualified through inspection and a limited number of qualification tests to ensure performance and behavior equivalent to the Prototype gun. Figure 1.1 shows the partial configuration of U1a and the locations of the Prototype and Physics Gun/Confinement Systems.« less

Gun Play

ERIC Educational Resources Information Center

Mechling, Jay

2008-01-01

Biology and the particular gun culture of the United States come together to explain the persistent and powerful attraction of American boys to both real guns and toy guns. The 1990s saw adults begin to conflate "the gun problem" with "the boy problem," sparking attempts (largely failed) to banish toy guns from homes and…

Gun Attitudes and Fear of Crime.

ERIC Educational Resources Information Center

Heath, Linda; Weeks, Kyle; Murphy, Marie Mackay

1997-01-01

Using three studies, examined the relationship between attitudes toward guns and fear of crime. Findings indicate a connection between fear of crime and attitudes toward guns: people higher in fear of crime favored gun control. Results also established a relationship between stereotypical beliefs about gun victims and support for gun control. (RJM)

Gun shows across a multistate American gun market: observational evidence of the effects of regulatory policies.

PubMed

Wintemute, Garen J

2007-06-01

To describe gun shows and assess the impact of increased regulation on characteristics linked to their importance as sources of guns used in crime. Cross-sectional, observational. Data were collected at a structured sample of 28 gun shows in California, which regulates these events and prohibits undocumented private party gun sales; and in Arizona, Nevada, Texas and Florida-all leading sources of California's crime guns--where these restrictions do not exist. Size of shows, measured by numbers of gun vendors and people in attendance; number and nature of guns for sale by gun vendors; measures of private party gun sales and illegal surrogate ("straw") gun purchases. Shows in comparison states were larger, but the number of attendees per gun vendor was higher in California. None of these differences was statistically significant. Armed attendees were more common in other states (median 5.7%, interquartile range (IQR) 3.9-10.0%) than in California (median 1.1%, IQR 0.5-2.2%), p = 0.0007. Thirty percent of gun vendors both in California and elsewhere were identifiable as licensed firearm retailers. There were few differences in the types or numbers of guns offered for sale; vendors elsewhere were more likely to sell assault weapons (34.9% and 13.3%, respectively; p = 0.001). Straw purchases were more common in the comparison states (rate ratio 6.6 (95% CI 0.9 to 49.1), p = 0.06). California's regulatory policies were associated with a decreased incidence of anonymous, undocumented gun sales and illegal straw purchases at gun shows. No significant adverse effects of these policies were observed.

Frequency of Guns in the Households of High School Seniors*

PubMed Central

Coker, Ann L.; Bush, Heather M.; Follingstad, Diane R.; Brancato, Candace J.

2017-01-01

BACKGROUND In 2013, President Obama lifted the federal ban on gun violence research. The current study provides one of the first reports to estimate household gun ownership as reported by youth. METHODS In this cohort study of 3006 high school seniors from 24 schools, we examined the frequency of household guns ownership. RESULTS About 65% reported having at least 1 gun in their household. White males were more likely to have a gun and to have more guns than other demographically characterized groups. After adjustment for race and sex, those of higher income, who lived in suburban or rural areas, identified as being exclusively attracted to the opposite sex, and in a romantic relationship, were more likely to have a gun in their household. Having a gun was not associated with increasing symptoms of depression or current poor physical or mental health. CONCLUSIONS Whereas we cannot determine gun types or reasons for having a gun, this research indicates that high school seniors are aware of and may have access to guns for use other than their intended purpose. Household gun ownership among students at higher risk for violence may pose safety challenges for communities and schools. PMID:28147456

Frequency of Guns in the Households of High School Seniors.

PubMed

Coker, Ann L; Bush, Heather M; Follingstad, Diane R; Brancato, Candace J

2017-03-01

In 2013, President Obama lifted the federal ban on gun violence research. The current study provides one of the first reports to estimate household gun ownership as reported by youth. In this cohort study of 3006 high school seniors from 24 schools, we examined the frequency of household guns ownership. About 65% reported having at least 1 gun in their household. White males were more likely to have a gun and to have more guns than other demographically characterized groups. After adjustment for race and sex, those of higher income, who lived in suburban or rural areas, identified as being exclusively attracted to the opposite sex, and in a romantic relationship, were more likely to have a gun in their household. Having a gun was not associated with increasing symptoms of depression or current poor physical or mental health. Whereas we cannot determine gun types or reasons for having a gun, this research indicates that high school seniors are aware of and may have access to guns for use other than their intended purpose. Household gun ownership among students at higher risk for violence may pose safety challenges for communities and schools. © 2017, American School Health Association.

Theoretical Modeling of the Interior Ballistics of the Electrothermal Gun

DTIC Science & Technology

1993-07-01

latter one 19 Table 2.1 Parameters Used for Nominal Data Base (after Oberle [2]). Chamber Volume 97.108 cm 3 Projectile Travel 145 cm Bore Diameter 14...at the time when the plasma supply is completed. When this occurs in the case of instantaneous mixing one has the projectile travel reduced by... Travel 400.0 cm Bore Diameter 4.0 cm Projectile Hass 160 g Plasma Energy 2000000 J Plasma Mass 0.0 g Working Fluid 420 g of H20 Density I g/cm. Bulk

Shooting rampages, mental health, and the sensationalization of violence

PubMed Central

Faria, Miguel A.

2013-01-01

Gun violence and, most recently, senseless shooting rampages continue to be sensitive and emotional points of debate in the American media and the political establishment. The United Nations is already set to commence discussing and approving its Small Arms Treaty in March 2013. And following the Newtown, Connecticut tragedy in the United States this past December, American legislators are working frantically to pass more stringent gun control laws in the U.S. Congress. The American media and proponents of gun control assert that the problem lies in the “easy availability of guns” and “too many guns” in the hand of the public. Second Amendment and gun rights advocates, on the other hand, believe the problem lies elsewhere, including a permissive criminal justice system that panders to criminals; the failure of public education; the fostering of a culture of dependence, violence, and alienation engendered by the welfare state; and the increased secularization of society with children and adolescents growing up devoid of moral guidance. I cannot disagree with the latter view, but I believe there are additional, contributing, and more proximate causes — e.g., failures of the mental health system and the role of the media and popular culture in the sensationalization of violence — that also need to be specifically pointed out and discussed in the medical literature, as I have set out to do in this review article. PMID:23493715

Women and Guns. Firearm Facts.

ERIC Educational Resources Information Center

Duker, Laurie, Ed.

Many gun manufacturers market guns to women claiming a gun can provide protection. Statistics provided in this fact sheet indicate gun ownership may provide a false sense of security that can be fatal, since the greatest threat to a woman comes from the people and guns within her own home. Contrary to "typical" scenarios created by advertisers,…

Physicians Asking Patients About Guns: Promoting Patient Safety, Respecting Patient Rights.

PubMed

Parent, Brendan

2016-10-01

Recent debate on whether physicians should discuss gun ownership with their patients has centered on determining whether gun injuries are an issue of health or safety, and on protecting patient privacy. Yet, physicians' duties span personal health, public health, and safety spheres, and they often must address private patient matters. To prioritize gun safety and reduce gun injuries, the primary policy-driving question should be: will physician counseling on gun ownership effectively reduce gun-related injuries without interfering with the physician's other treatment obligations or compromising the physician-patient relationship? Existing data on physician-initiated conversations with patients about guns support a positive prevention effect. However, it is critical that physician-initiated discussions of safe gun practices are not motivated by, nor convey, disapproval of gun ownership. To be ethical, respectful, and efficient, the conversation should be standard between primary care providers and all of their patients (not limited to patient subsets); questions and education should be limited to topics of gun-ownership risks and storage practices; and the conversation must be framed without bias against gun ownership.

Multichannel seismic-reflection profiling on the R/V Maurice Ewing during the Los Angeles Region Seismic Experiment (LARSE), California

USGS Publications Warehouse

Brocher, Thomas M.; Clayton, Robert W.; Klitgord, Kim D.; Bohannon, Robert G.; Sliter, Ray; McRaney, John K.; Gardner, James V.; Keene, J.B.

1995-01-01

This report describes the acquisition of deep-crustal multichannel seismic-reflection data in the Inner California Borderland aboard the R/V Maurice Ewing, conducted in October 1994 as part of the Los Angeles Regional Seismic Experiment (LARSE). LARSE is a cooperative study of the crustal structure of southern California involving earth scientists from the U.S. Geological Survey, Caltech, the University of Southern California, the University of California Los Angeles, and the Southern California Earthquake Center (SCEC). During LARSE, the R/V Ewing's 20- element air gun array, totaling 137.7 liters (8470 cu. in.), was used as the primary seismic source for wide-angle recording along three main onshore-offshore lines centered on the Los Angeles basin and the epicenters of the 1933 Long Beach and 1994 Northridge earthquakes. The LARSE onshore-offshore lines were each 200-250 km long, with the offshore portions being between 90 and 150 km long. The nearly 24,000 air gun signals generated by the Ewing were recorded by an array of 170 PASSCAL REFTEK recorders deployed at 2 km intervals along all three of the onshore lines and 9 ocean bottom seismometers (OBSs) deployed along two of the lines. Separate passes over the OBS-deployment lines were performed with a long air gun repetition rate (60 and 90 seconds) to minimize acoustic-wave interference from previous shots in the OBS data. The Ewing's 4.2-km, 160-channel, digital streamer was also used to record approximately 1250 km of 40-fold multichannel seismic-reflection data. To enhance the fold of the wide-angle data recorded onshore, mitigating against cultural and wind noise in the Los Angeles basin, the entire ship track was repeated at least once resulting in fewer than about 660 km of unique trackline coverage in the Inner Borderland. Portions of the seismic-reflection lines were repeated up to 6 times. A variety of other geophysical data were also continuously recorded, including 3.5 kHz bathymetry, multi-beam swath Hydrosweep bathymetry, magnetics, and gravity data. In this report, we describe the equipment and procedures used to acquire multichannel seismic-reflection and other geophysical data aboard the Ewing, provide a detailed cruise narrative, discuss the reduction of the data, and present near-trace constant offset seismic sections of the acquired profiles.

An electrocorticographic electrode array for simultaneous recording from medial, lateral, and intrasulcal surface of the cortex in macaque monkeys.

PubMed

Fukushima, Makoto; Saunders, Richard C; Mullarkey, Matthew; Doyle, Alexandra M; Mishkin, Mortimer; Fujii, Naotaka

2014-08-15

Electrocorticography (ECoG) permits recording electrical field potentials with high spatiotemporal resolution over a large part of the cerebral cortex. Application of chronically implanted ECoG arrays in animal models provides an opportunity to investigate global spatiotemporal neural patterns and functional connectivity systematically under various experimental conditions. Although ECoG is conventionally used to cover the gyral cortical surface, recent studies have shown the feasibility of intrasulcal ECoG recordings in macaque monkeys. Here we developed a new ECoG array to record neural activity simultaneously from much of the medial and lateral cortical surface of a single hemisphere, together with the supratemporal plane (STP) of the lateral sulcus in macaque monkeys. The ECoG array consisted of 256 electrodes for bipolar recording at 128 sites. We successfully implanted the ECoG array in the left hemisphere of three rhesus monkeys. The electrodes in the auditory and visual cortex detected robust event related potentials to auditory and visual stimuli, respectively. Bipolar recording from adjacent electrode pairs effectively eliminated chewing artifacts evident in monopolar recording, demonstrating the advantage of using the ECoG array under conditions that generate significant movement artifacts. Compared with bipolar ECoG arrays previously developed for macaque monkeys, this array significantly expands the number of cortical target areas in gyral and intralsulcal cortex. This new ECoG array provides an opportunity to investigate global network interactions among gyral and intrasulcal cortical areas. Published by Elsevier B.V.

New Methods for the Site-Selective Placement of Peptides on a Microelectrode Array: Probing VEGF-v107 Binding as Proof of Concept.

PubMed

Graaf, Matthew D; Marquez, Bernadette V; Yeh, Nai-Hua; Lapi, Suzanne E; Moeller, Kevin D

2016-10-21

Cu(I)-catalyzed "click" reactions cannot be performed on a borate ester derived polymer coating on a microelectrode array because the Cu(II) precursor for the catalyst triggers background reactions between both acetylene and azide groups with the polymer surface. Fortunately, the Cu(II)-background reaction can itself be used to site-selectively add the acetylene and azide nucleophiles to the surface of the array. In this way, molecules previously functionalized for use in "click" reactions can be added directly to the array. In a similar fashion, activated esters can be added site-selectively to a borate ester coated array. The new chemistry can be used to explore new biological interactions on the arrays. Specifically, the binding of a v107 derived peptide with both human and murine VEGF was probed using a functionalized microelectrode array.

An Estimate and Score Algorithm for Simultaneous Parameter Estimation and Reconstruction of Incomplete Data on Social Networks

DTIC Science & Technology

2013-01-12

www.security-informatics.com/content/2/1/1 References 1. SM Radilm, C Flint, GE Tita , Spatializing Social Networks: Using Social Network Analysis to...http://www.tandfonline.com/doi/ abs/10.1080/00045600903550428 2. G Tita , S Radil, Spatializing the social networks of gangs to explore patterns of...violence. Journal of Quantitative Criminology. 27, 1–25 (2011) 3. G Tita , JK Riley, G Ridgeway, AF Abrahamse, P Greenwood, Reducing Gun Violence

Double electrochemical covalent coupling method based on click chemistry and diazonium chemistry for the fabrication of sensitive amperometric immunosensor.

PubMed

Qi, Honglan; Li, Min; Zhang, Rui; Dong, Manman; Ling, Chen

2013-08-20

A double electrochemical covalent coupling method based on click chemistry and diazonium chemistry for the fabrication of sensitive amperometric immunosensor was developed. As a proof-of-concept, a designed alkyne functionalized human IgG was used as a capture antibody and a HRP-labeled rabbit anti-goat IgG was used as signal antibody for the determination of the anti-human IgG using the sandwich model. The immunosensor was fabricated by electrochemically grafting a phenylazide on the surface of a glassy carbon electrode, and then, by coupling the alkyne functionalized human IgG with the phenylazide group through an electro-click chemistry in the presence of Cu(II). The amperometric measurement for the determination of the anti-human IgG was performed after the fabricated immunosensor was incubated with the target anti-human IgG and then with the HRP-labeled anti-goat IgG at -0.25V in 0.10M PBS (pH 7.0) containing 0.1mM hydroquinone and 2.0mM H2O2. The results showed that the increased current was linear with the logarithm of the concentration of the anti-human IgG in the range from 1.0×10(-10)g mL(-1) to 1.0×10(-8)g mL(-1) with a detection limit of 3×10(-11)g mL(-1). Furthermore, the feasibility of the double electrochemical covalent coupling method proposed in this work for fabricating the amperometric immunosensor array was explored. This work demonstrates that the double electrochemical covalent coupling method is a promising approach for the fabrication of the immunosensor and immunosensor array. Copyright © 2013 Elsevier B.V. All rights reserved.

Gun carrying by high school students in Boston, MA: does overestimation of peer gun carrying matter?

PubMed

Hemenway, David; Vriniotis, Mary; Johnson, Renee M; Miller, Matthew; Azrael, Deborah

2011-10-01

This paper investigates: (1) whether high school students overestimate gun carrying by their peers, and (2) whether those students who overestimate peer gun carrying are more likely to carry firearms. Data come from a randomly sampled survey conducted in 2008 of over 1,700 high school students in Boston, MA. Over 5% of students reported carrying a gun, 9% of boys and 2% of girls. Students substantially overestimated the percentage of their peers who carried guns; the likelihood that a respondent carried a gun was strongly associated with their perception of the level of peer gun carrying. Most respondents believed it was easier for other youth to obtain guns than it was for them. Social marketing campaigns designed to lower young people's perceptions about the prevalence of peer gun carrying may be a promising strategy for reducing actual gun carrying among youth. Copyright © 2010 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Threat perception after the Boston Marathon bombings: The effects of personal relevance and conceptual framing.

PubMed

Wormwood, Jolie Baumann; Lynn, Spencer K; Feldman Barrett, Lisa; Quigley, Karen S

2016-01-01

We examined how the Boston Marathon bombings affected threat perception in the Boston community. In a threat perception task, participants attempted to "shoot" armed targets and avoid shooting unarmed targets. Participants viewing images of the bombings accompanied by affectively negative music and text (e.g., "Terror Strikes Boston") made more false alarms (i.e., more errors "shooting" unarmed targets) compared to participants viewing the same images accompanied by affectively positive music and text (e.g., "Boston Strong") and participants who did not view bombing images. This difference appears to be driven by decreased sensitivity (i.e., decreased ability to distinguish guns from non-guns) as opposed to a more liberal bias (i.e., favouring the "shoot" response). Additionally, the more strongly affected the participant was by the bombings, the more their sensitivity was reduced in the negatively framed condition, suggesting that this framing was particularly detrimental to the most vulnerable individuals in the affected community.

DNA methylation array analysis identifies breast cancer associated RPTOR, MGRN1 and RAPSN hypomethylation in peripheral blood DNA.

PubMed

Tang, Qiuqiong; Holland-Letz, Tim; Slynko, Alla; Cuk, Katarina; Marme, Frederik; Schott, Sarah; Heil, Jörg; Qu, Bin; Golatta, Michael; Bewerunge-Hudler, Melanie; Sutter, Christian; Surowy, Harald; Wappenschmidt, Barbara; Schmutzler, Rita; Hoth, Markus; Bugert, Peter; Bartram, Claus R; Sohn, Christof; Schneeweiss, Andreas; Yang, Rongxi; Burwinkel, Barbara

2016-09-27

DNA methylation changes in peripheral blood DNA have been shown to be associated with solid tumors. We sought to identify methylation alterations in whole blood DNA that are associated with breast cancer (BC). Epigenome-wide DNA methylation profiling on blood DNA from BC cases and healthy controls was performed by applying Infinium HumanMethylation450K BeadChips. Promising CpG sites were selected and validated in three independent larger sample cohorts via MassARRAY EpiTyper assays. CpG sites located in three genes (cg06418238 in RPTOR, cg00736299 in MGRN1 and cg27466532 in RAPSN), which showed significant hypomethylation in BC patients compared to healthy controls in the discovery cohort (p < 1.00 x 10-6) were selected and successfully validated in three independent cohorts (validation I, n =211; validation II, n=378; validation III, n=520). The observed methylation differences are likely not cell-type specific, as the differences were only seen in whole blood, but not in specific sub cell-types of leucocytes. Moreover, we observed in quartile analysis that women in the lower methylation quartiles of these three loci had higher ORs than women in the higher quartiles. The combined AUC of three loci was 0.79 (95%CI 0.73-0.85) in validation cohort I, and was 0.60 (95%CI 0.54-0.66) and 0.62 (95%CI 0.57-0.67) in validation cohort II and III, respectively. Our study suggests that hypomethylation of CpG sites in RPTOR, MGRN1 and RAPSN in blood is associated with BC and might serve as blood-based marker supplements for BC if these could be verified in prospective studies.

CT-guided transthoracic needle biopsy: a comparison between automated biopsy gun and fine needle aspiration.

PubMed

Arakawa, H; Nakajima, Y; Kurihara, Y; Niimi, H; Ishikawa, T

1996-07-01

We retrospectively investigated the diagnostic accuracy and complication rate of transthoracic core biopsy using an automated biopsy gun and compared the findings with those of aspiration needle biopsy. Seventy-three patients underwent 74 core biopsy procedures and 50 patients underwent 52 aspiration biopsy procedures. Of these, a final diagnosis was obtained in 107 lesions with surgery or clinical course. Fifteen patients in which a final diagnosis was not obtained were excluded from the study on diagnostic accuracy. Thus, in the study of diagnostic accuracy, 63 core biopsy procedures for 62 lesions are included. Core biopsy was performed with an 18 G cutting needle using an automated biopsy gun. Aspiration biopsy was performed with a 20 G aspiration needle. Core biopsy yielded sufficient material in 57/63 procedures (90.5%). A correct diagnosis was obtained in 36 procedures (85.7%) for malignant leisons and a specific benign diagnosis was obtained in 11 procedures (52.4%). Aspiration biopsy yielded a correct diagnosis in 26 procedures (81.3%) for malignant leisons and in seven (46.7%) for benign lesions. The overall correct diagnosis were 75.8% and 71.7% with core biopsy and aspiration biopsy, respectively. Core biopsy gave a higher predictive rate than that of aspiration biopsy for both benign and malignant lessons (P < 0.02). Pneumothorax occurred in 18/74 (24.3%) patients with core biopsy and in 18/45 (40.0%) patients with aspiration biopsy. Of these, three with core biopsy and two with aspiration biopsy needed tube drainage. The other complication was haemoptysis, which occurred in six patients following core biopsy and in three after aspiration biopsy. All nine cases subsided spontaneously. There were no fatal complications. Core biopsy with a biopsy gun increase the diagnostic accuracy with a higher histologic predictive rate and no obvious additional risk of complications.

Not an 'iron pipeline', but many capillaries: regulating passive transactions in Los Angeles' secondary, illegal gun market.

PubMed

Chesnut, Kelsie Y; Barragan, Melissa; Gravel, Jason; Pifer, Natalie A; Reiter, Keramet; Sherman, Nicole; Tita, George E

2017-08-01

California has strict firearm-related laws and is exceptional in its regulation of firearms retailers. Though evidence suggests that these laws can reduce illegal access to guns, high levels of gun violence persist in Los Angeles (LA), California. This research seeks to describe the sources of guns accessed by active offenders in LA, California and reports offenders' motivations for obtaining guns. Los Angeles County Jail (LACJ) system (four facilities). Random sampling from a screened pool of eligible participants was used to conduct qualitative semistructured interviews with 140 incarcerated gun offenders in one of four (LACJ) facilities. Researchers collected data on firearm acquisition, experiences related to gun violence, and other topics, using a validated survey instrument. Grounded theory guided the collection and analysis of data. Respondents reported possession of 77 specific guns (79.2% handguns) collectively. Social networks facilitate access to illegal guns; the majority of interviewees acquired their illegal guns through a social connection (85.7%) versus an outside broker/unregulated retailer (8.5%). Most guns were obtained through illegal purchase (n=51) or gift (n=15). A quarter of gun purchasers report engaging in a passive transaction, or one initiated by another party. Passive gun buyers were motivated by concerns for personal safety and/or economic opportunity. In LA's illegal gun market, where existing social relationships facilitate access to guns across a diffuse network, individuals, influenced by both fear and economic opportunity, have frequent opportunities to illegally possess firearms through passive transactions. Gun policies should better target and minimise these transactions. 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/.

Gun shows across a multistate American gun market: observational evidence of the effects of regulatory policies

PubMed Central

Wintemute, Garen J

2007-01-01

Objective To describe gun shows and assess the impact of increased regulation on characteristics linked to their importance as sources of guns used in crime. Design Cross‐sectional, observational. Subjects Data were collected at a structured sample of 28 gun shows in California, which regulates these events and prohibits undocumented private party gun sales; and in Arizona, Nevada, Texas and Florida—all leading sources of California's crime guns—where these restrictions do not exist. Main outcome measures Size of shows, measured by numbers of gun vendors and people in attendance; number and nature of guns for sale by gun vendors; measures of private party gun sales and illegal surrogate (“straw”) gun purchases. Results Shows in comparison states were larger, but the number of attendees per gun vendor was higher in California. None of these differences was statistically significant. Armed attendees were more common in other states (median 5.7%, interquartile range (IQR) 3.9–10.0%) than in California (median 1.1%, IQR 0.5–2.2%), p = 0.0007. Thirty percent of gun vendors both in California and elsewhere were identifiable as licensed firearm retailers. There were few differences in the types or numbers of guns offered for sale; vendors elsewhere were more likely to sell assault weapons (34.9% and 13.3%, respectively; p = 0.001). Straw purchases were more common in the comparison states (rate ratio 6.6 (95% CI 0.9 to 49.1), p = 0.06). Conclusions California's regulatory policies were associated with a decreased incidence of anonymous, undocumented gun sales and illegal straw purchases at gun shows. No significant adverse effects of these policies were observed. PMID:17567968

The case for moderate gun control.

PubMed

DeGrazia, David

2014-03-01

In addressing the shape of appropriate gun policy, this essay assumes for the sake of discussion that there is a legal and moral right to private gun ownership. My thesis is that, against the background of this right, the most defensible policy approach in the United States would feature moderate gun control. The first section summarizes the American gun control status quo and characterizes what I call "moderate gun control." The next section states and rebuts six leading arguments against this general approach to gun policy. The section that follows presents a positive case for moderate gun control that emphasizes safety in the home and society as well as rights whose enforcement entails some limits or qualifications on the right to bear arms. A final section shows how the recommended gun regulations address legitimate purposes, rather than imposing arbitrary restrictions on gun rights, and offers concluding reflections.

Very Large Array H I Zeeman Observations of the Cygnus X Region: DR 22 and ON 2

NASA Astrophysics Data System (ADS)

Mayo, E. A.; Troland, T. H.

2012-02-01

We have used the Very Large Array to study the Zeeman effect in 21 cm H I absorption lines from two star-forming regions in the Cygnus X complex, DR 22 and ON 2. We measure the line-of-sight magnetic field toward these regions, finding B los = -84 ± 11 μG toward the DR 22 H II region and B los < 50 μG toward each of the two H II regions in ON 2. We interpret these results in terms of two different models. In one model, we assume that the H I Zeeman effect is a measure of magnetic fields in the associated molecular clouds. If so, then the DR 22 molecular cloud is magnetically subcritical, that is, magnetically dominated. The ON 2 molecular clouds are magnetically supercritical. In a second model, we assume that the H I Zeeman effect is a measure of magnetic fields in photon-dominated regions where the gas has been compressed (and the field amplified) by absorption of stellar radiation. We find that this second model, where the measured field strength has been affected by star formation, accounts well for the DR 22 H I Zeeman effect. This same model, however, overpredicts the magnetic field in ON 2. ON 2 may be a region where the magnetic field is energetically insignificant or where the field happens to lie nearly in the plane of the sky.

Non-Uniform Cathode Emission Studies of a MIG Gun

NASA Astrophysics Data System (ADS)

Marchewka, C. D.; Shapiro, M. A.; Sirigiri, J. R.; Temkin, R. J.

2004-11-01

We present the initial results of the modeling of the effect of emission non-uniformity in 96 kV, 40 A Magnetron Injection Gun (MIG) of a 1.5 MW 110 GHz gyrotron using a 3D gun simulation code. The azimuthal emission nonuniformity can lead to increased mode competition and an overall decreased efficiency of the device [1]. The electron beam is modeled from the cathode to a downstream position where the velocity spread saturates using the AMAZE 3D suite of codes. After bench marking the results of the 3D code with 2D codes such as TRAK2D and EGUN, the emitter was modified to simulate asymmetric emission from the cathode to gain an understanding into the effects of inhomogeneous beam current density on the velocity spread and pitch factor of the electron beam. [1] G. S. Nusinovich, A.N. Vlasov, M. Botton, T. M. Antonsen, Jr., S. Cauffman, K. Felch, ``Effect of the azimuthal inhomogeneity of electron emission on gyrotron operation,'' Phys. Plasmas, vol. 8, no. 7, pp. 3473-3479, 2001

Design simulations for a small emittance 2.7-cell photo-cathode rf-gun in jector

NASA Astrophysics Data System (ADS)

Yongzhang, Huang

1997-05-01

In order to produce the electron bunch with small emittance which is the key issue in the so-called SASE studies, the design studies on a two-and-half cell photocathode rf-gun has been conducted. The rf gun injector is optimized by using the code of Par mela. As a main result, the optimum is found to be a 2.7-cell cavity. The geometry and the coupling scheme of the requested cavity is studied in more detail with the codes of Mafia and Superfish. The beam iris of each cells is enlarged in order to wide n the mode separations. For the purpose of cancelling the influence of the coupling iris upon the field symmetry, the so-called symmetrical double-side input coupler is studied. The coupler will be assembled to the second cell and the critical matchin g has been achieved in the Mafia-T3 simulation. With this cavity, the final normalized rms emittance reaches the value of 0.81πmm-mrad at a charge of 1nC in the Parmela simulation.

Shock Initiation Behavior of PBXN-9 Determined by Gas Gun Experiments

NASA Astrophysics Data System (ADS)

Sanchez, N. J.; Gustavsen, R. L.; Hooks, D. E.

2009-12-01

The shock to detonation transition was evaluated in the HMX based explosive PBXN-9 by a series of light-gas gun experiments. PBXN-9 consists of 92 wt% HMX, 2wt% Hycar 4054 & 6 wt&percent; dioctyl adipate with a density of 1.75 g/cm3 and 0.8&% voids. The experiments were designed to understand the specifics of wave evolution and the run distance to detonation as a function of input shock pressure. These experiments were conducted on gas guns in order to vary the input shock pressure accurately. The primary diagnostics were embedded magnetic gauges, which are based on Faraday's law of induction, and Photon Doppler Velocimetry (PDV). The run distance to detonation vs. shock pressure, or "Pop plot," was redefined as log(X) = 2.14-1.82 log (P), which is substantially different than previous data. The Hugoniot was refined as Us = 2.32+2.211 Up. This data will be useful for the development of predictive models for the safety and performance of PBXN-9 along with providing increased understanding of HMX based explosives in varying formulations.

Shock initiation behavior of PBXN-9 determined by gas gun experiments

NASA Astrophysics Data System (ADS)

Sanchez, Nathaniel; Gustavsen, Richard; Hooks, Daniel

2009-06-01

The shock to detonation transition was evaluated in the HMX based explosive PBXN-9 by a series of light-gas gun experiments. PBXN-9 consists of 92 wt% HMX, 2wt% Hycar 4054 & 6 wt% dioctyl adipate with a density of 1.75 g/cm^3 and 0.8% voids. The experiments were designed to understand the specifics of wave evolution and the run distance to detonation as a function of input shock pressure. These experiments were conducted on gas guns in order to vary the input shock pressure accurately. The primary diagnostics are embedded magnetic gauges which are based on Faraday's law of induction along with photon Doppler velocimetry (PDV). The run distance to detonation vs. shock pressure, or ``Pop plot,'' was redefined as log (X*) = 2.14 -- 1.82 log (P), which is substantially different than previous data. The Hugoniot was refined as Us = 2.32 + 2.21 Up. This data will be useful for the development of predictive models for the safety and performance of PBXN-9 in addition to providing an increased understanding of HMX based explosives in varying formulations.

Investigation of internal magnetic structures and comparison with two-fluid equilibrium configurations in the multi-pulsing CHI on HIST

NASA Astrophysics Data System (ADS)

Nakayama, T.; Hanao, T.; Hirono, H.; Hyobu, T.; Ito, K.; Matsumoto, K.; Kikuchi, Y.; Fukumoto, N.; Nagata, M.; Kanki, T.

2012-10-01

Spherical torus (ST) plasmas have been successfully maintained by Muti-pulsing Coaxial Helicity Injection (M-CHI) on HIST. This research object is to clarify relations between plasma characteristics and magnetic flux amplifications, and to compare magnetic field structures measured in the plasma interior to a flowing equilibrium calculation. Two-dimensional magnetic probe array has been newly introduced nearby the gun muzzle. The initial result shows that the diverter configuration with a single X-point can be formed after a bubble burst process of the plasma. The closed magnetic flux is surrounded by the open magnetic field lines intersecting with the gun electrodes. To evaluate the sustained configurations, we use the two-fluid equilibrium code containing generalized Bernoulli and Grad-Shafranov equations which was developed by L.C. Steinhauer. The radial profiles of plasma flow, density and magnetic fields measured on the midplane of the FC are consistent to the calculation. We also found that the poloidal shear flow generation is attributed to ExB drift and ion diamagnetic drift. In addition, we will study temporal behaviors of impurity lines such as OV and OVI during the flux amplification by VUV spectroscopic measurements.

Capabilities of NASA/Marshall Space Flight Center's Impact Testing Facility

NASA Technical Reports Server (NTRS)

Hovater, Mary; Hubbs, Whitney; Finchum, Andy; Evans, Steve; Nehls, Mary

2006-01-01

The Impact Testing Facility (ITF) serves as an important installation for materials science at Marshall Space Flight Center (MSFC). With an array of air, powder, and two-stage light gas guns, a variety of projectile and target types and sizes can be accommodated. The ITF allows for simulation of impactors from rain to micrometeoroids and orbital debris on materials being investigated for space, atmospheric, and ground use. Expendable, relatively simple launch assemblies are used to obtain well-documented results for impact conditions comparable to those from ballistic and rocket sled ranges at considerably lower cost. In addition, for applications requiring study of impacts at speeds in excess of those attainable by gun launches, hydrocode simulations, validated by test data, can be used to extend the velocity range. In addition to serving various NASA directorates, the ITF has performed testing on behalf of the European and Russian space agencies, as well as the Department of Defense, and academic institutions. The m s contributions not only enable safer space flight for NASA s astronauts, but can help design materials and structures to protect soldiers and civilians on Earth, through advances in body armor, aircraft survivability, and a variety of other applications.

A Ka-Band (26 GHz) Circularly Polarized 2x2 Microstrip Patch Sub-Array with Compact Feed

NASA Technical Reports Server (NTRS)

Chrysler, Andrew; Furse, Cynthia; Simons, Rainee N.; Miranda, Felix A.

2017-01-01

A Ka-Band (26 gigahertz) 2 by 2 sub-array with square-shaped microstrip patch antenna elements having two truncated corners for circular polarization (CP) is presented. In addition, the layout for a new compact microstrip feed network for the sub-array is also presented. The compact feed network offers a footprint size reduction of near 60 percent over traditional sub-array at 26 gigahertz. Experimental data indicates that a truncation amount a equals 0.741 millimeters for an isolated patch element results in a return loss (S (sub II)) of minus 35 decibels at 26.3 gigahertz. Furthermore, the measured S (sub II) for the proof-of-concept sub-array with the above elements is better than minus 10.0 decibels at 27.7 gigahertz. However, the impedance match and the operating frequency can be fine-tuned to 26 gigahertz by adjusting the feed network dimensions. Lastly, good agreement is observed between the measured and simulated S (sub II) for the subarray for both right hand and left hand CP. The goal of this effort is utilize the above sub-array as a building block for a larger N by N element array, which would serve as a feed for a reflector antenna for satellite communications.

Goods for Guns--the use of a gun buyback as an injury prevention/community education tool.

PubMed

McGuire, Margaret; Manno, Mariann; Rook, Allison; Maranda, Louise; Renaud, Elizabeth; DeRoss, Anthony; Hirsh, Michael

2011-11-01

US children aged between 5 years and 14 years have a rate of gun-related homicide 17 times higher and a rate of gun-related suicide and unintentional firearm injury 10 times higher than other developed countries. Gun buyback programs have been criticized as ineffective interventions in decreasing violence. The Injury Free Coalition for Kids-Worcester (IFCK-W) Goods for Guns buyback is a multipronged approach to address these concerns and to reduce the number of firearms in the community. The IFCK-W buyback program is funded by corporate sponsors, grants, and individual donations. Citizens are instructed to transport guns, ammunition, and weapons safely to police headquarters on two Saturdays in December. Participants are guaranteed anonymity by the District Attorney's office and receive gift certificates for operable guns. Trained volunteers administer an anonymous survey to willing participants. Individuals who disclose having unsafely stored guns remaining at home receive educational counseling and trigger locks. Guns and ammunition are destroyed at a later time in a gun crushing ceremony. Since 2002, 1,861 guns (444 rifle/shotgun, 738 pistol/revolver, and 679 automatic/semiautomatic) have been collected at a cost of $99,250 (average, $53/gun). Seven hundred ten people have surrendered firearms, 534 surveys have been administered, and ≈ 75 trigger locks have been distributed per year. IFCK-W Goods for Guns is a relatively inexpensive injury prevention model program that removes unwanted firearms from homes, raises community awareness about gun safety, and provides high-risk individuals with trigger locks and educational counseling.

Interior of southeast gun chamber (labeled "Gun Turret No. Two), ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Interior of southeast gun chamber (labeled "Gun Turret No. Two), showing gun mounting pad, wall rings, small niche, and opening to outside - U.S. Naval Base, Pearl Harbor, Battery Adair, Princeton Place, Pearl City, Honolulu County, HI

46 CFR 160.031-4 - Equipment for shoulder gun type line-throwing appliance.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 6 2014-10-01 2014-10-01 false Equipment for shoulder gun type line-throwing appliance... Appliance, Shoulder Gun Type (and Equipment) § 160.031-4 Equipment for shoulder gun type line-throwing... the gun. The line canister shall be secured by clamps or brackets below the barrel of the gun. (c) One...

46 CFR 160.031-4 - Equipment for shoulder gun type line-throwing appliance.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 6 2010-10-01 2010-10-01 false Equipment for shoulder gun type line-throwing appliance... Appliance, Shoulder Gun Type (and Equipment) § 160.031-4 Equipment for shoulder gun type line-throwing... the gun. The line canister shall be secured by clamps or brackets below the barrel of the gun. (c) One...

46 CFR 160.031-4 - Equipment for shoulder gun type line-throwing appliance.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 6 2013-10-01 2013-10-01 false Equipment for shoulder gun type line-throwing appliance... Appliance, Shoulder Gun Type (and Equipment) § 160.031-4 Equipment for shoulder gun type line-throwing... the gun. The line canister shall be secured by clamps or brackets below the barrel of the gun. (c) One...

46 CFR 160.031-4 - Equipment for shoulder gun type line-throwing appliance.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 6 2012-10-01 2012-10-01 false Equipment for shoulder gun type line-throwing appliance... Appliance, Shoulder Gun Type (and Equipment) § 160.031-4 Equipment for shoulder gun type line-throwing... the gun. The line canister shall be secured by clamps or brackets below the barrel of the gun. (c) One...

46 CFR 160.031-4 - Equipment for shoulder gun type line-throwing appliance.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 6 2011-10-01 2011-10-01 false Equipment for shoulder gun type line-throwing appliance... Appliance, Shoulder Gun Type (and Equipment) § 160.031-4 Equipment for shoulder gun type line-throwing... the gun. The line canister shall be secured by clamps or brackets below the barrel of the gun. (c) One...

An Exploratory Investigation of the Influence of Igniter Chemistry on Ignition in Porous Bed Gun Propellants

DTIC Science & Technology

1981-09-01

nitrocellulose igniter materials using the Ignition Energetics Characterization Device (IECD). The results presented herein represent Phase II eperimental ...auxiliary test cham- bcz is a combustion gas diagnostic section designed to permit determination of the composition and enthalpy level of the gases...removal/assembly and propellant loading. 2.2 Igniter Characteristics 2.2.1 Baseline Igniter The igniter system, Figure 2.3, is designed to provide overall

MEMS Gate Structures for Electric Propulsion Applications

DTIC Science & Technology

2006-07-12

distance between gates of dual gate system V = grid voltage Dsheath = sheath thickness Va = anode voltage E = electric field Vemitter = emitter voltage Es...minutes. A hot pressed boron nitride target (4N) in the hexagonal phase (h- BN) was sputtered in a RF magnetron sputtering gun. To promote the nucleation...and nanoFETs. This paper concludes with a discussion on using MEMS gates for dual -grid electron field emission applications. II. Gate Design I I

Effects on Training of Experimental Film Variables Study II. Verbalization, "How-It-Works," Nomenclature, Audience Participation, and Succinct Treatment. Rapid Mass Learning. Technical Report.

ERIC Educational Resources Information Center

Jaspen, N.

A study was conducted to ascertain which characteristics of instructional films affect learning. Fourteen versions of a film designed to teach the assembly of part of an anti-aircraft gun were prepared and shown to different groups of trainees. The study examined the following factors: 1) number of words of narration used to describe the action,…

Gun Violence, Mental Illness, And Laws That Prohibit Gun Possession: Evidence From Two Florida Counties

PubMed Central

Swanson, Jeffrey W.; Easter, Michele M.; Robertson, Allison G.; Swartz, Marvin S.; Alanis-Hirsch, Kelly; Moseley, Daniel; Dion, Charles; Petrila, John

2016-01-01

Gun violence kills about ninety people every day in the United States, a toll measured in wasted and ruined lives and with an annual economic price tag exceeding $200 billion. Some policy makers suggest that reforming mental health care systems and improving point-of-purchase background checks to keep guns from mentally disturbed people will address the problem. Epidemiological research shows that serious mental illness contributes little to the risk of interpersonal violence but is a strong factor in suicide, which accounts for most firearm fatalities. Meanwhile, the effectiveness of gun restrictions focused on mental illness remains poorly understood. This article examines gun-related suicide and violent crime in people with serious mental illnesses, and whether legal restrictions on firearm sales to people with a history of mental health adjudication are effective in preventing gun violence. Among the study population in two large Florida counties, we found that 62 percent of violent gun crime arrests and 28 percent of gun suicides involved individuals not legally permitted to have a gun at the time. Suggested policy reforms include enacting risk-based gun removal laws and prohibiting guns from people involuntarily detained in short-term psychiatric hospitalizations. PMID:27269024

The life cycle of crime guns: a description based on guns recovered from young people in California.

PubMed

Wintemute, Garen J; Romero, Michael P; Wright, Mona A; Grassel, Kevin M

2004-06-01

We describe the life cycle of crime guns recovered from young people-the movement of those guns from manufacture to criminal use-and identify associations between the characteristics of those guns and their possessors, purchasers, sellers, and places of origin. This is a cross-sectional study of data from gun ownership tracing records compiled by the Bureau of Alcohol, Tobacco, Firearms and Explosives for 2,121 crime guns recovered in California from persons younger than 25 years and traced in 1999. Purchaser and seller data for handguns were updated when possible by linking to California handgun sales records. The 2,121 traced guns were recovered from 1,717 young people. Guns recovered from persons aged 21 to 24 years were most frequently also purchased by persons aged 21 to 24 years; those recovered from persons younger than 18 years were most often purchased by persons aged 45 years or older. Small-caliber handguns made up 41.0% of handguns recovered from persons younger than 18 years but 25.2% of handguns recovered from persons aged 21 to 24 years. The median time from sale to recovery (commonly called time to crime) for all guns was 6.4 years (interquartile range 2.7 to 12.4 years). A time to crime of less than 3 years, suggesting deliberate gun trafficking, was observed for 17.3% of guns recovered from persons younger than 18 years but 34.6% of guns recovered from persons aged 21 to 24 years. Ten retailers who sold 10 or more traced guns accounted for 13.1% of all guns traced to a retailer. Handguns whose purchaser and possessor were the same person were more likely than others to be large-caliber semiautomatic pistols (29.3% and 11.7%, respectively); their median time to crime was 0.2 years (69 days). Analysis of crime-gun ownership traces reveals patterns that may help refine gun violence prevention efforts and render them more effective.

Enhanced photoemission from glancing angle deposited SiOx-TiO2 axial heterostructure nanowire arrays

NASA Astrophysics Data System (ADS)

Dhar, J. C.; Mondal, A.; Singh, N. K.; Chattopadhyay, K. K.

2013-05-01

The glancing angle deposition technique has been employed to synthesize SiOx-TiO2 heterostructure nanowire (NW) arrays on indium tin oxide (ITO) coated glass substrate. A field emission gun scanning electron microscopic image shows that the average diameter of the NWs is ˜50 nm. Transmission electron microscopy images show the formation of heterostructure NWs, which consist of ˜180 nm SiOx and ˜210 nm long TiO2. The selected-area electron diffraction shows the amorphous nature of the synthesized NWs, which was also confirmed by X-ray diffraction method. The main band absorption edges at 3.5 eV were found for both the SiOx-TiO2 and TiO2 NW arrays on ITO coated glass plate from optical absorption measurement. Ti3+ defect related sub-band gap transition at 2.5 eV was observed for TiO2 NWs, whereas heterostructure NWs revealed the SiOx optical band gap related transition at ˜2.2 eV. Two fold improved photon absorption as well as five times photoluminescence emission enhancement were observed for the SiOx-TiO2 multilayer NWs compared to TiO2 NWs.

Phosphorylation of GENOMES UNCOUPLED 4 Alters Stimulation of Mg Chelatase Activity in Angiosperms1[OPEN

PubMed Central

Hochheuser, Caroline; Fufezan, Christian; Heinze, Laura

2016-01-01

GENOMES UNCOUPLED 4 (GUN4) is a positive regulator of light-dependent chlorophyll biosynthesis. GUN4 activates Mg chelatase (MgCh) that catalyzes the insertion of an Mg2+ ion into protoporphyrin IX. We show that Arabidopsis (Arabidopsis thaliana) GUN4 is phosphorylated at Ser 264 (S264), the penultimate amino acid residue at the C terminus. While GUN4 is preferentially phosphorylated in darkness, phosphorylation is reduced upon accumulation of Mg porphyrins. Expression of a phosphomimicking GUN4(S264D) results in an incomplete complementation of the white gun4-2 null mutant and a chlorotic phenotype comparable to gun4 knockdown mutants. Phosphorylated GUN4 has a reduced stimulatory effect on MgCh in vitro and in vivo but retains its protein stability and tetrapyrrole binding capacity. Analysis of GUN4 found in oxygenic photosynthetic organisms reveals the evolution of a C-terminal extension, which harbors the phosphorylation site of GUN4 expressed in angiosperms. Homologs of GUN4 from Synechocystis and Chlamydomonas lack the conserved phosphorylation site found in a C-terminal extension of angiosperm GUN4. Biochemical studies proved the importance of the C-terminal extension for MgCh stimulation and inactivation of GUN4 by phosphorylation in angiosperms. An additional mechanism regulating MgCh activity is proposed. In conjunction with the dark repression of 5-aminolevulinic acid synthesis, GUN4 phosphorylation minimizes the flow of intermediates into the Mg branch of the tetrapyrrole metabolic pathway for chlorophyll biosynthesis. PMID:27688621

An electrocorticographic electrode array for simultaneous recording from medial, lateral, and intrasulcal surface of the cortex in macaque monkeys

PubMed Central

Fukushima, Makoto; Saunders, Richard C.; Mullarkey, Matthew; Doyle, Alexandra M.; Mishkin, Mortimer; Fujii, Naotaka

2014-01-01

Background Electrocorticography (ECoG) permits recording electrical field potentials with high spatiotemporal resolution over a large part of the cerebral cortex. Application of chronically implanted ECoG arrays in animal models provides an opportunity to investigate global spatiotemporal neural patterns and functional connectivity systematically under various experimental conditions. Although ECoG is conventionally used to cover the gyral cortical surface, recent studies have shown the feasibility of intrasulcal ECoG recordings in macaque monkeys. New Method Here we developed a new ECoG array to record neural activity simultaneously from much of the medial and lateral cortical surface of a single hemisphere, together with the supratemporal plane (STP) of the lateral sulcus in macaque monkeys. The ECoG array consisted of 256 electrodes for bipolar recording at 128 sites. Results We successfully implanted the ECoG array in the left hemisphere of three rhesus monkeys. The electrodes in the auditory and visual cortex detected robust event related potentials to auditory and visual stimuli, respectively. Bipolar recording from adjacent electrode pairs effectively eliminated chewing artifacts evident in monopolar recording, demonstrating the advantage of using the ECoG array under conditions that generate significant movement artifacts. Comparison with Existing Methods Compared with bipolar ECoG arrays previously developed for macaque monkeys, this array significantly expands the number of cortical target areas in gyral and intralsulcal cortex. Conclusions This new ECoG array provides an opportunity to investigate global network interactions among gyral and intrasulcal cortical areas. PMID:24972186

The MicroArray Quality Control (MAQC)-II study of common practices for the development and validation of microarray-based predictive models

EPA Science Inventory

The second phase of the MicroArray Quality Control (MAQC-II) project evaluated common practices for developing and validating microarray-based models aimed at predicting toxicological and clinical endpoints. Thirty-six teams developed classifiers for 13 endpoints - some easy, som...

Impurities, temperature, and density in a miniature electrostatic plasma and current source

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

Den Hartog, D.J.; Craig, D.J.; Fiksel, G.

1996-10-01

We have spectroscopically investigated the Sterling Scientific miniature electrostatic plasma source-a plasma gun. This gun is a clean source of high density (10{sup 19} - 10{sup 20} m{sup -3}), low temperature (5 - 15 eV) plasma. A key result of our investigation is that molybdenum from the gun electrodes is largely trapped in the internal gun discharge; only a small amount escapes in the plasma flowing out of the gun. In addition, the gun plasma parameters actually improve (even lower impurity contamination and higher ion temperature) when up to 1 kA of electron current is extracted from the gun viamore » the application of an external bias. This improvement occurs because the internal gun anode no longer acts as the current return for the internal gun discharge. The gun plasma is a virtual plasma electrode capable of sourcing an electron emission current density of 1 kA/cm{sup 2}. The high emission current, small size (3 - 4 cm diameter), and low impurity generation make this gun attractive for a variety of fusion and plasma technology applications.« less

Research on vibration characteristics of gun barrel based on contact model

NASA Astrophysics Data System (ADS)

Zhao, Yang; Zhou, Qizheng; Yue, Pengfei

2017-04-01

In order to study vibration characteristics of the gun barrel under the action of moving projectile, the gun barrel is simplified to cross sectional cantilever beam such as Euler. Considering contact conditions of inertia effect and projectile with the gun barrel, the equation of lateral vibration of the gun barrel is established under the projectile-gun coupling effect; the modal analysis method is used to give the analytic solutions of equation series. The effect of the motion parameters the projectile on the vibration of gun barrel is discussed, and characteristics of vibration of gun barrel are further studied under two conditions of repeating and projectile with mass eccentricity. The research results show that reasonable control of the acceleration of the projectile in the gun bore, and reduction of projectile mass eccentricity can help reduce the muzzle vibration at the gun firing. The research results can provide reference for overall design of the gun, and the modeling and analysis method used in the paper can be promoted for the solution of vibration of other related projects under the moving excitation.

A gasdynamic gun driven by gaseous detonation

NASA Astrophysics Data System (ADS)

Li, Jinping; Chen, Hong; Zhang, Shizhong; Zhang, Xiaoyuan; Yu, Hongru

2016-01-01

A gasdynamic gun driven by gaseous detonation was developed to address the disadvantages of the insufficient driving capability of high-pressure gas and the constraints of gunpowder. The performance of this gasdynamic gun was investigated through experiments and numerical simulations. Much more powerful launching capability was achieved by this gun relative to a conventional high-pressure gas gun, owing to the use of the chemical energy of the driver gas. To achieve the same launching condition, the initial pressure required for this gun was an order of magnitude lower than that for a gun driven by high-pressure H2. Because of the presence of the detonation, however, a more complex internal ballistic process of this gun was observed. Acceleration of projectiles for this gun was accompanied by a series of impulse loads, in contrast with the smooth acceleration for a conventional one, which indicates that this gun should be used conditionally. The practical feasibility of this gun was verified by experiments. The experiments demonstrated the convenience of taking advantage of the techniques developed for detonation-driven shock tubes and tunnels.

The Gun Dispute.

ERIC Educational Resources Information Center

Spitzer, Robert J.

1999-01-01

Explores the debate over gun ownership and gun control in the United States, focusing on the historic place of guns in U.S. society. The current national mood is more receptive than ever to restricting and regulating adolescent access to guns in light of recent school shootings. (SLD)

Optimization of a two stage light gas gun. M.S. Thesis

NASA Technical Reports Server (NTRS)

Rynearson, R. J.; Rand, J. L.

1972-01-01

Performance characteristics of the Texas A&M University light gas gun are presented along with a review of basic gun theory and popular prediction methods. A computer routine based on the simple isentropic compression method is discussed. Results from over 60 test shots are given which demonstrate an increase in gun muzzle velocity from 9.100 ft/sec. to 19,000 ft/sec. The data gathered indicated the Texas A&M light gas gun more closely resembles an isentropic compression gun rather than a shock compression gun.

Surface-plasmon enhanced photoemission of a silver nano-patterned photocathode

DOE PAGES

Zhang, Z.; Li, R.; To, H.; ...

2016-11-22

Here, nano-patterned photocathodes (NPC) take advantage of plasmonic effects to resonantly increase absorption of light and localize electromagnetic field intensity on metal surfaces leading to surface-plasmon enhanced photoemission. In this paper, we report the status of NPC research at UCLA including in particular the optimization of the dimensions of a nanohole array on a silver wafer to enhance plasmonic response at 800 nm light, the development of a spectrally-resolved reflectivity measurement setup for quick nanopattern validation, and of a novel cathode plug to enable high power tests of NPCs on single crystal substrates in a high gradient radiofrequency gun.

Surface-plasmon enhanced photoemission of a silver nano-patterned photocathode

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

Zhang, Z.; Li, R.; To, H.

Here, nano-patterned photocathodes (NPC) take advantage of plasmonic effects to resonantly increase absorption of light and localize electromagnetic field intensity on metal surfaces leading to surface-plasmon enhanced photoemission. In this paper, we report the status of NPC research at UCLA including in particular the optimization of the dimensions of a nanohole array on a silver wafer to enhance plasmonic response at 800 nm light, the development of a spectrally-resolved reflectivity measurement setup for quick nanopattern validation, and of a novel cathode plug to enable high power tests of NPCs on single crystal substrates in a high gradient radiofrequency gun.

Correlates of Gun Involvement and Aggressiveness among Adolescents.

ERIC Educational Resources Information Center

Ding, Cody S.; Nelsen, Edward A.; Lassonde, Cynthia T.

2002-01-01

Investigated adolescents' aggressiveness in relation to their experiences, beliefs, and attitudes concerning gun use, also noting family composition, relationships with parents, and emotionality as correlates of gun involvement and aggression. Student surveys indicated links between gun ownership and recreational use, beliefs about gun use, and…

High Excitation Rydberg Levels of Fe I from the ATMOS Solar Spectrum at 2.5 and 7 microns

NASA Technical Reports Server (NTRS)

Schoenfeld, W. G.; Chang, E. S.; Geller, M.; Johansson, S.; Nave, G.; Sauval, A. J.; Grevesse, N.

1995-01-01

The quadrupole-polarization theory has been applied to the 3d(sup 6)4S(D-6)4f and 5g subconfigurations of Fe I by a parametric fit, and the fitted parameters are used to predict levels in the 6g and 6h subconfigurations. Using the predicted values, we have computed the 4f-6g and 5g-6h transition arrays and made identifications in the ATMOS infrared solar spectrum. The newly identified 6g and 6h levels, based on ATMOS wavenumbers, are combined with the 5g levels and found to agree with the theoretical values with a root mean-squared-deviation of 0.042/ cm. Our approach yields a polarizability of 28.07 a(sub o, sup 2) and a quadrupole moment of 0.4360 +/- 0.0010 ea(sup 2, sub o) for Fe II, as well as an improved ionization potential of 63737.700 +/- 0.010/ cm for Fe I.

Ship to Shore Connector Amphibious Craft (SSC)

DTIC Science & Technology

2015-12-01

M2 .50 Caliber (12.7mm) Machine Gun ...MK19 40mm Grenade Machine Gun and M60/M240 Series 7.62mm Light Machine Gun . TBD The SSC shall provide protection to the crew and internally... Machine Gun , MK19 40mm Grenade Machine Gun and M60/M240 Series 7.62mm Light Machine Gun . Survivability (Sea-Worthiness) T=O The SSC shall be

And the survey said.... evaluating rationale for participation in gun buybacks as a tool to encourage higher yields.

PubMed

Kasper, Rebecca E; Green, Jonathan; Damle, Rachelle N; Aidlen, Jeremy; Nazarey, Pradeep; Manno, Mariann; Borer, Esther; Hirsh, Michael P

2017-02-01

Gun buyback programs represent one arm of a multipronged approach to raise awareness and education about gun safety. The city of Worcester, MA has conducted an annual gun buyback at the Police Department Headquarters since 2002. We analyzed survey responses from a voluntary, 18-question, face-to-face structured interview from December 2009 to June 2015 using descriptive statistics to determine participant demographics and motivations for participation. A total of 943 guns were collected, and 273 individuals completed surveys. The majority of participants were white males older than 55years (42.4%). Participants represented 61 zip codes across Worcester County, with 68% having prior gun safety training and 61% with weapons remaining in the home (27% of which children could potentially access). The top reasons for turning in guns were "no longer needed" (48%) and "fear of children accessing the gun" (14%). About 1 in 3 respondents knew someone injured/killed by gun violence. Almost all (96%) respondents claimed the program raised community awareness of firearm risk. The Worcester Goods for Guns Buyback has collected more than 900 guns between 2009 and 2015. The buyback removes unwanted guns from homes and raises community awareness about firearm safety. Copyright © 2017 Elsevier Inc. All rights reserved.

RF Design of the LCLS Gun

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

Limborg-Deprey, C

Final dimensions for the LCLS RF gun are described. This gun, referred to as the LCLS gun, is a modified version of the UCLA/BNL/SLAC 1.6 cell S-Band RF gun [1], referred to as the prototype gun. The changes include a larger mode separation (15 MHz for the LCLS gun vs. 3.5 MHz for the prototype gun), a larger radius at the iris between the 2 cells, a reduced surface field on the curvature of the iris between the two cells, Z power coupling, increased cooling channels for operation at 120 Hz, dual rf feed, deformation tuning of the full cell,more » and field probes in both cells. Temporal shaping of the klystron pulse, to reduce the average power dissipated in the gun, has also been adopted. By increasing the mode separation, the amplitude of the 0-mode electric field on the cathode decreases from 10% of the peak on axis field for the prototype gun to less than 3% for the LCLS gun for the steady state fields. Beam performance is improved as shown by the PARMELA simulations. The gun should be designed to accept a future load lock system. Modifications follow the recommendations of our RF review committee [2]. Files and reference documents are compiled in Section IV.« less

Gun Violence, Mental Illness, And Laws That Prohibit Gun Possession: Evidence From Two Florida Counties.

PubMed

Swanson, Jeffrey W; Easter, Michele M; Robertson, Allison G; Swartz, Marvin S; Alanis-Hirsch, Kelly; Moseley, Daniel; Dion, Charles; Petrila, John

2016-06-01

Gun violence kills about ninety people every day in the United States, a toll measured in wasted and ruined lives and with an annual economic price tag exceeding $200 billion. Some policy makers suggest that reforming mental health care systems and improving point-of-purchase background checks to keep guns from mentally disturbed people will address the problem. Epidemiological research shows that serious mental illness contributes little to the risk of interpersonal violence but is a strong factor in suicide, which accounts for most firearm fatalities. Meanwhile, the effectiveness of gun restrictions focused on mental illness remains poorly understood. This article examines gun-related suicide and violent crime in people with serious mental illnesses, and whether legal restrictions on firearm sales to people with a history of mental health adjudication are effective in preventing gun violence. Among the study population in two large Florida counties, we found that 62 percent of violent gun crime arrests and 28 percent of gun suicides involved individuals not legally permitted to have a gun at the time. Suggested policy reforms include enacting risk-based gun removal laws and prohibiting guns from people involuntarily detained in short-term psychiatric hospitalizations. Project HOPE—The People-to-People Health Foundation, Inc.

The prototype cameras for trans-Neptunian automatic occultation survey

NASA Astrophysics Data System (ADS)

Wang, Shiang-Yu; Ling, Hung-Hsu; Hu, Yen-Sang; Geary, John C.; Chang, Yin-Chang; Chen, Hsin-Yo; Amato, Stephen M.; Huang, Pin-Jie; Pratlong, Jerome; Szentgyorgyi, Andrew; Lehner, Matthew; Norton, Timothy; Jorden, Paul

2016-08-01

The Transneptunian Automated Occultation Survey (TAOS II) is a three robotic telescope project to detect the stellar occultation events generated by TransNeptunian Objects (TNOs). TAOS II project aims to monitor about 10000 stars simultaneously at 20Hz to enable statistically significant event rate. The TAOS II camera is designed to cover the 1.7 degrees diameter field of view of the 1.3m telescope with 10 mosaic 4.5k×2k CMOS sensors. The new CMOS sensor (CIS 113) has a back illumination thinned structure and high sensitivity to provide similar performance to that of the back-illumination thinned CCDs. Due to the requirements of high performance and high speed, the development of the new CMOS sensor is still in progress. Before the science arrays are delivered, a prototype camera is developed to help on the commissioning of the robotic telescope system. The prototype camera uses the small format e2v CIS 107 device but with the same dewar and also the similar control electronics as the TAOS II science camera. The sensors, mounted on a single Invar plate, are cooled to the operation temperature of about 200K as the science array by a cryogenic cooler. The Invar plate is connected to the dewar body through a supporting ring with three G10 bipods. The control electronics consists of analog part and a Xilinx FPGA based digital circuit. One FPGA is needed to control and process the signal from a CMOS sensor for 20Hz region of interests (ROI) readout.

Reporter gene expression in dendritic cells after gene gun administration of plasmid DNA.

PubMed

Watkins, Craig; Hopkins, John; Harkiss, Gordon

2005-07-21

Dendritic cells (DC) play an integral role in plasmid DNA vaccination. However, the interaction between plasmid DNA and DC in vivo is incompletely understood. In this report, we utilise the sheep pseudoafferent cannulation model to examine the interaction between plasmid DNA encoding enhanced green fluorescent protein (pEGFP) and afferent lymph DC (ALDC) following gene gun administration. The results show that peaks of fluorescent ALDC tended to appear around days 1-4 and 9-13, then erratically thereafter for up to 2 months. Phenotypic analysis showed that EGFP+ ALDC expressed MHC class II, WC6, CD1b, and SIRPalpha markers. Plasmid, detected by PCR, was found in lymph cells and cell-free plasma on a daily basis, and was present variably for up to 2 months. Plasmid was also detected in purified CD1b+ ALDC, but the presence of plasmid did not correlate with EGFP expression by ALDC. Free EGFP in afferent lymph plasma was detectable by luminometry only after three administrations of the plasmid. The results show that gene gun administered pEGFP persisted for extended periods after a single administration, leeching out of skin on a daily basis. The plasmid was associated with both the cellular and fluid components of afferent lymph. EGFP protein appeared in afferent lymph in a pulsatile manner, but associated only with ALDC.

Encyclopedia of Gun Control and Gun Rights.

ERIC Educational Resources Information Center

Utter, Glenn H.

This reference volume provides information on gun control and gun rights, including resources on the debate surrounding the Second Amendment and individuals and organizations focused on gun issues, along with statutes, court cases, events, and publications surrounding this current topic. Highlighted are the important organizations and their…

Psychology Needs Realism, Not Instrumentalism

ERIC Educational Resources Information Center

Haig, Brian D.

2005-01-01

In this article, the author presents his comments on "Realism, Instrumentalism, and Scientific Symbiosis: Psychological Theory as a Search for Truth and the Discovery of Solutions" by John T. Cacioppo, Gun R. Semin and Gary G. Berntson. In the original article, the authors recommended the combined use of the philosophies of scientific realism and…

Ontological and Epistemic Claims of Realism and Instrumentalism

ERIC Educational Resources Information Center

Lau, Michael Y.

2005-01-01

This article presents comments on "Realism, Instrumentalism, and Scientific Symbiosis: Psychological Theory as a Search for Truth and the Discovery of Solutions" by John T. Cacioppo, Gun R. Semin and Gary G. Berntson. While Lau admires the authors efforts to negotiate symbiosis with seemingly incommensurate realist and instrumentalist positions in…

Response of humpback whales (Megaptera novaeangliae) to ramp-up of a small experimental air gun array.

PubMed

Dunlop, Rebecca A; Noad, Michael J; McCauley, Robert D; Kniest, Eric; Slade, Robert; Paton, David; Cato, Douglas H

2016-02-15

'Ramp-up', or 'soft start', is a mitigation measure used in seismic surveys and involves increasing the radiated sound level over 20-40 min. This study compared the behavioural response in migrating humpback whales to the first stages of ramp-up with the response to a 'constant' source, 'controls' (in which the array was towed but not operated) with groups in the absence of the source vessel used as the 'baseline'. Although the behavioural response, in most groups, resulted in an increase in distance from the source (potential avoidance), there was no evidence that either 'ramp-up' or the constant source at a higher level was superior for triggering whales to move away from the source vessel. 'Control' groups also responded suggesting the presence of the source vessel had some effect. However, the majority of groups appeared to avoid the source vessel at distances greater than the radius of most mitigation zones. Copyright © 2016 Elsevier Ltd. All rights reserved.

New light-gas guns for studying high-velocity impact at space velocities

NASA Astrophysics Data System (ADS)

Khristenko, Yuri F.

2017-10-01

The paper describes new light-gas guns for the high-velocity throwing of different projectiles: an upgraded two-stage light-gas powder gun and single-, two- and three-stage compressed light-gas guns. The paper also provides the schemes, pictures and characteristics of light-gas guns.

46 CFR 160.031-6 - Marking.

Code of Federal Regulations, 2010 CFR

2010-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160.031-6 Marking. (a) Gun. The gun shall be permanently and legibly marked on the barrel with the manufacturer's model or type designation of the gun, the serial number for the gun, the official Coast Guard...

46 CFR 160.031-6 - Marking.

Code of Federal Regulations, 2013 CFR

2013-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160.031-6 Marking. (a) Gun. The gun shall be permanently and legibly marked on the barrel with the manufacturer's model or type designation of the gun, the serial number for the gun, the official Coast Guard...

46 CFR 160.031-6 - Marking.

Code of Federal Regulations, 2012 CFR

2012-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160.031-6 Marking. (a) Gun. The gun shall be permanently and legibly marked on the barrel with the manufacturer's model or type designation of the gun, the serial number for the gun, the official Coast Guard...

46 CFR 160.031-6 - Marking.

Code of Federal Regulations, 2011 CFR

2011-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160.031-6 Marking. (a) Gun. The gun shall be permanently and legibly marked on the barrel with the manufacturer's model or type designation of the gun, the serial number for the gun, the official Coast Guard...

46 CFR 160.031-6 - Marking.

Code of Federal Regulations, 2014 CFR

2014-10-01

...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Line-Throwing Appliance, Shoulder Gun Type (and Equipment) § 160.031-6 Marking. (a) Gun. The gun shall be permanently and legibly marked on the barrel with the manufacturer's model or type designation of the gun, the serial number for the gun, the official Coast Guard...

Experimental Design and Analysis of M1A1 Commander/Gunner Performance during CONOPS (Continuous Operations) Using the U-COFT (Unit Conduct of Fire Trainer)

DTIC Science & Technology

1989-09-01

gun b. 7.62-mm coax manchine gun c. Commander’s weapon station caliber .50 machine gun d. M250 grenade launchers 2. Ammunition Simulation a. 105-mm...7.62-mm machine gun f. M250 smoke grenades 3. Normal Mode Simulation a. Stabilized coax machine gun b. Stabilized main gun c. Commander’s weapon d

Revisiting Pneumatic Nail Gun Trigger Recommendations.

PubMed

Albers, James; Lowe, Brian; Lipscomb, Hester; Hudock, Stephen; Dement, John; Evanoff, Bradley; Fullen, Mark; Gillen, Matt; Kaskutas, Vicki; Nolan, James; Patterson, Dennis; Platner, James; Pompeii, Lisa; Schoenfisch, Ashley

2015-03-01

Use of a pneumatic nail gun with a sequential actuation trigger (SAT) significantly diminishes the risk for acute traumatic injury compared to use of a contact actuation trigger (CAT) nail gun. A theoretically-based increased risk of work-related musculoskeletal disorders from use of a SAT nail gun, relative to CAT, appears unlikely and remains unproven. Based on current knowledge, the use of CAT nail guns cannot be justified as a safe alternative to SAT nail guns. This letter provides a perspective of ergonomists and occupational safety researchers recommending the use of the sequential actuation trigger for all nail gun tasks in the construction industry.

Does the declining lethality of gunshot injuries mask a rising epidemic of gun violence in the United States?

PubMed

Jena, Anupam B; Sun, Eric C; Prasad, Vinay

2014-07-01

Recent mass shootings in the U.S. have reignited the important public health debate concerning measures to decrease the epidemic of gun violence. Editorialists and gun lobbyists have criticized the recent focus on gun violence, arguing that gun-related homicide rates have been stable in the last decade. While true, data from the U.S. Centers for Disease Control and Prevention also demonstrate that although gun-related homicide rates were stable between 2002 and 2011, rates of violent gunshot injuries increased. These seemingly paradoxical trends may reflect the declining lethality of gunshot injuries brought about by surgical advances in the care of the patient with penetrating trauma. Focusing on gun-related homicide rates as a summary statistic of gun violence, rather than total violent gunshot injuries, can therefore misrepresent the rising epidemic of gun violence in the U.S.

Individual-level risk factors for gun victimization in a sample of probationers.

PubMed

Wells, William; Chermak, Steven

2011-07-01

Interventions aimed at preventing the important problem of gun injuries could be improved with an understanding of whether there are unique factors that place individuals at an increased risk of gun victimization. Much remains to be known about the victims of gun violence. The purpose of this article is to assess whether there are individual-level variables uniquely related to the likelihood of experiencing a gun victimization in a sample of probationers, individuals already at a heightened risk for criminal victimization. Self-report data were collected from 235 felony probationers about, for instance, gun and nongun victimization, gang involvement, and drug sales. Results show different variables are related to nongun victimization and gun victimization. In the current sample, involvement in gun crimes are linked to an increased risk of gun victimization. Violent offending and residential stability are associated with an increased chance of crime victimization.

Investigating the link between gun possession and gun assault.

PubMed

Branas, Charles C; Richmond, Therese S; Culhane, Dennis P; Ten Have, Thomas R; Wiebe, Douglas J

2009-11-01

We investigated the possible relationship between being shot in an assault and possession of a gun at the time. We enrolled 677 case participants that had been shot in an assault and 684 population-based control participants within Philadelphia, PA, from 2003 to 2006. We adjusted odds ratios for confounding variables. After adjustment, individuals in possession of a gun were 4.46 (P < .05) times more likely to be shot in an assault than those not in possession. Among gun assaults where the victim had at least some chance to resist, this adjusted odds ratio increased to 5.45 (P < .05). On average, guns did not protect those who possessed them from being shot in an assault. Although successful defensive gun uses occur each year, the probability of success may be low for civilian gun users in urban areas. Such users should reconsider their possession of guns or, at least, understand that regular possession necessitates careful safety countermeasures.

Should gun safety be taught in schools? Perspectives of teachers.

PubMed

Obeng, Cecilia

2010-08-01

Gun-related injuries and deaths among children occur at disproportionately high rates in the United States. Children who live in homes with guns are the most likely victims. This study describes teachers' views on whether gun safety should be taught to children in the preschool and elementary years. A total of 150 survey questionnaires were distributed to public and private school teachers in preschools and elementary schools in 2 counties of a Midwestern state. In total, 62% of the 102 respondents indicated that they favored the teaching of gun safety, while 13% disapproved and 25% had no opinion. Overall, 28.4% of the respondents supported the teaching of gun safety in grades pre-K (pre-kindergarten) through first grade. About 54% indicated that police or trained military personnel should do the teaching of this subject in schools, while 6.9% suggested that teachers should do the teaching. With a majority of the teachers in favor of teaching gun safety in the schools, a larger study should be conducted that explores the introduction of gun safety into the curriculum in preschool through grade 6. Such a study should evaluate the efficacy of teaching gun safety as a measure to prevent gun violence and injuries involving guns.

Implementing Domestic Violence Gun Confiscation Policy in Rural and Urban Communities: Assessing the Perceived Risk, Benefits, and Barriers.

PubMed

Lynch, Kellie R; Logan, T K

2017-07-01

The purpose of this study was to gain a deeper understanding of why communities differing in culture and resources are willing and able to implement gun confiscation as part of a protective order in the absence of a uniform statewide gun law. Specifically, the perceived risk of intimate partner homicide and gun violence, effectiveness of implementing gun confiscation, and the barriers to implementing gun confiscation were assessed. Interviews were conducted with key community professionals ( N = 133) who worked in victim services and the justice system in one urban community and four rural, under-resourced communities. Analyses revealed that professionals in the rural communities viewed the risk of intimate partner homicide and gun violence as lower, and the process of implementing gun confiscation as less effective than professionals in the urban community. In addition, urban justice system professionals, in comparison with all other professionals, reported fewer barriers to enforcing the gun confiscation police and were more likely to downplay law enforcement limitations in the community. The results have implications for developing more effective regional strategies in states that lack domestic violence gun laws as a means to increase a community's ability to enforce gun policies and initiatives.

Marshall Space Flight Center's Impact Testing Facility Capabilities

NASA Technical Reports Server (NTRS)

Evans, Steve; Finchum, Andy; Hubbs, Whitney

2008-01-01

Marshall Space Flight Center's (MSFC) Impact Testing Facility (ITF) serves as an important installation for space and missile related materials science research. The ITF was established and began its research in spacecraft debris shielding in the early 1960% then played a major role in the International Space Station debris shield development. As NASA became more interested in launch debris and in-flight impact concerns, the ITF grew to include research in a variety of impact genres. Collaborative partnerships with the DoD led to a wider range of impact capabilities being relocated to MSFC as a result of the closure of Particle Impact Facilities in Santa Barbara, California. The Particle Impact Facility had a 30 year history in providing evaluations of aerospace materials and components during flights through rain, ice, and solid particle environments at subsonic through hypersonic velocities. The facility's unique capabilities were deemed a "National Asset" by the DoD. The ITF now has capabilities including environmental, ballistic, and hypervelocity impact testing utilizing an array of air, powder, and two-stage light gas guns to accommodate a variety of projectile and target types and sizes. Relocated test equipment was dated and in need of upgrade. Numerous upgrades including new instrumentation, triggering circuitry, high speed photography, and optimized sabot designs have been implemented. Other recent research has included rain drop demise characterization tests to obtain data for inclusion in on-going model development. Future ITF improvements will be focused on continued instrumentation and performance enhancements. These enhancements will allow further, more in-depth, characterization of rain drop demise characterization and evaluation of ice crystal impact. Performance enhancements also include increasing the upper velocity limit of the current environmental guns to allow direct environmental simulation for missile components. The current and proposed ITF capabilities range from rain to micrometeoroids allowing the widest test parameter range possible for materials investigations in support of space, atmospheric, and ground environments. These test capabilities including hydrometeor, single/multi-particle, ballistic gas grins, exploding wire gun, and light gas guns combined with Smooth Particle Hydrodynamics Code (SPHC) simulations represent the widest range of impact test capabilities in the country.

GUN4-Porphyrin Complexes Bind the ChlH/GUN5 Subunit of Mg-Chelatase and Promote Chlorophyll Biosynthesis in Arabidopsis[W

PubMed Central

Adhikari, Neil D.; Froehlich, John E.; Strand, Deserah D.; Buck, Stephanie M.; Kramer, David M.; Larkin, Robert M.

2011-01-01

The GENOMES UNCOUPLED4 (GUN4) protein stimulates chlorophyll biosynthesis by activating Mg-chelatase, the enzyme that commits protoporphyrin IX to chlorophyll biosynthesis. This stimulation depends on GUN4 binding the ChlH subunit of Mg-chelatase and the porphyrin substrate and product of Mg-chelatase. After binding porphyrins, GUN4 associates more stably with chloroplast membranes and was proposed to promote interactions between ChlH and chloroplast membranes—the site of Mg-chelatase activity. GUN4 was also proposed to attenuate the production of reactive oxygen species (ROS) by binding and shielding light-exposed porphyrins from collisions with O2. To test these proposals, we first engineered Arabidopsis thaliana plants that express only porphyrin binding–deficient forms of GUN4. Using these transgenic plants and particular mutants, we found that the porphyrin binding activity of GUN4 and Mg-chelatase contribute to the accumulation of chlorophyll, GUN4, and Mg-chelatase subunits. Also, we found that the porphyrin binding activity of GUN4 and Mg-chelatase affect the associations of GUN4 and ChlH with chloroplast membranes and have various effects on the expression of ROS-inducible genes. Based on our findings, we conclude that ChlH and GUN4 use distinct mechanisms to associate with chloroplast membranes and that mutant alleles of GUN4 and Mg-chelatase genes cause sensitivity to intense light by a mechanism that is potentially complex. PMID:21467578

Sources of guns to dangerous people: what we learn by asking them.

PubMed

Cook, Philip J; Parker, Susan T; Pollack, Harold A

2015-10-01

Gun violence exacts a lethal toll on public health. This paper focuses on reducing access to firearms by dangerous offenders, contributing original empirical data on the gun transactions that arm offenders in Chicago. Conducted in the fall of 2013, analysis of an open-ended survey of 99 inmates of Cook County Jail focuses on a subset of violence-prone individuals with the goal of improving law enforcement actions. Among our principal findings: *Our respondents (adult offenders living in Chicago or nearby) obtain most of their guns from their social network of personal connections. Rarely is the proximate source either direct purchase from a gun store, or theft. *Only about 60% of guns in the possession of respondents were obtained by purchase or trade. Other common arrangements include sharing guns and holding guns for others. *About one in seven respondents report selling guns, but in only a few cases as a regular source of income. *Gangs continue to play some role in Chicago in organizing gun buys and in distributing guns to members as needed. *The Chicago Police Department has a considerable effect on the workings of the underground gun market through deterrence. Transactions with strangers and less-trusted associates are limited by concerns over arrest risk (if the buyer should happen to be an undercover officer or a snitch), and about being caught with a "dirty" gun (one that has been fired in a crime). Copyright © 2015 Elsevier Inc. All rights reserved.

Control of Retrograde Signaling by Rapid Turnover of GENOMES UNCOUPLED11[OPEN

PubMed Central

Chalvin, Camille; Wu, Xu Na

2018-01-01

The exchange of signals between cellular compartments coordinates development and differentiation, modulates metabolic pathways, and triggers responses to environmental conditions. The proposed central regulator of plastid-to-nucleus retrograde signaling, GENOMES UNCOUPLED1 (GUN1), is present at very low levels, which has hampered the discovery of its precise molecular function. Here, we show that the Arabidopsis (Arabidopsis thaliana) GUN1 protein accumulates to detectable levels only at very early stages of leaf development, where it functions in the regulation of chloroplast biogenesis. GUN1 mRNA is present at high levels in all tissues, but GUN1 protein undergoes rapid degradation (with an estimated half-life of ∼4 h) in all tissues where chloroplast biogenesis has been completed. The rapid turnover of GUN1 is controlled mainly by the chaperone ClpC1, suggesting degradation of GUN1 by the Clp protease. Degradation of GUN1 slows under stress conditions that alter retrograde signaling, thus ensuring that the plant has sufficient GUN1 protein. We also find that the pentatricopeptide repeat motifs of GUN1 are important determinants of GUN1 stability. Moreover, overexpression of GUN1 causes an early flowering phenotype, suggesting a function of GUN1 in developmental phase transitions beyond chloroplast biogenesis. Taken together, our results provide new insight into the regulation of GUN1 by proteolytic degradation, uncover its function in early chloroplast biogenesis, and suggest a role in developmental phase transitions. PMID:29367233

State Firearm Laws and Interstate Transfer of Guns in the USA, 2006-2016.

PubMed

Collins, Tessa; Greenberg, Rachael; Siegel, Michael; Xuan, Ziming; Rothman, Emily F; Cronin, Shea W; Hemenway, David

2018-06-01

In a cross-sectional, panel study, we examined the relationship between state firearm laws and the extent of interstate transfer of guns, as measured by the percentage of crime guns recovered in a state and traced to an in-state source (as opposed to guns recovered in a state and traced to an out-of-state source). We used 2006-2016 data on state firearm laws obtained from a search of selected state statutes and 2006-2016 crime gun trace data from the Bureau of Alcohol, Tobacco, Firearms, and Explosives. We examined the relationship between state firearm laws and interstate transfer of guns using annual data from all 50 states during the period 2006-2016 and employing a two-way fixed effects model. The primary outcome variable was the percentage of crime guns recovered in a state that could be traced to an original point of purchase within that state as opposed to another state. The main exposure variables were eight specific state firearm laws pertaining to dealer licensing, sales restrictions, background checks, registration, prohibitors for firearm purchase, and straw purchase of guns. Four laws were independently associated with a significantly lower percentage of in-state guns: a waiting period for handgun purchase, permits required for firearm purchase, prohibition of firearm possession by people convicted of a violent misdemeanor, and a requirement for relinquishment of firearms when a person becomes disqualified from owning them. States with a higher number of gun laws had a lower percentage of traced guns to in-state dealers, with each increase of one in the total number of laws associated with a decrease of 1.6 percentage points in the proportion of recovered guns that were traced to an in-state as opposed to an out-of-state source. Based on an examination of the movement patterns of guns across states, the overall observed pattern of gun flow was out of states with weak gun laws and into states with strong gun laws. These findings indicate that certain state firearm laws are associated with a lower percentage of recovered crime guns being traced to an in-state source, suggesting reduced access to guns in states with those laws.

The Domestic Arms Race.

ERIC Educational Resources Information Center

Caetano, Donald F.

1979-01-01

Discusses the relationship of familial influence, victimization, gun ownership, and attitudes toward gun control. Victims whose parents owned guns are much more likely to own guns and oppose legislation. (JMF)

Free-vibration characteristics of a large split-blanket solar array in a 1-g field

NASA Technical Reports Server (NTRS)

Shaker, F. J.

1976-01-01

Two methods for studying the free vibration characteristics of a large split blanket solar array in both a 0-g and a 1-g cantilevered configuration are presented. The 0-g configuration corresponds to an in-orbit configuration of the array; the 1-g configuration is a typical ground test configuration. The first method applies the equations of continuum mechanics to determine the mode shapes and frequencies of the array; the second method uses the Rayleigh-Ritz approach. In the Rayleigh-Ritz method the array displacements are represented by string modes and cantilevered beam modes. The results of this investigation are summarized by a series of graphs illustrating the effects of various array parameters on the mode shapes and frequencies of the system. The results of the two methods are also compared in tabular form.

Firearms in the home: parental perceptions.

PubMed

Farah, M M; Simon, H K; Kellermann, A L

1999-11-01

Each year, thousands of children are injured or killed from unintentional gunshot wounds. Discovering a gun while playing in the home places children at risk of being injured by the firearm. To determine parental firearm storage practices and parental perceptions of the behavior of their children around guns. Cross-sectional survey of parents of children from 4 to 12 years of age. A sample of 424 parents, bringing their children to one of five pediatric ambulatory care centers, were asked to complete a 20-point self-administered questionnaire at the time of their visit. A total of 400 parents (94%) completed the questionnaire; 113 parents (28%) reported keeping a firearm (most often a handgun) in the home. Firearm owners were predominantly male, 30 years of age or older, white, and married. Of the gun owners, 52% stored their firearms loaded or unlocked, and 13% kept one or more guns loaded and unlocked. Three fourths of gun-owning parents believed that their 4- to 12-year-old child could tell the difference between a toy gun and a real gun, and 23% believed that their child could be trusted with a loaded gun. Although the majority of gun-owning parents (53%) endorsed safe storage as the best firearm injury prevention strategy, 61% of parents who do not own firearms endorse not owning guns as the best way to prevent pediatric firearm injuries. A majority of gun-owning parents store their firearms loaded or unlocked, substantially underestimating the risk of injury to their children. Many firearm-owning parents trust their child with a loaded gun and believe that their young child can tell the difference between a toy gun and a real gun.

A Probabilistic Finite Element Analysis of Residual Stress Formation in Shrink-Fit Ceramic/Steel Gun Barrels

DTIC Science & Technology

2002-01-01

the present work, the Advanced Mean Value method developed by Millwater and co-workers is used [6-10]. II.1.1 Advanced Mean-Value Method The...Engineering A, submitted for publication, December, , 2001. 6. H. R. Millwater and Y.-T. Wu, “Computational Structural Reliability Analysis of a...Turbine Blade,” Proceedings International Gas Turbine and Aeroengine Congress and Exposition, Cincinnati, OH, May 24-27, 1993. 7. Millwater , H.R., Y

Patterns of gun deaths across US counties 1999-2013.

PubMed

Kalesan, Bindu; Galea, Sandro

2017-05-01

We examined the socio-demographic distribution of gun deaths across 3143 counties in 50 United States' states to understand the spatial patterns and correlates of high and low gun deaths. We used aggregate counts of gun deaths and population in all counties from 1999 to 2013 from the Centers for Disease Control and Prevention's Wide-ranging Online Data for Epidemiologic Research (WONDER). We characterized four levels of gun violence, as distinct levels of gun death rates of relatively safe, unsafe, violent, and extremely violent counties, based on quartiles of 15-year county-specific gun death rates per 100,000 and used negative binomial regression models allowing clustering by state to calculate incidence rate ratios and 95% confidence intervals (95% CIs). Most states had at least one violent or extremely violent county. Extremely violent gun counties were mostly rural, poor, predominantly minority, had high unemployment rate and homicide rate. Overall, homicide rate was significantly associated with gun deaths (incidence rate ratios = 1.08, 95% CI = 1.06-1.09). In relatively safe counties, this risk was 1.09 (95% CI = 1.05-1.13) and in extremely violent gun counties was 1.03 (95% CI = 1.03-1.04). There are broad differences in gun death rates across the United States representing different levels of gun death rates in each state with distinct socio-demographic profiles. Copyright © 2017 Elsevier Inc. All rights reserved.

Analysis of magnetically immersed electron guns with non-adiabatic fields

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

Pikin, Alexander; Alessi, James G.; Beebe, Edward N.

Electron diode guns, which have strongly varying magnetic or electric fields in a cathode-anode gap, were investigated in order to generate laminar electron beams with high current density using magnetically immersed guns. By creating a strongly varying radial electric field in a cathode-anode gap of the electron gun, it was demonstrated that the optical properties of the gun can be significantly altered, which allows the generation of a laminar, high-current electron beam with relatively low magnetic field on the cathode. The relatively high magnetic compression of the electron beam achieved by this method is important for producing electron beams withmore » high current density. A similar result can be obtained by inducing a strong variation of the magnetic field in a cathode-anode gap. It was observed that creating a dip in the axial magnetic field in the cathode-anode gap of an adiabatic electron gun has an optical effect similar to guns with strong variation of radial electric field. By analyzing the electron trajectories angles and presenting the results in a gun performance map different geometries of magnetically immersed electron guns with non-adiabatic fields are compared with each other and with a more traditional adiabatic electron gun. Some advantages and limitations of guns with non-adiabatic fields are outlined. In conclusion, the tests results of non-adiabatic electron gun with modified magnetic field are presented.« less

Analysis of magnetically immersed electron guns with non-adiabatic fields

DOE PAGES

Pikin, Alexander; Alessi, James G.; Beebe, Edward N.; ...

2016-11-08

Electron diode guns, which have strongly varying magnetic or electric fields in a cathode-anode gap, were investigated in order to generate laminar electron beams with high current density using magnetically immersed guns. By creating a strongly varying radial electric field in a cathode-anode gap of the electron gun, it was demonstrated that the optical properties of the gun can be significantly altered, which allows the generation of a laminar, high-current electron beam with relatively low magnetic field on the cathode. The relatively high magnetic compression of the electron beam achieved by this method is important for producing electron beams withmore » high current density. A similar result can be obtained by inducing a strong variation of the magnetic field in a cathode-anode gap. It was observed that creating a dip in the axial magnetic field in the cathode-anode gap of an adiabatic electron gun has an optical effect similar to guns with strong variation of radial electric field. By analyzing the electron trajectories angles and presenting the results in a gun performance map different geometries of magnetically immersed electron guns with non-adiabatic fields are compared with each other and with a more traditional adiabatic electron gun. Some advantages and limitations of guns with non-adiabatic fields are outlined. In conclusion, the tests results of non-adiabatic electron gun with modified magnetic field are presented.« less

Gun Theft and Crime.

PubMed

Cook, Philip J

2018-06-01

Some law enforcement officials and other observers have asserted that theft is the primary source of guns to crime. In fact, the role of theft in supplying the guns used in robbery, assault, and murder is unknown, and current evidence provides little guidance about whether an effective program to reduce gun theft would reduce gun violence. The current article analyzes publicly available national data on gun theft together with a unique data set for Chicago. The results tend to support a conclusion that stolen guns play only a minor role in crime. First, publicly available data are used to calculate that thefts are only about 1% of all gun transactions nationwide. Second, an analysis of original data from Chicago demonstrates that less than 3% of crime guns recovered by the police have been reported stolen to the Chicago Police Department (CPD). If a gun is reported stolen, there is a 20% chance that it will be recovered, usually in conjunction with an arrest for illegal carrying. Less than half of those picked up with a stolen gun have a criminal record that includes violent offenses. Third, results from surveys of convicted criminals, both nationally and in Chicago, suggest that it is rare for respondents to have stolen the gun used in their most recent crime. The data on which these results are based have various shortcomings. A research agenda is proposed that would provide more certainty about the role of theft.

Analysis of magnetically immersed electron guns with non-adiabatic fields.

PubMed

Pikin, Alexander; Alessi, James G; Beebe, Edward N; Raparia, Deepak; Ritter, John

2016-11-01

Electron diode guns, which have strongly varying magnetic or electric fields in a cathode-anode gap, were investigated in order to generate laminar electron beams with high current density using magnetically immersed guns. By creating a strongly varying radial electric field in a cathode-anode gap of the electron gun, it was demonstrated that the optical properties of the gun can be significantly altered, which allows the generation of a laminar, high-current electron beam with relatively low magnetic field on the cathode. The relatively high magnetic compression of the electron beam achieved by this method is important for producing electron beams with high current density. A similar result can be obtained by inducing a strong variation of the magnetic field in a cathode-anode gap. It was observed that creating a dip in the axial magnetic field in the cathode-anode gap of an adiabatic electron gun has an optical effect similar to guns with strong variation of radial electric field. By analyzing the electron trajectories angles and presenting the results in a gun performance map, different geometries of magnetically immersed electron guns with non-adiabatic fields are compared with each other and with a more traditional adiabatic electron gun. Some advantages and limitations of guns with non-adiabatic fields are outlined. The tests' results of a non-adiabatic electron gun with modified magnetic field are presented.

Arabidopsis genomes uncoupled 5 (GUN5) mutant reveals the involvement of Mg-chelatase H subunit in plastid-to-nucleus signal transduction

PubMed Central

Mochizuki, Nobuyoshi; Brusslan, Judy A.; Larkin, Robert; Nagatani, Akira; Chory, Joanne

2001-01-01

A plastid-derived signal plays an important role in the coordinated expression of both nuclear- and chloroplast-localized genes that encode photosynthesis-related proteins. Arabidopsis GUN (genomes uncoupled) loci have been identified as components of plastid-to-nucleus signal transduction. Unlike wild-type plants, gun mutants have nuclear Lhcb1 expression in the absence of chloroplast development. We observed a synergistic phenotype in some gun double-mutant combinations, suggesting there are at least two independent pathways in plastid-to-nucleus signal transduction. There is a reduction of chlorophyll accumulation in gun4 and gun5 mutant plants, and a gun4gun5 double mutant shows an albino phenotype. We cloned the GUN5 gene, which encodes the ChlH subunit of Mg-chelatase. We also show that gun2 and gun3 are alleles of the known photomorphogenic mutants, hy1 and hy2, which are required for phytochromobilin synthesis from heme. These findings suggest that certain perturbations of the tetrapyrrole biosynthetic pathway generate a signal from chloroplasts that causes transcriptional repression of nuclear genes encoding plastid-localized proteins. The comparison of mutant phenotypes of gun5 and another Mg-chelatase subunit (ChlI) mutant suggests a specific function for ChlH protein in the plastid-signaling pathway. PMID:11172074

Law enforcement officers' opinions about gun locks: anchors on life jackets?

PubMed Central

Coyne-Beasley, T; Johnson, R

2001-01-01

Objectives—One way law enforcement officers support firearm safety is by promoting the use of gun locks. This investigation examined law enforcement officers' willingness to use gun locks on their own guns, as well as their opinions regarding gun locks in general. Setting—Law enforcement officers from an urban agency in the southern region of the United States. Methods—Free keyed cable gun locks were distributed to all law enforcement officers in one agency who wanted one, and then an anonymous questionnaire survey was conducted about their subsequent use of, and attitudes toward, these devices. Results—About half of the 207 officers collected gun locks (n=103). Nearly three quarters (73%) completed and returned the questionnaire. Two thirds reported that they were not using the gun lock they collected (65%), and over half disagreed that gun lock use should be required (56%). Very few cited any actual or potential technical problems with the device. An important reason given for non-use of gun locks related to being able to access the weapon quickly in case of an emergency. Conclusions—The findings highlight the need for further investigation into law enforcement officers' attitudes toward gun locks, the degree to which their attitudes affect their firearm safety counseling, and the need to develop a gun safety device that can be disengaged quickly. PMID:11565984

Full-color laser cathode ray tube (L-CRT) projector

NASA Astrophysics Data System (ADS)

Kozlovskiy, Vladimir; Nasibov, Alexander S.; Popov, Yuri M.; Reznikov, Parvel V.; Skasyrsky, Yan K.

1995-04-01

A full color TV projector based on three laser cathode-ray tubes (L-CRT) is described. A water-cooled laser screen (LS) is the radiation element of the L-CRT. We have produced three main colors (blue, green and red) by using the LS made of three II-VI compounds: ZnSe ((lambda) equals 475 nm), CdS ((lambda) equals 530 nm) and ZnCdSe (630 nm). The total light flow reaches 1500 Lm, and the number of elements per line is not less than 1000. The LS efficiency may be about 10 Lm/W. In our experiments we have tested new electron optics: - (30 - 37) kV are applied to the cathode unit of the electron gun; the anode of the e-gun and the e-beam intensity modulator are under low potential; the LS has a potential + (30 - 37) kV. The accelerating voltage is divided into two parts, and this enables us to diminish the size and weight of the projector.

Characteristics of combustion flame sprayed nickel aluminum using a Coanda Assisted Spray Manipulation collar for off-normal deposits

NASA Astrophysics Data System (ADS)

Archibald, Reid S.

A novel flame spray collar called the Coanda Assisted Spray Manipulation collar (CSM) has been tested for use on the Sulzer Metco 5P II combustion flame spray gun. A comparison study of the stock nozzle and the CSM has been performed by evaluating the porosity, surface roughness, microhardness, tensile strength and microscopy of normal and off-normal sprayed NiAl deposits. The use of the CSM collar resulted in the need to position the sprayed coupons closer to the gun, which in turn affected the particle impact energy and particle temperatures of the NiAl powder. For the CSM, porosities had a larger scatterband, surface roughness was comparably the same, microhardness was lower, and tensile strength was higher. The microscopy analysis revealed a greater presence of unmelted particles and steeper intersplat boundaries for the CSM. For both processes, the porosity and surface roughness increased and the microhardness decreased as the spray angle decreased.

Alignment Fixtures For Vacuum-Plasma-Spray Gun

NASA Technical Reports Server (NTRS)

Woodford, William H.; Mckechnie, Timothy N.; Power, Christopher A.; Daniel, Ronald L., Jr.

1993-01-01

Fixtures for alignment of vacuum-plasma-spray guns built. Each fixture designed to fit specific gun and holds small, battery-powered laser on centerline of gun. Laser beam projects small red dot where centerline intersects surface of workpiece to be sprayed. After laser beam positioned on surface of workpiece, fixture removed from gun and spraying proceeds.

Gun Sales. Firearm Facts.

ERIC Educational Resources Information Center

Duker, Laurie, Ed.

Minimal federal regulations on firearm sales have facilitated the proliferation of guns, gun owners, and gun dealers in the United States. This fact sheet offers data on the growing number of firearm dealers, the relative ease of obtaining and keeping a license to sell guns from the Federal Bureau of Alcohol, Tobacco, and Firearms, the lack of…

Loaded: Gun involvement among opioid users.

PubMed

Stein, Michael D; Kenney, Shannon R; Anderson, Bradley J; Bailey, Genie L

2018-06-01

Despite ample research examining how alcohol use relates to gun involvement, little is known about the relationship between opioids and gun involvement. In the current study, we examined correlates of gun possession, accessibility, and related behaviors in an opioid dependent sample. Between October 2016 and April 2017, we surveyed persons entering a brief, inpatient opioid detoxification (n = 386) and 51 contemporaneous persons seeking alcohol detoxification at the same facility in Massachusetts and recorded their lifetime experiences with gun involvement. Participants averaged 33 years of age, 74% were male, 83% were White, and 64% had a history of incarceration. Opioid users had significantly higher rates of gun involvement than persons in alcohol detoxification; for example, 31.3% (vs. 3.9%) had carried a gun for protection, 45.1% (vs. 25.5%) had been threatened with a gun, and 13.8% (vs. 2.0%) had shot at another person. Among persons misusing opioids, male and non-White respondents, and those with a history of incarceration or poorer self-control reported greater gun involvement. Opioid users, both men and women, lead gun-involved lives. Copyright © 2018 Elsevier B.V. All rights reserved.

Ultra-thin g-C{sub 3}N{sub 4} nanosheets wrapped silicon nanowire array for improved chemical stability and enhanced photoresponse

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

Wang, Beibei; Yu, Hongtao; Quan, Xie, E-mail: quanxie@dlut.edu.cn

2014-11-15

Highlights: • g-C{sub 3}N{sub 4}, as an oxygen free and metal free protective material for Si, was proposed. • g-C{sub 3}N{sub 4} nanosheets wrapped Si nanowire array was synthesized. • SiNW/g-C{sub 3}N{sub 4} exhibited enhancement of photoelectrochemical stability and photocurrent. - Abstract: In order to inhibit the oxidation of Si materials in aqueous solution, Si nanowire array was wrapped by ultra-thin g-C{sub 3}N{sub 4} nanosheets via an electrophoresis process. Scanning electron microscopy and transmission electron microscopy images showed that g-C{sub 3}N{sub 4} nanosheets were evenly distributed on the surface of Si nanowire array. X-ray diffraction patterns indicated that Si nanowiremore » array/g-C{sub 3}N{sub 4} nanosheets were composed of Si (4 0 0 crystal plane) and g-C{sub 3}N{sub 4} (0 0 2 and 1 0 0 crystal planes). The cyclic voltammetry curves revealed that the corrosion of Si nanowire array was restrained under the protection of g-C{sub 3}N{sub 4} nanosheets. Furthermore, the photocurrent density of Si nanowire array/g-C{sub 3}N{sub 4} nanosheets increased by nearly 3 times compared to that of bare Si nanowire array due to the effective charge separation caused by the built-in electric field at the interface. This work will facilitate the applications of Si materials in aqueous solution, such as solar energy harvest and photocatalytic pollution control.« less

24-71 GHz PCB Array for 5G ISM

NASA Technical Reports Server (NTRS)

Novak, Markus H.; Volakis, John L.; Miranda, Felix A.

2017-01-01

Millimeter-wave 5G mobile architectures need to consolidate disparate frequency bands into a single, multifunctional array. Existing arrays are either narrow-band, prohibitively expensive or cannot be scaled to these frequencies. In this paper, we present the first ultra-wideband millimeter wave array to operate across six 5G and ISM bands spanning 24-71 GHz. Importantly, the array is realized using low-cost PCB. The paper presents the design and optimized layout, and discusses fabrication and measurements.

RF Conditioning of the Photo-Cathode RF Gun at the Advanced Photon Source - NWA RF Measurements

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

Smith, T. L.; DiMonte, N.; Nassiri, A.

A new S-band Photo-cathode (PC) gun was recently installed and RF conditioned at the Advanced Photon Source (APS) Injector Test-stand (ITS) at Argonne National Lab (ANL). The APS PC gun is a LCLS type gun fabricated at SLAC [1]. The PC gun was delivered to the APS in October 2013 and installed in the APS ITS in December 2013. At ANL, we developed a new method of fast detection and mitigation of the guns internal arcs during the RF conditioning process to protect the gun from arc damage and to RF condition more efficiently. Here, we report the results ofmore » RF measurements for the PC gun and an Auto-Restart method for high power RF conditioning.« less

From gun politics to self-defense politics: a feminist critique of the great gun debate.

PubMed

Carlson, Jennifer D

2014-03-01

This article calls attention to a problematic binary produced by public debates surrounding gun rights and gun control-namely, that women must choose armed self-protection or no self-protection at all. I argue that both anti- and pro-gun discourses, drawing on and reproducing race and class privileges, use assumptions about women's physical inferiority to further their agendas. I highlight how both sides have used guns as the proxy for self-defense and conclude by calling for a shift in public discourse to focus on the broader question of the right to self-defense rather than the narrower question of gun rights.

Revisiting Pneumatic Nail Gun Trigger Recommendations

PubMed Central

Albers, James; Lipscomb, Hester; Hudock, Stephen; Dement, John; Evanoff, Bradley; Fullen, Mark; Gillen, Matt; Kaskutas, Vicki; Nolan, James; Patterson, Dennis; Platner, James; Pompeii, Lisa; Schoenfisch, Ashley

2015-01-01

Summary Use of a pneumatic nail gun with a sequential actuation trigger (SAT) significantly diminishes the risk for acute traumatic injury compared to use of a contact actuation trigger (CAT) nail gun. A theoretically-based increased risk of work-related musculoskeletal disorders from use of a SAT nail gun, relative to CAT, appears unlikely and remains unproven. Based on current knowledge, the use of CAT nail guns cannot be justified as a safe alternative to SAT nail guns. This letter provides a perspective of ergonomists and occupational safety researchers recommending the use of the sequential actuation trigger for all nail gun tasks in the construction industry. PMID:26366020

Gun policy and serious mental illness: priorities for future research and policy.

PubMed

McGinty, Emma Elizabeth; Webster, Daniel W; Barry, Colleen L

2014-01-01

In response to recent mass shootings, policy makers have proposed multiple policies to prevent persons with serious mental illness from having guns. The political debate about these proposals is often uninformed by research. To address this gap, this review article summarizes the research related to gun restriction policies that focus on serious mental illness. Gun restriction policies were identified by researching the THOMAS legislative database, state legislative databases, prior review articles, and the news media. PubMed, PsycINFO, and Web of Science databases were searched for publications between 1970 and 2013 that addressed the relationship between serious mental illness and violence, the effectiveness of gun policies focused on serious mental illness, the potential for such policies to exacerbate negative public attitudes, and the potential for gun restriction policies to deter mental health treatment seeking. Limited research suggests that federal law restricting gun possession by persons with serious mental illness may prevent gun violence from this population. Promotion of policies to prevent persons with serious mental illness from having guns does not seem to exacerbate negative public attitudes toward this group. Little is known about how restricting gun possession among persons with serious mental illness affects suicide risk or mental health treatment seeking. Future studies should examine how gun restriction policies for serious mental illness affect suicide, how such policies are implemented by states, how persons with serious mental illness perceive policies that restrict their possession of guns, and how gun restriction policies influence mental health treatment seeking among persons with serious mental illness.

Improving firearm storage in Alaska native villages: a randomized trial of household gun cabinets.

PubMed

Grossman, David C; Stafford, Helen A; Koepsell, Thomas D; Hill, Ryan; Retzer, Kyla D; Jones, Ward

2012-05-01

We determined if the installation of gun cabinets improved household firearm storage practices. We used a wait list, randomized trial design with 2 groups. The "early" group received the intervention at baseline, and the "late" group received it at 12 months. Up to 2 gun cabinets were installed in each enrolled home, along with safety messages. In-person surveys were conducted at 12 and 18 months to determine the proportion of households reporting unlocked guns or ammunition. Direct observations of unlocked guns were also compared. At baseline, 93% of homes reported having at least 1 unlocked gun in the home, and 89% reported unlocked ammunition. At 12 months, 35% of homes in the early group reported unlocked guns compared with 89% in the late group (P < .001). Thirty-six percent of the early homes reported unlocked ammunition compared with 84% of late homes (P < .001). The prevalence of these storage practices was maintained at 18 months. Observations of unlocked guns decreased significantly (from 20% to 8%) between groups (P < .03). Gun cabinet installation in rural Alaskan households improved the storage of guns and ammunition. If these gains are sustained over time, it may lead to a reduction in gun-related injuries and deaths in this population.

Effects of undercover police stings of gun dealers on the supply of new guns to criminals

PubMed Central

Webster, D W; Bulzacchelli, M T; Zeoli, A M; Vernick, J S

2006-01-01

Objective To assess the effects of undercover police stings and lawsuits against gun dealers suspected of facilitating illegal gun sales in three US cities (Chicago, Detroit, Gary) on the flow of new firearms to criminals. Methods An interrupted time series design and negative binomial regression analyses were used to test for temporal change in the recovery of guns used in crimes within one year of retail sale in both intervention and comparison cities. Results The stings were associated with an abrupt 46.4% reduction in the flow of new guns to criminals in Chicago (95% confidence interval, −58.6% to −30.5%), and with a gradual reduction in new crime guns recovered in Detroit. There was no significant change associated with the stings in Gary, and no change in comparison cities that was coincident with the stings in Chicago and Detroit. Conclusions The announcement of police stings and lawsuits against suspect gun dealers appeared to have reduced the supply of new guns to criminals in Chicago significantly, and may have contributed to beneficial effects in Detroit. Given the important role that gun stores play in supplying guns to criminals in the US, further efforts of this type are warranted and should be evaluated. PMID:16887943

Survey of SRF guns

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

Belomestnykh, S.

Developing Superconducting RF (SRF) electron guns is an active field with several laboratories working on different gun designs. While the first guns were based on elliptic cavity geometries, Quarter Wave Resonator (QWR) option is gaining popularity. QWRs are especially well suited for producing beams with high charge per bunch. In this talk we will describe recent progress in developing both types of SRF guns. SRF guns made excellent progress in the last two years. Several guns generated beams and one, at HZDR, injected beam into an accelerator. By accomplishing this, HZDR/ELBE gun demonstrated feasibility of the SRF gun concept withmore » a normal-conducting Cs{sub 2}Te cathode. The cathode demonstrated very good performance with the lifetime of {approx}1 year. However, for high average current/high bunch charge operation CsK{sub 2}Sb is preferred as it needs green lasers, unlike UV laser for the Cs{sub 2}Te, which makes it easier to build laser/optics systems. Other high QE photocathodes are being developed for SRF guns, most notably diamond-amplified photocathode. Several QWR guns are under development with one producing beam already. They are very promising for high bunch charge operation. The field is very active and we should expect more good results soon.« less

Regulation of firearm dealers in the United States: an analysis of state law and opportunities for improvement.

PubMed

Vernick, Jon S; Webster, Daniel W; Bulzacchelli, Maria T; Mair, Julie Samia

2006-01-01

Firearms were associated with 30, 136 deaths in the United States in 2003. Most guns are initially sold to the public through a network of retail dealers. Licensed firearm dealers are an important source of guns for criminals and gun traffickers. Just one percent of licensed dealers were responsible for more than half of all guns traced to crime. Federal law makes it difficult for ATF to inspect and revoke the licenses of problem gun dealers. State licensing systems, however, are a greatly under-explored opportunity for firearm dealer oversight. We identify and categorize these state systems to identify opportunities for interventions to prevent problem dealers from supplying guns to criminals, juveniles, or gun traffickers. Just seventeen states license gun dealers. Twenty-three states permit routine inspections of dealers but only two mandate that those inspections occur on a regular basis. Twenty-six states impose record-keeping requirements for gun sales. Only thirteen states require some form of store security measures to minimize firearm theft. We conclude with recommendations for a comprehensive system of state licensing and oversight of gun dealers. Our findings can be useful for the coalition of more than fifty U.S. mayors that recently announced it would work together to combat illegal gun trafficking.

Shock Equation of State of Multi-Phase Epoxy-Based Composite (Al-MnO2-Epoxy)

DTIC Science & Technology

2010-10-01

single stage light gas gun , two...using three different loading techniques— single stage light gas gun , two stage light gas gun , and explosive loading—with multiple diagnostic...wave speed. B. Single stage gas gun loading experiments Four gas gun -driven equation of state experiments were conducted at NSWC-Indian Head using

Ready, Fire, Aim: The College Campus Gun Fight

ERIC Educational Resources Information Center

Birnbaum, Robert

2013-01-01

The question of whether guns should be permitted on college and university campuses in the United States reflects the tension between two competing perspectives. America has both a robust gun culture and an equally robust (if less well known) gun-control culture. The gun culture is as American as apple pie: There may be as many as 300 million…

Gun Safety Management with Patients at Risk for Suicide

ERIC Educational Resources Information Center

Simon, Robert I.

2007-01-01

Guns in the home are associated with a five-fold increase in suicide. All patients at risk for suicide must be asked if guns are available at home or easily accessible elsewhere, or if they have intent to buy or purchase a gun. Gun safety management requires a collaborative team approach including the clinician, patient, and designated person…

Microwave scanning beam approach and landing system phased array antenna : volume II

DOT National Transportation Integrated Search

1973-02-01

The use of phased arrays for the proposed landing system (MLS) is discussed. Studies relating to ground reflections, near field focusing, and phased-array errors are presented. Two experimental antennas which were fabricated and tested are described....

Adolescent gun violence prevention: what we know, and what we can do to keep young people safe.

PubMed

Dodson, Nancy A

2016-08-01

This review will focus on recent research, initiatives, and legislation regarding the issue of gun violence as it pertains to adolescents. Homicide and suicide continue to be major killers of adolescents in the United States. Gun homicide kills teens in the most urban areas of the United States at the same rate as suicide kills teens in the most rural areas of the United States. Research on assault-injured youth sheds light on risk factors for teen gun homicide, and has found high rates of illegal gun carrying and retaliatory attitudes among at-risk teens. Suicide research continues to show a strong correlation between gun ownership and accessibility, and risk of completed suicide. Stand Your Ground laws and campus carry laws present unique threats to different populations of American teens. Given the enormous toll that gun violence takes on adolescent lives, pediatricians should ask about guns in the home and become involved in efforts to strengthen laws that would decrease gun violence.

Screening the ToxCast Phase II library for acute neurotoxicity using cortical neurons grown on multi-well microelectrode array (mwMEA) plates

EPA Science Inventory

We have used primary cortical neurons grown in multi-well microelectrode array (mwMEA) plates to screen the ToxCast Phase II library of 1055 unique compounds for the ability to cause acute neurotoxicity. Each compound was screened at a single high concentration of 40 µM...

50 CFR 92.20 - Methods and means.

Code of Federal Regulations, 2010 CFR

2010-10-01

... birds: (a) Swivel guns, shotguns larger than 10 gauge, punt guns, battery guns, machine guns, fish hooks... traditional means of harvesting auklets on Diomede and St. Lawrence islands.); (e) Hunting with the aid of...

Design and development of a 40 kV pierce electron gun

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

Bhattacharjee, D.; Tiwari, R.; Jayaprakash, D., E-mail: dhruva.bhattacharjee@gmail.com

A 40 kV electron gun is designed and developed using the Pierce configuration for the focusing electrode. Simulations were carried out using CST Particle Studio. The Gun is a thermionic type electron gun with indirect heating of the LaB6 cathode. The gun is capable of delivering a beam current of more than 500 mA at 40 kV with a beam size of less than 5 mm. The cathode assembly consists of cups and heat shields made out of Tantalum and Rhenium sheets. The cathode assembly and the electron gun was fabricated, assembled and tested on test bench for cathode conditioning,more » HV conditioning and beam characterization. This paper presents the gun design, particle simulations study, testing of the gun on test bench. (author)« less

Large-area thin self-supporting carbon foils with MgO coatings

NASA Astrophysics Data System (ADS)

Stolarz, Anna; Maier-Komor, Peter

2002-03-01

Large area self-supporting carbon foils in the thickness of range of 8-22 μg/cm 2, coated with approximately 4 μg/cm 2 MgO have been prepared by e-gun evaporation. They were mounted on frames with apertures of 130 cm 2. Problems related to the parting agent preparation, floating procedure, and mounting onto frames are discussed. Special precautions necessary to avoid damage during foil drying, storage and transportation are suggested.

Efficiency of Particle-Bombardment-Mediated Transformation Is Influenced by Cell Cycle Stage in Synchronized Cultured Cells of Tobacco 1

PubMed Central

Iida, Asako; Yamashita, Toshiya; Yamada, Yasuyuki; Morikawa, Hiromichi

1991-01-01

Plasmid DNA pB1221 harboring β-glucuronidase gene was delivered to synchronized cultured tobacco (Nicotiana tabacum L. cv Bright Yellow-2) cells of different cell cycle stages by a pneumatic particle gun. The cells bombarded at M and G2 phases gave 4 to 6 times higher transformation efficiency than those bombarded at the S and G1 phases. ImagesFigure 2 PMID:16668589

Laboratory simulation of intact capture of cometary and asteroidal dust particles in ISAS

NASA Technical Reports Server (NTRS)

Fujiwara, A.; Nakamura, A.; Kadono, T.

1994-01-01

In order to develop a collector for intact capturing of cometary dust particles in the SOCCER mission and regolith dust particles released from asteroid surfaces by the impact of projectiles launched from a flying-by spacecraft, various kinds of materials as the collector candidates have been exposed to hypervelocity projectiles in our laboratory. Data based on the penetration characteristics of various materials (penetration depth, hole profile, effectiveness for intact capturing) are greatly increased. The materials tested for these simulation experiments include various kinds of low-density media and multisheet stacks; these are foamed plastics (polystyrene 0.01 g/cc), silica aerogels (0.04 g/cc), air (0.001 g/cc), liquid, and multisheet stack consisting of thin Al sheets (thickness 0.002 to 0.1 mm) or polyethylene sheets. Projectiles used are spheres or cylinders of nylon, polycarbonate, basalt, copper, iron, and volatile organics (e.g.,paradichlorobenzene) of size ranging from 30 micrometers to 1 cm launched by a two-stage light gas gun and a rail gun in ISAS at velocity up to about 7 km/s. Some results obtained by using nylon projectiles of velocity less than about 5 km/s are presented; the penetration depth vs. bulk density of the collector material for several kinds of materials and the velocity at which the projectiles begin to fragment vs. material density for foamed polystyrene.

Automatic targeting of plasma spray gun

DOEpatents

Abbatiello, Leonard A.; Neal, Richard E.

1978-01-01

A means for monitoring the material portion in the flame of a plasma spray gun during spraying operations is provided. A collimated detector, sensitive to certain wavelengths of light emission, is used to locate the centroid of the material with each pass of the gun. The response from the detector is then relayed to the gun controller to be used to automatically realign the gun.

Performance of a carbon nanotube field emission electron gun

NASA Astrophysics Data System (ADS)

Getty, Stephanie A.; King, Todd T.; Bis, Rachael A.; Jones, Hollis H.; Herrero, Federico; Lynch, Bernard A.; Roman, Patrick; Mahaffy, Paul

2007-04-01

A cold cathode field emission electron gun (e-gun) based on a patterned carbon nanotube (CNT) film has been fabricated for use in a miniaturized reflectron time-of-flight mass spectrometer (RTOF MS), with future applications in other charged particle spectrometers, and performance of the CNT e-gun has been evaluated. A thermionic electron gun has also been fabricated and evaluated in parallel and its performance is used as a benchmark in the evaluation of our CNT e-gun. Implications for future improvements and integration into the RTOF MS are discussed.

Development And Characterization Of A Liner-On-Target Injector For Staged Z-Pinch Experiments

NASA Astrophysics Data System (ADS)

Valenzuela, J. C.; Conti, F.; Krasheninnikov, I.; Narkis, J.; Beg, F.; Wessel, F. J.; Rahman, H. U.

2016-10-01

We present the design and optimization of a liner-on-target injector for Staged Z-pinch experiments. The injector is composed of an annular high atomic number (e.g. Ar, Kr) gas-puff and an on-axis plasma gun that delivers the ionized deuterium target. The liner nozzle injector has been carefully studied using Computational Fluid Dynamics (CFD) simulations to produce a highly collimated 1 cm radius gas profile that satisfies the theoretical requirement for best performance on the 1 MA Zebra current driver. The CFD simulations produce density profiles as a function of the nozzle shape and gas. These profiles are initialized in the MHD MACH2 code to find the optimal liner density for a stable, uniform implosion. We use a simple Snowplow model to study the plasma sheath acceleration in a coaxial plasma gun to help us properly design the target injector. We have performed line-integrated density measurements using a CW He-Ne laser to characterize the liner gas and the plasma gun density as a function of time. The measurements are compared with models and calculations and benchmarked accordingly. Advanced Research Projects Agency - Energy, DE-AR0000569.

Relationship between Attributional Errors and At-Risk Behaviors among Juvenile Delinquents.

ERIC Educational Resources Information Center

Daley, Christine E.; Onwuegbuzie, Anthony J.

The purpose of this study was to determine whether at-risk behaviors (e.g., substance abuse, gun ownership, sexual activity, and gang membership) are associated with violence attribution errors, as measured by Daley and Onwuegbuzie's (1995) Violence Attribution Survey, among 82 incarcerated male juvenile delinquents. Analysis revealed that the…

Youth Attitude Tracking Study. Volume 1. Spring 1979.

DTIC Science & Technology

1979-08-01

2.5 .3 + .5 no " Men with guns . 1 .2 + .1 no m Slogans (e.g., Navy Makes Boys Into Men) .1 .2 + .1 no Men with...survey. Thank you. TO HAKE THIS A VALID INTERVIEW, PLEASE RECORD THE TA, STATE AND COUNTY NUNBER FRON YOUR CALL RECORD PORN . (TA) (STATE

27 CFR 478.112 - Importation by a licensed importer.

Code of Federal Regulations, 2010 CFR

2010-04-01

...) The type (e.g., rifle, shotgun, pistol, revolver and, in the case of ammunition only, ball, wadcutter, shot, etc.); (C) The caliber, gauge, or size; (D) The model; (E) The barrel length, if a firearm or... statement describing such intended use; or (C) If an unserviceable firearm (other than a machine gun) being...

27 CFR 478.113 - Importation by other licensees.

Code of Federal Regulations, 2010 CFR

2010-04-01

...) The type (e.g., rifle, shotgun, pistol, revolver and, in the case of ammunition only, ball, wadcutter, shot, etc.); (C) The caliber, gauge, or size; (D) The model; (E) The barrel length, if a firearm or... machine gun) being imported as a curio or museum piece, a description of how it was rendered unserviceable...

Does Copying Idioms Promote Their Recall?

ERIC Educational Resources Information Center

Stengers, Hélène; Deconinck, Julie; Boers, Frank; Eyckmans, June

2016-01-01

This paper reports an experiment designed to evaluate an attempt to improve the effectiveness of an existing L2 idiom-learning tool. In this tool, learners are helped to associate the abstract, idiomatic meaning of expressions such as "jump the gun" (act too soon) with their original, concrete meaning (e.g. associating "jump the…

Youth Violence: Lessons from the Experts.

ERIC Educational Resources Information Center

Rinehart, P. Mann; Borowsky, I.; Stolz, A.; Latts, E.; Cart, C. U.; Brindis, C. D.

This monograph summarizes what is known about youth and violence, identifying 10 myths that confound people's understanding of the real causes of youth violence. It focuses on: what contributes to youth violence (e.g., children exposed to domestic violence are at risk of using violence, children and adolescents use guns when they are easily…

Hybrid Ultra-Low VOC and Non-HAP Rain Erosion Coatings

DTIC Science & Technology

2018-01-12

cavitation test stand for running the modified ASTM G32 method...Objective Numerous military aircraft and shipboard surfaces, such as radomes, antennas, gun shields, wing leading edges, and helicopter blade leading edges... blades , and helicopter blade leading edges. The application market is extremely widespread. Luna will leverage existing internal contacts for

40 CFR 63.5734 - What standards must I meet for resin and gel coat application equipment cleaning operations?

Code of Federal Regulations, 2010 CFR

2010-07-01

...? (a) For routine flushing of resin and gel coat application equipment (e.g., spray guns, flowcoaters... and gel coat application equipment cleaning operations? 63.5734 Section 63.5734 Protection of... Pollutants for Boat Manufacturing Standards for Resin and Gel Coat Application Equipment Cleaning Operations...

Reactive magnetron sputtering of N-doped carbon thin films on quartz glass for transmission photocathode applications

NASA Astrophysics Data System (ADS)

Balalykin, N. I.; Huran, J.; Nozdrin, M. A.; Feshchenko, A. A.; Kobzev, A. P.; Sasinková, V.; Boháček, P.; Arbet, J.

2018-03-01

N-doped carbon thin films were deposited on a silicon substrate and quartz glass by RF reactive magnetron sputtering using a carbon target and an Ar+N2 gas mixture. During the magnetron sputtering, the substrate holder temperatures was kept at 800 °C. The carbon film thickness on the silicon substrate was about 70 nm, while on the quartz glass it was in the range 15 nm – 60 nm. The elemental concentration in the films was determined by RBS and ERD. Raman spectroscopy was used to evaluate the intensity ratios I D/I G of the D and G peaks of the carbon films. The transmission photocathodes prepared were placed in the hollow-cathode assembly of a Pierce-structure DC gun to produce photoelectrons. The quantum efficiency (QE) was calculated from the laser energy and cathode charge measured. The properties of the transmission photocathodes based on semitransparent N-doped carbon thin films on quartz glass and their potential for application in DC gun technology are discussed.

A Single-Phase Analytic Equation of State for Solid Polyurea and Polyurea Aerogels

NASA Astrophysics Data System (ADS)

Whitworth, Nicholas; Lambourn, Brian

2017-06-01

Commercially available polymers are commonly used as impactors in high explosive gas-gun experiments. This paper presents a relatively simple, single-phase, analytic equation of state (EoS) for solid polyurea and polyurea aerogels suitable for use in hydrocode simulations. An exponential shock velocity-particle velocity relation is initially fit to available Hugoniot data on the solid material, which has a density of 1.13 g/cm3. This relation is then converted to a finite strain relation along the principal isentrope, which is used as the reference curve for a Mie-Gruneisen form of EoS with an assumed form for the variation of Gruneisen Γ with specific volume. Using the solid EoS in conjunction with the Snowplough model for porosity, experimental data on the shock response of solid polyurea and polyurea aerogels with initial densities of 0.20 and 0.35 g/cm3 can be reproduced to a reasonable degree of accuracy. A companion paper at this conference describes the application of this and other EoS in modelling shock-release-reshock gas-gun experiments on the insensitive high explosive PBX 9502.

The Relationships Among Exposure to Violence, Psychological Distress, and Gun Carrying Among Male Adolescents Found Guilty of Serious Legal Offenses: A Longitudinal Cohort Study.

PubMed

Reid, Joan A; Richards, Tara N; Loughran, Thomas A; Mulvey, Edward P

2017-03-21

Gun violence and psychological problems are often conflated in public discourse on gun safety. However, few studies have empirically assessed the effect of exposure to violence when exploring the association between gun carrying and psychological distress. To examine the potential effect of exposure to violence on the associations between gun carrying and psychological distress among vulnerable adolescents. Longitudinal cohort study. The Pathways to Desistance study, a study of youths found guilty of a serious criminal offense in Philadelphia County, Pennsylvania, or Maricopa County, Arizona. 1170 male youths aged 14 to 19 years who had been found guilty of a serious criminal offense. Youths were assessed at baseline and at four 6-month intervals with regard to gun carrying ("Have you carried a gun?"), psychological distress (Global Severity Index), and exposure to violence (modified version of the Exposure to Violence Inventory). At the bivariate level, gun carrying was consistently associated with higher levels of psychological distress. However, the association between psychological distress and gun carrying diminished or disappeared when exposure to violence was considered. Exposure to violence (as either a victim or a witness) was significantly related to gun carrying at all follow-up assessments, with increased odds of gun carrying ranging from 1.43 to 1.87 with each additional report of exposure to violence. The study sample was limited to justice-involved male youths. Precarrying distress and exposure to violence could not be fully captured because many participants had initiated gun carrying before baseline. In male youths involved in the criminal justice system, the relationship between psychological distress and gun carrying seems to be influenced by exposure to violence (either experiencing or witnessing it). Further study is warranted to explore whether interventions after exposure to violence could reduce gun carrying in this population. None.

Guns in young hands: a survey of urban teenagers' attitudes and behaviors related to handgun violence.

PubMed

Bergstein, J M; Hemenway, D; Kennedy, B; Quaday, S; Ander, R

1996-11-01

To determine the nature and causes of gun violence among urban young people. We conducted a confidential survey of 1,219 7th and 10th graders in Boston and Milwaukee, regarding their attitudes and behaviors toward violence and handguns. Twenty-nine percent have had a member of their immediate family shot, 42% could get a gun if they wanted, 28% have handled a gun without adult knowledge or supervision, 17% have carried a concealed gun, and 3% reported bringing a gun to school in the past 30 days. Nine percent admitted smoking cigarettes in the past week, 11% admitted smoking marijuana. Twenty-five percent were attacked or threatened within the past year. Reasons for gun carrying were mostly related to perceived safety/threats/revenge (73%), followed by casual handling (17%), hunting (4%), being cool (3%), target practice (2%), and gangs (1%). The following factors were significantly correlated with gun handling by chi 2 analysis, at p < 0.001 (percentage of respondents admitting unsupervised gun handling shown in parentheses): male (39%) versus female (19%); 10th graders (35%) versus 7th graders (24%) seat-belt nonusers (35%) versus users (20%); students who state they have poor grades (39%) versus good grades (26%); cigarette smokers (61%) versus nonsmokers (25%); have a gun in the home (46%) versus no gun in the home (23%). Also strongly correlated in multivariate analysis were violence exposure, having been arrested, and beliefs that "gun carrying is a good idea," or that "only cowards back down from a fight." Handgun availability and use are high among urban youth; gun carrying is mostly related to safety concerns and easy access, rather than to hunting or sport. This may be a cause of high handgun injury rates in this group. Gun injury prevention programs must address youth safety concerns along with handgun availability.

Selling a gun to a stranger without a background check: acceptable behaviour?

PubMed

Hemenway, David; Azrael, Deborah; Miller, Matthew

2018-06-01

One way that guns get into the wrong hands is via gun sales without a background check. While the large majority of Americans support laws requiring universal background checks, no prior study has assessed whether Americans think it is acceptable behaviour to sell a gun to a stranger without a background check, whether or not there is a law against it. We sponsored a nationally representative survey of over 3900 American adults, oversampling gun owners, using an online panel provided by the survey firm Growth for Knowledge. Over 72% of American adults agree or strongly agree with the statement that 'whether it is legal or not, it is NOT acceptable to sell a gun to a stranger without a background check' and 11% disagree or strongly disagree. Subgroups less likely to agree are young adults, men, conservatives, those with less than a high school education and gun owners. Reducing the number of guns sold without a background check could help reduce the flow of guns to felons. Changes in normative attitudes and behaviours, as well as changes in law, could help accomplish this goal. Most Americans, including gun owners, believe selling a gun to a stranger without a background check is not acceptable behaviour. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Design and Fabrication of Two-Dimensional Semiconducting Bolometer Arrays for the High Resolution Airborne Wideband Camera (HAWC) and the Submillimeter High Angular Resolution Camera II (SHARC-II)

NASA Technical Reports Server (NTRS)

Voellmer, George M.; Allen, Christine A.; Amato, Michael J.; Babu, Sachidananda R.; Bartels, Arlin E.; Benford, Dominic J.; Derro, Rebecca J.; Dowell, C. Darren; Harper, D. Al; Jhabvala, Murzy D.

2002-01-01

The High resolution Airborne Wideband Camera (HAWC) and the Submillimeter High Angular Resolution Camera II (SHARC II) will use almost identical versions of an ion-implanted silicon bolometer array developed at the National Aeronautics and Space Administration's Goddard Space Flight Center (GSFC). The GSFC 'Pop-up' Detectors (PUD's) use a unique folding technique to enable a 12 x 32-element close-packed array of bolometers with a filling factor greater than 95 percent. A kinematic Kevlar(trademark) suspension system isolates the 200 mK bolometers from the helium bath temperature, and GSFC - developed silicon bridge chips make electrical connection to the bolometers, while maintaining thermal isolation. The JFET preamps operate at 120 K. Providing good thermal heat sinking for these, and keeping their conduction and radiation from reaching the nearby bolometers, is one of the principal design challenges encountered. Another interesting challenge is the preparation of the silicon bolometers. They are manufactured in 32-element, planar rows using Micro Electro Mechanical Systems (MEMS) semiconductor etching techniques, and then cut and folded onto a ceramic bar. Optical alignment using specialized jigs ensures their uniformity and correct placement. The rows are then stacked to create the 12 x 32-element array. Engineering results from the first light run of SHARC II at the Caltech Submillimeter Observatory (CSO) are presented.

Gun Safety

MedlinePlus

Many U.S. households have guns, but they can cause harm if not handled properly. Here are some things you can do to keep yourself and ... safe: Teach children that they shouldn't touch guns and that if they see a gun, to ...

Gun utopias? Firearm access and ownership in Israel and Switzerland

PubMed Central

Rosenbaum, Janet

2011-01-01

The 2011 attempted assassination of a US representative renewed the national gun control debate. Gun advocates claim that mass-casualty events are mitigated and deterred with three policies: (1) permissive gun laws, (2) widespread gun ownership, (3) encouragement of armed civilians who can intercept shooters, and cite Switzerland and Israel as exemplars. We evaluate these claims with analysis of International Crime Victimization Survey (ICVS) data and translation of laws and original source material. Swiss and Israeli laws limit firearm ownership and require permit renewal 14 times annually. ICVS analysis finds that the US has more firearms per capita and per household than either country. Switzerland and Israel curtail off-duty soldiers firearm access to prevent firearm deaths. Suicide among soldiers decreased by 40% after the Israeli armys 2006 reforms. Compared with the US, Switzerland and Israel have lower gun ownership and stricter gun laws, and their policies discourage personal gun ownership. PMID:22089893

An X-Band Gun Test Area at SLAC

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

Limborg-Deprey, C.; Adolphsen, C.; Chu, T.S.

The X-Band Test Area (XTA) is being assembled in the NLCTA tunnel at SLAC to serve as a test facility for new RF guns. The first gun to be tested will be an upgraded version of the 5.6 cell, 200 MV/m peak field X-band gun designed at SLAC in 2003 for the Compton Scattering experiment run in ASTA. This new version includes some features implemented in 2006 on the LCLS gun such as racetrack couplers, increased mode separation and elliptical irises. These upgrades were developed in collaboration with LLNL since the same gun will be used in an injector formore » a LLNL Gamma-ray Source. Our beamline includes an X-band acceleration section which takes the electron beam up to 100 MeV and an electron beam measurement station. Other X-Band guns such as the UCLA Hybrid gun will be characterized at our facility.« less

Gun utopias? Firearm access and ownership in Israel and Switzerland.

PubMed

Rosenbaum, Janet E

2012-02-01

The 2011 attempted assassination of a US representative renewed the national gun control debate. Gun advocates claim mass-casualty events are mitigated and deterred with three policies: (a) permissive gun laws, (b) widespread gun ownership, (c) and encouragement of armed civilians who can intercept shooters. They cite Switzerland and Israel as exemplars. We evaluate these claims with analysis of International Crime Victimization Survey (ICVS) data and translation of laws and original source material. Swiss and Israeli laws limit firearm ownership and require permit renewal one to four times annually. ICVS analysis finds the United States has more firearms per capita and per household than either country. Switzerland and Israel curtail off-duty soldiers' firearm access to prevent firearm deaths. Suicide among soldiers decreased by 40 per cent after the Israeli army's 2006 reforms. Compared with the United States, Switzerland and Israel have lower gun ownership and stricter gun laws, and their policies discourage personal gun ownership.

Development of a high power electron beam welding gun with replaceable high voltage feed-through insulators

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

Saha, T.K; Mascarenhas, M.; Kandaswamy, E., E-mail: tanmay@barc.gov.in

Ceramic to metal sealed feed-through insulators are commonly used in electron beam welding gun. The above feed-through insulators are susceptible to failure, as the brazing joints in them are not always very strong. Failure in one of these feed-through could render the complete gun unusable. This problem has already been faced in BARC, which led to the development of the electron gun with replaceable feed through insulators. A 24 kW Electron Beam Welding (EBW) gun with indigenous designed replaceable insulators is fabricated in BARC. Emphasis during the design of the gun had been to reduce the use of imported componentsmore » to zero. This paper describes the design and fabrication of this gun and reports various simulations and tests performed. Beam trajectory of the gun is numerically computed and presented. Weld passes were carried out on stainless steel plates show satisfactory penetrations. (author)« less

Techniques for measuring ultrahigh-pressure Hugoniot equation of state on a three-stage gas gun

NASA Astrophysics Data System (ADS)

Wang, Xiang; Hu, Jianbo; Dai, Chengda; Wang, Qiangsong; Bo, Jingsong; Tan, Hua; Yu, Yuying

2011-06-01

A three-stage gas gun was developed by mounting an extending launcher tube on a two-stage gas gun, and was successfully applied to perform ultrahigh-pressure Hugoniot measurements for Ta and Pt by using this three-stage gun. Here we introduced the three-stag gas gun launcher and Hugoniot measurement techniques, including shock front shape diagnosis, shock wave velocity and impact velocity measurement as well as numerical simulation. By using this three-stage gun, Ta or Pt impactors were launched up to ~10 km/s, and the Hugoniot data were respectively measured with high accuracy up to 750 GPa for Ta and 1TPa for Pt. It is demonstrated that the three-stage gas gun is a promising technique for studying the ultrahigh-pressure properties of materials, which never before obtained by utilizing two-stage light-gas-gun.

Retinal Anatomy and Electrode Array Position in Retinitis Pigmentosa Patients after Argus II Implantation: an International Study.

PubMed

Gregori, Ninel Z; Callaway, Natalia F; Hoeppner, Catherine; Yuan, Alex; Rachitskaya, Aleksandra; Feuer, William; Ameri, Hossein; Arevalo, J Fernando; Augustin, Albert J; Birch, David G; Dagnelie, Gislin; Grisanti, Salvatore; Davis, Janet L; Hahn, Paul; Handa, James T; Ho, Allen C; Huang, Suber S; Humayun, Mark S; Iezzi, Raymond; Jayasundera, K Thiran; Kokame, Gregg T; Lam, Byron L; Lim, Jennifer I; Mandava, Naresh; Montezuma, Sandra R; Olmos de Koo, Lisa; Szurman, Peter; Vajzovic, Lejla; Wiedemann, Peter; Weiland, James; Yan, Jiong; Zacks, David N

2018-06-22

To assess the retinal anatomy and array position in the Argus II Retinal Prosthesis recipients. Prospective, non-comparative cohort study METHODS: Setting: international multicenter study PATIENTS: Argus II recipients enrolled in the Post-Market Surveillance Studies. Spectral-domain Optical Coherence Tomography images collected for the Surveillance Studies (NCT01860092 and NCT01490827) were reviewed. Baseline and postoperative macular thickness, electrode-retina distance (gap), optic disc-array overlap, and preretinal membrane presence were recorded at 1, 3, 6, and 12 months. Axial retinal thickness and axial gap along the array's long axis (a line between the tack and handle), maximal retinal thickness and maximal gap along a B-scan near the tack, midline, and handle. Thirty-three patients from 16 surgical sites in the United States and Germany were included. Mean axial retinal thickness increased from month 1 through month 12 at each location, but reached statistical significance only at the array midline (p-value=0.007). The rate of maximal thickness increase was highest near the array midline (slope=6.02, p=0.004), compared to the tack (slope=3.60, p<0.001) or the handle (slope=1.93, p=0.368). The mean axial and maximal gaps decreased over the study period, and the mean maximal gap size decrease was significant at midline (p=0.032). Optic disc-array overlap was seen in the minority of patients. Preretinal membranes were common before and after implantation. Progressive macular thickening under the array was common and corresponded to decreased electrode-retina gap over time. By month 12, the array was completely apposed to the macula in approximately half of the eyes. Copyright © 2018. Published by Elsevier Inc.

Unbalanced field RF electron gun

DOEpatents

Hofler, Alicia

2013-11-12

A design for an RF electron gun having a gun cavity utilizing an unbalanced electric field arrangement. Essentially, the electric field in the first (partial) cell has higher field strength than the electric field in the second (full) cell of the electron gun. The accompanying method discloses the use of the unbalanced field arrangement in the operation of an RF electron gun in order to accelerate an electron beam.

G6PD deficiency from lyonization after hematopoietic stem cell transplantation from female heterozygous donors.

PubMed

Au, W-Y; Pang, A; Lam, K K Y; Song, Y-Q; Lee, W-M; So, J C C; Kwong, Y-L

2007-10-01

To determine whether during hematopoietic stem cell transplantation (HSCT), X-chromosome inactivation (lyonization) of donor HSC might change after engraftment in recipients, the glucose-6-phosphate dehydrogenase (G6PD) gene of 180 female donors was genotyped by PCR/allele-specific primer extension, and MALDI-TOF mass spectrometry/Sequenom MassARRAY analysis. X-inactivation was determined by semiquantitative PCR for the HUMARA gene before/after HpaII digestion. X-inactivation was preserved in most cases post-HSCT, although altered skewing of lyonization might occur to either of the X-chromosomes. Among pre-HSCT clinicopathologic parameters analyzed, only recipient gender significantly affected skewing. Seven donors with normal G6PD biochemically but heterozygous for G6PD mutants were identified. Owing to lyonization changes, some donor-recipient pairs showed significantly different G6PD levels. In one donor-recipient pair, extreme lyonization affecting the wild-type G6PD allele occurred, causing biochemical G6PD deficiency in the recipient. In HSCT from asymptomatic female donors heterozygous for X-linked recessive disorders, altered lyonization might cause clinical diseases in the recipients.

Wotan’s Workshop: Military Experiments before World War II

DTIC Science & Technology

2013-06-27

photo: A column of mock tanks—with wood and canvas armor shapes mounted on light vehicles—participated in German military maneuvers in 1928. (Imperial...37mm antitank gun. The gunners called it a “ wood -o- meter” and claimed it could fire 400 splinters and 15 drops of turpentine per minute. Charles Gorry...ticipation in maneuvers. These surrogates, made of wood and canvas and mounted on cars or even on bicycles, were used in force-on-force maneuvers that

Soviet Naval Special Purpose Forces: Origins and Operations in World War II

DTIC Science & Technology

1989-12-01

amphibious aircraft onto a lake, from which they walked into the area between Nikel and Luostari and back out again. Their journey lasted ten days and...moved up into the snow-covered hills, and after some hours of movement, followed a tele- phone wire to a German guard post. Without carefully observing...telephone wire in rolls. They moved all the captured materiel to shore, and then to their base. The detachment now had enemy guns and ammunition for use

A-10 Thunderbolt II (Warthog) Systems Engineering Case Study

DTIC Science & Technology

2010-01-01

Visual Flight Rules (VFR) navigation aids. The “lean” package added Doppler Navigation for night and adverse weather, and a radar ranger and gun...and a big boost for the technology came in 1965 when the Air Force selected the TF39 engine to power the C-5 Galaxy heavy lift aircraft. Still, there...and Staff College, entitled to wear the Ranger Tab and has a real appreciation for the role of CAS in combat. Upon leaving active duty he served

Testing a GaAs cathode in SRF gun

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

Wang, E.; Kewisch, J.; Ben-Zvi, I.

RF electron guns with a strained superlattice GaAs cathode are expected to generate polarized electron beams of higher brightness and lower emittance than do DC guns, due to their higher field gradient at the cathode's surface and lower cathode temperature. We plan to install a bulk GaAs:Cs in a SRF gun to evaluate the performance of both the gun and the cathode in this environment. The status of this project is: In our 1.3 GHz 1/2 cell SRF gun, the vacuum can be maintained at nearly 10{sup -12} Torr because of cryo-pumping at 2K. With conventional activation of bulk GaAs,more » we obtained a QE of 10% at 532 nm, with lifetime of more than 3 days in the preparation chamber and have shown that it can survive in transport from the preparation chamber to the gun. The beam line has been assembled and we are exploring the best conditions for baking the cathode under vacuum. We report here the progress of our test of the GaAs cathode in the SRF gun. Future particle accelerators, such as eRHIC and the ILC require high-brightness, high-current polarized electrons. Strained superlattice GaAs:Cs has been shown to be an efficient cathode for producing polarized electrons. Activation of GaAs with Cs,O(F) lowers the electron affinity and makes it energetically possible for all the electrons, excited into the conduction band that drift or diffuse to the emission surface, to escape into the vacuum. Presently, all operating polarized electron sources, such as the CEBAF, are DC guns. In these devices, the excellent ultra-high vacuum extends the lifetime of the cathode. However, the low field gradient on the photocathode's emission surface of the DC guns limits the beam quality. The higher accelerating gradients, possible in the RF guns, generate a far better beam. Until recently, most RF guns operated at room temperature, limiting the vacuum to {approx}10{sup -9} Torr. This destroys the GaAs's NEA surface. The SRF guns combine the excellent vacuum conditions of DC guns and the high accelerating gradient of the RF guns, potentially offering a long lived cathode with very low emittance. Testing this concept requires preparation of the cathode, transportation to the SRF gun and evaluation of the performance of the cathode and the gun at cryogenic temperatures. In our work at BNL, we successfully activated the bulk GaAs in the preparation chamber. The highest quantum efficient was 10% at 532 nm that fell to 0.5% after 100 hours. We explored three different ways to activate the GaAs. We verified that the GaAs photocathode remains stable for 30 hours in a 10{sup -11} Torr vacuum. Passing the photocathode through the low 10{sup -9} Torr transfer section in several seconds caused the QE to drop to 0.8%. The photocathode with 0.8% QE can be tested for the SRF gun. The gun and beam pipe were prepared and assembled. After baking at 200 C baking, the vacuum of the gun and beam pipe can sustain a low 10{sup -11} Torr at room temperature. The final test to extract electrons from the gun is ongoing. In this paper, we discuss our progress with this SRF gun and the results of the photocathode in preparation chamber and in magnet transfer line.« less

Legal status and source of offenders' firearms in states with the least stringent criteria for gun ownership.

PubMed

Vittes, Katherine A; Vernick, Jon S; Webster, Daniel W

2013-02-01

Gun possession by high-risk individuals presents a serious threat to public safety. U.S. federal law establishes minimum criteria for legal purchase and possession of firearms; many states have laws disqualifying additional categories for illegal possession. We used data from a national survey of state prison inmates to calculate: 1) the proportion of offenders, incarcerated for crimes committed with firearms in 13 states with the least restrictive firearm purchase and possession laws, who would have been prohibited if their states had stricter gun laws; and 2) the source of gun acquisition for offenders who were and were not legally permitted to purchase and possess firearms. Nearly three of ten gun offenders (73 of 253 or 28.9%) were legal gun possessors but would have been prohibited from purchasing or possessing firearms when committing their most recent offense if their states had stricter prohibitions. Offenders who were already prohibited under current law acquired their gun from a licensed dealer, where a background check is required, five times less often than offenders who were not prohibited (3.9% vs. 19.9%; χ(2)=13.31; p≤0.001). Nearly all (96.1%) offenders who were legally prohibited, acquired their gun from a supplier not required to conduct a background check. Stricter gun ownership laws would have made firearm possession illegal for many state prison inmates who used a gun to commit a crime. Requiring all gun sales to be subject to a background check would make it more difficult for these offenders to obtain guns.

Gun Violence Following Inpatient Psychiatric Treatment: Offense Characteristics, Sources of Guns, and Number of Victims.

PubMed

Kivisto, Aaron J

2017-10-01

This study presents data on the relative contribution to gun violence by people with a history of inpatient psychiatric treatment and on federal efforts to deter presumptively dangerous persons from obtaining firearms, information useful for analyzing the potential public health benefits of gun policies targeting people with serious mental illness. The study also estimates the reduction in gun violence victims that would be expected if individuals with a previous psychiatric hospitalization were prohibited from purchasing firearms. Data from 838 violent gun offenders from a nationally representative sample of state prison inmates were analyzed. Those with and without a history of psychiatric hospitalization were compared on a range of offense characteristics, including relationship to the victim, number of victims, location of the offense, and source of firearms. Inmates with a history of hospitalization constituted 12% of all violent gun offenders and accounted for 13% of the sample's victims. They were less likely than those without a previous hospitalization to victimize strangers (odds ratio=.52) and were no more likely to commit gun violence in public or to have multiple victims. Among those with previous hospitalizations, 78% obtained guns from sources not subject to federal background checks. Of the total 1,041 victims of gun violence, only 3% were victimized by participants with a history of hospitalization who obtained guns from currently regulated sources. Prohibiting all individuals with a history of psychiatric hospitalization from purchasing firearms, absent expanded background checks, was estimated to reduce the number of gun violence victims by only 3%.

Gun carrying and conduct disorder: a highly combustible combination? Implications for juvenile justice and mental and public health.

PubMed

Loeber, Rolf; Burke, Jeffrey D; Mutchka, John; Lahey, Benjamin B

2004-02-01

To examine concealed gun carrying between the ages of 12 and 17 years in a population of clinic-referred boys, many of whom qualified for a disruptive behavior disorder, including conduct disorder (CD); to identify factors and diagnoses related to concealed gun carrying; and to examine the extent to which gun carrying is associated with crime in adulthood. Longitudinal follow-up study. Pittsburgh, Pa, and Athens and Atlanta, Ga. One hundred seventy-seven clinic-referred boys, first assessed between the ages of 7 and 12 years and followed up yearly until the age of 19 years. Violence, property offenses, and drug charges in adulthood. Between the ages of 12 and 17 years, 1 in 5 participants carried a concealed gun, and the annual prevalence increased linearly with age. More than half (61.1%) carried a gun for 1 year only. Gun carrying was significantly (incident rate ratio, 3.93%; 95% confidence interval, 1.60-9.60) associated with CD. Conduct disorder, maternal psychopathy, victimization, and parental monitoring increased the risk of gun carrying by a factor of 8. Adult crime was best predicted by gun carrying, CD, and parental monitoring. Gun carrying predicted drug charges, but not violence or property offenses. Even though the carrying of handguns by juveniles is prohibited, young men with symptoms of CD are more likely to carry guns than young men without CD. The findings are discussed in terms of the need for the inclusion of gun carrying among the symptoms of CD.

The advantages of the high voltage solar array for electric propulsion

NASA Technical Reports Server (NTRS)

Sater, B. L.

1973-01-01

The high voltage solar array (HVSA) offers improvements in efficiency, weight, and reliability for the electric propulsion power system. The basic HVSA technology involves designing the solar array to deliver power in the form required by the ion thruster. This paper delves into conventional power processes and problems associated with ion thruster operation using SERT II experience for examples. In this light, the advantages of the HVSA concept for electric propulsion are presented. Tests conducted operating the SERT II thruster system in conjunction with HVSA are discussed. Thruster operation was observed to be normal and in some respects improved.

Hand injury with a nail gun: a case report with literature review.

PubMed

Boya, Hakan; Uzun, Belkan

2015-01-01

The nail gun was introduced in the late 1950s to increase the ease of driving nails, studs, bolts, or staples into various hard surfaces. The nail gun is a potentially dangerous device that is still commonly used in the construction industry. Since its introduction, an increasing number of studies have reported injuries associated with nail guns. Nail gun-related injuries-such as to the head, neck, and chest-can be devastating, and in some cases, even fatal. Extremity injuries, notably in the hand, can cause loss of function, missed work, and long-term health effects. This case report describes a nail-gun injury of the hand along with a discussion of the unique features of and treatment strategies for nail gun injuries.

Impact Testing for Materials Science at NASA - MSFC

NASA Technical Reports Server (NTRS)

Sikapizye, Mitch

2010-01-01

The Impact Testing Facility (ITF) at NASA - Marshall Space Flight Center is host to different types of guns used to study the effects of high velocity impacts. The testing facility has been and continues to be utilized for all NASA missions where impact testing is essential. The Facility has also performed tests for the Department of Defense, other corporations, as well as universities across the nation. Current capabilities provided by Marshall include ballistic guns, light gas guns, exploding wire gun, and the Hydrometeor Impact Gun. A new plasma gun has also been developed which would be able to propel particles at velocities of 20km/s. This report includes some of the guns used for impact testing at NASA Marshall and their capabilities.

Spatio-temporal patterns of gun violence in Syracuse, New York 2009-2015.

PubMed

Larsen, David A; Lane, Sandra; Jennings-Bey, Timothy; Haygood-El, Arnett; Brundage, Kim; Rubinstein, Robert A

2017-01-01

Gun violence in the United States of America is a large public health problem that disproportionately affects urban areas. The epidemiology of gun violence reflects various aspects of an infectious disease including spatial and temporal clustering. We examined the spatial and temporal trends of gun violence in Syracuse, New York, a city of 145,000. We used a spatial scan statistic to reveal spatio-temporal clusters of gunshots investigated and corroborated by Syracuse City Police Department for the years 2009-2015. We also examined predictors of areas with increased gun violence using a multi-level zero-inflated Poisson regression with data from the 2010 census. Two space-time clusters of gun violence were revealed in the city. Higher rates of segregation, poverty and the summer months were all associated with increased risk of gun violence. Previous gunshots in the area were associated with a 26.8% increase in the risk of gun violence. Gun violence in Syracuse, NY is both spatially and temporally stable, with some neighborhoods of the city greatly afflicted.

Spatio-temporal patterns of gun violence in Syracuse, New York 2009-2015

PubMed Central

Lane, Sandra; Jennings-Bey, Timothy; Haygood-El, Arnett; Brundage, Kim; Rubinstein, Robert A.

2017-01-01

Gun violence in the United States of America is a large public health problem that disproportionately affects urban areas. The epidemiology of gun violence reflects various aspects of an infectious disease including spatial and temporal clustering. We examined the spatial and temporal trends of gun violence in Syracuse, New York, a city of 145,000. We used a spatial scan statistic to reveal spatio-temporal clusters of gunshots investigated and corroborated by Syracuse City Police Department for the years 2009–2015. We also examined predictors of areas with increased gun violence using a multi-level zero-inflated Poisson regression with data from the 2010 census. Two space-time clusters of gun violence were revealed in the city. Higher rates of segregation, poverty and the summer months were all associated with increased risk of gun violence. Previous gunshots in the area were associated with a 26.8% increase in the risk of gun violence. Gun violence in Syracuse, NY is both spatially and temporally stable, with some neighborhoods of the city greatly afflicted. PMID:28319125

Specifying the role of exposure to violence and violent behavior on initiation of gun carrying: a longitudinal test of three models of youth gun carrying.

PubMed

Spano, Richard; Pridemore, William Alex; Bolland, John

2012-01-01

Two waves of longitudinal data from 1,049 African American youth living in extreme poverty are used to examine the impact of exposure to violence (Time 1) and violent behavior (Time 1) on first time gun carrying (Time 2). Multivariate logistic regression results indicate that (a) violent behavior (Time 1) increased the likelihood of initiation of gun carrying (Time 2) by 76% after controlling for exposure to violence at Time 1, which is consistent with the stepping stone model of youth gun carrying, and (b) youth who were both exposed to violence at Time 1 and engaged in violent behavior at Time 1 were more than 2.5 times more likely to initiate gun carrying at Time 2 compared to youth who had neither of these characteristics, which supports the cumulative risk model of youth gun carrying. The authors discuss the implications of these findings in clarifying the role of violence in the community on youth gun carrying and the primary prevention of youth gun violence.

Magnetic Reconnection Results on the Swarthmore Spheromak Experiment

NASA Astrophysics Data System (ADS)

Kornack, T. W.; Sollins, P. K.; Brown, M. R.

1997-11-01

Linear and 2D arrays of magnetic probes are used to study magnetic reconnection in the Swarthmore Spheromak Experiment (SSX). Opposing coaxial plasma guns form two identical spheromaks into adjacent 0.5 m diameter copper flux conservers. The flux conservers have symmetrical openings that allow the spheromaks to merge in a controlled manner. The stable equilibrium of the spheromaks provides a reservoir of magnetic flux for reconnection experiments. Currently, the magnetic configuration of the spheromaks allows the study of counter-helicity reconnection. Preliminary analysis will be presented and may include 2D B field movies of the reconnection region, measurement of the reconnection rate and comparison to the Sweet-Parker and standard Petschek models.

Observing Solar Radio Bursts from the Lunar Surface

NASA Technical Reports Server (NTRS)

MacDowall, R. J.; Lazio, T. J.; Bale, S. D.; Burns, J.; Gopalswamy, N.; Jones, D. L.; Kaiser, M. L.; Kasper, J.; Weiler, K. W.

2010-01-01

Locating low frequency radio observatories on the lunar surface has a number of advantages. Here, we describe the Radio Observatory for Lunar Sortie Science (ROLSS), a concept for a low frequency, radio imaging interferometric array designed to study particle acceleration in the corona and inner heliosphere. ROLSS would be deployed during an early lunar sortie or by a robotic rover as part of an unmanned landing. The prime science mission is to image type II and type III solar radio bursts with the aim of determining the sites at and mechanisms by which the radiating particles are accelerated. Secondary science goals include constraining the density of the lunar ionosphere by searching for a low radio frequency cutoff of the solar radio emissions and constraining the low energy electron population in astrophysical sources. Furthermore, ROLSS serves a pathfinder function for larger lunar radio arrays. Key design requirements on ROLES include the operational frequency and angular resolution. The electron densities in the solar corona and inner heliosphere are such that the relevant emission occurs below 10 MHz, essentially unobservable from Earth's surface due to the terrestrial ionospheric cutoff. Resolving the potential sites of particle acceleration requires an instrument with an angular resolution of at least 2 deg, equivalent to a linear array size of approximately 500 meters. Operations would consist of data acquisition during the lunar day, with regular data downlinks. The major components of the ROLSS array are 3 antenna arms arranged in a Y shape, with a central electronics package (CEP). Each antenna arm is a linear strip of polyimide film (e.g., Kapton (TM)) on which 16 single polarization dipole antennas are located by depositing a conductor (e.g., silver). The arms also contain transmission lines for carrying the radio signals from the science antennas to the CEP.

Transport in arrays of submicron Josephson junctions over a ground plane

NASA Astrophysics Data System (ADS)

Ho, Teressa Rae

One-dimensional (1D) and two-dimensional (2D) arrays of Al islands linked by submicron Al/Alsb{x}Osb{y}/Al tunnel junctions were fabricated on an insulating layer grown on a ground plane. The arrays were cooled to temperatures as low as 20 mK where the Josephson coupling energy Esb{J} of each junction and the charging energy Esb{C} of each island were much greater than the thermal energy ksb{B}T. The capacitance Csb{g} between each island and the ground plane was much greater than the junction capacitance C. Two classes of arrays were studied. In the first class, the normal state tunneling resistance of the junctions was much larger than the resistance quantum for single electrons, Rsb{N}≫ Rsb{Qe}equiv h/esp2≈ 25.8 kOmega, and the islands were driven normal by an applied magnetic field such that Esb{J}=0 and the array was in the Coulomb blockade regime. The arrays were made on degenerately-doped Si, thermally oxidized to a thickness of approximately 100 nm. The current-voltage (I-V) characteristics of a 1D and a 2D array were measured and found to display a threshold voltage Vsb{T} below which little current flows. Above threshold the array current I scaled as (V/Vsb{T}-1)sp{zeta}; this scaling behavior was interpreted as a dynamic critical phenomenon. A 2D array with intentionally-added island area disorder was also measured and found to have a similar threshold voltage Vsb{T} but a larger scaling exponent zeta than the array with only intrinsic disorder. In the second class of arrays, the normal state tunneling resistance of the junctions was close to the resistance quantum for Cooper pairs, Rsb{N}≈ Rsb{Q}equiv h/4esp2≈ 6.45kOmega, such that Esb{J}/Esb{C}≈1. The arrays were made on GaAs/Alsb{0.3}Gasb{0.7}As heterostructures with a two-dimensional electron gas (2DEG) approximately 100 nm below the surface. The resistance per square of the 2DEG, Rsb{g}, could be varied by applying a large voltage between the 2DEG and a metallic back gate; varying Rsb{g} varied the dissipation associated with the local electrodynamic environment. For a 2D array, the I-V characteristics made a transition from superconductor-like to insulator-like as the resistance of the ground plane Rsb{g} was increased. The zero-bias resistance Rsb0 of the array increased exponentially with Rsb{g}. A small magnetic field was applied perpendicularly to the array, and the I-V characteristics of the array changed from superconductor-like to insulator-like as the magnetic field (measured in units of frustration f, the number of flux quanta per unit cell) was increased. Increasing Rsb{g} drove the magnetic field-driven superconductor-like to insulator-like transition of the I-V characteristics to lower values of f, and increasing f drove the dissipation-driven transition to lower values of Rsb{g}. Three 1D arrays were also measured. One array displayed superconducting behavior at low temperature, and the size of the supercurrent increased, reached a maximum, and then decreased, as Rsb{g} was increased. Two arrays displayed insulating behavior at low temperature, and the size of the Coulomb gap increased with increasing Rsb{g}. The zero-bias resistance of the array Rsb0 increased faster than exponentially with Rsb{g}.

77 FR 32986 - Notice of Inventory Completion: The University of Alabama Museums, Tuscaloosa, AL

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-04

... than 2,032 glass beads, 1 lot of more than 17 shell beads, 1 unidentified bead, 1 gun lock, 1 gun butt plate, 1 gun stock, 2 gun barrels, 1 brass ramrod support, 8 musket balls, 2 iron buckles, 1 iron handle... fragments, 1 unidentified bead, 2 glass beads, 1 gun flint, 1 iron knife blade, 1 iron nail, 1 musket ball...

The Southern H ii Region Discovery Survey (SHRDS): Pilot Survey

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

Brown, C.; Dickey, John M.; Jordan, C.

The Southern H ii Region Discovery Survey is a survey of the third and fourth quadrants of the Galactic plane that will detect radio recombination line (RRL) and continuum emission at cm-wavelengths from several hundred H ii region candidates using the Australia Telescope Compact Array. The targets for this survey come from the WISE Catalog of Galactic H ii Regions and were identified based on mid-infrared and radio continuum emission. In this pilot project, two different configurations of the Compact Array Broad Band receiver and spectrometer system were used for short test observations. The pilot surveys detected RRL emission frommore » 36 of 53 H ii region candidates, as well as seven known H ii regions that were included for calibration. These 36 recombination line detections confirm that the candidates are true H ii regions and allow us to estimate their distances.« less

The Transmission of Gun and Other Weapon-Involved Violence Within Social Networks

PubMed Central

Tracy, Melissa; Braga, Anthony A.; Papachristos, Andrew V.

2016-01-01

Fatal and nonfatal injuries resulting from gun violence remain a persistent problem in the United States. The available research suggests that gun violence diffuses among people and across places through social relationships. Understanding the relationship between gun violence within social networks and individual gun violence risk is critical in preventing the spread of gun violence within populations. This systematic review examines the existing scientific evidence on the transmission of gun and other weapon-related violence in household, intimate partner, peer, and co-offending networks. Our review identified 16 studies published between 1996 and 2015 that suggest that exposure to a victim or perpetrator of violence in one's interpersonal relationships and social networks increases the risk of individual victimization and perpetration. Formal network analyses find high concentrations of gun violence in small networks and that exposure to gun violence in one's networks is highly correlated with one's own probability of being a gunshot victim. Physical violence by parents and weapon use by intimate partners also increase risk for victimization and perpetration. Additional work is needed to better characterize the mechanisms through which network exposures increase individual risk for violence and to evaluate interventions aimed at disrupting the spread of gun and other weapon violence in high-risk social networks. PMID:26733492

Hypervelocity Impact Testing of Space Station Freedom Solar Cells

NASA Technical Reports Server (NTRS)

Christie, Robert J.; Best, Steve R.; Myhre, Craig A.

1994-01-01

Solar array coupons designed for the Space Station Freedom electrical power system were subjected to hypervelocity impacts using the HYPER facility in the Space Power Institute at Auburn University and the Meteoroid/Orbital Debris Simulation Facility in the Materials and Processes Laboratory at the NASA Marshall Space Flight Center. At Auburn, the solar cells and array blanket materials received several hundred impacts from particles in the micron to 100 micron range with velocities typically ranging from 4.5 to 10.5 km/s. This fluence of particles greatly exceeds what the actual components will experience in low earth orbit. These impacts damaged less than one percent of total area of the solar cells and most of the damage was limited to the cover glass. There was no measurable loss of electrical performance. Impacts on the array blanket materials produced even less damage and the blanket materials proved to be an effective shield for the back surface of the solar cells. Using the light gas gun at MSFC, one cell of a four cell coupon was impacted by a 1/4 inch spherical aluminum projectile with a velocity of about 7 km/s. The impact created a neat hole about 3/8 inch in diameter. The cell and coupon were still functional after impact.

Structural and optical properties of glancing angle deposited In2O3 columnar arrays and Si/In2O3 photodetector

NASA Astrophysics Data System (ADS)

Mondal, A.; Shougaijam, B.; Goswami, T.; Dhar, J. C.; Singh, N. K.; Choudhury, S.; Chattopadhay, K. K.

2014-04-01

Ordered and perpendicular columnar arrays of In2O3 were synthesized on conducting ITO electrode by a simple glancing angle deposition (GLAD) technique. The as-deposited In2O3 columns were investigated by field emission gun-scanning electron microscope (FEG-SEM). The average length and diameter of the columns were estimated ˜400 nm and ˜100 nm, respectively. The morphology of the structure was examined by transmission electron microscopy (TEM). X-ray diffraction (XRD) analysis shows the polycrystalline nature of the sample which was verified by selective area electron diffraction (SAED) analysis. The growth mechanism and optical properties of the columns were also discussed. Optical absorption shows that In2O3 columns have a high band to band transition at ˜3.75 eV. The ultraviolet and green emissions were obtained from the In2O3 columnar arrays. The P-N junction was formed between In2O3 and P-type Si substrate. The GLAD synthesized In2O3 film exhibits low current conduction compared to In2O3 TF. However, the Si/GLAD-In2O3 detector shows ˜1.5 times enhanced photoresponsivity than that of Si/In2O3 TF.

Controllable synthesis of mesoporous Co{sub 3}O{sub 4} nanoflake array and its application for supercapacitor

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

Xiao, Anguo, E-mail: hixiaoanguo@126.com; Zhou, Shibiao; Zuo, Chenggang

Graphical abstract: Electrodeposited mesoporous Co{sub 3}O{sub 4} nanoflake arrays exhibit porous structure composed of mesoporous nanoflakes and high supercapacitor performance. - Highlights: • Mesoporous Co{sub 3}O{sub 4} nanoflake arrays are prepared via electrodeposition method. • Mesoporous nanowall arrays are favorable for fast ion/electron transfer. • Mesoporous Co{sub 3}O{sub 4} nanoflake arrays show excellent supercapacitor performance. - Abstract: A mesoporous Co{sub 3}O{sub 4} nanoflake array grown on carbon cloth is prepared by a facile electrodeposition method with a following annealing process. The as-prepared Co{sub 3}O{sub 4} nanoflake possesses a continuous mesopores ranging from 2 to 5 nm and grows tightly onmore » the substrate forming a porous net-like structure with macropores of 20–200 nm. The electrochemical performance of the mesoporous Co{sub 3}O{sub 4} nanoflake arrays as pseudocapcitor electrode are investigated by cyclic voltammograms and galvanostatic charge/discharge tests in 2 M KOH. The as-prepared Co{sub 3}O{sub 4} array exhibits a high discharge capacitance and excellent rate capability with 450 F g{sup −1}, 436 F g{sup −1}, 408 F g{sup −1}, 380 F g{sup −1}and 363 F g{sup −1} at 1, 2, 4, 10, and 20 A g{sup −1}, respectively. The specific capacitance of 81% is maintained from 1 A g{sup −1} to 20 A g{sup −1}. The electrode also shows rather good cycling stability and exhibits a specific capacitance of 414 F g{sup −1} after 5000 cycles.« less

Optimizing Cu(II) removal from aqueous solution by magnetic nanoparticles immobilized on activated carbon using Taguchi method.

PubMed

Ebrahimi Zarandi, Mohammad Javad; Sohrabi, Mahmoud Reza; Khosravi, Morteza; Mansouriieh, Nafiseh; Davallo, Mehran; Khosravan, Azita

2016-01-01

This study synthesized magnetic nanoparticles (Fe(3)O(4)) immobilized on activated carbon (AC) and used them as an effective adsorbent for Cu(II) removal from aqueous solution. The effect of three parameters, including the concentration of Cu(II), dosage of Fe(3)O(4)/AC magnetic nanocomposite and pH on the removal of Cu(II) using Fe(3)O(4)/AC nanocomposite were studied. In order to examine and describe the optimum condition for each of the mentioned parameters, Taguchi's optimization method was used in a batch system and L9 orthogonal array was used for the experimental design. The removal percentage (R%) of Cu(II) and uptake capacity (q) were transformed into an accurate signal-to-noise ratio (S/N) for a 'larger-the-better' response. Taguchi results, which were analyzed based on choosing the best run by examining the S/N, were statistically tested using analysis of variance; the tests showed that all the parameters' main effects were significant within a 95% confidence level. The best conditions for removal of Cu(II) were determined at pH of 7, nanocomposite dosage of 0.1 gL(-1) and initial Cu(II) concentration of 20 mg L(-1) at constant temperature of 25 °C. Generally, the results showed that the simple Taguchi's method is suitable to optimize the Cu(II) removal experiments.

Standardized UXO Technology Demonstration Site Blind Grid Scoring Record No. 806 (U.S. Geological Survey, TMGS Magnetometer/Towed Array)

DTIC Science & Technology

2007-05-01

BOX 25046, FEDERAL CENTER, M.S. 964 DENVER, CO 80225-0046 TECHNOLOGY TYPE/PLATFORM: TMGS MAGNETOMETER/TOWED ARRAY PREPARED BY: U.S. ARMY...GEOLOGICAL SURVEY, TMGS MAGNETOMETER/TOWED ARRAY) 8-CO-160-UXO-021 Karwatka, Michael... TMGS Magnetometer/Towed Array, MEC Unclassified Unclassified Unclassified SAR (Page ii Blank) i ACKNOWLEDGMENTS

U.S. Army Biomedical Research and Development Laboratory Bibliography FY91-FY80 (Reverse Order). Appendix

DTIC Science & Technology

1991-01-01

G.E. Toms. 1991. SOF sterilizer, 1st article test. Memorandum Report No. 1 -91. Hodge, J.W., and G.E. Toms. 1991. Sterilizer, surgical instruments and...for the performance of FETAX, Stillwater, OK: Oklahoma State University Press. 3 Burrows, E.P. 1991. Mass spectral fragmentation pathways of 1 ...potential of LP1846 liquid gun propellant to induce unscheduled DNA synthesis in the in vitro hepatocyte DNA repair assay. Final report, Project Order

VIEW OF SOUTH GUN EMPLACEMENT. NOTE THE EXCAVATED EDGE OF ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW OF SOUTH GUN EMPLACEMENT. NOTE THE EXCAVATED EDGE OF THE GUN BLOCK IN THE FOREGROUND. VIEW FACING NORTH - U.S. Naval Base, Pearl Harbor, Ford Island 5-Inch Antiaircraft Battery, South Gun Emplacement, Ford Island, Pearl City, Honolulu County, HI

Children, Youth, and Gun Violence.

ERIC Educational Resources Information Center

Behrman, Richard E., Ed.

2002-01-01

This collection of articles summarizes knowledge and research about how gun violence affects children and youth and discusses which policies hold promise for reducing youth gun violence. The papers are: (1) "Statement of Purpose" (Richard E. Behrman); "Children, Youth, and Gun Violence: Analysis and Recommendations" (Kathleen…

Binding of the cSH3 Domain of Grb2 Adaptor to Two Distinct RXXK Motifs within Gab1 Docker Employs Differential Mechanisms

PubMed Central

McDonald, Caleb B.; Seldeen, Kenneth L.; Deegan, Brian J.; Bhat, Vikas; Farooq, Amjad

2010-01-01

A ubiquitous component of cellular signaling machinery, Gab1 docker plays a pivotal role in routing extracellular information in the form of growth factors and cytokines to downstream targets such as transcription factors within the nucleus. Here, using isothermal titration calorimetry (ITC) in combination with macromolecular modeling (MM), we show that although Gab1 contains four distinct RXXK motifs, designated G1, G2, G3 and G4, only G1 and G2 motifs bind to the cSH3 domain of Grb2 adaptor and do so with distinct mechanisms. Thus, while the G1 motif strictly requires the PPRPPKP consensus sequence for high-affinity binding to the cSH3 domain, the G2 motif displays preference for the PXVXRXLKPXR consensus. Such sequential differences in the binding of G1 and G2 motifs arise from their ability to adopt distinct polyproline type II (PPII)- and 310-helical conformations upon binding to the cSH3 domain, respectively. Collectively, our study provides detailed biophysical insights into a key protein-protein interaction involved in a diverse array of signaling cascades central to health and disease. PMID:21472810

Construction and characterization of the fringe field monochromator for a field emission gun

PubMed

Mook; Kruit

2000-04-01

Although some microscopes have shown stabilities sufficient to attain below 0.1 eV spectral resolution in high-resolution electron energy loss spectroscopy, the intrinsic energy width of the high brightness source (0.3-0.6 eV) has been limiting the resolution. To lower the energy width of the source to 50 meV without unnecessary loss of brightness, a monochromator has been designed consisting of a short (4 mm) fringe field Wien filter and a 150 nm energy selection slit (nanoslit) both to be incorporated in the gun area of the microscope. A prototype has been built and tested in an ultra-high-vacuum setup (10(-9) mbar). The monochromator, operating on a Schottky field emission gun, showed stable and reproducible operation. The nanoslits did not contaminate and the structure remained stable. By measuring the current through the slit structure a direct image of the beam in the monochromator could be attained and the monochromator could be aligned without the use of a microscope. Good dispersed imaging conditions were found indicating an ultimate resolution of 55 meV. A Mark II fringe field monochromator (FFM) was designed and constructed compatible with the cold tungsten field emitter of the VG scanning transmission microscope. The monochromator was incorporated in the gun area of the microscope at IBM T.J. Watson research center, New York. The monochromator was aligned on 100 kV and the energy distribution measured using the monochromator displayed a below 50 meV filtering capability. The retarding Wien filter spectrometer was used to show a 61 meV EELS system resolution. The FFM is shown to be a monochromator which can be aligned without the use of the electron microscope. This makes it directly applicable for scanning transmission microscopy and low-voltage scanning electron microscopy, where it can lower the resolution loss which is caused by chromatic blur of the spot.

Low Emittance Guns for the ILC Polarized Electron Beam

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

Clendenin, J. E.; Brachmann, A.; Ioakeimidi, K.

Polarized electron beams generated by DC guns are routinely available at several accelerators including JLAB, Mainz and SLAC. These guns operate with a cathode bias on the order of -100 kV. To minimize space charge effects, relatively long bunches are generated at the gun and then compressed longitudinally external to the gun just before and during initial acceleration. For linear colliders, this compression is accomplished using a combination of rf bunchers. For the basic design of the International Linear Collider (ILC), a 120 kV DC photocathode gun is used to produce a series of nanosecond bunches that are each compressedmore » by two sub-harmonic bunchers (SHBs) followed by an L-band buncher and capture section. The longitudinal bunching process results in a significantly higher emittance than produced by the gun alone. While high-energy experiments using polarized beams are not generally sensitive to the source emittance, there are several benefits to a lower source emittance including a simpler more efficient injector system and a lower radiation load during transport especially at bends as at the damping ring. For the ILC, the SHBs could be eliminated if the voltage of the gun is raised sufficiently. Simulations using the General Particle Tracer (GPT) package indicate that a cathode bias voltage of {>=}200 kV should allow both SHBs to be operated at 433 or even 650 MHz, while {>=}500 kV would be required to eliminate the SHBs altogether. Simulations can be used to determine the minimum emittance possible if the injector is designed for a given increased voltage. A possible alternative to the DC gun is an rf gun. Emittance compensation, routinely used with rf guns, is discussed for higher-voltage DC guns.« less

Low Emittance Guns for the ILC Polarized Electron Beam

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

Clendenin, J.E.; Brachmann, A.; Ioakeimidi, K.

Polarized electron beams generated by DC guns are routinely available at several accelerators including JLAB, Mainz and SLAC. These guns operate with a cathode bias on the order of -100 kV. To minimize space charge effects, relatively long bunches are generated at the gun and then compressed longitudinally external to the gun just before and during initial acceleration. For linear colliders, this compression is accomplished using a combination of rf bunchers. For the basic design of the International Linear Collider (ILC), a 120 kV DC photocathode gun is used to produce a series of nanosecond bunches that are each compressedmore » by two sub-harmonic bunchers (SHBs) followed by an L-band buncher and capture section. The longitudinal bunching process results in a significantly higher emittance than produced by the gun alone. While high-energy experiments using polarized beams are not generally sensitive to the source emittance, there are several benefits to a lower source emittance including a simpler more efficient injector system and a lower radiation load during transport especially at bends as at the damping ring. For the ILC, the SHBs could be eliminated if the voltage of the gun is raised sufficiently. Simulations using the General Particle Tracer (GPT) package indicate that a cathode bias voltage of {ge}200 kV should allow both SHBs to be operated at 433 or even 650 MHz, while {ge}500 kV would be required to eliminate the SHBs altogether. Simulations can be used to determine the minimum emittance possible if the injector is designed for a given increased voltage. A possible alternative to the DC gun is an rf gun. Emittance compensation, routinely used with rf guns, is discussed for higher-voltage DC guns.« less

Ultra-Wideband Array in PCB for Millimeter-Wave 5G and ISM

NASA Technical Reports Server (NTRS)

Novak, Markus H.; Volakis, John L.; Miranda, Felix A.

2017-01-01

Next generation 5G mobile architectures will take advantage of the millimeter-wave spectrum to deliver unprecedented bandwidth. Concurrently, there is a need to consolidate numerous disparate allocations into a single, multi-functional array. Existing arrays are either narrow-band, prohibitively expensive or cannot be scaled to these frequencies. In this paper, we present the first ultra-wideband millimeter-wave array to operate across the six 5G and ISM bands spanning 24-71 GHz. Critically, the array is realized using low-cost PCB. The design concept and optimized layout are presented, and fabrication and measurement considerations are discussed.

46th Annual Gun and Missile Systems Conference and Exhibition. Volume 3 - Thursday

DTIC Science & Technology

2011-09-01

Grade Sensors Through Use of Accelerated Aging Principles Mr. Scott Gift 11657 Modeling of the Autofrettage Processes of a Gun Barrel Mr. Sudhir...Emissions Measured on the Outer Portion of a Composite Barrel Ms. Rushie Ghimire GUN & MISSILE SYSTEMS ADDITIONAL AUTHORS GUN & MISSILE SYSTEMS...Transportation – Loading – Gun Fire to Barrel Exit – After Barrel Exit • Passing: Fuze safety devices remain safe; safe for disposal or safe for

Are "goods for guns" good for the community? An update of a community gun buyback program.

PubMed

Green, Jonathan; Damle, Rachelle N; Kasper, Rebecca E; Violano, Pina; Manno, Mariann; Nazarey, Pradeep P; Aidlen, Jeremy T; Hirsh, Michael P

2017-08-01

Gun violence remains a leading cause of death in the United States. Community gun buyback programs provide an opportunity to dispose of extraneous firearms. The purpose of this study was to understand the demographics, motivation, child access to firearms, and household mental illness of buyback participants in hopes of improving the program's effectiveness. A 2015 Injury Free Coalition for Kids gun buyback program which collaborated with local police departments was studied. We administered a 23-item questionnaire survey to gun buyback participants assessing demographic characteristics, motivation for relinquishing firearms, child firearm accessibility, and mental illness/domestic violence history. A total of 186 individuals from Central/Western Massachusetts turned in 339 weapons. Participants received between US $25 and US $75 in gift cards dependent on what type of gun was turned in, with an average cost of $41/gun. A total of 109 (59%) participants completed the survey. Respondents were mostly white (99%), men (90%) and first-time participants in the program (85.2%). Among survey respondents, 54% turned in firearms "for safety reasons." Respondents reported no longer needing/wanting their weapons (47%) and approximately one in eight participants were concerned the firearm(s) were accessible to children. Most respondents (87%) felt the program encouraged neighborhood awareness of firearm safety. Three of every five participants reported that guns still remained in their homes; additionally, 21% where children could potentially access them and 14% with a history of mental illness/suicide/domestic violence in the home. Gun buybacks can provide a low-cost means of removing unwanted firearms from the community. Most participants felt their homes were safer after turning in the firearm(s). In homes still possessing guns, emphasis on secure gun storage should continue, increasing the safety of children and families. The results of this survey also provided new insights into the association between mental illness/suicide and gun ownership. Epidemiological, level III.

First detection of thermal radio emission from solar-type stars with the Karl G. Jansky very large array

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

Villadsen, Jackie; Hallinan, Gregg; Bourke, Stephen

2014-06-20

We present the first detections of thermal radio emission from the atmospheres of solar-type stars τ Cet, η Cas A, and 40 Eri A. These stars all resemble the Sun in age and level of magnetic activity, as indicated by X-ray luminosity and chromospheric emission in Ca II H and K lines. We observed these stars with the Karl G. Jansky Very Large Array with sensitivities of a few μJy at combinations of 10.0, 15.0, and 34.5 GHz. τ Cet, η Cas A, and 40 Eri A are all detected at 34.5 GHz with signal-to-noise ratios of 6.5, 5.2, andmore » 4.5, respectively. 15.0 GHz upper limits imply a rising spectral index greater than 1.0 for τ Cet and 1.6 for η Cas A, at the 95% confidence level. The measured 34.5 GHz flux densities correspond to stellar disk-averaged brightness temperatures of roughly 10,000 K, similar to the solar brightness temperature at the same frequency. We explain this emission as optically thick thermal free-free emission from the chromosphere, with possible contributions from coronal gyroresonance emission above active regions and coronal free-free emission. These and similar quality data on other nearby solar-type stars, when combined with Atacama Large Millimeter/Submillimeter Array observations, will enable the construction of temperature profiles of their chromospheres and lower transition regions.« less

"Is there a gun in the home?" Assessing the risks of gun ownership in older adults.

PubMed

Pinholt, Ellen M; Mitchell, Joshua D; Butler, Jane H; Kumar, Harjinder

2014-06-01

An important ethical and safety concern that geriatricians, primary care providers, and home health professionals need to address is gun ownership by elderly adults. Those aged 65 and older now have the highest rate of gun ownership in America, and they also have a high prevalence of depression and suicide. Dementia can add additional layers of risk. Even older gun owners who are otherwise intellectually intact may benefit from information about gun safety with the increasing numbers of children being cared for by grandparents. Health professionals should ask patients, "Is there a gun in the home?" in the clinic and during home visits. Healthcare professionals must have knowledge and skills to address safe gun ownership in elderly adults. The 5 L's (Locked, Loaded, Little children, feeling Low, Learned owner) will assist professionals in addressing all aspects of safe ownership. © 2014, Copyright the Authors Journal compilation © 2014, The American Geriatrics Society.

Development program on a cold cathode electron gun

NASA Technical Reports Server (NTRS)

Spindt, C. A.

1979-01-01

A prototype electron gun with a field emitter cathode capable of producing 95 mA in a 1/4 mm diameter beam at 12 kV was produced. Achievement of this goal required supporting studies in cathode fabrication, cathode performance, gun design, cathode mounting and gun fabrication. A series of empirical investigations advanced fabrication technology: More stable emitters were produced and multiple cone failure caused by chain reaction discharges were reduced. The cathode is capable of producing well over 95 mA, but a substantial collector development effort was required to demonstrate emission levels in the 100 mA region. Space charge problems made these levels difficult to achieve. Recommendations are made for future process and materials investigation. Electron gun designs were modeled and tested. A pair of two-electrode gun structures were fabricated and tested; one gun was delivered to NASA. Cathodes were pretested up to 100 mA at SRI and delivered to NASA for test in the gun structure.

Gun Violence and Victimization of Strangers by Persons With a Mental Illness: Data From the MacArthur Violence Risk Assessment Study.

PubMed

Steadman, Henry J; Monahan, John; Pinals, Debra A; Vesselinov, Roumen; Robbins, Pamela Clark

2015-11-01

Highly publicized incidents in which people with apparent mental illnesses use guns to victimize strangers have important implications for public views of people with mental illnesses and the formation of mental health and gun policy. The study aimed to provide more data about this topic. MacArthur Violence Risk Assessment Study data were analyzed to determine the prevalence of violence by 951 patients after discharge from a psychiatric hospital, including gun violence, violence toward strangers, and gun violence toward strangers. Two percent of patients committed a violent act involving a gun, 6% committed a violent act involving a stranger, and 1% committed a violent act involving both a gun and a stranger. When public perceptions and policies regarding mental illness are shaped by highly publicized but infrequent instances of gun violence toward strangers, they are unlikely to help people with mental illnesses or to improve public safety.

A Proposed Direction Finding and Polarization Sensing Scheme.

DTIC Science & Technology

1976-03-01

on ’:i J -v nor any ’.o tion 4-u rn s e c, c. in a ,y x ay su-.plie soi a. cdl nir ino g cvsci f icati o-c, in ar"r’. mnner C o the >o d r c ,,,o-,r...SUPPLEMENTARY NOTES 19. KEY WORDS (Continue on reverse aide iI necessary and identify by block number) Direction-findingi t Polarization-sensing Small...antenna array 20. ABS CT (Continue on reverse aide If necesaery and identify by block number) This report proposes and demonstrates a direction finding

Acute Alcohol Consumption, Alcohol Outlets, and Gun Suicide

PubMed Central

Branas, Charles C.; Richmond, Therese S.; Ten Have, Thomas R.; Wiebe, Douglas J.

2014-01-01

A case–control study of 149 intentionally self-inflicted gun injury cases (including completed gun suicides) and 302 population-based controls was conducted from 2003 to 2006 in a major US city. Two focal independent variables, acute alcohol consumption and alcohol outlet availability, were measured. Conditional logistic regression was adjusted for confounding variables. Gun suicide risk to individuals in areas of high alcohol outlet availability was less than the gun suicide risk they incurred from acute alcohol consumption, especially to excess. This corroborates prior work but also uncovers new information about the relationships between acute alcohol consumption, alcohol outlets, and gun suicide. Study limitations and implications are discussed. PMID:21929327

Acute alcohol consumption, alcohol outlets, and gun suicide.

PubMed

Branas, Charles C; Richmond, Therese S; Ten Have, Thomas R; Wiebe, Douglas J

2011-01-01

A case-control study of 149 intentionally self-inflicted gun injury cases (including completed gun suicides) and 302 population-based controls was conducted from 2003 to 2006 in a major US city. Two focal independent variables, acute alcohol consumption and alcohol outlet availability, were measured. Conditional logistic regression was adjusted for confounding variables. Gun suicide risk to individuals in areas of high alcohol outlet availability was less than the gun suicide risk they incurred from acute alcohol consumption, especially to excess. This corroborates prior work but also uncovers new information about the relationships between acute alcohol consumption, alcohol outlets, and gun suicide. Study limitations and implications are discussed.

The Gun Violence Prevention Act of 1994: Public Health and Child Safety. Hearing on S. 1882, A Bill To Amend Title 18, United States Code, To Promote the Safe Use of Guns and To Reduce Gun Violence before the Subcommittee on the Constitution of the Committee on the Judiciary. United States Senate, One Hundred Third Congress, Second Session (March 23, 1994).

ERIC Educational Resources Information Center

Congress of the U. S., Washington, DC. Senate Subcommittee on the Constitution.

The first of several hearings on the Gun Violence Prevention Act of 1994 introduced and discussed the Act as comprehensive legislation to address gun violence through six discrete initiatives: (1) handgun licensing; (2) prohibition of firearms possession by persons convicted of violent misdemeanors; (3) regulation of gun dealers; (4) limitation of…

The Armys M-1 Abrams, M-2/M-3 Bradley, and M-1126 Stryker: Background and Issues for Congress

DTIC Science & Technology

2016-04-05

smoothbore gun 1 x coaxial mounted 7.62 mm M-240 machine gun 1 x roof mounted 12.7 mm M-2 HB machine gun 1 x roof mounted 7.62 mm M-240 machine gun 12...Bradley Fighting Vehicle Table 2. Selected Basic Characteristics— M2 /3-A2 Armament 1 x turret mounted M-242 25mm “Bushmaster” chain gun 2 x turret...mounted TOW anti-tank missiles 1 x coaxial mounted 7.62 mm M-240C machine gun 8 x turret mounted smoke grenade launchers Crew M-2: 3 crew, 6

The US gun stock: results from the 2004 national firearms survey.

PubMed

Hepburn, L; Miller, M; Azrael, D; Hemenway, D

2007-02-01

To examine the size and composition of the privately held firearm stock in the US; and to describe demographic patterns of firearm ownership and motivations for ownership. A nationally representative household telephone survey of 2770 adults aged>or=18 years living in the US, conducted in the spring of 2004. Responses to questions regarding firearm ownership, the number and types of guns owned, and motivations for ownership. 38% of households and 26% of individuals reported owning at least one firearm. This corresponds to 42 million US households with firearms, and 57 million adult gun owners. 64% of gun owners or 16% of American adults reported owning at least one handgun. Long guns represent 60% of the privately held gun stock. Almost half (48%) of all individual gun owners reported owning>or=4 firearms. Men more often reported firearm ownership, with 45% stating that they personally owned at least one firearm, compared with 11% for women. The US population continues to contain at least one firearm for every adult, and ownership is becoming increasingly concentrated. Long guns are the most prevalent type of gun in the US but handgun ownership is widespread. Ownership demographic patterns support findings of previous studies.

Law Enforcement and Gun Retailers as Partners for Safely Storing Guns to Prevent Suicide: A Study in 8 Mountain West States.

PubMed

Runyan, Carol W; Brooks-Russell, Ashley; Brandspigel, Sara; Betz, Marian; Tung, Gregory; Novins, Douglas; Agans, Robert

2017-11-01

To examine the extent to which law enforcement agencies (LEAs) and gun retailers are willing to offer voluntary, temporary storage as a part of an overall suicide prevention effort. We invited all LEAs and gun retailers in 8 US states to respond to questionnaires asking about their willingness to offer temporary gun storage and their recommendations to gun owners about safe storage. We collected data in 2016 from 448 LEAs and 95 retailers (response rates of 53% and 25%, respectively). Three quarters of LEAs (74.8%; 95% confidence interval [CI] = 72.1, 77.5) indicated they already provided temporary storage compared with 47.6% (95% CI = 39.2, 56.0) of retailers. LEAs were most willing to provide storage when a gun owner was concerned about the mental health of a family member. Retailers were more receptive than were LEAs to providing storage when visitors were coming or for people wanting storage while traveling. Both groups recommended locking devices within the home, but LEAs were slightly more favorable to storing guns away from the home. Law enforcement agencies and gun retailers are important resources for families concerned about suicide.

US Public Opinion on Carrying Firearms in Public Places.

PubMed

Wolfson, Julia A; Teret, Stephen P; Azrael, Deborah; Miller, Matthew

2017-06-01

To estimate US public opinion, overall and by gun ownership status, about the public places where legal gun owners should be allowed to carry firearms. We fielded an online survey among 3949 adults, including an oversample of gun owners and veterans, in April 2015. We used cross-tabulations with survey weights to generate nationally representative estimates. Fewer than 1 in 3 US adults supported gun carrying in any of the specified venues. Support for carrying in public was consistently higher among gun owners than among non-gun owners. Overall, support for carrying in public was lowest for schools (19%; 95% confidence interval [CI] = 16.7, 21.1), bars (18%; 95% CI = 15.9, 20.6), and sports stadiums (17%; 95% CI = 15.0, 19.5). Most Americans, including most gun owners, support restricting public places legal gun owners can carry firearms. These views contrast sharply with the current trend in state legislatures of expanding where, how, and by whom guns can be carried in public. Recent state laws and proposed federal legislation that would force states to honor out-of-state concealed carry permits are out of step with American public opinion.

Utility of indices of gun availability in the community

PubMed Central

Shenassa, Edmond D; Daskalakis, Constantine; Buka, Stephen L

2006-01-01

Objective To estimate the degree to which the proportion of homicides and suicides committed with a gun is associated with reported availability of firearms across Chicago neighbourhoods. Methods Data were collected as part of the Project on Human Development in Chicago Neighborhoods (PHDCN), a combined neighbourhood and individual level study of the city of Chicago. The study used data from 837 PHDCN participants between the ages of 17 and 22, residing in 170 different neighbourhoods. Gun availability was measured via participant reports on whether they had carried a gun and whether they perceived gun access to be easy in their community. Data on suicides and homicides were obtained from the Chicago Department of Health. Results A 10% change in the proportion of homicides committed by a gun in a neighbourhood was associated with a 20% increase in both the odds of reported gun access and reported gun carrying (p = 0.002 and 0.048, respectively). The proportion of firearm related suicides was not associated with either of those self reported measures. Conclusions The proportion of firearm related homicides, but not the proportion of firearm related suicides, is a useful predictor of gun availability across small areas such as neighbourhoods. PMID:16401610

Utility of indices of gun availability in the community.

PubMed

Shenassa, Edmond D; Daskalakis, Constantine; Buka, Stephen L

2006-01-01

To estimate the degree to which the proportion of homicides and suicides committed with a gun is associated with reported availability of firearms across Chicago neighbourhoods. Data were collected as part of the Project on Human Development in Chicago Neighborhoods (PHDCN), a combined neighbourhood and individual level study of the city of Chicago. The study used data from 837 PHDCN participants between the ages of 17 and 22, residing in 170 different neighbourhoods. Gun availability was measured via participant reports on whether they had carried a gun and whether they perceived gun access to be easy in their community. Data on suicides and homicides were obtained from the Chicago Department of Health. A 10% change in the proportion of homicides committed by a gun in a neighbourhood was associated with a 20% increase in both the odds of reported gun access and reported gun carrying (p=0.002 and 0.048, respectively). The proportion of firearm related suicides was not associated with either of those self reported measures. The proportion of firearm related homicides, but not the proportion of firearm related suicides, is a useful predictor of gun availability across small areas such as neighbourhoods.

International correlations between gun ownership and rates of homicide and suicide.

PubMed Central

Killias, M

1993-01-01

OBJECTIVE: To examine international correlations between reported rates of household gun ownership and rates of homicide and suicide with a gun. DESIGN: Survey. POPULATION: People who responded to a telephone survey conducted by the 1989 International Crime Survey in 11 European countries, Australia, Canada and the United States. RESULTS: Positive correlations were obtained between the rates of household gun ownership and the national rates of homicide and suicide as well as the proportions of homicides and suicides committed with a gun. There was no negative correlation between the rates of ownership and the rates of homicide and suicide committed by other means; this indicated that the other means were not used to "compensate" for the absence of guns in countries with a lower rate of gun ownership. CONCLUSION: Larger studies are needed to examine more closely possible confounding factors such as the national tendency toward violent solutions, and more information on the type and availability of guns will be helpful in future studies. Nevertheless, the correlations detected in this study suggest that the presence of a gun in the home increases the likelihood of homicide or suicide. PMID:8485675

Design and fabrication of two-dimensional semiconducting bolometer arrays for HAWC and SHARC-II

NASA Astrophysics Data System (ADS)

Voellmer, George M.; Allen, Christine A.; Amato, Michael J.; Babu, Sachidananda R.; Bartels, Arlin E.; Benford, Dominic J.; Derro, Rebecca J.; Dowell, C. D.; Harper, D. A.; Jhabvala, Murzy D.; Moseley, S. H.; Rennick, Timothy; Shirron, Peter J.; Smith, W. W.; Staguhn, Johannes G.

2003-02-01

The High resolution Airborne Wideband Camera (HAWC) and the Submillimeter High Angular Resolution Camera II (SHARC II) will use almost identical versions of an ion-implanted silicon bolometer array developed at the National Aeronautics and Space Administration's Goddard Space Flight Center (GSFC). The GSFC "Pop-Up" Detectors (PUD's) use a unique folding technique to enable a 12 × 32-element close-packed array of bolometers with a filling factor greater than 95 percent. A kinematic Kevlar suspension system isolates the 200 mK bolometers from the helium bath temperature, and GSFC - developed silicon bridge chips make electrical connection to the bolometers, while maintaining thermal isolation. The JFET preamps operate at 120 K. Providing good thermal heat sinking for these, and keeping their conduction and radiation from reaching the nearby bolometers, is one of the principal design challenges encountered. Another interesting challenge is the preparation of the silicon bolometers. They are manufactured in 32-element, planar rows using Micro Electro Mechanical Systems (MEMS) semiconductor etching techniques, and then cut and folded onto a ceramic bar. Optical alignment using specialized jigs ensures their uniformity and correct placement. The rows are then stacked to create the 12 × 32-element array. Engineering results from the first light run of SHARC II at the Caltech Submillimeter Observatory (CSO) are presented.

27 CFR 479.105 - Transfer and possession of machine guns.

Code of Federal Regulations, 2012 CFR

2012-04-01

... machine guns. 479.105 Section 479.105 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION MACHINE GUNS, DESTRUCTIVE DEVICES, AND CERTAIN OTHER FIREARMS Registration and Identification of Firearms Machine Guns § 479.105 Transfer...

27 CFR 479.105 - Transfer and possession of machine guns.

Code of Federal Regulations, 2011 CFR

2011-04-01

... machine guns. 479.105 Section 479.105 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION MACHINE GUNS, DESTRUCTIVE DEVICES, AND CERTAIN OTHER FIREARMS Registration and Identification of Firearms Machine Guns § 479.105 Transfer...

27 CFR 479.105 - Transfer and possession of machine guns.

Code of Federal Regulations, 2014 CFR

2014-04-01

... machine guns. 479.105 Section 479.105 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION MACHINE GUNS, DESTRUCTIVE DEVICES, AND CERTAIN OTHER FIREARMS Registration and Identification of Firearms Machine Guns § 479.105 Transfer...

27 CFR 479.105 - Transfer and possession of machine guns.

Code of Federal Regulations, 2010 CFR

2010-04-01

... machine guns. 479.105 Section 479.105 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION MACHINE GUNS, DESTRUCTIVE DEVICES, AND CERTAIN OTHER FIREARMS Registration and Identification of Firearms Machine Guns § 479.105 Transfer...

27 CFR 479.105 - Transfer and possession of machine guns.

Code of Federal Regulations, 2013 CFR

2013-04-01

... machine guns. 479.105 Section 479.105 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION MACHINE GUNS, DESTRUCTIVE DEVICES, AND CERTAIN OTHER FIREARMS Registration and Identification of Firearms Machine Guns § 479.105 Transfer...

Blown Away.

ERIC Educational Resources Information Center

Harrington-Lueker, Donna

1992-01-01

The number of students killed or injured by gunfire while at schools is increasing. The National Rifle Association, the nation's powerful gun lobby, has a gun safety program; however, children's advocates say stricter gun-control laws are necessary. Briefly cites 24 gun incidents and describes 4 semiautomatic pistols that were among the firearms…

Simulations of Gaussian electron guns for RHIC electron lens

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

Pikin, A.

Simulations of two versions of the electron gun for RHIC electron lens are presented. The electron guns have to generate an electron beam with Gaussian radial profile of the electron beam density. To achieve the Gaussian electron emission profile on the cathode we used a combination of the gun electrodes and shaping of the cathode surface. Dependence of electron gun performance parameters on the geometry of electrodes and the margins for electrodes positioning are presented.

Frontline Strategies of the National Rifle Association

DTIC Science & Technology

2006-03-01

in both the House and the Senate and flip control from an anti-gun Democratic leadership to a pro-gun Republican leadership – and I will side track...sympathetic to the rights of gun owners than the Democratic Leadership , I prefer to refer to it as pro-gun majority. This is especially true in US...Republican leadership are all very sympathetic to the rights of gun owners. The Democratic Leadership almost to a person is all very hostile to the

46th Annual Gun and Missile Systems Conference and Exhibition

DTIC Science & Technology

2011-09-01

Grade Sensors Through Use of Accelerated Aging Principles Mr. Scott Gift 11657 Modeling of the Autofrettage Processes of a Gun Barrel Mr. Sudhir...Emissions Measured on the Outer Portion of a Composite Barrel Ms. Rushie Ghimire GUN & MISSILE SYSTEMS ADDITIONAL AUTHORS GUN & MISSILE SYSTEMS...X 3BCT 2BCT X 1BCT TACP COLT • BLUFOR scout squad engaged by enemy infantry and are overwhelmed by heavy machine gun fire 100m to their northwest

The Use of an Electron Microchannel as a Self-Extracting and Focusing Plasma Cathode Electron Gun

NASA Astrophysics Data System (ADS)

Cornish, S.; Khachan, J.

2016-02-01

A new and simple type of electron gun is presented. Unlike conventional electron guns, which require a heated filament or extractor, accelerator and focusing electrodes, this gun uses the collimated electron microchannels of an inertial electrostatic confinement (IEC) discharge to achieve the same outcome. A cylindrical cathode is placed coaxially within a cylindrical anode to create the discharge. Collimated beams of electrons and fast neutrals emerge along the axis of the cylindrical cathode. This geometry isolates one of the microchannels that emerge in a negatively biased IEC grid. The internal operating pressure range of the gun is 35-190 mTorr. A small aperture separates the gun from the main vacuum chamber in order to achieve a pressure differential. The chamber was operated at pressures of 4-12 mTorr. The measured current produced by the gun was 0.1-3 mA (0.2-14 mA corrected measurement) for discharge currents of 1-45 mA and discharge voltages of 0.5-12 kV. The collimated electron beam emerges from the aperture into the vacuum chamber. The performance of the gun is unaffected by the pressure differential between the vacuum chamber and the gun. This allows the aperture to be removed and the chamber pressure to be equal to the gun pressure if required.

Ultra high vacuum test setup for electron gun

NASA Astrophysics Data System (ADS)

Pandiyar, M. L.; Prasad, M.; Jain, S. K.; Kumar, R.; Hannurkar, P. R.

2008-05-01

Ultra High Vacuum (UHV) test setup for electron gun testing has been developed. The development of next generation light sources and accelerators require development of klystron as a radio frequency power source, and in turn electron gun. This UHV electron gun test setup can be used to test the electron guns ranging from high average current, quasi-continuous wave to high peak current, single pulse etc. An electron gun has been designed, fabricated, assembled and tested for insulation up to 80 kV under the programme to develop high power klystron for future accelerators. Further testing includes the electron emission parameters characterization of the cathode, as it determines the development of a reliable and efficient electron gun with high electron emission current and high life time as well. This needs a clean ultra high vacuum to study these parameters particularly at high emission current. The cathode emission current, work function and vapour pressure of cathode surface material at high temperature studies will further help in design and development of high power electron gun The UHV electron gun test setup consists of Turbo Molecular Pump (TMP), Sputter Ion Pump (SIP), pressure gauge, high voltage and cathode power supplies, current measurement device, solenoid magnet and its power supply, residual gas analyser etc. The ultimate vacuum less than 2×10-9 mbar was achieved. This paper describes the UHV test setup for electron gun testing.

RF study and 3-D simulations of a side-coupling thermionic RF-gun

NASA Astrophysics Data System (ADS)

Rimjaem, S.; Kusoljariyakul, K.; Thongbai, C.

2014-02-01

A thermionic RF-gun for generating ultra-short electron bunches was optimized, developed and used as a source at a linac-based THz radiation research laboratory of the Plasma and Beam Physics Research Facility, Chiang Mai University, Thailand. The RF-gun is a π/2-mode standing wave structure, which consists of two S-band accelerating cells and a side-coupling cavity. The 2856 MHz RF wave is supplied from an S-band klystron to the gun through the waveguide input-port at the cylindrical wall of the second cell. A fraction of the RF power is coupled from the second cell to the first one via a side-coupling cavity. Both the waveguide input-port and the side-coupling cavity lead to an asymmetric geometry of the gun. RF properties and electromagnetic field distributions inside the RF-gun were studied and numerically simulated by using computer codes SUPERFISH 7.19 and CST Microwave Studio 2012©. RF characterizations and tunings of the RF-gun were performed to ensure the reliability of the gun operation. The results from 3D simulations and measurements are compared and discussed in this paper. The influence of asymmetric field distributions inside the RF-gun on the electron beam properties was investigated via 3D beam dynamics simulations. A change in the coupling-plane of the side-coupling cavity is suggested to improve the gun performance.

76 FR 29791 - Agency Information Collection Activities; Proposed Collection; Comments Requested: Firearms...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-23

... comments are received is to e-mail them to [email protected] or fax them to 202-395-7285. All..., mechanical, or other technological collection techniques or other forms of information technology, e.g...-profit. Need for Collection The form is used to determine the eligibility (under the Gun Control Act) of...

77 FR 23622 - Approval and Promulgation of Air Quality Implementation Plans; Illinois; Leisure Properties LLC/D...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-20

....regulations.gov index. Although listed in the index, some information is not publicly available, e.g., CBI or... compliance with the Federal Maximum Achievable Control Technology (MACT) limits on volatile organic compounds... by non-atomized guns, and 33.4% HAPs for the gelcoat composition. These emission limits are...

Vehicle Characteristics

DTIC Science & Technology

2008-02-14

g. Material. 5.1.7 Wheel Geometry. a. Camber angle. b. Caster angle. c. Pivot angle. d. Static toe-in. e. Turning angles...the vehicle characteristics to be obtained during testing of wheeled and tracked vehicles and their components. Physical characterization of test...frontal area Characteristic data sheet Power train Suspention Wheel geometry Vehicle clearance angles Armament Gun control systems 16. SECURITY

The Scientific Denial of the Real and the Dialectic of Scientism and Humanism

ERIC Educational Resources Information Center

Ramey, Christopher H.; Chrysikou, Evangelia G.

2005-01-01

This article presents comments on "Realism, Instrumentalism, and Scientific Symbiosis: Psychological Theory as a Search for Truth and the Discovery of Solutions" by John T. Cacioppo, Gun R. Semin and Gary G. Berntson. The appeal for the unification of psychology is in fashion and Cacioppo et al.'s term "symbiosis" connotes a cooperative and…

Modular Low-Heater-Power Cathode/Electron Gun Assembly for Microwave and Millimeter Wave Traveling Wave Tubes

NASA Technical Reports Server (NTRS)

Wintucky, Edwin G.

2000-01-01

A low-cost, low-mass, electrically efficient, modular cathode/electron gun assembly has been developed by FDE Inc. of Beaverton, Oregon, under a Small Business Innovation Research (SBIR) contract with the NASA Glenn Research Center at Lewis Field. This new assembly offers significant improvements in the design and manufacture of microwave and millimeter wave traveling-wave tubes (TWT's) used for radar and communications. It incorporates a novel, low-heater-power, reduced size and mass, high-performance barium dispenser type thermionic cathode and provides for easy integration of the cathode into a large variety of conventional TWT circuits. Among the applications are TWT's for Earth-orbiting communication satellites and for deep space communications, where future missions will require smaller spacecraft, higher data transfer rates (higher frequencies and radiofrequency output power), and greater electrical efficiency. A particularly important TWT application is in the microwave power module (a hybrid microwave/millimeter wave amplifier consisting of a low-noise solid-state driver, a small TWT, and an electronic power conditioner integrated into a single compact package), where electrical efficiency and thermal loading are critical factors and lower cost is needed for successful commercialization. The design and fabrication are based on practices used in producing cathode ray tubes (CRT's), which is one of the most competitive and efficient manufacturing operations in the world today. The approach used in the design and manufacture of thermionic cathodes and electron guns for CRT's has been optimized for fully automated production, standardization of parts, and minimization of costs. It is applicable to the production of similar components for microwave tubes, with the additional benefits of low mass and significantly lower cathode heater power (less than half that of dispenser cathodes presently used in TWT s). Modular cathode/electron gun assembly. The modular cathode/electron gun assembly consists of four subassemblies the cathode, the focus electrode, the header (including the electrical feedthroughs), and the gun envelope (including the anode) a diagram of which is shown. The modular construction offers a number of significant advantages, including flexibility of design, interchangeability of parts, and a drop-in final assembly procedure for quick and accurate alignment. The gun can accommodate cathodes ranging in size from 0.050 to 0.250-in. in diameter and is applicable to TWT's over a broad range of sizes and operating parameters, requiring the substitution of only a few parts: that is, the cathode, focus electrode, and anode. The die-pressed cathode pellets can be made with either flat or concave (Pierce gun design) emitting surfaces. The gun can be either gridded (pulse operation) or ungridded (continuous operation). Important factors contributing to low cost are the greater use of CRT materials and parts, the standardization of processes (welding and mechanical capture), and tooling amenable to automated production. Examples are the use of simple shapes, drawn or stamped metal parts, and parts joined by welding or mechanical capture. Feasibility was successfully demonstrated in the retrofit and testing of a commercial Kaband (22-GHz) TWT. The modular cathode/electron gun assembly was computer modeled to replicate the performance of the original electron gun and fabricated largely from existing CRT parts. Significant test results included demonstration of low heater power (1.5-W, 1010 C brightness temperature for a 0.085-in.-diameter cathode), mechanical ruggedness (100g shock and vibration tests in accordance with military specifications (MIL specs)), and a very fast warmup. The results of these tests indicate that the low-cost CRT manufacturing approach can be used without sacrificing performance and reliability.

Thorium-Free Versus Thoriated Plasma Gun Electrodes: Statistical Evaluation of Coating Properties

NASA Astrophysics Data System (ADS)

Colmenares-Angulo, Jose; Molz, Ronald; Hawley, David; Seshadri, Ramachandran Chidambaram

2016-04-01

Industries throughout the world today have an increased awareness of environmental, health, and safety issues. This, together with recent Nuclear Regulatory Commission changes concerning source material (e.g., thorium) has added complexity in the supply chain of thoriated tungsten commonly used in plasma spray gun spares. In the interest of a safer and more sustainable work environment, Oerlikon Metco has developed thorium-free material solutions proven to have longer service life than conventional thoriated spares. This work reports on the effect, if any, caused by tungsten compositional changes and extended service life in coating properties. Microstructure, coating efficiency parameters, hardness, particle state, in situ coating stress, and ex situ modulus are evaluated over the service life duration of the nozzle, comparing coatings with thoriated and non-thoriated nozzles and electrodes with the same spray parameters.

46 CFR 160.031-3 - Materials, construction, workmanship, and performance requirements.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Appliance, Shoulder Gun Type (and Equipment) § 160.031-3 Materials, construction, workmanship, and performance requirements. (a) All materials used in the construction of shoulder gun type line-throwing... affecting appearance or serviceability of the gun. (d) The gun, when loaded and fired in accordance with the...

46 CFR 160.031-3 - Materials, construction, workmanship, and performance requirements.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Appliance, Shoulder Gun Type (and Equipment) § 160.031-3 Materials, construction, workmanship, and performance requirements. (a) All materials used in the construction of shoulder gun type line-throwing... affecting appearance or serviceability of the gun. (d) The gun, when loaded and fired in accordance with the...

46 CFR 160.031-3 - Materials, construction, workmanship, and performance requirements.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Appliance, Shoulder Gun Type (and Equipment) § 160.031-3 Materials, construction, workmanship, and performance requirements. (a) All materials used in the construction of shoulder gun type line-throwing... affecting appearance or serviceability of the gun. (d) The gun, when loaded and fired in accordance with the...

46 CFR 160.031-3 - Materials, construction, workmanship, and performance requirements.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Appliance, Shoulder Gun Type (and Equipment) § 160.031-3 Materials, construction, workmanship, and performance requirements. (a) All materials used in the construction of shoulder gun type line-throwing... affecting appearance or serviceability of the gun. (d) The gun, when loaded and fired in accordance with the...

46 CFR 160.031-3 - Materials, construction, workmanship, and performance requirements.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Appliance, Shoulder Gun Type (and Equipment) § 160.031-3 Materials, construction, workmanship, and performance requirements. (a) All materials used in the construction of shoulder gun type line-throwing... affecting appearance or serviceability of the gun. (d) The gun, when loaded and fired in accordance with the...

50 CFR 92.20 - Methods and means.

Code of Federal Regulations, 2014 CFR

2014-10-01

... birds: (a) Swivel guns, shotguns larger than 10 gauge, punt guns, battery guns, machine guns, fish hooks, poisons, drugs, explosives, or stupefying substances; (b) Shooting from a sinkbox or any other type of low...) Hunting from any type of aircraft; (d) Taking waterfowl and other species using live birds as decoys...

50 CFR 92.20 - Methods and means.

Code of Federal Regulations, 2012 CFR

2012-10-01

... birds: (a) Swivel guns, shotguns larger than 10 gauge, punt guns, battery guns, machine guns, fish hooks, poisons, drugs, explosives, or stupefying substances; (b) Shooting from a sinkbox or any other type of low...) Hunting from any type of aircraft; (d) Taking waterfowl and other species using live birds as decoys...

50 CFR 92.20 - Methods and means.

Code of Federal Regulations, 2011 CFR

2011-10-01

... birds: (a) Swivel guns, shotguns larger than 10 gauge, punt guns, battery guns, machine guns, fish hooks, poisons, drugs, explosives, or stupefying substances; (b) Shooting from a sinkbox or any other type of low...) Hunting from any type of aircraft; (d) Taking waterfowl and other species using live birds as decoys...

50 CFR 92.20 - Methods and means.

Code of Federal Regulations, 2013 CFR

2013-10-01

... birds: (a) Swivel guns, shotguns larger than 10 gauge, punt guns, battery guns, machine guns, fish hooks, poisons, drugs, explosives, or stupefying substances; (b) Shooting from a sinkbox or any other type of low...) Hunting from any type of aircraft; (d) Taking waterfowl and other species using live birds as decoys...

Advances in light-gas gun technology

NASA Technical Reports Server (NTRS)

Cowan, P. L.; Murphy, J. R.

1968-01-01

Constant-area accelerator used with light-gas guns increases the velocity of accelerating projectiles. A disposable accelerator on the muzzle of the gun uses the energy and momentum of a primary projectile, launched by the gun, to achieve high velocities of a light secondary projectile accelerated from rest in the accelerator.

Micro-Analyzer: automatic preprocessing of Affymetrix microarray data.

PubMed

Guzzi, Pietro Hiram; Cannataro, Mario

2013-08-01

A current trend in genomics is the investigation of the cell mechanism using different technologies, in order to explain the relationship among genes, molecular processes and diseases. For instance, the combined use of gene-expression arrays and genomic arrays has been demonstrated as an effective instrument in clinical practice. Consequently, in a single experiment different kind of microarrays may be used, resulting in the production of different types of binary data (images and textual raw data). The analysis of microarray data requires an initial preprocessing phase, that makes raw data suitable for use on existing analysis platforms, such as the TIGR M4 (TM4) Suite. An additional challenge to be faced by emerging data analysis platforms is the ability to treat in a combined way those different microarray formats coupled with clinical data. In fact, resulting integrated data may include both numerical and symbolic data (e.g. gene expression and SNPs regarding molecular data), as well as temporal data (e.g. the response to a drug, time to progression and survival rate), regarding clinical data. Raw data preprocessing is a crucial step in analysis but is often performed in a manual and error prone way using different software tools. Thus novel, platform independent, and possibly open source tools enabling the semi-automatic preprocessing and annotation of different microarray data are needed. The paper presents Micro-Analyzer (Microarray Analyzer), a cross-platform tool for the automatic normalization, summarization and annotation of Affymetrix gene expression and SNP binary data. It represents the evolution of the μ-CS tool, extending the preprocessing to SNP arrays that were not allowed in μ-CS. The Micro-Analyzer is provided as a Java standalone tool and enables users to read, preprocess and analyse binary microarray data (gene expression and SNPs) by invoking TM4 platform. It avoids: (i) the manual invocation of external tools (e.g. the Affymetrix Power Tools), (ii) the manual loading of preprocessing libraries, and (iii) the management of intermediate files, such as results and metadata. Micro-Analyzer users can directly manage Affymetrix binary data without worrying about locating and invoking the proper preprocessing tools and chip-specific libraries. Moreover, users of the Micro-Analyzer tool can load the preprocessed data directly into the well-known TM4 platform, extending in such a way also the TM4 capabilities. Consequently, Micro Analyzer offers the following advantages: (i) it reduces possible errors in the preprocessing and further analysis phases, e.g. due to the incorrect choice of parameters or due to the use of old libraries, (ii) it enables the combined and centralized pre-processing of different arrays, (iii) it may enhance the quality of further analysis by storing the workflow, i.e. information about the preprocessing steps, and (iv) finally Micro-Analzyer is freely available as a standalone application at the project web site http://sourceforge.net/projects/microanalyzer/. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

The Role of FcRn in Antigen Presentation

PubMed Central

Baker, Kristi; Rath, Timo; Pyzik, Michal; Blumberg, Richard S.

2014-01-01

Immunoglobulins are unique molecules capable of simultaneously recognizing a diverse array of antigens and themselves being recognized by a broad array of receptors. The abundance specifically of the IgG subclass and the variety of signaling receptors to which it binds render this an important immunomodulatory molecule. In addition to the classical Fcγ receptors that bind IgG at the cell surface, the neonatal Fc receptor (FcRn) is a lifelong resident of the endolysosomal system of most hematopoietic cells where it determines the intracellular fate of both IgG and IgG-containing immune complexes (IgG IC). Cross-linking of FcRn by multivalent IgG IC within antigen presenting cells such as dendritic cells initiates specific mechanisms that result in trafficking of the antigen-bearing IgG IC into compartments from which the antigen can successfully be processed into peptide epitopes compatible with loading onto both major histocompatibility complex class I and II molecules. In turn, this enables the synchronous activation of both CD4+ and CD8+ T cell responses against the cognate antigen, thereby bridging the gap between the humoral and cellular branches of the adaptive immune response. Critically, FcRn-driven T cell priming is efficient at very low doses of antigen due to the exquisite sensitivity of the IgG-mediated antigen delivery system through which it operates. FcRn-mediated antigen presentation has important consequences in tissue compartments replete with IgG and serves not only to determine homeostatic immune activation at a variety of sites but also to induce inflammatory responses upon exposure to antigens perceived as foreign. Therapeutically targeting the pathway by which FcRn enables T cell activation in response to IgG IC is thus a highly attractive prospect not only for the treatment of diseases that are driven by immune complexes but also for manipulating local immune responses against defined antigens such as those present during infections and cancer. PMID:25221553

Tectonic Inversion Along the Algerian and Ligurian Margins: On the Insight Provided By Latest Seismic Processing Techniques Applied to Recent and Vintage 2D Offshore Multichannel Seismic Data

NASA Astrophysics Data System (ADS)

Schenini, L.; Beslier, M. O.; Sage, F.; Badji, R.; Galibert, P. Y.; Lepretre, A.; Dessa, J. X.; Aidi, C.; Watremez, L.

2014-12-01

Recent studies on the Algerian and the North-Ligurian margins in the Western Mediterranean have evidenced inversion-related superficial structures, such as folds and asymmetric sedimentary perched basins whose geometry hints at deep compressive structures dipping towards the continent. Deep seismic imaging of these margins is difficult due to steep slope and superficial multiples, and, in the Mediterranean context, to the highly diffractive Messinian evaporitic series in the basin. During the Algerian-French SPIRAL survey (2009, R/V Atalante), 2D marine multi-channel seismic (MCS) reflection data were collected along the Algerian Margin using a 4.5 km, 360 channel digital streamer and a 3040 cu. in. air-gun array. An advanced processing workflow has been laid out using Geocluster CGG software, which includes noise attenuation, 2D SRME multiple attenuation, surface consistent deconvolution, Kirchhoff pre-stack time migration. This processing produces satisfactory seismic images of the whole sedimentary cover, and of southward dipping reflectors in the acoustic basement along the central part of the margin offshore Great Kabylia, that are interpreted as inversion-related blind thrusts as part of flat-ramp systems. We applied this successful processing workflow to old 2D marine MCS data acquired on the North-Ligurian Margin (Malis survey, 1995, R/V Le Nadir), using a 2.5 km, 96 channel streamer and a 1140 cu. in. air-gun array. Particular attention was paid to multiple attenuation in adapting our workflow. The resulting reprocessed seismic images, interpreted with a coincident velocity model obtained by wide-angle data tomography, provide (1) enhanced imaging of the sedimentary cover down to the top of the acoustic basement, including the base of the Messinian evaporites and the sub-salt Miocene series, which appear to be tectonized as far as in the mid-basin, and (2) new evidence of deep crustal structures in the margin which the initial processing had failed to reveal.

Historical Simulation and the American Civil War.

DTIC Science & Technology

1991-06-07

book, Little Wars. Wells’ game used a toy gun firing wooden bullets to inflict casualties. His tactics involved positioning of guns , proper use of cover...Confederates initiated the game -turn by concen- trating the fire of 14 guns against Kleiser’s 6 gun battery causing one casting casualty. At the...brought in flanking fire on Wynkoop’s and Tibbit’s cavalry brigades. Imboden claimed, "The effect was magical . The first discharge of the gun threw his

EXPERIMENTS WITH PLASMA RINGS

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

Alfven, H.; Lindberg, L.; Mitlid, P.

1960-03-01

The construction of a coaxial plasma gun is described. At its output end the gun is provided with a radial magnetic field, which is trapped by the plasma. The plasma from the gun is studied by photographic and magnetic methods. It is demonstrated that the gun produces magnetized plasma rings with the same basic structure as the rings obtained in toroidal pinch experiments. When the plasma rings are formed, the magnetic field lines from the gun break, a result which is of interest from a theoretical point of view. (auth)

Cost Estimate for Gun Liner Emplacement

DTIC Science & Technology

2011-08-01

material. The M2 machine gun has a Stellite 21 liner that covers only about one-half of the barrel length. It has been successful in reducing the...Michael R. M2 Machine Gun Barrel Wear with SLAP Ammunition. To be published in Journal of Materials and Manufacturing Processes. 8. Miller, Mark D...case in point is the use of a Stellite 21 liner in the M2 0.50-cal machine gun . However, liners have generally been difficult to place into gun tubes

Planning Support for Maintenance and Overhaul of Gun Weapon Systems

DTIC Science & Technology

1981-05-01

13 (shielded twin) gun mounts are targeted to receive ORDALTs 9335 and 9409. Sixty-seven ship hulls are involved in the program, for a total of 147...gun mounts (excluding four training mounts ). Seventy-three Mod 0 and seventy-four Mod 13 gun mounts are included in the program, for an estimated total ...of gun mounts included in the GWSIP. Each mount will receive one amplifier ORDALT, for a. a total of 147, and two upgraded oscillating assemblies

Balancing Mitigation Against Impact: A Case Study From the 2005 Chicxulub Seismic Survey

NASA Astrophysics Data System (ADS)

Barton, P.; Diebold, J.; Gulick, S.

2006-05-01

In early 2005 the R/V Maurice Ewing conducted a large-scale deep seismic reflection-refraction survey offshore Yucatan, Mexico, to investigate the internal structure of the Chicxulub impact crater, centred on the coastline. Shots from a tuned 20 airgun, 6970 cu in array were recorded on a 6 km streamer and 25 ocean bottom seismometers (OBS). The water is exceptionally shallow to large distances offshore, reaching 30 m about 60 km from the land, making it unattractive to the larger marine mammals, although there are small populations of Atlantic and spotted dolphins living in the area, as well as several turtle breeding and feeding grounds on the Yucatan peninsula. In the light of calibrated tests of the Ewing's array (Tolstoy et al., 2004, Geophysical Research Letters 31, L14310), a 180 dB safety radius of 3.5 km around the gun array was adopted. An energetic campaign was organised by environmentalists opposing the work. In addition to the usual precautions of visual and listening watches by independent observers, gradual ramp-ups of the gun arrays, and power-downs or shut-downs for sightings, constraints were also placed to limit the survey to daylight hours and weather conditions not exceeding Beaufort 4. The operations were subject to several on-board inspections by the Mexican environmental authorities, causing logistical difficulties. Although less than 1% of the total working time was lost to shutdowns due to actual observation of dolphins or turtles, approximately 60% of the cruise time was taken up in precautionary inactivity. A diver in the water 3.5 km from the profiling ship reported that the sound in the water was barely noticeable, leading us to examine the actual sound levels recorded by both the 6 km streamer and the OBS hydrophones. The datasets are highly self-consistent, and give the same pattern of decay with distance past about 2 km offset, but with different overall levels: this may be due to geometry or calibration differences under investigation. Both datasets indicate significantly lower levels than reported by Tolstoy et al. (2004). There was no evidence of environmental damage created by this survey. It can be concluded that the mitigation measures were extremely successful, but there is also a concern that the overhead cost of the environmental protection made this one of the most costly academic surveys ever undertaken, and that not all of this protection was necessary. In particular, the predicted 180 dB safety radius appeared to be overly conservative, even though based on calibrated measurements in very similar physical circumstances, and we suggest that these differences were a result of local seismic velocity structure in the water column and/or shallow seabed, which resulted in different partitioning of the energy. These results suggest that real time monitoring of hydrophone array data may provide a method of determining the safety radius dynamically, in response to local conditions.

Do Guns in the Home Predict Gender and Relationship Attitudes? An Exploratory Study

PubMed Central

Follingstad, Diane R.; Coker, Ann L.; Chahal, Jaspreet K.; Brancato, Candace J.; Bush, Heather M.

2017-01-01

This study explores the potential relationship of guns in students’ homes with attitudes indicative of tolerance of violence, negative attitudes toward women and their roles, and attitudes suggestive of myths regarding sexual assault. Seniors in Kentucky high schools whose families possessed guns (N=1749) produced higher scores on scales measuring these variables as well as on scales of relationship dependency and religious involvement than seniors whose families did not own guns (N=912). Students whose families owned more than 10 guns tended to score highest on these measures compared with students whose families owned no or a few guns. Because of lower effect sizes, these significant associations require further investigation. PMID:29081646

Low-energy plasma-cathode electron gun with a perforated emission electrode

NASA Astrophysics Data System (ADS)

Burdovitsin, Victor; Kazakov, Andrey; Medovnik, Alexander; Oks, Efim; Tyunkov, Andrey

2017-11-01

We describe research of influence of the geometric parameters of perforated electrode on emission parameters of a plasma cathode electron gun generating continuous electron beams at gas pressure 5-6 Pa. It is shown, that the emission current increases with increasing the hole diameters and decreasing the thickness of the perforated emission electrode. Plasma-cathode gun with perforated electron can provide electron extraction with an efficiency of up to 72 %. It is shown, that the current-voltage characteristic of the electron gun with a perforated emission electrode differs from that of similar guns with fine mesh grid electrode. The plasma-cathode electron gun with perforated emission electrode is used for electron beam welding and sintering.

Compound heterozygous NEK1 variants in two siblings with oral-facial-digital syndrome type II (Mohr syndrome)

PubMed Central

Monroe, Glen R; Kappen, Isabelle FPM; Stokman, Marijn F; Terhal, Paulien A; van den Boogaard, Marie-José H; Savelberg, Sanne MC; van der Veken, Lars T; van Es, Robert JJ; Lens, Susanne M; Hengeveld, Rutger C; Creton, Marijn A; Janssen, Nard G; Mink van der Molen, Aebele B; Ebbeling, Michelle B; Giles, Rachel H; Knoers, Nine V; van Haaften, Gijs

2016-01-01

The oral-facial-digital (OFD) syndromes comprise a group of related disorders with a combination of oral, facial and digital anomalies. Variants in several ciliary genes have been associated with subtypes of OFD syndrome, yet in most OFD patients the underlying cause remains unknown. We investigated the molecular basis of disease in two brothers with OFD type II, Mohr syndrome, by performing single-nucleotide polymorphism (SNP)-array analysis on the brothers and their healthy parents to identify homozygous regions and candidate genes. Subsequently, we performed whole-exome sequencing (WES) on the family. Using WES, we identified compound heterozygous variants c.[464G>C][1226G>A] in NIMA (Never in Mitosis Gene A)-Related Kinase 1 (NEK1). The novel variant c.464G>C disturbs normal splicing in an essential region of the kinase domain. The nonsense variant c.1226G>A, p.(Trp409*), results in nonsense-associated alternative splicing, removing the first coiled-coil domain of NEK1. Candidate variants were confirmed with Sanger sequencing and alternative splicing assessed with cDNA analysis. Immunocytochemistry was used to assess cilia number and length. Patient-derived fibroblasts showed severely reduced ciliation compared with control fibroblasts (18.0 vs 48.9%, P<0.0001), but showed no significant difference in cilia length. In conclusion, we identified compound heterozygous deleterious variants in NEK1 in two brothers with Mohr syndrome. Ciliation in patient fibroblasts is drastically reduced, consistent with a ciliary defect pathogenesis. Our results establish NEK1 variants involved in the etiology of a subset of patients with OFD syndrome type II and support the consideration of including (routine) NEK1 analysis in patients suspected of OFD. PMID:27530628

Compound heterozygous NEK1 variants in two siblings with oral-facial-digital syndrome type II (Mohr syndrome).

PubMed

Monroe, Glen R; Kappen, Isabelle Fpm; Stokman, Marijn F; Terhal, Paulien A; van den Boogaard, Marie-José H; Savelberg, Sanne Mc; van der Veken, Lars T; van Es, Robert Jj; Lens, Susanne M; Hengeveld, Rutger C; Creton, Marijn A; Janssen, Nard G; Mink van der Molen, Aebele B; Ebbeling, Michelle B; Giles, Rachel H; Knoers, Nine V; van Haaften, Gijs

2016-12-01

The oral-facial-digital (OFD) syndromes comprise a group of related disorders with a combination of oral, facial and digital anomalies. Variants in several ciliary genes have been associated with subtypes of OFD syndrome, yet in most OFD patients the underlying cause remains unknown. We investigated the molecular basis of disease in two brothers with OFD type II, Mohr syndrome, by performing single-nucleotide polymorphism (SNP)-array analysis on the brothers and their healthy parents to identify homozygous regions and candidate genes. Subsequently, we performed whole-exome sequencing (WES) on the family. Using WES, we identified compound heterozygous variants c.[464G>C];[1226G>A] in NIMA (Never in Mitosis Gene A)-Related Kinase 1 (NEK1). The novel variant c.464G>C disturbs normal splicing in an essential region of the kinase domain. The nonsense variant c.1226G>A, p.(Trp409*), results in nonsense-associated alternative splicing, removing the first coiled-coil domain of NEK1. Candidate variants were confirmed with Sanger sequencing and alternative splicing assessed with cDNA analysis. Immunocytochemistry was used to assess cilia number and length. Patient-derived fibroblasts showed severely reduced ciliation compared with control fibroblasts (18.0 vs 48.9%, P<0.0001), but showed no significant difference in cilia length. In conclusion, we identified compound heterozygous deleterious variants in NEK1 in two brothers with Mohr syndrome. Ciliation in patient fibroblasts is drastically reduced, consistent with a ciliary defect pathogenesis. Our results establish NEK1 variants involved in the etiology of a subset of patients with OFD syndrome type II and support the consideration of including (routine) NEK1 analysis in patients suspected of OFD.

Effect of transverse magnetic fields on a simulated in-line 6 MV linac

NASA Astrophysics Data System (ADS)

St. Aubin, J.; Steciw, S.; Fallone, B. G.

2010-08-01

The effects of a transverse magnetic field on an in-line side-coupled 6 MV linear accelerator are given. The results are directly applicable to a linac-MR system used for real-time image guided adaptive radiotherapy. Our previously designed end-to-end linac simulation incorporated the results from the axisymmetric 2D electron gun program EGN2w. However, since the magnetic fields being investigated are non-axisymmetric in nature for the work presented here, the electron gun simulation was performed using OPERA-3d/SCALA. The simulation results from OPERA-3d/SCALA showed excellent agreement with previous results. Upon the addition of external magnetic fields to our fully 3D linac simulation, it was found that a transverse magnetic field of 6 G resulted in a 45 ± 1% beam loss, and by 14 G, no electrons were incident on the target. Transverse magnetic fields on the linac simulation produced a highly asymmetric focal spot at the target, which translated into a 13% profile asymmetry at 6 G. Upon translating the focal spot with respect to the target coordinates, profile symmetry was regained at the expense of a lateral shift in the dose profiles. It was found that all points in the penumbra failed a 1%/1 mm acceptance criterion for fields between 4 and 6 G. However, it was also found that the lateral profile shifts were corrected by adjusting the jaw positions asymmetrically.

Media Agenda Setting Regarding Gun Violence before and after a Mass Shooting

PubMed Central

Jashinsky, Jared Michael; Magnusson, Brianna; Hanson, Carl; Barnes, Michael

2017-01-01

Gun violence is related to substantial morbidity and mortality with surrounding discussions framed and shaped by the media. This study’s objective was to explore national news media’s reporting of gun violence around a mass shooting. National news pieces were coded according to categories of gun violence, media frames, entities held responsible, responses, and reporting of the public heath approach. Individuals were held responsible for gun violence in 63% of pieces before and 32% after the shooting. Lawmakers were held responsible in 30% of pieces before and 66% after. Background checks were a proposed gun violence prevention method in 18% of pieces before and 55% after Sandy Hook, and lethality reduction of firearms was in 9% before and 57% after. Following a mass shooting, the media tended to hold government, not individuals, primarily responsible. The media often misrepresented the real picture of gun violence and key public health roles. PMID:28119907

X-Band RF Gun Development

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

Vlieks, Arnold; Dolgashev, Valery; Tantawi, Sami

In support of the MEGa-ray program at LLNL and the High Gradient research program at SLAC, a new X-band multi-cell RF gun is being developed. This gun, similar to earlier guns developed at SLAC for Compton X-ray source program, will be a standing wave structure made of 5.5 cells operating in the pi mode with copper cathode. This gun was designed following criteria used to build SLAC X-band high gradient accelerating structures. It is anticipated that this gun will operate with surface electric fields on the cathode of 200 MeV/m with low breakdown rate. RF will be coupled into themore » structure through a final cell with symmetric duel feeds and with a shape optimized to minimize quadrupole field components. In addition, geometry changes to the original gun, operated with Compton X-ray source, will include a wider RF mode separation, reduced surface electric and magnetic fields.« less

Carbon Nanotube Electron Gun

NASA Technical Reports Server (NTRS)

Ribaya, Bryan P. (Inventor); Nguyen, Cattien V. (Inventor)

2013-01-01

An electron gun, an electron source for an electron gun, an extractor for an electron gun, and a respective method for producing the electron gun, the electron source and the extractor are disclosed. Embodiments provide an electron source utilizing a carbon nanotube (CNT) bonded to a substrate for increased stability, reliability, and durability. An extractor with an aperture in a conductive material is used to extract electrons from the electron source, where the aperture may substantially align with the CNT of the electron source when the extractor and electron source are mated to form the electron gun. The electron source and extractor may have alignment features for aligning the electron source and the extractor, thereby bringing the aperture and CNT into substantial alignment when assembled. The alignment features may provide and maintain this alignment during operation to improve the field emission characteristics and overall system stability of the electron gun.

Fatalities caused by spherical bullets fired from blank cartridge guns in Istanbul, Turkey.

PubMed

Uzün, Ibrahim; Büyük, Yalçin; Erkol, Zerrin; Ağritmiş, Hasan; Kir, Ziya

2009-09-01

Blank cartridge guns are generally regarded as being harmless and are not considered to be firearms in the legal sense in most countries. To show the danger of these guns upon simple modifications, we report 59 fatalities resulting from these simply modified blank cartridge guns in Istanbul, Turkey. The great majority of the victims were males and the age of those ranged from 11 to 61 years. In 55.9% of these cases, homicide was the origin followed by suicide (39%). The right temporal region was detected to be the preferred region in suicidal shots by blank cartridge guns with a frequency of 56.5%. In trial shots, all these guns were detected to discharge steel or lead spherical objects, generally 4 or 5 mm in diameter, successfully. Our findings strongly suggest that these guns should also be considered as handguns in the legal sense.

Carbon nanotube electron gun

NASA Technical Reports Server (NTRS)

Nguyen, Cattien V. (Inventor); Ribaya, Bryan P. (Inventor)

2010-01-01

An electron gun, an electron source for an electron gun, an extractor for an electron gun, and a respective method for producing the electron gun, the electron source and the extractor are disclosed. Embodiments provide an electron source utilizing a carbon nanotube (CNT) bonded to a substrate for increased stability, reliability, and durability. An extractor with an aperture in a conductive material is used to extract electrons from the electron source, where the aperture may substantially align with the CNT of the electron source when the extractor and electron source are mated to form the electron gun. The electron source and extractor may have alignment features for aligning the electron source and the extractor, thereby bringing the aperture and CNT into substantial alignment when assembled. The alignment features may provide and maintain this alignment during operation to improve the field emission characteristics and overall system stability of the electron gun.

Yield and complications in percutaneous renal biopsy. A comparison between ultrasound-guided gun-biopsy and manual techniques in native and transplant kidneys.

PubMed

Nyman, R S; Cappelen-Smith, J; al Suhaibani, H; Alfurayh, O; Shakweer, W; Akhtar, M

1997-05-01

To compare the yield and complications of ultrasound-guided gun-biopsy and manual Tru-Cut techniques in percutaneous renal biopsy. A total of 448 biopsies were reviewed. They comprised 124 manual and 131 gun-biopsies in native kidneys, and 111 manual and 82 gun-biopsies in transplant kidneys. The gun-biopsies were performed under real-time ultrasound (US) guidance. The manual technique used US mainly for marking the position of the kidney. There was a significantly higher diagnostic yield and fewer complications in the gun-biopsy group. A total of 8 major complications were found, all in the manual group. Provided that the operator is experienced in US scanning, a switch from the manual technique to real-time US-guided gun-biopsy will result in the improvement of diagnostic accuracy together with a reduced risk of complications.

Media Agenda Setting Regarding Gun Violence before and after a Mass Shooting.

PubMed

Jashinsky, Jared Michael; Magnusson, Brianna; Hanson, Carl; Barnes, Michael

2016-01-01

Gun violence is related to substantial morbidity and mortality with surrounding discussions framed and shaped by the media. This study's objective was to explore national news media's reporting of gun violence around a mass shooting. National news pieces were coded according to categories of gun violence, media frames, entities held responsible, responses, and reporting of the public heath approach. Individuals were held responsible for gun violence in 63% of pieces before and 32% after the shooting. Lawmakers were held responsible in 30% of pieces before and 66% after. Background checks were a proposed gun violence prevention method in 18% of pieces before and 55% after Sandy Hook, and lethality reduction of firearms was in 9% before and 57% after. Following a mass shooting, the media tended to hold government, not individuals, primarily responsible. The media often misrepresented the real picture of gun violence and key public health roles.

Mechanical design and fabrication of the VHF-gun, the Berkeley normal-conducting continuous-wave high-brightness electron source

NASA Astrophysics Data System (ADS)

Wells, R. P.; Ghiorso, W.; Staples, J.; Huang, T. M.; Sannibale, F.; Kramasz, T. D.

2016-02-01

A high repetition rate, MHz-class, high-brightness electron source is a key element in future high-repetition-rate x-ray free electron laser-based light sources. The VHF-gun, a novel low frequency radio-frequency gun, is the Lawrence Berkeley National Laboratory (LBNL) response to that need. The gun design is based on a normal conducting, single cell cavity resonating at 186 MHz in the VHF band and capable of continuous wave operation while still delivering the high accelerating fields at the cathode required for the high brightness performance. The VHF-gun was fabricated and successfully commissioned in the framework of the Advanced Photo-injector EXperiment, an injector built at LBNL to demonstrate the capability of the gun to deliver the required beam quality. The basis for the selection of the VHF-gun technology, novel design features, and fabrication techniques are described.

Mechanical design and fabrication of the VHF-gun, the Berkeley normal-conducting continuous-wave high-brightness electron source.

PubMed

Wells, R P; Ghiorso, W; Staples, J; Huang, T M; Sannibale, F; Kramasz, T D

2016-02-01

A high repetition rate, MHz-class, high-brightness electron source is a key element in future high-repetition-rate x-ray free electron laser-based light sources. The VHF-gun, a novel low frequency radio-frequency gun, is the Lawrence Berkeley National Laboratory (LBNL) response to that need. The gun design is based on a normal conducting, single cell cavity resonating at 186 MHz in the VHF band and capable of continuous wave operation while still delivering the high accelerating fields at the cathode required for the high brightness performance. The VHF-gun was fabricated and successfully commissioned in the framework of the Advanced Photo-injector EXperiment, an injector built at LBNL to demonstrate the capability of the gun to deliver the required beam quality. The basis for the selection of the VHF-gun technology, novel design features, and fabrication techniques are described.