108 research outputs found
Fabrication of planarized small area Nb/Al,AlO<sub>x</sub>/Al/Nb Josephson tunnel junctions using reactive ion etching in SF<sub>6</sub>
High quality Nb/Al,AlOx/Al/Nb Josephson tunnel junctions have been made with the help of a fabrication process based on reactive ion etching of Nb in SF6. The Vm value of these junctions is typically 60–70 mV at 4.2 K. At 1.6 K, a Vm of 4.1 V has been measured, which is the highest value that has ever been reported for this type of junction. The area of the junctions ranges from 1 to 25 μm2. By burying the Nb/Al,AlOx/Al/Nb trilayer in the substrate, a planarized junction configuration has been obtained. Reactive ion etching of Nb in SF6 plasmas has been studied in detail. Anisotropic etch profiles can be obtained because of the formation of a resistant layer during etching, which prevents etching of Nb under the photoresist. The etching process has been monitored with a spectrometer. The fluorine emission at 703.7 nm is shown to be suitable for end point detection
Sentencing Outcomes of Convicted Child Sex Offenders
This research examines the sentencing outcomes of convicted child sexual offenders from data collected over an eight year period. Multiple regression and nominal log linear regression are used to examine length of prison sentence, length of probation sentence, and whether or not the convicted offender is actually sent to prison or to probation. While many independent variables appear to be related to sentence outcome, they fall into three categories: characteristics of the offender, characteristics of the victim, and characteristics of the crime. Additionally, while many variables appear related at the bivariate level, when multivariate analysis is applied, fewer variables remain significant and these are mostly from the characteristics of the offense
Drift Chamber Utilizing Microstrip Readout for Testing a New Micro TPC Concept
A drift chamber type radiation detector is being used to examine design criteria for a new type of detector called a micro Time Projection Chamber (micro TPC) which is being proposed for use in high energy nuclear physics experiments. The main advantage of the micro TPC detector is its very low radiation thickness compared to its silicon counterpart. The micro TPC is a charged-particle detector which willbe optimized for good two track resolution which is needed inahigh track density environment. Such performance requires low electron diffusion and high resolution readout. The diffusion willbe reduced bylimiting the drift distance to 15 cm and by using a low diffusion gas such as dimethyl ether. High resolution willbe obtained by using a new readout technology called microstrips. Microstrips are a recent development using photolithography techniques that allow the creation of anodes a few microns in width with submicron precision. The main purpose of this test chamber is to demonstrate the feasibility of a micro TPC design using a low diffusion gas and to insure the sufficient signal remains after electron attenuation. The driftchamber design and the proposed testingprocedures are described
Neutrons from multiplicity-selected Au-Au collisions at 150, 250, 400, and 650 AMeV
We measured neutron triple-differential cross sections from
multiplicity-selected Au-Au collisions at 150, 250, 400, and 650 \AMeV. The
reaction plane for each collision was estimated from the summed transverse
velocity vector of the charged fragments emitted in the collision. We examined
the azimuthal distribution of the triple-differential cross sections as a
function of the polar angle and the neutron rapidity. We extracted the average
in--plane transverse momentum and the normalized
observable , where is the neutron
transverse momentum, as a function of the neutron center-of-mass rapidity, and
we examined the dependence of these observables on beam energy. These
collective flow observables for neutrons, which are consistent with those of
protons plus bound nucleons from the Plastic Ball Group, agree with the
Boltzmann--Uehling--Uhlenbeck (BUU) calculations with a momentum--dependent
interaction. Also, we calculated the polar-angle-integrated maximum azimuthal
anisotropy ratio R from the value of .Comment: 20 LaTeX pages. 11 figures to be faxed on request, send email to
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Leaving behind the ‘total institution’? Teeth, transcarceral spaces and (re)inscription of the formerly incarcerated body
Immune modulation by group B Streptococcus influences host susceptibility to urinary tract infection by uropathogenic Escherichia coli
Urinary tract infection (UTI) is most often caused by uropathogenic Escherichia coli (UPEC). UPEC inoculation into the female urinary tract (UT) can occur through physical activities that expose the UT to an inherently polymicrobial periurethral, vaginal, or gastrointestinal flora. We report that a common urogenital inhabitant and opportunistic pathogen, group B Streptococcus (GBS), when present at the time of UPEC exposure, undergoes rapid UPEC-dependent exclusion from the murine urinary tract, yet it influences acute UPEC-host interactions and alters host susceptibility to persistent outcomes of bladder and kidney infection. GBS presence results in increased UPEC titers in the bladder lumen during acute infection and reduced inflammatory responses of murine macrophages to live UPEC or purified lipopolysaccharide (LPS), phenotypes that require GBS mimicry of host sialic acid residues. Taken together, these studies suggest that despite low titers, the presence of GBS at the time of polymicrobial UT exposure may be an overlooked risk factor for chronic pyelonephritis and recurrent UTI in susceptible groups, even if it is outcompeted and thus absent by the time of diagnosis
Factors affecting the outcome of surgically treated non-iatrogenic traumatic cervical esophageal perforation: 28 years experience at a single center
<p>Abstract</p> <p>Background</p> <p>We reviewed our experience with non-iatrogenic traumatic cervical esophageal perforations, paying particular attention to factors affecting the outcome of such cases.</p> <p>Methods</p> <p>In total, 30 patients treated surgically between 1980 and 2008 for non-iatrogenic traumatic cervical esophageal perforation in our clinic were reviewed.</p> <p>Results</p> <p>There were 25 male and 5 female patients with a median age of 27.5 years. The type of injury was external trauma in 21 (70%) patients and endoluminal injury in the remaining 9 (30%) patients. The mechanism of injury was gunshot in 16 patients, stabbing in 4, falling in 1 (extraluminal injury), and foreign body in 9 (endoluminal injuries). The overall mortality rate was 16.6% (5/30). The mortality rate for extraluminal injuries was 19%, and for endoluminal injuries was 11.1%. Mortality in patients treated within 24 h of sustaining injury was substantially less than in those for whom diagnosis and treatment were delayed (12.5 and 21.4%, respectively). The mortality rate was 33.3% (3/9) for patients with tracheal injuries and 9.5% (2/21) for those without tracheal injuries.</p> <p>Conclusions</p> <p>A treatment delay greater than 24 h, the presence of tracheal injury, or extraluminal perforation significantly affected the outcome of surgically treated non iatrogenic traumatic cervical esophageal perforation.</p
Currency Unions
A currency union is when several independent sovereign nations share a common currency. This has been a recurring phenomenon in monetary history. In this article I study the theoretical foundations of such unions, and discuss some important currency unions in history, most notably the case of the US. Finally I contrast the design of the EMU with economic theories and historical experiences of currency unions
Laser produced electromagnetic pulses : Generation, detection and mitigation
This paper provides an up-to-date review of the problems related to the generation, detection and mitigation of strong electromagnetic pulses created in the interaction of high-power, high-energy laser pulses with different types of solid targets. It includes new experimental data obtained independently at several international laboratories. The mechanisms of electromagnetic field generation are analyzed and considered as a function of the intensity and the spectral range of emissions they produce. The major emphasis is put on the gHz frequency domain, which is the most damaging for electronics and may have important applications. The physics of electromagnetic emissions in other spectral domains, in particular THz and MHz, is also discussed. The theoretical models and numerical simulations are compared with the results of experimental measurements, with special attention to the methodology of measurements and complementary diagnostics. Understanding the underlying physical processes is the basis for developing techniques to mitigate the electromagnetic threat and to harness electromagnetic emissions, which may have promising applications
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