921 research outputs found
SOME FORENSIC ASPECTS OF BALLISTIC IMAGING
Analysis of ballistics evidence (spent cartridge casings and bullets) has been a staple of forensic criminal investigation for almost a century. Computer-assisted databases of images of ballistics evidence have been used since the mid-1980s to help search for potential matches between pieces of evidence. In this article, we draw on the 2008 National Research Council Report Ballistic Imaging to assess the state of ballistic imaging technology. In particular, we discuss the feasibility of creating a national reference ballistic imaging database (RBID) from test-fires of all newly manufactured or imported firearms. A national RBID might aid in using crime scene ballistic evidence to generate investigative leads to a crime gun’s point of sale. We conclude that a national RBID is not feasible at this time, primarily because existing imaging methodologies have insufficient discriminatory power. We also examine the emerging technology of micro- stamping for forensic identification purposes: etching a known identifier on firearm or ammunition parts so that they can be directly read and recovered from crime scene evidence. Microstamping could provide a stronger basis for identification based on ballistic evidence than the status quo, but substantial further research is needed to thoroughly assess its practical viability
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Overview and status of the 0.5NA EUV microfield exposure tool at Berkeley Lab
A 0.5-NA extreme ultraviolet micro-field exposure tool has been installed and commissioned at beamline 12.0.1.4 of the Advanced Light Source synchrotron facility at Lawrence Berkeley National Laboratory. Commissioning has demonstrated a patterning resolution of 13 nm half-pitch with annular 0.35-0.55 illumination; a patterning resolution of 8 nm half-pitch with annular 0.1-0.2 illumination; critical dimension (CD) uniformity of 0.7 nm 1σ on 16 nm nominal CD across 80% of the 200 um x 30 um aberration corrected field of view; aerial image vibration relative to the wafer of 0.75 nn RMS and focus control and focus stepping better than 15 nm
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Comparison of different trap designs for capture of noctuid moths (Lepidoptera: Noctuidae) with pheromone and floral odor attractants
Six trap designs were assessed for capturing noctuid moths in field trials in the UK and Argentina. The traps were baited with either a sex pheromone for Autographa gamma in the UK trials and Helicoverpa gelotopoeon in Argentina, or a floral odor blend. In the UK trials the Universal Trap and a funnel sleeve trap were compared; in Argentina the funnel sleeve trap, a homemade bucket trap, and three sticky traps: LepTrap, wing trap, and delta trap were compared. Comparisons were made between the traps and attractants and captures of noctuid moths and non-target insects. Traps baited with the floral attractant caught a lower number but a wider range of noctuid species including Helicoverpa, Spodoptera, Rachiplusia, Dargida, Mythimna, Chrysodeixis, Agrotis, and Autographa spp, and non-target insects. In the UK trials, the funnel sleeve trap caught significantly more A. gamma than the Universal Trap. The addition of an insecticide to the Universal Trap marginally increased trap catches. In the Argentinian trials, the homemade bucket and the sleeve traps outperformed all sticky traps in most situations regardless of crop environment and attractant type. The homemade bucket and the funnel sleeve traps are also considerably cheaper than the other trap designs. Of the sticky traps the LepTrap caught more noctuids than the wing and delta traps. The results suggest that the bucket trap and the sleeve trap have a much greater maximum capacity and possibly a greater retention efficiency for noctuid moths compared to the sticky traps
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Commercial adoption of pheromones as a component in ICM of rice in Bangladesh
Bangladesh has been enormously successful in increasing its rice production in an effort to attain self-sufficiency. This has been largely achieved through an increase in acreage of the Boro crop (high-yielding, irrigated, post-rainyseason rice), with the BRRI introducing a range of high-yielding varieties to replace the more traditional deep-water varieties. However, insecticide use
is also increasing, at the expense of both farmers and the environment. To assist local institutions and companies to work with farmers to reduce insecticide use and promote integrated crop management (ICM), this project
aimed to adapt existing pheromone-based control methods (specifically for rice yellow stem borer) to local conditions, and incorporate them into the
ICM programme promoted by Syngenta Bangladesh Ltd through its farmer
field school programm
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Two-dimensional pixel array image sensor for protein crystallography
A 2D pixel array image sensor module has been designed for time resolved Protein Crystallography. This smart pixels detector significantly enhances time resolved Laue Protein crystallography by two to three orders of magnitude compared to existing sensors like films or phosphor screens coupled to CCDs. The resolution in time and dynamic range of this type of detector will allow one to study the evolution of structural changes that occur within the protein as a function of time. This detector will also considerably accelerate data collection in static Laue or monochromatic crystallography and make better use of the intense beam delivered by synchrotron light sources. The event driven pixel array detectors, based on the column Architecture, can provide multiparameter information (energy discrimination, time), with sparse and frameless readout without significant dead time. The prototype module consists of a 16x16 pixel diode array bump-bonded to the integrated circuit. The detection area is 150x150 square microns
Hemodynamic Effects of Entry and Exit Tear Size in Aortic Dissection Evaluated with In Vitro Magnetic Resonance Imaging and Fluid-Structure Interaction Simulation
Understanding the complex interplay between morphologic and hemodynamic
features in aortic dissection is critical for risk stratification and for the
development of individualized therapy. This work evaluates the effects of entry
and exit tear size on the hemodynamics in type B aortic dissection by comparing
fluid-structure interaction (FSI) simulations with in vitro 4D-flow magnetic
resonance imaging (MRI). A baseline patient-specific 3D-printed model and two
variants with modified tear size (smaller entry tear, smaller exit tear) were
embedded into a flow- and pressure-controlled setup to perform MRI as well as
12-point catheter-based pressure measurements. The same models defined the wall
and fluid domains for FSI simulations, for which boundary conditions were
matched with measured data. Results showed exceptionally well matched complex
flow patterns between 4D-flow MRI and FSI simulations. Compared to the baseline
model, false lumen flow volume decreased with either a smaller entry tear
(-17.8 and -18.5 %, for FSI simulation and 4D-flow MRI, respectively) or
smaller exit tear (-16.0 and -17.3 %). True to false lumen pressure difference
(initially 11.0 and 7.9 mmHg, for FSI simulation and catheter-based pressure
measurements, respectively) increased with a smaller entry tear (28.9 and 14.6
mmHg), and became negative with a smaller exit tear (-20.6 and -13.2 mmHg).
This work establishes quantitative and qualitative effects of entry or exit
tear size on hemodynamics in aortic dissection, with particularly notable
impact observed on FL pressurization. FSI simulations demonstrate acceptable
qualitative and quantitative agreement with flow imaging, supporting its
deployment in clinical studies.Comment: Judith Zimmermann and Kathrin B\"aumler contributed equall
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Solvent-Free Continuous Operations Using Small Footprint Reactors: A Key Approach for Process Intensification
A solvent-free approach to intensification of chemical processes is reported. This concept, in which reactions are carried out solvent-free, without the need for further downstream processing, was highlighted first with a full reduction of ethyl nicotinate to ethylpiperidine-3-carboxylate under continuous flow conditions. Using a small footprint reactor, a throughput of 26.4 g h–1 was achieved. Similarly, this approach was used for the telescoped two-step synthesis of 2-propyl phenol (productivity 120 g h–1) and 2-propyl cyclohexanone (productivity 30 g h–1), starting from the commercially available allyl phenol ether via Claisen rearrangement and subsequent reduction.We would like to thank Pfizer Worldwide Research & Development (CB), the EPSRC (RJM, SVL, Grant Codes EP/K009494/1, EP/M004120/1 and EP/K039520/1) and the Woolf Fisher Trust (DEF) for financial support.This is the final version of the article. It first appeared from the American Chemical Society via https://doi.org/10.1021/acssuschemeng.6b0028
Radiation Damage Effects on High-Purity Germanium Detectors
This research was sponsored by the National Science Foundation Grant NSF PHY-931478
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