996 research outputs found
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Enhancement of latent fingerprints on fabric using the cyanoacrylate fuming method followed by infrared spectral mapping
A method has been developed for the visualization of latent fingerprints on fabrics, which is based upon cyanoacrylate (superglue) fuming followed by imaging using an infrared microscope. Results show that imaging on smooth, shiny fabrics such as polyester, silk, nylon and acetate of different colors and patterns can give an improvement over existing enhancement methods. Results for cotton and polycotton were less successful and it is thought this may be due a combination of the presence of the carbonyl functional group in these fabrics as well as their absorbency to fingerprint sweat. The carbonyl peak (1700 cm-1) provided the optimum spectroscopic feature to map and image a fingerprint. Comparisons between infrared mapping at a specific frequency range and principal component analysis showed that improved imaging was obtained with principal component analysis
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Enhancement of aged and denatured fingerprints using the cyanoacrylate fuming technique following dusting with amino acid-containing powders
We have carried out experiments to investigate the ageing of latent fingerprints deposited on black PVC over a period of 4-15 weeks. A thumbprint was used in each case and before deposition of the print the donor rubbed their thumb around their nose to add sebaceous deposits. We have studied the effect of heat, light and moisture and we find that moisture is the most significant factor in the degradation of the latent print. We have attempted to enhance these latent prints by dusting with valine powder or powders composed of valine mixed with gold or red fluorescent commercial fingerprint powders. In order to make a direct comparison between “treated” and “untreated” prints, the prints were cut in half with one half being “treated” and one not. Our studies show the best results being obtained when powders of valine and red fluorescent powders are applied prior to cyanoacrylate fuming
Primordial helium recombination III: Thomson scattering, isotope shifts, and cumulative results
Upcoming precision measurements of the temperature anisotropy of the cosmic
microwave background (CMB) at high multipoles will need to be complemented by a
more complete understanding of recombination, which determines the damping of
anisotropies on these scales. This is the third in a series of papers
describing an accurate theory of HeI and HeII recombination. Here we describe
the effect of Thomson scattering, the He isotope shift, the contribution of
rare decays, collisional processes, and peculiar motion. These effects are
found to be negligible: Thomson and He scattering modify the free electron
fraction at the level of several . The uncertainty in the
rate is significant, and for conservative estimates gives
uncertainties in of order . We describe several convergence
tests for the atomic level code and its inputs, derive an overall
error budget, and relate shifts in to the changes in , which
are at the level of 0.5% at . Finally, we summarize the main
corrections developed thus far. The remaining uncertainty from known effects is
in .Comment: 19 pages, 15 figures, to be submitted to PR
Amateur versus professional: Does the recovery of forensic evidence differ depending on who assesses the crime scene?
Volume crime offences such as domestic burglary are commonly assessed for forensic opportunities by the first attending officer present at the scene. Conversely, less serious volume crime offences such as thefts from motor vehicles are very frequent and are routinely assessed for forensic opportunities by the victim talking to the police over the telephone. It is not clear whether this difference in attendance policy leads to differences in the types and quantity of forensic material recovered. The current study explored whether there was a benefit to evidence recovery for attended as opposed to non-attended assessments. Five hundred thefts from motor vehicles offences recorded by Northamptonshire Police (UK) between 14 January 2010 and 28 February 2011 were analysed; 250 were attended forensic assessments and 250 were non-attended assessments. Significant differences were found between the two scenarios, with attended assessments more likely to yield DNA, property and trace substance material. Conversely, fingerprints were more likely to be recovered at non-attended assessments. Despite the fruitful findings of the current study, future research would benefit from establishing the methods used by the first attending officer and forensic investigator when assessing and gathering evidence. Similarly, it is unclear whether these differences in forensic material are reflected in the identification of an offender and subsequently in the solving of the crime
Prenatal development is linked to bronchial reactivity: epidemiological and animal model evidence
Chronic cardiorespiratory disease is associated with low birthweight suggesting the importance of the developmental environment. Prenatal factors affecting fetal growth are believed important, but the underlying mechanisms are unknown. The influence of developmental programming on bronchial hyperreactivity is investigated in an animal model and evidence for comparable associations is sought in humans. Pregnant Wistar rats were fed either control or protein-restricted diets throughout pregnancy. Bronchoconstrictor responses were recorded from offspring bronchial segments. Morphometric analysis of paraffin-embedded lung sections was conducted. In a human mother-child cohort ultrasound measurements of fetal growth were related to bronchial hyperreactivity, measured at age six years using methacholine. Protein-restricted rats' offspring demonstrated greater bronchoconstriction than controls. Airway structure was not altered. Children with lesser abdominal circumference growth during 11-19 weeks' gestation had greater bronchial hyperreactivity than those with more rapid abdominal growth. Imbalanced maternal nutrition during pregnancy results in offspring bronchial hyperreactivity. Prenatal environmental influences might play a comparable role in humans
Confirmation of SBS 1150+599A As An Extremely Metal-Poor Planetary Nebula
SBS 1150+599A is a blue stellar object at high galactic latitude discovered
in the Second Byurakan Survey. New high-resolution images of SBS 1150+599A are
presented, demonstrating that it is very likely to be an old planetary nebula
in the galactic halo, as suggested by Tovmassian et al (2001). An H-alpha image
taken with the WIYN 3.5-m telescope and its "tip/tilt" module reveals the
diameter of the nebula to be 9.2", comparable to that estimated from spectra by
Tovmassian et al. Lower limits to the central star temperature were derived
using the Zanstra hydrogen and helium methods to determine that the star's
effective temperature must be > 68,000K and that the nebula is optically thin.
New spectra from the MMT and FLWO telescopes are presented, revealing the
presence of strong [Ne V] lambda 3425, indicating that the central star
temperature must be > 100,000K. With the revised diameter, new central star
temperature, and an improved central star luminosity, we can constrain
photoionization models for the nebula significantly better than before. Because
the emission-line data set is sparse, the models are still not conclusive.
Nevertheless, we confirm that this nebula is an extremely metal-poor planetary
nebula, having a value for O/H that is less than 1/100 solar, and possibly as
low as 1/500 solar.Comment: 19 pages, 6 figures. Accepted for publication in the Astronomical
Journa
Evidence for dark energy from the cosmic microwave background alone using the Atacama Cosmology Telescope lensing measurements
For the first time, measurements of the cosmic microwave background radiation
(CMB) alone favor cosmologies with dark energy over models without dark
energy at a 3.2-sigma level. We demonstrate this by combining the CMB lensing
deflection power spectrum from the Atacama Cosmology Telescope with temperature
and polarization power spectra from the Wilkinson Microwave Anisotropy Probe.
The lensing data break the geometric degeneracy of different cosmological
models with similar CMB temperature power spectra. Our CMB-only measurement of
the dark energy density confirms other measurements from
supernovae, galaxy clusters and baryon acoustic oscillations, and demonstrates
the power of CMB lensing as a new cosmological tool.Comment: 4 pages, 3 figures; replaced with version accepted by Physical Review
Letters, added sentence on models with non-standard primordial power spectr
Adipose‐Derived Stem Cells Induce Angiogenesis via Microvesicle Transport of miRNA‐31
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135340/1/sct3201654440.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/135340/2/Supplemental_Information.pd
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