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The impact of spikes in handgun acquisitions on firearm-related harms.
BackgroundResearch has documented sharp and short-lived increases in firearm acquisitions immediately following high-profile mass shootings and specific elections, increasing exposure to firearms at the community level. We exploit cross-city variation in the estimated number of excess handgun acquisitions in California following the 2012 presidential election and the Sandy Hook school shooting 5 weeks later to assess whether the additional handguns were associated with increases in the rate of firearm-related harms at the city level.MethodsWe use a two-stage modeling approach. First, we estimate excess handguns as the difference between actual handgun acquisitions, as recorded in California's Dealer Record of Sales, and expected acquisitions, as predicted by a seasonal autoregressive integrated moving-average (SARIMA) time series model. We use Poisson regression models to estimate the effect of city-level excess handgun purchasing on city-level changes in rates of firearm mortality and injury.ResultsWe estimate there were 36,142 excess handguns acquired in California in the 11 weeks following the election (95% prediction interval: 22,780 to 49,505); the Sandy Hook shooting occurred in week 6. We find city-level purchasing spikes were associated with higher rates of firearm injury in the 52 weeks post-election: a relative rate of 1.044 firearm injuries for each excess handgun per 1,000 people (95% CI: 1.000 to 1.089). This amounts to approximately 290 (95% CI: 0 to 616) additional firearm injuries (roughly a 4% increase) in California over the year. We do not detect statistically significant associations for shorter time windows or for firearm mortality.ConclusionThis study provides evidence for an association between excess handgun acquisitions following high-profile events and firearm injury at the community level. This suggests that even marginal increases in handgun prevalence may be impactful
On the basic mechanism of Pixelized Photon Detectors
A Pixelized Photon Detector (PPD) is a generic name for the semiconductor
devices operated in the Geiger-mode, such as Silicon PhotoMultiplier and
Multi-Pixel Photon Counter, which has high photon counting capability. While
the internal mechanisms of the PPD have been intensively studied in recent
years, the existing models do not include the avalanche process. We have
simulated the multiplication and quenching of the avalanche process and have
succeeded in reproducing the output waveform of the PPD. Furthermore our model
predicts the existence of dead-time in the PPD which has never been numerically
predicted. For serching the dead-time, we also have developed waveform analysis
method using deconvolution which has the potential to distinguish neibouring
pulses precisely. In this paper, we discuss our improved model and waveform
analysis method.Comment: 4pages, 5figures, To appear in the proceedings of 5th International
Conference on New Developments in Photodetection (NDIP08), Aix-les-Bains,
France, 15-20 Jun 200
Possibility of Macroscopic resonant Tunneling near the Superconductor- Insulator Transition in YBaCuO Thin Films
Experimental results of I-V characteristics near the superconductor-insulator
transition observed for disorder-tuned YBaCuO thinfilms are presented. The I-V
characteristics exibit new quasiperiodic structures as a function of the
current. The current interval, the number of the dI/dV peaks, and the magnetic
field dependence of the peaks are consistent with the theoretical predictions
of the resonant tunneling of a phase particle ina tilted-cosine potential for
asingle Josephson junction with small capacitance.Comment: 7 pages, 4 figures, in press (Europhys. Lett.
Morphological Effects of Glycosaminoglycans on Calcium Oxalate Monohydrate Crystals
The effects of individual glycosaminoglycan (GAG) species on calcium oxalate monohydrate (COM) crystal growth were studied in vitro by the observation of crystal morphology grown in a supersaturated calcium oxalate solution in the presence of GAGs using optical and scanning electron microscopes. GAGs affected the morphology of COM crystals differently depending on the species. The growth rates of the crystals formed in the presence of chondroitin-6-sulfate (ChS-C) were higher in length and lower in width and thickness than those of control crystals. The incorporation of dermatan sulfate or heparin into the crystals formed in the presence of these GAGs was revealed by X-ray microanalysis, whereas ChS-C was not detected in the crystals grown with it. The experiment using dicarboxylates, as a simple model of GAG molecules, showed that a distance between the side groups was important for their morphological effects. These findings suggested that the different effects of GAGs on the crystal morphology resulted from the differences in their interaction modes with COM crystal faces, that is, the differences in their binding behavior, their inhibition modes of crystal growth, and other roles played after binding to the crystals
The first success of glass eel production in the world: basic biology on fish reproduction advances new applied technology in aquaculture
The eel has long been esteemed as an important food fish in the world, especially in Japan, and has been used as an experimental fish for many fields of fish physiology. However, the decreases in eel resources have been a serious concern in recent years. The catches of glass eels as seedlings for aquaculture have shown a long-term decrease in both Europe and East Asia. To increase eel resources, the development of techniques for artificial induction of maturation and spawning and rearing their larvae have been eagerly desired. Recent progress of reproductive physiology of fish, especially mechanisms of oocyte maturation and ovulation in female and of spermatozoa maturation in male, facilitate to establish techniques for hormonal induction of maturation and spawning in sexually immature eels. With persistent effort to development of rearing techniques of larvae, we have first succeeded to produce glass eel. These applied techniques are may contribute to understand the basic reproductive physiology of the eel
Energetic perspective on emergent inductance exhibited by magnetic textures in the pinned regime
Spatially varying magnetic textures can exhibit electric-current-induced
dynamics as a result of the spin-transfer torque effect. When such a magnetic
system is electrically driven, an electric field is generated, which is called
the emergent electric field. In particular, when magnetic-texture dynamics are
induced under the application of an AC electric current, the emergent electric
field also appears in an AC manner, notably, with an out-of-phase time profile,
thus exhibiting inductor behaviour, often called an emergent inductor. Here we
show that the emergent inductance exhibited by magnetic textures in the pinned
regime can be explained in terms of the current-induced energy stored in the
magnetic system. We numerically find that the inductance values defined from
the emergent electric field and the current-induced magnetization-distortion
energy, respectively, are in quantitative agreement in the so-called adiabatic
limit. Our findings indicate that emergent inductors retain the basic concept
of conventional inductors; that is, the energy is stored under the application
of electric current
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