Experimental Tests for Randomness of Quantum Decay Examined as a Markov Process [post-print]

The number of decays from four distinct nuclear disintegration processes were recorded over a long succession of counting intervals, converted into sequences of binary outcomes based on parity, and examined as a discrete two-state Markov process. The difference in single-step transition probabilities was found to be null to within an uncertainty of order 10−3, supporting the proposition that quantum particles decay at random unaffected by their past history

Search for correlated fluctuations in the B+ decay of Na-22

Claims for a “cosmogenic” force that correlates otherwise independent stochastic processes have been made for at least 10 years, based on visual inspection of histograms whose shapes were interpreted as suggestive of recurrent patterns. Building on our earlier work to test nuclear alpha, beta, and electron-capture decay processes for non-randomness, we searched for correlations in the time series of e+e- annihilations deriving from the decay of 22Na. Coincident gamma photons were counted within narrow time and energy windows over a period of 167 hours leading to a time series of more than 1 million events. Statistical tests for correlated fluctuations in the time series and its histograms were in all cases consistent with statistical control, giving no evidence of a “cosmogenic” force

Quantum test of the distributions of composite physical measurements [pre-print]

Probability distribution functions and lowest statistical moments of composite measurements representable as products and quotients of independent normal variates are derived, and tested by means of the α and β branching decays of 212Bi. The exact composite distribution functions are non-Gaussian and provide correct uncertainty estimates and confidence intervals in cases where standard error propagation relations are inaccurate. Although nuclear decay processes give rise to Poisson-distributed parent populations, the Gaussian-based composite distributions form nearly perfect envelopes to the discrete distributions of products and ratios of Poisson variates, even for relatively low counts. To our knowledge, this is the first reported experimental test of the statistics of composite measurements by a fundamental quantum process

Search for Patterns in Sequences of Single-Photon Polarization Measurements

Sequences of random binary numbers created from polarization measurements of single photons were subjected to a comprehensive runs analysis. Photon pairs from a spontaneous parametric downconversion source were detected in coincidence, with one photon acting as a trigger while the other was analyzed for horizontal or vertical polarization. The resulting sequences of polarization measurements were tested for runs of consecutive vertical or horizontal outcomes against a theory of nonoverlapping runs, without numerical unbiasing. The sequences produced no statistically significant discrepancies with the predicted numbers of runs, even with multiphoton events retained

Fragmentation of explosively metastable glass [post-print]

An unusual form of glass with bulbous head and thin tail, known as Rupert\u27s drops, can withstand high impact or pressure applied to the head, but explodes instantly into small particles when the tail is broken. The mechanism is not well understood. To examine this, we performed macro- and microstatistical analyses of a sample of 500 g of fragments of exploded Rupert\u27s drops to determine the mass and particle distributions and associated fractal dimensions. To our knowledge, this is the first such statistical study of the fragmentation of a metastable material with large internal energy. The resulting fractal dimensionD = 1.06 ± 0.09, derived from the scaling region of the mass and particle distribution functions approximated by power laws, differs from fractal dimensions (usually ≥2) previously reported for many brittle materials. The observed distribution functions place constraints on proposed mechanisms for the explosive disintegration of the drops and presumably other physical systems characterized by high compressive stress at the surface and tensile stress within the core

Faithful tissue-specific expression of the human chromosome 21-linked COL6A1 gene in BAC-transgenic mice

We created transgenic mice with a bacterial artificial chromosome (BAC) containing the human COL6A1 gene. In high-copy and low-copy transgenic lines, we found correct temporal and spatial expression of COL6A1 mRNA, paralleling the expression of the murine Col6a1 gene in a panel of nine adult and four fetal organs. The only exception was the fetal lung, in which the transgene was expressed poorly com- pared with the endogenous gene. Expression of COL6A1 mRNA from the transgene was copy number-dependent, and the increased gene dosage correlated with increased production of collagen VI alpha 1 in skin and heart, as indicated by Western blotting and immunohistochemistry. COL6A1 maps to Chromosome 21 and this gene has been a candi- date for contributing to cardiac defects and skin abnormalities in Down syndrome. The low-copy and high-copy COL6A1 transgenics were born and sur- vived in normal Mendelian proportions, without cardiac malformations or altered skin histology. These data indicate that the major promoter and enhancer sequences regulating COL6A1 expression are present in this 167-kb BAC clone. The lack of a strong cardiac or skin phenotype in the COL6A1 BAC-transgenic mice suggests that the increased expression of this gene does not, by itself, account for these phenotypes in Down syndrome

High-Velocity Line Forming Regions in the Type Ia Supernova 2009ig

We report measurements and analysis of high-velocity (> 20,000 km/s) and photospheric absorption features in a series of spectra of the Type Ia supernova (SN) 2009ig obtained between -14d and +13d with respect to the time of maximum B-band luminosity. We identify lines of Si II, Si III, S II, Ca II and Fe II that produce both high-velocity (HVF) and photospheric-velocity (PVF) absorption features. SN 2009ig is unusual for the large number of lines with detectable HVF in the spectra, but the light-curve parameters correspond to a slightly overluminous but unexceptional SN Ia (M_B = -19.46 mag and Delta_m15 (B) = 0.90 mag). Similarly, the Si II lambda_6355 velocity at the time of B-max is greater than "normal" for a SN Ia, but it is not extreme (v_Si = 13,400 km/s). The -14d and -13d spectra clearly resolve HVF from Si II lambda_6355 as separate absorptions from a detached line forming region. At these very early phases, detached HVF are prevalent in all lines. From -12d to -6d, HVF and PVF are detected simultaneously, and the two line forming regions maintain a constant separation of about 8,000 km/s. After -6d all absorption features are PVF. The observations of SN 2009ig provide a complete picture of the transition from HVF to PVF. Most SN Ia show evidence for HVF from multiple lines in spectra obtained before -10d, and we compare the spectra of SN 2009ig to observations of other SN. We show that each of the unusual line profiles for Si II lambda_6355 found in early-time spectra of SN Ia correlate to a specific phase in a common development sequence from HVF to PVF.Comment: 19 pages, 11figures, 4 tables, submitted to Ap

The Impact of Menthol Cigarettes on Smoking Initiation among Non-Smoking Young Females in Japan

Japan presents an excellent case-study of a nation with low female smoking rates and a negligible menthol market which changed after the cigarette market was opened to foreign competition. Internal tobacco industry documents demonstrate the intent of tobacco manufacturers to increase initiation among young females through development and marketing of menthol brands. Japanese menthol market share rose rapidly from less than 1% in 1980 to 20% in 2008. Menthol brand use was dominated by younger and female smokers, in contrast with non-menthol brands which were used primarily by male smokers. Nationally representative surveys confirm industry surveys of brand use and provide further evidence of the end results of the tobacco industry’s actions—increased female smoking in Japan. These findings suggest that female populations may be encouraged to initiate into smoking, particularly in developing nations or where female smoking rates remain low, if the tobacco industry can successfully tailor brands to them. The Japanese experience provides a warning to public health officials who wish to prevent smoking initiation among young females