Environmental Perturbations that Cause Structural Changes in the SNARE Protein SNAP-25

Digitalitzat per Artypla

Changes in Gene Sequence that Cause Discordances Involving Disease in Monozygotic Twins

Identical twins or, monozygotic twins, occur when the egg in a mother is fertilized, but one zygote divides into two separate embryos. Monozygotic twins are considered to be genetically identical, but most twins often display discordances, some involving diseases or disorders. Some of these differences are due to environmental factors. For example, one twin may have diabetes due to diet. Recent literature has shown that some differences in monozygotic twins may be due to changes in gene sequence, as opposed to random, environmental or epigenetic factors. Identical twins from pedigrees with familial disease often show discordances. When looking at schizophrenia specifically, the discordance rate is about 50%. This poster will review literature about specific de novo variants, duplication, overlaps, and even a rare deletion in an affected twin, which provides evidence a specific mutation contributes to a particular disorder. These findings in monozygotic twins will further research that provides information on how to treat or prevent disorders that are caused by genetic changes

Caught in the act: Measuring the changes in the corona that cause the extreme variability of 1H 0707-495

The X-ray spectra of the narrow line Seyfert 1 galaxy, 1H 0707-495, obtained with XMM-Newton, from time periods of varying X-ray luminosity are analysed in the context of understanding the changes to the X-ray emitting corona that lead to the extreme variability seen in the X-ray emission from active galactic nuclei (AGN). The emissivity profile of the accretion disc, illuminated by the X-ray emitting corona, along with previous measurements of reverberation time lags are used to infer the spatial extent of the X-ray source. By fitting a twice-broken power law emissivity profile to the relativistically-broadened iron K fluorescence line, it is inferred that the X-ray emitting corona expands radially, over the plane of the accretion disc, by 25 to 30 per cent as the luminosity increases, contracting again as the luminosity decreases, while increases in the measured reverberation lag as the luminosity increases would require also variation in the vertical extent of the source above the disc. The spectrum of the X-ray continuum is found to soften as the total X-ray luminosity increases and we explore the variation in reflected flux as a function of directly-observed continuum flux. These three observations combined with simple, first-principles models constructed from ray tracing simulations of extended coron self-consistently portray an expanding corona whose average energy density decreases, but with a greater number of scattering particles as the luminosity of this extreme object increases.Comment: 12 pages, 4 figures. Accepted for publication in MNRA

Composite Structures that Change Shape in Response to Changes in Temperature

The present invention is a composite structure that changes shape as temperatures change. The composite structure utilizes a flexible substrate. The flexible substrate is static and does not change shape by itself in response to changes in temperature. A supports structure is affixed to the flexible substrate. The support structure is made from bi-layer films that change shape in response to changes in temperature. The support structures are formed into complex shapes that are smaller than the flexible substrates they support. As a result, when the support structure are affixed to the flexible substrates, the support structures cause the flexible substrates to buckle, bend and twist as the support structures change shape with temperature. The support structures can be designed so as to cause the specific changes in the flexible substrate to as to mimic the natural blooming movements of a flower petal or leaf.Published versio

Electrolyte Abnormalities on ECG

The authors review the characteristic changes that hypercalcemia, hyperkalemia, hypokalemia, and other serum electrolyte abnormalities can cause on an ECG

Oil prices and stock markets: what drives what in the Gulf Corporation Council countries?

In the empirical literature, only few studies have focused on the relationship between oil prices and stock markets in net oil-importing countries. In net oil-exporting countries this relationship has not been widely researched. This paper implements the panel-data approach of Kónya (2006), which is based on SUR systems and Wald tests with country-specific bootstrap critical values to study the sensitivity of stock markets to oil prices in GCC (Gulf Corporation Council) countries. Using two different (weekly and monthly) datasets covering respectively the periods from 7 June 2005 to 21 October 2008, and from January 1996 to December 2007, we show strong statistical evidence that the causal relationship is consistently bi-directional for Saudi Arabia. Stock market price changes in the other GCC member countries do not Granger cause oil price changes, whereas oil price shocks Granger cause stock price changes. Therefore, investors in GCC stock markets should look at the changes in oil prices, whereas investors in oil markets should look at changes in the Saudi stock market.http://deepblue.lib.umich.edu/bitstream/2027.42/64354/1/wp960.pd

Low phase noise oscillator using two parallel connected amplifiers

A high frequency oscillator is provided by connecting two amplifier circuits in parallel where each amplifier circuit provides the other amplifier circuit with the conditions necessary for oscillation. The inherent noise present in both amplifier circuits causes the quiescent current, and in turn, the generated frequency, to change. The changes in quiescent current cause the transconductance and the load impedance of each amplifier circuit to vary, and this in turn results in opposing changes in the input susceptance of each amplifier circuit. Because the changes in input susceptance oppose each other, the changes in quiescent current also oppose each other. The net result is that frequency stability is enhanced

Determinants of immediate price impacts at the trade level in an emerging order-driven market

The common wisdom argues that, in general, large trades cause large price changes, while small trades cause small price changes. However, for extremely large price changes, the trade size and news play a minor role, while the liquidity (especially price gaps on the limit order book) is a more influencing factor. Hence, there might be other influencing factors of immediate price impacts of trades. In this paper, through mechanical analysis of price variations before and after a trade of arbitrary size, we identify that the trade size, the bid-ask spread, the price gaps and the outstanding volumes at the bid and ask sides of the limit order book have impacts on the changes of prices. We propose two regression models to investigate the influences of these microscopic factors on the price impact of buyer-initiated partially filled trades, seller-initiated partially filled trades, buyer-initiated filled trades, and seller-initiated filled trades. We find that they have quantitatively similar explanation powers and these factors can account for up to 44% of the price impacts. Large trade sizes, wide bid-ask spreads, high liquidity at the same side and low liquidity at the opposite side will cause a large price impact. We also find that the liquidity at the opposite side has a more influencing impact than the liquidity at the same side. Our results shed new lights on the determinants of immediate price impacts.Comment: 21 IOP tex pages including 5 figures and 5 tables. Accepted for publication in New Journal of Physic

An XRD Study of Chemical Self-Discharge in Delithiated Cobalt Oxide

Changes in samples of Li1–xCoO2 were measured by X-ray diffractometry (XRD) after thermal aging treatments that cause capacity losses in electrochemical cells. Changes in lattice parameters were used to identify lithium re-intercalation into Li1–xCoO2 when it was aged in the presence of LiClO4, LiPF6, and LiAsF6 in propylene carbonate (PC). Li+ re-intercalation could account for the reversible capacity loss. Thermal aging at 75°C in pure PC or pure argon gas resulted in other changes that are attributed to the formation of spinel phase. The rate of the lithium re-intercalation increases in the following sequence: LiPF6<LiClO4<LiAsF6