ABSOLUTE DOUBLY DIFFERENTIAL CROSS-SECTIONS FOR ELECTRON-EMISSION IN COLLISIONS OF 3.5-MEV/U FE(17+) AND FE(22+) IONS WITH HE AND AR GAS TARGETS

Absolute doubly differential cross sections have been measured as a function of electron energy and angle of observation for electron emission in collisions of 3.5-MeV/u Fe17+ and Fe22+ ions with He and Ar gas targets under single-collision conditions. The measured electron emission cross sections are compared to theoretical and scaled cross sections based on the Born approximation. The results using intermediate-mass ions are discussed with reference to previously reported cross sections from collisions with highly charged lighter- and heavier-ion species at MeV/u projectile energies. The continuum-distorted-wave-eikonal-initial-state approximation shows good agreement with experiments except in the

Differential Associations of Job Control Components With Mortality: A Cohort Study, 1986-2005

Inconsistent evidence of the hypothesized favorable effects of high job control on health may have resulted from a failure to treat job control as a multifactor concept. The authors studied whether the 2 components of job control, decision authority and skill discretion, were differentially associated with cause-specific mortality in 13,510 Finnish forest company employees with no history of severe illness. Surveys on work characteristics were carried out in 1986 and 1996, and the respondents were followed up until the end of 2005 by use of the Statistics Finland National Death Registry. During a mean follow-up of 15.5 years, 981 participants died. In the analyses adjusted for confounders, employees with high and intermediate levels of skill discretion had a lower all-cause mortality risk than those with low skill discretion, with hazard ratios of 0.84 (95% confidence interval (CI): 0.69, 1.02) and 0.81 (95% CI: 0.69, 0.96), respectively. In contrast, high decision authority was associated with elevated risks of all-cause, cardiovascular, and alcohol-related mortality, with hazard ratios of 1.28 (95% CI: 1.06, 1.54), 1.49 (95% CI: 1.11, 2.02), and 2.03 (95% CI: 1.03, 4.00), respectively. The results suggest that job control is not an unequivocal concept in relation to mortality; decision authority and skill discretion show different and to some extent opposite associations.

Differential TERT promoter methylation and response to 5-aza-2'-deoxycytidine in acute myeloid leukemia cell lines:TERT expression, telomerase activity, telomere length, and cell death

The catalytic subunit of human telomerase (TERT) is highly expressed in cancer cells, and correlates with complex cytogenetics and disease severity in acute myeloid leukemia (AML). The TERT promoter is situated within a large CpG island, suggesting that expression is methylation-sensitive. Studies suggest a correlation between hypermethylation and TERT overexpression. We investigated the relationship between TERT promoter methylation and expression and telomerase activity in human leukemia and lymphoma cell lines. DAC-induced demethylation and cell death were observed in all three cell lines, as well as telomere shortening in HL-60 cells. DAC treatment reduced TERT expression and telomerase activity in OCI/AML3 and HL-60 cells, but not in U937 cells. Control U937 cells expressed lower levels of TERT mRNA, carried a highly methylated TERT core promoter, and proved more resistant to DAC-induced repression of TERT expression and cell death. AML patients had significantly lower methylation levels at several CpGs than "well elderly" individuals. This study, the first to investigate the relationship between TERT methylation and telomerase activity in leukemia cells, demonstrated a differential methylation pattern and response to DAC in three AML cell lines. We suggest that, although DAC treatment reduces TERT expression and telomerase activity, this is unlikely to occur via direct demethylation of the TERT promoter. However, further investigations on the regions spanning CpGs 7-12 and 14-16 may reveal valuable information regarding transcriptional regulation of TERT.

A test of the extended intergroup contact hypothesis: The mediating role of intergroup anxiety, perceived ingroup and outgroup norms, and inclusion of the outgroup in the self

S. C. Wright, A. Aron, T. McLaughlin-Volpe, and S. A. Ropp (1997) proposed that the benefits associated with cross-group friendship might also stem from vicarious experiences of friendship. Extended contact was proposed to reduce prejudice by reducing intergroup anxiety, by generating perceptions of positive ingroup and outgroup norms regarding the other group, and through inclusion of the outgroup in the self. This article documents the first test of Wright et al.'s model, which used structural equation modeling among two independent samples in the context of South Asian-White relations in the United Kingdom. Supporting the model, all four variables mediated the relationship between extended contact and outgroup attitude, controlling for the effect of direct contact. A number of alternative models were ruled out, indicating that the four mediators operate concurrently rather than predicting one another.

A need to belong?: The prevalence of experiences of belonging and exclusion in school among minority ethnic children living in the 'White hinterlands'

Based on a survey of 711 children in Northern Ireland, this paper explores a range of aspects of experiences of belonging and exclusion in relation to school among three main minority ethnic groups: Irish Traveller, Chinese/Asian and European Migrant children. The study examines variations between each group and how they compare to the White settled population. The findings indicate that all three groups experience lower levels of belonging and higher levels of exclusion compared to their White, settled Northern Irish peers. The experiences of Irish Traveller children were the most negative. The article adds to the dearth of data on minority ethnic children living in mainly white regions in the UK and Ireland. It argues for the need to move beyond achievement gaps in assessing minority ethnic children’s differential experiences in education and highlights the potential of belongingness as a concept for the further study of differential patterns of need and processes of inclusion.

Phytochelatins are involved in differential arsenate tolerance in Holcus lanatus

Arsenate tolerance is conferred by suppression of the high-affinity phosphate/arsenate uptake system, which greatly reduces arsenate influx in a number of higher plant species. Despite this suppressed uptake, arsenate-tolerant plants can still accumulate high levels of As over their lifetime, suggesting that constitutive detoxification mechanisms may be required. Phytochelatins are thiol-rich peptides, whose production is induced by a range of metals and metalloids including arsenate. This study provides evidence for the role of phytochelatins in the detoxification of arsenate in arsenate-tolerant Holcus lanatus. Elevated levels of phytochelatin were measured in plants with a range of tolerance to arsenate at equivalent levels of arsenate stress, measured as inhibition of root growth. The results suggest that arsenate tolerance in H. lanatus requires both adaptive suppression of the high-affinity phosphate uptake system and constitutive phytochelatin production.

Differential power analysis resistance of Camellia and countermeasure strategy on FPGAs

Security devices are vulnerable to Differential Power Analysis (DPA) that reveals the key by monitoring the power consumption of the circuits. In this paper, we present the first DPA attack against an FPGA implementation of the Camellia encryption algorithm with all key sizes and evaluate the DPA resistance of the algorithm. The Camellia cryptographic algorithm involves several different key-dependent intermediate operations including S-Box operations. In previous research, it was believed that the Camellia is stronger than AES due to the additional Whitening phase protecting the S-Box operation. However, we propose an attack that bypasses the Whitening phase and targets the S-Box. In this paper, we also discuss a lowcost countermeasure strategy to protect the Pre-whitening / Post-whitening and FL function of Camellia using Dual-rail Precharged Logic and to protect against attacks of the S-Box using Random Delay Insertion. © 2009 IEEE.

A 76-84 GHz SiGe power amplifier array employing low-loss four-way differential combining transformer

This paper presents holistic design of a novel four-way differential power-combining transformer for use in millimeter-wave power-amplifier (PA). The combiner with an inner radius of 25 µm exhibits a record low insertion loss of 1.25 dB at 83.5 GHz. It is designed to simultaneously act as a balanced-to-unbalanced converter, removing the need for additional BALUNs typically required in differential circuits. A complete circuit comprised of a power splitter, two-stage differential cascode PA array, a power combiner as well as input and output matching elements was designed and realized in SiGe technology with f/f 170/250 GHz. Measured small-signal gain of at least 16.8 dB was obtained from 76.4 to 85.3 GHz with a peak 19.5 dB at 83 GHz. The prototype delivered 12.5 dBm output referred 1 dB compression point and 14 dBm saturated output power when operated from a 3.2 V dc supply voltage at 78 GHz.

Ultrafast low-loss 42-70 GHz differential SPDT switch in 0.35 μm SiGe technology

This paper presents an ultrafast wideband low-loss single-pole double-throw (SPDT) differential switch in 0.35 µ m SiGe bipolar technology. The proposed topology adopting current-steering technique results in a total measured switching time of 75 ps , which suggests a maximum switching rate of 13 Gb/s, the fastest ever reported at V-band. In addition, the switch exhibits an insertion loss lower than 1.25 dB and an isolation higher than 18 dB from 42 GHz to 70 GHz. © 2006 IEEE.