Experimental observation of dissociative electron attachment to S2O and S2O2 with a new spectrometer for unstable molecules

A new spectrometer, electron radical interaction chamber, has been developed to study dissociative electron attachment to unstable molecules such as free radicals. It includes a trochoidal electron monochromator and a time-of-flight mass spectrometer. Radicals are generated with a microwave discharge at 2.45 GHz. Preliminary data are presented for radicals formed when a mixture of helium and sulphur dioxide was passed through the microwave discharge. Several new resonances are observed with the discharge on. Resonances at 0 eV (S-), 0.8, 1.2, 3.0 eV (SO-) and 3.7 eV (SO- and S2O-) are assigned to the radical S2O2 and a resonance at 1.6 eV (S-) is assigned to S2O. No new resonances have been assigned to SO, which was also generated in the microwave discharge.

Dissociative electron attachment to HCCCN

Dissociative electron attachment to cyanoacetylene (propiolonitrile) HCCCN has been observed in the electron energy range 0-12 eV. Negative ions are formed in two main bands with maxima at similar to 1.6 eV (CCCN-) and similar to 5.3 eV (CCCN-, CN-, HCC- and CC-). There are also weaker resonances which lead to dissociative electron attachment to form CN-, HCC- and CC- with a maximum intensity at similar to 8.1 eV and CCCN-, CN- and CC- at similar to 11.2 eV. A trace of CCN- is observed at similar to 9.1 eV. The positions of the main dissociative attachment bands observed are close to positions of pi* resonances recently calculated by Sommerfeld and Knecht. Calculations have also been performed in this work, which confirm the position of the p* orbitals. The electron affinity of the CCCN radical is determined as 4.59 +/- 0.25 eV from the threshold for CCCN- formation at 1.32 +/- 0.15 eV. Dissociative electron attachment to this molecule will act as a source of negative ions in extraterrestrial environments where electrons are present with more than 1.3 eV energy.

A k-round Elimination Contention Scheme for WLANs

currently in press. This is the first published attempt to engineer QoS into a contention-based MAC layer protocol. The work was based on a cross-layer approach to providing programmability into wireless LANs. The work arose from an EPSRC grant in the "programmable networks" call, with Philips / STM research in Italy (Dr Melpignano). Subsequent follow-on includes the formation of a spin-out company (TOM) based on the idea.

Attachment Style in Adults who Failed to Thrive as Children: Outcomes of a 20 Year Follow-up Study of Factors Influencing Maintenance or Change in Attachment Style

A group of children identified as non-organic failure-to-thrive between 1977 and 1980 were investigated, assessed and provided with social work intervention and treatment. Those children and their families have been followed up for the last 20 years. The current paper examines the stability of an internal working model in a sample of individuals who had failed to thrive as children, by comparing each individual's adult attachment style with their childhood attachment to their mother. In this sample, several cases showed changes from insecure to secure attachment styles. Possible reasons are discussed for positive and negative changes, as well as cases when there was no change in attachment style. These include the effectiveness of intervention in addition to changes in life circumstances. The findings suggest that when appropriate support and intervention is provided, or when different circumstances or relationships are experienced, internal working models can change.

Universal power quality manager with a new control scheme

A new universal power quality manager is proposed. The proposal treats a number of power quality problems simultaneously. The universal manager comprises a combined series and shunt three-phase PWM controlled converters sharing a common DC link. A control scheme based on fuzzy logic is introduced and the general features of the design and operation processes are outlined. The performance of two configurations of the proposed power quality manager are compared in terms of a recently formulated unified power quality index. The validity and integrity of the proposed system is proved through computer simulated experiments

Maternal appraisals of risk, coping and prenatal attachment among women hospitalised with pregnancy complications

One goal of pregnancy is the development of maternal emotional attachment to
the unborn baby, and this attachment has been shown to be related to later
relationships and development. There are many factors which may hinder the
development of prenatal attachment, including the presence of complications,
hospitalisation, and anxiety. However, women’s appraisals of risk may not be
congruent with medical assessments of risk. The current study sought to model
the relationships between risk (maternal perceptions and medical ratings), coping, psychological well-being, and maternal–foetal attachment among 87 women hospitalised for pregnancy-related complications. Analysis indicated that positive appraisal as a coping strategy mediates the relationship between maternal appraisals of risk and maternal–foetal attachment, and that medical ratings of risk were not predictive of maternal–foetal attachment. Awareness of the potential incongruence between patients’ and health professionals’ perceptions of risk is important within the clinical environment. The potential benefits of promoting positive appraisal in high-risk pregnancy merit further research.