COMSAT Laboratories' on-board baseband switch development

Work performed at COMSAT Laboratories to develop a prototype on-board baseband switch is summarized. The switch design is modular to accommodate different service types, and the architecture features a high-speed optical ring operating at 1 Gbit/s to route input (up-link) channels to output (down-link) channels. The switch is inherently a packet switch, but can process either circuit-switched or packet-switched traffic. If the traffic arrives at the satellite in a circuit-switched mode, the input processor packetizes it and passes it on to the switch. The main advantage of the packet approach lies in its simplified control structure. Details of the switch architecture and design, and the status of its implementation, are presented

Empirical developments in retraction

This study provides current data on key questions about retraction of scientific articles. Findings confirm that the rate of retractions remains low but is increasing. The most commonly cited reason for retraction was research error or inability to reproduce results; the rate from research misconduct is an underestimate, since some retractions necessitated by research misconduct were reported as being due to inability to reproduce. Retraction by parties other than authors is increasing, especially for research misconduct. Although retractions are on average occurring sooner after publication than in the past, citation analysis shows that they are not being recognised by subsequent users of the work. Findings suggest that editors and institutional officials are taking more responsibility for correcting the scientific record but that reasons published in the retraction notice are not always reliable. More aggressive means of notification to the scientific community appear to be necessary

Site-selective, catalytic, and diastereoselective sp3 C–H hydroxylation and alkoxylation of vicinally functionalized lactams

The C–H bond functionalization of sp3 carbon centres presents a significant challenge due to the inert nature of hydrocarbons as well as the need to selectively functionalize one of the numerous aliphatic C–H bonds embodied in organic molecules. Here, we describe catalytic, diastereoselective, and site-selective sp3 C–H hydroxylation/alkoxylation protocols featuring dihydroisoquinolones, γ-, and δ-lactams, which bear vicinal stereocenters. The hydroxylation strategy utilizes oxygen, a waste-free oxidant and affords attractive fragments for potential drug discovery. Fe-catalyzed dehydrative coupling of the resulting tertiary alcohols with simple primary alcohols has led to the construction of highly versatile unsymmetrical dialkyl ethers

Rebalancing commercial and public interests in prioritizing biomedical, social and environmental aspects of health through defining and managing conflicts of interest

Abstract Biomedical research is intended to benefit human beings and their health. Toward that end, scientific norms involve examining and criticizing the work of others and prioritizing questions that should be studied. Yet, in areas of health research where industry is active, it has often utilized well-honed strategies aimed at evading scientific standards and at dominating the research agenda, largely through its financial support and lack of transparency of its research practices. These tactics have now been documented to uniformly support industry products. Commercial entities are aided in this pursuit by public policy that has significantly embedded commercial interests and agendas into federal research funding and infrastructure. Therefore, to understand the resulting landscape and its effect on priority in health research agendas, traditional definitions of individual conflicts of interest (COI) and the less well developed institutional COI must be supplemented by a new construct of structural COI, largely operating as intellectual monopolies, in support of industry. These arrangements often result in financial and reputational resources that assure dominance of commercial priorities in research agendas, crowding out any other interests and ignoring justified returns to the public from investment of its tax dollars. There is no sustained attention to mechanisms by which public interests can be heard, normative issues raised, and then balanced with commercial interests which are transparently reported. Focus on research supporting approval of commercial products ignores social and environmental determinants of health. Commercial bias can invalidate regulatory research protections through obscuring valid risk–benefit ratios considered by IRBs

The representation of scientific research in the national curriculum and secondary school pupils’ perceptions of research, its function, usefulness and value to their lives

Young people’s views on what research is, how it is conducted and whether it is important, influences the decisions they make about their further studies and career choices. In this paper we report the analysis of questionnaire data with a particular focus on pupil perceptions of research in the sciences and of the scientific method. The questionnaire was a 25-item Likert Scale (1-5) distributed to seven collaborating schools. We received 2634 returns from pupils across key stages 3, 4 and 5. We also asked teachers to complete the questionnaire in order to explore how they thought their pupils would respond. We received 54 teacher responses. Statistically significant differences in the responses were identified through a chi-square test on SPSS. As what is being taught influences secondary pupil views on research we also consider how the term ‘research’ appears in the national curriculum for England and Wales and the three main English exam boards. The main theoretical construct that informs our analysis of the questionnaire data and the national curriculum is Angela Brew’s 4-tier descriptor of perceptions of research (domino, trading, layer, journey). We use this framework in order to map what, when and how research is presented to school pupils in England and Wales. We also use this framework in order to highlight and discuss certain pupil views that emerged from the questionnaire data and which indicate areas where curriculum and pedagogy intervention may be necessary: pupils seem less confident in their understanding of research as involving the identification of a research question; and, they often see research as a means to confirm one’s own opinion. They do however understand research as involving the generation of new knowledge and the collection of new data, such as interviews and questionnaires as well as laboratory work, field trips and library searches and they appear relatively confident in their statements about their ability to do research, their school experiences of research and the importance of research in their future career choice

Submillimetre observations of the two-component magnetic field in M82

We observed the starburst galaxy M82 in 850 µm polarized light with the POL-2 polarimeter on the James Clerk Maxwell Telescope (JCMT). We interpret our observed polarization geometry as tracing a two-component magnetic field: a poloidal component aligned with the galactic ‘superwind’, extending to a height ∼350 pc above and below the central bar; and a spiral-arm-aligned, or possibly toroidal, component in the plane of the galaxy, which dominates the 850 µm polarized light distribution at galactocentric radii ≳2 kpc. Comparison of our results with recent High-resolution Airborne Wideband Camera Plus (HAWC+) measurements of the field in the dust entrained by the M82 superwind suggests that the superwind breaks out from the central starburst at ∼350 pc above the plane of the galaxy

Long-term follow-up of patients with advanced ovarian cancer treated in randomised clinical trials.

The data from two prospective randomised phase III trials that were initiated by the West Midlands Ovarian Cancer Study Group (WMOCSG) in 1981 and 1986, recruiting 167 and 195 patients respectively, have been pooled and the survival patterns of the 362 patients treated for advanced epithelial ovarian cancer within clinical trials in the West Midlands over the 10 year period (1981-91) have been explored. All patients had histologically proven epithelial ovarian cancer and all had residual disease after primary surgery, with the majority having stage III/IV disease. The primary treatment for all patients was debulking surgery followed by platinum-based chemotherapy. Eligible patients were further randomised to undergo a second debulking operation. The main end point, survival, was assessed using Kaplan-Meier curves and the log-rank test. A Cox proportional hazards model identified performance status (P = 0.002), residual disease (P = 0.005) and albumin level (P = 0.04) as independent prognostic factors. A multivariate model to predict survival curves for patients with the best and worst prognoses was developed with predicted 5 year survival of 30% and 3% for those in the best and worst prognostic groups respectively. The identification of clinical interventions to improve outcome is an urgent matter since the prognosis for patients with advanced ovarian cancer remains poor

Self-aligned silicidation of surround gate vertical MOSFETs for low cost RF applications

We report for the first time a CMOS-compatible silicidation technology for surround-gate vertical MOSFETs. The technology uses a double spacer comprising a polysilicon spacer for the surround gate and a nitride spacer for silicidation and is successfully integrated with a Fillet Local OXidation (FILOX) process, which thereby delivers low overlap capacitance and high drive-current vertical devices. Silicided 80-nm vertical n-channel devices fabricated using 0.5-?m lithography are compared with nonsilicided devices. A source–drain (S/D) activation anneal of 30 s at 1100 ?C is shown to deliver a channel length of 80 nm, and the silicidation gives a 60% improvement in drive current in comparison with nonsilicided devices. The silicided devices exhibit a subthreshold slope (S) of 87 mV/dec and a drain-induced barrier lowering (DIBL) of 80 mV/V, compared with 86 mV/dec and 60 mV/V for nonsilicided devices. S-parameter measurements on the 80-nm vertical nMOS devices give an fT of 20 GHz, which is approximately two times higher than expected for comparable lateral MOSFETs fabricated using the same 0.5-?m lithography. Issues associated with silicidation down the pillar sidewall are investigated by reducing the activation anneal time to bring the silicided region closer to the p-n junction at the top of the pillar. In this situation, nonlinear transistor turn-on is observed in drain-on-top operation and dramatically degraded drive current in source-on-top operation. This behavior is interpreted using mixed-mode simulations, which show that a Schottky contact is formed around the perimeter of the pillar when the silicided contact penetrates too close to the top S/D junction down the side of the pillar