D-LQF: An efficient distributed scheduling algorithm for input-queued switches

Due to the massive use of parallel and distributed operations of inputs and outputs, iterative scheduling algorithms are attractive in finding a maximal size matching for an input-queued switch. For constructing a large high-speed switch, a distributed multi-chip implementation of an iterative scheduling algorithm should be followed. Since different chips may locate on different switch linecards and linecards can be separated by tens of meters, the propagation delay between chips/linecards is non-negligible. This calls for a pipelined implementation of a single-iteration scheduling algorithm. In this paper, an efficient, pipelined single-iteration algorithm called Distributed Longest Queue First (D-LQF) is proposed. In D-LQF, exhaustive service policy is adopted for reusing the matched input-output pairs in the previous time slot. To avoid incorrectly granting an empty VOQ from transmission (caused by inter-chip latency), each output keeps track of the lengths of all VOQs destined to it. As compared with other single-iteration scheduling algorithms, extensive simulation results show that D-LQF provides the best delay-throughput performance. © 2011 IEEE.published_or_final_versionThe 2011 IEEE International Conference on Communications (ICC 2011), Kyoto, Japan, 5-9 June 2011. In Proceedings of the IEEE ICC, 2011, p. 1-

Achieving 100% throughput for multicast traffic in input-queued switches

A general approach of designing input-queued multicast switch is to employ multicast switch fabric, where packets can be replicated inside the switch fabric. As compared with unicast switch fabric, the achievable traffic rate region of a switch can be increased, but it is still less than the admissible traffic rate region. In other words, achieving 100% throughput for any admissible multicast traffic pattern is not possible. In this paper, we first revisit the fundamental problems faced by input-queued switch in supporting multicast traffic. We then argue that multicast switch fabric is not necessary if a load-balanced approach is followed. Accordingly, an existing load-balanced two-stage switch architecture [12], consisting of unicast switch fabrics, can be adopted to provide 100% throughput for any admissible multicast traffic pattern. Since the two-stage switch requires no speedup in both switch fabric and packet buffers, we consider it a two-stage input-queued switch. It can be seen that its implementation complexity is much lower than conventional (single-stage) input-queued multicast switches. As compared with the work in [12], our approach is more systematic and we propose a more effective load balancing mechanism. © 2011 IEEE.link_to_subscribed_fulltextProceedings of the IEEE Global Telecommunications Conference (GLOBECOM 2011), Houston, TX, USA, 5-9 December 201

Feasibility study and pilot cluster randomised controlled trial of the GoActive Intervention aiming to promote physical activity among adolescents: outcomes and lessons learnt

$\textbf{Objectives:}$ Assess the feasibility of implementing the GoActive intervention in secondary schools, to identify improvements, test study procedures, determine preliminary effectiveness to increase moderate-to-vigorous physical activity (MVPA), and inform power calculations to establish programme effectiveness. $\textbf{Setting:}$ Feasibility study (1 school) and pilot CRCT (2 intervention;1 control school(s)) $\textbf{Participants:}$ 460 participants (46.6% female; 13.2(0.4) years-old). $\textbf{Interventions:}$ 8-week intervention (2013) involved: classes choosing weekly activities encouraged by Mentors (older adolescents) and in-class peer-leaders. Students gain points for trying activities which are entered into an intra-mural competition. $\textbf{Primary and secondary outcome measures:}$ Planned quantitative (questionnaire) and qualitative (focus groups) process evaluation addressed enjoyment, confidence, participation, suggested improvements. Outcomes were assessed at baseline and follow-up (week 8) in pilot CRCT and included: accelerometer-assessed MVPA; adolescent-reported activity type, wellbeing, peer-support, shyness, sociability. ANCOVA was used to assess preliminary effectiveness as change in MVPA adjusted for baseline. $\textbf{Results:}$ All Year 9 students in intervention schools were exposed to the intervention; over all schools 77% of eligible students were measured. 71% boys and 74% girls found GoActive ‘fun’; 38% boys and 32% girls said it increased confidence and 64% boys and 59% girls said they would continue with a GoActive activity. Suggested improvements included more Mentorship; improved training; streamlined points recording. Pilot results indicated potential effectiveness ((adjusted mean difference (95%CI)p-value) (MVPA mins) 5.1(1.1,9.2)p=0.014)) and suggest recruitment of 16 schools (2400 adolescents) for a full trial. Compared to control, intervention students reported greater peer support 0.5(0.1,0.9)p=0.03, wellbeing 1.8(0.1, 3.4)p=0.04 but no difference in shyness/sociability. Participation in activity types approached significance (intervention group 2.3(-0.2,4.7)p=0.07 more activity types). $\textbf{Conclusions:}$ Results suggest feasibility and indicate potential effectiveness of GoActive to increase MVPA and support a fully-powered evaluation of effectiveness and cost-effectiveness. Process evaluation data was used to refine GoActive prior to a full trial. $\textbf{Trial Registration:}$ ISRCTN registry ISRCTN31583496.Funding for this study and the work of all authors was supported, wholly or in part, by the Centre for Diet and Activity Research (CEDAR), a UKCRC Public Health Research Centre of Excellence (RES-590-28-0002). Funding from the British Heart Foundation, Department of Health, Economic and Social Research Council, Medical Research Council, and the Wellcome Trust, under the auspices of the UK Clinical Research Collaboration, is gratefully acknowledged. The work of Kirsten Corder, Helen Brown and Esther M F van Sluijs was supported by the Medical Research Council (MC_UU_12015/7)

Responses of primate LGN cells to moving stimuli involve a constant background modulation by feedback from area MT

The feedback connections from the cortical motion area middle temporal (MT), to layer 6 of the primary visual cortex (V1), have the capacity to drive a cascaded feedback influence from the layer 6 cortico-geniculate cells back to the lateral geniculate nucleus (LGN) relay cells. This introduces the possibility of a re-entrant motion signal affecting the relay of the retinal input through the LGN to the visual cortex. The question is whether the response of LGN cells to moving stimuli involves a component derived from this feedback. By producing a reversible focal pharmacological block of the activity of an MT direction column we show the presence of such an influence from MT on the responses of magno, parvo and koniocellular cells in the macaque LGN. The pattern of effect in the LGN reflects the direction bias of the MT location inactivated. This suggests a moving stimulus is captured by iterative interactions in the circuit formed by visual cortical areas and visual thalamus

Electrochemistry education in the twenty-first century: the current landscape in the UK, challenges and opportunities

Electrochemistry education of future researchers is crucial if we are to decarbonise economies and reach targets for net zero, and this arguably begins with education in electrochemistry within undergraduate degrees. This paper reviews the teaching of electrochemistry in UK universities at the undergraduate degree level. We review where and how electrochemical concepts are introduced into chemistry, chemical engineering and materials science programmes. We provide some motivation for this review, which was stimulated by discussions from a workshop on the ‘Future of Fundamental Electrochemistry Research in the UK’, held in 2022. We summarise briefly how consensus on UK degree programme course content has been reached and inconsistencies that remain. Electrochemistry curriculum content from a convenience sample of UK universities, and disciplines, has been collected and is summarised, with a reflection on some trends. Finally, we present some implications for policy. A roadmap is suggested to ensure that the teaching of electrochemical fundamentals is addressed in the curriculum at an appropriate level to underpin the many technically relevant applications of electrochemistry that graduates will encounter in their further education or employment

Development of interfering RNA agents to inhibit SARS-associated coronavirus infection and replication.

published_or_final_versio

Potent inhibition of SARS-associated coronavirus (SCoV) infection and replication by type I interferons (IFN-α/β) but not by type II interferon (IFN-γ)

We sought to investigate the anti-severe acute respiratory syndrome (SARS)-associated coronavirus (SCoV) activities of type I (α and β) and type II (γ) interferons (IFN) in vitro. Type I IFNs protected cells from cytopathic effects (CPE) induced by SCoV, and inhibited viral genomic RNA replication in FRhk-4 cells (measured by quantitative RT-PCR) in a dose-dependent manner. Intracellular viral RNA copies were reduced 50% by IFN-α at a concentration of 25 U/ml and by IFN-β at a concentration of 14 U/ml. IFN-γ had fewer effects on inhibition of viral infection and replication. The type I IFN receptor signaling pathway in host cells is mainly involved in the inhibition of SCoV infection and replication. Type I IFNs could be used as potential agents for anti-SARS treatment.published_or_final_versio

A hybrid model for molecular-dynamics simulations of semiflexible main-chain liquid-crystalline polymer melts

2005-2006 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Trends in paediatric rheumatology referral times and disease activity indices over a ten-year period among children and young people with Juvenile Idiopathic Arthritis: results from the childhood arthritis prospective Study

OBJECTIVES: The medical management of JIA has advanced significantly over the past 10 years. It is not known whether these changes have impacted on outcomes. The aim of this analysis was to identify and describe trends in referral times, treatment times and 1-year outcomes over a 10-year period among children with JIA enrolled in the Childhood Arthritis Prospective Study. METHODS: The Childhood Arthritis Prospective Study is a prospective inception cohort of children with new-onset inflammatory arthritis. Analysis included all children recruited in 2001–11 with at least 1 year of follow-up, divided into four groups by year of diagnosis. Median referral time, baseline disease pattern (oligoarticular, polyarticular or systemic onset) and time to first definitive treatment were compared between groups. Where possible, clinical juvenile arthritis disease activity score (cJADAS) cut-offs were applied at 1 year. RESULTS: One thousand and sixty-six children were included in the analysis. The median time from symptom onset and referral to first paediatric rheumatology appointment (22.7–24.7 and 3.4–4.7 weeks, respectively) did not vary significantly (∼20% seen within 10 weeks of onset and ∼50% within 4 weeks of referral). For oligoarticular and polyarticular disease, 33.8–47 and 25.4–34.9%, respectively, achieved inactive disease by 1 year, with ∼30% in high disease activity at 1 year. A positive trend towards earlier definitive treatment reached significance in oligoarticular and polyarticular pattern disease. CONCLUSION: Children with new-onset JIA have a persistent delay in access to paediatric rheumatology care, with one-third in high disease activity at 1 year and no significant improvement over the past 10 years. Contributing factors may include service pressures and poor awareness. Further research is necessary to gain a better understanding and improve important clinical outcomes