Performance characterisation of 42.65 Gbit/s dual-gate asynchronous digital optical regenerator using single MZM

The tolerance of a 42.65 Gbit/s dual-gate asynchronous digital optical regenerator using a single Mach-Zehnder modulator to optical signal-to-noise-ratio degradation and chromatic dispersion is experimentally demonstrated

The Linear-Time-Invariance Notion of the Koopman Analysis-Part 2: Physical Interpretations of Invariant Koopman Modes and Phenomenological Revelations

This serial work presents a Linear-Time-Invariance (LTI) notion to the Koopman analysis, finding consistent and physically meaningful Koopman modes and addressing a long-standing problem of fluid-structure interactions: deterministically relating the fluid and structure. Part 1 (Li et al., 2022) developed the Koopman-LTI architecture and applied it to a pedagogical prism wake. By the systematic procedure, the LTI generated a sampling-independent Koopman linearization that captured all the recurring dynamics, finding six corresponding, orthogonal, and in-synch fluid excitation-structure response mechanisms. This Part 2 analyzes the six modal duplets' to underpin their physical interpretations, providing a phenomenological revelation of the subcritical prism wake. By the dynamical mode shape, results show that two mechanisms at St1=0.1242 and St5=0.0497 describe shear layer dynamics, the associated B\'ernard-K\'arm\'an shedding, and turbulence production, which together overwhelm the upstream and crosswind walls by instigating a reattachment-type of response. The on-wind walls' dynamical similarity renders them a spectrally unified fluid-structure interface. Another four harmonic counterparts, namely the subharmonic at St7=0.0683, the second harmonic at St3=0.2422, and two ultra-harmonics at St7 =0.1739 and St13=0.1935, govern the downstream wall. The 2P wake mode is also observed as an embedded harmonic of the bluff-body wake. Finally, this work discovered the vortex breathing phenomenon, describing the constant energy exchange in wake's circulation-entrainment-deposition processes. With the Koopman-LTI, one may pinpoint the exact excitations responsible for a specific structural response, or vice versa.Comment: 24 figures, 60 pages. Video files at https://drive.google.com/drive/folders/1AHdhUdAfNwlC1XUh-74PgQWW6jUHXJ5j?usp=sharin

Novel real-time homodyne coherent receiver using a feed-forward based carrier extraction scheme for phase modulated signals

We report a novel real-time homodyne coherent receiver based on a DPSK optical-electrical-optical (OEO) regenerator used to extract a carrier from carrier-less phase modulated signals based on feed-forward based modulation stripping. The performance of this non-DSP based coherent receiver was evaluated for 10.66Gbit/s BPSK signals. Self-homodyne coherent detection and homodyne detection with an injection-locked local oscillator laser was demonstrated. The performance was evaluated by measuring the electrical signal-to-noise (SNR) and recording the eye diagrams. Using injection-locking for the LO improves the performance and enables homodyne detection with optical injection-locking to operate with carrier-less BPSK signals without the need for polarization multiplexed pilot-tones

Novel synchronous DPSK optical regenerator based on a feed-forward based carrier extraction scheme

We experimentally demonstrate a novel synchronous 10.66Gbit/s DPSK OEO regenerator which uses a feed-forward carrier extraction scheme with an injection-locked laser to synchronize the regenerated signal wavelength to the incoming signal wavelength. After injection-locking, a low-cost DFB laser used at the regenerator exhibited the same linewidth characteristics as the narrow line-width transmitter laser. The phase regeneration properties of the regenerator were evaluated by emulating random Gaussian phase noise applied to the DPSK signal before the regenerator using a phase modulator driven by an arbitrary waveform generator. The overall performance was evaluated in terms of electrical eye-diagrams, BER measurements, and constellation diagrams

Evaluation of a surgical service in the chronic phase of a refugee camp: an example from the Thai-Myanmar border.

RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are.BACKGROUND: Published literature on surgical care in refugees tends to focus on the acute ('emergent') phase of crisis situations. Here we posit that there is a substantial burden of non-acute morbidity amenable to surgical intervention among refugees in the 'chronic' phase of crisis situations. We describe surgery for non-acute conditions undertaken at Mae La Refugee Camp, Thailand over a two year period. METHODS: Surgery was performed by a general surgeon in a dedicated room of Mae La Refugee Camp over May 2005 to April 2007 with minimal instruments and staff. We obtained the equivalent costs for these procedures if they were done at the local Thai District General Hospital. We also acquired the list (and costs) of acute surgical referrals to the District General Hospital over September 2006 to December 2007. RESULTS: 855 operations were performed on 847 patients in Mae La Refugee Camp (60.1% sterilizations, 13.3% 'general surgery', 5.6% 'gynaecological surgery', 17.4% 'mass excisions', 3.5% 'other'). These procedures were worth 2,207,500 THB (75,683.33 USD) at costs quoted by the District General Hospital. Total cost encountered for these operations (including staff costs, consumables, anaesthesia and capital costs such as construction) equaled 1,280,000 THB (42,666 USD). Pertaining to acute surgical referrals to District General hospital: we estimate that 356,411.96 THB (11,880.40 USD) worth of operations over 14 months were potentially preventable if these cases had been operated at an earlier, non-acute state in Mae La Refugee Camp. CONCLUSIONS: A considerable burden of non-acute surgical morbidity exists in 'chronic' refugee situations. An in-house general surgical service is found to be cost-effective in relieving some of this burden and should be considered by policy makers as a viable intervention

Comparison of frequency symmetric signal generation from a BPSK input using fiber and semiconductor-based nonlinear elements

This letter compares two nonlinear media for simultaneous carrier recovery and generation of frequency symmetric signals from a 42.7-Gb/s nonreturn-to-zero binary phase-shift-keyed input by exploiting four-wave mixing in a semiconductor optical amplifier and a highly nonlinear optical fiber for use in a phase-sensitive amplifier

Duration of exposure to multiple antibiotics is associated with increased risk of VRE bacteraemia: a nested case-control study.

BACKGROUND: VRE bacteraemia has a high mortality and continues to defy control. Antibiotic risk factors for VRE bacteraemia have not been adequately defined. We aimed to determine the risk factors for VRE bacteraemia focusing on duration of antibiotic exposure. METHODS: A retrospective matched nested case-control study was conducted amongst hospitalized patients at Cambridge University Hospitals NHS Foundation Trust (CUH) from 1 January 2006 to 31 December 2012. Cases who developed a first episode of VRE bacteraemia were matched 1:1 to controls by length of stay, year, specialty and ward type. Independent risk factors for VRE bacteraemia were evaluated using conditional logistic regression. RESULTS: Two hundred and thirty-five cases were compared with 220 controls. Duration of exposure to parenteral vancomycin, fluoroquinolones and meropenem was independently associated with VRE bacteraemia. Compared with patients with no exposure to vancomycin, those who received courses of 1-3 days, 4-7 days or >7 days had a stepwise increase in risk of VRE bacteraemia [conditional OR (cOR) 1.2 (95% CI 0.4-3.8), 3.8 (95% CI 1.2-11.7) and 6.6 (95% CI 1.9-22.8), respectively]. Other risk factors were: presence of a central venous catheter (CVC) [cOR 8.7 (95% CI 2.6-29.5)]; neutropenia [cOR 15.5 (95% CI 4.2-57.0)]; hypoalbuminaemia [cOR 8.5 (95% CI 2.4-29.5)]; malignancy [cOR 4.4 (95% CI 1.6-12.0)]; gastrointestinal disease [cOR 12.4 (95% CI 4.2-36.8)]; and hepatobiliary disease [cOR 7.9 (95% CI 2.1-29.9)]. CONCLUSIONS: Longer exposure to vancomycin, fluoroquinolones or meropenem was associated with VRE bacteraemia. Antimicrobial stewardship interventions targeting high-risk antibiotics are required to complement infection control procedures against VRE bacteraemia

Homeostatic regulation of the endoneurial microenvironment during development, aging and in response to trauma, disease and toxic insult

The endoneurial microenvironment, delimited by the endothelium of endoneurial vessels and a multi-layered ensheathing perineurium, is a specialized milieu intérieur within which axons, associated Schwann cells and other resident cells of peripheral nerves function. The endothelium and perineurium restricts as well as regulates exchange of material between the endoneurial microenvironment and the surrounding extracellular space and thus is more appropriately described as a blood–nerve interface (BNI) rather than a blood–nerve barrier (BNB). Input to and output from the endoneurial microenvironment occurs via blood–nerve exchange and convective endoneurial fluid flow driven by a proximo-distal hydrostatic pressure gradient. The independent regulation of the endothelial and perineurial components of the BNI during development, aging and in response to trauma is consistent with homeostatic regulation of the endoneurial microenvironment. Pathophysiological alterations of the endoneurium in experimental allergic neuritis (EAN), and diabetic and lead neuropathy are considered to be perturbations of endoneurial homeostasis. The interactions of Schwann cells, axons, macrophages, and mast cells via cell–cell and cell–matrix signaling regulate the permeability of this interface. A greater knowledge of the dynamic nature of tight junctions and the factors that induce and/or modulate these key elements of the BNI will increase our understanding of peripheral nerve disorders as well as stimulate the development of therapeutic strategies to treat these disorders

Patterns of Public Participation: Opportunity Structures and Mobilization from a Cross-National Perspective

PURPOSE: The paper summarizes data from twelve countries, chosen to exhibit wide variation, on the role and place of public participation in the setting of priorities. It seeks to exhibit cross-national patterns in respect of public participation, linking those differences to institutional features of the countries concerned. DESIGN/METHODOLOGY/APPROACH: The approach is an example of case-orientated qualitative assessment of participation practices. It derives its data from the presentation of country case studies by experts on each system. The country cases are located within the historical development of democracy in each country. FINDINGS: Patterns of participation are widely variable. Participation that is effective through routinized institutional processes appears to be inversely related to contestatory participation that uses political mobilization to challenge the legitimacy of the priority setting process. No system has resolved the conceptual ambiguities that are implicit in the idea of public participation. ORIGINALITY/VALUE: The paper draws on a unique collection of country case studies in participatory practice in prioritization, supplementing existing published sources. In showing that contestatory participation plays an important role in a sub-set of these countries it makes an important contribution to the field because it broadens the debate about public participation in priority setting beyond the use of minipublics and the observation of public representatives on decision-making bodies

Evolution of the hip fracture population: time to consider the future? A retrospective observational analysis

OBJECTIVE: To examine how the population with fractured neck of femur has changed over the last decade and determine whether they have evolved to become a more physically and socially dependent cohort. DESIGN: Retrospective cohort study of prospectively collected Standardised Audit of Hip Fractures of Europe data entered on to an institutional hip fracture registry. PARTICIPANTS: 10 044 consecutive hip fracture admissions (2000–2012). SETTING: A major trauma centre in the UK. RESULTS: There was a generalised increase in the number of admissions between 2000 (n=740) and 2012 (n=810). This increase was non-linear and best described by a quadratic curve. Assuming no change in the prevalence of hip fracture over the next 20 years, our hospital is projected to treat 871 cases in 2020 and 925 in 2030. This represents an approximate year-on-year increase of just over 1%. There was an increase in the proportion of male admissions over the study period (2000: 174 of 740 admissions (23.5%); 2012: 249 of 810 admissions (30.7%)). This mirrored national census changes within the geographical area during the same period. During the study period there were significant increases in the numbers of patients admitted from their own home, the proportion of patients requiring assistance to mobilise, and the proportion of patients requiring help with basic activities of daily living (all p<0.001). There was also a twofold to fourfold increase in the proportion of patients admitted with a diagnosis of cardiovascular disease, renal disease, diabetes and polypharmacy (use of >4 prescribed medications; all p<0.001). CONCLUSIONS: The expanding hip fracture population has increasingly complex medical, social and rehabilitation care needs. This needs to be recognised so that appropriate healthcare strategies and service planning can be implemented. This epidemiological analysis allows projections of future service need in terms of patient numbers and dependency