Scalable Optical Packet Switches for Multiple Data Formats and Data Rates Packets

We demonstrate an optical packet switch (OPS) subsystem employing in-band labeling to allow for transparent routing of packets with multiple data formats and data bit rates. Packets employing in-band labels can be processed without the need to reconfigure the label processor and the switch when changing data format and bit-rate. The label processor is based on asynchronous optical signal processing in combination with a simple electronic combinatory network. This makes the label processor capable to process a large number of labels with low latency time

Optical switching and detection of 640 Gbits/s optical time-division multiplexed data packets transmitted over 50 km of fiber

We demonstrate 1×4 optical-packet switching with error-free transmission of 640¿Gbits/s single-wavelength optical time-division multiplexed data packets including clock distribution and short pulse generation for optical time demultiplexing based on a cavityless pulse source

High-speed optical signal processing for telecom applications

Abstract-We discuss high-speed optical signal processing for telecom applications. We focus on the optical wavelength conversion and self-clocking, respectively. In the optical wavelength conversion, we report 40 Gb/s wavelength conversion that is capable of converting the same wavelength using a single semiconductor optical amplifier. Experimental proofs are presented. In addition, we report a novel self-clocking method based on in-band clock pilot insertion at the transmission data signal. The method provides clock recovery without an ultrafast phase comparator and a phase-locked loop in the receiver. Fast synchronization, low timing jitter and a highly stable recovered clock is demonstrated from 160 Gb/s OTDM data signal after 51-km fiber transmission

Scalable optical packet switches for multiple data formats and data rates packets

Abstract-We demonstrate an optical packet switch (OPS) subsystem employing in-band labeling to allow for transparent routing of packets with multiple data formats and data bit rates. Packets employing in-band labels can be processed without the need to reconfigure the label processor and the switch when changing data format and bit-rate. The label processor is based on asynchronous optical signal processing in combination with a simple electronic combinatory network. This makes the label processor capable to process a large number of labels with low latency time ( 3 ns) without complicated and power-hungry high-speed packet clock recovery and serializer/deserializer circuits. Experimental results show error-free operation of 1 64 OPS subsystem for 160-Gb/s return-to-zero ON-OFF keying and 120-Gb/s nonreturn-to-zero differential phase-shift keying multiwavelength packets. Index Terms-Fiber Bragg grating (FBG), label processor, optical packet switching, optical signal processing, optical switch

Adapted motivational interviewing to improve the uptake of treatment for glaucoma in Nigeria: study protocol for a randomized controlled trial.

BACKGROUND: Glaucoma is a chronic eye disease associated with irreversible visual loss. In Africa, glaucoma patients often present late, with very advanced disease. One-off procedures, such as laser or surgery, are recommended in Africa because of lack of or poor adherence to medical treatment. However, acceptance of surgery is usually extremely low. To prevent blindness, adherence to treatment needs to improve, using acceptable, replicable and cost-effective interventions. After reviewing the literature and interviewing patients in Bauchi (Nigeria) motivational interviewing (MI) was selected as the intervention for this trial, with adaptation for glaucoma (MIG). MI is designed to strengthen personal motivation for, and commitment to a specific goal by eliciting and exploring a person's reasons for change within an atmosphere of acceptance and compassion. The aim of this study is to assess whether MIG increases the uptake of laser or surgery amongst glaucoma patients where this is the recommended treatment. The hypothesis is that MIG increases the uptake of treatment. This will be the first trial of MI in Africa. METHODS: This is a hospital based, single centre, randomized controlled trial of MIG plus an information sheet on glaucoma and its treatment (the latter being "standard care") compared with standard care alone for glaucoma patients where the treatment recommended is surgery or laser.Those eligible for the trial are adults aged 17 years and above who live within 200 km of Bauchi with advanced glaucoma where the examining ophthalmologist recommends surgery or laser. After obtaining written informed consent, participants will be randomly allocated to MIG plus standard care, or standard care alone. Motivational interviewing will be delivered in Hausa or English by one of two MIG trained personnel. One hundred and fifty participants will be recruited to each arm. The primary outcome is the proportion of participants undergoing laser or surgery within two months of the date given to re attend for the procedure. MIG quality will be assessed using the validated MI treatment integrity scale. DISCUSSION: Motivational interviewing may be an important tool to increase the acceptance of treatment for glaucoma. The approach is potentially scalable and may be useful for other chronic conditions in Africa. TRIAL REGISTRATION: ISRCTN79330571 (Controlled-Trials.com)

Development of the conceptual framework for the Eye-Drop Satisfaction Questionnaire (EDSQ©) in glaucoma using a qualitative study

<p>Abstract</p> <p>Background</p> <p>Compliance is a major issue in glaucoma care. It is usually poor in glaucomatous patients, and may ultimately result in an acceleration of the disease progression and a risk of blindness. Reasons for this poor compliance are complex and multifactorial, amongst which patient satisfaction can be counted. The objective of this study was to develop a questionnaire to assess patient satisfaction and compliance with eye-drop treatment.</p> <p>Methods</p> <p>A qualitative study was carried out to develop the questionnaire. An interview guide was developed based on a literature review. Structured interviews of fifteen French and English patients with primary open-angle glaucoma or intraocular hypertension were conducted by trained interviewers of the native language of the interviewees. General concepts and subconcepts were identified from the transcripts. The questionnaire was developed using the patient verbatim, and submitted to six patients (French and English) for cognitive debriefing. Following patients' comments, items were modified and restructured, and a pilot questionnaire was designed.</p> <p>Results</p> <p>Analysis of data from the interviews with patients and clinicians resulted in the elicitation of concepts related to patient satisfaction and compliance with glaucomatous treatment. These were further refined and used to generate a test questionnaire, which consisted of 46 items grouped into 6 domains: patient characteristics, treatment characteristics, patient-clinician relationship, patient experience with the disease and the treatment, interaction between the patient and the treatment, and patient knowledge of the disease and the treatment.</p> <p>Conclusion</p> <p>The Eye-Drop Satisfaction Questionnaire (EDSQ) conceptual framework and items were developed simultaneously in French and in English. This questionnaire could be used to evaluate patient satisfaction and compliance with eye-drop treatment and would facilitate the identification of patients at risk of being non-compliant prior to clinical trials or innovative device tests. A psychometric study is under way to validate the questionnaire.</p