Development of electrically pumped vertical external cavity surface emitting lasers (EP-VECSELs).

In this thesis design, development and realisation of a substrate emission electrically pumped vertical external cavity surface emitting lasers (EP-VECSELs) emitting in the 980 nm wavelength range is discussed. Chapter 1 provides a literature review of the relevant VCSEL and (OP-VECSEL) technology required for the design of an EP-VECSEL. In chapter 2, different areas of the device design are highlighted, including electrical and optical performance of the distributed Bragg reflectors (DBRs), active region design, device detuning and antirefiective coating design. Chapter 3 provides a description of the method used to fabricate EP-VECSEL devices and focuses on optimisation of different process steps, namely the trench etch profile and depth, as well as the contact metalisation. A method for characterising the detuning of a wafer is also presented. In chapter 4 measurements of fabricated EP-VECSEL are presented, with a method for the characterisation of the EP-VECSEL material by modulating the output coupler mirror reflectivity demonstrated. This method is then used to examine the affect of different substrate dopings on device performance. Data is also presented on beam quality, power scaling and thermal properties. Chapter 5 investigates methods for improving electrical aspects of device operation, with improved nand p DBR designs proposed. In addition, analysis of SIMS data for an EP-VECSEL and n-DBR are presented, along with an investigation of the top contact geometry. In chapter 6 a discussion of the QW active region is provided, first by analysing the epitaxial material used in chapter 4 and then proposing improvements to the growth process. A comparison of a 3, 6 and 9 QW active region is then presented, where the trade offs in the optimum number of QWs are examined. Finally, this thesis is summarised and a new device design is proposed from the findings

World netball cardiac screening guidelines

Sudden cardiac adverse events remain an area of concern in sport. The precise risk for netball athletes is unknown but the annual incidence of sudden cardiac death in sports is reported at 0.5-2 cases in 100 000 young competitive athletes between the ages of 12-35 years. Cardiac screening in the sport and exercise medicine context aims at identifying pathologies associated with catastrophic events when combined with physical activity. There is an ongoing debate relating to the standardisation of the pre-participatory medical assessment (PPMA). World Netball (WN) commissioned a cardiac screening policy (13 March 2022). The minimum PPMA recommended by World Netball is a history, physical examination, and a resting 12-lead electrocardiogram (ECG). ECGs should be interpreted in accordance with athletespecific ECG interpretation criteria. Expansion of sports cardiology experience and infrastructure, in combination with universal emergency response planning for sudden cardiac arrest, is intended to safeguard athlete health and player welfare in WN.

ComplexViewer: visualization of curated macromolecular complexes.

SUMMARY: Proteins frequently function as parts of complexes, assemblages of multiple proteins and other biomolecules, yet network visualizations usually only show proteins as parts of binary interactions. ComplexViewer visualizes interactions with more than two participants and thereby avoids the need to first expand these into multiple binary interactions. Furthermore, if binding regions between molecules are known then these can be displayed in the context of the larger complex. AVAILABILITY AND IMPLEMENTATION: freely available under Apache version 2 license; EMBL-EBI Complex Portal: http://www.ebi.ac.uk/complexportal; Source code: https://github.com/MICommunity/ComplexViewer; Package: https://www.npmjs.com/package/complexviewer; http://biojs.io/d/complexviewer. Language: JavaScript; Web technology: Scalable Vector Graphics; Libraries: D3.js. CONTACT: [email protected] or [email protected]

Proposal for a Standard Representation of Two-Dimensional Gel Electrophoresis Data

The global analysis of proteins is now feasible due to improvements in techniques such as two-dimensional gel electrophoresis (2-DE), mass spectrometry, yeast two-hybrid systems and the development of bioinformatics applications. The experiments form the basis of proteomics, and present significant challenges in data analysis, storage and querying. We argue that a standard format for proteome data is required to enable the storage, exchange and subsequent re-analysis of large datasets. We describe the criteria that must be met for the development of a standard for proteomics. We have developed a model to represent data from 2-DE experiments, including difference gel electrophoresis along with image analysis and statistical analysis across multiple gels. This part of proteomics analysis is not represented in current proposals for proteomics standards. We are working with the Proteomics Standards Initiative to develop a model encompassing biological sample origin, experimental protocols, a number of separation techniques and mass spectrometry. The standard format will facilitate the development of central repositories of data, enabling results to be verified or re-analysed, and the correlation of results produced by different research groups using a variety of laboratory techniques

Idiotypic DNA vaccination for the treatment of multiple myeloma: safety and immunogenicity in a phase I clinical study

We report on the safety and immunogenicity of idiotypic DNA vaccination in a phase I, non-randomised, open-label study in patients with multiple myeloma. The study used DNA fusion gene vaccines encoding patient-specific single chain variable fragment, or idiotype (Id), linked to fragment C (FrC) of tetanus toxin. Patients in complete or partial response following high-dose chemotherapy and autologous stem cell transplant were vaccinated intramuscularly with 1 mg DNA on six occasions, beginning at least 6 months post-transplant; follow-up was to week 52. Fourteen patients were enrolled on study and completed vaccinations. Idiotypic DNA vaccines were well tolerated with vaccine-related adverse events limited to low-grade constitutional symptoms. FrC- and Id-specific T-cell responses were detected by ex vivo ELISPOT in 9/14 and 3/14 patients, respectively. A boost of pre-existing anti-FrC antibody (Ab) was detected by ELISA in 8/14 patients, whilst anti-Id Ab was generated in 1/13 patients. Overall, four patients (29 %) made an immune response to FrC and Id, with six patients (43 %) responding to FrC alone. Over the 52-week study period, serum paraprotein was undetectable, decreased or remained stable for ten patients (71 %), whilst ongoing CR/PR was maintained for 11 patients (79 %). The median time to progression was 38.0 months for 13/14 patients. Overall survival was 64 % after a median follow-up of 85.6 months

Ground reaction force, spinal kinematics and their relationship to lower back pain and injury in cricket fast bowling: A review

BACKGROUND: Fast bowlers display a high risk of lower back injury and pain. Studies report factors that may increase this risk, however exact mechanisms remain unclear. OBJECTIVE: To provide a contemporary analysis of literature, up to April 2016, regarding fast bowling, spinal kinematics, ground reaction force (GRF), lower back pain (LBP) and pathology. METHOD: Key terms including biomechanics, bowling, spine and injury were searched within MEDLINE, Google Scholar, SPORTDiscuss, Science Citation Index, OAIster, CINAHL, Academic Search Complete, Science Direct and Scopus. Following application of inclusion criteria, 56 studies (reduced from 140) were appraised for quality and pooled for further analysis. RESULTS: Twelve times greater risk of lumbar injury was reported in bowlers displaying excessive shoulder counter-rotation (SCR), however SCR is a surrogate measure which may not describe actual spinal movement. Little is known about LBP specifically. Weighted averages of 5.8 ± 1.3 times body weight (BW) vertically and 3.2 ± 1.1 BW horizontally were calculated for peak GRF during fast bowling. No quantitative synthesis of kinematic data was possible due to heterogeneity of reported results. CONCLUSIONS: Fast bowling is highly injurious especially with excessive SCR. Studies adopted similar methodologies, constrained to laboratory settings. Future studies should focus on methods to determine biomechanics during live play

1.5 {\mu}m Epitaxially Regrown Photonic Crystal Surface Emitting Laser Diode

We present an InP-based epitaxially regrown photonic crystal surface emitting laser diode, lasing in quasi- CW conditions at 1523nm.Comment: 4 pages, 5 figures, journal submission for revie

Silicon-based single quantum dot emission in the telecoms C‑band

We report the observation of single quantum dot (QD) emission in the telecoms C-band (1530−1565 nm) from an InAs QD structure grown on a Si substrate. A large red-shift of the emission is achieved by capping InAs QDs with a thin GaAsSb layer. Sharp lines, representing emission from single QDs, are observed out to wavelengths as long as 1540 nm. Comparison is made to the optical properties of a nominally identical active region structure grown on a GaAs substrate. Single QD emission from a Si-based system at 1500 nm has the potential for single photon sources compatible with current optical fibers and reduced complexity of integration with drive electronics

Analysing radiative and non-radiative recombination in InAs QDs on Si for integrated laser applications

Three InAs quantum dot (QD) samples with dislocation filter layers (DFLs) are grown on Si substrates with and without in-situ annealing. Comparison is made to a similar structure grown on a GaAs substrate. The three Si grown samples have different dislocation densities in their active region as revealed by structural studies. By determining the integrated emission as a function of laser power it is possible to determine the power dependence of the radiative efficiency and compare this across the four samples. The radiative efficiency increases with decreasing dislocation density; this also results in a decrease in the temperature quenching of the PL. A laser structures grown on Si and implementing the same optimum DFL and annealing procedure exhibits a greater than 3 fold reduction in threshold current as well as a two fold increase in slope efficiency in comparison to a device in which no annealing is applied. © (2016) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only

BioTorrents: A File Sharing Service for Scientific Data

The transfer of scientific data has emerged as a significant challenge, as datasets continue to grow in size and demand for open access sharing increases. Current methods for file transfer do not scale well for large files and can cause long transfer times. In this study we present BioTorrents, a website that allows open access sharing of scientific data and uses the popular BitTorrent peer-to-peer file sharing technology. BioTorrents allows files to be transferred rapidly due to the sharing of bandwidth across multiple institutions and provides more reliable file transfers due to the built-in error checking of the file sharing technology. BioTorrents contains multiple features, including keyword searching, category browsing, RSS feeds, torrent comments, and a discussion forum. BioTorrents is available at http://www.biotorrents.net