10Gbit/s modulation of a fast switching slotted Fabry-Pérot tunable laser

The device used is a three-section, 3mum wide ridge waveguide laser based on commercially available material. During the fabrication a series of slots are introduced into the front and back sections, which act as sites of internal reflections. The slots are etched to a depth that just penetrates the top of the upper waveguide resulting in an internal reflectance of-1% at each slot. The front, middle, and back sections are 180, 690 and 170 microns long respectively. In this work the back and middle sections are tied together electrically allowing simpler control of the device. By varying the applied DC currents, eight discrete channels are observed over a range of approximately 19nm

Bloodborne viral infection in Irish injecting drug users.

The aim of this study was to determine the prevalence of, and factors associated with, hepatitis C (HCV), hepatitis B (HBV) and HIV infections among injecting drug users (IDUs) against this background. A cross-sectional survey of participants in an addiction treatment clinic was carried out on seven hundred and thirty-five people IDU tested for antibody to HCV (anti-HCV) between September 1992 and September 1997. Socio-demographic and drug use characteristics were measured. Serology tests for anti-HCV, HBV surface antigen (HBsAg) and HIV. The vast majority (89%) commenced injecting since 1990. Prevalence of anti-HCV was 61.8% (453/733), of HBsAg was 1.0% (7/729) and of HIV was 1.2% (7/600). Logistic regression analyses indicated that longer history of injecting and increased daily drug expenditure were the only independent variables associated with significantly increased risk of HCV. The only characteristic associated with increased prevalence of HBsAg was a history of injecting prior to 1990 (3.8%, 3/80). HIV prevalence was significantly higher when aged over 24 years (3.7%, 6/162), when injecting commenced prior to 1990 (6.3%, 4/64) and when injecting over 5 years (6.5%, 4/62). The study concluded that HIV prevalence has sustained a low level in this population. Interventions which aim to halt transmission of HCV are necessary and will need to target IDU very early in their injecting careers and also those at risk of commencing to inject

Fast switching tunable laser sources for wavelength division multiplexing in passive optical access networks

Tunable laser structures with nanosecond switching time between wavelength channels and low-power injection locking are demonstrated on a low-cost platform. These lasers are suitable as source or slave lasers in WDM passive optical access networks

A novel two-section tunable discrete mode Fabry-PÉrot laser exhibiting nanosecond wavelength switching

A novel widely tunable laser diode is proposed and demonstrated. Mode selection occurs by etching perturbing slots into the laser ridge. A two-section device is realized with different slot patterns in each section allowing Vernier tuning. The laser operates at 1.3 mum and achieves a maximum output power of 10 mW. A discontinuous tuning range of 30 nm was achieved with a side mode suppression greater than 30 dB. Wavelength switching times of approximately 1.5 ns between a number of wavelength channels separated by 7 nm have been demonstrated

De novo transcriptome assembly of the Qatari pearl oyster Pinctada imbricata radiata

© 2019 The pearl oyster Pinctada imbricata radiata is an iconic species in Qatar, representing an integral part of the nation's cultural heritage and one of the main economic foundations upon which the nation developed. During the early part of the 20th century, nearly half the Qatar population was involved in the pearl oyster industry. However, the fishery has undergone steady decline since the 1930s, and the species is now under threat due to multiple confounding pressures. This manuscript presents the first de novo transcriptome of the Qatari pearl oyster assembled into 30,739 non-redundant coding sequences and with a BUSCO completeness score of 98.4%. Analysis of the transcriptome reveals the close evolutionary distance to the conspecific animal Pinctada imbricata fucata but also highlights differences in immune genes and the presence of distinctive transposon families, suggesting recent adaptive divergence. This data is made available for all to utilise in future studies on the species.This publication was made possible by the NPRP award [NPRP9-394-1-090 “The Pearl Oyster: from national icon to guardian of Qatar's marine environment”] from the Qatar National Research Fund (a member of Qatar Foundation). The findings herein reflect the work, and are solely the responsibility, of the authors. In addition, the authors would like to thank Prof. Eduarda Santos for advice regarding sequencing requirements and Mr. Mark Chatting and Mr. Reyniel Gasang for their support in the collection of the samples

Identification of genes important for cutaneous function revealed by a large scale reverse genetic screen in the mouse.

The skin is a highly regenerative organ which plays critical roles in protecting the body and sensing its environment. Consequently, morbidity and mortality associated with skin defects represent a significant health issue. To identify genes important in skin development and homeostasis, we have applied a high throughput, multi-parameter phenotype screen to the conditional targeted mutant mice generated by the Wellcome Trust Sanger Institute's Mouse Genetics Project (Sanger-MGP). A total of 562 different mouse lines were subjected to a variety of tests assessing cutaneous expression, macroscopic clinical disease, histological change, hair follicle cycling, and aberrant marker expression. Cutaneous lesions were associated with mutations in 23 different genes. Many of these were not previously associated with skin disease in the organ (Mysm1, Vangl1, Trpc4ap, Nom1, Sparc, Farp2, and Prkab1), while others were ascribed new cutaneous functions on the basis of the screening approach (Krt76, Lrig1, Myo5a, Nsun2, and Nf1). The integration of these skin specific screening protocols into the Sanger-MGP primary phenotyping pipelines marks the largest reported reverse genetic screen undertaken in any organ and defines approaches to maximise the productivity of future projects of this nature, while flagging genes for further characterisation

Knowledge regarding Hepatitis C among injecting drug users, Drugs: Education, Prevention and Policy,

Abstract Hepatitis C (HCV) is very prevalent among injecting drug users (IDU). Control of this infection poses a major challenge to harm reduction services. Education of all IDU regarding HCV constitutes part of the harm reduction programme. We sought to assess understanding of HCV among IDU attending an addiction treatment clinic and to identify whether or not those with increased contact with health professionals demonstrated better understanding. 105 IDU were interviewed to assess their knowledge regarding modes of transmission and chronicity of HCV infection. They had first injected an average of 10.0 years previously. Interviewees were more successful at identifying activities which carried a risk of HCV transmission than they were at identifying activities which posed no risk of infection. Over one third falsely believed that one could contract HCV infection even when injecting 'safely'. Understanding of the long term nature of HCV infection was also impaired. A group on methadone maintenance for a median period of 1.4 years failed to demonstrate significantly better knowledge than those attending for a 21-day detoxification. Those in frequent contact with a GP performed less well than those without such contact. Understanding of HCV among IDU is inadequate and must improve if primary prevention efforts are to succeed. We question the value of didactic approaches to educating IDU and call for a more experiential teaching style which may be more successful at countering prevalent misconceptions

Characterization of time-resolved laser differential phase using 3D complementary cumulative distribution functions

An experimental method for characterizing the time-resolved phase noise of a fast switching tunable laser is discussed. The method experimentally determines a complementary cumulative distribution function of the laser's differential phase as a function of time after a switching event. A time resolved bit error rate of differential quadrature phase shift keying formatted data, calculated using the phase noise measurements, was fitted to an experimental time-resolved bit error rate measurement using a field programmable gate array, finding a good agreement between the time-resolved bit error rates

Anti-DLL4 VNAR targeted nanoparticles for targeting of both tumour and tumour associated vasculature

Acknowledgements The authors acknowledge the Engineering and Physical Sciences Research Council (EPSRC) (S3802ASA) and the generous support of the Martin Family Foundation for funding the Ph.D. studentships of P. S. and A. L., respectively. This work was also partially funded through a US-Ireland R&D Partnership grant awarded by HSCNI (STL/5010/14), Medical Research Council UK (MC_PC_15013), and the Biotechnology and Biological Sciences Research Council (BBSRC) (BB/R009112/1).Peer reviewedPublisher PD

Effect of ret/PTC 1 rearrangement on transcription and post-transcriptional regulation in a papillary thyroid carcinoma model

BACKGROUND: microRNAs (miRNAs) are a group of non-coding single stranded RNAs measuring approximately 22 nt in length that have been found to control cell growth, differentiation and apoptosis. miRNAs negatively regulate their target genes and recently have been implicated in tumourigenesis. Furthermore, miRNA expression profiling correlates with various cancers, with these genes thought to act as both tumour suppressors and oncogenes. ret/PTC 1 is an oncogene with constitutive kinase activity implicated in the development of papillary thyroid carcinoma (PTC). This rearrangement leads to aberrant MAPK activation that is implicated in PTC tumourigenesis. AIM: The aim of this study was to identify the effect that ret/PTC 1 has on transcription and post-transcriptional regulation in PTC by using DNA microarray and microRNA analysis. RESULTS: DNA microarray analysis revealed a group of genes differentially expressed between normal thyroid cell lines and those harbouring a ret/PTC 1 rearrangement. Furthermore, a unique miRNA expression signature differentiated between PTC cell lines with ret/PTC 1 and a normal thyroid cell line. 21 miRNAs showed significant overexpression and 14 miRNAs showed underexpression in these cell lines when compared to normal thyroid. Several of these up/down regulated miRNAs may be involved in PTC pathogenesis