AN INTRODUCTION AND BACKGROUND TO THE BAITFISH RESEARCH PROJECT IN EASTERN INDONESIA

Pole-and-line fishing for tuna is a multi-million dollar industry in eastern Indonesia that employs many people, supports several canneries and generates export income

Heart rate variability and short duration spaceflight: relationship to post-flight orthostatic intolerance

BACKGROUND: Upon return from space many astronauts experience symptoms of orthostatic intolerance. Research has implicated altered autonomic cardiovascular regulation due to spaceflight with further evidence to suggest that there might be pre-flight autonomic indicators of post-flight orthostatic intolerance. We used heart rate variability (HRV) to determine whether autonomic regulation of the heart in astronauts who did or did not experience post-flight orthostatic intolerance was different pre-flight and/or was differentially affected by short duration (8 – 16 days) spaceflight. HRV data from ten-minute stand tests collected from the 29 astronauts 10 days pre-flight, on landing day and three days post-flight were analysed using coarse graining spectral analysis. From the total power (P(TOT)), the harmonic component was extracted and divided into high (P(HI): >0.15 Hz) and low (P(LO): = 0.15 Hz) frequency power regions. Given the distribution of autonomic nervous system activity with frequency at the sinus node, P(HI)/P(TOT )was used as an indicator of parasympathetic activity; P(LO)/P(TOT )as an indicator of sympathetic activity; and, P(LO)/P(HI )as an estimate of sympathovagal balance. RESULTS: Twenty-one astronauts were classified as finishers, and eight as non-finishers, based on their ability to remain standing for 10 minutes on landing day. Pre-flight, non-finishers had a higher supine P(HI)/P(TOT )than finishers. Supine P(HI)/P(TOT )was the same pre-flight and on landing day in the finishers; whereas, in the non-finishers it was reduced. The ratio P(LO)/P(HI )was lower in non-finishers compared to finishers and was unaffected by spaceflight. Pre-flight, both finishers and non-finishers had similar supine values of P(LO)/P(TOT), which increased from supine to stand. Following spaceflight, only the finishers had an increase in P(LO)/P(TOT )from supine to stand. CONCLUSIONS: Both finishers and non-finishers had an increase in sympathetic activity with stand on pre-flight, yet only finishers retained this response on landing day. Non-finishers also had lower sympathovagal balance and higher pre-flight supine parasympathetic activity than finishers. These results suggest pre-flight autonomic status and post-flight impairment in autonomic control of the heart may contribute to orthostatic intolerance. The mechanism by which higher pre-flight parasympathetic activity might contribute to post-flight orthostatic intolerance is not understood and requires further investigation

Design Principles for Plasmonic Nanoparticle Devices

For all applications of plasmonics to technology it is required to tailor the resonance to the optical system in question. This chapter gives an understanding of the design considerations for nanoparticles needed to tune the resonance. First the basic concepts of plasmonics are reviewed with a focus on the physics of nanoparticles. An introduction to the finite element method is given with emphasis on the suitability of the method to nanoplasmonic device simulation. The effects of nanoparticle shape on the spectral position and lineshape of the plasmonic resonance are discussed including retardation and surface curvature effects. The most technologically important plasmonic materials are assessed for device applicability and the importance of substrates in light scattering is explained. Finally the application of plasmonic nanoparticles to photovoltaic devices is discussed.Comment: 29 pages, 15 figures, part of an edited book: "Linear and Non-Linear Nanoplasmonics

Endothelial MAPKs Direct ICAM-1 Signaling to Divergent Inflammatory Functions.

Lymphocyte transendothelial migration (TEM) is critically dependent on intraendothelial signaling triggered by adhesion to ICAM-1. Here we show that endothelial MAPKs ERK, p38, and JNK mediate diapedesis-related and diapedesis-unrelated functions of ICAM-1 in cerebral and dermal microvascular endothelial cells (MVECs). All three MAPKs were activated by ICAM-1 engagement, either through lymphocyte adhesion or Ab-mediated clustering. MAPKs were involved in ICAM-1-dependent expression of TNF-α in cerebral and dermal MVECs, and CXCL8, CCL3, CCL4, VCAM-1, and cyclooxygenase 2 (COX-2) in cerebral MVECs. Endothelial JNK and to a much lesser degree p38 were the principal MAPKs involved in facilitating diapedesis of CD4(+) lymphocytes across both types of MVECs, whereas ERK was additionally required for TEM across dermal MVECs. JNK activity was critical for ICAM-1-induced F-actin rearrangements. Furthermore, activation of endothelial ICAM-1/JNK led to phosphorylation of paxillin, its association with VE-cadherin, and internalization of the latter. Importantly ICAM-1-induced phosphorylation of paxillin was required for lymphocyte TEM and converged functionally with VE-cadherin phosphorylation. Taken together we conclude that during lymphocyte TEM, ICAM-1 signaling diverges into pathways regulating lymphocyte diapedesis, and other pathways modulating gene expression thereby contributing to the long-term inflammatory response of the endothelium

Preventing PTSD, depression and associated health problems in student paramedics: Protocol for PREVENT-PTSD, a randomised controlled trial of supported online cognitive training for resilience versus alternative online training and standard practice

This the author accepted manuscript. The final version is available from the publisher via the DOI in this record.Introduction: Emergency workers dedicate their lives to promoting public health and safety, yet suffer higher rates of post-traumatic stress disorder (PTSD) and major depression (MD) compared with the general population. They also suffer an associated increased risk for physical health problems, which may be linked to specific immunological and endocrine markers or changes in relevant markers. Poor physical and mental health is costly to organisations, the National Health Service and society. Existing interventions aimed at reducing risk of mental ill health in this population are not very successful. More effective preventative interventions are urgently needed. We first conducted a large-scale prospective study of newly recruited student paramedics, identifying two cognitive factors (rumination and resilience appraisals) that predicted episodes of PTSD and MD over a 2-year period. We then developed internet-delivered cognitive training for resilience (iCT-R), a supported online intervention, to modify cognitive predictors. This protocol is for a randomised controlled trial to evaluate the efficacy of the resilience intervention. Methods and analysis: 570 student paramedics will be recruited from participating universities. They will be randomly allocated to iCT-R or to supported online training of an alternative, widely available intervention or to training-as-usual. Follow-up will occur after the intervention/standard practice period and at 6, 12 and 24 months. Primary outcomes include rates of PTSD and MD and subsydnromal PTSD and MD, measured by the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, fifth edition, the Patient-Health Questionnaire-9 and the Post-traumatic Stress Disorder Checklist for Diagnostic and Statistical Manual of Mental Disorders, fifth edition. Secondary outcomes include measures of resilience, rumination, anxiety, psychological distress, well-being, salivary cortisol, plasma levels of C-reactive protein, smoking and alcohol use, weight gain, sleep problems, health-related quality of life, health resource utilisation and productivity. Ethics and dissemination: The Medical Sciences Inter-Divisional Research Ethics Committee at the University of Oxford granted approval, reference: R44116/RE001. The results will be published in a peer-reviewed journal. Access to raw data and participant information will be available only to members of the research team. Trial registration number ISRCTN16493616; Pre-results.Wellcome TrustMQ: Transforming Mental HealthNIHR: National Institute for Health Researc

Effective permittivity of random plasmonic composites

An effective-medium theory (EMT) is developed to predict the effective permittivity \epsilon_eff of dense random dispersions of high optical-conductivity metals such as Ag, Au and Cu. Dependence of \epsilon_eff on the volume fraction \phi, a microstructure parameter \kappa related to the static structure factor and particle radius a is studied. In the electrostatic limit, the upper and lower bounds of \kappa correspond to Maxwell-Garnett and Bruggeman EMTs respectively. Finite size effects are significant when |\beta^2(ka/n)^3| becomes O(1) where \beta, k, and n denote the nanoparticle polarizability, wavenumber and matrix refractive index respectively. The coupling between the particle and effective medium results in a red-shift in the resonance peak, a non-linear dependence of \epsilon_eff on \phi, and Fano resonance in \epsilon_eff.Comment: Manuscript submitted to J. Opt. Soc. Am. B. 33 page

A review of the optical properties of alloys and intermetallics for plasmonics

Alternative materials are required to enhance the efficacy of plasmonic devices. We discuss the optical properties of a number of alloys, doped metals, intermetallics, silicides, metallic glasses and high pressure materials. We conclude that due to the probability of low frequency interband transitions, materials with partially occupied d-states perform poorly as plasmonic materials, ruling out many alloys, intermetallics and silicides as viable. The increased probability of electron-electron and electron-phonon scattering rules out many doped and glassy metals.Comment: 26 pages, 10 figures, 3 table

The Deformation of Expanded Clay Syntactic Foams during Compression Characterized by Acoustic Emission

The deformation and failure mechanisms in syntactic foams with different metal matrices were investigated in this study. The syntactic foams were produced by the infiltration method using lightweight expanded clay particles (LECA) as a space holder and commercially pure Al or eutectic Al-12%Si alloy for the matrices. The samples were compressed at room temperature; simultaneously, the acoustic emission (AE) response and the surface deformation were monitored and collated with the deformation curves. In the case of the Al foam, ductile behavior with long plateau stress was observed. During this plateau regime, multiple active shear bands were detected. In contrast, the AlSi12 foam exhibited more brittle deformation behavior. At the end of the quasi-linear stage, the localization of the strain started within one large shear band, accompanied by a significant stress drop. The AE analysis revealed that the deformation was mostly governed by the fracture of LECA particles and the plastic deformation of the matrix material for both types of foams. After strain localization, in the case of the AlSi12 foam, the fracture of the matrix became significant, causing the deterioration of the sample. As for the Al foam, besides the fracture of the LECA particles, the plastic deformation of the matrix played an important role in preventing the foam from falling apart

The impact of fishing of marine birds

Birds are the most conspicuous, wide-ranging, and easily studied organisms in the marine environment. They can be both predators and scavengers, and they can be harmed by and can benefit from fishing activities. The effects of fishing on birds may be direct or indirect. Most direct effects involve killing by fishing gear, although on a lesser scale some fishing activities also disturb birds. Net fisheries and hook fisheries have both had serious negative effects at the population level. Currently, a major negative impact comes from the by-catch of albatrosses and petrels in long-lines in the North Pacific and in the Southern Ocean. High seas drift nets have had, prior to the banning of their use, a considerable impact on seabirds in the northern Pacific, as have gillnets in south-west Greenland, eastern Canada, and elsewhere. Indirect effects mostly work through the alteration in food supplies. Many activities increase the food supply by providing large quantities of discarded fish and wastes, particularly those from large, demersal species that are inaccessible to seabirds, from fishing vessels to scavengers. Also, fishing has changed the structure of marine communities. Fishing activities have led to depletion of some fish species fed upon by seabirds, but may also lead to an increase in small fish prey by reducing numbers of larger fish that may compete with birds. Both direct and indirect effects are likely to have operated at the global population level on some species. Proving the scale of fisheries effects can be difficult because of confounding and interacting combinations with other anthropogenic effects (pollution, hunting, disturbance) and oceanographic factors. Effects of aquaculture have not been included in the revie