Double-pass configured fibre Mach-Zehnder interferometric optical filter for distributed fibre sensing

A double-pass configured all-fibre Mach-Zehnder interferometric optical filter has been developed and used in a distributed fibre-optic sensor for separation of Rayleigh and Brillouin signals. Its superior performance over a single-pass all-fibre Mach-Zehnder interferometer is highlighted by its 15dB improved rejection of the Rayleigh signal and comparable throughput

Characterisation of strain dependence of the Landau-Placzek ratio for distributed sensing

The authors report on the strain dependence of the Landau-Placzek ratio (LPR). This, together with the known temperature dependence of the LPR and the Brillouin frequency dependence on strain and temperature, may be used to form the basis of a combined distributed strain and temperature sensor

Piracy in the Ancient World: from Minos to Mohammed

This thesis is an historical analysis of the phenomenon of piracy in the ancient world from the Bronze Age to the Arab conquests. It is based on detailed examination and discussion of the ancient sources. There is a short introduction (Part One) which establishes the scope of the enquiry, defines the subject and surveys modern scholarly literature. Part Two (The Image of Ancient Piracy) consists of a study of the Greek and Latin vocabulary for piracy, and six separate studies of Classical literature, from Homer to the fourth century A.D. These studies analyze the development of the literary image of pirates and piracy, from the ambivalent attitude of the Homeric poems, to the wholly negative presentation of pirates and piracy found in the works of later writers. Part Three (War and Piracy) analyzes the early similarity between warfare and piracy, the gradual emergence of distinctions between the two, warfare as a promoter of piracy, and the involvement of pirates in warfare. Part Four (Trade and Piracy) is an analysis of the relationship between piracy and various forms of trade. The importance of piracy as both a contributor and a threat to long-distance maritime trade is analyzed, as well as the involvement of pirates in the slave trade. The link between trade and the suppression of piracy is also discussed. Part Five (The Suppression of Piracy) examines in detail attempts to suppress piracy from the Classical period to the end of the Roman Empire. Emphasis is laid upon the practical and political implications of suppression, and the relative ineffectiveness of most measures until the Late Republic and Early Principate, when piracy was suppressed with considerable success. There follows a brief statement of the general conclusions (Part Six) and suggestions for further research. One map and a bibliography are included

Dynamics of a ring of pulse-coupled oscillators: group-theoretic approach

We use group-theoretic methods to analyze phase-locking in a ring of identical integrate-and-fire oscillators with distributed delays. It is shown how certain phase-locked solutions emerge through symmetry breaking bifurcations as some characteristic delay of the system is varied. The reduction to a phase-coupled model in the weak coupling regime is discussed

Identification of proteomic signatures associated with depression and psychotic depression in post-mortem brains from major depression patients

Major depressive disorder (MDD) is a leading cause of disability worldwide and results tragically in the loss of almost one million lives in Western societies every year. This is due to poor understanding of the disease pathophysiology and lack of empirical medical tests for accurate diagnosis or for guiding antidepressant treatment strategies. Here, we have used shotgun proteomics in the analysis of post-mortem dorsolateral prefrontal cortex brain tissue from 24 MDD patients and 12 matched controls. Brain proteomes were pre-fractionated by gel electrophoresis and further analyzed by shotgun data-independent label-free liquid chromatography-mass spectrometry. This led to identification of distinct proteome fingerprints between MDD and control subjects. Some of these differences were validated by Western blot or selected reaction monitoring mass spectrometry. This included proteins associated with energy metabolism and synaptic function and we also found changes in the histidine triad nucleotide-binding protein 1 (HINT1), which has been implicated recently in regulation of mood and behavior. We also found differential proteome profiles in MDD with (n=11) and without (n=12) psychosis. Interestingly, the psychosis fingerprint showed a marked overlap to changes seen in the brain proteome of schizophrenia patients. These findings suggest that it may be possible to contribute to the disease understanding by distinguishing different subtypes of MDD based on distinct brain proteomic profiles

Proteomic changes in serum of first onset, antidepressant drug-naïve major depression patients

Major depressive disorder (MDD) is a complex and multi-factorial disorder. Although genetic factors and other molecular aspects of MDD have been widely studied, the underlying pathological mechanisms are still mostly unknown. We sought to investigate the pathophysiology of MDD by identifying and characterising serum molecular differences and their correlation to symptom severity in first onset, antidepressant drug-naïve MDD patients. We performed an exploratory molecular profiling study on serum samples of MDD patients and controls using multiplex immunoassay and label-free liquid chromatography mass spectrometry in data independent mode (LC-MSE). We included two independent cohorts of first onset, antidepressant drug-naïve MDD patients (n = 23 and 15) and matched controls (n = 42 and 21) in our study in order to validate the results. The main outcome included the following list of circulatory molecules changing and/or correlating to symptom severity: angiotensin-converting enzyme, acute phase proteins (e.g. ferritin and serotransferrin), brain-derived neurotrophic factor, complement component C4-B, cortisol, cytokines (e.g. macrophage migration inhibitory factor and interleukin-16), extracellular newly identified receptor for advanced glycosylation end products-binding protein, growth hormone and superoxide dismutase-1. This study provides evidence of an increased pro-inflammatory and oxidative stress response, followed by a hyperactivation of the HPA-axis in the acute stages of first onset MDD, as well as a dysregulation in growth factor pathways. These findings help to elucidate MDD related pathways in more detail and further studies may lead to identification of novel drug targets, inc