22 research outputs found
Miniature photonic-crystal hydrophone optimized for ocean acoustics
This work reports on an optical hydrophone that is insensitive to hydrostatic
pressure, yet capable of measuring acoustic pressures as low as the background
noise in the ocean in a frequency range of 1 Hz to 100 kHz. The miniature
hydrophone consists of a Fabry-Perot interferometer made of a photonic-crystal
reflector interrogated with a single-mode fiber, and is compatible with
existing fiber-optic technologies. Three sensors with different acoustic power
ranges placed within a sub-wavelength sized hydrophone head allow a high
dynamic range in the excess of 160 dB with a low harmonic distortion of better
than -30 dB. A method for suppressing cross coupling between sensors in the
same hydrophone head is also proposed. A prototype was fabricated, assembled,
and tested. The sensitivity was measured from 100 Hz to 100 kHz, demonstrating
a minimum detectable pressure down to 12 {\mu}Pa (1-Hz noise bandwidth), a
flatband wider than 10 kHz, and very low distortion
Non-Western small states:activists or survivors?
In this introduction to the collection, we explain its focus on non-Western small states. While the terms ‘non-Western’ and ‘small states’ are problematic – we discuss these problems here – the smallness and non-Westerness of the states studied by the contributing authors set them apart in a way that has attracted little academic attention so far. They allow them to operate with fewer normative and practical constraints than their bigger, Western counterparts; offer them a wide range of (often historically forged) political ties; and force them to draw on a diversity of approaches and strategic thinking, and a creativity, that they are too rarely credited for. Non-Western small states, rather than being mere survivors constrained to the world’s periphery, are better understood as activist states intent on existing. The collection offers a range of analytical keys to make sense of these states and their role in the international scene
Going it alone? North Korea’s adaptability as a small power in a changing world
This article uses small states scholarship to map North Korea’s evolution from a post-colonial small state to a system-influencing state due to its nuclear weapons programme. The framework allows for contributions to: (1) The DPRK literature which in some parts has suggested the future collapse of the state, (2) The small states literature that suggests they can only survive if they integrate larger political and/or economic units, (3) The mainstream IR literature and its dominant realist streak that considers great powers and their will as the main drivers in contemporary world politics
Genomic Relationships, Novel Loci, and Pleiotropic Mechanisms across Eight Psychiatric Disorders
Genetic influences on psychiatric disorders transcend diagnostic boundaries, suggesting substantial pleiotropy of contributing loci. However, the nature and mechanisms of these pleiotropic effects remain unclear. We performed analyses of 232,964 cases and 494,162 controls from genome-wide studies of anorexia nervosa, attention-deficit/hyper-activity disorder, autism spectrum disorder, bipolar disorder, major depression, obsessive-compulsive disorder, schizophrenia, and Tourette syndrome. Genetic correlation analyses revealed a meaningful structure within the eight disorders, identifying three groups of inter-related disorders. Meta-analysis across these eight disorders detected 109 loci associated with at least two psychiatric disorders, including 23 loci with pleiotropic effects on four or more disorders and 11 loci with antagonistic effects on multiple disorders. The pleiotropic loci are located within genes that show heightened expression in the brain throughout the lifespan, beginning prenatally in the second trimester, and play prominent roles in neurodevelopmental processes. These findings have important implications for psychiatric nosology, drug development, and risk prediction.Peer reviewe
Dissecting the Shared Genetic Architecture of Suicide Attempt, Psychiatric Disorders, and Known Risk Factors
Background Suicide is a leading cause of death worldwide, and nonfatal suicide attempts, which occur far more frequently, are a major source of disability and social and economic burden. Both have substantial genetic etiology, which is partially shared and partially distinct from that of related psychiatric disorders. Methods We conducted a genome-wide association study (GWAS) of 29,782 suicide attempt (SA) cases and 519,961 controls in the International Suicide Genetics Consortium (ISGC). The GWAS of SA was conditioned on psychiatric disorders using GWAS summary statistics via multitrait-based conditional and joint analysis, to remove genetic effects on SA mediated by psychiatric disorders. We investigated the shared and divergent genetic architectures of SA, psychiatric disorders, and other known risk factors. Results Two loci reached genome-wide significance for SA: the major histocompatibility complex and an intergenic locus on chromosome 7, the latter of which remained associated with SA after conditioning on psychiatric disorders and replicated in an independent cohort from the Million Veteran Program. This locus has been implicated in risk-taking behavior, smoking, and insomnia. SA showed strong genetic correlation with psychiatric disorders, particularly major depression, and also with smoking, pain, risk-taking behavior, sleep disturbances, lower educational attainment, reproductive traits, lower socioeconomic status, and poorer general health. After conditioning on psychiatric disorders, the genetic correlations between SA and psychiatric disorders decreased, whereas those with nonpsychiatric traits remained largely unchanged. Conclusions Our results identify a risk locus that contributes more strongly to SA than other phenotypes and suggest a shared underlying biology between SA and known risk factors that is not mediated by psychiatric disorders.Peer reviewe
Prikrite in obstoječe male države
Small-state studies are fragmented into several disconnected streams of literature. This necessitates a more comprehensive perspective. Over the past two generations, small-state studies have gone through alternating trends, allassuming a small state in being. This article brings into view other streams of literature not based on this assumption. The existence of small states cannot be taken for granted. Small states tend to go through life cycles in which they are sometimes latent, sometimes actual. Once a small state has been formed, the need for political survival demands economic sustainability as well as a foundation of an identifying coherence. Challenges arise from globalisation and supranational integration, as well as from societal demands. The outcome may tend towards turbulence in some cases, stability in others. We are likely to understand these processes better in a historical, comparative perspective.Proučevanje malih državah je razdrobljeno. Obstaja nekaj nepovezanih tokov literature, ki zahtevajo bolj splošno perspektivo. V zadnjih dveh generacijah proučevanja malih držav je prišlo do alternativnih trendov, ki pa so vsi predpostavljali obstoj malih držav. Avtor izpostavlja druge tokove literature, ki temu ne slede. Obstoja malih držav torej ne moremo jemati za samoumevnega. Male države so nagnjene k prehajanju skozi življenjske cikle, v katerih so včasih prikrite, včasih obstoječe. Ko se mala država izoblikuje, potreba po političnem preživetju zahteva, da je gospodarsko vzdržljiva in da se njeni prebivalci z njo skladno poistovetijo. Izzivi za malo državo se pojavljajo med globalizacijo in nadnacionalnim združevanja, pa tudi zaradi zahtev (njene) družbe. V nekaterih primerih lahko izidi teh procesov vodijo k nestabilnosti, v drugih pa k stabilnosti. Gotovo bomo te procese bolje razumeli v zgodovinsko-primerjalni perspektivi
Transport interests and environmental regimes: The Baltic Sea transit of Russian oil exports
In the environmentally exposed Baltic Sea, a prolonged confrontation has set the transport interests of Russian crude oil against environmental interests, promoted by Russia's neighbours. During the 1990s all the Baltic littoral states - including Russia - collaborated well on marine environmental issues. When Russian oil exports accelerated after 1999, this environmental understanding broke down. Russian interests shifted as its oil income suddenly rose drastically. The confrontation peaked over a proposal to make the entire Baltic Sea into a particularly sensitive sea area (PSSA) under the International Maritime Organization (IMO). The proposal was adopted by the IMO in spite of Russian objections. The article shows how environmental interests trump transport interests in a manner that may not be sustainable. The case illustrates the need for environmental collaboration to be flexible in the face of shifting constellations of competing interests.Oil transport Marine environment IMO
IMO legislation and its implementation: Accident risk, vessel deficiencies and national administrative practices
The article takes as its point of departure the apparently contradictory findings in recent research about accident rates in shipping and IMO implementation records. It is argued here that although IMO conventions have probably greatly improved shipping safety, they cannot credibly be held to be the chief cause of reduced accident rates as claimed in a recent Marine Policy article, when the documented failures of flag state and port state implementation continue to leave vessels sailing with grave deficiencies. The present analysis posits and corroborates a cluster of linked tendencies that jointly undermine IMO implementation. The core problem is IMO’s weak connection to the national maritime administrations, leading to broadly discretionary practices, exacerbated by language difficulties. Adding new rules is no panacea, as new rules in some cases negatively affect the functioning of existing regulations, and sometimes seem motivated mainly to show political alertness. The structural weakness of the IMO/member state link is the core implementation problem that urgently needs to be dealt with if marine safety is to be improved. The concluding section proposes a reform to bring the IMO out of this conundrum and ensure effective implementation
IMO legislation and its implementation: Accident risk, vessel deficiencies and national administrative practices
The article takes as its point of departure the apparently contradictory findings in recent research about accident rates in shipping and IMO implementation records. It is argued here that although IMO conventions have probably greatly improved shipping safety, they cannot credibly be held to be the chief cause of reduced accident rates as claimed in a recent Marine Policy article, when the documented failures of flag state and port state implementation continue to leave vessels sailing with grave deficiencies. The present analysis posits and corroborates a cluster of linked tendencies that jointly undermine IMO implementation. The core problem is IMO's weak connection to the national maritime administrations, leading to broadly discretionary practices, exacerbated by language difficulties. Adding new rules is no panacea, as new rules in some cases negatively affect the functioning of existing regulations, and sometimes seem motivated mainly to show political alertness. The structural weakness of the IMO/member state link is the core implementation problem that urgently needs to be dealt with if marine safety is to be improved. The concluding section proposes a reform to bring the IMO out of this conundrum and ensure effective implementation.Shipping Maritime regulation Flag state Port state Detention Institutional interaction