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Self-disgust mediates the relationship between childhood adversities and psychosis
No full textObjective: Traumatic events in childhood have been implicated in the development of psychosis but, given that trauma is not in itself sufficient to cause psychosis, researchers have started to investigate other psychological constructs potentially involved in explaining this relationship. Given that self-disgust as a transdiagnostic construct plays a role in the development/maintenance of a range of mental health difficulties, the objective of this study was to investigate if self-disgust mediates the relationship between childhood trauma and psychosis. Method: A cross-sectional quantitative study design was used. Seventy-eight participants (Mage = 37.64 years, SDage = 11.57 years; 77% women; 88% White Caucasian) who reported experiencing clinical levels of psychosis were recruited using social media. The participants completed online survey measures of childhood trauma, self-disgust, experiences of psychosis, self-esteem, and external shame. The data were analysed using correlation and mediation analyses. Results: Significant indirect effects of childhood trauma on both positive (β = .17, BC 95% CI [.06, .30]) and negative symptoms (β = .26, BC 95% CI [.14, .40]) of psychosis via self-disgust were observed. These effects remained despite the inclusion of self-esteem and external shame as control variables in the mediation models. Conclusion: This study is the first to show a mediating role for self-disgust in the relationship between childhood trauma and later psychosis. Although the findings should be considered preliminary until strengthened by further research, they nevertheless provide corroboration of the potential utility of self-disgust as a transdiagnostic construct from a theoretical perspective, but also from its potential to inform formulation and interventions. <br/
A Novel Iterative Observer Approach for Real-Time Harmonic Estimation in Power Distribution Networks
No full textIn power distribution networks, the realization of online harmonic state estimation (HSE) puts forward a higher demand on the algorithm accuracy, stability as well as simplicity. To meet the requirements above, a novel iterative observer-based method for HSE is proposed. This method guarantees the stability of the harmonic estimation observer when output time delays are considered in the power distribution network. Meanwhile, signals with different frequencies can be estimated iteratively. System harmonics are regarded as the unknown exogenous disturbance, and each harmonic at multiple measurements is extracted and estimated iteratively. To guarantee the overall estimator stability, multiple transmission time delay is addressed in the system modelling for the design of observer gain. The proposed method achieves high estimation accuracy from multiple measurements while maintaining a low computation commitment. Comparing with traditional HSE methods, the iterative observer is capable of estimating the unexpected harmonics. The IEEE 13-bus power distribution system built in the Real Time Digital Simulator demonstrates the validity of the proposed method
The LOFAR Tied-Array All-Sky Survey:Timing of 21 pulsars including the first binary pulsar discovered with LOFAR
No full textWe report on the multi-frequency timing observations of 21 pulsars discovered in the LOFAR Tied-Array All-Sky Survey (LOTAAS). The timing data were taken at central frequencies of 149MHz (LOFAR) as well as 334 and 1532MHz (Lovell Telecope). The sample of pulsars includes 20 isolated pulsars and the first binary pulsar discovered by the survey, PSRJ1658+3630. We modelled the timing properties of the pulsars, which showed that they have, on average, larger characteristic ages.We present the pulse profiles of the pulsars across the three observing bands, where PSR J1643+1338 showed prole evolution that appears not to be well-described by the radius-to-frequency-mapping model. Furthermore, we modelled the spectra of the pulsars across the same observing bands, using a simple power law, and found an average spectral index of -1:9 ± 0:5. Amongst the pulsars studied here, PSRJ1657+3304 showed large flux density variations of a factor of 10 over 300 days, as well as mode changing and nulling on timescales of a few minutes. We modelled the rotational and orbital properties of PSR J1658+3630, which has a spin period of 33 ms in a binary orbit of 3.0 days with a companion of minimum mass of 0.87M, likely a Carbon-Oxygen or Oxygen-Neon-Magnesium type white dwarf. PSRJ1658+3630 has a dispersion measure of 3.0 pc cm-3, making it possibly one of the closest binary pulsars known
Silence of the Innocents: Undocumented Immigrants' Underreporting of Crime and their Victimization
No full textDo undocumented migrants underreport crimes to the police in order to avoid being deported? And do criminals exploit such vulnerability? We address these questions using victimization surveys and administrative data around the 1986 US immigration amnesty. The amnesty allows us to solve two major identification issues that have plagued this literature: migrants' legal status is endogenous and unobserved.The results show that the reporting rate of undocumented immigrants is 17 percent, which limits the immigrants ability to protect some of their fundamental human rights. However, right after the 1986 amnesty, which disproportionately legalized individuals of Hispanic origin, crime victims of Hispanic origin show enormous improvements in reporting behavior. The implied increase in the reporting rate by amnesty applicants is close to 20 percentage points
NanoSIMS Imaging and Analysis in Materials Science
No full textHigh-resolution SIMS analysis can be used to explore a wide range of problems in material science and engineering materials, especially when chemical imaging with good spatial resolution (50–100 nm) can be combined with efficient detection of light elements and precise separation of isotopes and isobaric species. Here, applications of the NanoSIMS instrument in the analysis of inorganic materials are reviewed, focusing on areas of current interest in the development of new materials and degradation mechanisms under service conditions. We have chosen examples illustrating NanoSIMS analysis of grain boundary segregation, chemical processes in cracking, and corrosion of nuclear components. An area where NanoSIMS analysis shows potential is in the localization of light elements, in particular, hydrogen and deuterium. Hydrogen embrittlement is a serious problem for industries where safety is critical, including aerospace, nuclear, and oil/gas, so it is imperative to know where in the microstructure hydrogen is located. By charging the metal with deuterium, to avoid uncertainty in the origin of the hydrogen, the microstructural features that can trap hydrogenic species, such as precipitates and grain and phase boundaries, can be determined by NanoSIMS analysis on a microstructurally relevant scale
A Study of Magnetic Relaxation in Dysprosium(III) Single-Molecule Magnets
No full textThough the development of single-molecule magnets (SMMs) is rapid, there are only two families of high energy barrier (Ueff) dysprosium(III) SMMs known so far: the cyclopentadienyl (Cp) family with sandwich structure and the pentagonal–bipyramidal (PB) family with D5h symmetry. These high barrier SMMs which usually possess Ueff > 500 cm-1 allow to separately study the four magnetic relaxation paths, namely the direct, quantum tunnelling, Raman and Orbach process, in detail. While the first family is chemically more challenging to modify the Cp rings we show here the latter family with the common formulae DyX1X2(Leq)5]+ can be readily fine tuned with a range of axial and equatorial ligands by simple substitution reactions, such as X1/X2 = -OCMe3 , -OSiMe3, -OPh, Cl- or Br-; Leq = THF/pyridine/4-methylpyridine. This allows to unambiguously reveal that the Ueff mainly depends on the identity of X1 and X2 rather than Leq. More importanty, the fitted parameters are barrier dependent. Where X1 is an O-donor and X2 is a halide we find 500 < Ueff < 600 cm-1; log[τ0 (s)]avg = -10.66 ± 0.93; log[C (s-1 K-n)]avg = 5.05 ± 0.70; navg = 4.1 ± 1.0; TH = 9 K (where τ0 is the pre-exponential factor for the Orbach relaxation process, C and n are parameters used to describe the Raman relaxation and TH is the highest temperature at which magnetic hysteresis is observed). For cases where both X1 and X2 are O-donors we find 900 < Ueff < 1300 cm-1; log[τ0 (s)]avg = -11.63 ± 0.57; log[C (s-1 K-n)]avg = 6.03 ± 0.52; navg = 4.1 ± 1.0; 18 < TH < 25 K. Based on this, we further conclude that Ueff not only has a linear correlation to the axial Dy-X bond lengths, but also to the TH for these PB SMMs. This represents the first systematic study of a family of lanthanide SMMs and derives the first magnetostructural correlation in Dy SMMs
Simulating the co-emergence of urban spatial structure and commute patterns in an African metropolis: a geospatial agent-based model
No full textUrban spatial structure and mobility patterns co-evolve. A fundamental process that underpins the emergent structure of cities and commuting patterns is location choice with respect to housing and employment. Consequently, location choice models constitute an important component of land use and transport interaction (LUTI) models and urban growth models. This paper documents the development and application of the Metropolitan Location and Mobility Patterns Simulator (METLOMP-SIM). METLOMP-SIM is an integrated geospatial and agent-based model that simulates how urban structure and travel patterns co-emerge, as a function of the location decisions of heterogeneous households and individuals within a heterogeneous, spatially-explicit urban context. After specifying a generic conceptual model that identifies the model’s structure, entities and agents’ decision-making framework, METLOMP-SIM is implemented using the Kumasi Metropolis in Ghana, West Africa as case study. Overall, the implemented model demonstrates that the encoded micro-scale behaviour of household and individual agents are able to mimic some macro-scale residential and job location patterns, and patterns of home-work trip production and attraction that closely match patterns in the case study metropolis, based on the available observational data. METLOMP-SIM responds to the some of the core limitations around model realism in previous agent-based urban location choice modelling efforts. The current model represents property and job market dynamics in both their ‘formal’ and ‘informal’ manifestations, making it sensitive and potentially relevant to urban land use model development and applications in Sub-Saharan African cities, and possibly in other developing countries
Full-Duplex Cooperative Non-Orthogonal Multiple Access System With Feasible Successive Interference Cancellation
No full textNon-orthogonal multiple access (NOMA) is a promising radio access scheme for future mobile networks due to its high spectral efficiency, but the weak user suffers poor performance due to the interference and poor channel quality. Full-duplex cooperative NOMA (FD C-NOMA) is an attractive solution by allowing the strong user to relay the weak user’s signal simultaneously, but most existingworks made an impractical assumption that the signals from the base station (BS) and the strong user can be perfectly resolved and combined at the weak user. Considering feasible successive interference cancellation (SIC) operation, we propose a two-phase FD C-NOMA system where the BS only transmits a new signal for the strong user in the second phase, such that the weak user can perform SIC to obtain its own signal. A sum-rate maximization for this proposedsystem is investigated and a low-complexity closed form solution is derived under the total BS transmission power and proportional rate constraints. Numerical simulation results show that the proposed FD C-NOMA system modelattains better sum-rate performance compared to other schemes
Viral breedings: HIV as pregnancy among bugchasers
No full textBugchasing is the fetishization of HIV among some gay men. Bugchasers, who thrive in online forums and social media, have generated complex subcultural narratives of the virus as a vehicle for intimacy, connection, and masculinity. While this practice has been addressed from public health and media studies, relatively little analysis has been conducted on their sex stories. In this article, I use the sex story 'Andy is HIV+' to explore how bugchasers appropriate the language of both HIV prevention and heterosexual reproduction to narrate new forms of vertical and horizontal kinship. These new forms are articulated through HIV infection: bugchasers 'breed' each other with their 'poz babies' and become 'brothers' and 'lovers.' While Dean (2009) has already discussed bugchasing kinship, I explore the practical implementation of these forms of relationality to address existing gaps in the literature. In the second part of this article, I also complicate existing research on bugchasing kinship by considering how the fictional nature of the materials under analyses problematizes our theoretical developments and our assumptions about the men producing the texts. In particular, I suggest that theoretical research on kinship should be accompanied by in-depth consideration of how fictional narratives translate into lived experience