Intoxication, criminal offences and suicide attempts in a group of South African problem drinkers

Background. Incidence rates of crime and alcohol abuse in South Africa are unacceptably high. Research suggests a relationship between alcohol and both crime and suicide. This study aims to add to the information base on this topic in South Africa.Methods. This is a cross-sectional record study of criminal offences and suicide attempts in 269 admissions to an alcohol rehabilitation unit in the Western Cape. Types of criminal offences and suicide attempts are described. Relationships are sought between crime, violent crime and suicide attempts on the one hand, and demographic and alcohol-related variables on the other.Results. One hundred and four subjects (39%) had criminal convictions, the majority of which were committed while the subjects were intoxicated. The commonest alcoholrelated crimes were driving-related (17% of subjects) and crimes of violence (15%). Male gender, younger age at initiation of drinking, and earlier onset of problem drinking were significantly associated with criminal behaviour. Violent crime was associated with earlier onset of initial, regular and problem drinking, and maternal alcohol abuse. Suicide attempts (24% of subjects) were associated with female gender, white racial group, not being in a marital relationship, younger current age and early age of problem drinking.Conclusions. There was an association between intoxication and both violent crime and suicide attempts. The importance of population studies and the need for intervention programmes aimed at teenagers who are drinking, are emphasised

Evidence that human and equine erythrocytes could have significant roles in the transport and delivery of amino acids to organs and tissues

Erythrocytes have a well-defined role in the gaseous exchange of oxygen and carbon dioxide in the mammalian body. The erythrocytes can contain more than half of the free amino acids present in whole blood. Based on measures showing that venous erythrocyte levels of amino acids are much less than arterial erythrocyte levels, it has previously been proposed that erythrocytes also play a role in the delivery of amino acids to tissues in the body. This role has been dismissed because it has been assumed that to act as an amino acid transport vehicle, the erythrocytes should release their entire amino acid content in the capillary beds at the target tissues with kinetic studies showing that this would take too long to achieve. This investigation set out to investigate whether the equine erythrocytes could rapidly take up and release smaller packages of amino acids when exposed to high or low external concentrations of amino acids, because it seemed very unlikely that cells would be able to release all of their amino acids without serious impacts on osmotic balance. Freshly prepared erythrocytes were placed in alternating solutions of high and low amino acid concentrations in PBS to assess the capacities of these cells to rapidly take up and release amino acids depending on the nature of the external environment. It was found that amino acids were rapidly taken up and released in small quantities in each cycle representing 15% of their total load in equine erythrocytes and 16% in human erythrocytes. The capacity for rapid uptake/release of amino acids by equine and human erythrocytes provided evidence to support the theory that mammalian erythrocytes have a significant role in transport of amino acids from the liver to tissues, muscles and organs

Automatic estimation of harmonic tension by distributed representation of chords

The buildup and release of a sense of tension is one of the most essential aspects of the process of listening to music. A veridical computational model of perceived musical tension would be an important ingredient for many music informatics applications. The present paper presents a new approach to modelling harmonic tension based on a distributed representation of chords. The starting hypothesis is that harmonic tension as perceived by human listeners is related, among other things, to the expectedness of harmonic units (chords) in their local harmonic context. We train a word2vec-type neural network to learn a vector space that captures contextual similarity and expectedness, and define a quantitative measure of harmonic tension on top of this. To assess the veridicality of the model, we compare its outputs on a number of well-defined chord classes and cadential contexts to results from pertinent empirical studies in music psychology. Statistical analysis shows that the model's predictions conform very well with empirical evidence obtained from human listeners.Comment: 12 pages, 4 figures. To appear in Proceedings of the 13th International Symposium on Computer Music Multidisciplinary Research (CMMR), Porto, Portuga

Leigh-Strassler compactified on a spindle

We construct a new class of supersymmetric AdS3 × Y7 solutions of type IIB supergravity, where Y7 is an S5 fibration over a spindle, which are dual to d = 2, N = (0, 2) SCFTs. The solutions are constructed in a sub-truncation of D = 5, SO(6) maximal gauged supergravity and they all lie within the anti-twist class. We show that the central charge computed from the gravity solutions agrees with an anomaly polynomial calculation associated with compactifying the N = 1, d = 4 Leigh-Strassler SCFT on a spindle

Low temperature properties of holographic condensates

In the current work we study various models of holographic superconductors at low temperature. Generically the zero temperature limit of those models are solitonic solution with a zero sized horizon. Here we generalized simple version of those zero temperature solutions to small but non-zero temperature T. We confine ourselves to cases where near horizon geometry is AdS^4. At a non-zero temperature a small horizon would form deep inside this AdS^4 which does not disturb the UV physics. The resulting geometry may be matched with the zero temperature solution at an intermediate length scale. We understand this matching from separation of scales by setting up a perturbative expansion in gauge potential. We have a better analytic control in abelian case and quantities may be expressed in terms of hypergeometric function. From this we calculate low temperature behavior of various quatities like entropy, charge density and specific heat etc. We also calculate various energy gaps associated with p-wave holographic superconductor to understand the underlying pairing mechanism. The result deviates significantly from the corresponding weak coupling BCS counterpart.Comment: 17 Page

Emergent Gauge Fields in Holographic Superconductors

Holographic superconductors have been studied so far in the absence of dynamical electromagnetic fields, namely in the limit in which they coincide with holographic superfluids. It is possible, however, to introduce dynamical gauge fields if a Neumann-type boundary condition is imposed on the AdS-boundary. In 3+1 dimensions, the dual theory is a 2+1 dimensional CFT whose spectrum contains a massless gauge field, signaling the emergence of a gauge symmetry. We study the impact of a dynamical gauge field in vortex configurations where it is known to significantly affect the energetics and phase transitions. We calculate the critical magnetic fields H_c1 and H_c2, obtaining that holographic superconductors are of Type II (H_c1 < H_c2). We extend the study to 4+1 dimensions where the gauge field does not appear as an emergent phenomena, but can be introduced, by a proper renormalization, as an external dynamical field. We also compare our predictions with those arising from a Ginzburg-Landau theory and identify the generic properties of Abrikosov vortices in holographic models.Comment: 19 pages, 14 figures, few comments added, version published in JHE

The structure of the PapD-PapGII pilin complex reveals an open and flexible P5 pocket

P pili are hairlike polymeric structures that mediate binding of uropathogenic Escherichia coli to the surface of the kidney via the PapG adhesin at their tips. PapG is composed of two domains: a lectin domain at the tip of the pilus followed by a pilin domain that comprises the initial polymerizing subunit of the 1,000-plus-subunit heteropolymeric pilus fiber. Prior to assembly, periplasmic pilin domains bind to a chaperone, PapD. PapD mediates donor strand complementation, in which a beta strand of PapD temporarily completes the pilin domain's fold, preventing premature, nonproductive interactions with other pilin subunits and facilitating subunit folding. Chaperone-subunit complexes are delivered to the outer membrane usher where donor strand exchange (DSE) replaces PapD's donated beta strand with an amino-terminal extension on the next incoming pilin subunit. This occurs via a zip-in-zip-out mechanism that initiates at a relatively accessible hydrophobic space termed the P5 pocket on the terminally incorporated pilus subunit. Here, we solve the structure of PapD in complex with the pilin domain of isoform II of PapG (PapGIIp). Our data revealed that PapGIIp adopts an immunoglobulin fold with a missing seventh strand, complemented in parallel by the G1 PapD strand, typical of pilin subunits. Comparisons with other chaperone-pilin complexes indicated that the interactive surfaces are highly conserved. Interestingly, the PapGIIp P5 pocket was in an open conformation, which, as molecular dynamics simulations revealed, switches between an open and a closed conformation due to the flexibility of the surrounding loops. Our study reveals the structural details of the DSE mechanism

Holographic Superconductors from Einstein-Maxwell-Dilaton Gravity

We construct holographic superconductors from Einstein-Maxwell-dilaton gravity in 3+1 dimensions with two adjustable couplings $\alpha$ and the charge $q$ carried by the scalar field. For the values of $\alpha$ and $q$ we consider, there is always a critical temperature at which a second order phase transition occurs between a hairy black hole and the AdS RN black hole in the canonical ensemble, which can be identified with the superconducting phase transition of the dual field theory. We calculate the electric conductivity of the dual superconductor and find that for the values of $\alpha$ and $q$ where $\alpha/q$ is small the dual superconductor has similar properties to the minimal model, while for the values of $\alpha$ and $q$ where $\alpha/q$ is large enough, the electric conductivity of the dual superconductor exhibits novel properties at low frequencies where it shows a "Drude Peak" in the real part of the conductivity.Comment: 25 pages, 13 figures; v2, typos corrected; v3, refs added, to appear in JHE