bluuebunny/crossref_metadata_2025 huggingface dataset:
Regulation of insulin gene expression by overlapping DNA-binding elements
Authors: Nishimura Wataru , Salameh Therese , Kondo Takuma , Sharma Arun
Published: November 2005

The transcription factor MafA/RIPE3b1 is an important regulator of insulin gene expression. MafA binds to the insulin enhancer element RIPE3b (C1-A2), now designated as insulin MARE (Maf response element). The insulin MARE element shares an overlapping DNA-binding region with another insulin enhancer element A2. A2.2, a β-cell-specific activator, like the MARE-binding factor MafA, binds to the overlapping A2 element. Our previous results demonstrated that two nucleotides in the overlapping region are required for the binding of both factors. Surprisingly, instead of interfering with each other's binding activity, the MafA and the A2-binding factors co-operatively activated insulin gene expression. To understand the molecular mechanisms responsible for this functional co-operation, we have determined the nucleotides essential for the binding of the A2.2 factor. Using this information, we have constructed non-overlapping DNA-binding elements and their derivatives, and subsequently analysed the effect of these modifications on insulin gene expression. Our results demonstrate that the overlapping binding site is essential for maximal insulin gene expression. Furthermore, the overlapping organization is critical for MafA-mediated transcriptional activation, but has a minor effect on the activity of A2-binding factors. Interestingly, the binding affinities of both MafA and A2.2 to the overlapping or non-overlapping binding sites were not significantly different, implying that the overlapping binding organization may increase the activation potential of MafA by physical/functional interactions with A2-binding factors. Thus our results demonstrate a novel mechanism for the regulation of MafA activity, and in turn β-cell function, by altering expression and/or binding of the A2.2 factor. Our results further suggest that the major downstream targets of MafA will in addition to the MARE element have a binding site for the A2.2 factor.
The broad anti-viral agent glycyrrhizin directly modulates the fluidity of plasma membrane and HIV-1 envelope
Authors: Harada Shinji
Published: November 2005

Cell entry of enveloped viruses requires a wide-fusion-pore mechanism, involving clustering of fusion-activated proteins and fluidization of the plasma membrane and viral envelope. In the present study, GL (glycyrrhizin) is reported to lower membrane fluidity, thus suppressing infection by HIV, influenza A virus and vesicular stomatitis virus, but not by poliovirus. GL-treated HIV-1 particles showed reduced infectivity. GL also inhibited cell-to-cell fusion induced by HIV-1 and HTLV-I (human T-cell leukaemia virus type I). However, when cells treated with 1 mg/ml GL were placed in GL-free medium, they showed increased susceptibility to HIV-1 infection and HTLV-I fusion due to enhancement of membrane fluidity. The membrane dependence of GL and GL removal experiments suggest that GL does affect the cell entry of viruses. HIVs with more gp120 were less dependent on temperature and less sensitive to GL treatment than those with less gp120, indicating that the existence of more gp120 molecules resulted in a higher probability of forming a cluster of fusion-activated proteins.
A general treatment of deformation effects in Hamiltonians for inhomogeneous crystalline materials
Authors: Lassen B. , Willatzen M. , Melnik R. , Yan Voon L. C. Lew
Published: November 2005

In this paper, a general method of treating Hamiltonians of deformed nanoscale systems is proposed. This method is used to derive a second-order approximation both for the strong and weak formulations of the eigenvalue problem. The weak formulation is needed in order to allow deformations that have discontinuous first derivatives at interfaces between different materials. It is shown that, as long as the deformation is twice differentiable away from interfaces, the weak formulation is equivalent to the strong formulation with appropriate interface boundary conditions. It is also shown that, because the Jacobian of the deformation appears in the weak formulation, the approximations of the weak formulation is not equivalent to the approximations of the strong formulation with interface boundary conditions. The method is applied to two one-dimensional examples (a sinusoidal and a quantum-well potential) and one two-dimensional example (a freestanding quantum wire), where it is shown that the energy eigenvalues of the second-order approximations lie within 1% of the exact energy eigenvalues for a linear strain of up to 9.8%, whereas the first-order approximation has an error of less than 1% for a linear strain of up to 5.5%.
The effects of nonlocality on the evolution of higher order fluxes in nonequilibrium thermodynamics
Authors: Cimmelli V. A. , Ván P.
Published: November 2005

The role of gradient dependent constitutive spaces is investigated on the example of Extended Thermodynamics of rigid heat conductors. Different levels of nonlocality are developed and the different versions of extended thermodynamics are classified. The local form of the entropy density plays a crucial role in the investigations. The entropy inequality is solved under suitable constitutive assumptions. Balance form of evolution equations is obtained in special cases. Closure relations are derived on a phenomenological level.
A molecular-dynamics study of lipid bilayers: Effects of the hydrocarbon chain length on permeability
Authors: Sugii Taisuke , Takagi Shu , Matsumoto Yoichiro
Published: November 2005

In this paper, we investigate the effects of the hydrocarbon chain length of lipid molecules on the permeation process of small molecules through lipid bilayers. We perform molecular-dynamics simulations using three kinds of lipid molecules with different chain length: dilauroylphosphatidylcholine, dimyristoylphosphatidylcholine, and dipalmiltoylphosphatidylcholine. Free-energy profiles of O2, CO, NO, and water molecules are calculated by means of the cavity insertion Widom method and the probability ratio method. We show that the lipid membrane with longer chains has a larger and wider energy barrier. The local diffusion coefficients of water across the bilayers are also calculated by the force autocorrelation function method and the velocity autocorrelation function method. The local diffusion coefficients in the bilayers are not altered significantly by the chain length. We estimate the permeability coefficients of water across the three membranes according to the solubility-diffusion model; we find that the water permeability decreases modestly with increasing chain length of the lipid molecules.
Calculations of two-photon charge-transfer excitations using Coulomb-attenuated density-functional theory
Authors: Rudberg Elias , Sałek Paweł , Helgaker Trygve , Ågren Hans
Published: November 2005

In this work, we show that an implementation of Coulomb-attenuated density-functional theory leads to considerably better prospects than hitherto for modeling two-photon absorption cross sections for charge-transfer species. This functional, which corrects for the effect of poor asymptotic dependence of commonly used functionals, essentially brings down the widely different results for larger charge-transfer species between Hartree-Fock and density-functional theory (DFT)-B3LYP into a closer range. The Coulomb-attenuated functional, which retains the best aspects of the Hartree-Fock and DFT-B3LYP methods, proves to be very promising for further modeling design of multiphoton materials with technical applications.
Structure and electronic properties of highly charged C60 and C58 fullerenes
Authors: Díaz-Tendero Sergio , Alcamí Manuel , Martín Fernando
Published: November 2005

We present a theoretical study of the structure and electronic properties of positively charged C60q+ and C58q+ fullerenes (q=0–14). Electronic energies and optimum geometries have been obtained using density-functional theory with the B3LYP functional for exchange and correlation. We have found that closed- and semiclosed-shell C60q+ ions (q=0, 5, and 10) preserve the original icosahedral symmetry of neutral C60. For other charges, significant distortions have been obtained. The C58q+ fullerenes are, in general, less symmetric, being C588+ the closest to the spherical shape. Most C60q+ fullerenes follow Hund’s rule for spin multiplicity, while most C58q+ fullerenes are more stable with the lowest spin multiplicity. The calculated ionization potentials for both kinds of fullerenes increase almost linearly with charge, except in the vicinity of C6010+ and C588+. We have also explored the region of the potential-energy surface of C60q+ that leads to asymmetric fission. Minima and transition states corresponding to the last steps of the fission process have been obtained. This has led us to conclude that, for 3⩽q⩽8, C2+ emission is the preferred fragmentation channel, whereas, for higher q values, emission of two charged atomic fragments is more favorable. The corresponding fission barrier vanishes for q>14.
Electronic structure of phospho-olivines LixFePO4 (x=,1) from soft-x-ray-absorption and -emission spectroscopies
Authors: Augustsson A. , Zhuang G. V. , Butorin S. M. , Osorio-Guillén J. M. , Dong C. L. , Ahuja R. , Chang C. L. , Ross P. N. , Nordgren J. , Guo J.-H.
Published: November 2005

The electronic structure of the phospho-olivine LixFePO4 was studied using soft-x-ray-absorption (XAS) and emission spectroscopies. Characteristic changes in the valence and conduction bands are observed upon delithation of LiFePO4 into FePO4. In LiFePO4, the Fe-3d states are localized with little overlap with the O-2p states. Delithiation of LiFePO4 gives stronger hybridization between Fe-3d states and O-2p states leading to delocalization of the O-2p states. The Fe L-edge absorption spectra yield “fingerprints” of the different valence states of Fe in LiFePO4 and FePO4. Resonant soft-x-ray-emission spectroscopy at the Fe L edge shows strong contributions from resonant inelastic soft x-ray scattering (RIXS), which is described using an ionic picture of the Fe-3d states. Together the Fe L-edge XAS and RIXS study reveals a bonding character of the Fe 3d-O2p orbitals in FePO4 in contrast to a nonbonding character in LiFePO4.
Production of oxygen by electronically induced dissociations in ice
Authors: Johnson R. E. , Cooper P. D. , Quickenden T. I. , Grieves G. A. , Orlando T. M.
Published: November 2005

A solid-state chemical model is given for the production of O2 by electronic excitation of ice, a process that occurs on icy bodies in the outer solar system. Based on a review of the relevant available laboratory data, we propose that a trapped oxygen atom-water complex is the principal precursor for the formation of molecular oxygen in low-temperature ice at low fluences. Oxygen formation then occurs through direct excitation of this complex or by its reaction with a freshly produced, nonthermal O from an another excitation event. We describe a model for the latter process that includes competition with precursor destruction and the effect of sample structure. This allows us to put the ultraviolet photon, low-energy electron, and fast-ion experiments on a common footing for the first time. The formation of the trapped oxygen atom precursor is favored by the preferential loss of molecular hydrogen and is quenched by reactions with mobile H. The presence of impurity scavengers can limit the trapping of O, leading to the formation of oxygen-rich molecules in ice. Rate equations that include these reactions are given and integrated to obtain an analytic approximation for describing the experimental results on the production and loss of molecular oxygen from ice samples. In the proposed model, the loss rate varies, roughly, inversely with solid-state defect density at low temperatures, leading to a yield that increases with increasing temperature as observed. Cross sections obtained from fits of the model to laboratory data are evaluated in light of the proposed solid-state chemistry.
Adsorption of CO on the copper-precovered ZnO(0001) surface: A molecular-beam scattering study
Authors: Wang J. , Burghaus U.
Published: November 2005

Auger electron spectroscopy (AES), thermal-desorption spectroscopy (TDS), and, in particular, molecular-beam scattering techniques have been combined to address particle size effects in the adsorption of CO on Cu-on-ZnO(0001). AES and TDS lead to a Cu coverage, ΘCu, calibration. The TDS curves, as a function of ΘCu and CO exposure, revealed three structures at 150, 220, and 260–280K, in agreement with prior studies. However, a unique assignment of the TDS structures to a particular Cu face was not possible. An enhancement of the initial adsorption probability, S0, with respect to the support indicates the effect of the Cu nanoparticles. Despite that the shape of S0 versus impact energy curves was independent of ΘCu and agreed with Cu single-crystal reference systems, distinct particle size effects were present with regard to the adsorption mechanism. It was possible to observe a crossover from Langmuir-type adsorption dynamics to more precursor-assisted adsorption dynamics with increasing ΘCu. Thus, a dynamic structure-activity relationship was evident, i.e., the energy-transfer mechanism depends on the Cu morphology.
Low-frequency phonons in the point-contact spectrum of MgB2
Authors: Fisun V. V. , Triputen L. Yu. , Yanson I. K.
Published: November 2005

The second derivatives of the current-voltage characteristics of heterocontacts between a film of MgB2 and counterelectrodes of pure metals (Cu, Ag, Au, Be) are investigated by the method of point-contact (PC) spectroscopy. The PC spectra are studied in the normal (T⩾Tc) and superconducting (T<Tc) states along the direction of the c axis. In the normal state the spectra have a feature in the energy interval ∼20–30 mV in the form of a broad peak or a smeared kink. It is conjectured that the low-frequency modes of the phonon spectrum are also responsible for the high value of the superconducting transition temperature in MgB2. In the superconducting state the spectral features become N-shaped in the region of the low-frequency peak.
Suppression of the differential-tunnelling-conductance peak of a phase-coherent two-layer system by means of thermal fluctuations
Authors: Bezuglyĭ A. I.
Published: November 2005

A high, narrow, interlayer differential-tunnelling-conductance peak is observed at low temperatures in semiconductor heterostructures with two close-lying electron layers. This peak is the consequence of the interlayer phase coherence established in the system by Bose condensation of interlayer excitons, i.e., pairs of an electron and a hole belonging to the different layers. It is shown that increasing the temperature smoothes out the tunnelling-conductance peak by increasing the interlayer-voltage fluctuations. The temperature dependence obtained for the peak height agrees with experiment.
Predicting morphotropic phase boundary locations and transition temperatures in Pb- and Bi-based perovskite solid solutions from crystal chemical data and first-principles calculations
Authors: Grinberg Ilya , Suchomel Matthew R. , Davies Peter K. , Rappe Andrew M.
Published: November 2005

Using data obtained from first-principles calculations, we show that the position of the morphotropic phase boundary (MPB) and transition temperature at MPB in ferroelectric perovskite solutions can be predicted with quantitative accuracy from the properties of the constituent cations. We find that the mole fraction of PbTiO3 at MPB in Pb(B′B″)O3–PbTiO3, BiBO3–PbTiO3, and Bi(B′B″)O3–PbTiO3 exhibits a linear dependence on the ionic size (tolerance factor) and the ionic displacements of the B cations as found by density-functional-theory calculations. This dependence is due to competition between the local repulsion and A-cation displacement alignment interactions. Inclusion of first-principles displacement data also allows accurate prediction of transition temperatures at the MPB. The obtained structure-property correlations are used to predict morphotropic phase boundaries and transition temperatures in as yet unsynthesized solid solutions.
Inducing an antiferroelectric phase by segregating the layers of an intrinsically ferroelectric phase-only liquid crystal with linear-shaped molecules
Authors: Lee Ji-Hoon , Lim Tong-Kun
Published: November 2005

This paper demonstrates the possibility of inducing an antiferroelectric phase from an intrinsically ferroelectric phase-only liquid crystal by doping with linear-shaped molecules, thus separating the neighboring smectic layers of the ferroelectric liquid crystal from each other. Such an intrinsically impossible process is, in fact, shown to be quite possible due to its entropy-related origin. When the temperature of the doped cell is increased, the antiferroelectric phase reverts to the ferroelectric phase as the dopant molecules change position from interlayer space to intralayer space, a result that coincides with the sawtooth model suggested by Glaser and Clark [Phys. Rev. E 66, 021711 (2002)]. The macroscopic spontaneous polarization of the induced antiferroelectric phase (13.5nC∕cm2) is smaller than that of the ferroelectric phase (73.3nC∕cm2), which shows that the charge fluctuation is not the origin of the conversion.
dc leakage behavior in vanadium-doped bismuth titanate thin films
Authors: Chaudhuri Ayan Roy , Krupanidhi S. B.
Published: November 2005

The dc leakage current behavior and its thickness dependence in vanadium-doped bismuth titanate thin films have been investigated over a wide range of temperatures. The leakage current behavior was explained on the basis of space-charge-limited conduction theory. The current density, calculated from the I-V characteristics, was found to be 2.01×10−9A∕cm2 at an applied field of 2.9KV∕cm at room temperature. Three distinct regions were observed in the I-V plot which were attributed to the Ohmic region, trap-filled limit, and Child’s law. The influence of the film thickness on the dc leakage current conduction was found to be matching with that predicted by Lampert’s theory [Phys. Rev. 103, 1648 (1956)] of space-charge-limited conduction.
Characteristics of water-soluble polythiophene: TiO2 composite and its application in photovoltaics
Authors: Qiao Qiquan , Su Lianyong , Beck James , McLeskey James T.
Published: November 2005

We have studied the characteristics of composites of an environmentally friendly water-soluble polythiophene sodium poly[2-(3-thienyl)-ethoxy-4-butylsulfonate] (PTEBS) and TiO2. We observed that the ultraviolet-visible absorption spectrum of low molecular weight PTEBS is redshifted possibly due to the formation of aggregates. Cyclic voltammetry reveals the values of highest occupied molecular orbitals and lowest unoccupied molecular orbitals for PTEBS. A factor of 7 in photoluminescence quenching indicates that the exciton dissociation and charge separation occur successfully at the PTEBS:TiO2 (1:1 by weight) interface. This enhances the possibility that the separated charges will reach the electrodes before recombining. Scanning electron micrograph images show how the PTEBS and TiO2 are interconnected and form paths to the electrodes to improve charge transport. Photovoltaic devices with TiO2:PTEBS composite achieved an energy conversion efficiency of η=0.015%, a short circuit current of JSC=0.22mA∕cm2, an open circuit voltage of VOC=0.72V, and a fill factor of FF=0.29 under ∼300mW∕cm2 white light illumination.
Single-photon emission from a type-B InP∕GaInP quantum dot
Authors: Beirne G. J. , Michler P. , Jetter M. , Schweizer H.
Published: November 2005

Type-B InP∕GaInP quantum dots are expected to exhibit a type-II electronic structure. Evidence for this is provided by the variation in decay time of the ensemble as a function of excitation power density. Photon correlation measurements were subsequently performed on a single type-B InP∕GaInP quantum dot using a Hanbury-Brown and Twiss setup [Nature 178, 1447 (1956)]. Autocorrelation measurements were carried out under both continuous-wave and pulsed excitation conditions with single-photon emission observed in each case. The continuous-wave measurements display a pronounced antibunching dip at zero time delay while pulsed measurements enable the triggered generation of single photons on demand at a wavelength of approximately 750 nm.
Linear ion source with magnetron hollow cathode discharge
Authors: Tang D. L. , Pu S. H. , Wang L. S. , Qiu X. M. , Chu Paul K.
Published: November 2005

A linear ion source with magnetron hollow cathode discharge is described in this paper. The linear ion source is based on an anode layer thruster with closed-drift electrons that move in a closed path in the E×B fields. An open slit configuration is designed at the end of the ion source for the extraction of the linear ion beam produced by the magnetron hollow cathode discharge. The special configurations enable uninterrupted and expanded operation with oxygen as well as other reactive gases because of the absence of an electron source in the ion source. The ion current density and uniformity were experimentally evaluated. Using the ion source, surface modification was conducted on polyethylene terephthalate polymer films to improve the adhesion strength with ZnS coatings.
Fabrication of closely spaced, independently contacted electron-hole bilayers in GaAs-AlGaAs heterostructures
Authors: Keogh J. A. , Das Gupta K. , Beere H. E. , Ritchie D. A. , Pepper M.
Published: November 2005

We describe a technique to fabricate closely spaced electron-hole bilayers in GaAs-AlGaAs heterostructures. Our technique incorporates a method for making shallow contacts to a low density (<1011cm−2) two-dimensional electron gas (2DEG) that do not require annealing. Four terminal measurements on both layers (25nm apart) are possible. Measurements show a hole mobility μh>105cm2V−1s−1 and an electron mobility μe>106cm2V−1s−1 at 1.5K. Preliminary drag measurements made down to T=300mK indicate an enhancement of coulomb interaction over the values obtained from a static random phase approximation (RPA) calculation.
Imaging antiferromagnetic domains in GdNi2Ge2 with x-ray resonant magnetic scattering
Authors: Kim J. W. , Kreyssig A. , Tan L. , Wermeille D. , Bud’ko S. L. , Canfield P. C. , Goldman A. I.
Published: November 2005

We describe investigations of antiferromagnetic domains by resonant magnetic diffraction using linearly polarized x rays at the L2 edge of Gd in GdNi2Ge2. Studies of single domains and images of these domains provide details of the magnetic transition from a collinear antiferromagnetic structure for 16K<T<27.5K to a spiral structure for T<16K. This technique may be used to discriminate between antiferromagnetic domains that differ in their modulation or moment direction, and between the ordering of different magnetic species.
Preparation and Cyclization of Some N-(2,2-Dimethylpropargyl) Homo- and Heteroaromatic Amines and the Synthesis of Some Pyrido[2,3-d]pyrimidines
Authors: Holman Michelle A. , Williamson Natalie M. , Ward A. David
Published: November 2005

The Cu(i) catalyzed cyclization of o-substituted N-(2,2-dimethylpropargyl)anilines yields 8-substituted 2,2-dimethyl-1,2-dihydroquinolines, while m-substituted analogues provide a mixture of 5- and 7-substituted dihydroquinoline systems. This reaction can be extended to 2-amino-N-(2,2-dimethylpropargyl)anthracene, yielding a dihydronaphtho[2,3-f]quinoline product, and to aminoquinoline derivatives, which yield substituted phenanthroline products. Pyridine analogues did not cyclize, apparently because of complexation with the copper reagent.
An alternative synthetic approach to these cyclized products, when complexation may be a problem, is illustrated by the following example. 2-Chloro-4-N-(2,2-dimethylpropargyl)pyrimidine was reduced using a Lindlar catalyst to the corresponding alkene which did not undergo an amino-Claisen rearrangement. However, the 5-bromopyrimidine alkene analogue underwent addition with phenylselanyl bromide to give a product that cyclized, using butyllithium, to a pyrido[2,3-d]pyrimidine selenium-containing product from which the selenium moiety could be removed to yield either a dihydro- or a tetrahydro-pyrido[2,3-d]pyrimidine system. A Heck reaction on the 5-bromopyrimidine alkene gave a 5-methylene-6,7-dihydro-5H-pyrrolo[2,3-d]pyrimidine.
Mononuclear and Trinuclear Palladium(II) Complexes of Single- and Three-Ring Benzyl- or Xylyl-Substituted Cyclam Derivatives
Authors: Dong Ying , Lindoy Leonard F. , Turner Peter
Published: November 2005

A selection of 1 : 1 (palladium/ligand) complexes of cyclam derivatives incorporating from one to three N-benzyl groups has been synthesized. Related 3 : 1 species of two symmetrically branched, tri-cyclam species incorporating 1,3,5-‘tribenzyl’ or phloroglucinol cores are also reported. The X-ray crystal structures of the palladium complexes of two isomeric forms of the N,N′-dibenzylated (single-ring) macrocycle have been determined. In each complex the palladium ion occupies the N4-plane of the respective macrocycles in a square planar arrangement, with each complex cation adopting a stable trans-III configuration.
Genital injuries in women reporting sexual assault
Authors: Palmer Cheryn M. , McNulty Anna M. , D'Este Catherine , Donovan Basil
Published: November 2005

Background: The likelihood of genital injury following sexual assault remains unclear. Genital injury related to sexual assault is often an issue in court proceedings, with the expectation that injuries will be found in 'genuine' cases. Conviction rates are higher when the complainant has genital injuries. Objectives: To determine the type, frequency and severity of genital and non-genital injuries of women following alleged sexual assault and, in addition, to determine factors associated with the presence of injuries. Methods: The assault records and forensic examination findings of 153 consecutive women who attended a sexual assault service in Newcastle, Australia, between 1997 and 1999 were reviewed. All of the women were examined within 72 hours of the assault. Associations were sought between victim and reported assault variables and the presence of injury using multiple logistic regression analysis. Results: Of the women, 111 (73%) were aged under 30 years and only 4% were over 50 years. Penile–vaginal penetration was the most common type of sexual assault (86%). Non-genital injuries were found in 46% of the women examined (mostly minor) and genital injury in only 22%. Genital injury in the absence of non-genital injury was rare (3%). Independent risk factors for the detection of non-genital injuries were reported threats of violence (OR 5.7, 95% CI; 2.2–14.6). Risk factors for genital injury were the presence of non-genital injury (OR 19, 95% CI; 6.0–63.0), threats of violence (OR 3.7, 95% CI; 1.5–8.9) and being over the age of 40 years (OR 5.6, 95% CI; 1.6–20.3). If the alleged assailant was known to the woman this was protective for both non-genital (OR 0.3, 95% CI; 0.1–0.5) and genital (OR 0.4, 95% CI; 0.2–0.9) injury. Conclusions: The presence of genital injury should not be required to validate an allegation of sexual assault, particularly in the absence of non-genital injuries.
Mate Aaraikore A Muri Ake Nei: Experiences of Maori New Zealanders living with HIV
Authors: Grierson Jeffrey , Pitts Marian , Herewini Te Herekiekie , Rua'ine Geoff , Hughes Anthony J. , Saxton Peter J. W. , Whyte Matt , Misson Sebastian , Thomas Mark
Published: November 2005

Background: This paper is drawn from the first comprehensive study in New Zealand of the health and social experiences of HIV positive people and specifically addresses the experiences of HIV positive Maori. Methods: A total of 226 HIV positive men and women completed an anonymous, self-administered HIV Futures New Zealand questionnaire. Twenty-five Maori completed the survey (17 male, 7 female, 1 transgendered). The majority identified as takataapui (Maori and homosexual) five were heterosexual women, and four identified with other sexualities. Results: Seven respondents indicated that they had received pre-test counselling, and 18 that they had received post-test counselling. The mean CD4 count at most recent test was 462.4 cells/µL. The mean HIV viral load result at most recent test was 558.1 copies/mL. Two-thirds of respondents were currently using antiretroviral treatments, and half had taken a break from them. The most commonly cited source of social support was their doctor. Eight respondents were in full-time work; most received benefits or a pension as their main income source; five were living below the poverty line. Only two respondents did not personally know another person with HIV. All had disclosed their status to someone; fifteen said that unwanted disclosure had occurred. Eight reported experiencing discrimination concerning accommodation, nine in a medical setting and seven in relation to employment. Conclusions: Maori people in New Zealand have access to a comprehensive health care system, nonetheless it is of concern that a number report discrimination and unwanted disclosure of their HIV status, most particularly within health care settings.
A study of commercial sex and HIV/STI-related risk factors among hospitality girls in entertainment establishments in Wuhan, China
Authors: Wei Shan-Bo , Chen Zhong-Dan , Zhou Wang , Wu Feng-Bo , Li Si-Ping , Shan Jian-Guo
Published: November 2005

Background: Commercial sex is illegal in China but there are still many hospitality girls (HGs) working at licenced entertainment establishments in many places in the country. Hospitality girls can be categorised as sex-HGs and non-sex-HGs. Objective: To understand the proportion of sex-HGs and non-sex-HGs, the prevalence of HIV and sexually transmitted infections, and the high-risk behaviours among HGs. Methods: A total of 257 HGs at 29 entertainment establishments (13 sauna/massage parlors, 10 dancing/karaoke bars and six barbershops) from seven urban districts in Wuhan were investigated and studied with a two-step sampling frame during November and December 1999. Information on sexual practices, drug abuse, condom use and other related factors were collected by anonymous interviewer-administered questionnaires. Anonymous laboratory testing was performed on 185 (72%) serum samples obtained for HIV-1 and HSV-2 by enzyme-linked immunosorbent assay. Results: Of the 257 HGs, the mean age was 22.7 years (range 16–36 years); 147 (57.2%) stated they were sex-HGs, 15 (5.8%) were drug users, of whom 12 (80%) were injecting and 3 (20%) were inhaling. Sex-HGs was significantly correlated with drug abuse (P < 0.01, OR = 11.47). Among the 147 sex-HGs, 29 (19.7%) had sex with male clients more than seven times per week, 76 (51.7%) claimed to have used condoms consistently. The sero-prevalence survey of 185 HGs revealed that none tested HIV seropositive, and 40 (21.6%) were HSV-2 seropositive, which was positively correlated with sex-HGs (P < 0.01, OR = 3.13). Conclusions: Although the HIV epidemic in Wuhan has not yet reached a high level, HIV/AIDS prevention and control must be taken into account in entertainment establishments because of the existing high risk-taking behaviours and high STI incidence among HGs. It is feasible to carry out epidemiological investigations, which are concerned with sensitive topics such as sex, drug abuse, etc, among community-based female sex workers if designed and implemented prudently.
Epidemiology of HIV and sexually transmitted infections in China
Authors: Zhang Kong-Lai , Ma Shao-jun , Xia Dong-yan
Published: November 2005

As the most populous country in the world, China has been confronted with the huge challenges that HIV and sexually transmitted infections pose. The HIV infection rate among adults is lower than 0.1%, however, the estimated number of HIV infections sits around one million, according to the estimation of some experts. HIV infection is highly prevalent in some regional areas of China and the incidence rate of sexually transmitted infections has sharply increased since the 1980s. The number of HIV infections may reach 10 million if no effective measures are taken. This article aims to outline the profile of the epidemic in China as well as to elaborate on the contributing factors and the response of the government and community.
An unusual cause of pelvic inflammatory disease due to Neisseria meningitidis
Authors: Alajeel Ayad A. Said , Garland Suzanne M.
Published: November 2005

A case of pelvic inflammatory disease due to Neisseria meningitidis is described. The importance of the definitive diagnosis of Neisseria to a species level is underscored for public health issues, appropriate contact tracing, as well as potential psychosocial implications. A review of the literature of genitally related N. meningitidis cases is made.
Correlates of having unprotected vaginal sex among detained adolescent females: an exploratory study of sexual factors
Authors: Crosby Richard , Salazar Laura F. , DiClemente Ralph J. , Yarber William L.
Published: November 2005

Background: Erotophilia, motivations for engaging in sex, and pleasure-related barriers to using condoms may all be important determinants of whether high-risk adolescent females have sex unprotected by a condom. This exploratory study identified associations between these factors and engaging in unprotected vaginal sex (UVS) among a sample of adolescent females recruited from short-term detention facilities in the USA. Methods: A cross-sectional survey of 211 adolescent females (14–18 years of age) was conducted. Only those indicating they had sex within the past 2 months were included in the analysis. Adolescents were recruited within eight detention facilities. Measures were assessed using audio-computer assisted self-interviewing (A-CASI). Results: In race-adjusted analyses, adolescents indicating greater pleasure-associated barriers to using condoms were more than 4.3 times more likely than those indicating fewer barriers to report having UVS in the past 2 months (AOR = 4.36; 95% CI = 2.15–8.86). Similarly, those scoring higher in erotophilia (compared with those scoring lower) were more than twice as likely to report UVS (AOR = 2.08; 95% CI = 1.02–4.24). Finally, adolescents who had ever been pregnant were ∼2.5 times more likely to report having recent UVS (AOR = 2.48; 95% CI = 1.1–5.34). With the exception of having five or more sex partners in the past 2 months (P = 0.08), none of the remaining correlates approached multivariate significance. Conclusions: Constructs such as erotophilia and pleasure-related barriers to condom use may be important correlates of UVS among this population of high-risk adolescents.
The evolution of sexual health nursing in Australia: a literature review
Authors: O'Keefe E. J.
Published: November 2005

Background: The purpose of this paper is to describe and encapsulate the elements of the sexual health nurse’s role in Australia. In Australia, sexual health nursing is a fast evolving speciality operating within a climate of diverse role expectations, settings and population groups. Today’s health care climate demands that nurses’ roles and their impact on patient care be held up to scrutiny. Methods: A literature review was conducted that used descriptive analysis to elicit the recurrent themes appearing in the Australian sexual health nursing literature that would describe the role. Results: A model of sexual health nursing was evident with the two primary themes of professional responsibility and patient care. The professional role included a philosophy of sharing nursing experiences, collaboration, employment in multiple settings, and the development of the role into advanced practice, appropriate academic and clinical preparation and a commitment to research. The patient care role included the provision of individual and holistic patient care, ability to access specific at-risk groups, clinical effectiveness, patient education and community development roles. Conclusion: Australian sexual health nurses make a specific and measurable contribution to the health care system. They are likely to continue to advance their role supported by appropriate research that validates their models of practice, continues their philosophy of sharing their experiences and that documents the impact they have on the health outcomes of individuals and populations.
Mitochondrial toxicity of nucleoside analogues: mechanism, monitoring and management
Authors: Cherry Catherine L. , Lal Luxshimi , Wesselingh Steven L.
Published: November 2005

Nucleoside analogues (NRTIs) are potent antiretroviral medications and are central to effective highly active antiretroviral therapy (HAART). Their intended action is to inhibit HIV reverse transcriptase. Nucleoside analogues also inhibit replication of mitochondrial DNA, and the pathogenesis of many of the toxicities associated with HAART is thought to be NRTI-induced mitochondrial dysfunction. Individuals with HIV infection may be particularly susceptible to clinically significant mitochondrial toxicity due to possible effects of HIV itself on mitochondria. At present there is no reliable method of detecting subclinical mitochondrial toxicity in patients exposed to NRTIs. Clinical awareness of this problem is therefore important to ensure the early detection of significant side effects and to allow timely consideration of changing therapy in those affected. There is no proven, effective therapy for NRTI-associated mitochondrial toxicity other than ceasing the implicated agent, and even with this strategy, resolution of symptoms may be incomplete. Similarly, there are no established methods for preventing mitochondrial toxicity in those on therapy including NRTIs. Micronutrients may have a role, but further study is needed to clarify optimal prevention as well as monitoring strategies.
Men, bodily change and urethritis: a qualitative study
Authors: Pitts M. K. , Smith A. M. A , Mischewski A. , Fairley C.
Published: November 2005

Objectives: To describe how men narrate the process of bodily change as a trigger to presentation for a suspected sexually transmissible infection. Methods: The study was qualitative with 18 men presenting at a specialist sexual health centre in an urban setting. Results: All men gave narratives that included accounts of bodily changes prior to presentation. The nature, severity and persistence of those changes were unrelated to subsequent diagnosis. Men responded particularly to visual changes as cues to action. Conclusions: The men exhibited limited skills in understanding the significance and the specifics of bodily change as they may relate to a sexually transmissible infection. While these men identified a broad range of changes as potentially indicative of a sexually transmissible infection, their ability to act on visceral rather than visual cues appears constrained in that they were less able to respond to the feel of their body than the way that it looked.
Predictors for non-adherence to antiretroviral therapy
Authors: Wilson K. J. , Doxanakis A. , Fairley C. K.
Published: November 2005

Objectives: To determine the risk factors for non-adherence to antiretroviral therapy. Methods: Two hundred clients attending the Melbourne Sexual Health Centre completed a questionnaire about lifestyle, self-efficacy, depression, drug or alcohol use, social supports, and attitudes to health care. Self-reported adherence (SRA) was measured by missed doses in the last 4, 7 and 28 days. Routinely collected viral load levels were reviewed. Results: Two hundred (85%) out of 231 eligible clients participated in the study. Viral load was most strongly associated with SRA for the last 28 days (P < 0.001). Non-adherence was defined as <98.2% SRA. Non-adherence was most strongly associated with having regular daily routines [odds ratio and 95% confidence interval = 0.4 (0.2, 0.7], having set times for getting up and going to bed [0.5 (0.3, 1.0)], using marijuana more than 4 times per week [0.4 (0.2, 1.0)] and lower self-efficacy which included; being sure that you will be able to take medications as directed [0.2 (0.1, 0.6)] and being sure that missing doses of HIV medication will result in drug resistance [0.4 (0.2, 0.7)]. When significant questions were combined into a composite score to screen for non-adherence, the sensitivity to predict non-adherence was as high as 71% with a specificity of 59%. Conclusions : This study showed that a 10-min questionnaire was associated with clients past non-adherence to antiretroviral therapy and may be useful for predicting future adherence.
HIV-1 co-infection, superinfection and recombination
Authors: Steain Megan C. , Wang Bin , Dwyer Dominic E. , Saksena Nitin K.
Published: November 2005

ABSTRACT. As the human immunodeficiency virus (HIV) pandemic progresses, an increasing number of recombinant viruses have been identified and in many geographical regions they are now the predominating strain. These recombinants are formed when an individual has acquired a co-infection or superinfection with more than one HIV-1 strain or subtype. Thus, dually infected individuals provide opportunities for studying HIV recombinants and viral interactions between infecting strains in vivo. The possible epidemiological, clinical and therapeutic implications of dual infections and recombination are many. Recombination may result in the emergence of more pathogenic and virulent HIV strains with altered fitness, tropism, and resistance to multiple drugs, and may hamper the development of subtype-based vaccines. This review is aimed at providing a more thorough understanding of dual infections (both co-infection and super-infection) and the possible consequences of the emergence of recombinant HIV-1 strains.
The concordance of Chlamydia trachomatis genital infection between sexual partners, in the era of nucleic acid testing
Authors: Markos A. R.
Published: November 2005

Introduction: The rate of transmission of Chlamydia trachomatis, by infected males and females to their sexual partners, has been a matter of continued scientific interest and exploration. Methods: We examined the correlation of C. trachomatis infection in sexual partnerships, using Strand Displacement Amplification. Results: During July–November 2003, 97 male patients were reported positive for C. trachomatis. Fifty of the female sexual consorts were amenable for contact tracing, 38 of whom were identified as C. trachomatis positive. Within the same period, 93 female patients were C. trachomatis positive, and 56 male consorts were traceable, of whom 43 were positive for C. trachomatis. Conclusions: The concordance of C. trachomatis between sexual partners is in the region of 75%. This strengthens the case for epidemiological treatment for all consorts.
Risk factors for HIV infection in a gynaeco - obstetric population in Vietnam — a case-control study
Authors: Tran Thi Thu Ha , Mulhall Brian P. , Macaskill Petra , Nguyen Thanh Quang
Published: November 2005

Background: Vietnam has an emerging HIV epidemic, particularly in male drug injectors. Data on HIV infections in women in the general population, and their risk factors, are scanty. Methods: A case-control study was performed in a large gynaeco–obstetric hospital in Haiphong city in 1998–2001. The sample was 22000 attendees. The medical records of 58 HIV-seropositive cases were compared with 422 randomly chosen HIV-seronegative controls for potential risk factors. Results: A multivariate analysis found that HIV infection was associated with young age, past/current history of sexually transmitted infections (STI) and being unemployed. Patients aged 21–30 years were 10-fold less likely to be infected than women aged <20 years (OR 0.11, 95%CI 0.04–0.33). Women with a past/current history of STI had over 20 times the risk of those who did not (95% CI 6.7–62.3). Unemployed women had at least twice the risk of infection of any other occupational group. Conclusions: We have identified risk factors in women that have not been highlighted previously in Vietnam. Our study suggests that all antenatal women, especially those who are young or unemployed (or, with a current/past history of STI), should be offered free HIV tests, counselling and management.
Bangkok: The End of Broken Promises? XV International AIDS Conference, 2004
Authors: Stefanski Daniel A.
Published: November 2005

The global community has gain failed to significantly confront the AIDS crisis. In the context of a worsening HIV pandemic, the conference highlighted the shortfall in funding, the soaring infection rate in Asia, the need to integrate prevention and treatment and the difficulties in coordinating a global response. To overcome AIDS, the global community must put aside ideology and honour its commitments.
Socio-demographic and behavioural factors associated with high incidence of sexually transmitted infections in female sex workers in Madagascar following presumptive therapy
Authors: Behets Frieda M-T. , Van Damme Kathleen , Rasamindrakotroka Andry , Hobbs Marcia , McClamroch Kristi , Rasolofomanana Justin Ranjalahy , Raharimalala Leonardine , Dallabetta Gina , Andriamiadana Jocelyne
Published: November 2005

Background: Too little is known about the many women who generate income in Madagascar by trading sex. Methods: Clinical and laboratory exams were offered to 493 non-care seeking female sex workers (SWs) in Antananarivo and 493 in Tamatave. SWs were recruited by peers in their community; they were interviewed, counselled and treated for sexually transmitted infections (STIs) at recruitment and re-evaluated 2 months later. Results: One hundred and eighty six (38%) of the SWs in Antananarivo and 113 (23%) in Tamatave did not complete primary school (P < 0.0001). The incidence rates per person per month in Antananarivo and Tamatave, respectively, were 0.09 and 0.08 for gonorrhoea; 0.05 and 0.03 for chlamydia; 0.24 and 0.15 for trichomoniasis; 0.07 and 0.05 for syphilis. At follow-up, consistent condom use with clients was reported by 56 (12%) SWs in Antananarivo and 137 (29%) in Tamatave (P < 0.0001); 320 (70%) SWs in Antananarivo and 11 (2%) in Tamatave reported sex with a non-paying partner in the past month (P < 0.0001). In Antananarivo, 422 (92%) of the SWs thought they were at no or low risk of having an STI compared to 100 (21%) in Tamatave (P = 0.02). At follow-up, 277 (61%) SWs reported no birth control for their last sex act in Antananarivo, compared to 26 (5%) in Tamatave (P < 0.0001). Socio-demographic and behavioural risk factors for incident gonorrhoea, chlamydia and trichomoniasis varied by city. Conclusions: Strategies to address the needs of women who trade sex should include educational and economic opportunities; should tackle male partners of SWs; promote dual protection against unintended pregnancy and STIs, while taking into account local socio-demographic and behavioural characteristics.
Sex work and the law
Authors: Harcourt Christine , Egger Sandra , Donovan Basil
Published: November 2005

We reviewed publications, websites, and field observations to explore the health and welfare impacts and administrative effectiveness of different legal approaches to sex work. We identified three broad legal approaches: (1) prohibition, including the unique Swedish law criminalising sex workers’ clients; (2) licensing; and (3) decriminalisation. Each of these models is employed under one or more jurisdictions in Australia. We make preliminary observations on their consequences and conclude that, on initial impression, decriminalisation may offer the best outcomes. However, more rigorous population-based research is needed to properly assess the health and welfare impacts of legal approaches to sex work.