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Repeat rectal chlamydia infection is common in men who have sex with men (MSM) following treatment with 1 g azithromycin. This study describes the association between organism load and repeat rectal chlamydia infection, genovar distribution, and efficacy of azithromycin in asymptomatic MSM. Stored rectal chlamydia-positive samples from MSM were analysed for organism load and genotyped to assist differentiation between reinfection and treatment failure. Included men had follow-up tests within 100 days of index infection. Lymphogranuloma venereum and proctitis diagnosed symptomatically were excluded. Factors associated with repeat infection, treatment failure and reinfection were investigated. In total, 227 MSM were included – 64 with repeat infections [28·2%, 95% confidence interval (CI) 22·4–34·5]. Repeat positivity was associated with increased pre-treatment organism load [odds ratio (OR) 1·7, 95% CI 1·4–2·2]. Of 64 repeat infections, 29 (12·8%, 95% CI 8·7–17·8) were treatment failures and 35 (15·4%, 95% CI 11·0–20·8) were reinfections, 11 (17·2%, 95% CI 8·9–28·7) of which were definite reinfections. Treatment failure and reinfection were both associated with increased load (OR 2·0, 95% CI 1·4–2·7 and 1·6, 95% CI 1·2–2·2, respectively). The most prevalent genovars were G, D and J. Treatment efficacy for 1 g azithromycin was 83·6% (95% CI 77·2–88·8). Repeat positivity was associated with high pre-treatment organism load. Randomized controlled trials are urgently needed to evaluate azithromycin's efficacy and whether extended doses can overcome rectal infections with high organism load.
Few studies have investigated the impact of lifestyle interventions during pregnancy on post-partum weight retention and infant growth. Thirty seven previously non-exercising, overweight or obese pregnant women were randomly assigned to a walking intervention or non-intervention control. For the follow-up study, weight of the mother and weight, length and body composition of the infant were collected at 1 month post-partum (n=37) and 6 months post-partum (n=33). Analysis of variance and linear regression were conducted to determine the differences and association in maternal post-partum weight retention and child outcomes. At 6 months post-partum, weight retention of obese women in the intervention group (Int-OB) was −0.10±8.11 kg; while, obese women in the control group (Con-OB) was 6.35±7.47 kg. A significantly higher percentage of Con-OB women retained more than 5 kg at 6 months post-partum (P=0.046). Even though statistically non-significant between the groups, the growth trend observed among offspring of obese women in the control group was consistently higher than the offspring of obese women in the intervention group from birth to 6-months. Third trimester gestational weight gain rate significantly predicted 6-m weight-for-length z-score after controlling for birth weight, treatment group and pre-pregnancy body mass index (r2=0.31, β=1.75, P=0.03). The reduced post-partum weight retention observed among the obese women in the intervention group may be explained in part by the lifestyle modification during pregnancy.
Convergent studies provide support for abnormalities in the structure and functioning of the prefrontal cortex (PFC) and the amygdala, the key components of the neural system that subserves emotional processing in major depressive disorder (MDD). We used resting-state functional magnetic resonance imaging (fMRI) to examine potential amygdala–PFC functional connectivity abnormalities in treatment-naive subjects with MDD.
Resting-state fMRI data were acquired from 28 individuals with MDD and 30 healthy control (HC) subjects. Amygdala–PFC functional connectivity was compared between the MDD and HC groups.
Decreased functional connectivity to the left ventral PFC (VPFC) from the left and right amygdala was observed in the MDD group, compared with the HC group (p < 0.05, corrected).
The treatment-naive subjects with MDD showed decreased functional connectivity from the amygdala to the VPFC, especially to the left VPFC. This suggests that these connections may play an important role in the neuropathophysiology of MDD at its onset.
We report on Chandra observations of the black widow pulsar, PSR B1957+20. Evidence for a binary-phase dependence of the X-ray emission from the pulsar is found with a deep observation. The binary-phase resolved spectral analysis reveals non-thermal X-ray emission of PSR B1957+20, confirming the results of previous studies. This suggests that the X-rays are mostly due to intra-binary shock emission which is strongest when the pulsar wind interacts with the ablated material from the companion star. The geometry of the peak emission is determined in our study. The marginal softening of the spectrum of the non-thermal X-ray tail may indicate that particles injected at the termination shock is dominated by synchrotron cooling.
We present a short Chandra observation that confirms a previous unidentified extended X-ray source, G308.3-1.4, as a new supernova remnant (SNR) in the Milky Way. Apart from identifying its SNR nature, a bright X-ray point source has also been discovered at the geometrical center. Its X-ray spectral properties are similar to those of a particular class of neutron star known as central compact objects (CCOs). On the other hand, the optical properties of this counterpart suggests it to be a late-type star. Together with the interesting ~ 1.4 hours X-ray periodicity found by Chandra, this system can possibly provide the first direct evidence of a compact binary survived in a supernova explosion.
We report on XMM-Newton observations of the Galactic supernova remnant G296.7–0.9. A detailed spectro-imaging X-ray study of G296.7–0.9 was performed. We detected an incomplete shell-like X-ray structure which is located near the boundary of the radio emission at a frequency of 843 MHz. The X-ray spectrum can be best described by an absorbed ionization plasma model accompanied with metallic emission lines, which suggests the plasma is shock heated. No promising compact stellar remnant associated with G296.7–0.9 was found. No Gamma-ray emission of G296.7–0.9 from Fermi-LAT telescope was detected in our study.
To describe three rare cases of nasolacrimal relapse of nasopharyngeal carcinoma, and to discuss the route of tumour spread from nasopharynx to lacrimal system as well as the relevant computed tomography findings.
We report three cases of nasolacrimal relapse in patients with previously treated nasopharyngeal carcinoma. The common initial presentations in these cases were epiphora and medial canthal swelling. The tumour spread from the nasopharynx to the lacrimal sac along the lateral nasal wall and nasolacrimal canal. Computed tomography demonstrated nasolacrimal canal invasion and osteomeatal complex obliteration by the tumour. Distant metastasis was detected in two cases.
More targeted radiotherapy should be delivered to prevent under-treatment of nasopharyngeal carcinoma. Nasolacrimal relapse of nasopharyngeal carcinoma is an advanced disease with a poor prognosis.
M. Laroussi, Old Dominion University, Virginia,M. G. Kong, Loughborough University,G. Morfill, Max-Planck-Institut für Plasmaphysik, Garching, Germany,W. Stolz, Ludwig-Maximilians-Universität Munchen
To discuss the pathophysiology of atlanto-axial subluxation as a rare complication of tonsillectomy, and to discuss the important radiological findings for diagnosis and treatment planning.
We report a case of post-tonsillectomy atlanto-axial subluxation, also known as Grisel's syndrome, in a child. On the third day after surgery, the boy presented with torticollis with no neurological deficit. Rotatory atlanto-axial subluxation was clearly shown in computed tomography scans of the neck. Cervical traction for one week successfully reduced the subluxation, with no long-term sequelae.
Pre-existing cervical ligamentous laxity and post-operative infection are believed to be the main causes of Grisel's syndrome. Although it is rare, patients are advised to seek treatment early if any neck pain or fever persists. Early diagnosis is important for better treatment outcome. Initial conservative measures are advised before more invasive cervical traction is adopted.
To review our experience of cochlear implant failure and subsequent revision surgery, and to illustrate the experience we have gained by presenting a series of lessons learned.
A combined retrospective and prospective study of revision surgery in a UK regional cochlear implant centre.
Of the 746 cochlear implantations undertaken, 33 (4.7 per cent of adults and 4.1 per cent of children) had a registered failure requiring re-implantation. The mean time to device failure was 60 months in adults and 35 months in children. Causes of cochlear implant failure were medical (n = 11), electrode displacement (n = 2), ‘hard device failure’ (n = 15) and ‘soft device failure’ (n = 5). Chronic suppurative otitis media and post-auricular mastoid abscess were the commonest causes of medical failure. There was one case of electrode array displacement as a direct result of skin flap revision surgery. In 80 per cent of cases, audiological performances were stable or improved following re-implantation.
As the number of cochlear implants increase and patients outlive the lifespan of their devices, we will face a growing number of revision procedures. Audiologists and otologists should be competent in diagnosing and managing device failure and medical complications requiring cochlear re-implantation.
High c-axis oriented CoCr-based thin films are expected for ultra-high density recording media in perpendicular magnetic recording system. In order to improve dispersion angle of c-axis of CoCr-based for perpendicular magnetic recording media, we prepared trilayered film with double underlayer using New Facing Targets Sputtering apparatus. The thickness of magnetic layer CoCrTa and double underlayer, such as interlayer Pt, paramagnetic CoCr, underlayer Ti was fixed 50nm and 20nm respectively. In order to prepare the thin film, we fixed argon gas pressure 1mTorr, substrate temperature 250°C and input current 0.5A. The crystallographic characteristics of CoCrTa layer with varying interlayer thickness (0- 20nm) have been investigated. By the result, the CoCrTa trilayered thin film with interlayer Pt showed good c-axis orientation 3.45° and 3.62° at thickness 5nm and 10nm respectively. However, CoCrTa thin film using interlayer paramagnetic CoCr showed 8.28° and 8.62° at thickness 5nm and 10nm respectively.
Current-voltage characteristics of Au contacts formed on β-SiC films grown heteroepitaxially on both nominally (100) oriented and off-axis (100) silicon substrates have been investigated. Logarithmic plots of the I-V characteristics in the forward direction indicate space charge limited current conduction through the active volume of the diodes. The β-SiC films grown on nominally (100) oriented substrates show the presence of two deep levels located approximately between 0.26 eV and 0.38 eV below the conduction band edge. In some films on nominal (100) substrates, the I-V characteristics are also influenced by additional traps which are exponentially distributed in energy with a maximum occurring at the conduction band edge. In contrast, the films deposited on off-axis substrates have only one deep level located at approximately 0.49 eV for the 2° off (100) substrates and 0.57 eV for the 4° off (100) substrates. Previous microstructural analysis revealed that the nature and density of defects in the β-SiC heteroepitaxial films on both nominal and off-axis (100) silicon are similar except that the films on nominal (100) substrates have a high density of antiphase domain boundaries. Therefore, the presence of the shallower deep-level states observed in the β-SiC films grown on nominal (100) substrates is speculated to be due to the electrical activity of antiphase domain boundaries.
In this paper, we report a multi-step rapid thermal annealing process for microwave discrete devices and monolithic integrated circuits fabrication. 2” diameter undoped liquid encapsulated Czochralski GaAs wafers were implanted with 29 Si+ and annealed without capping using incoherent light from high intensity halogen lamps. The annealing was carried out in multiple temperature steps to achieve optimum damage removal and dopant activation. As a result, wafers implanted with mid 1012 cm−2 dose exhibited 85–90% activation efficiency for 100kV implant and nearly 100% activation for 300 kV implant. In comparison with single-stepannealed wafers, multi-step-annealed wafers showed not only higher activation efficiency, but also more uniform activation, higher electron mobility and better device performance.
This paper reports the events at NCSU leading up to and including those of June 5, 1997 which produced the first demonstration of a nitride laser diode on silicon carbide – and the very first nitride laser demonstration outside of Japan. All of the laser diode samples tested at NCSU were designed, grown, and fabricated into cleaved cavity test structures at Cree Research. Laser testing at NCSU consisted of spectral emission versus current measurements, light output power versus current (L-I) measurement, and light output polarization measurements versus current. The first successful laser on silicon carbide emitted at 402.6 nm. Subsequently, lasers displaying outputs ranging from 402.6 to 430.2 have been successfully tested at NCSU.
Plasma doping (PLAD) process utilizing PH3 plasma to fabricate n-type junction with supplied bias of −1 kV and doping time of 60 sec under the room temperature is presented. The RTA process is performed at 900 °C for 10 sec. A defect-free surface is corroborated by TEM and DXRD analyses, and examined SIMS profiles reveal that shallow n+ junctions are formed with surface doping concentration of 1021atoms/cm3. The junction depth increases in proportion to the O2 gas flow when the N2 flow is fixed during the RTA process, resulting in a decreased sheet resistance. Measured doping profiles and the sheet resistance confirm that the n+ junction depth less than 52 nm and minimum sheet resistance of 313 Ω/□ are feasible.
The present study was conducted to determine the effects of a polysaccharide of Atractylodes macrophala Koidz (PAM) as a dietary additive on growth performance, immunoglobulin concentration and IL-1β expression in weaned piglets. One hundred and twenty Landrace×Yorkshire piglets weaned at 28 days old (body weight 7·5±0·07 kg) were assigned to five treatment groups (three pens/group, eight piglets/pen) fed maize/soybean-based diets supplemented with 0, 3, 6 or 9 g of PAM/kg diet or antibiotics (0·4 g flavomycin/kg+0·13 g olaquindox/kg). The experimental period was 28 days. With increasing PAM supplementation levels, average daily gain was greater (quadratic, P<0·05) and the ratio of amount fed to live weight (LW) gain (feed/gain) improved (quadratic, P<0·05) during days 14–28 and overall, and diarrhoea incidence decreased (linear, P<0·05) during days 14–28. Supplementation of PAM also increased (quadratic, P<0·05) serum concentrations of interleukin (IL)-2 and IL-6 on day 14, and increased (quadratic, P<0·05) IL-1β expression in jejunal mucosa and lymph nodes. Concentrations of PAM between 6 and 9 g/kg presented the strongest bioactivity compared to the control group or antibiotic-fed group. These findings indicate that PAM is effective in improving growth performance and cytokine response, which suggests that PAM can be used as a diet additive for weanling piglets.
In this paper, we consider a linear program with only equality constraints but containing interval and random coefficients. We first address the linear program with interval coefficients, and establish some structural properties of this linear program. On this basis, a solution method is proposed. We then move on to consider the linear program with random coefficients. Using the chance constraint approach and a new approach, the satisfaction degree approach, we obtain the two respective deterministic equivalent formulations. Then the results and the numerical solution methods obtained for these two linear models are applied to the original linear problem which contains both interval and random coefficients. By way of illustration, we consider a practical problem, where the optimal mixing proportions need to be determined for the mix slurry in the production process of aluminium with sintering. This gives rise to a linear program with interval and random coefficients. Its deterministic equivalent formulations are presented. Preliminary numerical examples show that the proposed models and the solution methods are promising.
The objectives of this study were to determine true phosphorus (P) digestibility, degradability of phytate-P complex and the endogenous P outputs associated with brown rice feeding in weanling pigs by using the simple linear regression analysis technique. Six barrows with an average initial body weight of 12.5 kg were fitted with a T-cannula and fed six diets according to a 6 × 6 Latin-square design. Six maize starch-based diets, containing six levels of P at 0.80, 1.36, 1.93, 2.49, 3.04, and 3.61 g/kg per kg dry-matter (DM) intake (DMI), were formulated with brown rice. Each experimental period lasted 10 days. After a 7-day adaptation, all faecal samples were collected on days 8 and 9. Ileal digesta samples were collected for a total of 24 h on day 10. The apparent ileal and faecal P digestibility values of brown rice were affected ( P < 0.01) by the P contents in the assay diets. The apparent ileal and faecal P digestibility values increased from − 48.0 to 36.7% and from − 35.6 to 40.0%, respectively, as P content increased from 0.80 to 3.61 g/kg DMI. Linear relationships ( P < 0.05), expressed as g/kg DMI, between the apparent ileal and faecal digestible P and dietary levels of P, suggested that true P digestibility and the endogenous P outputs associated with brown rice feeding could be determined by using the simple regression analysis technique. There were no differences ( P>0.05) in true P digestibility values (57.7 ± 5.4 v. 58.2 ± 5.9%), phytate P degradability (76.4 ± 6.7 v. 79.0 ± 4.4%) and the endogenous P outputs (0.812 ± 0..096 v. 0.725 ± 0.083 g/kg DMI) between the ileal and the faecal levels. The endogenous faecal P output represented 14 and 25% of the National Research Council (1998) recommended daily total and available P requirements in the weanling pig, respectively. About 58% of the total P in brown rice could be digested and absorbed by the weanling pig. Our results suggest that the large intestine of the weanling pigs does not play a significant role in the digestion of P in brown rice. Diet formulation on the basis of total or apparent P digestibility with brown rice may lead to P overfeeding and excessive P excretion in pigs.
Cyst fluid (CF) of Taenia solium metacestode (TsM) is an important source of serodiagnostic antigens. We have investigated the molecular characteristics of the 120 kDa protein complex in TsM CF purified by fast performance liquid chromatography. The structure of the purified protein was characterized by a variety of proteomic analyses. The protein was found to consist of 2 major components of 42–46 and 22–28 kDa, and shared 3 subunits of 14, 16 and 18 kDa. The 42–46 kDa component was determined to contain 3 additional subunits of 22, 28 and 38 kDa. These 6 subunits were shown to originate from either the 14 or 18 kDa precursor. We assessed the antibody reactivity of the native protein, its individual subunits and the recombinant 14 and 18 kDa proteins, and found that the 120 kDa protein, particularly 14 and 18 kDa subunits revealed high reliability for differentiation of active and mixed stage NC from chronic NC. The subunits of the 120 kDa protein complex identified herein represent some of the low-molecular weight glycoproteins which have been described in several previous studies. Recognizing and understanding the structural and immunological relationship of these proteins will facilitate the development of new serodiagnostic assays.