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PurposeTo compare the performance of unbiased high-throughput sequencing with pathogen directed PCR using DNA isolated from archived ocular fluid, approaches that are compatible with the current sample handling practice of ophthalmologists.DesignRetrospective molecular study of banked vitreous samples.MethodsWe evaluated a metagenomic DNA sequencing-based approach (DNA-seq) using archived positive (n= 31) and negative (n=36) vitreous specimens as determined by reference pathogen-specific PCR assays (herpes simplex virus 1 and 2, cytomegalovirus, varicella-zoster virus, andToxoplasma gondii). Pathogens were identified using a rapid computational pipeline to analyze the non-host sequences obtained from DNA-seq. Clinical samples were de-identified and laboratory personnel handling the samples and interpreting the data were masked.ResultsMetagenomic DNA sequencing detected 87% of positive reference samples. In the presumed negative reference samples, DNA-seq detected an additional 6 different pathogens in 8 samples (22% of negative samples) that were either not detected or not targeted with pathogen-specific PCR assays. Infectious agents identified only with DNA-seq wereCandida dubliniensis,Klebsiella pneumoniae, human herpesvirus 6 (HHV-6), and human T-cell leukemia virus type 1 (HTLV-1). Discordant samples were independently verified in CLIA-certified laboratories. CMV sequences were compared against the antiviral mutation database and 3 of the samples were found to have mutations conferring ganciclovir resistance.ConclusionsMetagenomic DNA sequencing was highly concordant with pathogen-directed PCRs. The unbiased nature of metagenomics DNA sequencing allowed an expanded scope of pathogen detection, including bacteria, fungal species, and viruses, resolving 22% of cases that had previously escaped detection by routine pathogen-specific PCRs. The detection of drug resistance mutations highlights the potential for unbiased sequencing to provide clinically actionable information beyond pathogen species detection.

Trachoma control strategies, including latrine construction and antibiotic distribution, are directed at reducing ocular chlamydia, but may have additional benefits. In a cluster-randomized clinical trial, 24 subkebeles (administrative geographic units) in Ethiopia were offered a single mass azithromycin treatment, and half were randomized to receive an intensive latrine promotion. At a follow-up census 26 months after the baseline treatment, 320 persons had died. The mortality rate of children 1–5 years of age was 3.87 (95% confidence interval [CI] = 2.19–6.82) per 1,000 person-years in the latrine promotion arm, and 2.72 (95% CI = 1.37–5.42) per 1,000 person-years in the control arm. In a multi-level mixed effects logistic regression model controlling for age, there was no difference in mortality in persons randomized into the latrine or control arms (odds ratio = 1.18, 95% CI = 0.89–1.58). Latrine promotion provided no additional effect on mortality in the context of an azithromycin distribution program (clinicaltrials.gov, #NCT00322972).

Nanoscale H-free C/Cr coatings have been produced by unbalanced magnetron (UBM) sputtering with high ion-irradiation. The coating was a nanocomposite composed of nanoscale C clusters in a chromium carbide crystalline matrix. Reciprocating wear testing of the coating on stainless steel substrates was undertaken against an Al 2 O 3 ball counterface (4 mm) at 5 Hz and 1 N load. The friction coefficient went through three stages from a low friction of 0.10 to a relatively high friction of 0.24. Plan-view worn surfaces were investigated using Raman spectroscopy and scanning electron microscopy. Roll-shaped wear debris were present perpendicular to the sliding direction. The rolls contained graphitic carbon and Cr 2 O 3 . Cross-sections of the worn surfaces were examined using transmission electron microscopy (TEM) of focused ion beam derived specimens, which showed that oxidational wear was important. The composition of the rolls and tribofilm is correlated with the Raman spectroscopy and SEM investigations. A tentative mechanism of the origin and evolution of the wear debris is proposed.

Summary The World Health Organization (WHO) recommends environmental improvements such as latrine construction in the integrated trachoma control strategy, SAFE. We report a cluster-randomized trial assessing the effect of intensive latrine promotion on emergence of infection with ocular Chlamydia trachomatis after mass treatment with antibiotics. Twenty-four communities in Goncha Seso Enesie woreda, Amhara Regional State, Ethiopia, were enumerated, and a random selection of 60 children aged 0–9 years in each was monitored for clinical signs of trachoma and ocular chlamydial infection at baseline, 12 and 24 months. All community members were offered treatment with a single dose of oral azithromycin or topical tetracycline. After treatment, 12 subkebeles were randomized to receive intensive latrine promotion. Mean cluster ocular infection in the latrine and the non-latrine arms were reduced from 45.5% (95% CI 34.1–56.8%) and 43.0% (95% CI 31.1–54.8%), respectively, at baseline to 14.6% (95% CI 7.4–21.8%) and 14.8% (95% CI 8.9–20.8%), respectively, at 24 months (P = 0.93). Clinical signs fell from 72.0% (95% CI 58.2–85.5%) and 61.3% (95% CI 44.0–78.5%) at baseline to 45.8% (36.0–55.6%) and 48.5% (34.0–62.9%), respectively, at 24 months (P = 0.69). At 24 months, estimated household latrine coverage and use were 80.8% and 61.7%, respectively, where there had been intensive latrine promotion and 30.0% and 25.0% respectively in the single treatment only arm. We were unable to detect a difference in the prevalence of ocular chlamydial infection in children due to latrine construction.

Background. Mass azithromycin distributions are used to clear ocular strains of chlamydia that cause trachoma, but treatments may also affect respiratory infections, diarrhea, and malaria. Here, we monitor a large cohort in which almost 90% of individuals received azithromycin. We assess whether receiving treatment is associated with reduced all-cause and infectious childhood mortality. Methods. As part of a clinical trial for trachoma, a census was conducted in 24 communities in rural Ethiopia. All individuals >1 year of age were eligible for single-dose oral azithromycin, although antibiotic coverage was not universal. A follow-up census was performed 26 months after treatment to estimate all-cause mortality among children 1–5 years of age, and verbal autopsies were performed to identify infectious mortality. Results. The cohort included 35,052 individuals >1 year of age and 5507 children 1–5 years of age, of whom 4914 received a dose of azithromycin. All-cause mortality was significantly lower among those 1–5-year-old children who received azithromycin (odds ratio [OR] 5 0.35 [95% confidence interval {CI}, 0.17–0.74]), as was infectious mortality (OR 5 0.20 [95% CI, 0.07–0.58]). When individuals were compared only with members of the same household, azithromycin treatment was still associated with reduced all-cause mortality in children 1–5 years of age (OR 5 0.40 [95% CI, 0.16–0.96]), although this relationship was not statistically significant for infectious mortality (OR 5 0.35 [95% CI, 0.10–1.28]). Conclusions. This study demonstrated an association between mass oral azithromycin treatment and reduced all-cause and infectious childhood mortality. This relationship could not be attributed to bias at the level of the household. Mass azithromycin distributions may have benefits unrelated to trachoma.

In 1996, it was found that the Beilby layer on rolled aluminium sheet could be imaged in the transmission electron microscope (TEM) on ultramicrotomed cross sections of the sheet surface. Following from this observation, we have examined Beilby layers on all types of aluminium surfaces that have been subject to high shear processing treatments such as rolling, grinding or machining. The layers are microcrystalline rather than amorphous, and they strongly influence properties like corrosion resistance and reflectance. Preferential precipitation in these deformed surface layers results in their electrochemical activation and it is responsible for the development of underfilm corrosion in most architectural and automotive alloys. More recently, it has been possible to directly image Beilby layers on ultramicrotomed stubs using the new generation of low kilovoltage high-resolution scanning electron microscopes and to carry out high-resolution TEM of sections cut from precisely located surface features. The paper presents an overview of all the recent investigations of high shear induced Beilby layers on aluminium alloys and discusses their control of surface properties.

The thermal stability of a hydrogen free C/CrC coating was the focus of this study. The coating was deposited by unbalanced magnetron sputtering of graphite and Cr metal targets in a non-reactive argon atmosphere at high ion irradiation conditions. The coating possessed a nanocomposite structure with amorphous carbon embedded in a metastable NaCl (B1) structure CrC matrix. The nanometre amorphous carbon clusters formed layers within the CrC matrix, producing a self-assembled multilayer structure. In this paper, degradation of the multilayer nanocomposite structure and NaCl (B1) structure CrC phase was evaluated by annealing at 700 degrees C in Ar + 5%H-2 atmosphere for 30 minutes. Microstructures of the as-deposited and annealed coating were characterised using Raman spectroscopy and cross-sectional transmission electron microscopy (TEM) coupled with electron energy filtered mapping. Raman spectroscopy suggested the presence of graphitic carbon in the coating after annealing, together with a trace of Cr2O3 associated with coating growth defects. TEM investigation of the cross sections of annealed coating revealed regions of C enrichment at the very top (similar to 40 nm) and bottom (similar to 10 nm) of the coating, which was confirmed by Raman spectroscopy. However, the central region of the coating retained its composite C/CrC multilayer structure. Tentative mechanisms of C enrichment are proposed. The advantages and limitations of Raman spectroscopy and TEM techniques in studying C/CrC coating are also discussed.

This paper presents experimental results from an ongoing study investigating the flexural bond strength, initial shear strength and compressive strength of brickwork built using natural hydraulic lime mortars. All tests were conducted in accordance with relevant standard procedures. Flexural bond strengths, with planes of failure parallel and perpendicular to bed joints, were determined by panel (wallette) tests. Bond wrench testing of stack-bonded prisms was also conducted to investigate further the material influences on flexural strength. The main parameters studied in this investigation were mortar mix design (binder : aggregate ratio; lime grade) and brick water absorption characteristics. The flexural bond strength and initial shear strength of the brickwork in general increased with mortar strength, but flexural bond strength was significantly impaired by both low and high brick water absorption. The bond wrench test was found to be a reliable, quick and easy, alternative test procedure to determine flexural strength (with plane of failure) parallel to the bed joints.

Hard wear-resistant coatings require excellent oxidation resistance for high-speed machining operations. Moreover, the oxide formed is integral to the frictional behavior and therefore the success of the coating. The oxidation behavior of TiAlN/VN nanoscale multilayer coatings was investigated using high-resolution techniques and was compared with TiN and TiAlN coatings. Static oxidation of TiAlN/VN films was studied in the range 550 °C to 700 °C, and characterized by high-temperature in-situ X-ray diffraction (XRD) and scanning transmission electron microscopy/energy-dispersive X-ray/electron energy loss spectroscopy (STEM/EDX/EELS) of selected surface cross sections. The oxidation resistance of TiAlN/VN was found to be controlled by the VN layers, and consequently, oxidation was initiated at a lower temperature than TiN and TiAlN coatings. The onset of oxidation of the TiAlN/VN coating was found to be ≥550 °C with the VN being the first component to oxidize. At temperatures >600 °C, a duplex oxide structure was formed; the inner layer comprised a porous region of Ti-rich and V-rich nanocrystallites, while several phases were observed in the outer region, including V2O5, TiO2, and AlVO4. V2O5 was the dominant oxide at the outer layer at ≥638 °C. The outward diffusion of V depended on the species present; in the inner layer, V was present as V3+, V4+, whereas a significant V5+ was dominant in the outer layer of oxide at ≥638 °C. An Au marker study suggested roughly equal diffusivity of cations outward, and oxygen inward diffusion occurred during oxidation.

Female patients, 50 years old, have a recurrent unilateral aggravating headache for 5 years. Without runny nose, sneezing, nasal hemorrhage, smell or vision loss. Prefessional examination: there is a visible hoar neoplasm in the right middle nasal meatus With smooth surface and rich in vascular. The nasopharyngeal MRI shows that there is a occupancy lesion in the right nasal cavity and sinuses, well-demarcated, about 21. 5 mm x 25.5 mm x 37.0 mm. Angiofibroma is the most likely diagnosis. Postoperative pathological section shows that tumor are hypercellular, which contains big nucleus. Cells are spindle or short fusiform shape, there are stripes and nuclear division in some cells. There are vortex structures in partial region. Immunohistochemical examination shows: CD34(++), Ki-67 (5%), CD68(-), Des (-), NSE(+), S-100(++), SMA(-), EMA (+). Histopathologic diagnosis: atypical meningioma, some were differentiated to rhabdoid meningioma. The final diagnosis is malignant meningioma in nasal cavity and paranasal sinuses.

PurposeTrachoma surveillance is most commonly performed by direct observation, usually by non-ophthalmologists using the World Health Organization (WHO) simplified grading system. However, conjunctival photographs may offer several benefits over direct clinical observation, including the potential for greater inter-rater agreement. This study assesses whether inter-rater agreement of trachoma grading differs when trained graders review conjunctival photographs compared to when they perform conjunctival examinations in the field.MethodsThree trained trachoma graders each performed an independent examination of the everted right tarsal conjunctiva of 269 children aged 0-9 years, and then reviewed photographs of these same conjunctivae in a random order. For each eye, the grader documented the presence or absence of follicular trachoma (TF) and intense trachomatous inflammation (TI) according to the WHO simplified grading system.ResultsInter-rater agreement for the grade of TF was significantly higher in the field (kappa coefficient, κ, 0.73, 95% confidence interval, CI 0.67-0.80) than by photographic review (κ = 0.55, 95% CI 0.49-0.63; difference in κ between field grading and photo grading 0.18, 95% CI 0.09-0.26). When field and photographic grades were each assessed as the consensus grade from the three graders, agreement between in-field and photographic graders was high for TF (κ = 0.75, 95% CI 0.68-0.84).ConclusionsIn an area with hyperendemic trachoma, inter-rater agreement was lower for photographic assessment of trachoma than for in-field assessment. However, the trachoma grade reached by a consensus of photographic graders agreed well with the grade given by a consensus of in-field graders.

Thin-film structures consisting of alternating nanoscale multilayers show substantial hardness increases compared with monolithic coatings of the constituent materials. Coatings, such as TiAlN/VN are deposited using PVD with individual coating bi-layer thickness of ~3nm. Since TiAlN and VN are isostructural and mutually soluble, mixing of the two layers during deposition is expected, which will inevitably affect properties. Energy filtered TEM using a field emission gun source allowed important information on layer structure, but failed to reveal details 600°C, a duplex oxide structure was formed, with several phases observed, including V2O5, TiO2 and AlVO4, with V2O5 being the dominant oxide at the outer layer at 638°C. These coatings exhibit low friction in dry sliding which is believed to arise from the inherently low friction of V2O5. Focused ion beam studies of wear tests at 630°C confirmed that the contact surface comprised small (~50nm), equiaxed and largely agglomerated V2O5 crystals, confirming the hypothesis.

Lead zirconate titanate (PZT) thin films were prepared on platinized silicon substrates by dip-coating using a modified diol-based sol-gel route without and with up to 5 mol% PZT nanometric seeds dispersed in the precursor sol. A metastable intermetallic Pt x Pb phase formed at the early stages of heat treatment. XRD, TEM, and RBS revealed that the thickness and stoichiometry of the Pt x Pb layer varied with the concentration of seeds and heat treatment of the films. The relation of the Pt x Pb layer to the final crystalline texture of the PZT thin films is reported and discussed.

Chemical distribution of individual layers within a TiAlN/VN multilayer structure was characterised using a field emission gun transmission electron microscope, coupled with energy-filtered elemental mapping and high-angle annular dark field imaging. Bright field TEM micrographs using zero-loss electrons indicated the presence of alternating TiAlN and VN layers with a periodicity of similar to 3 nm. Electron spectroscopic images (ESI) using the Ti-L-2.3 and V-L-2.3 edges were used to determine the Ti and V composition profiles of layers and confirmed the complementary distribution of Ti and V. ESI demonstrated an additional modulation super-imposed on the basic period of the coatings, which was confirmed by Z-contrast imaging using scanning transmission electron microscopy. The additional modulation was related to the threefold rotational geometry used in the deposition process. Film growth and elemental distributions were therefore theoretically predicted in association with substrate rotation. The experimental compositional profiles and the prediction showed good agreement. The implications of the compositional modulation on key process parameters are discussed. (C) 2003 Elsevier B.V. All rights reserved.

Integrated lead zirconate titanate thin films deposited on Pt/Ti/SiO2/Si substrates using a novel triol-based route were characterized using X-ray diffraction and transmission electron microscopy. Crack-free single-layer PZT films of up to 200 nm thick were prepared by triol-based sol–gel processing onto Pt/Ti/SiO2/Si substrates. Films ∼75 nm thick exhibited a microstructure free of pores and second phase. As film thickness increased, film texture changed from {100} to {111} perovskite. Essentially, single-phase multilayer films could be prepared by the deposition and pyrolysis of several 75 nm layers, followed by a single crystallization step. The influence of heat-treatment schedule on the microstructure and orientation of the multilayer films is discussed. Comparison has been made between multilayer films prepared using the triol-based sol and an inverted mixing order/acetic acid-based sol.

Nanoscale multilayer TiAlN/VN coatings were grown using combined cathodic arc/unbalanced magnetron deposition (arc bond sputtering, ABS) in an industrial-sized physical vapour deposition machine. The thermal behaviour of TiAlN/VN coatings in air was studied using thermo-gravimetric analysis, X-ray diffraction (XRD), scanning electron microscopy and transmission electron microscopy (TEM). Coatings were heat treated in air for 30 min at 550, 600, 638 and 672 degreesC. Surface oxidation occurred at greater than or equal to 550 degreesC at the coating surface. V2O5 was found to form at > 600 degreesC by XRD. V2O5, TiO2, AlVO4, were identified at 600 degreesC, with possible Al2TiO5, and VO2 phases. TEM revealed a non-uniform oxide/coating interface, with preferential oxidation along columnar grain boundaries, presumably because these provide a fast track for diffusion. At 672 degreesC, the entire coating volume was oxidised, and the coating spalled. (C) 2003 Elsevier B.V. All rights reserved.

Nano-scaled multilayered TiAlN/VN coatings have been grown on stainless steel and M2 high speed steel substrates at U-B = - 85 V in an industrial, four target, Hauzer HTC 1000 coater using combined cathodic steered arc etching/unbalanced magnetron sputtering. X-ray diffraction (XRD) has been used to investigate the effects of process parameters (Target Power) on texture evolution (using texture parameter T*), development of residual stress (sin(2) psi method) and nano-scale multilayer period. The composition of the coating was determined using energy dispersive X-ray analysis. The thermal behaviour of the coatings in air was studied using thermo-gravimetric analysis, XRD and scanning electron microscopy. The bi-layer period varied between 2.8 and 3.1 nm and in all cases a {1 1 0} texture developed with a maximum value T* = 4.9. The residual stress varied between -5.2 and -7.4 GPa. The onset of rapid oxidation occurred between 628 and 645 degreesC depending on the (Ti+Al):V ratio. After oxidation in air at 550 degreesC AlVO4, TiO2 and V2O5 Phases were identified by XRD with the AlVO4, TiO2 being the major phases. The formation of AlVO4 appears to disrupt the formation of Al2O3 which imparts oxidation resistance to TiAlN based coatings. Increasing the temperature to 600 and 640 degreesC led to a dramatic increase in the formation of V2O5 which was highly oriented (0 0 1) with a plate-like morphology. At 640 degreesC there was no evidence of the coating on XRD. Increasing the temperature to 670 degreesC led to further formation of AlVO4 and a dramatic reduction in V2O5. (C) 2003 Elsevier B.V. All rights reserved.

Advanced analytical transmission electron microscopy has been used to investigate microstructural evolution during pyrolysis in triol-based sol-gel thin films. At pyrolysis temperatures up to 300 °C, the films remained amorphous; however, nanometer-sized precipitates were observed in films heat-treated up to 400 °C for 10 min. Analytical transmission electron microscopy indicated that the precipitates were Pb-rich, as well as deficient in O, Ti, and Zr. Films pyrolyzed up to 500 °C for 10 min were composed of a nanocrystalline pyrochlore phase; however, pores could be observed, situated in the same position as the nanometer-sized precipitates at 400 °C. Face-centered cubic Pb-rich crystallites were also present on the surface of pyrolyzed films but absent in the fully crystallized films annealed at 650 °C. A tentative mechanism is proposed to explain these observations.

Pb(Zr 53 Ti 47 )O 3 thin films on Pt/Ti/SiO 2 /Si substrates were processed by a triol (1,1,1-tris(hydroxymethyl)ethane) based sol-gel route. Film microstructures were characterised using transmission electron microscope (TEM) equipped with electron energy loss spectroscopy and nano-probe energy dispersive X-ray analysis with the intention of revealing the crystallisation mechanism. Porosity developed in films >75nm, whereas films h 75nm thick were single phase and pore free. An investigation of low temperature heat treatment schedule on phase evolution was carried out to elucidate the origin of the porosity in films >75nm. TEM results indicated that porosity was associated with the formation of Pb-rich precipitates during low temperature pyrolysis (∼400°C). Inhomogeneity of the pyrolysed microstructure is responsible for inhomogeneity in the crystallised film >75nm.

The Young's modulus of 6H single crystal silicon carbide (SiC) was tested with micro cantilevers that had a range of cross-sectional dimensions with surfaces cleaned under different accelerating voltages of Ga+ beam. A clear size effect is seen with Young's modulus decreasing as the cross-sectional area reduces. One of the possible reasons for such size effect is the Ga+ induced damage on all surfaces of the cantilever. Transmission electron microscopy (TEM) was used to analyse the degree of damage, and the measurements of damage is compared to predictions by SRIM irradiation simulation.

Background Antibiotic use on animals demonstrates improved growth regardless of whether or not there is clinical evidence of infectious disease. Antibiotics used for trachoma control may play an unintended benefit of improving child growth. Methodology In this sub-study of a larger randomized controlled trial, we assess anthropometry of pre-school children in a community-randomized trial of mass oral azithromycin distributions for trachoma in Niger. We measured height, weight, and mid-upper arm circumference (MUAC) in 12 communities randomized to receive annual mass azithromycin treatment of everyone versus 12 communities randomized to receive biannual mass azithromycin treatments for children, 3 years after the initial mass treatment. We collected measurements in 1,034 children aged 6–60 months of age. Principal Findings We found no difference in the prevalence of wasting among children in the 12 annually treated communities that received three mass azithromycin distributions compared to the 12 biannually treated communities that received six mass azithromycin distributions (odds ratio = 0.88, 95% confidence interval = 0.53 to 1.49). Conclusions/Significance We were unable to demonstrate a statistically significant difference in stunting, underweight, and low MUAC of pre-school children in communities randomized to annual mass azithromycin treatment or biannual mass azithromycin treatment. The role of antibiotics on child growth and nutrition remains unclear, but larger studies and longitudinal trials may help determine any association., Author Summary Recent studies suggest that antibiotic use could have an effect on growth in humans. Azithromycin is an antibiotic used for trachoma control, and hence, may have an unintended benefit of improving child growth. Niger is a trachoma-endemic country where mass antibiotic distributions for trachoma take place and where malnutrition is widespread among children. In addition, azithromycin may have an effect on common childhood diseases associated with malnutrition, such as diarrhea, pneumonia, and malaria. In a community-randomized trachoma trial in Matameye, Niger, we assessed child growth by measuring height, weight, and mid-upper arm circumference of pre-school children who have received 3 years of annual or biannual mass azithromycin treatment. While these measures were better in the biannually treated communities, the difference was not statistically significant. Thus, further research will help determine the impact of antibiotics on child growth and nutrition.

Background: The World Health Organization recommends annual treatment of entire trachoma-endemic communities, although children typically have a higher load, longer duration, and greater likelihood of infection. Methods: Forty-eight communities in Matameye, Niger, were randomized to annual oral azithromycin treatment of the entire community or biannual treatment of children aged 0-12 years only. Both children and adults were monitored for ocular chlamydial infection by polymerase chain reaction. Results: The prevalence of childhood infection was reduced in the annually treated arm from 21.2% (95% confidence interval [CI], 15.2%-28.0%) at baseline to 5.8% (95% CI, 3.2%-9.0%) at 36 months (P < .001) and in the biannual arm from 20.2% (95% CI, 15.5%-25.3%) to 3.8% (95% CI, 2.2%-6.0%; P < .001). Adult infection in the annual arm was reduced from 1.7% (95% CI, .9%-2.7%) to 0.3% (95% CI, .0%-.7%) and in the biannual arm from 1.2% (95% CI, .5%-2.2%) to 0.0% (95% CI, .0%-.7%; P = .005). The effect of biannual treatment of children compared with annual treatment of the entire community in both children (95% CI, -.04% to .02%) and adults (95% CI, .9%-2.7%) excluded the prespecified noninferiority threshold of 6% (P = .003 and P < .001, respectively). Conclusions: Periodic distribution of antibiotics to children in trachoma-endemic communities reduces chlamydial infection in both children and untreated adults, suggesting a form of herd protection. Biannual treatment of children was comparable to (specifically, noninferior to) annual treatment of the entire community, and may offer lower antibiotic use and other logistical advantages. Clinical Trials Registration: NCT00792922.

High-resolution electron microscopy was employed to characterize the interface structure of a cast Al-Mg-Si-Bi-Pb aluminium(6262)-based composite reinforced by cr alumina particles with a trace of beta alumina in order to investigate the behaviour of alloying elements in cast composites, Except for a few primary Mg2Si particles, few reaction products were detected at the interface of Al/alpha -Al2O3 due to the unfavourable reaction kinetics during the squeeze-casting process. The Mg2Si particle has an orientation relationship with alpha -Al2O3 of [011](Mg2Si)//[1 (2) over bar 10](alpha -Al2O3) (1 (1) over bar1)(Mg2Si)//(0006)(alpha -Al2O3). A significant amount of MgAl2O4 was found on the surface of the beta -Al2O3 particles, which is in contrast to the small degree of reaction found on alpha -Al2O3 particles, MgAl2O4 and beta -Al2O3 particles have the following orientation relationship: [011](MgA12O4)//[1 (2) over bar 10](beta -Al2O3) (1 (1) over bar1) (MgAl2O4)//(0006)(beta -Al2O3). The similar crystal structure of beta -Al2O3 to MgAl2O4 favours MgAl2O4 nucleation and growth on the surface of beta -Al2O3. Interfacial energy minimization dominates the atomic structure of the interface with the result that close packed planes and directions in the Al2O3 reinforcement and reaction products are parallel to the interfaces. Bi and Pb were found in the form of metallic nanometre particles between Al2O3 particles, or between the MgAl2O4 and Al2O3 particles, or in the open channels of beta -Al2O3 filled by the Al matrix.

Segregation of yttrium induces the formation of Y0.25Zr0.75O2-x and Y0.5Zr0.5O2-y microdomains, with L1(2)- and L1(0)-like ordered structures, in ZrO2-6mol%Y2O3 ceramics in both the sintered and annealed states. The compositions of precipitates such as (chi L), (chi S), (chi SS), and small precipitates formed inside XL, in Cu-11.88Al-5.06Ni-1.63Mn-0.96Ti (wt.%) shape memory alloys have been determined. Under electron beam irradiation, four types of dynamic behavior of the G.P. zones were observed in the Al-6.58Zn-2.33Mg-2.40Cu (wt.%) alloy. The G.P. zone and "G.P. zone-like" defect structures were also distinguished. Lattice distortion profile in the GaAs/InxGa1-xAs superlattice and two-dimensional lattice distortion around a 60 degrees dislocation core in the InAs(x)P(1-)x/InP superlattice were determined. (C) Elsevier Science Inc., 2000. All rights reserved.

The World Health Organization has distributed millions of doses of azithromycin to control the ocular chlamydial infection that causes trachoma. Theoretically, a loftier goal of elimination is feasible. Here, we demonstrate that, although local elimination of infection in the most severely affected communities is difficult, it is possible with biannual antibiotic distributions.

Background Control programs for trachoma use mass antibiotic distributions to treat ocular Chlamydia trachomatis in an effort to eliminate this disease worldwide. To determine whether children infected with ocular Chlamydia are more likely to present later for examination than those who are uninfected, we compare the order of presentation for examination of children 0–5 years, and the presence of ocular Chlamydia by PCR in 4 villages in Niger where trachoma is endemic. Methods We conducted a cluster-randomized, controlled trial where 48 randomly selected villages in Niger are divided into 4 study arms of different mass treatment strategies. In a substudy of the main trial, we randomly selected 1 village from each of the 4 study arms (4 total villages) and we evaluated the odds of ocular Chlamydia versus the rank order of presentation for examination and laboratory assessment before treatment was offered. Findings We found the odds of harboring ocular Chlamydia dropped by more than 70% from the first child examined to the last child examined (OR 0.27, 95% CI 0.13–0.59, P = 0.001) in the 4 randomly selected villages. We found the odds of active trachoma dropped by 80% from the first child examined to the last child examined (OR 0.20, 95% CI 0.10–0.4, P, Author Summary Trachoma is the most common cause of blindness from an infection in the world. The bacterium that causes trachoma is called Chlamydia trachomatis and it can be treated with the antibiotic azithromycin. Experts recommend trying to reach at least 80% of children for treatment in a community but it is unknown if this is necessary. We began a clinical trial in Niger in 48 villages in the summer of 2010 with mass drug administration (MDA) of azithromycin. We found that the odds of an eye infection were the highest in the first children to come for an examination. This means the extra time and money needed to reach all of the children in a village may provide diminishing returns because the easiest children to reach have the highest odds of infection. Perhaps it would be better to try to reach more villages for MDA instead of spending a lot of time and money trying to reach every single child in every single village.

This paper builds on previous work investigating the flexural bond strength, initial shear strength and compressive strength of fired clay brickwork built using hydraulic lime mortars. It has been shown that whilst flexural bond strength and initial shear strength of the brickwork generally increased with mortar strength, flexural bond strength was significantly impaired by both low and high brick water absorption. This paper describes a study of the pore size distribution of the surfaces of brick and mortar at the brick/mortar interface using Mercury Intrusion Porosimetry. The paper identifies critical pore sizes at the brick surface which would appear to govern resultant bond strength.

Twelve trachoma-hyperendemic communities were treatedwith 3 annual mass azithromycin distributions. Childrenaged 0–9 years were monitored 1 year following the thirdtreatment. An RNA-based test detected ocular chlamydialinfection in more children than did a DNA-based test (6.9%vs 4.2%), and in a larger number of communities (8 vs 7).Trachoma is a blinding disease caused by ocular infection withChlamydia trachomatis. The World Health Organization (WHO)has targeted trachoma for elimination as a public health concernby the year 2020. Mass antibiotic distributions are an importantcomponent of WHO’s trachoma elimination strategy. Currentguidelines recommend annual mass azithromycin treatmentsin districts with sufficient trachoma, with reassessment after 3annual treatments [1].Most studies that have monitored for trachoma after 3 massazithromycin distributions have reported only the clinical signsof trachoma. However, there is poor agreement between theclinical signs of trachoma and ocular chlamydial infection aftermass antibiotic treatments, likely because clinical signs persistfor months after ocular chlamydia has been cleared [2]. The fewstudies that have monitored ocular chlamydia after 3 repeatedmass antibiotic distributions have done so using commerciallyavailable nucleic acid amplification tests (NAATs) targetingchlamydial DNA [3, 4]. Recently, studies in both the trachomaand sexually transmitted disease literature have demonstratedthat RNA-based NAATs are more sensitive than these DNA-based tests for detecting chlamydia in an individual [5–7]. RNA-based tests have an additional target capture step and a moreabundant genetic target, either of which may contribute to theincreased sensitivity. It is possible that communities without anyDNA evidence of ocular chlamydia could nonetheless have in-fection detectable by an RNA-based test—although evidence forthis was not found in a previous study [8]. In this report, we useboth RNA-based and DNA-based tests to monitor 12 trachoma-hyperendemic communities that have been treated with 3 an-nual mass azithromycin distributions.METHODSDuring a cluster-randomized clinical trial conducted in Ethiopia,12 randomly selected subkebeles (subdistricts) were treated with3 annual mass azithromycin treatments (clinicaltrials.gov identi-fier NCT00322972) [12]. We performed an enumerative censusand mass azithromycin distribution in all 12 subkebeles at months0, 12, and 24 of the study. At each distribution, auxiliary healthworkers offered a single dose of directly observed azithromycin(1 gram for adults, 20 mg/kg for children) to all persons aged$1year.We performed monitoring in a randomly selected sentinelcommunityfromeachsubkebele.Ineachofthe12sentinelcommunities, 50 randomly chosen children aged 0–9 years un-derwent conjunctival examination and swabbing at baseline andmonth 36 (ie, 1 year after the third mass treatment). Separaterandom samples of children were selected at each time point,based on the most recent census. At each monitoring visit, 1 of 13trained examiners assessed the upper right tarsal conjunctiva forfollicular trachomatous inflammation (TF) and intense tracho-matous inflammation (TI) according to the WHO simplifiedgrading system [9]. The examiner then passed a Dacron swab3 times over the upper right tarsal conjunctiva. At month 36, anadditional swab for chlamydial RNA was collected in a similarfashion, using swabs and transport media from the APTIMA-CTUnisex Swab Specimen Collection Kit (Gen-Probe). RNA swabswere always collected after Dacron swabs. Examiners used the

During a cluster-randomized clinical trial for trachoma in Ethiopia, two rounds of adverse event surveillance were performed in a random sample of communities after community-wide mass azithromycin treatment. The prevalence of any reported adverse event ranged from 4.9% to 7.0% in children 1–9 years of age and from 17.0% to 18.7% in persons ≥ 10 years of age. Adverse events appeared to cluster by household and perhaps by village. Mass azithromycin distributions were well tolerated in this setting.

Jeremy Keenan and colleagues report that during a cluster-randomized clinical trial in Ethiopia, nasopharyngeal pneumococcal resistance to macrolides was significantly higher in communities randomized to receive azithromycin compared with untreated control communities., Background It is widely thought that widespread antibiotic use selects for community antibiotic resistance, though this has been difficult to prove in the setting of a community-randomized clinical trial. In this study, we used a randomized clinical trial design to assess whether macrolide resistance was higher in communities treated with mass azithromycin for trachoma, compared to untreated control communities. Methods and Findings In a cluster-randomized trial for trachoma control in Ethiopia, 12 communities were randomized to receive mass azithromycin treatment of children aged 1–10 years at months 0, 3, 6, and 9. Twelve control communities were randomized to receive no antibiotic treatments until the conclusion of the study. Nasopharyngeal swabs were collected from randomly selected children in the treated group at baseline and month 12, and in the control group at month 12. Antibiotic susceptibility testing was performed on Streptococcus pneumoniae isolated from the swabs using Etest strips. In the treated group, the mean prevalence of azithromycin resistance among all monitored children increased from 3.6% (95% confidence interval [CI] 0.8%–8.9%) at baseline, to 46.9% (37.5%–57.5%) at month 12 (p = 0.003). In control communities, azithromycin resistance was 9.2% (95% CI 6.7%–13.3%) at month 12, significantly lower than the treated group (p, Editors' Summary Background In 1928, Alexander Fleming discovered penicillin, the first antibiotic (a drug that kills bacteria). By the early 1940s, scientists were able to make large quantities of penicillin and, in the following decades, several other classes of powerful antibiotics were discovered. For example, erythromycin—the first macrolide antibiotic—was developed in the early 1950s. For a time, it looked like bacteria and the diseases that they cause had been defeated. But bacteria rapidly become resistant to antibiotics. Under the “selective pressure” of an antibiotic, bacteria that have acquired a random change in their DNA that allows them to survive in the antibiotic's presence outgrow nonresistant bacteria. What's more, bacteria can transfer antibiotic resistance genes between themselves. Nowadays, antibiotic resistance is a major public health concern. Almost every type of disease-causing bacteria has developed resistance to one or more antibiotic in clinical use and multi-drug resistant bacteria are causing outbreaks of potentially fatal diseases in hospitals and in the community. Why Was This Study Done? Although epidemiological studies (investigations of the causes, distribution, and control of disease in population) show a correlation between antibiotic use and antibiotic resistance in populations, such studies cannot prove that antibiotic use actually causes antibiotic resistance. It could be that the people who use more antibiotics share other characteristics that increase their chance of developing antibiotic resistance (so-called “confounding”). A causal link between antibiotic use and the development of antibiotic resistance can only be established by doing a randomized controlled trial. In such trials, groups of individuals are chosen at random to avoid confounding, given different treatments, and outcomes in the different groups compared. Here, the researchers undertake a randomized clinical trial to assess whether macrolide resistance is higher in communities treated with azithromycin for trachoma than in untreated communities. Azithromycin—an erythromycin derivative—is used to treat common bacterial infections such as middle ear infections caused by Streptococcus pneumoniae. Trachoma—the world's leading infectious cause of blindness—is caused by Chlamydia trachomatis. The World Health Organization's trachoma elimination strategy includes annual azithromycin treatment of at-risk communities. What Did the Researchers Do and Find? In this cluster-randomized trial (a study that randomly assigns groups of people rather than individuals to different treatments), 12 Ethiopian communities received mass azithromycin treatment of children aged 1–10 years old at 0, 3, 6, and 9 months, and 12 control communities received the antibiotic only at 12 months. The researchers took nasopharyngeal (nose and throat) swabs from randomly selected treated children at 0 and 12 months and from randomly selected control children at 12 months. They isolated S. pneumoniae from the swabs and tested the isolates for antibiotic susceptibility. 70%–80% of the children tested had S. pneumoniae in their nose or throat. In the treated group, 3.6% of monitored children were carrying azithromycin-resistant S. pneumoniae at 0 months, whereas 46.9% were doing so at 12 months—a statistically significant increase. Only 9.2% of the monitored children in the untreated group were carrying azithromycin-resistant S. pneumoniae at 12 months, a significantly lower prevalence than in the treated group. Importantly, there was no resistance to penicillin in any S. pneumoniae isolates obtained from the treated children at 0 or 12 months; one penicillin-resistant isolate was obtained from the control children. What Do These Findings Mean? These findings indicate that macrolide resistance is higher in nasopharyngeal S. pneumoniae in communities receiving intensive azithromycin treatment than in untreated communities. Thus, they support the idea that frequent antibiotic use selects for antibiotic resistance in populations. Although the study was undertaken in Ethiopian communities with high rates of nasopharyngeal S. pneumoniae carriage, this finding is likely to be generalizable to other settings. Importantly, these findings have no bearing on current trachoma control activities, which use less frequent antibiotic treatments and are less likely to select for azithromycin resistance. The lack of any increase in penicillin resistance, which is usually the first-line therapy for S. pneumoniae infections, is also reassuring. However, although these findings suggest that the benefits of mass azithromycin treatment for trachoma outweigh any potential adverse affects, they nonetheless highlight the importance of continued monitoring for the secondary effects of mass antibiotic distributions. Additional Information Please access these Web sites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1000377. The Bugs and Drugs website provides information about antibiotic resistance and links to other resources The US National Institute of Allergy and Infectious Diseases provides information on antimicrobial drug resistance and on diseases caused by S. pneumoniae (pneumococcal diseases) The US Centers for Disease Control and Prevention also have information on antibiotic resistance (in English and Spanish) The World Health Organization has information about the global threat of antimicrobial resistance and about trachoma (in several languages) More information about the trial described in this paper is available on ClinicalTrials.gov

After 6 biannual mass distributions of oral azithromycin for trachoma in Ethiopian communities, 76.8% (95% confidence interval [CI], 66.3%-85.1%) of nasopharyngeal Streptococcus pneumoniae isolates from children aged 1-5 years were resistant to macrolides. Twelve and 24 months after the last azithromycin treatment, resistance decreased to 30.6% (95% CI, 18.8%-40.4%; P

It is unclear how the prevalence of clinically active trachoma correlates with the prevalence of ocular chlamydial infection at the community level. In 24 villages from a cluster-randomized clinical trial of mass azithromycin distributions in Ethiopia, the correlation between the prevalence of clinical activity (on examination) and chlamydial infection (by polymerase chain reaction) was moderately strong before mass antibiotic treatments (Pearson's correlation coefficient r = 0.75, 95% confidence interval [CI] = 0.52–0.87), but decreased at each time point during four biannual treatments (at 24 months, r = 0.15, 95% CI = −0.14–0.41). One year after the final treatment, the correlation coefficient had increased, but not to the pre-treatment level (r = 0.55, 95% CI = 0.30–0.73). In a region with hyperendemic trachoma, conjunctival examination was a useful indicator of the prevalence of chlamydial infection before treatments, less useful during mass treatments, but regained utility by one year after treatments had stopped.

This work addresses two major issues relating to Helium Ion Microscopy (HeIM). First we show that HeIM is capable of solving the interpretation difficulties that arise when complex three-dimensional structures are imaged using traditional high lateral resolution techniques which are transmission based, such as scanning transmission electron microscopy (STEM). Secondly we use a nano-composite coating consisting of amorphous carbon embedded in chromium rich matrix to estimate the mean escape depth for amorphous carbon for secondary electrons generated by helium ion impact as a measure of HeIM depth resolution.

TiAlN/VN multilayer coatings exhibit excellent dry sliding wear resistance and low friction coefficient, reported to be associated with the formation of self-lubricating V2O5. To investigate this hypothesis, dry sliding ball-on-disc wear tests of TiAlN/VN coatings on flat stainless steel substrates were undertaken against Al2O3 at 25 C, 300 C and 635 C in air. The coating exhibited increased wear rate\ud with temperature. The friction coefficient was 0.53 at 25 C, which increased to 1.03 at 300 C and decreased to 0.46 at 635 C. Detailed investigation of the worn surfaces was undertaken using site-specific transmission electron microscopy (TEM) via focused ion beam (FIB) microscopy, along with Fourier transform infrared (FTIR) and Raman spectroscopy. Microstructure and tribo-induced chemical\ud reactions at these temperatures were correlated with the coating’s wear and friction behaviour. The friction behaviour at room temperature is attributed to the presence of a thin hydrated tribofilm and the presence of V2O5 at high temperature.

Context Mass oral azithromycin distribution to affected communities is a cornerstone of the World Health Organization's trachoma elimination program. Antibiotics are provided to target the ocular strains of chlamydia that cause trachoma, but may also be efficacious against respiratory disease, diarrhea, and malaria—frequent causes of childhood mortality in trachoma-endemic areas. Objective To compare mortality rates of participants aged 1 to 9 years in treated communities with those in untreated communities. Design, Setting, and Participants We conducted a cluster-randomized clinical trial of mass azithromycin administration for trachoma control. Forty-eight communities (known as subkebeles) were randomized into 1 of 3 treatment schedules (annual treatment of all residents [15 902 participants], biannual treatment of all residents [17 288 participants], or quarterly treatment of children only [14 716 participants]) or into 1 group for which treatment was delayed by 1 year (control, 18 498 participants). Twelve subkebeles were randomized to each of the 4 schedules with all children in each of the 3 communities being eligible for treatment. The trial was conducted in a field setting in rural Ethiopia, May 2006 to May 2007. Interventions A single dose of oral azithromycin (adults, 1 g; children, 20 mg/kg) was administered for treatment of ocular Chlamydia trachomatis infection. Antibiotic coverage levels for children aged 1 to 9 years exceeded 80% at all visits. Main Outcome Measure The main outcome measure was the community-specific mortality risk for children aged 1 to 9 years over the course of 1 year. Mortality was measured by enumerative census at baseline and again after 1 year. Comparison of the risk of mortality was a prespecified outcome for the clinical trial. Results The odds ratio for childhood mortality in the intervention communities was 0.51 (95% confidence interval, 0.29-0.90; P = .02; clustered logistic regression) compared with the control group. In the treated communities, the estimated overall mortality rate during this period for children aged 1 to 9 years in the untreated group was 8.3 per 1000 person-years (95% confidence interval, 5.3-13.1), while among the treated communities, the estimated overall mortality rate was 4.1 per 1000 person-years (95% confidence interval, 3.0-5.7) for children aged 1 to 9 years. Conclusion In a trachoma-endemic area, mass distribution of oral azithromycin was associated with reduced mortality in children. Trial Registration clinicaltrials.gov Identifier: NCT00322972

Background As part of the SAFE strategy, mass antibiotic treatments are useful in controlling the ocular strains of chlamydia that cause trachoma. The World Health Organization recommends treating at least 80% of individuals per community. However, the role of antibiotic coverage for trachoma control has been poorly characterized. Methodology/Principal Findings In a collection of cluster-randomized clinical trials, mass oral azithromycin was administered to 40 villages in Ethiopia. The village prevalence of ocular chlamydia was determined before treatment, and at two and six months post-treatment. The mean prevalence of ocular chlamydia was 48.9% (95% CI 42.8 to 55.0%) before mass treatments, decreased to 5.4% (95% CI 3.9 to 7.0%) at two months after treatments (p, Author Summary Trachoma, caused by ocular chlamydia infection, is the most common infectious cause of blindness in the world. The World Health Organization (WHO) recommends the SAFE strategy (eyelid surgery, antibiotics, facial hygiene, environmental improvements) for trachoma control. Oral antibiotics reduce the transmission of ocular chlamydia, but re-infection of treated individuals is common. Therefore, the WHO recommends annual mass antibiotic treatments to the entire village. The success of treatment is likely based on many factors, including the antibiotic coverage, or percentage of villagers who receive antibiotics. However, no studies have analyzed the importance of antibiotic coverage for the reduction of ocular chlamydia. Here, we performed multivariate regression analyses on data from a clinical trial of mass oral antibiotics for trachoma in a severely affected area of Ethiopia. At the relatively high levels of antibiotic coverage in our study, coverage was associated with post-treatment infection at two months, but not at six months. The amount of infection at baseline was strongly correlated with post-treatment infection at both two and six months. These results suggest that in areas with severe trachoma treated with relatively high antibiotic coverage, increasing coverage even further may have only a short-term benefit.

We investigated antimicrobial drug resistance in ocular Chlamydia trachomatis 18 months after 4 biannual communitywide distributions of antimicrobial drugs in a region of Ethiopia where ocular strains of C. trachomatis are highly endemic. We found no significant differences in susceptibilities to azithromycin and doxycycline in 6 posttreatment and 4 pretreatment samples.

Summary Background Trachoma-control programmes distribute oral azithromycin to treat the ocular strains of chlamydia that cause the disease and to control infection. Theoretically, elimination of infection is feasible if untreated individuals receive an indirect protective effect from living in repeatedly treated communities, which is similar to herd protection in vaccine programmes. We assessed indirect protection against trachoma with mass azithromycin distributions. Methods In a cluster randomised trial, 24 subkebeles (government-defined units) in Amhara, Ethiopia, were randomised, with use of a simple random sample, to distribution four times per year of single-dose oral azithromycin to children aged 1–10 years (12 subkebeles, 4764 children), or to delayed treatment until after the study (control; 12 subkebeles, 6014 children). We compared the prevalence of ocular chlamydial infection in untreated individuals 11 years and older between baseline and 12 months in the treated subkebeles, and at 12 months between the treated and control subkebeles. Health-care and laboratory personnel were blinded to study group. Analysis was intention to treat. The study is registered with clinicaltrials.gov, number NCT00322972. Findings At 12 months, 637 children aged 1–10 years and 561 adults and children aged 11 years and older were analysed in the children-treated group, and 618 and 550, respectively, in the control group. The mean prevalence of infection in children decreased from 48·4% (95% CI 42·9–53·9) to 3·6% (0·8–6·4) after four mass treatments. At 12 months, the mean prevalence of infection in the untreated age group (≥11 years) was 47% (95% CI 33–57) less than baseline (p=0·002), and 35% (95% CI 1–57) less than that in untreated communities (p=0·04). Interpretation Frequent treatment of children, who are a core group for transmission of trachoma, could eventually eliminate infection from the entire community. Herd protection is offered by repeated mass antibiotic treatments, providing a strategy for elimination of a bacterial disease when an effective vaccine is unavailable. Funding National Institutes of Health.

Background Antibiotics are a major tool in the WHO's trachoma control program. Even a single mass distribution reduces the prevalence of the ocular chlamydia that causes trachoma. Unfortunately, infection returns after a single treatment, at least in severely affected areas. Here, we test whether additional scheduled treatments further reduce infection, and whether infection returns after distributions are discontinued. Methods Sixteen communities in Ethiopia were randomly selected. Ocular chlamydial infection in 1- to 5-year-old children was monitored over four biannual azithromycin distributions and for 24 months after the last treatment. Findings The average prevalence of infection in 1- to 5-year-old children was reduced from 63.5% pre-treatment to 11.5% six months after the first distribution (P, Author Summary Trachoma is one of the leading causes of blindness in the developing world. The World Health Organization has a multi-pronged approach to controlling the ocular chlamydial infection that causes the disease, including distributing antibiotics to entire communities. Even a single community treatment dramatically reduces the prevalence of the infection. Unfortunately, infection returns back into communities after treatment, at least in severely affected areas such as rural Ethiopia. Here, we assess whether additional scheduled treatments in 16 communities in the Gurage area of Ethiopia further reduce infection, and whether the disease returns after distributions are stopped. In communities with the highest levels of trachoma ever studied, we find that repeated mass oral azithromycin distributions gradually reduce the prevalence of trachoma infection in a community, as long as these treatments are given frequently enough and to enough people in the community. Unfortunately, infection returns into the communities after the last treatment. Sustainable changes or complete local elimination of infection will be necessary to stop the return of ocular chlamydial in communities with very high prevalence of the disease.

Objective To determine whether infectious trachoma can be completely eliminated from severely affected villages. Design Cross-sectional survey of 2 villages previously enrolled and monitored over 42 months as part of a larger, group-randomized clinical trial. Participants A total of 758 individuals residing in 2 villages with high baseline trachoma prevalence, of a total population of 768 (98.7%). Methods All members of the 2 villages were offered 6 biannual mass treatments with oral azithromycin. At 42 months, each current village member was examined. The right upper tarsal conjunctiva was everted and swabbed. Samples were processed for evidence of Chlamydia trachomatis RNA. Main Outcome Measures Clinical activity by World Health Organization simplified grading scale for trachoma and laboratory evidence of chlamydial RNA. Results Average antibiotic coverage over the study period was 90% and 94% in the 2 villages. Clinical trachoma activity in children aged 1 to 5 years decreased from 78% and 83% in the 2 villages before treatment to 17% and 24% at 42 months. Polymerase chain reaction (PCR) evidence of infection in the same age group decreased from 48% to 0% in both villages at 42 months. When all age groups were examined, there were zero cases with evidence of chlamydial RNA among 758 total villagers tested. Conclusions Biannual mass distribution of azithromycin can locally eliminate ocular chlamydial infection from severely affected communities. Financial Disclosure(s) The author(s) have no proprietary or commercial interest in any materials discussed in this article.

A field study was carried out in Shanghai metro stations to gather and evaluate information about the real environment. The thermal environment and particulate matter levels were monitored in this study. The mean thermal sensation vote in metro stations was 0.91, and the mean thermal neutral temperature was 20.6 degrees C. Although 92.1% of subjects voted that the thermal environment was acceptable, the condition of air quality in Shanghai metro stations was not good. The mean levels of PM1.0, PM2.5, and PM10 were 0.231+/-0.152, 0.287+/-0.177, and 0.366+/-0.193 mg/m3, respectively. The contribution of PM1.0 to PM2.5 and PM2.5 to PM10 was up to 79% and 76%, respectively. This means that fine particles or ultrafine particles constituted the preponderant part of metro station particulate matter.

Carbon based coatings have attracted considerable interest in a wide range of industries due to their excellent tribological properties. Nanoscale hydrogen free C/Cr coatings have been produced by unbalanced magnetron (UBM) sputtering [1]. Their structure and properties are strongly influenced by the deposition bias voltage [1–2]. The multilayer structure at −350V substrate bias is believed to be a result of phase separation and formation of a self-organised layered nanostructure in conditions of high ion irradiation and elemental diffusion [2].

PURPOSE. Trachoma remains the leading infectious cause of blindness worldwide. The World Health Organization (WHO) recommends mass antibiotic distributions in its strategy to eliminate blinding trachoma. To determine the most effective antibiotic treatment strategy, it is essential to have a diagnostic test that can correctly measure the true status of ocular Chlamydia trachomatis infection in individuals, particularly after treatment. A newer ribosomal ribonucleic acid (rRNA)-based amplification test was compared with the current DNA-based polymerase chain reaction (PCR) for the detection of C. trachomatis. METHODS. An rRNA-based assay and PCR were performed on swab specimens taken from the right upper tarsal conjunctiva of 240 children aged 1 to 5 years living among 16 endemic villages in the Gurage Zone, Ethiopia. RESULTS. The rRNA-based test detected ocular C. trachomatis infection in 142 (59%) subjects compared with 67 (28%) detected by PCR (McNemar's test, P < 0.0001). The rRNA-based test gave positive results for all subjects who were positive by PCR and detected infection in 75 (31%) additional subjects. CONCLUSIONS. The rRNA-based test appears to have significantly greater sensitivity than PCR for the detection of ocular C. trachomatis infection in children in trachoma-endemic villages. The increased sensitivity of the rRNA-based test may be due to its ability to detect low levels of C. trachomatis infection in individuals, which can occur especially after antibiotic treatment. Data from past studies in which PCR was used to assess the prevalence of infectious trachoma after community-wide antibiotic treatments could have underestimated the true prevalence of infection.

International audience; The chemical and physical structure of a TiAlN/VN multilayer, of average layer thickness 3.4±0.4 nm, was characterised using a spherical aberration corrected STEM, utilising a nominal 0.1nm beam, by HAADF and EELS. The interface between layers was shown to be rough, with local thickness variations evident in layer thickness. Chemical mixing between layers was identified, consistent with numerical modelling of the deposition flux and layer growth. The implications of the compositional modulation are discussed.

There are various approaches to control trachoma. These include the elimination of the ocular strains of Chlamydia trachomatis that cause the disease and to decrease the spread of infection by other measures such as fly control. Here, we examined how these two are related (i.e., how treating children with antibiotics affects carriage of Chlamydia by flies). Flies were collected in villages that had received mass oral azithromycin distribution and were compared with flies in untreated villages. Polymerase chain reaction (PCR) was performed to detect chlamydial DNA on the flies. Conjunctival swabs were also taken to assay for chlamydial prevalence in the children. Chlamydia was found on 23% of the flies in the untreated villages but only 0.3% in treated villages. Prevalence of trachoma in children proved to be an excellent predictor of the prevalence on flies (correlation coefficient, 0.89). Thus, treating children with antibiotics may drastically reduce the role of flies as a vector.

Reciprocating (ball on flat) dry sliding wear tests of TiAlN/VN and CrN/NbN multilayer coatings were undertaken under ambient conditions with either an alumina or tungsten carbide counterface. Wear rates were found to be in the mild wear regime. Worn surfaces and wear debris were examined by using scanning electron microscopy (SEM) and Fourier transformed infrared (FTIR) microscopy. Surface smoothing by the wear process was associated with wear debris with a roll shape, which adhered to the worn surface. Analysis of wear debris suggests they are probably hydrated. The properties of the tribofilm and rolls are correlated with the friction.

Background/Aim: The World Health Organisation (WHO) hopes to achieve global elimination of trachoma, still the leading cause of preventable blindness worldwide, in part through mass antibiotic treatment. DNA-based nucleic acid amplification tests (NAATs) are currently used to evaluate the success of treatment programmes by measuring the prevalence of C trachomatis infection. Some believe that newer ribosomal RNA (rRNA)-based tests may be much more sensitive since bacterial rRNA is present in amounts up to 10 000 times that of genomic DNA. Others believe that rRNA-based tests are instead less sensitive but more specific, due to the presence of dead or subviable organisms that the test may not detect. This study compares an rRNA-based test to a DNA-based test for the detection of ocular C trachomatis infection in children living in trachoma-endemic villages. Methods: An rRNA-based amplification test and DNA-based polymerase chain reaction (PCR) were performed on swab specimens taken from the right upper tarsal conjunctiva of 56 children aged 0–10 years living in two villages in Amhara, Ethiopia. Results: The rRNA-based test detected ocular C trachomatis infection in 35 (63%) subjects compared with 22 (39%) detected by PCR (McNemar’s test, p = 0.0002). The rRNA-based test gave positive results for all subjects that were positive by PCR, and also detected infection in 13 (23%) additional subjects. Conclusion: The rRNA-based test appears to have significantly greater sensitivity than PCR for the detection of ocular chlamydial infection in children in trachoma-endemic villages. Using the rRNA-based test, we may be able to detect infection that was previously missed with PCR. Past studies using DNA-based tests to assess prevalence of infectious trachoma following antibiotic treatment may have underestimated the true prevalence of infection.

TiAlN/VN multilayer coatings exhibit excellent dry sliding wear resistance and low friction coefficient, believed to be associated with the formation of tribo-films comprising Magnéli phases such as V2O5. In order to investigate this hypothesis, dry sliding wear of TiAlN/VN coatings was undertaken against Al2O3. Focused ion beam was used to generate site-specific TEM specimens. A thin (2-20nm) tribo-film was observed at the worn surface, with occasional 'roll-like' wear debris (φ 5-40nm). Both were amorphous and contained the same Ti, Al and V ratio as the coating, but with the nitrogen largely replaced by oxygen. No evidence of Magnéli phases was found. © 2006 IOP Publishing Ltd.