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Politically neutral pedagogy is often the subject of both praise and condemnation. But treating political neutrality as a principle to be either embraced or rejected confuses the issue, because the permissibility of neutrality actually varies across educational contexts. Educational practice should not be evaluated on the basis of whether or not it is politically neutral, but in terms of the specific burdens it places on individual interests. Contractualism, as an account of moral permissibility, is well-suited to the task of identifying when, and why, educators may permissibly aspire to politically neutral pedagogy. In particular, it identifies judicious adherence to political neutrality as a practical classroom approach to preventing legislative interference with permissible non-neutrality.

Objectives: To determine if maternal prenatal infection increases risk of offspring postnatal infections through age 5 or diagnosis of respiratory allergy at age 5, independent of prenatal/postnatal antibiotic exposure. To evaluate if frequency of offspring infections mediates an association between prenatal infection and respiratory allergy at age 5. Study design: Secondary data analyses were performed from the Child Health and Development Studies (CHDS), a prospective, longitudinal birth cohort that enrolled pregnant women from 1959 to 1966 (N = 19,044 live births). The sample included a subset of mother-offspring dyads (n = 2062) with abstracted medical record data from the prenatal period through age 5 that included information on antibiotic use, infection, and offspring respiratory allergy. Results: Second trimester maternal infection was associated with an increased risk of offspring infection (IRR = 1.23; 95% CI = 1.09–1.39; p = 0.001). No significant direct associations were detected between prenatal infection and diagnosis of offspring respiratory allergy. Offspring infection (OR = 1.17; 95% CI = 1.13–1.20; p

In April–July 2008, intensive measurements were made of atmospheric composition and chemistry in Sabah, Malaysia, as part of the "Oxidant and particle photochemical processes above a South-East Asian tropical rainforest" (OP3) project. Fluxes and concentrations of trace gases and particles were made from and above the rainforest canopy at the Bukit Atur Global Atmosphere Watch station and at the nearby Sabahmas oil palm plantation, using both ground-based and airborne measurements. Here, the measurement and modelling strategies used, the characteristics of the sites and an overview of data obtained are described. Composition measurements show that the rainforest site was not significantly impacted by anthropogenic pollution, and this is confirmed by satellite retrievals of NO2 and HCHO. The dominant modulators of atmospheric chemistry at the rainforest site were therefore emissions of BVOCs and soil emissions of reactive nitrogen oxides. At the observed BVOC:NOx volume mixing ratio (~100 pptv/pptv), current chemical models suggest that daytime maximum OH concentrations should be ca. 105 radicals cm−3, but observed OH concentrations were an order of magnitude greater than this. We confirm, therefore, previous measurements that suggest that an unexplained source of OH must exist above tropical rainforest and we continue to interrogate the data to find explanations for this.

Large-grain Nb has become a viable alternative to fine-grain Nb for the fabrication of superconducting radio-frequency cavities. In this contribution we report the results from a heat treatment study of a large-grain 1.5 GHz single-cell cavity made of “medium purity” Nb. The baseline surface preparation prior to heat treatment consisted of standard buffered chemical polishing. The heat treatment in the range 800–1400°C was done in a newly designed vacuum induction furnace. Q_{0} values of the order of 2×10^{10} at 2.0 K and peak surface magnetic field (B_{p}) of 90 mT were achieved reproducibly. A Q_{0} value of (5±1)×10^{10} at 2.0 K and B_{p}=90 mT was obtained after heat treatment at 1400°C. This is the highest value ever reported at this temperature, frequency, and field. Samples heat treated with the cavity at 1400°C were analyzed by secondary ion mass spectrometry, x-ray photoelectron spectroscopy, energy dispersive x ray, point-contact tunneling, and x-ray diffraction, and revealed a complex surface composition which includes titanium oxide, increased carbon, and nitrogen content but reduced hydrogen concentration compared to a non-heat-treated sample.

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Objective: To assess whether psychosocial factors moderate the associations between neighborhood disadvantage and incident heart failure (HF). Methods: Among 1448 Non-Hispanic (NH) Black persons dually enrolled in two community-based cohorts in Jackson, Mississippi who were free of HF as of January 1, 2000, 336 HF events classified by reviewer panel accrued through December 31, 2017. Multilevel, multivariable Cox regression models were used to examine whether optimism and negative affect moderated the associations of two measures of neighborhood characteristics (the national Area Deprivation Index (ADI) and perceived neighborhood problems) on incident hospitalized HF. Results: Optimism moderated the association of the ADI with incident HF. Compared to participants reporting the lowest tertile of optimism, those in the highest tertile of optimism had a 29% lower rate of HF associated with increasing ADI in fully adjusted models. We found no evidence for a moderating effect of negative affect. Conclusions: This study supports optimism as a source of resilience to the detrimental effects of neighborhood disadvantage on HF risk. Population-level strategies to promote sociocultural antecedents to optimism may serve as a viable method of reducing the disproportionate burden of HF among NH Black persons.

Meeting the current demand for STEM graduates requires significantly increasing the number of students majoring in STEM fields. One program designed to increase the number of STEM majors is Project Lead The Way (PLTW). Using statewide data from Indiana, this research examined the effects of PLTW participation in high school on the likelihood of majoring in STEM during college. Propensity score matching and weighting were used to provide a rigorous evaluation of PLTW that would allow causal inferences to be made about program effectiveness. Results indicated that PLTW participation significantly increased the likelihood that students who attend college will major in a STEM discipline. The results also indicated a dosage effect for PLTW participation. Specifically, completing one PLTW course increased the likelihood of majoring in STEM by 0.16, and completing two PLTW courses increased the likelihood of majoring in STEM by 0.27. Completing three or more PLTW courses increased the likelihood of majoring in STEM by 0.38. Tests of the conditional independence assumption also revealed that it was unlikely that these results were the product of external, unmeasured variables. Thus, it appears likely that PLTW participation has a direct, causal effect on majoring in a STEM discipline during college.

A microfiber interferometer based on a single-mode tapered-no-core single-mode (STNCS) fiber structure coated with a thin layer of graphene oxide (GO) was proposed and demonstrated as a relative humidity (RH) sensor. The STNCS fiber structure has a strong evanescent field, which can sensitively response to changes in the surrounding refractive index. The moisture-sensitive material GO was used to form the film on the no-core fiber by a dip impregnation method. The effects of GO concentration and the tapered waist diameter on RH sensitivity were studied experimentally. The experimental results showed that a thinner waist diameter provides higher RH sensitivity. When the concentration of GO solution is 0.01 mg/mL, the STNCS fiber structure with a waist diameter of 2.9 μm performs better in RH sensing; a high sensitivity of 0.461 nm/%RH in the range of 40-98% was achieved. The sensor has good stability with wavelength fluctuations of ±0.009 nm and ±0.008 nm over 60 mins at RHs of 50% and 80%, respectively. The proposed fiber optic humidity sensor has a high sensitivity over a wide measurement range and offers good stability showing promising potential application in the field of RH sensing.

Recent research and critiques of affirmative action in college admissions raise questions about popular approaches for enhancing learning outcomes, suggesting that a diverse student body is neither a necessary nor a sufficient condition for experiencing diversity, creating supportive learning environments, or fostering desired outcomes of college. This study found that the diversity of a student body was positively related to interactions among students from different backgrounds but not meaningfully related to the degree to which the campus was perceived as supportive. Institutional characteristics were also related to diversity outcomes. [ABSTRACT FROM AUTHOR]

Objectives: During 2003, the Health Protection Agency''s Antibiotic Resistance Monitoring and Reference Laboratory began to receive isolates of Escherichia coli for confirmation of extended-spectrum β-lactamase production with a phenotype implying a CTX-M-type β-lactamase, i.e. MICs of cefotaxime ≥8-fold higher than MICs of ceftazidime. Many were referred as being from community patients. We examined 291 CTX-M-producing isolates from the UK and investigated the genetic basis of their phenotype.Methods: PCR was used to detect alleles encoding CTX-M enzymes and to assign these to their blaCTX-M phylogenetic groups. Selected alleles were sequenced. Producers were compared by analysis of banding patterns generated by pulsed-field gel electrophoresis of XbaI-digested genomic DNA. MICs were determined by an agar dilution method or by Etest.Results: Of 291 CTX-M-producing E. coli isolates studied from 42 UK centres, 70 (24%) were reportedly from community patients, many of whom had only limited recent hospital contact. Community isolates were referred by 12 centres. Two hundred and seventy-nine (95.9%) producers contained genes encoding group 1 CTX-M enzymes and 12 contained blaCTX-M-9-like alleles. An epidemic CTX-M-15-producing strain was identified, with 110 community and inpatient isolates referred from six centres. Representatives of four other major strains also produced CTX-M-15, as did several sporadic isolates examined. Most producers were multi-resistant to fluoroquinolones, trimethoprim, tetracycline and aminoglycosides as well as to non-carbapenem β-lactams.Conclusions: CTX-M-producing E. coli are a rapidly developing problem in the UK, with CTX-M-15 particularly common. The diversity of producers and geographical scatter of referring laboratories indicates wide dissemination of blaCTX-M genes. Because of the public health implications, including for the treatment of community-acquired urinary tract infections, the spread of these strains—and CTX-M-15 β-lactamase in particular—merits close monitoring. [ABSTRACT FROM AUTHOR]

SUMMARY: Preclinical studies have identified numerous neuroprotective drugs that attenuate brain damage and improve functional outcome after cerebral ischemia. Despite this success in animal models, neuroprotective therapies in the clinical setting have been unsuccessful. Identification of biochemical markers common to preclinical and clinical cerebral ischemia will provide a more sensitive and objective measure of injury severity and outcome to facilitate clinical management and treatment. However, there are currently no effective biomarkers available for assessment of stroke. Nonerythroid αII-spectrin is a cytoskeletal protein that is cleaved by calpain and caspase-3 proteases to signature αII-spectrin breakdown products (αII-SBDPs) after cerebral ischemia in rodents. This investigation examined accumulation of calpain- and caspase-3-cleaved αII-SBDPs in cerebrospinal fluid (CSF) of rodents subjected to 2 hours of transient focal cerebral ischemia produced by middle cerebral artery occlusion (MCAO) followed by reperfusion. After MCAO injury, full-length αII-spectrin protein was decreased in brain tissue and increased in CSF from 24 to 72 hours after injury. Whereas αII-SBDPs were undetectable in sham-injured control animals, calpain but not caspase-3 specific αII-SBDPs were significantly increased in CSF after injury. However, caspase-3 αII-SBDPS were observed in CSF of some injured animals. These results indicate that αII-SBDPs detected in CSF after injury, particularly those mediated by calpain, may be useful diagnostic indicators of cerebral infarction that can provide important information about specific neurochemical events that have occurred in the brain after acute stroke. [ABSTRACT FROM AUTHOR]

Cadmium sulphide can be templated on λ-DNA molecules to form an aqueous dispersion of CdS/λ-DNA nanowires. Subsequent addition of ethylene glycol to 50% v/v is sufficient to formulate an ink suitable for printing using piezoelectric drop-on-demand technology. Printed droplet arrays show a coffee-ring morphology of individual deposits by fluorescence and Raman microscopy, but upon increasing the number of layers of printed material by repeated printing over each droplet, the dry deposit approaches closer to a disc shape. It is also possible to print parallel tracks by reducing the droplet separation in the array until neighbouring droplets overlap before they dry. The droplets coalesce to form a strip of width roughly equal to the diameter of the droplets. Evaporation-driven capillary flow sends the nanowires to the edges of the strip and when dry they form parallel tracks of CdS/λ-DNA nanowire bundles. Both droplets and tracks were printed onto Pt-on-glass interdigitated microelectrodes (10 μm width, 10 μm gap). The current–voltage characteristics of these two-terminal devices were approximately ohmic, but with some hysteresis. The conductance increased with temperature as a simple activated process with activation energies of 0.57 ± 0.02 eV (tracks) and 0.39 ± 0.02 eV (droplets). The impedance spectra of the printed films were consistent with hopping between CdS grains. [ABSTRACT FROM AUTHOR]

Poly(styrene)-block-poly(dimethylsiloxane) (PS-b-PDMS) is an excellent block copolymer (BCP) system for self-assembly and inorganic template fabrication because of its high Flory–Huggins parameter (χ ∼ 0.26) at room temperature in comparison to other BCPs, and high selective etch contrast between PS and PDMS block for nanopatterning. In this work, self-assembly in PS-b-PDMS BCP is achieved by combining hydroxyl-terminated poly(dimethylsiloxane) (PDMS-OH) brush surfaces with solvent vapor annealing. As an alternative to standard brush chemistry, we report a simple method based on the use of surfaces functionalized with silane-based self-assembled monolayers (SAMs). A solution-based approach to SAM formation was adopted in this investigation. The influence of the SAM-modified surfaces upon BCP films was compared with polymer brush-based surfaces. The cylinder forming PS-b-PDMS BCP and PDMS-OH polymer brush were synthesized by sequential living anionic polymerization. It was observed that silane SAMs provided the appropriate surface chemistry which, when combined with solvent annealing, led to microphase segregation in the BCP. It was also demonstrated that orientation of the PDMS cylinders may be controlled by judicious choice of the appropriate silane. The PDMS patterns were successfully used as an on-chip etch mask to transfer the BCP pattern to underlying silicon substrate with sub-25 nm silicon nanoscale features. This alternative SAM/BCP approach to nanopattern formation shows promising results, pertinent in the field of nanotechnology, and with much potential for application, such as in the fabrication of nanoimprint lithography stamps, nanofluidic devices or in narrow and multilevel interconnected lines. [ABSTRACT FROM AUTHOR]