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Summary: This review of 19 studies (39,783 patients) of atrial fibrillation after thoracic surgery addresses the pathophysiology, incidence, and consequences of atrial fibrillation in this population, as well as its prevention and management. Interestingly, atrial fibrillation was most often identified in patients not previously known to have the disease. Rhythm control with amiodarone was the most commonly used treatment and nearly all patients were discharged in sinus rhythm. Major predictors were age; male sex; history of atrial fibrillation; congestive heart failure; left atrial enlargement; elevated brain natriuretic peptide level; and the invasiveness of procedures. Overall, patients with atrial fibrillation stayed 3 days longer in hospital. We also discuss the importance of standardising research on this subject and provide recommendations that might mitigate the impact postoperative atrial fibrillation on hospital resources. [ABSTRACT FROM AUTHOR]

Objective: To investigate the association between obstetric haemorrhage and cardiovascular disease up to three decades after pregnancy.Design: Population-based cohort study.Setting and Population: All women who delivered between 1989 and 2016 in Quebec, Canada.Methods: Using hospital admissions data, 1 224 975 women were followed from their first delivery until March 2018. The main exposure measures were antenatal (placenta praevia, placental abruption, peripartum haemorrhage) or postpartum haemorrhage, with or without transfusion. Adjusted Cox regression models were used to assess the association between obstetric haemorrhage and future cardiovascular disease.Main Outcome Measure: Cardiovascular hospitalisation.Results: Among 104 291 (8.5%) women with haemorrhage, 4612 (4.4%) required transfusion. Women with haemorrhage had a higher incidence of cardiovascular hospitalisation than women without haemorrhage (15.5 versus 14.1 per 10 000 person-years; 2437 versus 28 432 events). Risk of cardiovascular hospitalisation was higher for obstetric haemorrhage, with or without transfusion, compared with no haemorrhage (adjusted hazard ratio [aHR] 1.06, 95% CI 1.02-1.10). Women with haemorrhage and transfusion had a substantially greater risk of cardiovascular hospitalisation (aHR 1.47, 95% CI 1.23-1.76). Among transfused women, placental abruption (aHR 1.79, 95% CI 1.06-3.00) and postpartum haemorrhage (aHR 1.38, 95% CI 1.13-1.68) were both associated with risk of cardiovascular hospitalisation. Antenatal haemorrhage with transfusion was associated with 2.46 times the risk of cardiovascular hospitalisation at 5 years (95% CI 1.59-3.80) and 2.14 times the risk at 10 years (95% CI 1.47-3.12).Conclusions: Obstetric haemorrhage requiring transfusion is associated with maternal cardiovascular disease. The benefit of cardiovascular risk prevention in pregnant women with obstetric haemorrhage requires further investigation.Tweetable Abstract: Risk of future cardiovascular disease is increased for women with obstetric haemorrhage who require transfusion. [ABSTRACT FROM AUTHOR]

The spatial distribution of CdTe nanoparticles within a ZnO thin-film matrix was manipulated using a dual-source, sequential radio-frequency (RF)-sputter deposition technique to produce nanocomposite materials with tuned spectral absorption characteristics. The relative substrate exposure time to each sputtering source was used to control the semiconductor phase connectivity, both within the film plane and along the film growth direction, to influence the degree of photocarrier confinement and the resulting optical transition energies exhibited by the CdTe phase. Significant changes (up to ΔE ≈ 0.3 eV) in the absorption onset energy for the CdTe nanoparticle ensemble were produced through modification in the extended structure of the semiconductor phase. Raman spectroscopy, cross-sectional transmission electron microscopy, and x-ray diffraction were used to confirm the phase identity of the CdTe and ZnO and to characterize the nanostructures produced in these composite films. Isochronal annealing for 5 min at temperatures up to 800 °C further indicated the potential to improve film crystallinity as well as to establish the post-deposition thermal processing limits of stability for the semiconductor phase. The study highlights the significance of ensemble behavior as a means to influence quantum-scale semiconductor optical characteristics of import to the use of such materials as the basis for a variety of optoelectronic devices, including photosensitized heterojunction components in thin film photovoltaics. [ABSTRACT FROM AUTHOR]

Photoinduced optical absorption changes in the vacuum-ultraviolet (VUV) spectral range have been measured in poly(methylphenylsilylene) thin films under varied excitation photon energies and local atmospheric environments. Spectral changes in resonances associated with both the linear chain Si–Si backbone and the side groups of the hybrid structure are consistent with the photodisruption of backbone topology. These effects are more pronounced under a higher energy photon exposure (5.10 eV) resonant with the fundamental π-π* transition of the phenyl moiety. An aerobic environment also favors more dramatic bleaching of VUV absorption in these materials. Finally, the present study enables a Kramers-Kronig analysis of absorption change from the visible to the VUV. These results do not adequately describe the photoinduced refractive index changes measured at 632.8 nm via ellipsometry, indicating the presence of other contributions to the index modifications observed. [ABSTRACT FROM AUTHOR]

A two-dimensional, lattice-Monte Carlo approach, based upon the energy minimization of an ensemble of electric dipoles, was developed to simulate ferroelectric domain behavior. The model utilizes a Hamiltonian for the total energy based upon electrostatic terms involving dipole–dipole interactions, local polarization gradients, and the influence of applied electric fields. The impact of boundary conditions on the domain configurations obtained was also examined. In general, the model exhibits domain structure characteristics consistent with those observed in a tetragonally distorted ferroelectric. The model was also extended to enable the simulation of ferroelectric hysteresis behavior. Simulated hysteresis loops were found to be very similar in appearance to those observed experimentally in actual materials. This qualitative agreement between the simulated hysteresis loop characteristics and real ferroelectric behavior was also confirmed in simulations run over a range of simulation temperatures and applied field frequencies. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Examines the measurement of quantum-size behavior in semiconductor crystals. Effect of crystal-size distribution and tunneling of the carrier wave functions into the quantum well barrier; Analysis of the microstructure size and absorption edge of cadmium telluride clusters in glass matrix.

Presents a study which reported quantum-confinement-induced shifts in the fundamental absorption edge of isolated CdTe crystallites reported in CdTe-glass composite thin films produced using a sequential rf magnetron sputtering process employing two separate sputtering sources. Observation on translational excitonic confinement; Features of semi-conductor-doped glasses; Physical properties of CdTe-Pyrex composite thin films.

In the United States of America, the western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), is commonly managed with transgenic corn ( Zea mays L.) expressing insecticidal proteins from the bacteria Bacillus thuringiensis Berliner (Bt). Colonies of this pest have been selected in the laboratory on each commercially available transformation event and several resistant field populations have also been identified; some field populations are also resistant. In this study, progeny of a western corn rootworm population collected from a Minnesota corn field planted to SmartStax® corn were evaluated for resistance to corn hybrids expressing Cry3Bb1 (event MON88017) or Cry34/35Ab1 (event DAS-59122-7) and to the individual constituent proteins in diet-overlay bioassays. Results from these assays suggest that this population is resistant to Cry3Bb1 and is incompletely resistant to Cry34/35Ab1. In diet toxicity assays, larvae of the Minnesota ( MN) population had resistance ratios of 4.71 and >13.22 for Cry34/35Ab1 and Cry3Bb1 proteins, respectively, compared with the control colonies. In all on-plant assays, the relative survival of the MN population on the DAS-59122-7 and MON88017 hybrids was significantly greater than the control colonies. Larvae of the MN population had inhibited development when reared on DAS-59122-7 compared with larvae reared on the non-Bt hybrid, indicating resistance was incomplete. Overall, these results document resistance to Cry3Bb1 and an incomplete resistance to Cry34/35Ab1 in a population of WCR from a SmartStax® performance problem field. [ABSTRACT FROM AUTHOR]

Background: Heterotopic ossification (HO) is a debilitating condition that occurs following traumatic injury and may restrict range of motion and delay rehabilitation. The timing and efficacy of surgical resection have varied widely, and there is a gap in knowledge between clinical predictors of HO recurrence and histological analysis.Methods: Thirty-three service members seen at Walter Reed National Military Medical Center for symptomatic HO were enrolled in an institutional review board-approved study. Participants took oxytetracycline on four scheduled days prior to HO resection to determine the mineral apposition rate (bone growth rate).Results: Detailed histological analyses included scanning electron microscopy with backscattered electron imaging and light microscopy. Data indicated that the mineral apposition rate of trauma-induced HO was approximately 1.7 μm/day at the time of operative intervention, which was 1.7 times higher than the rate in non-pathological human bone. The mineral apposition rate and postoperative alkaline phosphatase values were demonstrated to be positively and significantly related (ρ = 0.509, p = 0.026, n = 19). When the analysis was limited to patients with no more than a two-year period from injury to excision (thereby removing outliers who had a longer time period than their counterparts) and traumatic brain injury and nonsteroidal anti-inflammatory drugs (known correlates with HO development) were controlled for in the statistical analysis, the mineral apposition rate and recurrence severity were significantly related (ρ = -0.572, p = 0.041, n = 11).Conclusions: Data demonstrated a link between benchtop research and bedside care, with the mineral apposition rate elevated in patients with HO and correlated with recurrence severity; however, a larger sample size and more clinical factors are needed to refine this model.Level Of Evidence: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence. [ABSTRACT FROM AUTHOR]

Heterotopic ossification (HO) is frequently reported following total joint replacement (TJR) surgery. Symptomatic HO may limit the range of motion, cause pain, and require surgical excision. Deciding an appropriate time for ectopic bone excision is based on clinical judgment, and a more welldefined link between clinical predictors and histological analysis is needed to minimize recurrence. A case series was performed with military healthcare system patients undergoing TJR, who required removal of periarticular ectopic bone. Patients were prescribed oxytetracycline to assess the mineral apposition rate (MAR; ie, bone growth rate) of HO, and excised specimens were analyzed using scanning electron microscopy and light microscopy. Two males and one female were enrolled in this study, with height of 69.0 ± 7.8 inches, weight of 237.7 ± 28.3 pounds, and age of 61 ± 7 years at the time of HO removal. Ectopic bone occurred in two cases following total knee arthroplasty and one total hip arthroplasty. Data indicated that MAR levels were 1.7 times higher than that reported previously for nonpathological human bone (1.7 ± 0.7 μm/day; range: 1.3--2.6 μm/day), and microscopic imaging confirmed that the osseous tissues were still actively remodeling at the time of surgical intervention. Further characterization is needed to optimize HO excision timing and to better understand this pathological bone disorder. [ABSTRACT FROM AUTHOR]

Introduction: Newborn bloodspot screening (NBS) involves testing a small sample of blood taken from the heel of the newborn for a number of serious and life-limiting conditions. In Canada, newborn screening programmes fall under provincial and territorial jurisdiction with no federal coordination. To date, we know very little about the underlying beliefs around different consent practices or how terminology is interpreted by different individuals. Differences in attitudes may have important healthcare consequences. This study will provide empirical data comparing stakeholder opinions on their understanding of consent-related terminology, the perceived applicability of different consent approaches to newborn screening, and the requirements of these different approaches. Methods and analysis: Parents, healthcare professionals and policymakers will be recruited in the provinces of Ontario and Newfoundland and Labrador. Parents will be identified through records held by each provincial screening programme. Healthcare professionals will be purposively sampled on the basis of engagement with newborn screening. Within each province we will identify policymakers who have policy analysis or advisory responsibilities relating to NBS. Data collection will be by qualitative interviews. We will conduct 20 interviews with parents of young children, 10 interviews with key healthcare professionals across the range of appropriate specialties and 10 with policymakers at each site (40 per site, total, N=80). The examination of the transcripts will follow a thematic analysis approach. Recruitment started in June 2014 and is expected to be complete by June 2015. Ethics and dissemination: This study received ethics approval from the Ottawa Health Science Network Research Ethics Board, the Children's Hospital of Eastern Ontario Research Ethics Board (both Ontario), and the Health Research Ethics Authority (Newfoundland and Labrador). Results: These will be reported in peer-reviewed publications and conference presentations. The results will have specific application to the development of parent education materials for newborn screening. [ABSTRACT FROM AUTHOR]

The soybean aphid ( Aphis glycines Matsumura) is a threat to soybean production in the Midwestern United States. Varieties containing the Rag1 soybean aphid resistance gene have been released with limited success in reducing aphid populations. Furthermore, virulent biotypes occur within North America and challenge the durability of single-gene resistance. Pyramiding resistance genes has the potential to improve aphid population suppression and increase resistance gene durability. Our goal was to determine if a pyramid could provide improved aphid population suppression across a wide range of environments.Weconducted a small-plot field experiment across seven states and three years. We compared soybean near-isolines for the Rag1 or Rag2 gene, and a pyramid line containing both genes for their ability to decrease aphid pressure and protect yield compared with a susceptible line. These lines were evaluated both with and without a neonicitinoid seed treatment. All aphid-resistant lines significantly decreased aphid pressure at all locations but one. The pyramid line experienced lower aphid pressure than both single-gene lines at eight of 23 location-years. Soybean aphids significantly reduced soybean yield for the susceptible line by 14% and for both single-gene lines by 5%; however, no significant yield decrease was observed for the pyramid line. The neonicitinoid seed treatment reduced plant exposure to aphids across all soybean lines, but did not provide significant yield protection for any of the lines. These results demonstrate that pyramiding resistance genes can provide sufficient and consistent yield protection from soybean aphid in North America. [ABSTRACT FROM AUTHOR]

Background:STX2484 is a novel non-steroidal compound with potent anti-proliferative activity. These studies aimed to identify STX2484's mechanism of action, in vivo efficacy and activity in taxane-resistant breast cancer models.Methods:Effects of STX2484 and paclitaxel on proliferation, cell cycle and apoptosis were assessed in vitro in drug-resistant (MCF-7DOX) and non-resistant cells (MCF-7WT). STX2484 efficacy in βIII tubulin overexpression in MCF-7 cells was also determined. Anti-angiogenic activity was quantified in vitro by a co-culture model and in vivo using a Matrigel plug assay. An MDA-MB-231 xenograft model was used to determine STX2484 efficacy in vivo.Results:STX2484 is a tubulin disruptor, which induces p53 expression, Bcl2 phosphorylation, caspase-3 cleavage, cell cycle arrest and apoptosis. In addition, STX2484 is a potent anti-angiogenic agent in vitro and in vivo. In breast cancer xenografts, STX2484 (20 mg kg−1 p.o.) suppressed tumour growth by 84% after 35 days of daily dosing, with limited toxicity. In contrast to paclitaxel, STX2484 efficacy was unchanged in two clinically relevant drug-resistant models.Conclusions:STX2484 is an orally bioavailable microtubule-disrupting agent with in vivo anti-angiogenic activity and excellent in vivo efficacy with no apparent toxicity. Crucially, STX2484 has superior efficacy to paclitaxel in models of clinical drug resistance. [ABSTRACT FROM AUTHOR]

A numerical solution for the Radiation Transmission Efficiency (RTE) of electric and magnetic dipoles is obtained, and analysed with respect to frequency and spatial location. The results are compared against the findings of an equivalent analysis that used the closed-form expressions for the electromagnetic fields. It is shown that the two different methods present different findings with respect to the RTE of the dipoles. Conclusions are drawn as to the reason(s) behind the discrepancies between the two models, and provide the basis for future work. [ABSTRACT FROM AUTHOR]