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This is a copy of the slides presented at the meeting but not formally written up for the volume.
Complex oxides exhibit various physical properties such as ferromagnetism, dielectricity, and superconductivity. The nature of these physical properties is determined by very small characteristic length scales. Future heteroepitaxial devices based on such oxides have great potential for applications provided that the growth can be controlled on an atomic level.Currently, in-situ growth morphology characterization is mostly performed by diffraction techniques such as Reflection High Energy Electron Diffraction (RHEED). We have now realized a system, in which Atomic Force Microscopy (AFM) can be performed during Pulsed Laser Deposition (PLD). Deposition and force microscopy are performed in one vacuum chamber and via a fast transfer (in the order of seconds) the surface of a sample can be scanned. In our system we take advantage of the pulsed deposition process, because microscopy measurements can be carried out between the pulses. This provides real-time morphology information on the microscopic scale during growth. The transfer mechanism allows switching between microscopy and deposition with a re-position accuracy of ±500 nm which gives new opportunities to study growth processes. This system is especially useful to study crystal growth, phase transitions, diffusion processes and nanoparticle formation. Furthermore, it will provide information if RHEED is not possible, for example during amorphous and polycrystalline growth. In this contribution, we will present the results obtained with a few model systems on oxide surfaces. We have used treated SrTiO3 (001) oxide substrates with 0.4 nm high substrate steps which are ideal for these experiments. Several materials are currently investigated, such as Au, SrRuO3, PbTiO3 and transparent conducting indium tin oxide. The in-situ AFM has been used to study the initial growth of these materials at various deposition conditions. The physical properties of these materials are correlated with the growth conditions, such as deposition pressure, fluency and substrate temperature. Besides showing the growth results obtained with the AFM, the latest equipment developments will be presented. To scan at elevated temperatures, small heaters have been developed. These small thermal mass heaters are designed in such a way to obtain stable monitoring settings at temperatures >973K in a high pressure environment or even ambient pressure. With high temperature microscopy, growth characterization at typical deposition conditions of complex oxides becomes feasible.
Hydrilla is an invasive aquatic plant that has rapidly spread through many inland water bodies across the globe by outcompeting native aquatic plants. The negative impacts of hydrilla invasion have become a concern for water resource management authorities, power companies, and environmental scientists. The early detection of hydrilla infestation is very important to reduce the costs associated with control and removal efforts of this invasive species. Therefore, in this study, we aimed to develop a tool for rapid, frequent, and large-scale monitoring and predicting spatial extent of hydrilla habitat. This was achieved by integrating in situ and Landsat 8 Operational Land Imager satellite data for Lake J. Strom Thurmond, the largest US Army Corps of Engineers lake east of the Mississippi River, located on the border of Georgia and South Carolina border. The predictive model for presence of hydrilla incorporated radiometric and physical measurements, including remote-sensing reflectance, Secchi disk depth (SDD), light-attenuation coefficient (Kd), maximum depth of colonization (Zc), and percentage of light available through the water column (PLW). The model-predicted ideal habitat for hydrilla featured high SDD, Zc, and PLW values, low values of Kd. Monthly analyses based on satellite images showed that hydrilla starts growing in April, reaches peak coverage around October, begins retreating in the following months, and disappears in February. Analysis of physical and meteorological factors (i.e., water temperature, surface runoff, net inflow, precipitation) revealed that these parameters are closely associated with hydrilla extent. Management agencies can use these results not only to plan removal efforts but also to evaluate and adapt their current mitigation efforts.
Children with tetralogy of Fallot, pulmonary atresia, and major aortopulmonary collaterals (TOF/MAPCAs) are at risk for post-operative respiratory complications after undergoing unifocalisation surgery. Thus, we assessed and further defined the incidence of airway abnormalities in our series of over 500 children with TOF/MAPCAs as determined by direct laryngoscopy, chest computed tomography (CT), and/or bronchoscopy.
The medical records of all patients with TOF/MAPCAs who underwent unifocalisation or pulmonary artery reconstruction surgery from March, 2002 to June, 2018 were reviewed. Anaesthesia records, peri-operative bronchoscopy, and/or chest CT reports were reviewed to assess for diagnoses of abnormal or difficult airway. Associations between chromosomal anomalies and airway abnormalities – difficult anaesthetic airway, bronchoscopy, and/or CT findings – were defined.
Of the 564 patients with TOF/MAPCAs who underwent unifocalisation or pulmonary artery reconstruction surgery at our institution, 211 (37%) had a documented chromosome 22q11 microdeletion and 28 (5%) had a difficult airway/intubation reported at the time of surgery. Chest CT and/or peri-operative bronchoscopy were performed in 234 (41%) of these patients. Abnormalities related to malacia or compression were common. In total 35 patients had both CT and bronchoscopy within 3 months of each other, with concordant findings in 32 (91%) and partially concordant findings in the other 3.
This is the largest series of detailed airway findings (direct laryngoscopy, CT, and bronchoscopy) in TOF/MAPCAS patients. Although these findings are specific to an at-risk population for airway abnormalities, they support the utility of CT and /or bronchoscopy in detecting airway abnormalities in patients with TOF/MAPCAs.
Despite established clinical associations among major depression (MD), alcohol dependence (AD), and alcohol consumption (AC), the nature of the causal relationship between them is not completely understood. We leveraged genome-wide data from the Psychiatric Genomics Consortium (PGC) and UK Biobank to test for the presence of shared genetic mechanisms and causal relationships among MD, AD, and AC.
Linkage disequilibrium score regression and Mendelian randomization (MR) were performed using genome-wide data from the PGC (MD: 135 458 cases and 344 901 controls; AD: 10 206 cases and 28 480 controls) and UK Biobank (AC-frequency: 438 308 individuals; AC-quantity: 307 098 individuals).
Positive genetic correlation was observed between MD and AD (rgMD−AD = + 0.47, P = 6.6 × 10−10). AC-quantity showed positive genetic correlation with both AD (rgAD−AC quantity = + 0.75, P = 1.8 × 10−14) and MD (rgMD−AC quantity = + 0.14, P = 2.9 × 10−7), while there was negative correlation of AC-frequency with MD (rgMD−AC frequency = −0.17, P = 1.5 × 10−10) and a non-significant result with AD. MR analyses confirmed the presence of pleiotropy among these four traits. However, the MD-AD results reflect a mediated-pleiotropy mechanism (i.e. causal relationship) with an effect of MD on AD (beta = 0.28, P = 1.29 × 10−6). There was no evidence for reverse causation.
This study supports a causal role for genetic liability of MD on AD based on genetic datasets including thousands of individuals. Understanding mechanisms underlying MD-AD comorbidity addresses important public health concerns and has the potential to facilitate prevention and intervention efforts.
In X-ray fluorescence analysis, the specific secondary radiation intensities of the elements are generated and measured by a spectrometer. Usually, the measured intensities are corrected for instrument drift first, then converted into element concentrations. In routine analysis, the intensity is always affected by the instability of the instrument. Instrumental instability consists of two components: short and long term drift Short-term instability is caused by fluctuations in the ambient laboratory conditions and the instrument's components. Long-term drift is caused by aging of the instrument's components (mainly X-ray tube, crystals, detectors, electronic circuitry) and results in a gradual intensity decrease. For example, the X-ray tube output decreases due to pitting of the target and sublimation of metal on the inside of the window. The quantum efficiency of detectors gradually decreases due to drift in potential supply and changes in ambient pressure and temperature.
One of the most important properties that characterizes alumina is its elemental composition. Although XRF has been applied to the analysis of aluminas for the past three decades, special aluminas have always presented a maj or challenge. Moreover, only recently did it become possible to analyze for light elements such as Na. Two new sample preparation techniques for elemental analysis of aluminas by XRF were developed. One is based on briquetted powders, another involves fused samples. Their advantages and limitations will be presented. In the case of fusion one analytical program was applied to aII types of aluminas, The performance of each method will be discussed.
The Powder Diffraction File (PDF), published by the JCPDS-International Centre for Diffraction Data, is one of the most widely used scientific data bases. It currently consists of about 40,000 x-ray diffraction patterns, organized into 32 sets and 5 subfiles: metals and alloys, minerals, common phases, forensic patterns, and those from the National Bureau of Standards (NBS), New patterns are being added to the PDF at a rate of 2,000 patterns per year. The sources of these patterns are the literature, private contributions, grants in-aid projects, and the JCPDS Associateship at the NBS.
Gold wires were vaporized by the exploding-wire phenomenon using a 20 μF capacitor bank charged to voltages up to 14 kV. The resulting condensate, an aerosol or metallic smoke, was collected on membrane filters and subjected to X-ray analysis to determine lattice constant, crystallite size, and behavior with isothermal annealing. Wire explosions were conducted in au ambient atmosphere of ait or nitrogen at barometric pressure. It is estimated that the quench rate for this material is of the order of 108 deg/sec from the melting point although no substrate is involved and it is expected that any effects of epitaxial origin on the structure would be minimized.
Before annealing, diffractograms showed broad peaks apparently shifted to the high-angle side. Line breadth may be attributed primarily to particle size broadening, since ft correlates well with size determined by electron microscopy, (β cos θ) is linear with θ, and [(β cos θ)/λ] is approximately constant for three radiations used. Crystallite size is of the order of 400 Å and is observed to decrease roughly with increasing voltage used for vaporization. The observed lattice decrement, approximately 0.2%, generally increases with voltage used for vaporization, and apparently correlates rather well with the inverse of sise as has been reported in some work on thin gold films. However, studies of colloidal gold particles do not show significant lattice shifts, although the particle size is less than 100 Å so that the decrements observed may be due to factors other than size alone. For this black, particulate material, some lattice decrement apparently persists even after protracted isothermal annealing below the melting point. Crystallite size increases with annealing but remains below about 1000 Å. Results suggest that the lattice decrements observed in condensed gold vapor are due to surface tension effects and the presence of vacancy aggregates.
X-ray fluorescence analysis has been used in the aluminum industry since the beginning of the 1950's. Initial applications involved predominantly raw materials such as bauxite. During the last decades its use expanded to every stage of aluminum production and today, XRF analysis is a recognized analyticaI technique, applied routinely in exploration, reduction and fabrication processes. Typical XRF applications in the aluminum industry at present are listed in Table 1. The number of determinations given represents usual industrial requirements, and may vary between laboratories. The sample preparation techniques are again the most commonly used for the applications.
Watermelon [Citrullus lanatus (Thunb.) Matsum & Nakai] grafting is commonly used for management of diseases caused by soilborne pathogens; however, little research exists describing the effect of grafting on the weed-competitive ability of watermelon. Field experiments determined the response in yield, fruit number, and fruit quality of grafted and nongrafted watermelon exposed to increasing densities of Palmer amaranth (Amaranthus palmeri S. Watson). Grafting treatments included ‘Exclamation’ triploid (seedless) watermelon grafted on two interspecific hybrid squash rootstocks ‘Carnivor’ and ‘Kazako’, with nongrafted Exclamation as the control. Weed treatments included A. palmeri at densities of 1, 2, 3, and 4 A. palmeri plants per watermelon planting hole (0.76-m row) and a weed-free control. Increasing A. palmeri densities caused significant reductions (P <0.05) in marketable watermelon yield and marketable fruit number. Watermelon yield reduction was described by a rectangular hyperbola model, and 4 A. palmeri plants planting hole−1 reduced marketable yield 41%, 38%, and 65% for Exclamation, Carnivor, and Kazako, respectively. Neither grafting treatment nor A. palmeri density had a biologically meaningful effect on soluble solids content or on the incidence of hollow heart in watermelon fruit. Amaranthus palmeri seed and biomass production was similar across weed population densities, but seed number per female A. palmeri decreased according to a two-parameter exponential decay equation. Thus, increasing weed population densities resulted in increased intraspecific competition among A. palmeri plants. While grafting may offer benefits for disease resistance, no benefits regarding weed-competitive ability were observed, and a consistent yield penalty was associated with grafting, even in weed-free treatments.
Despite the lack of another Flagship-class mission such as Cassini–Huygens, prospects for the future exploration of Saturn are nevertheless encouraging. Both NASA and the European Space Agency (ESA) are exploring the possibilities of focused interplanetary missions (1) to drop one or more in situ atmospheric entry probes into Saturn and (2) to explore the satellites Titan and Enceladus, which would provide opportunities for both in situ investigations of Saturn’s magnetosphere and detailed remote-sensing observations of Saturn’s atmosphere. Additionally, a new generation of powerful Earth-based and near-Earth telescopes with advanced instrumentation spanning the ultraviolet to the far-infrared promise to provide systematic observations of Saturn’s seasonally changing composition and thermal structure, cloud structures and wind fields. Finally, new advances in amateur telescopic observations brought on largely by the availability of low-cost, powerful computers, low-noise, large-format cameras, and attendant sophisticated software promise to provide regular, longterm observations of Saturn in remarkable detail.
Field experiments determined the critical period for weed control (CPWC) in grafted and nongrafted watermelon [Citrullus lanatus (Thumb.) Matsum. & Nakai] grown in plasticulture. Transplant types included ‘Exclamation’ seedless watermelon as the nongrafted control as well as Exclamation grafted onto two interspecific hybrid squash (ISH) rootstocks, ‘Carnivor’ and ‘Kazako’. To simulate weed emergence throughout the season, establishment treatments (EST) consisted of two seedlings each of common purslane (Portulaca oleracea L.), large crabgrass [Digitaria sanguinalis (L.) Scop.], and yellow nutsedge (Cyperus esculentus L.) transplanted in a 15 by 15 cm square centered on watermelon plants at 0, 2, 3, 4, and 6 wk after watermelon transplanting (WATr) and remained until the final watermelon harvest at 11 WATr. To simulate weed control at different times in the season, removal treatments (REM) consisted of two seedlings of the same weed species transplanted in a 15 by 15 cm square centered on watermelon plants on the same day of watermelon transplanting and allowed to remain until 2, 3, 4, 6, and 11 WATr, at which time they were removed. Season-long weedy and weed-free controls were included for both EST and REM studies in both years. For all transplant types, aboveground biomass of weeds decreased as weed establishment was delayed and increased as weed removal was delayed. The predicted CPWC for nongrafted Exclamation and Carnivor required only a single weed removal between 2.3 and 2.5 WATr and 1.9 and 2.6 WATr, respectively, while predicted CPWC for Kazako rootstock occurred from 0.3 to 2.6 WATr. Our study results suggest that weed control for this mixed population of weeds would be similar between nongrafted Exclamation and Exclamation grafted onto Carnivor. But the observed CPWC of Exclamation grafted onto Kazako suggests that CPWC may vary with specific rootstock–scion combinations.
Experts have raised concerns that oxytocin for labor induction and augmentation may have detrimental effects on the neurodevelopment of children. To investigate whether there is the reason for concern, we reviewed and evaluated the available evidence by searching databases with no language or date restrictions up to 9 September 2018. We included English-language studies reporting results on the association between perinatal oxytocin exposure and any cognitive impairment, psychiatric symptoms or disorders in childhood. We assessed the quality of studies using the Newcastle–Ottawa Quality Assessment Scales. Independent risk estimates were pooled using random-effects meta-analyses when at least two independent datasets provided data on the same symptom or disorder. Otherwise, we provided narrative summaries. Two studies examined cognitive impairment, one examined problem behavior, three examined attention-deficit/hyperactivity disorder (ADHD) and seven focused on autism spectrum disorders (ASD). We provided narrative summaries of the studies on cognitive impairment. For ADHD, the pooled risk estimate was 1.17; 95% confidence interval (CI) 0.77–1.78, based on a pooled sample size of 5 47 278 offspring. For ASD, the pooled risk estimate was 1.10; 95% CI 1.04–1.17, based on 8 87 470 offspring. Conclusions that perinatal oxytocin increases the risks of neurodevelopmental problems are premature. Observational studies of low to high quality comprise the evidence-base, and confounding, especially by the genetic or environmental vulnerability, remains an issue. Current evidence is insufficient to justify modifying obstetric guidelines for the use of oxytocin, which state that it should only be used when clinically indicated.
Internal gravity wave energy contributes significantly to the energy budget of the oceans, affecting mixing and the thermohaline circulation. Hence it is important to determine the internal wave energy flux
is the pressure perturbation field and
is the velocity perturbation field. However, the pressure perturbation field is not directly accessible in laboratory or field observations. Previously, a Green’s function based method was developed to calculate the instantaneous energy flux field from a measured density perturbation field
, given a constant buoyancy frequency
. Here we present methods for computing the instantaneous energy flux
for an internal wave field with vertically varying background
, as in the oceans where
typically decreases by two orders of magnitude from the pycnocline to the deep ocean. Analytic methods are presented for computing
from a density perturbation field for
varying linearly with
. To generalize this approach to arbitrary
, we present a computational method for obtaining
. The results for
for the different cases agree well with results from direct numerical simulations of the Navier–Stokes equations. Our computational method can be applied to any density perturbation data using the MATLAB graphical user interface ‘EnergyFlux’.
Patients with tetralogy of Fallot, pulmonary atresia, and major aortopulmonary collaterals are at risk for prolonged hospitalisation after unifocalisation. Feeding problems after congenital heart surgery are associated with longer hospital stay. We sought to determine the impact of baseline, intra-operative, and postoperative factors on the need for feeding tube use at the time of discharge.
We included patients with the aforementioned diagnosis undergoing unifocalisation from ages 3 months to 4 years from 2010 to 2016. We excluded patients with a pre-existing feeding tube. Patients discharged with an enteric tube were included in the feeding tube group. We compared the feeding tube group with the non-feeding-tube group by univariable and multi-variable logistic regression.
Of the 56 patients studied, 41% used tube feeding. Median age and weight z-score were similar in the two groups. A chromosome 22q11 deletion was associated with the need for a feeding tube (22q11 deletion in 39% versus 15%, p=0.05). Median cardiopulmonary bypass time in the feeding tube group was longer (335 versus 244 minutes, p=0.04). Prolonged duration of mechanical ventilation was associated with feeding tube use (48 versus 3%, p=0.001). On multi-variable analysis, prolonged mechanical ventilation was associated with feeding tube use (odds ratio 10.2, 95% confidence intervals 1.6; 63.8).
Among patients with tetralogy of Fallot, pulmonary atresia, and major aortopulmonary collaterals who were feeding by mouth before surgery, prolonged mechanical ventilation after unifocalisation surgery was associated with feeding tube use at discharge. Anticipation of feeding problems in this population and earlier feeding tube placement may reduce hospital length of stay.
This study employs a two-way fixed effects research design to measure the mortality impact and cost-effectiveness of cancer drugs: It analyzes the correlation across 36 countries between the relative mortality from 19 types of cancer in 2015 and the relative number of drugs previously launched in that country to treat that type of cancer, controlling for relative incidence. The sample size (both in terms of number of observations and population covered) of this study is considerably larger than the sample sizes of previous studies; a new and improved method of analyzing the lag structure of the relationship between drug launches and life-years lost is used; and a larger set of measures of the burden of cancer is analyzed. The number of DALYs and life-years lost are unrelated to drug launches 0–4 years earlier. This is not surprising, since utilization of a drug tends to be quite low during the first few post-launch years. Moreover, there is likely to be a lag of several years between utilization of a drug and its impact on mortality. However, mortality is significantly inversely related to the number of drug launches at least 5 years earlier, especially to drug launches 5–9 years earlier. One additional drug for a cancer site launched during 2006–2010 is estimated to have reduced the number of 2015 DALYs due to cancer at that site by 5.8%;; one additional drug launched during 1982–2005 is estimated to have reduced the number of 2015 DALYs by about 2.6%. Lower quality (or effectiveness) of earlier vintage drugs may account for their smaller estimated effect. We estimate that drugs launched during the entire 1982–2010 period reduced the number of cancer DALYs in 2015 by about 23.0%, and that, in the absence of new drug launches during 1982–2010, there would have been 26.3 million additional DALYs in 2015. Also, the nine countries with the largest number of drug launches during 1982–2010 are estimated to have had 14% fewer cancer DALYs (controlling for incidence) in 2015 than the nine countries with the smallest number of drug launches during 1982–2010. Estimates of the cost per life-year gained in 2015 from drugs launched during 2006–2010 range between $1,635 (life-years gained at all ages) and $2,820 (life-years gained before age 65). These estimates are similar to those obtained in previous country-specific studies of Belgium, Canada, and Mexico, and are well below the estimate obtained in one study of Switzerland. Mortality in 2015 is strongly inversely related to the number of drug launches in 2006–2010. If the relationship between mortality in 2020 and the number of drug launches in 2011–2015 is similar, drug launches 5–9 years earlier will reduce mortality even more (by 9.9%) between 2015 and 2020 than they did (by 8.4%) between 2010 and 2015.