Investigation of multi-mode spin-phonon coupling and local B-site disorder in Pr2CoFeO6 by Raman spectroscopy and correlation with its electronic structure by XPS and XAS studies

Electronic structure of Pr₂CoFeO₆ (at 300 K) was investigated by x-ray photoemission spectroscopy (XPS) and x-ray absorption spectroscopy techniques. All three cations, i.e. Pr, Co and Fe were found to be trivalent in nature. XPS valance band analysis suggested the system to be insulating in nature. The analysis suggested that Co³⁺ ions exist in low spin state in the system. Moreover, Raman spectroscopy study indicated the random distribution of the B-site ions (Co/Fe) triggered by same charge states. In temperature-dependent Raman study, the relative heights of the two observed phonon modes exhibited anomalous behaviour near magnetic transition temperature T _N ~ 270 K, thus indicating towards interplay between spin and phonon degrees of freedom in the system. Furthermore, clear anomalous softening was observed below T _N which confirmed the existence of strong spin-phonon coupling occurring for at least two phonon modes of the system. The line width analysis of the phonon modes essentially ruled out the role of magnetostriction effect in the observed phonon anomaly. The investigation of the lattice parameter variation across T _N (obtained from the temperature-dependent neutron diffraction measurements) further confirmed the existence of the spin-phonon coupling.

Recurrent Congenital Heart Diseases Among Neonates Born to Mothers with Congenital Heart Diseases

The frequency of newborns with congenital heart disease (CHD) is approximately 1% in the general population; however, the recurrence rate of CHD in mothers with CHD differs in ethnicity and reports. We therefore aimed to determine the prevalence of CHD among neonates born to mothers with CHD in our institute in Japan. We reviewed the medical charts of 803 neonates delivered by 529 women with CHD at the National Cerebral and Cardiovascular Center from 1982 to 2016. They included isolated ventricular septal defect (VSD,31.4%), isolated atrial septal defect (ASD, 23.3%), tetralogy of Fallot (TOF,10.6%). We defined CHD in neonates as being diagnosed within 1 month of birth. We estimated that the average rate of the CHD recurrence was 3.1%. The recurrence ratios in each maternal CHD were 8.6%, 7.1%, 6.2%, 4.8%, 3.6%, and 1.5% for PS, CoA, TOF, atrioventricular septal defect, VSD, and ASD, respectively. The rate of CHD in offsprings whose mothers have CHD was 3 times greater than that of mothers with healthy hearts. Almost half of neonates with CHD had the same phenotype as their mother in our series. Especially, PS and CoA were closely related to the type of maternal CHD.

Deep mapping gentrification in a large Canadian city using deep learning and Google Street View

Gentrification is multidimensional and complex, but there is general agreement that visible changes to neighbourhoods are a clear manifestation of the process. Recent advances in computer vision and deep learning provide a unique opportunity to support automated mapping or ‘deep mapping’ of perceptual environmental attributes. We present a Siamese convolutional neural network (SCNN) that automatically detects gentrification-like visual changes in temporal sequences of Google Street View (GSV) images. Our SCNN achieves 95.6% test accuracy and is subsequently applied to GSV sequences at 86110 individual properties over a 9-year period in Ottawa, Canada. We use Kernel Density Estimation (KDE) to produce maps that illustrate where the spatial concentration of visual property improvements was highest within the study area at different times from 2007–2016. We find strong concordance between the mapped SCNN results and the spatial distribution of building permits in the City of Ottawa from 2011 to 2016. Our mapped results confirm those urban areas that are known to be undergoing gentrification as well as revealing areas undergoing gentrification that were previously unknown. Our approach differs from previous works because we examine the atomic unit of gentrification, namely, the individual property, for visual property improvements over time and we rely on KDE to describe regions of high spatial intensity that are indicative of gentrification processes.

Utility of Fluid Assessment Based on the Intrathoracic Impedance Monitoring in a Peripartum Woman with Heart Disease

Recently, implantable cardioverter-defibrillators (ICD) have become capable of monitoring intrathoracic impedance to detect an increased fluid volume and heart failure. Pregnancy is a well-known cause of an increased body fluid volume; however, it is not clear whether the measurement of intrathoracic impedance by ICD is clinically useful for precisely detecting heart failure in pregnant women. We herein report the case of a 39-year-old woman with an ICD that had been implanted after an event of ventricular fibrillation due to severe aortic regurgitation with a bicuspid aortic valve. Elevated right ventricular pressure and brain natriuretic peptide levels were detected at 37 weeks of gestation and postpartum. At the same time, the ICD's stored fluid index gradually increased and exceeded the threshold on the 10th day after delivery. She was treated with diuretics and recovered from postpartum heart failure. The physiological volume changed in the perinatal period, but we were still able to detect heart failure by ICD. Intrathoracic impedance monitoring is effective in the perinatal field.

Changes in echocardiographic parameters and hypertensive disorders in pregnancies of women with aortic coarctation

OBJECTIVES

Pregnancy can be well tolerated after the repair of aortic coarctation. However, a higher incidence of hypertensive disorders during these pregnancies was reported. We analyzed the perinatal changes in echocardiographic parameters in women with aortic coarctation and investigated the risk factors of gestational hypertension (GH).

METHODS

We retrospectively identified 15 pregnancies in nine Japanese women with aortic coarctation between 1982 and 2015. We categorized the patients according to the presence/absence of GH as the group with GH(n=3) and that without GH(n=12). The echocardiographic parameters were compared between groups.

RESULTS

Our analysis revealed that a pre-pregnancy Doppler-measured pressure gradient≥20mmHg and a left ventricular mass index≥95g/m² were significant risk factors for GH. The left ventricular end-diastolic diameters at the first and the third trimesters, the left ventricular end-systolic diameters at the first trimester, and the left ventricular ejection fraction at the third trimester were also significantly higher in the pregnancies with GH. All of these findings had been obtained before the patients' GH occurred.

CONCLUSIONS

Hypertrophy of the left ventricle with a lower ejection fraction and a high pressure gradient across the coarctation were risk factors for GH in the patients with aortic coarctation. Thus, serial measurements using echocardiography are important for predicting GH in women with aortic coarctation. However, further research investigating this finding with a larger sample size is needed.

A direct observation method for auditing large urban centers using stratified sampling, mobile GIS technology and virtual environments

BACKGROUND

With the expansion and growth of research on neighbourhood characteristics, there is an increased need for direct observational field audits. Herein, we introduce a novel direct observational audit method and systematic social observation instrument (SSOI) for efficiently assessing neighbourhood aesthetics over large urban areas.

METHODS

Our audit method uses spatial random sampling stratified by residential zoning and incorporates both mobile geographic information systems technology and virtual environments. The reliability of our method was tested in two ways: first, in 15 Ottawa neighbourhoods, we compared results at audited locations over two subsequent years, and second; we audited every residential block (167 blocks) in one neighbourhood and compared the distribution of SSOI aesthetics index scores with results from the randomly audited locations. Finally, we present interrater reliability and consistency results on all observed items.

RESULTS

The observed neighbourhood average aesthetics index score estimated from four or five stratified random audit locations is sufficient to characterize the average neighbourhood aesthetics. The SSOI was internally consistent and demonstrated good to excellent interrater reliability. At the neighbourhood level, aesthetics is positively related to SES and physical activity and negatively correlated with BMI.

CONCLUSION

The proposed approach to direct neighbourhood auditing performs sufficiently and has the advantage of financial and temporal efficiency when auditing a large city.