22 research outputs found

    Pheochromocytoma multisystem crisis treated with emergency surgery: a case report and literature review

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    Background: Pheochromocytoma is a neuroendocrine tumor that predominantly presents with hypertension, palpitations, and tachycardia due to excessive catecholamine excretion. Although pheochromocytoma multisystem crisis (PMC) is relatively rare, urologists and clinicians should focus on early diagnosis as delay in initiating the appropriate treatment can lead to mortality Case presentation: A 70-year-old man developed ileus after a few days of medication for hypertension. Computed tomography incidentally revealed a left adrenal mass. This finding together with his clinical course was compatible with pheochromocytoma. An Ī±-blocker was administered immediately, and his blood pressure was well controlled. However, his general condition and laboratory data deteriorated rapidly, and the patient was diagnosed with PMC with lethal status. Thus, emergency adrenalectomy was performed without confirmation of catecholamine levels. From the resected specimen, his tumor was judged as pheochromocytoma. On immunohistochemical analysis, the proliferation index evaluated by Ki-67 staining was 9.7 %. This case report was approved by the Human Ethics Review Committee of the Nagasaki University Hospital. Conclusion: The present case of PMC was successfully treated with emergency surgery. The benign pheochromocytoma also presented with high cell proliferation potential, which may be a cause of the extreme aggressiveness of PMC

    Localized Delay Signals Detected by Synthetic Aperture Radar Interferometry and Their Simulation by WRF 4DVAR

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    Localized propagation delay signals associated with linealigned convective cells were detected by the Synthetic Aperture Radar Interferometry (InSAR) technique on 25 August 2010 in Niigata prefecture. The maximum amplitude of the signal reached up to 22.5 cm, which was approximately equivalent to 29 mm anomaly in precipitable water vapor (PWV). The nationwide radar rainfall intensity captured the spatial distribution of hydrometeors on both land and sea, which was similar to that of the InSAR-derived water vapor field, suggesting that the convective cells were initiated on the Japan Sea to the west-southwest of the observation area. A numerical weather model (NWM) simulation with the grid spacing of 2.5 km reproduced line-aligned convective cells with 3 cm smaller maximum amplitude to that in InSAR. A NWM simulation that assimilates Global Navigation Satellite System (GNSS)-derived PWV data for four-dimensional variational assimilation enhanced the water vapor flux convergence at the surface, which improved the amplitude of the localized delay signals. The advantage of the unique water vapor observation by InSAR enabled us to assess the meso-gamma scale NWM reproducibility in terms of water vapor, which is one of the fundamental prognostic parameter for NWMs

    Are numerical weather model outputs helpful to reduce tropospheric delay signals in InSAR data?

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    Interferometric Synthetic Aperture Radar (InSAR) phase data include not only signals due to crustal movements but also those associated with microwave propagation delay through the atmosphere. In particular, the effect of water vapor can generate apparent signals on the order of a few centimeters or more, and prevent us from detecting such geophysical signals as those due to secular crustal deformation. In order to examine if and to what extent numerical weather model (NWM) outputs are helpful to reduce the tropospheric delay signals at spatial scales of 5ļ½ž50 km wavelengths, we compared three approaches of tropospheric signal reduction, using 54 interferograms in central Hokkaido, Japan. The first approach is the conventional topography-correlated delay correction that is based on the regional digital elevation model (DEM). The second approach is based on the Japan Meteorological Agency's operational meso-scale analysis model (MSM) data, where we compute tropospheric delays and subtract them from the interferogram. However, the MSM data are available at predefined epochs, and their spatial resolution is about 10 km, and therefore we need to interpolate both temporally and spatially to match with interferograms. Expecting to obtain a more physically plausible reduction of the tropospheric effects, we ran a 1-km mesh high-resolution numerical weather model WRF (Weather Research and Forecasting model) by ourselves, using the MSM data as the initial and boundary conditions. The third approach is similar to the second approach except that we make use of the WRF-based tropospheric data. Results show that if the topography-correlated phases are significant, both the conventional DEM-based approach and the MSM-based approach reveal comparable performances. However, when the topography-correlated phases are insignificant, none of the approaches could efficiently reduce the tropospheric phases. Although it could reduce the tropospheric signals in a local area, in none of the case studies did the WRF model produce the "best" performance. Whereas the global atmospheric model outputs are shown to be effective in reducing long-wavelength tropospheric signals, we consider that further improvements are needed for the initial and boundary condition data for high-resolution NWM, so that the NWM-based approach will become more reliable even in the case of a non-stratified troposphere

    Detections and simulations of tropospheric water vapor fluctuations due to trapped lee waves by ALOS-2/PALSAR-2 ScanSAR interferometry

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    Abstract Detailed wave-like spatial patterns of atmospheric propagation delay signals associated with mountain lee waves were detected in Hokkaido and Tohoku by synthetic aperture radar (SAR) interferometry (InSAR) with the ScanSAR mode observation data of a Phased Array-type L-band Synthetic Aperture Radar 2 on board the Advanced Land Observing Satellite 2. Both cases occurred under stable atmosphere conditions. The InSAR-observed peak-to-trough line of sight changes in the mountain wave signals was 4 and 5Ā cm with the horizontal wavelengths of 9 and 15Ā km in Hokkaido and Tohoku, respectively. Locations of positive phase maxima in the mountain wave signals coincides with locations of cloud streets observed by visible satellite imagery, indicating that crests of mountain waves contain relatively much water vapor compared with wave troughs. Numerical weather simulations with the horizontal grid spacing of 1Ā km were performed to reproduce InSAR phase variations, and as a result those simulations could reasonably reproduce observed wave amplitudes and wavelengths in both cases. On the other hand, numerical simulations tended to overestimate wave attenuation rates: simulated mountain waves decreased as the wave propagated faster than those of observed signals. Because the simulated wave attenuation rate is sensitive to physics in the planetary boundary layer (PBL), we investigated the reproducibility of five PBL schemes implemented in the WRF model. As a result, all the PBL schemes showed little attenuation except for the Yonsei University scheme (YSU), while the wavelength in the YSU was most close to the observation. Our study demonstrated the uniqueness and usefulness of InSAR for meteorological application as the ability to map the detailed water vapor distribution regardless of cloud cover. In addition, the reasonable reproducibility of the water vapor delay signal due to lee waves by the numerical weather model encourages researchers who tackle the correction of the tropospheric propagation delay, increasing the accuracy in detecting surface deformations. Graphical abstract

    Quantifying the effect of autonomous adaptation to global river flood projections: application to future flood risk assessments

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    This study represents the first attempt to quantify the effects of autonomous adaptation on the projection of global flood hazards and to assess future flood risk by including this effect. A vulnerability scenario, which varies according to the autonomous adaptation effect for conventional disaster mitigation efforts, was developed based on historical vulnerability values derived from flood damage records and a river inundation simulation. Coupled with general circulation model outputs and future socioeconomic scenarios, potential future flood fatalities and economic loss were estimated. By including the effect of autonomous adaptation, our multimodel ensemble estimates projected a 2.0% decrease in potential flood fatalities and an 821% increase in potential economic losses by 2100 under the highest emission scenario together with a large population increase. Vulnerability changes reduced potential flood consequences by 64%ā€“72% in terms of potential fatalities and 28%ā€“42% in terms of potential economic losses by 2100. Although socioeconomic changes made the greatest contribution to the potential increased consequences of future floods, about a half of the increase of potential economic losses was mitigated by autonomous adaptation. There is a clear and positive relationship between the global temperature increase from the pre-industrial level and the estimated mean potential flood economic loss, while there is a negative relationship with potential fatalities due to the autonomous adaptation effect. A bootstrapping analysis suggests a significant increase in potential flood fatalities (+5.7%) without any adaptation if the temperature increases by 1.5ā€‰Ā°Cā€“2.0ā€‰Ā°C, whereas the increase in potential economic loss (+0.9%) was not significant. Our method enables the effects of autonomous adaptation and additional adaptation efforts on climate-induced hazards to be distinguished, which would be essential for the accurate estimation of the cost of adaptation to climate change

    Synthesis, Structure, and Optical and Redox Properties of Chlorophyll Derivatives Directly Coordinating Ruthenium Bisbipyridine at the Peripheral Ī²ā€‘Diketonate Moiety

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    The diketonate group of the peripheral position in chlorophyll derivatives <b>1</b> and <b>2</b> coordinated ruthenium bisbipyridine to give direct linkages <b>3</b>ā€“<b>5</b> of the chlorin ring with the RuĀ­(II) complex. Zinc metalation of the central position in the chlorin ring of free base <b>3</b> afforded the Ruā€“Zn binuclear complex <b>3-Zn</b>. Because the diketonate group at the C3 position of chlorophyll derivatives coordinated to bulky RuĀ­(bpy)<sub>2</sub><sup>2+</sup>, the plane of the diketonate group was twisted from the chlorin Ļ€ ring in synthetic <b>3</b>ā€“<b>5</b> and <b>3-Zn</b> to lead to a partial deconjugation and a slight blue shift of the longest wavelength electronic absorption band in dichloromethane. A broad metal-to-ligand charge-transfer absorption band derived from the Ru complex was observed around 500 nm, in addition to visible absorption bands from the chlorophyll moiety. Chlorophyll derivatives <b>3</b>ā€“<b>5</b> and <b>3-Zn</b> directly coordinating the ruthenium complex were less fluorescent in dichloromethane than chlorophyllā€“diketonate ligands <b>1</b>, <b>2</b>, and <b>1-Zn</b> due to the heavy atom effect of the ruthenium in a molecule. The coordination to the ruthenium complex moiety at the peripheral position shifted the electrochemical reduction of the chlorin part in acetonitrile to a negative potential, and the coordination to zinc at the central position decreased the redox potentials. Chemical modification of the bipyridine and diketonate ligands of the ruthenium complexes greatly affected the redox potentials of RuĀ­(II)/(III) and/or RuĀ­(II)/(I) but minimally the redox properties of the chlorin moiety. Substitution with electron-donating groups shifted the former to a negative potential but only barely shifted the latter. The zinc metalation caused no apparent shifts for the redox potentials of the Ru center
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