51 research outputs found
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Network optimization for enhanced resilience of urban heat island measurements
The urban heat island is a well-known phenomenon that impacts a wide variety of city operations. With greater availability of cheap meteorological sensors, it is possible to measure the spatial patterns of urban atmospheric characteristics with greater resolution. To develop robust and resilient networks, recognizing sensors may malfunction, it is important to know when measurement points are providing additional information and also the minimum number of sensors needed to provide spatial information for particular applications. Here we consider the example of temperature data, and the urban heat island, through analysis of a network of sensors in the Tokyo metropolitan area (Extended METROS). The effect of reducing observation points from an existing meteorological measurement network is considered, using random sampling and sampling with clustering. The results indicated the sampling with hierarchical clustering can yield similar temperature patterns with up to a 30% reduction in measurement sites in Tokyo. The methods presented have broader utility in evaluating the robustness and resilience of existing urban temperature networks and in how networks can be enhanced by new mobile and open data sources
X-Irradiation at 0.5 Gy after the forced swim test reduces forced swimming-induced immobility in mice
The forced swim test (FST) is a screening model for antidepressant activity; it causes immobility and induces oxidative stress. We previously reported that radon inhalation has antidepressant-like effects in mice potentially through the activation of antioxidative functions upon radon inhalation. This study aimed to investigate the effect of prior and post low-dose X-irradiation (0.1, 0.5, 1.0 and 2.0 Gy) on FST-induced immobility and oxidative stress in the mouse brain, and the differences, if any, between the two. Mice received X-irradiation before or after the FST repeatedly for 5 days. In the post-FST-irradiated group, an additional FST was conducted 4h after the last irradiation. Consequently, animals receiving prior X-irradiation (0.1 Gy) had better mobility outcomes than sham-irradiated mice; however, their levels of lipid peroxide (LPO), an oxidative stress marker, remained unchanged. However, animals that received post-FST X-irradiation (0.5 Gy) had better mobility outcomes and their LPO levels were significantly lower than those of the sham-irradiated mice. The present results indicate that 0.5 Gy X-irradiation after FST inhibits FST-induced immobility and oxidative stress in mice
Comparison of CBF between pCASL and SPECT
Purpose: We compared the regional cerebral blood flow (rCBF) obtained by pulsed continuous arterial spin labeling (pCASL) and iodine-123-N-isopropyl-p-iodoamphetamine (IMP) single photon emission computed tomography (SPECT) using 3-dimensional stereotactic region-of-interest (ROI) software for automated definition of ROIs in anatomic regions of the brain.
Methods: Thirteen patients with cerebrovascular occlusive disease and three with transient ischemic attacks underwent pCASL and IMP SPECT imaging. We compared rCBF values of each anatomic region and calculated the correlation coefficients between pCASL and IMP SPECT. We also calculated the asymmetry index (AI) using ROIs in contralateral regions of the hemispheres.
Results: The rCBF values calculated from pCASL and IMP SPECT were comparable in most segments, but rCBF in the thalamus (P < 0.0001) and hippocampus (P = 0.0006) was significantly higher measured by pCASL than IMP SPECT. The correlation of rCBF between pCASL and IMP SPECT in the affected hemisphere (r = 0.50) tended to be lower than that in the normal hemisphere (r = 0.59), but not significantly different (P = 0.25). Moreover, there was a fixed bias for underestimation of rCBF by pCASL (P = 0.0047) in the affected hemisphere. The calculated AI showed a significant relationship between methods (r = 0.79, P < 0.0001).
Conclusion: The rCBF obtained by pCASL had positive relationships with IMP SPECT. However, it should be considered that pCASL tends to have a weak relationship with IMP SPECT in some normal regions and regions affected by cerebrovascular occlusive disease
Serial MRI Features of Canine GM1 Gangliosidosis: A Possible Imaging Biomarker for Diagnosis and Progression of the Disease
GM1 gangliosidosis is a fatal neurodegenerative lysosomal storage disease caused by an autosomal recessively inherited deficiency of β-galactosidase activity. Effective therapies need to be developed to treat the disease. In Shiba Inu dogs, one of the canine GM1 gangliosidosis models, neurological signs of the disease, including ataxia, start at approximately 5 months of age and progress until the terminal stage at 12 to 15 months of age. In the present study, serial MR images were taken of an affected dog from a model colony of GM1 gangliosidosis and 4 sporadic clinical cases demonstrating the same mutation in order to characterize the MRI features of this canine GM1 gangliosidosis. By 2 months of age at the latest and persisting until the terminal stage of the disease, the MR findings consistently displayed diffuse hyperintensity in the white matter of the entire cerebrum on T2-weighted images. In addition, brain atrophy manifested at 9 months of age and progressed thereafter. Although a definitive diagnosis depends on biochemical and genetic analyses, these MR characteristics could serve as a diagnostic marker in suspect animals with or without neurological signs. Furthermore, serial changes in MR images could be used as a biomarker to noninvasively monitor the efficacy of newly developed therapeutic strategies
Development of Skin Flaps for Reconstructive Surgery : Random Pattern Flap to Perforator Flap
Flap transplantation has been an important procedure in plastic and reconstructive surgery to cover and fill various defects. Flap necrosis due to blood circulation failure leads to severe complications, especially in a patient undergoing reconstruction concerning the body cavity after tumor ablation. Surgical procedures for flap transplantation have been further improved and developed. We have reviewed from the random pattern flap to the newest procedure, the perforator flap. Perforator vessels were investigated in the process of development of the fasciocutaneous flap and have become important for blood supply of the skin flap. Blood circulation of the flap has become more stable and reliable than ever with the development and findings of the perforator vessels. Further development of a skin flap will be based on the perforasome concept, which involves the study of the territory and linking of perforator vessels
Effect of antispasmodic drugs on endoscopic ultrasound/endoscopic ultrasound-guided fine-needle aspiration : A multicenter randomized controlled trial
Background and Objective: Antispasmodic drugs (ADs) have been used to reduce examination time or improve the quality of gastrointestinal endoscopy, although the practice is controversial. No evidence about the efficacy of AD for endoscopic ultrasonography/EUS-guided fine-needle aspiration (EUS/EUS-FNA) is available. This study was aimed to evaluate the efficacy of AD in EUS/EUS-FNA. Patients and Methods: A total of 400 patients with pancreaticobiliary, peripancreatic, or peribiliary disease or disorder undergoing EUS/EUS-FNA were prospectively and evenly randomized to undergo EUS/EUS-FNA with AD (w-AD) or without AD (w/o-AD). The primary endpoint was total EUS/EUS-FNA examination time. The secondary endpoints were visual analogue scale (VAS) scores of endoscopists (patient body motion, gastrointestinal peristalsis, and accomplishment of the purpose) and patients (pain, discomfort, and willingness to undergo re-examination), vital sign changes, adverse events, and sedative dose. Results: Two hundred patients in the w-AD group and 197 patients in the w/o-AD group were ultimately analyzed. The total examination time was similar between the groups (2299 ± 937 vs. 2259 ± 1019 s). The difference in total examination time from w/o-AD group to w-AD group was −40 s (95% confidence interval, −234-153 s), which was within the noninferiority margin. No statistical differences were observed in endoscopist and patient VAS scores, changes in vital signs, adverse events, or total sedative dose other than fentanyl between the groups. Conclusion: EUS/EUS-FNA can be effectively and safely performed w/o-AD. Further, randomized controlled trials on EUS/EUS-FNA in various disease entities may be required to confirm the results of this study (UMIN000008047)
Operator-bias-free Comparison of Quantitative Perfusion Maps Acquired with Pulsed-continuous Arterial Spin Labeling and Single-photon-emission Computed Tomography
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