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Brown adipose tissue (BAT), which produces energy and is known to play a role as a hibernating gland, is sometimes visualized on F-FDG PET in children or in slender young adults in a cold environment. Because BAT is activated by catecholamines, FDG uptake in BAT is also observed in patients with pheochromocytoma or paraganglioma. We present the case of an elderly woman with remarkable FDG uptake in BAT. Activation of BAT by a β3-adrenergic receptor agonist (mirabegron) prescribed for overactive bladder was suspected as the cause of the marked visualization of BAT in this patient.

Battery-less devices that operate on wireless power transfer have a relatively small operating area due to the limited transmit power from the source. Multitone based waveforms are considered to be one of the techniques to expand this operating range. However, they require some bandwidth to achieve this feature. By sharing the bandwidth required for multitone waveforms and superimposing information on the power, it is possible to transmit both power and information at the same time, which is known as simultaneous wireless information and power transfer (SWIPT). In this paper, we introduce a method of detecting signal by measuring peak to average power ratio (PAPR) in order to reduce the computational cost for frequency shift keying type SWIPT instead of observing frequency-domain signals by using fast Fourier transforms. Signal decoding is possible by seeing the PAPR difference as the frequencies of intermodulation signals varies with difference tone arrangement. We demonstrate this through circuit simulation with Advanced Design Systems (ADS) and show how many bits could encode for tones of 3 and 4. In addition, we categories which tone variations in the frequency domain would lead to obtaining a specific PAPR at the receiver end.

Low power devices driven by energy harvesting are limited in working range by transmit power restrictions. Power optimized waveforms (POWs) have been proposed as a way to achieve a longer working range without increasing average transmit power. In the ultra high frequency (UHF) band, bandwidth occupancy needs to be small enough to satisfy relevant regulations: thus the wideband POWs explored in some prior work may be less practical than narrowband POWs. This paper experimentally evaluates the performance of narrowband multi-sine based POWs, varying number of sines from 2 to 20 and occupied bandwidth of 10 kHz, 100 kHz, and 1 MHz-all narrowband from a regulatory perspective. Our key result is that additional sine waves improve voltage sensitivity, but not Power Conversion Efficiency. In our experiments, we observed the voltage sensitivity benefits of the multi-sine POWs to be most pronounced at a power level of -13 dBm; at signal levels significantly below (-30 dBm) or above (0 dBm) this level, their benefits diminish. Finally, we also observe that in a real system (the WISP 5.1, which includes a rectifier and DC-DC converter), voltage sensitivity is a much more complex function of waveform and signal power than in simpler idealized rectifiers. The sensitivity is a non-monotonic and complex function of the number of sines, occupied bandwidth, and signal strength.

To retrospectively assess a new CT finding of esophageal cancer, "early esophageal rim enhancement".Sixty-two patients with pathological proven esophageal squamous cell carcinoma who underwent dual phase CT imaging (arterial and venous phases) were enrolled. Two blinded observes independently evaluated presence of partial or circumferential enhancement of the esophageal periphery on arterial (early esophageal rim enhancement) and venous phase CT images. The radiological assessment was compared with the pathological T-stages. Agreement between the observers was also evaluated with a Cohen' kappa value.Pathologic results found 19, 12, 30 and 1 lesions, respectively for T1, T2, T3 and T4 stages. Agreement between two readers was substantial (κ=0.71). Esophageal rim enhancement was observed in 0, 4, 24 and 1 lesions respectively for T1, T2, T3 and T4 stages at the arterial phase, whereas no esophageal rim enhancement could be detected at the venous phase. Early esophageal rim enhancement was more frequently observed in T3/T4 lesions than T1/T2 lesions with statistical significance (p0.0001). The sensitivity, specificity and accuracy for the diagnosis of T3 or T4 lesion were 80.6%, 87.1% and 83.9%, respectively.Early esophageal rim enhancement may be helpful for assessing invasion into the adventitia.

The purpose of this study is to investigate radiologic findings of struma ovarii, and to correlate both CT and MR findings. MR images of 26 cases were retrospectively reviewed. Post-contrast enhanced T1-weighted images were available in 17 patients. CT images, including seven non-contrast and eleven post-contrast studies, were available for review in 13 cases. All 26 tumors appeared as well-defined cystic tumors with solid components, which were multilobulated surfaces in 19 and smooth surfaces in seven. Twenty-four was multicystic, whereas two were unilocular. The solid components were recognized as thickened septi or walls in 23 and a mass in three tumors. On T2-weighted images, loculi of prominent low intensity were recognized in 16 tumors. On T1-weighted images, the punctuate foci of high intensity were recognized in 24 tumors in or adjacent to the solid components. Ascites was present in only one lesion. In six of seven cases with non-contrast CT images, high attenuation areas were recognized. In five of these six tumors, high attenuation areas corresponded to the areas of prominent low intensity and the solid components on T2-weighted images. In seven cases with CT, curvilinear calcifications were recognized in the solid components. Struma ovarii typically presents as a lobulated multicystic lesion with solid components. The tumors frequently include loculi of low intensity on T2-weighted images and punctuate foci of high intensity on T1-weighted images. On CT, high attenuation areas and calcifications in the solid components are common findings.

Preceding this study, we observed two cases of concurrent postoperative gluteal skin and muscle damage with extremely high serum creatine kinase (CK) levels, both of which were unrelated to pressure-induced tissue injury. However, postoperative gluteal skin damage accompanied by gluteal muscle damage has not been previously reported and the association between gluteal skin damage, gluteal muscle damage and pressure-induced tissue injury has not previously been investigated. Therefore, we conducted this study to determine the postoperative incidence of gluteal skin damage associated with gluteal muscle damage and assess associations with postoperative serum CK levels and pressure-induced tissue injury. We prospectively evaluated postoperative incidence of gluteal skin damage and measured serum CK levels in 929 consecutive patients who underwent abdominal, urological or gynecological surgery at our hospital. Magnetic resonance imaging (MRI) of the pelvis was performed in 67 patients who consented. As a result, two of 929 patients developed postoperative gluteal skin damage accompanied by gluteal muscle damage. Gluteal muscle damage without gluteal skin damage was observed in 23 of the 67 patients who underwent MRI, and volumes of damaged gluteal muscle and postoperative serum CK levels were positively correlated. Both gluteal skin and muscle damage were distinguishable from pressure-induced tissue injury. Based on the results of this study, we could confirm the occurrence of postoperative gluteal skin damage, distinct from pressure sores, accompanied by gluteal muscle damage. We also revealed latent development of postoperative gluteal muscle damage, distinguishable from compression-induced tissue injury, without accompanying gluteal skin damage.

An image-sensor-based photo receiver for free-space optical communications, especially, ones employing indoor optical wireless LANs, has been developed. The receiver enables a compact and intelligent optical communication system through its two functional modes : image-sensing and communication. We clarified that the diffusion of photo-generated electrons determines the minimum total transimpedance gain of the amplifier and the maximum intensity of optical communication signals. A 50x50-pixel photo receiver with four independent communication-output channels was designed and fabricated with standard 0. 35 μm CMOS technology. To amplify optical data in the communication mode, it has in-pixel trans-impedance amplifiers and column-parallel main amplifiers. Experiments conducted with it showed that data rates of 50Mbps and 30Mbps were possible for wavelengths of 650nm and 830nm, respectively. Transimpedance gain varied from 660kΩ to 4.9MΩ for the data rate of 10Mbps. We also successfully captured images at a frame rate of 50Hz.

Clear cell carcinoma is typically a cystic mass containing multiple mural nodules. The cyst content typically shows high intensity on both T1- and T2-weighted images. Malignant Brenner tumor is typically a large multilocular cystic mass containing papillary projections and solid elements. Carcinosarcoma is typically a large heterogeneous mass, containing hemorrhage and necrosis.

Purpose: To investigate effects of hyoscine butylbromide (HBB) on the appearance of three zonal anatomy of the uterine corpus on T2-weighted images (T2WI). Materials and Methods: Sagittal T2WI of the pelvis were acquired before and after intramuscular administration of HBB with interval of 10 minutes in 22 healthy volunteers. By drawing polygonal regions of interest (ROIs), the uterine corpus was delineated into outer myometrium (OM), junctional zone (JZ), and endometrium (EM) in 20 subjects. Areas (mm2) and relative signal intensity (rSI) of each layer were compared between pre-HBB and post-HBB administration images by using paired t-tests. Histogram analysis was conducted for the uterine layers and changes were visualized. Results: Areas of OM were significantly increased (P = 0.014) and mean rSI of JZ and OM were significantly increased (P = 0.007 and 0.001, respectively) after administration of HBB. Histogram showed an increase in the number of pixels with higher rSI in the OM, which was considered to be caused by an increase in interstitial fluid and vascular dilatation. EM did not show significant changes. Conclusion: Layer-wise ROI analyses demonstrated changes in the area and rSI in T2WI of the uterus after HBB administration. Histogram analysis contributed to the investigation of signal changes. J. Magn. Reson. Imaging 2010;32:441–445. © 2010 Wiley-Liss, Inc.

The luster of human hair was studied in relation to the physical properties of hair surface. The luster was evaluated by means of Rod Method (visual evaluation) and Goniophotometry (instrumental evaluation). From the relationship between both methods, it was found that it may be possible to evaluate the luster of human hair by S value as a parameter.In order to clarify the factors which influence the luster of human hair, the physical properties of lusterous hair were compared with those of non-lustrous hair. The factors discussed here were as follows: (1) refraction index of hair surface, (2) Number and width of hair cuticles, (3) Number of cuticle cell layers. The physical properties, from root end to tip, of human hair were also investigated in relation to the luster.In addition, the effects of cosmetic treatments such as cold waving, brushing and blowing with heat were examined. Brushing and cold waving were found to have a great effect on the decrease of the luster.

We present a novel photo receiver for indoor optical wireless LANs based on a CMOS image sensor, which offers position detection of the other optical transceivers and 4-ch concurrent high-speed optical data acquisition. By use of an N-well/P-base photodiode with a diffusion carrier block structure, a data rate of 400 Mbps with BER less than 10/sup -12/ and low crosstalk in the-captured images are achieved. The total data rate is expected to be up to 1.6 Gbps.

The elimination reactions of hydrogen chloride from 1-chlorobutane and 2-chlorobutane over molten salts (ZnCl2, SnCl2, CuCl melts) have been studied by using both a microreactor and a conventional flow reactor. The preferential formation of cis-2-butene in the reaction of 2-chlorobutane can be explained in terms of the stereochemistry of the surface-adsorbed carbonium ion.