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Medication-related osteonecrosis of the jaw (MRONJ) is a severe adverse effect of antiresorptive and/or antiangiogenic agents. The standard treatment for MRONJ is conservative treatment and a surgical approach; however, its application remains controversial. This study aimed to identify the risk factors for poor prognosis and to help determine appropriate management. We retrospectively investigated factors associated with the prognosis of MRONJ in 119 patients. Relevant clinical data were obtained for all the patients. In computed tomography images, osteosclerosis, osteolysis, cortical perforation (buccal or lingual), periosteal reaction, and sequestration were observed. Univariate and multivariate analyses were used to evaluate the risk factors for poor prognosis. Multivariate analyses showed statistically significant associations between poor prognosis in patients with MRONJ and conservative treatment alone (hazard ratio [HR] 1.89), osteolysis (HR 4.67), and the absence of sequestration (HR 5.33). These results suggest that conservative treatment alone without clear objectives should be avoided, and osteolytic change could be the criteria for surgical intervention. As the boundary between the lesion and vital bone is indistinct, we recommend extensive surgery in cases which sequestration is unpredictable.

A standard treatment for osteoradionecrosis (ORN) has not yet been established because of the diversity. Therefore, identifying the risk factors for a poor prognosis is essential. This study retrospectively investigated the factors associated with the prognosis of ORN in 68 patients. Relevant clinical data of all patients were obtained. Of the patients, 16 who underwent extensive surgery underwent histopathological analysis. The necrotic changes of the anterior and posterior margins in the cortical and cancellous bones were investigated. Multivariate analyses showed statistically significant associations between poor prognosis in patients with ORN and high radiation dose (hazard ratio [HR] 1.15), orocutaneous fistula (HR 2.93), and absence of sequestration (HR 2.49). Histopathological analysis showed a viable anterior margin of the middle portion of the cortical bone for all recovered cases; in contrast, most cases (75%) with a poor prognosis showed necrotic changes. The anterior margin of the cancellous bone was viable and resilient to high irradiation, regardless of the prognosis. These results suggest that patients with orocutaneous fistula should receive early surgical intervention, even if the affected area is limited or asymptomatic. In extensive surgery, a sufficient safety margin of necrotic bone, particularly in the anterior region, is required to improve the prognosis.

In this study, we prospectively investigated the relationship between bone marrow edema (BME) and odontogenic cysts and explored the possibility of using dual-energy computed tomography (DECT) as an auxiliary tool for the diagnosis of odontogenic cysts.This cross-sectional study included 73 patients who underwent the DECT scan and surgery for odontogenic cysts or odontogenic tumors. The virtual noncalcium (VNCa) computed tomography (CT) values and CT values were measured at several sites. The predictor variable was diagnosis, and the other variables included age, sex, and sites. The primary outcome was VNCa CT value. Variables were tested using the chi-square test or the Kruskal-Wallis test. The VNCa CT and CT values were tested using the Scheffe test for multiple comparisons. All variables were analyzed as independent variables affecting the VNCa CT values around the lesion in the multiple regression analysis.There were 35 men and 38 women. The mean patient age was 50.0 ± 19.5 years (range: 8-86). The VNCa CT values (- 6.2 ± 34.3) around the lesion in patients with RCs were significantly higher than those in patients with dentigerous cysts (- 44.4 ± 28.6) and odontogenic keratocysts (- 67.3 ± 19.5). In multiple regression analysis, the VNCa CT values around the lesion showed a significant positive correlation with histological results (regression coefficient: - 0.605, P 0.001).The presence of BME is associated with radicular cysts, and DECT can be used as an auxiliary tool for radicular cyst diagnosis.

Filtered-x LMS algorithm and its relatives are the most popular control algorithms for ANC, because of their simplicity and practical performance. In these algorithms, the input signal to the algorithms is the signal filtered by the plant model. As well known, this causes two major problems, i.e., large computational burden and the delay of the signal path. We have proposed a new method without using the plant model to overcome the above problems for specific applications such as ventilation equipment. In this article, the relation between bandwidth of the reference signal and the order of adaptive filters is verified. It's also shown that proposed algorithm performs almost the same as MELMS (extended algorithm of filtered-x LMS for multichannel case) with much less computational load.

Musical transcription requires much burden even for specialists in the musical field therefore, many trials of automatic transcription have been being done actively. As musical signals are substantially time varying, we have investigated an LMS-based Fourier analyzer to accommodate time varying characteristics. In this article, frequency response of the above adaptive algorithm is brief! reviewed in order to provide insight of the adaptive algorithm. And then, the analyzing system of Kagura Japanese folk music musical signals, which converts analyzed results to the MIDI format, is described. Finally, results in MIDI format are converted to musical scores by using commercially available software in order to verify the validity of the system.

Acoustic feedback called howling of hearing aids causes annoying effect for users. The adaptive filter is used to model the acoustic feedback path and cancel its effect. In this article, firstly, conventional methods, the plain LMS method and the modified LMS method are briefly reviewed. And then, a problem of the conventional methods, namely, falling in biased estimation, is described. This is due to: (1) correlation between the input signal of the adaptive algorithm and the observation noise; (2) uneven frequency allocation for FIR type notch filter. In order to cope with the problems, a howling canceller with IIR notch filters, in which the input signal of the adaptive algorithm is quasi-whitened, is proposed. Finally, from extensive simulations, the validity of the proposed method is verified.

This paper presents a 100-kHz fifth-order Chebychev low-pass filter (LPF) using the proposed dynamic biasing (DB) technique which enables wide dynamic range under a low-supply voltage. The change of state variables in the internal nodes of the filter can be corrected by using a novel simplified scheme, avoiding the output transient owing to dynamic biasing. The filter, including an automatic frequency tuning system based on the voltage-controlled-filter (VCF) architecture and voltage reference circuit, is fabricated in a 0.18-mum standard CMOS technology with a 0.5-V threshold voltage and consumes 443 muW from a power supply of 0.6 V. The output noise and the in-band IIP3 are 575 pArms and 219 muA, respectively. The filter achieves a dynamic range of 89 dB.

A substrate noise cancellation circuit using cancellation points is proposed. Noise characteristic of a conventional cancellation circuit with divided points is analytically explained. A new version of active cancellation circuit with some points removed is proposed. Noise reduction of this version of active cancellation circuits is confirmed by computer simulations. Simulation and experimental results show using two cancellation points effectively reduces the noise.

A scheme for a low-voltage CMOS syllabic-companding log domain filter with wide dynamic range is proposed and its prototype is presented. A nodal voltage which is fixed in a conventional filter based on the dynamically adjustable biasing (DAB) technique is adapted for change of input envelope to achieve wide dynamic range. Externally linear and time invariant (ELTI) relation between an input and an output is guaranteed by a state variable correction (SVC) circuit which is also proposed for low-voltage operation. To demonstrate the proposed scheme, a fifth-order Chebychev low-pass filter with 100-kHz cutoff frequency is designed and fabricated in a standard 0.35-μm CMOS process. The filter has a 78-dB dynamic range and consumes 200-μW power from a 0.8-V power supply.