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The cerebellum is thought to have a variety of functions because it developed with the evolution of the cerebrum and connects with different areas in the frontoparietal cortices. Like neurons in the cerebral cortex, those in the cerebellum also exhibit strong activity during planning in addition to the execution of movements. However, their specific roles remain elusive. In this article, we review recent findings focusing on preparatory activities found in the primate deep cerebellar nuclei during tasks requiring deliberate motor control and temporal prediction. Neurons in the cerebellum are active during anti-saccade preparation and their inactivation impairs proactive inhibitory control for saccades. Experiments using a self-timing task show that there are mechanisms for tracking elapsed time and regulating trial-by-trial variation in timing, and that the cerebellum is involved in the latter. When predicting the timing of periodic events, the cerebellum provides more accurate temporal information than the striatum. During a recently developed synchronized eye movement task, cerebellar nuclear neurons exhibited periodic preparatory activity for predictive synchronization. In all cases, the cerebellum generated preparatory activity lasting for several hundred milliseconds. These signals may regulate neuronal activity in the cerebral cortex that adjusts movement timing and predicts the timing of rhythmic events.

In order to demonstrate the bleeding risk factors of GIST (gastrointestinal stromal tumor), we retrospectively investigated clinicopathological features between hemorrhagic (H group, 24 cases) and nonhemorrhagic GIST (NH group, 30 cases). In addition, we investigated features between the E group (6 cases) necessitating TAE (trans-catheter arterial embolization) and NE group (other 48 cases). Whereas H group partly includes high-risk grade GIST with chronic bleeding, meanwhile the E group (reflecting acute bleeding) is characterized by a highly enhanced mass with ulceration, comprising of smaller low-risk grade GIST. Amongst the 29 cases for forceps biopsy, which were 6 cases (21%) including one of E group, needed be hospitalized for postbiopsy bleeding. Acute bleeding in GIST may not be associated with malignant transformation. Postbiopsy bleeding or massive hemorrhage can also be encountered particularly in highly enhanced GIST with ulceration, even with a small and low-risk grade.

To explore contractile actions of angiotensin II (ATII) on the muscularis mucosae (MM) of the bladder, ATII-induced contractions were compared between MM and the detrusor smooth muscle (DSM) of the pig bladder by isometric tension recordings. Effects of ATII on spontaneous Ca2+ transients in MM were visualized using Cal-520 fluorescence. ATII receptor type 1 (ATR1) expression in MM and DSM was also examined by immunohistochemistry. ATII (1 nM-1 μM) caused phasic contractions of MM in a concentration-dependent manner, while ATII (10 nM-10 μM) had no or marginal effects on DSM contractility. ATII (100 nM)-induced MM contractions had an amplitude of approximately 70% of carbachol (1 μM)-induced or 90% of U46619 (100 nM)-induced contractions. Candesartan (10 nM), an ATR1 blocker, prevented the contractile effects of ATII (1 nM) in MM, while ATR1 immunofluorescence was greater in MM than DSM. ATII (10-100 pM) increased the frequency but not the amplitude of spontaneous Ca2+ transients in MM. Both urothelium-intact and -denuded MM strips developed comparable spontaneous phasic contractions, but ATII, carbachol and U46619-induced contractions were significantly larger in urothelium-denuded than urothelium-intact MM strips. In conclusion, the MM appears to have a much greater sensitivity to ATII compared with DSM that could well sense circulating ATII, suggesting that MM may be the predominant target of contractile actions induced by ATII in the bladder while the urothelium appears to inhibit MM contractility.

When waiting for a traffic light or dancing to a musical beat, we unconsciously keep track of elapsed time and precisely predict the timing of forthcoming sensory events. Temporal monitoring and prediction are integral to our daily life, and are regulated by neuronal processes through multiple global networks involving the frontoparietal cortices, the basal ganglia and the cerebellum. These processes are also known to be influenced by a variety of internal state and neuromodulators. Here, we review recent advance of research in the field.

Rhythmic events recruit neuronal activity in the basal ganglia and cerebellum, but their roles remain elusive. In monkeys attempting to detect a single omission of isochronous visual stimulus, we found that neurons in the caudate nucleus showed increased activity for each stimulus in sequence, while those in the cerebellar dentate nucleus showed decreased activity. Firing modulation in the majority of caudate neurons and all cerebellar neurons was proportional to the stimulus interval, but a quarter of caudate neurons displayed a clear duration tuning. Furthermore, the time course of population activity in the cerebellum well predicted stimulus timing, whereas that in the caudate reflected stochastic variation of response latency. Electrical stimulation to the respective recording sites confirmed a causal role in the detection of stimulus omission. These results suggest that striatal neurons might represent periodic response preparation while cerebellar nuclear neurons may play a role in temporal prediction of periodic events.

Predictive and tempo-flexible synchronization to an auditory beat is a fundamental component of human music. To date, only certain vocal learning species show this behaviour spontaneously. Prior research training macaques (vocal non-learners) to tap to an auditory or visual metronome found their movements to be largely reactive, not predictive. Does this reflect the lack of capacity for predictive synchronization in monkeys, or lack of motivation to exhibit this behaviour? To discriminate these possibilities, we trained monkeys to make synchronized eye movements to a visual metronome. We found that monkeys could generate predictive saccades synchronized to periodic visual stimuli when an immediate reward was given for every predictive movement. This behaviour generalized to novel tempi, and the monkeys could maintain the tempo internally. Furthermore, monkeys could flexibly switch from predictive to reactive saccades when a reward was given for each reactive response. In contrast, when humans were asked to make a sequence of reactive saccades to a visual metronome, they often unintentionally generated predictive movements. These results suggest that even vocal non-learners may have the capacity for predictive and tempo-flexible synchronization to a beat, but that only certain vocal learning species are intrinsically motivated to do it.

A 50-year-old man presented with bloody diarrhea and 25-kg weight loss over 3 months. Upper and lower endoscopy showed diffuse shaggy white villi in the duodenum and terminal ileum. In addition, capsule endoscopy and double-balloon enteroscopy revealed shaggy white villi in the entire small intestine. Histological examination of biopsy specimens found the lamina propria of the duodenal and intestinal mucosa to be densely infiltrated by rich foamy macrophages that were periodic acid-Schiff-positive. Electron microscopy showed numerous bacilli in the lamina propria. Tropheryma whipplei DNA was detected in the specimens by polymerase chain reaction. Based on these findings, the patient was diagnosed with Whipple's disease. He was treated with a 2-week course of ceftriaxone followed by trimethoprim-sulfamethoxazole. At the 2-month follow up, diffuse white shaggy villi improved dramatically.

An energy-discrimination K-edge X-ray computed tomography (CT) system is useful for increasing the contrast resolution of a target region by utilizing contrast media. The CT system has a cadmium telluride (CdTe) detector, and a projection curve is obtained by linear scanning with use of the CdTe detector in conjunction with an X-stage. An object is rotated by a rotation step angle with use of a turntable between the linear scans. Thus, CT is carried out by repetition of the linear scanning and the rotation of an object. Penetrating X-ray photons from the object are detected by the CdTe detector, and event signals of X-ray photons are produced with use of charge-sensitive and shaping amplifiers. Both the photon energy and the energy width are selected by use of a multi-channel analyzer, and the number of photons is counted by a counter card. For performing energy discrimination, a low-dose-rate X-ray generator for photon counting was developed; the maximum tube voltage and the minimum tube current were 110 kV and 1.0 microA, respectively. In energy-discrimination CT, the tube voltage and the current were 60 kV and 20.0 microA, respectively, and the X-ray intensity was 0.735 microGy/s at 1.0 m from the source and with a tube voltage of 60 kV. Demonstration of enhanced iodine K-edge X-ray CT was carried out by selection of photons with energies just beyond the iodine K-edge energy of 33.2 keV.

The aim of our study is to find impressional similarities between color combinations and music. In this paper, we analyze the correlation between musical and color impressions on the basis of a set of music words, the affective value scale of music (AVSM), and a set of color combination words, the color image scale. In the subjective assessments using the color image scale, 230 subjects answered questionnaires to choose the words that evoked the same impression as corresponding words in the AVSM. As a result, each word in the AVSM has been mapped onto the color image scale.

The single image super-resolution method can improve blur edges in a magnified image. However, it is difficult to improve the sharpness of a texture region in a magnified image since high frequency components of texture are different from others. In this paper, we propose super-resolution from a single image based on total variation (TV) regularization to improve sharpness of texture in magnified image. We use diverged components of total variation regularization to generate high frequency components. We show experimentally that the diverged components can improved the sharpness of texture in the magnified image. However, the noise as visual distortion occurs except for texture region by using the diverged components. Therefore, we propose a determination method for optimum that is a TV parameter to generate an appropriate high quality magnified image meaning an image with sharp texture and low noise in the edges and background. Our proposed method can generate sharper texture in a magnified image than Glasner’s method which is representation method of single image super-resolution.

音楽 (音) と色の関係は, 芸術, 科学の分野で古くから広く研究されてきている. 従来研究のほとんどは, 音楽の個々の構成要素のパラメータと色の関係を求めている. そこでは, 各構成要素から受ける印象には着目しているが, 音楽から受ける印象を深く考慮していないことが多い. さらに, 1楽曲に対して1色を関係付けていることがほとんどである. しかしながら, 楽曲にはその途中で曲調が変化するものが多い. そのため, 従来研究の成果から音楽と色を関係付けると, 感覚的に一致しないことが多かった.音楽の印象は楽曲の進行に伴い変化するものであり, 楽曲に合わせた色との対応を取る際, 楽曲の印象とその変化を考慮する必要があると考える. 本論文では, 楽曲から受ける印象の時系列変化に対応するために, 曲調変化を感知する箇所で楽曲を区切って印象評価を行い, その結果と先行研究で構築した「楽曲と配色間の共通印象を介したメディア変換モデル」を使用し, 感覚的一致度の高い楽曲と配色の組み合わせを実現する.本手法に基づいて, 各々の区間楽曲に対する一番強い印象のみを用いて配色との関係を求めた場合, 組み合わされた区間楽曲と配色の感覚的一致度は全体平均で約58%となった. そこで, 区間楽曲に対する全ての印象を用いて, 区間楽曲に適切な印象を総合的に判断可能なアルゴリズムを提案する. 本アルゴリズムに基づき区間楽曲と配色を組み合わせた結果, 一番強い印象のみを用いる方法と比較して, 約24%の感覚的一致度の向上があることが明らかとなった.

In order to improve the coding performance of subband image coding, the optimum frequency band partition (OFBP) based on the parameters of subband signal such as signal power or kurtosis has been proposed. However, the superiority of coding performances for both results using the above parameters is dependent with the contents of input image and the coding rate. In this paper, it is clarified that the similarity between the probability density functions (PDFs) in subband signals is closely related to the improvement of coding performance of the OFBP. We propose a new method to determine the optimum partition pattern on the 2-dimensional frequency domain using the Kullback–Leibler divergence (KLD) which is known as a similarity measurement between given two PDFs. It is seen in the experimental results that the PSNR of the proposed method is at most 3.0[dB] larger than the previous method in OFBP and JPEG at the same coding rate.

Although the discrete cosine transform (DCT) and wavelet transform have been used as effective techniques for reducing the redundancy of image waveforms, they have the problems of high complexity and causing block distortion. In this paper, a Haar wavelet transform with interband prediction is proposed that permits high-speed processing and which is suitable for coding as a subband decomposition technique since it generates little block distortion in the decoded images. the interband prediction method of this proposed transform method uses the derivative of the low-band waveform to predict the high-band waveform each time a band is split into two sub-bands. This results in a transform process that gives a prediction residual signal with lower entropy. During the inverse transform, the prediction coefficients obtained from the forward transform are used to predict the high-frequency waveforms and then, by adding the prediction residual, the original high frequency waveforms are reconstructed. Because the high-frequency waveforms are generated that smoothly interpolate the up-sampled, low-frequency waveforms, any block effects from this prediction technique are difficult to see in the decoded image. A detailed analysis of the proposed interband prediction process is performed by interpreting the proposed transform as a subband decomposition process that is based on the use of a symmetric short-kernel filter (SSKF) filter bank; then experiments are conducted that demonstrate its performance as a subband decomposition for coding of real image data and the possibility of progressive build-up of the decoded images. Results show that this transform method is effective for coding image data.

Purpose To develop computer-assisted image processing to identify the central sulcus from the MRI data sets in patients with brain tumors. Materials and Methods All MR images were acquired with a 3.0 Tesla scanner by three-dimensional (3D) spoiled gradient recalled acquisition using the steady state (SPGR) gradient-echo sequence and short inversion time inversion-recovery fast spin-echo sequence. The sulci were extracted automatically from reconstructed two-dimensional images of the cortical surface of 30 patients with brain tumors, and the extracted sulci were scored according to matching of the accepted anatomical features of the central sulcus. The candidates with the three highest scores were then superimposed on the 3D images. The correct position of the central sulcus was agreed by two senior neurosurgeons and one neuroradiologist. Results One of the three candidates corresponded to the central sulcus identified by the manual segmentation method for all 60 affected and unaffected hemispheres in the 30 patients. The candidate with the highest score coincided with the central sulcus in 26 of the 28 unaffected hemispheres and in 28 of the 32 affected hemispheres. Conclusion The proposed method of computer-assisted image processing can provide accurate guidance to identifying the central sulcus in patients with brain tumors. J. Magn. Reson. Imaging 2008. © 2008 Wiley-Liss, Inc.

A digital holographic data reconstruction method with data compression is proposed. We show the number of quantization level of a digital hologram can be reduced. By computer simulations it is confirmed that the method is especially useful for binary images. For gray scale images, we propose a bit plane decomposition method. By this method, we show both high reconstructed image quality and a high compression ratio can be achieved. This method is applicable to both a normal digital hologram and an encrypted digital hologram.

We are investigating the important physical factors for the reproduction of the high-order sensation, such as 'the sense of existence' and 'the naturalness', in a display of images. In our research, a key assessment word, 'image depth', is a useful indicator for the discovery of new physical factors. Focusing on the faithful reproduction of 'image depth', some physical factors of a display have been discovered. In this report, we will describe the newly discovered physical factor, the halation and the degradation of image quality. After observation of the images on two displays which have different types of coating on the surface of CRT, we have hypothesized that the halation around the surface of CRT might cause a serious degradation of image quality such as 'image depth'. Also we have considered that the coating might be one of important factors related to the halation characteristic. To confirm the above assumption, we prepared three types of CRT picture monitor which have different types of coating: 13 layer AR coating, 4 layer AR + non- glare coating and no-coating. The increase of luminance around a test target of white rectangle caused by the halation have been measured and the relationship between the halation characteristic and the reproduction of 'image depth' has been assessed.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Subband coding is important (1) to decompose an input signal into an adequate set of subbands considering the property of aninput signal and (2) to assign an adequate bits in proportion with the power of each subband signal. Investigation of auto-correlation characteristics of several kinds of images reveals us an isotropic correlation model. Based on this theoretical imagemodel, we have derived the optimum band partition that minimizes the quantization noise power of the reconstructed signal atthe receiving end. In order to apply the above theoretical optimum band partition to the image coding, we propose the optimumband partition scheme based on an idea of a set of band blocks, and we present the calculation algorithm with the low compu-tational complexity to determine the optimum band partition. Also, we propose two methods to exploit the non-stationarynature of images, and the filter bank configuration to realize the optimum band partition including these methods. The pro-posed optimum band partition shows better result than that of the blocking DCT in obtaining the higher compression rate andthe higher image quality.Keywords: Still image coding, Subband decomposition, Optimum band partition, Quantization noise power improvement,Band block, Non-stationary nature of image, Adaptive band partition

This paper is a revision of a paper presented at the SPIE conference on Algorithms and Systems for Optical Processing V, Jul. 2001, San Diego, California. The paper presented there appears (unrefereed) in SPIE Proceedings Vol. 4471. An encrypted digital holographic data reconstruction method with data compression is proposed. We show that the number of quantization levels of the digital hologram can be reduced. By computer simulations, we confirm that the method is especially useful for binary images. For gray-scale images, we propose a bit plane decomposition method. By this method, we show that both high reconstructed image quality and a high compression ratio can be achieved.