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1.
The value of flexible videoendoscopy as a biofeedback tool in conservative swallowing rehabilitation of patients suffering from aspiration after head and neck surgery was examined. For this purpose, the outcomes of conventional swallowing therapy and of swallowing therapy with support of videoendoscopic biofeedback were compared. In the first 40 days of swallowing therapy, videoendoscopic biofeedback significantly increased the chance of therapeutic success, shortening the period of functional rehabilitation in comparison to conventional swallowing therapy. Limitations of this visual biofeedback procedure are poor cognitive skills of the patient, rejection of the procedure by the patient and local factors that make the positioning of the endoscope difficult. 相似文献
2.
Toyokura M. Kodama H. Miyagoshi E. Okamoto K. Gion M. Minemaru T. Ohtani A. Araki T. Takeno H. Akiyama T. Wilson B. Aono K. 《Solid-State Circuits, IEEE Journal of》1994,29(12):1474-1481
A video DSP with macroblock-level-pipeline and a SIMD type vector-pipeline architecture (VDSP2) has been developed, using 0.5 μm triple-layer-metal CMOS technology. This 17.00 mm×15.00 mm chip consists of 2.5 M transistors, and operates at 100 MHz. The real-time encoder and decoder specified in the MPEG2 main profile at the main level can be realized with two VDSP2's and a motion estimation (ME) unit, and one VDSP2 respectively, at an 80 MHz clock rate, with a total power dissipation of 4.2 W at 3.3 V 相似文献
3.
Double-stranded DNA is one of functional polymers, but the large amounts of DNA sources, such as salmon milt and shellfish gonads, have been discarded as industrial wastes. Therefore, conversion of this discarded DNA to be a useful material would be beneficial to utilize the unique property of DNA. These materials including DNA have been prepared by mixing with the organic polymers, such as alginic acid, collagen, and chitosan. However, since these materials have consisted from entirely organic components, these do not have the mechanical strength for a material. So, we prepared the organic-inorganic hybrid materials by mixing DNA with silane coupling reagents bis(trimethoxysilylpropyl)amine or bis[(3-trimethoxysilyl)propyl]ethylenediamine. These hybrid materials with the flexibility were water-insoluble and resistant to hydrolysis by nuclease. In addition, the mechanical strength of this hybrid material was approximately twice as high as that of DNA without mixing with silane coupling reagents. Furthermore, the double-stranded DNA in the hybrid materials has been maintained in a B-form structure in aqueous solution. Thus, we demonstrated the utilization of DNA as a functional material. As a result, this material could selectively accumulate harmful DNA-intercalating compounds with the planar structure, such as dibenzo-p-dioxin, dibenzofuran, and ethidium bromide. Organic-inorganic hybrid material including double-stranded DNA has potential to serve as a useful biomaterial for medical, engineering, and environmental applications. 相似文献
4.
BACKGROUND AND OBJECTIVES: The stratum corneum of some of the scaly (parakeratotic) diseases was examined with light and scanning electron microscopy (SEM) with the purpose to reveal the importance of this layer in the diagnosis of some of the diseases associated with the formation of scales. MATERIALS AND METHODS: Two biopsies of the skin surface were taken: one, obtained from 80 patients with various parakeratotic scaly diseases and from 25 control subjects, was processed for light microscopy; the other biopsy for SEM was taken from 10 control subjects and 25 patients. The diagnoses of these patients were: psoriasis (5 patients), erythrodermic psoriasis (2 subjects), parapsoriasis (5 patients), pityriasis rubra pilaris (5 subjects), pityriasis rosea (3 subjects), and seborrheic dermatitis (5 subjects). RESULTS: The light microscopic studies showed that normal corneocytes are of polygonal shape with their largest diameter measuring 42 microns; these cells lacked nuclei. All parakeratotic cells appeared bizarre in shape, smaller than normal, and the cells contained a nucleus. With SEM, normal cells appeared relatively regular in size and shape, trabeculated, and had a flat surface. Cells examined in all the diseases revealed various sizes, outlines, and trabeculae. Specific surface patterns (print) of diseased cells were: "fish-scale" in psoriasis; "marbled" in parapsoriasis, "rocky stone" in pityriasis rubra pilaris; "heart-shaped" in seborrheic dermatitis, and semicrystalloid in pityriasis rosea. CONCLUSIONS: Parakeratosis is characterized not only by the retention of the nucleus in keratinocytes, but is also characterized by a cell of smaller size. The specific print of a disease helps in the diagnosis. The print will change with different stages of a disease. 相似文献
5.
Greedy versus social: resource-competing oscillator network as a model of amoeba-based neurocomputer
A single-celled amoeboid organism, the true slime mold Physarum polycephalum, exhibits rich spatiotemporal oscillatory behavior and sophisticated computational capabilities. The authors previously created
a biocomputer that incorporates the organism as a computing substrate to search for solutions to combinatorial optimization
problems. With the assistance of optical feedback to implement a recurrent neural network model, the organism changes its
shape by alternately growing and withdrawing its photosensitive branches so that its body area can be maximized and the risk
of being illuminated can be minimized. In this way, the organism succeeded in finding the optimal solution to the four-city
traveling salesman problem with a high probability. However, it remains unclear how the organism collects, stores, and compares
information on light stimuli using the oscillatory dynamics. To study these points, we formulate an ordinary differential
equation model of the amoeba-based neurocomputer, considering the organism as a network of oscillators that compete for a
fixed amount of intracellular resource. The model, called the “Resource-Competing Oscillator Network (RCON) model,” reproduces
well the organism’s experimentally observed behavior, as it generates a number of spatiotemporal oscillation modes by keeping
the total sum of the resource constant. Designing the feedback rule properly, the RCON model comes to face a problem of optimizing
the allocation of the resource to its nodes. In the problem-solving process, “greedy” nodes having the highest competitiveness
are supposed to take more resource out of other nodes. However, the resource allocation pattern attained by the greedy nodes
cannot always achieve a “socially optimal” state in terms of the public cost. We prepare four test problems including a tricky
one in which the greedy pattern becomes “socially unfavorable” and investigate how the RCON model copes with these problems.
Comparing problem-solving performances of the oscillation modes, we show that there exist some modes often attain socially
favorable patterns without being trapped in the greedy one. 相似文献
6.
Amoeba-based Chaotic Neurocomputing: Combinatorial Optimization by Coupled Biological Oscillators 总被引:1,自引:0,他引:1
Masashi Aono Yoshito Hirata Masahiko Hara Kazuyuki Aihara 《New Generation Computing》2009,27(2):129-157
We demonstrate a neurocomputing system incorporating an amoeboid unicellular organism, the true slime mold Physarum, known to exhibit rich spatiotemporal oscillatory behavior and sophisticated computational capabilities. Introducing optical
feedback applied according to a recurrent neural network model, we induce that the amoeba’s photosensitive branches grow or
degenerate in a network-patterned chamber in search of an optimal solution to the traveling salesman problem (TSP), where
the solution corresponds to the amoeba’s stably relaxed configuration (shape), in which its body area is maximized while the
risk of being illuminated is minimized.Our system is capable of reaching the optimal solution of the four-city TSP with a
high probability. Moreover, our system can find more than one solution, because the amoeba can coordinate its branches’ oscillatory
movements to perform transitional behavior among multiple stable configurations by spontaneously switching between the stabilizing
and destabilizing modes. We show that the optimization capability is attributable to the amoeba’s fluctuating oscillatory
movements. Applying several surrogate data analyses, we present results suggesting that the amoeba can be characterized as
a set of coupled chaotic oscillators.
相似文献
Kazuyuki AiharaEmail: |
7.
Shoki Tashiro Atsushi Tatsuma Masaki Aono 《Multimedia Tools and Applications》2017,76(21):22059-22076
We have witnessed 3D shape models abundant in many application fields including 3D CAD/CAM, augmented/mixed reality (AR/MR), and entertainment. Creating 3D shape models from scratch is still very expensive. Efficient and accurate methods for shape retrieval is essential for 3D shape models to be reused. To retrieve similar 3D shape models, one must provide an arbitrary 3D shape as a query. Most of the research on 3D shape retrieval has been conducted with a “whole” shape as a query (aka whole-to-whole shape retrieval), while a “part” shape (aka part-to-whole shape retrieval) is more practically requested as a query especially by mechanical engineering with 3D CAD/CAM applications. A “part” shape is naturally constructed by a 3D range scanner as an input device. In this paper, we focus on the efficient method for part-to-whole shape retrieval where the “part” shape is assumed to be given by a 3D range scanner. Specifically, we propose a Super-Vector coding feature with SURF local features extracted from the View-Normal-Angle image, or the image synthesized by taking account of the angle between the view vector and the surface normal vector, together with the depth-buffered image, for part-to-whole shape retrieval. In addition, we propose a weighted whole-to-whole re-ranking method taking advantage of global information based on the result of part-to-whole shape retrieval. Through experiments we demonstrate that our proposed method outperforms the previous methods with or without re-ranking. 相似文献
8.
9.
The role of ergosterol in yeast stress tolerance, together with heat shock proteins (hsps) and trehalose, was examined in a sterol auxotrophic mutant of Saccharomyces cerevisiae. Ergosterol levels paralleled viability data, with cells containing higher levels of the sterol exhibiting greater tolerances to heat and ethanol. Although the mutant synthesised hsps and accumulated trehalose upon heat shock to the same levels as the wild-type cells, these parameters did not relate to stress tolerance. These results indicate that the role of ergosterol in stress tolerance is independent of hsps or trehalose. 相似文献
10.
The liver microsomes of the Mongolian gerbilMeriones unguiculatus catalyzed the hydroxylation of various saturated fatty acids (C8−C18), alcohols (C12 and C16) and hydrocarbon (C12) to the corresponding ω- and (ω-1)-hydroxy derivatives. Lauric acid was hydroxylated most effectively among saturated fatty
acids and the order of activity as hydroxylation substrates was C12>C14>C13>C16>C10>C18>C8. The specific activity of laurate hydroxylation (5.99 nmol/mg microsomal protein/min) in gerbil liver microsomes was higher
than that observed in other species. 1-Dodecanol was also hydroxylated very effectively (4.58 nmol/mg microsomal protein/min)
by gerbil liver microsomes, but in general the hydroxylation rates for fatty alcohols were much lower than those for the corresponding
acids. It was found from both inhibitor and cofactor studies that the enzyme catalyzing the hydroxylation of fatty acids and
alcohols in the liver microsomes of the Mongolian gerbil was a typical cytochrome P-450-linked monooxygenase, and at least
two different cytochrome P-450 species were involved in the hydroxylation.
Presented in part at the AOCS annual meeting (a joint meeting with the Japan Oil Chemists' Society), Honolulu, Hawaii, May
1986. 相似文献