567 research outputs found
An approach for the non-cutoff Boltzmann equation in
In the paper, we develop an approach to construct global
solutions to the Cauchy problem on the non-cutoff Boltzmann equation near
equilibrium in . In particular, only smallness of
with is imposed on initial data , where
is the Fourier transform in space variable. This
provides the first result on the global existence of such low-regularity
solutions without relying on Sobolev embedding in case of the whole space. Different from the use of
sufficiently smooth Sobolev spaces in those classical results by
Gressman-Strain and AMUXY, there is a crucial difference between the torus case
and the whole space case for low regularity solutions under consideration. In
fact, for the former, it is enough to take the only norm corresponding
to the Weiner space as studied in Duan-Liu-Sakamoto-Strain. In contrast, for
the latter, the extra interplay with the norm plays a vital role in
controlling the nonlinear collision term due to the degenerate dissipation of
the macroscopic component. Indeed, the propagation of norm helps gain
an almost optimal decay rate of the
norm via the time-weighted energy estimates in the spirit of the idea
of Kawashima-Nishibata-Nishikawa and in turn, this is necessarily used for
establishing the global existence.Comment: 38 page
Statistical Analysis of Pressure Fluctuations in Vertical Two-Phase Flow
An experimental study was conducted on pressure fluctuations in vertical two-phase air-water flow. Statistical analysis of measured fluctuations was used to identify flow regimes in two-phase flow. Random ripple fluctuations were observed in bubbly flow. In slug and churn flows, however, violent oscillations were caused by the periodic passage of liquid and gas slugs. These oscillations-were weakened with a further in-crease of gas flowrate, and small ripple fluctuations again appeared in annular flow
Central Mandibular Reconstruction by Semiopen Wedge Osteotomy Double-barrel Fibula Flap for a Slim Aesthetic Appearance
Mandibular reconstruction involving the central segment after malignant tumor resection requires the achievement of both functional and aesthetic quality. Three-dimensional reproduction based on the concept of a double arc composed of a marginal arc and an occlusal arc is important. Most reports of fibula flaps applied three-segmented closed wedge fibula osteotomy (bilateral and central segments); however, the aesthetic outcome sometimes became too stout for female patients because of the large central segment. We performed four-segmented fibula osteotomy for a 78-year-old woman using a semiopen wedge technique characterized by a half-open wedge and half-closed wedge. This procedure obtained a slim mandibular contour and made double-barrel reconstruction easier to apply. We used titanium plates that were prebent according to the shape of a three-dimensional model constructed from CT data. Small bone cortex fragments made from a surplus fibula segment were inserted in a half-opened area. The build-up preparation for central mandibular reconstruction was all performed at the lower leg area before cutting the peroneal pedicle. This prefabricated double-barrel fibula free flap was transferred to the mandibular defect with arterial and venous anastomosis to the right superior thyroid artery, right external jugular vein, and right common facial vein. Although the patient was nearly 80 years of age, the bone segments, including free cortex tips, were fused with smooth remodeling. Semiopen wedge osteotomy can be a key to reproducing an aesthetically slim feminine chin with a functional height of mandibular bone maintained for stability of the dental prosthesis
Learning of a Nonlinear Function using a EBP Learning Algorithmu and its Application to Adaptive Control
臨床用CTを用いた上腕骨大結節の領域別骨梁微細構造解析
BACKGROUND:
In arthroscopic surgery, the suture anchor technique has become popular for rotator cuff repair. Preoperative evaluation of the bone microstructure is of utmost importance because, especially in elderly patients, osteoporotic changes may cause anchor pullout, which results in failure of rotator cuff repair. Many groups have reported humeral microstructural analysis; however, most studies were experiments using porcine specimens or human cadavers. In this study, we used multidetector row computed tomography to successfully perform in vivo evaluation of the bone microstructure of the humeral greater tuberosity in patients with rotator cuff tears.
METHODS:
Ten patients were examined. Regions of interest were defined in six quadrants of the greater tuberosity (medial, lateral, and far lateral rows of the anterior and posterior areas). The local bone mineral density and the trabecular microstructural parameters, including the mean bone volume to total volume (BV/TV), trabecular thickness, trabecular separation, and structure model index (SMI), were measured using bone analysis software.
RESULTS:
The BV/TV of the posteromedial region was highest and the SMI of the posteromedial region was lowest. These findings suggest that the bone quality of the posteromedial portion is the highest within the greater tuberosity.
CONCLUSION:
Because the bone quality may be correlated with the pullout strength of suture anchors, our method can help to understand the individual and regional variance in bone quality and may lead to the creation of personalized surgical protocols.博士(医学)・乙第1360号・平成27年5月28日© 2014 Sakamoto et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated
A comparison of the usefulness of nuclear beta‐catenin in the diagnosis of desmoid‐type fibromatosis among commonly used anti‐beta‐catenin antibodies
Desmoid-type fibromatosis (DF) is a locally aggressive but non-metastatic (myo)fibroblastic neoplasm. A hallmark of the tumor is nuclear positivity for beta-catenin in immunohistochemistry due mostly to CTNNB1 mutations. However, a recent study has reported that even beta-catenin ‘nuclear-negative’ DFs can harbor CTNNB1 mutations and that the positive ratio of nuclear beta-catenin in DF is different among antibodies. Here, we reviewed soft tissue lesions for which the possibility of DF was considered and compared the sensitivity and specificity of nuclear beta-catenin for the diagnosis of DF among commonly used anti-beta-catenin antibodies, i.e., clone beta-catenin 1, 17C2 and 14. We analyzed 26 cases of DF, 28 cases of benign fibroblastic lesions, and 27 cases of other soft tissue tumors. The sensitivity and specificity of nuclear beta-catenin for the diagnosis of DF were different among antibodies; 54% and 98% in clone beta-catenin 1, 85% and 84% in 17C2, and 96% and 62% in 14. IHC of LEF1 showed comparable results with IHC of beta-catenin, with a sensitivity of 88% and specificity of 76%. Additionally, when beta-catenin 1 was used, DFs showed characteristic dotted cytoplasmic staining, often appearing as rings. Our results might be helpful for making a correct diagnosis of DF
肩甲切痕のバリエーション-3DCT による検討
BACKGROUND:Although cadaveric studies have revealed suprascapular notch shape variations, few have investigated the association between suprascapular notch variation and age or gender. The purpose of this study was to investigate suprascapular notch shape variations by use of three-dimensional computed tomography (3DCT) and to determine if there was any association with age or gender.METHODS:Three-dimensional CT images of 762 shoulders of 762 patients were analyzed in this study. Participants comprised 404 men and 358 women, with an average age of 58.2 ± 19.1 years. Suprascapular notch shape variations were classified into six types on the basis of Rengachary's classification.RESULTS:Of the total study population, 11.4% were classified as type I, 23.5% as type II, 30.1% as type III, 14.8% as type IV, 15.9% as type V, and 4.3% as type VI. Average age was 56.5 ± 20.5 years for type I, 57.0 ± 19.5 years for type II, 55.5 ± 20.0 years for type III, 56.4 ± 18.5 years for type IV, 65.5 ± 14.4 years for type V, and 68.0 ± 13.4 years for type VI. Statistically significant age differences were found between types I-IV and V, between types I-IV and VI, and between the non-ossification group (types I-IV) and the ossification group (types V and VI). Male-to-female ratio among each type, and between the non-ossification group and the ossification group, were not statistically significantly different.CONCLUSIONS:Our results suggest that transverse scapular ligament ossification is associated with aging whereas individual variation explains differences among types I, II, III, and IV. Three-dimensional CT provides useful information for arthroscopic resection of the transverse scapular ligament, when the wide variety of suprascapular notch shape variations is considered.LEVEL OF EVIDENCE:Level IV.博士(医学)・乙第1361号・平成27年5月28日© Springer International Publishing AG, Part of Springer Science+Business Media. The definitive version is available at " http://dx.doi.org/10.1007/s00776-014-0636-x "© The Japanese Orthopaedic Association 201
Human cultured epidermis accelerates wound healing regardless of its viability in a diabetic mouse model
Allogeneic cultured epidermis (allo-CE) is a cultured keratinocyte sheet manufactured from donor cells and promotes wound healing when used in deep dermal burns, donor sites, and chronic ulcers and serves as a wound dressing. Allo-CE is usually cryopreserved to be ready to use. However, the cryopreservation procedure will damage the cell viability, and the influence of Allo-CE, according to its viability or wound healing process, has not been evaluated sufficiently. In this study, we aimed to prove the influence of keratinocyte viability contained in allo-CEs on wound healing. We prepared CEs with Green’s method using keratinocytes obtained from a polydactyly patient and then prepared four kinds of CEs with different cell viabilities [fresh, cryopreserved, frozen, and FT (freeze and thaw)]. The cell viabilities of fresh, cryopreserved, frozen, and FT CEs were 95.7%, 59.9%, 16.7%, and 0.0%, respectively. The four CEs had homogeneous characteristics, except for small gaps found in the FT sheet by transmission electron microscopy observation. The four CEs were applied on the full-thickness skin defect of diabetic mice (BKS.Cg-Dock 7m +/+ Leprdb/Jcl), and the wound area and neoepithelium length were evaluated on days 4, 7, and 14. As a result, FT CEs without viable cells similarly promoted epithelialization on days 4 and 7 (p<0.05) and accelerated wound closure on day 7 (p<0.01) as fresh CEs compared with the control group. In conclusion, the promoting effect of allo-CE on wound healing does not depend on cell viability. Lyophilized CEs may be a suitable wound dressing with a long storage period at room temperature
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