Uniform injection of 54Cr into solar nebula and temporal change of isotopic ratio in meteorites

第6回極域科学シンポジウム[OA] 南極隕石11月17日（火）　国立国語研究所 2階 講

RELATIONSHIP OF BASE-RUNNING PERFORMANCE WITH RUNNING DIRECTION AND ITS CHANGE

The purpose of this study was to clarify whether the running direction and its change affect the base-running performance. Thirty-five male baseball players performed 54.86 m (180 ft.) straight-line sprinting and distance-matched base-running, during which two dimensional positions of players were recorded with B Y Sports Tracking System. The results of this study revealed that the total base-running performance was probably affected by the running performance of the later running phase. In addition, smaller direction change before the first base and larger direction change after the first base maybe responsible for better performance in the entire base-running through better performance in the later section. These results would be useful for players and coaches who attempt to improve base-running performance

ACCURACY IN DETERMINING KINETIC PARAMETERS WITH FORCE PLATES EMBEDDED UNDER SOIL-FILLED BASEBALL MOUND

We developed a force measurement system embedded in a soil-filled mound for measuring ground reaction forces (GRF) acting on baseball pitchers and examined the accuracy of determining the point of force application (PFA) and kinetic parameters computed from GRF. Three 1.0 x 0.9 m2 force platforms were placed on the concrete foundation of an indoor sports facility and three bays were fixed onto the aluminum plates of the force plateorms. In each tray, clay-blocks were laid tightly and a mixture of red sand and volcanic-ash was used to make a smooth surface layer. The mean absolute error was 6.0 f 4.0 mm in determining PFA, less than 15.5 Ns (5% of the true value) in determining linear impulse. These results suggest that the present method is valid for measuring the PFA and GRF acting on the pitcher's legs for analyzing kinetics of pitching performances

Chironomidae collected at the seashore in Kume Island, Japan

Local residents and tourists of Kume Island suffer from the biting of Leptoconops taiwanensis (Lien, Lin & Weng 1998) (Ceratopogonidae), a species known as asa-mushi (sea lettuce bug). Because L. taiwanensis bites tend to occur while harvesting sea lettuce, some locals mistakenly believe that L. taiwanensis inhabits the sea lettuce. The objectives of the current study are to (i) identify the chironomid species inhabiting the sea lettuce, (ii) determine the distribution of the larvae, and (iii) perform a faunistic investigation of Chironomidae at Shinri Beach. Only one male chironomid species, Ainuyusurika tuberculatum (Tokunaga, 1940), emerged from the samples taken from the beach. The density of chironomid larvae was the highest in the presence of sea lettuce. A total of 53 males were collected using light traps, of which we identified males of seven genera and seven species belonging to three subfamilies. No L. taiwanensis were collected in this study

Computer-aided diagnosis for osteoporosis based on trabecular bone analysis using panoramic radiographs

Background: Mandibular bone on panoramic radiographs has been proven to be useful for identifying postmenopausal women with low skeletal bone mineral density. One of the important parts of mandibular bone is trabecular bone. Trabecular bone architecture is one of the factors that governs bone strength and may be categorized as a contributor to bone quality. Purpose: The purposes of this study were to develop a computer-aided system for measuring trabecular bone line strength on panoramic radiographs in identifying postmenopausal women with osteoporosis and to clarify the diagnostic efficacy of the system. Methods: Reduction and expansion of trabecular bone sample images using a two level Gaussian pyramid for removing noises and small segments were first introduced. Then, line strength at each pixel was calculated based on its existence on the trabecular bone with emphasizes line segment which has similar orientation with the root of tooth. The density was measured with respect to line strength of segment structure which has similar orientation with the root of tooth, either on the left and the right in the mandibular bone. Number of pixels in the line segment area was compared with a threshold value to determine whether normal or osteoporosis. Results: From experiment on 100 data, the accuracy of 88%, sensitivity of 92%, and specificity of 86.7% were achieved. Conclusion: The computer-aided system of trabecular bone analysis may be useful for detecting osteoporosis using panoramic radiographs.Latar belakang: Tulang mandibula pada panoramik radiografi telah banyak diteliti dan terbukti mampu digunakan untuk mengidentifikasi wanita pasca menopause dengan menggunakan bone mineral density rendah. Salah satu bagian tulang mandibula yang penting adalah tulang trabekula. Arsitektur tulang trabekula merupakan salah satu dari faktor-faktor yang mempengaruhi kekuatan tulang dan dapat digolongkan sebagai kontributor bagi kualitas tulang. Tujuan: Penelitian ini bertujuan untuk membangun sebuah sistem dengan bantuan komputer untuk mengukur kekuatan garis pada tulang trabekula dan menggunakannya untuk mendeteksi osteoporosis pada wanita postmenopause. Metode: Dilakukan sampling pada sebagian tulang mandibular yang menghasilkan sebuah sampel citra. Sampel citra ini selanjutnya diperbaiki dari derau (noise) dengan menggunakan piramida Gaussian dua level. Kekuatan garis pada tiap piksel dihitung berdasarkan orientasi segmen garis tulang trabekula yang sejajar dengan akar gigi. Setelah dilakukan binerisasi, luasan segmen yang dihasilkan dihitung dan dibandingkan dengan sebuah nilai ambang. Bila luasan melebihi nilai threshold maka dikategorikan sebagai normal. Sebaliknya bila luasan dibawah nilai threshold, dikategorikan sebagai osteoporosis. Hasil: Berdasarkan eksperimen terhadap 100 data, sistem mampu mencapai akurasi identifikasi sebesar 88%, sensitivitas 92%, dan spesifisitas 86,7%. Kesimpulan: Sistem analisa trabecular bone dengan bantuan komputer ini dapat digunakan oleh para dokter gigi untuk mendeteksi osteoporosis menggunakan panoramik radiografi.</p

Serial MRI Features of Canine GM1 Gangliosidosis: A Possible Imaging Biomarker for Diagnosis and Progression of the Disease

GM1 gangliosidosis is a fatal neurodegenerative lysosomal storage disease caused by an autosomal recessively inherited deficiency of β-galactosidase activity. Effective therapies need to be developed to treat the disease. In Shiba Inu dogs, one of the canine GM1 gangliosidosis models, neurological signs of the disease, including ataxia, start at approximately 5 months of age and progress until the terminal stage at 12 to 15 months of age. In the present study, serial MR images were taken of an affected dog from a model colony of GM1 gangliosidosis and 4 sporadic clinical cases demonstrating the same mutation in order to characterize the MRI features of this canine GM1 gangliosidosis. By 2 months of age at the latest and persisting until the terminal stage of the disease, the MR findings consistently displayed diffuse hyperintensity in the white matter of the entire cerebrum on T2-weighted images. In addition, brain atrophy manifested at 9 months of age and progressed thereafter. Although a definitive diagnosis depends on biochemical and genetic analyses, these MR characteristics could serve as a diagnostic marker in suspect animals with or without neurological signs. Furthermore, serial changes in MR images could be used as a biomarker to noninvasively monitor the efficacy of newly developed therapeutic strategies

The nucleocytoplasmic shuttling protein CIZ reduces adult bone mass by inhibiting bone morphogenetic protein–induced bone formation

Osteoporosis is a major health problem; however, the mechanisms regulating adult bone mass are poorly understood. Cas-interacting zinc finger protein (CIZ) is a nucleocytoplasmic shuttling protein that localizes at cell adhesion plaques that form where osteoblasts attach to substrate. To investigate the potential role of CIZ in regulating adult bone mass, we examined the bones in CIZ-deficient mice. Bone volume was increased and the rates of bone formation were increased in CIZ-deficient mice, whereas bone resorption was not altered. CIZ deficiency enhanced the levels of mRNA expression of genes encoding proteins related to osteoblastic phenotypes, such as alkaline phosphatase (ALP) as well as osterix mRNA expression in whole long bones. Bone marrow cells obtained from the femora of CIZ-deficient mice revealed higher ALP activity in culture and formed more mineralized nodules than wild-type cells. CIZ deficiency enhanced bone morphogenetic protein (BMP)–induced osteoblastic differentiation in bone marrow cells in cultures, indicating that BMP is the target of CIZ action. CIZ deficiency increased newly formed bone mass after femoral bone marrow ablation in vivo. Finally, BMP-2–induced bone formation on adult mouse calvariae in vivo was enhanced by CIZ deficiency. These results establish that CIZ suppresses the levels of adult bone mass through inhibition of BMP-induced activation of osteoblasts