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We have improved an ozone DIfferential Absorption Lidar (DIAL) system, originally developed in March 2010. The improved DIAL system consists of a Nd:YAG laser and a 2 m Raman cell filled with 8.1×105 Pa of CO2 gas which generate four Stokes lines (276, 287, 299, and 312 nm) of stimulated Raman scattering, and two receiving telescopes with diameters of 49 and 10 cm. Using this system, 44 ozone profiles were observed in the 1-6 km altitude range over Saga (33.24° N, 130.29° E) in 2012. Highozone layers were observed at around 2 km altitude during April and May. Ozone column amounts within the 1-6 km altitude range were almost constant (19.1DU on average) from January to March, and increased to 26.7DU from late April to July. From mid-July through August, ozone column amounts decreased greatly to 14.3DU because of exchanges of continental and maritime air masses. Then in mid- September they increased again to 22.1DU within 1-6 km, and subsequently decreased slowly to 17.3 DU, becoming almost constant by December. The Meteorological Research Institute's chemistry- climate model version 2 (MRI-CCM2) successfully predicted most of these ozone variations with the following exceptions. MRI-CCM2 could not predict the high-ozone volume mixing ratios measured at around 2 km altitude on 5 May and 11 May, possibly in part because emissions were assumed in the model to be constant (climatological data were used). Ozone volume mixing ratios predicted by MRICCM2 were low in the 2-6 km range on 7 July and high in the 1-4 km range on 19 July compared with those measured by DIAL. [ABSTRACT FROM AUTHOR]

Abstract: Octacalcium phosphate (OCP) is supposed to be a precursor of biological apatite such as bone and tooth. We have examined experimentally whether synthetic octacalcium phosphate could be used as an effective scaffold to regenerate bone if implanted in vivo. We have fabricated the granules of the synthetic OCP. It was ascertained that the implanted OCP provided the core for nucleating multiple osteogenic sites and orthotopically induced bone formation and enhanced bone regeneration. OCP was resorbed by multinucleated giant cells that shared some ultrastructural characteristics with osteoclasts. The implanted OCP was more resorbable and replaced by newly formed bone than other calcium phosphate compounds, commonly used bone graft substitutes, such as synthetic hydroxyapatite (HA) and ?-tricalcium phosphate (?-TCP). OCP sustained and delivered growth factors such as bone morphogenetic protein-2 (BMP-2) or transforming growth factor-?1 (TGF-?1) and the composites OCP with cytokine enhanced bone regeneration significantly. Therefore, the synthetic OCP would be an effective scaffold to bone regenerative therapy. [Copyright &y& Elsevier]

Simulations of Arctic denitrification using a 3-D chemistry-microphysics transport model are compared with observations for the winters 1994/1995, 1996/1997 and 1999/2000. The model of Denitrification by Lagrangian Particle Sedimentation (DLAPSE) couples the full chemical scheme of the 3-D chemical transport model, SLIMCAT, with a nitric acid trihydrate (NAT) growth and sedimentation scheme. We use observations from the Microwave Limb Sounder (MLS) and Improved Limb Atmospheric Sounder (ILAS) satellite instruments, the balloon-borne Michelsen Interferometer for Passive Atmospheric Sounding (MIPAS-B), and the in situ NOy instrument on-board the ER-2. As well as directly comparing model results with observations, we also assess the extent to which these observations are able to validate the modelling approach taken. For instance, in 1999/2000 the model captures the temporal development of denitrification observed by the ER-2 from late January into March. However, in this winter the vortex was already highly denitrified by late January so the observations do not provide a strong constraint on the modelled rate of denitrification. The model also reproduces the MLS observations of denitrification in early February 2000. In 1996/1997 the model captures the timing and magnitude of denitrification as observed by ILAS, although the lack of observations north of ∼67° N make it difficult to constrain the actual timing of onset. The comparison for this winter does not support previous conclusions that denitrification must be caused by an ice-mediated process. In 1994/1995 the model notably underestimates the magnitude of denitrification observed during a single balloon flight of the MIPAS-B instrument. Agreement between model and MLS HNO3 at 68 hPa in mid-February 1995 was significantly better. Sensitivity tests show that a 1.5 K overall decrease in vortex temperatures or a factor 4 increase in assumed NAT nucleation rates produce the best statistical fit to MLS observations. Both adjustments would be required to bring the model into agreement with the MIPAS-B observations. The agreement between the model and observations suggests that a NAT-only denitrification scheme (without ice), which was discounted by previous studies, must now be considered as one mechanism for the observed Arctic denitrification. The timing of onset and the rate of denitrification remain poorly constrained by the available observations. [ABSTRACT FROM AUTHOR]

Mandibular distraction osteogenesis is a welldeveloped clinical modality for the treatment of craniofacial deformities and dental arch discrepancies, in combination with orthodontic treatment. However, in our previous study, orthodontic tooth movement into the distraction gap caused severe root resorption. The present study aimed to clarify the osteoclastogenic activity of cells in the distraction gap. We hypothesized that the gene expression of osteoclastogenic- and osteoclast-supporting molecules in osteoblasts and stromal cells would increase at distraction sites during the consolidation period. An animal model experiment involving rabbits was designed for mandibular distraction osteogenesis and subjected to in situ hybridization analysis. The number of osteoclasts was larger in the distraction gap during the early consolidation period than in normal controls, due to an increase of gene expression for osteoclastogenic cytokines in osteoblasts. It was concluded that osteoclastogenic and osteoclastic activities are stimulated at distraction sites during the early consolidation period. [ABSTRACT FROM AUTHOR]

Periodontal ligament tissue is remodeled on both the tension and compression sides of moving teeth during orthodontic tooth movement. The present study was designed to clarify the hypothesis that the expression of MMP-8 and MMP-13 mRNA is promoted during the remodeling of periodontal ligament tissue in orthodontic tooth movement. We used the in situ hybridization method and semi-quantitative reverse-transcription/polymerase chain-reaction analysis to elucidate the gene expression of MMP-8 and MMP-13 mRNA. Expression of MMP-8 and MMP-13 mRNA transiently increased on both the compression and tension sides during active tooth movement in vivo. The gene expression of MMP-8 and MMP-13 was induced by tension, while compression indirectly promoted the gene expression of MMP-8 and MMP-13 through soluble factors in vitro. Thus, we concluded that the expression of MMP-8 and MMP-13 is differentially regulated by tension and compression, and plays an important role in the remodeling of the periodontal ligament. [ABSTRACT FROM AUTHOR]

The present study was designed to investigate mRNA expression of matrix metalloproteinase-8 (MMP-8) and MMP-13 in forming periodontium during tooth eruption in the rat. RT-PCR for the decalcified paraffin sections indicated expression of MMP-8 and MMP-13 in the periodontal tissues. In situ hydridization demonstrated expression of MMP-8 in osteoblasts, osteocytes, periodontal ligament cells, cementoblasts, and cementocytes along with collagen types I and III. In contrast, transcripts of MMP-13 were confined to a small population of osteoblasts and osteocytes in alveolar bone. The results suggested that MMP-8 may be involved in remodeling the periodontium during tooth eruption, and its expression may be coordinated with that of collagen types I and III, whereas the participation of MMP-13 may be rather limited. [ABSTRACT FROM AUTHOR]