A Computational Approach To Predict Warp Of Sawn Lumber Due To Residual Growth Stress In A Log

A tree generates a complicated stress distribution inside the stem during its formation, which is called 'residual growth stress (RGS)'. The RGS often induces warp in a sawn lumber such as bow, crook, and other deformation, which causes severe losses of materials and benefits in the sawmill industry. Generally, warp becomes more serious in the lumber 'without pith' than in the lumber 'with pith'. In Japan, 50% of conifer plantations are ready to produce large-diameter logs of which diameter is more than 30 cm. The use of those logs inevitably leads to the production of the lumber 'without the pith', so we are concerned about the problems due to lumber warp in future sawmill industry using largediameter logs. Based on those practical background, this study presents a computational procedure to predict warp of the squared lumber, such as a beam, a bearer, and so forth, when those lumbers are sawn from the log and/or the thick plank. Using the derived procedure, 2-D patterns of the RGSs in the sawn lumbers and their changes during sawing processes are simulated. Simulated results will be experimentally verified by measuring the warp of the sawn lumber, as well as by measuring the RGS distributions in a log

Jet-Precipitation Relation and Future Change of the Mei-Yu-Baiu Rainband and Subtropical Jet in CMIP5 Coupled GCM Simulations

Through extensive modeling efforts, it has been established that the ongoing global warming will increase the overall precipitation associated with the East Asian summer monsoon, but the future change of its spatial distribution has not reached a consensus. In this study, meridional shifts of the mei-yu-baiu rainband are studied in association with the subtropical jet by using outputs from atmosphere-ocean coupled climate models provided by CMIP5. The models reproduce observed associations between the jet and precipitation over wide time scales from synoptic to interannual. The same relation is found in intermodel differences in simulated climatology, so that the meridional locations of the jet and baiu precipitation are positively correlated. The multimodel-mean projection suggests that the both are shifted southward by the late twenty-first century. This shift is not inconsistent with the projected tropical expansion, not only because the change is local but also because the projected tropical expansion occurs mainly in the Southern Hemisphere. No significant future change in the continental mei-yu precipitation location is identified, which might be because the jet change is weak there. For comparison, the summertime Atlantic jet position, which shifts northward, is investigated briefly. This study suggests that the future change of the subtropical jet is an important aspect to investigate possible future changes of the baiu rainband, and it prompts further studies including the role of the ocean

Prevention of Ornithine Cytotoxicity by Nonpolar Side Chain Amino Acids in Retinal Pigment Epithelial Cells

PURPOSE. To investigate the effect of amino acids on ornithine cytotoxicity in ornithine-␦-aminotransferase (OAT)-deficient human retinal pigment epithelial (RPE) cells as an in vitro model of gyrate atrophy (GA) of the choroid and retina. METHODS. RPE cells were treated with 0.5 mM 5-fluoromethylornithine (5-FMOrn), a specific and irreversible OAT inhibitor. OAT-deficient RPE cells were incubated with 10 mM ornithine in the presence of 20 mM of 1 of 18 amino acids or 10 mM 2-amino-2-norbornane-carboxylic acid (BCH), a conventional inhibitor of the amino acid transporter system L. Ornithine cytotoxicity and cytoprotective effects of each amino acid was evaluated with a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay 72 hours after treatment with ornithine in OAT-deficient RPE cells. Ornithine incorporation into RPE cells was evaluated using DL discovered that the biochemical abnormalities of this disorder are hyperornithinemia and overflow ornithinuria. Further, the finding of an association between hyperornithinemia and GA led to the discovery of an enzyme defect, a deficiency of the mitochondrial matrix enzyme ornithine-␦-aminotransferase (OAT). 3-5 We have reported that inactivation of OAT in human retinal pigment epithelial (RPE) cells by 5-fluoromethylornithine (5-FMOrn), a specific irreversible inhibitor of OAT, 6 makes them susceptible to ornithine, leading to cell death. 7 A human hepatoma cell line, HepG2, and a fibroblast cell line, WI-38, which possess OAT activity comparable to that of RPE cells, are not affected by ornithine when OAT is inactivated by 5-FMOrn, suggesting that ornithine cytotoxicity toward 5-FMOrn-treated RPE can be used as an in vitro model of GA. We have also demonstrated that proline prevents ornithine-induced cell death. Mammalian cells have two biosynthetic pathways for proline and share a common intermediate, L-⌬ 1 -pyrroline-5-carboxylic acid (P5C), which is formed from ornithine by OAT and from glutamic acid by P5C synthase. In a previous study, ornithine almost completely blocked P5C synthase and decreased the incorporation of proline derived from glutamic acid into protein in fibroblasts cultured from patients with GA 8 ; however, the mechanisms of ornithine cytotoxicity in OAT-deficient RPE cells and cytoprotection by proline remain to be elucidated. In the course of our earlier experiments, we noticed that 5-FMOrn-treated RPE cells are damaged by ornithine when cultured in Ham F12 medium, whereas they are not affected by ornithine in Dulbecco's modified Eagle's (DME) medium devoid of proline. Those unexpected results prompted us to investigate the effect of other amino acids on ornithine cytotoxicity and incorporation of ornithine in human RPE cells to clarify the mechanisms of ornithine cytotoxicity. From the present results, we report that most of the nonpolar and uncharged polar side chain amino acids tested prevented ornithine cytotoxicity through L-type amino acid transporters. MATERIAL AND METHODS Cell Culture A human RPE cell line, hTERT-RPE, previously established by gene transfer of human telomerase reverse transcriptase cDNA, 9 was kindly provided by Donald J. Zack (Wilmer Ophthalmological Institute, Johns Hopkins University, Baltimore, MD). This RPE cell line has been reported to have several characteristics of other normal RPE cells, such as an expression of Rpe65 and in vitro differentiation capacity. From the Departments of 1 Ophthalmology an

Stratified layer analysis reveals intrinsic leptin stimulates cryptal mesenchymal cells for controlling mucosal inflammation

Mesenchymal cells in the crypt play indispensable roles in the maintenance of intestinal epithelial homeostasis through their contribution to the preservation of stem cells. However, the acquisition properties of the production of stem cell niche factors by the mesenchymal cells have not been well elucidated, due to technical limitations regarding the isolation and subsequent molecular and cellular analyses of cryptal mesenchymal cells. To evaluate the function of mesenchymal cells located at the large intestinal crypt, we established a novel method through which cells are harvested according to the histologic layers of mouse colon, and we compared cellular properties between microenvironmental niches, the luminal mucosa and crypts. The gene expression pattern in the cryptal mesenchymal cells showed that receptors of the hormone/cytokine leptin were highly expressed, and we found a decrease in Wnt2b expression under conditions of leptin receptor deficiency, which also induced a delay in cryptal epithelial proliferation. Our novel stratified layer isolation strategies thus revealed new microenvironmental characteristics of colonic mesenchymal cells, including the intrinsic involvement of leptin in the control of mucosal homeostasis