TURING INSTABILITY IN THE OREGONATOR MODEL(Session IV : Structures & Patterns, The 1st Tohwa University International Meeting on Statistical Physics Theories, Experiments and Computer Simulations)

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Energetics of the distribution of cell wall in wood based on an eigenvalue analysis

Wood is a highly heterogeneous material characterized by a number of properties that vary significantly among samples. Even in woods of the same density, substantial differences in properties show up depending on the distribution pattern of their cell walls. With the aim of deep understanding of the wood variation, we examine this pattern from the physical perspectives using samples of the same density but with significantly different shrinkages. The power spectrum, which represents the regularity of the occurrence of cell walls or lumen, was obtained through Fourier transform processing of micrographs of the transverse sections of wood samples. The set of eigenvalues calculated from the variance–covariance matrix comprising the spectra is identified with a Hamiltonian representing the energy eigenstate of the wood. The cell wall distribution can then be analyzed from within thermodynamics and statistical mechanics. The eigenvalues from the images of latewood were widely distributed compared with those from earlywood. The first eigenvalue is equivalent to the Helmholtz free energy, and thus the high-shrinkage samples showed large Helmholtz free energy because of the high presence of latewood. The Shannon entropy calculated from the probability associated with each energy eigenstate was larger in images of earlywood than latewood. That is, low-shrinkage samples have a more homogeneous structure than high-shrinkage samples. These results were strongly consistent with observations from micrographs and previous knowledge of the physical properties of woods. The physical approaches proposed in this study is independent of the origin of the data and therefore has a wide application

Functional assays for mRNA detect many new messages after male meiosis in mice

We have investigated the changes occurring in the pattern of translatable mRNA species in germ cells during spermatogenesis of mice. Highly homogeneous cell populations of spermatocytes or spermatids were purified. Poly(A)+ mRNA was isolated from each cell population by oligo(dT)-cellulose chromatography. A comparison of meiotic and post-meiotic mRNAs was made by two-dimensional gel analyses of their in vitro synthesized translation products. Among spots identified in the fluorograms of two-dimensional gels, a number of qualitatively new proteins appeared after meiosis. The results suggest that some of poly(A)+ mRNAs are transcribed post-meiotically in haploid germ cells.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/23827/1/0000066.pd

Thermodynamic assessment of Fe–Ti–S ternary phase diagram

A thermodynamic analysis of the Fe-Ti-S ternary system was performed by incorporating first-principles calculations into the calculation of phase diagrams (CALPHAD) method. To evaluate the Gibbs energy, the Debye-Grüneisen model was applied for some sulfides of the Ti-S binary system. In addition, the cluster expansion and cluster variation methods were used for the solid solution phases in the Ti-S binary and (Fe,Ti)S phases. The calculated Ti-S binary phase diagram showed good agreement with the experimental results. The very low solubility of the Ti solid solution in the Ti-S system, as reported by Murray, agreed well with our calculated results. A binodal phase decomposition of the liquid phase was expected in the S-rich region. The Gibbs energy curve of (Fe,Ti)S between FeS and TiS was found to be convex downward. This is characteristic of an isomorphic solid solution, attributed to the attractive interaction between Fe and Ti in (Fe,Ti)S. The vertical phase diagram between FeS and TiS, obtained using the thermodynamic database, was in good agreement with the experimental results of Mitsui et al. The solubility products of (Fe,Ti)S have been experimentally estimated previously. The calculated solubility product agreed with the experimental value of TiS

Aldehyde Dehydrogenase Activity as a Marker of Quality in Cryopreserved Cord Blood

We investigated the effects of cryopreservation on CD34+ cells and aldehyde dehydrogenase (ALDH) -positive cells (ALDH (+) cells) in the umbilical cord blood (UCB) of unrelated donors. Ten units of UCB were collected at the Kanagawa Cord Blood Bank from September 2009 to November 2010. These UCB units were frozen for 2 weeks or 1 year, and then assayed for quality by flow cytometry analysis and colony-forming assay. We found that both ALDH (+) cells and the numbers of total colony-forming units and colony-forming units of granulocyte/macrophage from the isolated CD34+ cells were significantly decreased after all cryopreservation. The numbers of ALDH (+) /CD34+ cells, ALDH (+) /CD34+CD38- cells, and total colony-forming units from the cryopreserved UCB units continued to decrease over time with cryopreservation. In contrast, levels of traditional primitive surface markers were not significantly decreased in CD34+ cells and CD34+CD38- cells after cryopreservation, although this result depended on the duration of cryopreservation. These findings suggested that ALDH (+) cells could be a new marker for assessing cryopreserved UCB quality prior to hematopoietic cell transplantation

Seminolipid and its precursor/degradative product, galactosylalkylacylglycerol, in the testis of saposin A- and prosaposin-deficient mice

Sphingolipid activator proteins (saposins A, B, C, and D) are derived from a common precursor protein (prosaposin) and specifically activate in vivo degradation of glycolipids with short carbohydrate chains. A mouse model of prosaposin deficiency (prosaposi

A sporadic case of CTLA4 haploinsufficiency manifesting as Epstein–Barr virus-positive diffuse large B-cell lymphoma

Cytotoxic T-lymphocyte-associated antigen 4 (CTLA4) is a coinhibitory receptor that plays an essential role in maintaining immune system homeostasis by suppressing T-cell activation. We report a sporadic case of CTLA4 haploinsufficiency in a patient with Epstein-Barr virus-positive diffuse large B-cell lymphoma and subsequent benign lymphadenopathy. A missense mutation in exon 2 of the CTLA4 gene (c.251T>C, p.V84A) was found in the patient's peripheral blood and buccal cell DNA, but not in her parents' DNA. CTLA4 expression decreased in the peripheral regulatory T cells upon stimulation, whereas CTLA4 and PD-1-positive T cell subsets increased, possibly to compensate for the defective CTLA4 function. This case suggests that some adult lymphoma patients with no remarkable medical history have primary immune disorder. As immune-targeted therapies are now widely used for the treatment of malignancies, it is increasingly important to recognize the underlying primary immune disorders to properly manage the disease and avoid unexpected complications of immunotherapies

A genomic clone of Zfy-1 from a YDOM mouse strain detects post-meiotic gene expression of Zfy in testes

In order to obtain a genomic clone of Zfy-1 from a Y chromosome of (YDOM) origin, we cloned size-fractionated SJL/J DNA in EMBL-4 and selected colonies which hybridized to pDP1007, a human zinc finger Y clone. The specificity of the clone in hybridizations to mouse and human DNA and partial sequencing confirmed that the clone (subcloned as pGZfy1D) was of Zfy-1 origin. Studies on the expression during testicular development of mRNAs hybridizing to the clone suggested that the gene is expressed post-meiotically.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/27626/1/0000001.pd