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Abstract: The Sn−Ti−Zn ternary phase diagram has been constructed using the CALPHAD technique. The Ti−Zn binary system phase boundaries were determined using differential scanning calorimetry and the solid-liquid diffusion couples method. In addition, the formation energy of some stoichiometric compounds was obtained using first-principle band energy calculations. For the ternary system, some alloys were prepared by equilibration at 600 or 700 °C, and the compositions of the precipitates were analyzed using electron probe microanalysis. Thermodynamic assessment of the Ti−Zn and Sn−Ti−Zn systems was performed based on the experimental information and by adopting reported values of the thermodynamic properties of the Sn−Zn and Sn−Ti binary systems. Microstructural observation showed that Sn3Ti5Zn12 exists in the ternary system. Seven types of invariant reaction on the Sn-rich liquidus surface of the ternary system are predicted by the phase diagram calculations. The ternary eutectic point falls at 0,0009 mass% Ti and 8.69 mass% Zn, at T=192.40°C, which is slightly lower than the calculated eutectic point of Sn−Zn binary alloy (T=192.41°C). Based on these results, a nonequilibrium solidification process using the Scheil model was simulated.

Abstract: Eleven mutant lines exhibiting decreased numbers of chloroplasts per cell were isolated from 8 800 tagged mutant lines of Physcomitrella patensby microscopic observations. Chloronema subapical cells in wild‐type plants had a mean of 48 chloroplasts, whereas chloroplast numbers in subapical cells in mutant lines 215and 222decreased to 75 % of that in the wild type. Seven mutant lines ‐ 473, 122, 221, 129, 492, 207,and 138‐ had about half as many chloroplasts as the wild type. Mutant line 11had a few remarkably enlarged chloroplasts, and mutant line 347had chloroplasts of various sizes. Whereas the cell volume was the same as in the wild type in mutant lines 222, 473, 221, 129, 492,and 207,the cell volume of the other mutants increased. The chloroplast number of leaf cells was the same as that of chloronema cells in each mutant line when gametophores could be formed. Treatment with ampicillin decreased the number of chloroplasts in all mutant lines. Southern hybridization using DNA in tags as probes showed that only one insertion occurred in mutant lines 473and 221.To determine whether the tagged DNA inserted into the known genes for plastid division, we isolated the PpMinD1, PpMinD2,and PpMinE1genes. Genomic polymerase chain reaction analysis showed that the PpFtsZand PpMinD/Egenes were not disrupted by the insertion of the tags in mutant lines 11and 347,respectively.

Abstract: In order to specify phylogenetic positions of the genera of Tofieldiaceae (Tofieldia, Triantha, Pleea, Harperocallis, Isidrogalvia),and to suggest reasonable circumscription of the family and genera of Tofieldiaceae, we determined DNA sequences of matK and rbcL for each genus of the family, and analyzed them phylogenetically with the 45 families and 113 genera of the monocots other than Tofieldiaceae, whose matK and rbcL sequences have already been reported. We found that Tofieldia, Triantha, Pleea,and Harperocallisform the same clade, which receives 100 % bootstrap support. This clade can be regarded as corresponding to Tofieldiaceae, and is embedded in the clade of Alismatales (98 %). On the other hand, Isidrogalviais not included in this Tofieldiaceae clade, and positioned as sister to Narthecium(100 %), embedded in the clade of Nartheciaceae (Dioscoreales) (100 %). In the Tofieldiaceae, Pleeafirst diverges from the remaining three genera (100 %), and then, Harperocallisdiverges from the Tofieldia‐Trianthacomplex (100 %). In the Tofieldia‐Trianthacomplex, five Tofieldiaspecies form the same clade (100 %), and two Trianthaspecies form another clade (100 %). Thus, Isidrogalviashould be transferred from Tofieldiaceae to Nartheciaceae. As Isidrogalvia,as well as the Nartheciaceae, have the carpels that are fully connate into a single style, Isidrogalviafits the Nartheciaceae well with respect to carpel connation. After this transfer, the Tofieldiaceae correspond mainly to plants with almost free carpels and three styles. Pleeais better treated as an independent genus than included in Tofieldia. Trianthacan be treated either as an independent genus or as congeneric with Tofieldia.

Abstract Three subfamilies of the En/Spm-type transposable element of carrot, Tdc A, B, and C, were characterized. It was supposed that the Tdc A subfamily may include autonomous elements which can produce transposases. Tdc B elements are defective, but still generate transcripts containing mutant open reading frame (ORF) sequences for transposases. The single member of the Tdc C group recovered seems to be a pseudogene. The sequences of the transposase ORFs of Tdc A and Tdc B elements are more highly conserved than those of the 5´ and 3´ untranslated regions and introns, as is found in other structural genes that are subject to selection. These observations indicate that the mutations in the nucleotide sequences of the Tdc elements occurred in the host genome. However, the mutations in the 5´ and 3´ untranslated regions and introns, which may not be sufficient to prevent transposition, accumulated in autonomous elements, which could transpose and produce copies. When the reproduction rate and the rate of disabling mutations reached an equilibrium, that is, when the birth rate of the transposable elements in the genome equalled the death rate, the population of elements achieved a stationary state in the genome, and could thus survive.

Abstract: A thermodynamic analysis of the phase equilibria in the Ni-Si-B ternary system was conducted. A regular solution approximation based on a sublattice model was adopted to describe the Gibbs energies for the individual phases in the binary and ternary systems. A set of thermodynamic parameters for the individual phases was evaluated from literature data on phase boundaries and thermochemical properties. The optimized parameters reproduced the experimental data, for the most part, satisfactorily. However, in the calculated isothemal section at 850 °C, phase equilibria between the fcc phase and Ni6Si2B or Ni3Si(β 1) and Ni6Si2B were found instead of the experimentally observed equilibria between Ni3Si(β 1) and Ni3B or Ni5Si2(γ) and Ni3B. Further, in the primary crystal surface for the fcc phase, the calculated liquidus temperatures were higher than the reported values by approximately 80 °C. Therefore, it is considered that the fcc phase evaluated in the Ni-Si system by Lindhólm and Sundman is too stable.

Abstract: Thermodynamic constraints are introduced to describe Gibbs energies for a CALPHAd-type calculation; available data on the pure elements and phase diagram data were used to optimize relevant parameters. Constraints can be applied to the mathematical description of Gibbs energies for three regions of phase diagrams: those with complete miscibility, those with an intermetallic compound, and those with a miscibility gap. The authors examine the present thermodynamic constraints in construction of Gibbs energies for the Ag-Pd, Mg-Sn, and Au-Ni binary systems as typical examples for these cases. The optimization procedure for obtaining parameters for models of the Gibbs energies is divided mainly into four steps to reach the final parameters, and the results obtained in each step are compared in detail. The authors also present assessed parameters for the Gibbs energies concerning these three binary systems by the available thermodynamic data in addition to the phase diagram data with the present thermodynamic constraints.

It is well known that nickel is a beneficial alloying element in copper bearing steels as it prevents hot shortness. On the other hand, the addition of tin promotes hot shortness. Though some mechanisms for promoting these phenomena have been suggested, a quantitative discussion has still failed to establish the cause. In the present study, changes in the composition in the vicinity of the scale/metal interface owing to high temperature oxidation were experimentally determined using pure irons with copper, nickel, and tin additions. The experimental findings, such as the fraction of liquid phase and the change in composition in the progress of scale formation, were then explained by thermodynamic considerations using the Fe–Cu–Ni and Fe–Cu–Sn phase diagrams calculated from a computerised thermodynamic database. The thermodynamic considerations were also applied to a quantitative discussion on hot shortness and some measures for preventing hot shortness of copper bearing steels were suggested.

AbstractHasebe, M., Soh, T., Hattori, M. and Fujihara, N. 1998. An attempt to produce transgenic chicken mediating sperm cells as vectors. J. Appl. Anim. Res., 14: 143–150.An attempt was made to produce possible transgenic chicken via sperm cells as vectors. In vitroincubation of ejaculated chicken spermatozoa with exogenous gene (MiwZ DNA) showed a possibility of the incorporation of foreign gene into sperm cells, which was examined by the PCR analysis. The embryos obtained from the eggs inseminated with DNA-treated spermatozoa indicated an existence of transferred exogenous gene in the blastodermal cells of the incubated fertile eggs. Exogenous gene injected into rooster testes was neither detected in the sperm cells nor in the blastodermal cells of fertilized eggs, which were inseminated with spermatozoa obtained from the testes-injected rooster. Sperm head, tail and cell membrane separated from DNA-treated spermatozoa revealed to contain foreign DNA, suggesting a possibility of incorporation of exogenous gene into plasma membrane from treated-spermatozoa.

The melt surface temperature in Czochralski silicon growth was studied by CCD camera observation. The thermal radiation energy from the melt surface was converted into temperature by the blackbody calibration method and was recorded with a VCR as two-dimensional color images. The experimental results without a crystal revealed that the temperature distribution at the melt surface can change in four patterns depending on the crucible rotation rate: axisymmetric spoke pattern at low rotation rates, n-folded and island patterns at medium rotation rates, and cellular patterns at high rotation rates. To predict the fluid motion from the experimental observations, three-dimensional time-dependent numerical simulations of the silicon melt flow were executed. As a result, a qualitative transition model for the temperature distribution and the Czochralski silicon melt flow was derived.

Summary: The Fe-based binary phase diagram system was explained as an example of a personal database for phase diagrams. The present paper offers a general description for creating a private phase diagram database. The authors hope that the example database will be made better and used widely. Because the “Fe Binary Diagrams” database was copied with the cooperation of Dr. H. Enoki, Tohoku University, on the anonymous ftp (ftp.material.tohoku.ac.jp, ip address: 130.34.66.36), anyone can obtain it freely.

Electrophysiological methods were applied to 160 healthy adult male guinea pigs in order to investigate the effects of pure-tone exposure for 24 h on the inner ear. A reduction in cochlear microphonics (CM), action potential (AP) and endocochlear potential was observed following exposure to 110 dB at 100 Hz, 100 dB at 200 and 600 Hz and 95 dB at 2 kHz. The observed K+ endolymphatic concentration during 40 min anoxia remained unchanged. In contrast K+ decreased in control animals and following exposure to pure tones varying from 110 dB at 60 Hz to 85 dB at 2 kHz. These findings indicate that high frequency tones have a greater effect on inner ear functions than those of lower frequency, decreasing the maximum output voltage of CM and AP but not changing K+ endolymphatic concentration.

The damping capacity and mechanical properties of ferromagnetic porous sintered specimens having a composition within the range iron plus 0–16%Cr and 0–4%Mo have been examined. Damping capacity and the mechanism of damping are discussed with respect to the effect of porosity and the stress concentration around each pore under the influence of an applied vibrational stress. Maximum damping capacity was obtained with a composition of Fe–16Cr–2%Mo, vacuum-sintered at 1200°C for 120 min at a pressure of 2·66 Pa (2 × 10−5torr).

The Fe-based binary phase diagram system was explained as an example of a personal database for phase diagrams. The present paper offers a general description for creating a private phase diagram database. The authors hope that the example database will be made better and used widely. Because the “Fe Binary Diagrams” database was copied with the cooperation of Dr. H. Enoki, Tohoku University, on the anonymous ftp (ftp.material.tohoku.ac.jp, ip address: 130.34.66.36), anyone can obtain it freely.

The solubility of carbon in bcc Fe and fcc Co-Ni alloys has been examined by the diffusion couple method, and a thermodynamic analysis of the data has been carried out, taking into account the effect of magnetic transition. It has been detected that the solubility slightly deviates from the ordinary linear relation between log [pct C] and 1/T below the Curie point. The deviation has been well explained by the magnetic effect on the Gibbs energy for the bcc Fe-C and fcc Co-Ni-C phases.

The relations between the thermodynamic properties of the unary lattice gas and the equivalent binary substitutional and interstitial alloys are discussed. New methods for the estimation of the partial particle energy in a lattice gas from Monte Carlo simulations in both the petit and grand canonical ensembles are presented and evaluated. Taken together with well established procedures for estimating the particle chemical potential and more recent procedures for estimating the lattice gas pressure, it becomes possible, for the first time, to obtain reliable determinations of both the partial and integral quantities for internal energy, entropy and free energy at a given temperature and composition in a rigid binary alloy from the one Monte Carlo experiment in either ensemble. Some illustrative results are given for the square lattice with nearest neighbour interactions.

The chloroplast genome of most land plants is highly conserved. In contrast, physical and gene mapping studies have revealed a highly rearranged chloroplast genome in species representing four families of ferns. In all four, there has been a rare duplication of the psbA gene and the order of the psbA, 16S, and 23S rRNA genes has been inverted. Our analysis shows that the described rearrangement results from a minimum of two inversions within the inverted repeat. This chloroplast DNA structure provides unambiguous evidence that phylogenetically links families of ferns once thought to belong to different major evolutionary lineages.

Pteriodophytes have a longer evolutionary history than any other vascular land plant and, therefore, have endured greater loss of phylogenetically informative information. This factor has resulted in substantial disagreements in evaluating characters and, thus, controversy in establishing a stable classification. To compare competing classifications, we obtained DNA sequences of a chloroplast gene. The sequence of 1206 nt of the large subunit of the ribulose-bisphosphate carboxylase gene (rbcL) was determined from 58 species, representing almost all families of leptosporangiate ferns. Phlogenetic trees were inferred by the neighbor-joining and the parsimony methods. The two methods produced almost identical phylogenetic trees that provided insights concerning major general evolutionary trends in the leptosporangiate ferns. Interesting findings were as follows: (i) two morphologically distinct heterosporous water ferns, Marsilea and Salvinia, are sister genera; (ii) the tree ferns (Cyatheaceae, Dicksoniaceae, and Metaxyaceae) are monophyletic; and (iii) polypodioids are distantly related to the gleichenioids in spite of the similarity of their exindusiate soral morphology and are close to the higher indusiate ferns. In addition, the affinities of several "problematic genera" were assessed.

Irradiation of 2‐thiouracil (I), in the presence of the olefins (II), yields a mixture of the 2‐substituted pyrimidones (III), the insertion and addition products (IV), and/or the (2 + 2)cycloadducts (V).

Irradiation through a Pyrex filter of mixtures of the pyridazinone (I) and the olefins (II) gives the (2 + 2)cycloaddition products (III).

The photoreductive decarboxylation of various carboxylic acids is performed via photolysis of their benzophenone oxime esters (III) as outlined in the reaction scheme.

The thiones (Ia) and (Ib) undergo photoaddition to the olefins (II) and (IV) to give the products shown in the scheme.

Bei der Bestrahlung der Pyridazinthione (I) in Gegenwart der Olefine (II) entstehen neben den Thienopyridazinen (III) auch die Disulfide (IV).