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Heparin-binding EGF-like growth factor (HB-EGF) is first synthesized as a membrane-anchored form (proHB-EGF), and its soluble form (sHB-EGF) is released by ectodomain shedding from proHB-EGF. To examine the significance of proHB-EGF processing in vivo, we generated mutant mice by targeted gene replacement, expressing either an uncleavable form ([HB.sup.uc]) or a transmembrane domain-truncated form ([HB.sup.[DELTA]tm]) of the molecule. [HB.sup.uc/uc] mice developed severe heart failure and enlarged heart valves, phenotypes similar to those in proHB-EGF null mice. On the other hand, mice carrying [HB.sup.[DELTA]tm] exhibited severe hyperplasia in both skin and heart. These results indicate that ectodomain shedding of proHB-EGF is essential for HB-EGF function in vivo, and that this process requires strict control.

Research has been conducted on histone H3 lysine 9 methylation. Results indicate the decrease of this methylation in mammalian histone methyltransferase-deficient mice and embryonic stem cells.

Previous analysis employing chimeric and transgenic rescue experiments has suggested that Otx2 is required in the neuroectoderm for development of the forebrain region. In order to elucidate the precise role of Otx2 in forebrain development, we attempted to generate an allelic series of Otx2 mutations by Flp- and Cre-mediated recombination for the production of conditional knock-out mice. Unexpectedly, the neo-cassette insertion created a hypomorphic Otx2 allele; consequently, the phenotype of compound mutant embryos carrying both a hypomorphic and a null allele ([Otx2.sup.frt-neo/-]) was analyzed. [Otx2.sup.frt-neo/-] mutant mice died at birth, displaying rostral head malformations. Molecular marker analysis demonstrated that [Otx2.sup.frt-neo/-] mutant embryos appeared to undergo anterior-posterior axis generation and induction of anterior neuroectoderm normally; however, these mutants subsequently failed to correctly specify the forebrain region. As the rostral margin of the neural plate, termed the anterior neural ridge (ANR), plays crucial roles with respect to neural plate specification, we examined expression of molecular markers for the ANR and the neural plate; moreover, neural plate explant studies were performed. Analyses revealed that telencephalic gene expression did not occur in mutant embryos due to defects of the neural plate; however, the mutant ANR bore normal induction activity on gene expression. These results further suggest that Otx2 dosage may be crucial in the neural plate with respect to response to inductive signals primarily from the ANR for forebrain specification. Key Words: forebrain; neural plate; anterior neural ridge; regionalization; hypomorphic allele; Otx2.

Joints for 500-kV XLPE cable are now under development in Japan to enable the long-distance transmission of high-capacity power to urban areas. Basic research was carried out from 1989 to 1992 that determined joint type and design values. This paper reports on the electric performance of the fabricated joints. Various tests were conducted to evaluate the performance and the design values. As a results of this evaluation it was found that it was possible to realize joints for 500-kV XLPE cable. Field tests will be conducted as the final stage to confirm the long-term performance of the system.

Mutant mice embryos in which the focal adhesion kinase (FAK), a protein tyrosine kinase, is absent show poor development of mesoderm because of retarded motility of cells. The anteroposterior axis, notochord and somite are not formed while the head mesenchyme becomes involuted. However, formation of the head, lateral, and extra-embryonic mesenchyme remains normal. The absence of FAK also increases the formation of focal adhesions which causes rise in tyrosine phosphorylation in many proteins.

The c-mos proto-oncogene product (Mos) is vital for the inhibition of the second meiotic metaphase in mice and for the oocyte maturation mechanism in Xenopus. Mos inhibits parthenogenetic stimulation in Xenopus, explains oogenetic and teratogenic processes in mammals and infertility in women. Mos is not essential for the induction of oocyte maturation, spermatogenesis or somatic cell cycle in mice.

We demonstrated the emission of multicolored light from a powder electroluminescent device using a thermochromic material through temperature control. At 20°C, the emission of a sapphire blue light was observed. Upon increasing the temperature, the color of the thermochromic materials changed, leading to sky‐blue emission. [ABSTRACT FROM AUTHOR]

GLP and G9a-related methyltransferases are the mammalian histone H3 Lys 9 (H3-K9) methyltransferase that targets euchromatic regions and is essential for murine embryogenesis. The findings carried out on the GLP and G9a shows that both exert H3-K9 methyltransferase function in vivo, by the formation of higher-order heteromeric complexes.

Secondary inorganic aerosols, including sulfate, nitrate, and ammonium contribute to a large extent to the severe haze pollution events in China. Understanding their formation mechanisms is critical for designing effective mitigation strategies to control haze pollution, especially as the role of nitrate seemed to become more important recently, especially in some megacities. In the present study, simultaneous observations were conducted in two megacities (Chengdu and Chongqing) in Sichuan Basin of southwest China, one of the regions suffering from severe aerosol pollution. One typical long-lasting pollution event in Chengdu and Chongqing was captured during wintertime from December 25, 2016 to January 5, 2017. The campaign-average of hourly concentrations of PM 2.5 , sulfate, and nitrate, measured by an Aerosol Analyzer (ZSF) were 101 ± 73.8 μg/m3, 15.9 ± 11.8 μg/m3, and 24.9 ± 20.6 μg/m3, respectively, in Chengdu, and were 87.7 ± 53.8 μg/m3, 19.7 ± 13.5 μg/m3, and 15.1 ± 10.1 μg/m3, respectively, in Chongqing. Nitrate contributed substantially to PM 2.5 pollution when PM 2.5 was lower than 150 μg/m3, largely due to the strong secondary transformation of NO X to nitrate during the occurrence of the pollution episode. Heterogeneous hydrolysis of N 2 O 5 dominated nitrate formation during nighttime, while photochemical reactions and high-RH enhanced gas- to aqueous-phase dissolution of NH 3 and HNO 3 or cloud processes likely played important roles for nitrate formation during daytime. RH-dependent heterogeneous reactions contributed greatly to the formation of sulfate. NO X is confirmed to play an important role as an oxidant in accelerating the secondary transformation of SO 2 to sulfate at high RH and low O 3 levels under neutralization condition during heavy PM 2.5 pollution episode. Results from this study identified the formation mechanism of nitrate, especially during the daytime, and addressed the importance of heterogeneous inorganic reactions in the formation of heavy aerosol pollution events. Image 1 • Nitrate rather than sulfate largely drove the growth of PM 2.5 pollution in Sichuan Basin. • Photochemical oxidation had stronger influence on the formation of nitrate than sulfate. • NO X promoted the secondary transformation of SO 2 to sulfate during heavy PM 2.5 pollution episode. Nitrate rather than sulfate largely drove the growth of PM 2.5 pollution, due to the strong atmospheric photochemistry in daytime and high RH sustained nitrate growth at night. [ABSTRACT FROM AUTHOR]

The development of the mammalian antero-posterior (A-P) axis is proposed to be established by distinct anterior and posterior signaling centers, anterior visceral endoderm and primitive streak, respectively. Knock-out studies in mice have shown that Otx2 and Cripto have crucial roles in the generation and/or functions of these anterior and posterior centers, respectively. In both Otx2 and Cripto single mutants, the initial formation of the A-P axis takes place in a proximal-distal (P-D) orientation, but subsequent axis rotation fails to occur. To examine the developmental consequences of the lack of these two genes, we have analyzed the [Otx2.sup.-/-];[Cripto.sup.-/-] double homozygous mutant phenotype. In the double mutants, the expression of the A-P axis markers Cer-1, Lim1, and Wnt3 was not induced, while expression of Fgf8 and T was expanded throughout the epiblast, indicating that the double mutants could not form the A-P axis even in its initial P-D orientation. In addition, the double mutants displayed defects in differentiation of the visceral endoderm overlying the epiblast, as well as in the extraembryonic ectoderm. Furthermore, differentiation of neuroectoderm was accelerated as judged by the reduction of Oct4 expression and emergence of Sox1 and Gbx2 expression in the double mutant epiblast. The resulting ectoderm only displayed characteristics of anterior hindbrain, implicating it as a ground state in the mammalian body plan. Our results indicate that complementary functions of Otx2 and Cripto are essential for initial patterning of the A-P axis in the mouse embryo. Key Words: Otx2; Cripto; A-P axis generation; anterior hindbrain; Gbx2; Oct4; organizing center.