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Heparin-binding epidermal growth factor (EGF)-like growth factor (HBEGF) is a ligand for the EGF receptor (EGFR), one of the most commonly amplified receptor tyrosine kinases (RTKs) in glioblastoma (GBM). While HBEGF has been found to be expressed in a subset of malignant gliomas, its sufficiency for glioma initiation has not been evaluated. In this study, we demonstrate that HBEGF can initiate GBM in mice in the context of Ink4a/Arfand Ptenloss, and that these tumors are similar to the classical GBM subtype observed in patients. Isogenic astrocytes from these mice showed activation not only of Egfr but also the RTK Axl in response to HBEGF stimulation. Deletion of either Egfr or Axl decreased the tumorigenic properties of HBEGF-transformed cells; however, only EGFR was able to rescue the phenotype in cells lacking both RTKs indicating that Egfr is required for activation of Axl in this context. Silencing of HBEGF in vivoresulted in tumor regression and significantly increased survival, suggesting that HBEGF may be a clinically relevant target.

The use of a series of flexible, linear diquaternary alkylammonium ions (CnH2n+1)2HN⁺(CH2)5N⁺H(CnH2n+1)2 with n = 1−5 as structure-directing agents in zeolite syntheses is described. Among the ammonium ions studied here, the (CH3)2HN⁺(CH2)5N⁺H(CH3)2 and [(CH3)2CH]2HN⁺(CH2)5N⁺H[CH(CH3)2]2 ions were found to be new structure-directing agents for the crystallization of levyne and MCM-22, respectively. The overall synthesis results of this study reveal that the phase selectivity of the crystallization can differ according to both the length of the dialkyl substituents on the ammonium ion and the oxide composition of synthesis mixtures. The host−guest interactions in nonasil, ZSM-12, mordenite, and levyne containing (CH3)2HN⁺(CH2)5N⁺H(CH3)2 as a guest molecule are investigated by ¹H−¹³C CP MAS NMR and Raman spectroscopies, and computer modeling studies, and it is shown that the organic guest molecules adopt distinct conformations in order to fit in the pores of each zeolite host.

The ¹H-¹³C CP MAS NMR and Raman spectra of N,N,N,N‘,N‘,N‘-hexaethylpentanediammonium (Et6-diquat-5) ions encapsulated within P1, SUZ-4, and ZSM-57 zeolites are presented. The Et6-diquat-5 molecules occluded are found to adopt distinct molecular conformations in order to fit in the pores of each zeolite host. Computer modeling studies show that encapsulation of Et6-diquat-5 in the small-pore zeolite P1 is not energetically favorable. However, a remarkable match between the conformation of guest molecule and the geometry of the host structure is observed for the medium-pore zeolites SUZ-4 and ZSM-57, revealing the existence of organic structure-directing effect. The overall results of this study suggest that conformations available to the flexible, linear organic cation like Et6-diquat-5 may differ considerably according to the type and concentration of alkali cations present in the zeolite synthesis mixture, which is a critical factor affecting the phase selectivity of the crystallization. It thus appears that the modification of conformations of flexible organic structure-directing agents by varying the type and concentration of alkali cations may be an area of considerable possibility for finding new zeolite structures.

Abstract:  In order to calculate the buckling load of a rectangular plate, the analytical approach is used in this study. The plate is assumed to be simply supported on four edges and loaded by uniform stresses along the edges. If the plate is slender, the buckling is elastic. However, if the plate is sturdy, it buckles in the plastic range. Then, the instantaneous moduli in the constitutive equations depend on the external loading. In this study, the elastic and plastic buckling equations are derived for rectangular plates under biaxial loading, and the corresponding interaction curves are presented. The influences of aspect ratios, load ratios and hardening factors on the buckling stresses are investigated for rectangular plates. From the plastic buckling analysis, the optimal combination of loads is given for the buckling strength.

In order to calculate the buckling load of a rectangular plate, the analytical approach is used in this study. The plate is assumed to be simply supported on four edges and loaded by uniform stresses along the edges. If the plate is slender, the buckling is elastic. However, if the plate is sturdy, it buckles in the plastic range. Then, the instantaneous moduli in the constitutive equations depend on the external loading.

We have fabricated Pt/SBT/insulator/Si structure for the transistor gate in MFIS‐FET and investigated the electrical properties of MFIS structure with various insulator materials. SrBi2Ta2O9films as a ferroelectric layer were deposited by metal organic decomposition (MOD) technique, on various insulator structures including SiON, and Al2O3as well as on Pt/Ti/SiO2/Si structures. The effect of annealing temperature on the electrical properties of MFIS structures was investigated in order to analyze the applicability to conventional CMOS process. Although the remnant polarization of SBT films for MFM structure was increased with increasing annealing temperature, the memory window which has a relationship with remnant polarization of ferroelectrics was differently displayed with insulator structure in MFIS structure.

The performance of an Allan variance measuring system was drastically improved by employing time interval analysis incorporating a beat frequency method. It was used to evaluate the performance of a heterodyne optical phase-locked loop with a very low optical frequency tracking error of 0.4mHz at the integration time of 70s. Advantages of the system are precise measurement for highly stable frequency sources with good reproducibility and simple structure.

Abstract: Allele und genotype frequencies and the mutation rate of a short tandem repeat locus, the myelin basic protein (MBP) gene, were studied in 973 unrelated Koreans. The alleles were distributed in two discrete regions, one in a high molecular weight region (A) above 190 bp and the other in a low molecular weight region (B) below 150 bp. In a heterozygote, two alleles were found in each region. In region A 13 alleles were found and in region B 7 alleles. Most alleles showed a difference of 4 bp, but three interalleles were found in region A. Allele frequencies in Koreans differed from those reported for Germans and Portuguese. Sets of alleles, one from each region, were linked and transmitted to the offspring. A total of 36 haplotypes and 148 genotypes was identified. In 763 gametes of 550 families, whose parent-child relationship was confirmed using other serological and DNA systems, all alleles were transmitted in a Mendelian fashion, and no mutations were observed. The polymorphism information content (PIC) in Koreans was calculated as 0.833 for region A and 0.718 for region B. The power of discrimination (PD) was 0.959 for region A and 0.901 for region B. No significant deviation from Hardy-Weinberg equilibrium could be observed for this system.

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