167 research outputs found
Raman frequencies of graphitic carbon in Antarctic ureilites
Raman frequencies for the in-plane lattice vibration of graphite were surveyed for four Antarctic ureilites in order to construct a paradigm for structural properties of graphitic carbon in ureilites. Raman spectra were obtained by point-by-point measurements using a laser microbeam 1μm in diameter. The measured results formed an array in a two-dimensional plot between the E_ frequency and intensity ratio of two graphite-derived Raman bands. The graphitic matter in ALH-78019 gave the averaged E_ frequency at 1582.0 ⊿cm^, which agrees with the well-established wavenumber of the E_ in-plane lattice vibration of graphite. On the contrary, some graphitic matter in the ureilites (ALH-77257,Y-791538 and MET-78008) exhibited considerably up-shifted E_ frequency. Distribution in the array was proved to be closely linked to the extent of shock which the ureilites suffered
In-situ micro Raman studies on graphitic carbon in some Antarctic ureilites
The fine structures of graphitic materials contained in four Antarctic ureilites (ALH-77257,ALH-78019,MET-78008 and Y-791538) were investigated using a laser light (514.5nm), which could be focused onto a spot of 1μm in diameter. Raman spectra obtained differ not only among individual ureilite samples, but also among positions within a single carbonaceous vein of the same specimen. Moreover, one can classify the carbon into several groups on the basis of the spectra concerned. For all samples, both well-ordered graphitic carbon and semi-ordered graphitic carbon were observed. Amorphous carbon was detected in ALH-77257 and MET-78008. The difference in structural ordering among the samples is attributed to the difference in distribution of the components of carbonaceous material, indicating minor difference in genetic conditions or in locality within the parent body. Structural heterogeneity of carbon within a single carbonaceous vein implies the occurrence of two (or three) types of carbonaceous matters which have fairly different physicochemical properties and distinct histories. For the genesis of the carbonaceous matter in ureilites, a two-stage model is proposed assuming the graphite crystallization from metallic phase followed by the inflow of semi-ordered graphitic carbon or amorphous carbon into the well-ordered graphitic carbon produced from the metal
Spirulina Effectiveness Study on Child Malnutrition in Zambia
Ensuring adequate nutrition among vulnerable children has been a serious challenge in Zambia. Chronic child malnutrition is more predominant at 45 per cent while underweight and wasting are at 15 and 5 per cent respectively.
This study tested the effectiveness of spirulina on malnourished children in Zambia. The study took place from June 2012 to February 2013. Sixty children were divided into spirulina treatment and control groups. The outcome of taking spirulina was analysed by collecting anthropometric data. The fixed-effect regression result showed that 10g of spirulina dairy intake leads to improvement by producing 0.29 higher points in the height-for-age z-score (HAZ); confidence
interval (CI)[0.0404, 0.535]. On the contrary, the weight-for-age z-score (WAZ) and the mid-upper arm circumference z-score (MUACZ) did not show a significant difference, although treated children showed a larger improvement by 0.09 points and 0.38 points, respectively. This study implied the validity of spirulina in reducing chronic malnutrition
肺腺癌患者の予後予測におけるGAD1過剰発現の有用性
Background and Objectives: In a previous genome-wide screening, we identified hypermethylated CpG islands around glutamate decarboxylase 1 (GAD1) in lung adenocarcinoma (LADC). In this study, we aimed to investigate the methylation and expression status of GAD1 and its prognostic value in patients with LADC.
Methods: GAD1 methylation and mRNA expression status were analyzed using 33 tumorous and paired non-tumorous LADC samples and publicly available datasets. The prognostic value of GAD1 overexpression was investigated using publicly available datasets of mRNA levels and 162 cases of LADC by immunohistochemistry.
Results: The methylation and mRNA expression levels of GAD1, each having a positive correlation, were significantly higher in LADC tumors than in paired non-tumorous tissues. LADC patients with higher GAD1 mRNA expression showed significantly poorer prognosis for overall survival in publicly available datasets. Higher immunoreactivity of GAD1 was significantly associated with the pathological stage, pleural invasion, lymph vessel invasion, and poorer prognosis for cancer-specific and disease-free survival. Multivariate analysis revealed that GAD1 protein overexpression is an independent prognosticator for disease-free survival.
Conclusions: GAD1 mRNA and protein expression levels were significant prognostic factors in LADC, suggesting that they might be useful biomarkers to stratify patients with worse clinical outcome after resection
Studies of Raman scattering in novel disubstituted acetylene polymers
We have studied resonant and non-resonant Raman scattering spectra in thin films of novel disubstituted acetylene polymers such as poly(1-ethyl-2-phenylacetylene) (PEtPA), poly(1-n-hexyl-2-phenylacetylene) (PHxPA) and poly(1-phenyl- 2-p-n-butylphenylacetylene) (PDPA-nBu), which possess high photoluminescence (PL) quantum efficiency. We found that the Raman scattering frequency dispersion is smaller in disubstituted acetylene polymers than in other acetylene polymers, in agreement with many other strongly luminescent polymers. Assuming the model of short polyene conjugation length in these acetylene polymers, we can obtain the conjugation length (N) for each polymer from the respective phonon frequency of the carbon-carbon double bond; we obtained N equals 7 for PDPA-nBu, and N equals 5 or 6 for PHxPA and PEtPA. The related energies of 11Bu and 21Ag can be estimated from these N and are in good agreement with the respective absorption and PL spectra of the various disubstituted polymers.Optical Science, Engineering and Instrumentation '97, 1997, San Diego, CA, United StatesAkihiko Fujii, Maxim N. Shkunov, Z. Valy Vardeny, Kazuya Tada, Katsumi Yoshino, Masahiro Teraguchi, and Toshio Masuda "Studies of Raman scattering in novel disubstituted acetylene polymers", Proc. SPIE 3145, Optical Probes of Conjugated Polymers, (1 December 1997). DOI: https://doi.org/10.1117/12.29554
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