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Asymptotic solvers for ordinary differential equations with multiple frequencies

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Science China Mathematics 2015年第11期58卷 2279-2300页

作者： CONDON Marissa deaO Alfredo GAO Jing ISERLES Arieh School of Electronic Engineering Dublin City University Departmento de Matematicas Universidad Carlos III de Madrid School of Mathematics and Statistics Xi'an Jiaotong University DAMTP Centre for Mathematical SciencesUniversity of Cambridge

We construct asymptotic expansions for ordinary differential equations with highly oscillatory forcing terms,focusing on the case of multiple,non-commensurate *** derive an asymptotic expansion in inverse powers of the oscillatory parameter and use its truncation as an exceedingly effective means to discretize the differential equation in *** examples illustrate the effectiveness of the method.

关键词： highly oscillatory problems ordinary differential equation modulated Fourier expansions multiple frequencies numerical analysis

Disruption of Cortical Microtubules by Overexpression of Green Fluorescent Protein-Tagged a-Tubulin 6 Causes a Marked Reduction in Cell Wall Synthesis

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Journal of Integrative Plant Biology 2006年第1期48卷 85-98页

作者： David h. Burk Ruiqin Zhong W. herbert Morrison iii Zheng-hua Ye Department of Plant Biology University of Georgia Athens Georgia 30602 USA Richard B. Russell Agriculture Research Center U.S. Department of Agriculture Agricultural Research Service Athens Georgia 30604 USA

It has been known that the transverse orientation of cortical microtubules （MTs） along the elongation axis is essential for normal cell morphogenesis, but whether cortical MTs are essential for normal cell wall synthesis is still not clear. In the present study, we have investigated whether cortical MTs affect cell wall synthesis by direct alteration of the cortical MT organization in Arabidopsis thaliana. Disruption of the cortical MT organization by expression of an excess amount of green fluorescent protein-tagged a-tubulin 6 （GFP-TUA6） in transgenic Arabidopsis plants was found to cause a marked reduction in cell wall thickness and a de- crease in the cell wall sugars glucose and xylose. Concomitantly, the stem strength of the GFP-TUA6 overexpressors was markedly reduced compared with the wild type. In addition, expression of excess GFP- TUA6 results in an alteration in cell morphogenesis and a severe effect on plant growth and development. Together, these results suggest that the proper organization of cortical MTs is essential for the normal synthesis of plant cell walls.

关键词： Arabidopsis thaliana cell elongation cell wall synthesis cortical microtubules microtubule organization.

hafnium carbide structural foams synthesized from polymer precursors

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中国有色金属学会会刊：英文版 2006年第A02期16卷 85-88页

作者： FAN hai-bo YANG hong N. K. RAVALA h. C. WIKLE iii R. h. ZEE B. A. ChIN 275 Wilmore Labs Auburn University Auburn AL 36849-5341 USA

hafnium carbide (hfC) was applied in space and aerospace due to its ultra high melting temperature, high specific strength and moderate oxidation resistance. A novel synthesizing method was used to produce low density and high strength hfC structural foams through the thermolysis and pyrolysis of hf containing polymer precursors (mixing of hafnium trifluoroacetylacetonate and epoxy) under vacuum atmosphere. The X-ray diffraction analysis shows that the produced foam is primarily composed of hfC containing 9%-10% hfO2. Several polymer powder compaction methods were used to improve the mechanical properties of hfC foam. Compression strengths of 200 MPa are achieved for hfC foams with density of 1.9 g/cm(3) (total porosity about 85%). The proposed methodology of synthesizing hfC foam has the advantages of simple, inexpensive and less production time than alternate methods.

关键词：聚合物前提碳化铪结构性泡沫保护性涂层合成力学性质超高温

household air pollution and lung cancer in China:a review of studies in Xuanwei

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Chinese Journal of Cancer 2014年第10期33卷 471-475页

作者： Wei Jie Seow Wei hu Roel Vermeulen h.dea. hosgood iii George S.Downward Robert S.Chapman Xingzhou he Bryan A.Bassig Christopher Kim Cuiju Wen Nathaniel Rothman Qing Lan Division of Cancer Epidemiology and Genetics National Cancer InstituteNational Institutes of Health Institute for Risk Assessment Sciences Division of Environmental EpidemiologyUtrecht University Department of Epidemiology & Population health Albert Einstein College of Medicine College of Public health Sciences Chulalongkorn University Chinese Center for Disease Control and Prevention

Over half of the world's population is exposed to household air pollution from the burning of solid fuels at home. household air pollution from solid fuel use is a leading risk factor for global disease and remains a major public health problem, especially in low- and mid-income countries. This is a particularly serious problem in China, where many people in rural areas still use coal for household heating and cooking. This review focuses on several decades of research carried out in Xuanwei County, Yunnan Province, where household coal use is a major source of household air pollution and where studies have linked household air pollution exposure to high rates of lung cancer. We conducted a series of case-control and cohort studies in Xuanwei to characterize the lung cancer risk in this population and the factors associated with it. We found lung cancer risk to vary substantially between different coal types, with a higher risk associated with smoky(i.e., bituminous) coal use compared to smokeless(i.e., anthracite) coal use. The installation of a chimney in homes resulted in a substantial reduction in lung cancer incidence and mortality. Overall, our research underscores the need among existing coal users to improve ventilation, use the least toxic fuel, and eventually move toward the use of cleaner fuels, such as gas and electricity.

关键词：空气污染家用空调肺癌中国固体燃料公共卫生问题世界人口无烟煤

Extinction of Light in the Galactic halo: First Observational Evidence of the Interaction of Light and Dark Matter

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Journal of Modern Physics 2024年第8期15卷 1144-1198页

作者： Charles h. McGruder iii Department of Physics and Astronomy Western Kentucky University Bowling Green USA

We study the distribution of quasars on the celestial sphere according to ground-based SDSS and space-based WISE and Gaia observations. All distributions as a function of galactic latitude, b, exhibit a decrease in quasar frequency well outside the dust in and near the galactic plane. We prove that the observed decrease in quasar frequency at high galactic latitudes is not accompanied by reddening, meaning that it can not be caused by dust. The scattering of light by the circumgalactic gas is negligible because the Thomson scattering cross section is very small. We conclude the observed scattering of light must be caused by dark matter in the galactic halo. We determine the mass and charge of dark matter particles. If the dark matter particle is a fermion its mass, mDMand charge eDM=δe, where e is the elementary charge are: mDM=3.2×10−2eV and δ=3.856×10−5. If however the dark matter particle is spinless then: mDM=0.511eV and δ=2.132×10−4. These values for the charge of a dark matter particle are orders of magnitude higher than the upper limit of the neutrino charge according to laboratory experiments. Consequently, dark matter particles are not charged neutrinos. Since dark matter particles are charged, they must emit and absorb electromagnetic radiation. however, PDM~δ2, or: PDM~1.487×10−9Pe, where Peis the power output of a single electron.

关键词： Milky Way Dark Matter halo (1049)

Cosmology without the Cosmological Principle and without Violating the Copernican Principle: Taub-NUT Universe

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Journal of Modern Physics 2024年第8期15卷 1069-1096页

作者： Charles h. McGruder iii Department of Physics and Astronomy Western Kentucky University Bowling Green Kentucky USA

We develop a theory of cosmology, which is not based on the cosmological principle. We achieve this without violating the Copernican principle. It is well known that the gravitational redshift associated with the Schwarzschild solution applied to the distant supernova does not lead to the observed redsift-distance relationship. We show, however, that generalizations of the Schwarzschild metric, the Taub-NUT metrics, do indeed lead to the observed redshift-distance relationship and to the observed time dilation. These universes are not expanding rather the observed cosmological redshift is due to the gravitational redshift associated with these solutions. Time dilation in these stationary universes has the same dependency on redshift that generally has been seen as proof that space is expanding. Our theory resolves the hubble tension.

关键词： Cosmology General Relativity

Cosmological Gravitational Redshift, Spectral Shift and Time in the Taub-NUT Universe

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Journal of Modern Physics 2024年第9期15卷 1448-1459页

作者： Charles h. McGruder iii Department of Physics and Astronomy Western Kentucky University Bowling Green Kentucky USA

We demonstrate that: 1) The Taub-NUT universe is finite. 2) The Taub-NUT universe is much larger than the maximum observable distance according to the standard theory of cosmology. 3) At large distances the spectral s... 详细信息

关键词： Cosmology General Relativity

Germs are everywhere; most aren＇t too harmful

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空中英语教室（高级版．彭蒙惠英语） 2009年第10期 17-19页

作者： James h. Burnett iii

Neoadjuvant treatment of rectal cancer:where are we now?

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Gastroenterology Report 2016年第3期4卷 206-209,I0002页

作者： Aparna Kalyan Shaina Rozelle Al Benson iii Developmental Therapeutics Program of Division of hematology&Oncology Robert H.Lurie Comprehensive Cancer Center of Northwestern UniversityChicagoIL USA Division of hematology&Oncology Robert H.Lurie Comprehensive Cancer Center of Northwestern UniversityChicagoIL USA

Introduction Colorectal cancer is the third leading cause of cancer-related mortality in the United States[1].Of this group of patients,approximately 39000 cases of rectal cancer were reported in the US in 20151].Treatment of rectal cancer truly requires combinatorial therapy with surgery,chemotherapy and radiation(RT),which now comprise the cornerstone of treatment for rectal cancer.

关键词： rectal cancer neoadjuvant chemoradiation 5-fluorouracil local recurrence