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We study two-loop corrections to the scattering amplitude of four massive leptons in quantum electrodynamics. These amplitudes involve previously unknown elliptic Feynman integrals, which we compute analytically using the differential equation method. In doing so, we uncover the details of the elliptic geometry underlying this scattering amplitude and show how to exploit its properties to obtain compact, easy-to-evaluate series expansions that describe the scattering of four massive leptons in QED in the kinematical regions relevant for Bhabha and Møller scattering processes.
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Atmospheric particle number size distributions were measured by a wide-range particle size spectrometer and a scanning mobility particle size spectrometer in the summertime and wintertime in the coastal area of Qingdao (China). The inorganic and organic gaseous precursors and particulate chemical composition were measured to characterize new particle formation (NPF) events by combining meteorological parameters and backward trajectories. In summer, the occurrence frequency of NPF events was 18% lower. However, the atmospheric particle number concentration increased by approximately 1-4 times during the NPF events compared with those without NPF. The apparent formation rates and growth rates were (5.2±4.3) cm-3·s-1 and (6.5±2.2) nm·h-1, respectively, except for a special NPF event on July 20. The correlation analysis results implied that biogenic volatile organic compounds (BVOCs) seemingly favor NPF, and the reverse is true for anthropogenic volatile organic compounds (AVOCs). The occurrence frequency of NPF events of 27% in winter was clearly higher than that in summer. The apparent formation rates and growth rates, i.e., (3.3±3.1) cm-3·s-1 and (5.3±3.3) nm·h-1, decreased, although the decreases were not significant (P>0.05). The correlation analyses implied that AVOCs favored NPF. However, BVOCs had no correlation with NPF. For the cases in which new particles could grow to CCN sizes (>50 nm), the particle growth characteristics showed significant seasonal differences, i.e., in summer, new particles could grow to CCN sizes via photochemical reactions, whereas in winter, second-stage growth driven by the formation of nitrate aerosols was needed to grow new particles to CCN sizes.
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We report a calculation of the perturbative matching coefficients for the transverse-momentum-dependent parton distribution functions for quark at the next-to-next-to-next-to-leading order in QCD, which involves calculation of nonstandard Feynman integrals with rapidity divergence. We introduce a set of generalized integration-by-parts equations, which allows an algorithmic evaluation of such integrals using the machinery of modern Feynman integral calculation.
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The objective evaluation of human settlement in cities helps find the problems exposed in urban development and make targeted adjustments to improve urban environment. Taking the downtown of Fuzhou as the research area, the residential area as the research unit, using multi-source data such as meteorological monitoring data, remote sensing imagery, map points of interest data (POI), and land planning data, we constructed monitoring system of urban human settlement from four aspects: environmental health and comfort, traffic convenience, city safety, and life conve-nience. The TOPSIS method was used to conduct a comprehensive evaluation of human settlement. The results showed that the human settlement level of downtown Fuzhou was quite different, which was high in the central area and low in the peripheral areas. The human settlement index was high in the middle of the urban area, low in the eastern and southern areas, with mixed high and low values in the western and northern areas. In each index layer, the characteristics of high-high agglomeration and low-low agglomeration of traffic convenience and life convenience were consistent with the distribution of high and low value clusters of the human settlement. Convenient transportation and complete service facilities had a greater impact on human settlement. The environmental health and comfort were characterized by interior low and edge high of the city, while city safety was characterized by interior high and edge low.
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Monitoramento Ambiental , Meios de Transporte , Cidades , HumanosRESUMO
BACKGROUND: Clinical study has demonstrated that the traditional Chinese medicine Qiliqiangxin (QLQX) has protective effects on heart failure. Phenylephrine (PE) is an important inducing factor for cardiac hypertrophy and our previous studies have showed that QLQX attenuates PE-induced cardiac hypertrophy. Besides, QLQX protects against cardiac remodeling after myocardial infarction via activating PPARγ. However, whether QLQX prevents PE-induced cardiac hypertrophy through PPARγ and its coactivator PGC-1α is still unknown. METHODS: The effects of QLQX were investigated based on PE induced cardiac hypertrophy mouse models. Echocardiography and hematoxylin-eosin (HE) staining were used to determine cardiac function and cross-sectional area, respectively. Quantitative real time PCR (qRT-PCR) was used to determine ANP and BNP expressions. Based on primary neonatal rat ventricular cardiomyocytes (NRVMs) treated with PE, the cell size and expressions of ANP and BNP were determined by immunofluorescent staining and qRT-PCR, respectively. In addition, western blot was used to determine PPARγ and PGC-1α expressions. RESULTS: In present study, we confirmed that QLQX could significantly attenuate cardiac hypertrophy in mice treated with PE. Then we showed that PPARγ and PGC-1α were downregulated in PE-induced cardiac hypertrophy, and QLQX could block the decrease of PPARγ and PGC-1α both in vitro and in vivo. Importantly, we found that PPARγ inhibitors or PGC-1α siRNAs eliminated the protective effects of QLQX on PE-induced cardiac hypertrophy. CONCLUSIONS: Our study suggested that QLQX prevents from PE-induced cardiac hypertrophy by activating PPARγ and its coactivator PGC-1α.
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Surface grafting of polyelectrolyte brush, such as 3-sulfopropyl methacrylate potassium salt (SPMK), on hip implant materials has been reported to reduce the wear of the orthopaedic bearing surface. However, the biotribocorrosion behaviour of the SPMK brush has not been taken into consideration in previous research. In the present study, SPMK was grafted on Co28Cr6Mo alloy through photo-induced polymerization, and the biotribocorrosion behaviour was investigated by a series of frictional-electrochemical tests using a universal materials tester combined with an electrochemical measurement (three-electrode) system. Co28Cr6Mo disk and polyethylene (PE) pin were used as the contact pair, and the lubricants were 0.9% saline solution (NaCl) and 0.9% saline solution coupled with 25% bovine serum albumin (BSA). The results showed that SPMK was successfully grafted on Co28Cr6Mo alloy, which was confirmed by the comparison of Raman spectroscopy and static contact angle of the samples before and after surface modification. The greatly reduced electrochemical parameters such as corrosion current and pitting potential indicated that the corrosion rate of Co28Cr6Mo alloy was significantly reduced following SPMK grafting. Additionally, the frictional-electrochemical coupled measurement performed under reciprocating sliding demonstrated that the lowest corrosion current was obtained for the SPMK-grafted Co28Cr6Mo disk, with 0.9% NaCl coupled with 25% BSA as the electrolyte. It is indicated from the present study that SPMK polyelectrolyte brush can greatly improve the anti-biotribocorrosion properties of Co28Cr6Mo alloy, and thus has potential application on surface modification of hip implant materials.
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Prótese de Quadril , Metacrilatos/química , Polietileno/química , Vitálio/química , Corrosão , Eletrólitos , Análise de Falha de Equipamento , Fricção , Lubrificação , Teste de Materiais , Desenho de Prótese , Propriedades de SuperfícieRESUMO
Photophysical photochemical properties, in vitro photodynamic anticancer activity and interaction with albumin of a new axially modified silicon phthalocyanine, i. e. di (2-amino-6-trifluoromethyl-4-pyrimidinyloxy) silicon phthalocyanine (SiPcF), were studied in the present paper. The Q band maximum absorption of SiPcF located at 686 nm with the molar absorption coefficient of 2.3 x 10(5) mol(-1) * L * cm(-1). The fluorescence emission of SiPcF peaked at 694 nm with a fluorescence quantum yield of 0.46. Its singlet oxygen quantum yield produced by photosensitization is 0.38, suggesting that SiPcF is an effective 1O2 photosensitizer. There is strong interaction between SiPcF and bovine serum albumin (BSA). The binding constant is 4.33 x 10(5) mol X L(-1) and the number of binding sites is 1. In vitro experiments show that SiPcF had a high photodynamic anticancer activity against human hepatoma cells HepG2 with an IC50 value down to 5 x 10(-7) mol X L(-1).
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Antineoplásicos , Indóis/química , Compostos de Organossilício/química , Pirimidinas/química , Soroalbumina Bovina/química , Espectrometria de Fluorescência , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Bovinos , Células Hep G2 , Humanos , Indóis/farmacologia , Compostos de Organossilício/farmacologiaRESUMO
With homologous DNA probes, we had screened a grass carp heat shock protein 90 gene (CiHsp90). The full sequence of CiHsp90 cDNA was 2793 bp, which could code a 798 amino acids peptide. The phylogenetic analysis demonstrated that CiHsp90 shared the high homology with Zebrafish Grp94. Quantitative RT-PCR analysis showed that CiHsp90 was ubiquitously expressed at lower levels in all detected tissues and up-regulated after heat shock at 34 °C or cold stress at 4 °C. To understand the function of CiHsp90 involving in thermal protection, an expression vector containing coding region cDNA was expressed in E. coli BL21 (DE3) plysS. Upon transfer from 37 °C to 42 °C, these cells that accumulated CiHsp90 peptides displayed greater thermoresistance than the control cells. While incubated at 4°C for different periods, it could also improve the cell viability. After transient transfected recombinant plasmid pcDNA3.1/CiHsp90 into mouse myeloma cell line SP2/0, we found that CiHsp90 could contribute to protecting cells against both thermal and cold extremes. On the contrary, the mutant construct ΔN-CiHsp90 (256-798aa) could abolish the protection activity both in prokaryotic cells and eukaryotic cells. Additionally, both CiHsp90 and ΔN-CiHsp90 peptides could reduce the level of citrate synthase aggregation at the high temperature.
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Carpas/genética , Carpas/metabolismo , Expressão Gênica , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/metabolismo , Temperatura Alta , Estresse Fisiológico , Animais , Carpas/classificação , Linhagem Celular Tumoral , Células Cultivadas , Citrato (si)-Sintase/genética , Temperatura Baixa , Escherichia coli/genética , Perfilação da Expressão Gênica , Proteínas de Choque Térmico HSP90/química , Camundongos , Dados de Sequência Molecular , Mutação , Filogenia , Homologia de Sequência de Aminoácidos , Estresse Fisiológico/genéticaRESUMO
Two novel axially substituted phthalocyanines, namely bis(4-(4-acetylpiperazine)phenoxy)phthalocyaninatosilicon (IV) (1) and its N-methylated derivative 2, have been synthesized. The dicationic phthalocyanine 2 is non-aggregated in water and exhibits good photophysical properties. The non-covalent BSA conjugates of these compounds have also been prepared. Compound 2 and the conjugate 2-BSA show extremely high photodynamic activities toward B16 melanoma cancer cell lines. The corresponding 50% growth-inhibitory (IC50) ratios are 33 and 38 nM, respectively.