The linear arboricity of planar graphs with no short cycles

AbstractThe linear arboricity of a graph G is the minimum number of linear forests which partition the edges of G. Akiyama, Exoo and Harary conjectured that ⌈Δ(G)2⌉≤la(G)≤⌈Δ(G)+12⌉ for any simple graph G. In the paper, it is proved that if G is a planar graph with Δ≥7 and without i-cycles for some i∈{4,5}, then la(G)=⌈Δ(G)2⌉

Research on the Effect of Light and Heat Sensing along Meridian of Chinese Medicine

INTRODUCTION: Photonics refers to the technology of generating and harnessing light and other forms of radiant energy whose quantum unit is the photon. Photonic technology in the meridian and acupoints research has shown the unique advantages, by which the microcosmic material basis and macroscopic phenomena research can be integrated to interpret the occurrence of propagated sensation along meridian (PSM) and its underlying mechanism. This study seeks to investigate light and heat sensing action along meridian.METHODS: From the modern research of meridian point of view, PSM is the break point to research the essentiality of meridian. The bio-photonic feature of meridian is the most promising research direction to investigate the PSM phenomena for its contribution to prove the existence of meridian objectively and spontaneously. Therefore, the bio-photonic features of meridian under physiological, pathological, therapeutic, and mechanical conditions were analyzed. Firstly, the four aspects of light sensing action were discussed, i.e. light sensing effect along meridian, blocking effect, laser induced effect and underlying mechanism of light sensing action along meridian. Secondly, the four items of heat sensing action were discussed as well, i.e. thermo-effects, heat perception ability, laser induced heat effect, underlying mechanism on heat sensing effect along meridian.RESULTS: The authors point out that photonic technology, e.g. ultra-weak luminescence, photonic imaging, infrared imaging and infrared spectrum analysis, biological photons detection and laser Doppler application, can achieve purposes of in vivo, dynamic, multiple comparable studies. Thereby, the effect of light and heat sensing along meridian can be detected and illustrated by the use of natural science. The effect of light sensing and heat sensing along meridians with the help of advantages of photonics is expected to interpret and quantify the meridian doctrine, to provide an important experimental basis for meridians and acupoint properties of light and heat, to find a kind of non-invasive diagnostic technique, and to promote the integration and development of meridians and modern medicine.CONCLUSION: Light and heat information can be investigated to analyze the relationship between zang-fu organs and meridians, and the functional characteristics of the meridian. Hence, the effect of light and heat sensing along meridian is the break point of the research of photonics in meridian, which is beneficial to further study the meridian optics

10-Ethyl-3-(5-methyl-1,3,4-oxadiazol-2-yl)-10H-phenothia­zine

In the title compound, C17H15N3OS, the phenothia­zine ring system is slightly bent, with a dihedral angle of 13.68 (7)° between the benzene rings. The dihedral angle between the oxadiazole ring and the adjacent benzene ring is 7.72 (7)°. In the crystal, a π–π inter­action with a centroid–centroid distance of 3.752 (2) Å is observed between the benzene rings of neighbouring mol­ecules

Simultaneous splicing of multiple DNA fragments in one PCR reaction

BACKGROUND: Rapid and simultaneous splicing of multiple DNA fragments is frequently required in many recombinant DNA projects. However, former overlap extension PCRs, the most common methods for splicing DNA fragments, are not really simultaneous fusing of multiple DNA fragments. RESULTS: We performed an optimized method which allowed simultaneous splicing of multiple DNA fragments in one PCR reaction. Shorter outermost primers were prior mixed with other PCR components at the same time. A sequential thermo cycling program was adopted for overlap extension reaction and amplification of spliced DNA. Annealing temperature was relatively higher in the overlap extension reaction stage than in the fused DNA amplification. Finally we successfully harvested target PCR products deriving from fusion of two to seven DNA fragments after 5–10 cycles for overlap extension reaction and then 30 cycles for fused DNA amplification. CONCLUSIONS: Our method provides more rapid, economical and handy approach to accurately splice multiple DNA fragments. We believe that our simultaneous splicing overlap extension PCR can be used to fuse more than seven DNA fragments as long as the DNA polymerase can match

Characterization and identification of in vitro metabolites of (-)-epicatechin using ultra-high performance liquid chromatography-mass spectrometry

Purpose: To characterize and identify metabolites of (-)-epicatechin in microsomal fraction of rat hepatocytes (MFRHs). Methods: A single incubation of (-)-epicatechin (1 mL, 50 µg/mL) in MFRH (0.5 mg/mL) was used for the generation of metabolites. Thereafter, the sample was subjected to protein precipitation prior to analysis with ultra-high performance liquid chromatography coupled to linear ion-trap orbitrap mass spectrometry (UHPLC-LTQ-Orbitap MS). Results: Nine metabolites of (-)-epicatechin were characterized on the basis of high resolution mass measurement, MS spectra and literature data. Based on their structures, the major metabolic routes of (-)-epicatechin in MFRHs were identified as hydroxylation, dihydroxylation and glycosylation. Conclusion: This is the first report on metabolites of (-)-epicatechin in MFRHs, and it is helpful in gaining deeper insight into the metabolism of (-)-epicatechin in vivo. The results will also provide guidance in research on the pharmacokinetics of new drugs. Keywords: (-)-Epicatechin, Metabolites, Hydroxylation, Dihydroxylation, Glycosylation, Rat liver microsomes, Pharmacokinetic studie

Curcumin Blocks Small Cell Lung Cancer Cells Migration, Invasion, Angiogenesis, Cell Cycle and Neoplasia through Janus Kinase-STAT3 Signalling Pathway

Curcumin, the active component of turmeric, has been shown to protect against carcinogenesis and prevent tumor development. However, little is known about its anti-tumor mechanism in small cell lung cancer (SCLC). In this study, we found that curcumin can inhibit SCLC cell proliferation, cell cycle, migration, invasion and angiogenesis through suppression of the STAT3. SCLC cells were treated with curcumin (15 µmol/L) and the results showed that curcumin was effective in inhibiting STAT3 phosphorylation to downregulate of an array of STAT3 downstream targets ,which contributed to suppression of cell proliferation, loss of colony formation, depression of cell migration and invasion. Curcumin also suppressed the expression of proliferative proteins (Survivin, Bcl-XL and Cyclin B1), and invasive proteins (VEGF, MMP-2, MMP-7 and ICAM-1).Knockdown of STAT3 expression by siRNA was able to induce anti-invasive effects in vitro. In contrast, activation of STAT3 upstream of interleukin 6 (IL-6) leads to the increased cell proliferation ,cell survival, angiogenesis, invasion, migration and tumor growth. Our findings illustrate the biologic significance of IL-6/JAK/STAT3 signaling in SCLC progression and providenovel evidence that the pathway may be a new potential target for therapy of SCLC. It was concluded that curcumin is a potent agent in the inhibition of STAT3 with favorable pharmacological activity,and curcumin may have translational potential as an effective cancer therapeutic or preventive agent for SCLC

Enhancement of polar phases in PVDF by forming PVDF/SiC nanowire composite

Different contents of silicon carbide (SiC) nanowires were mixed with Poly(vinylidene fluoride) (PVDF) to facilitate the polar phase crystallization. It was shown that the annealing temperature and SiC content affected on the phase and crystalline structures of PVDF/SiC samples. Furthermore, the addition of SiC nanowire enhanced the transformation of non-polar α phase to polar phases and increased the relative fraction of β phase in PVDF. Due to the nucleating agent mechanism of SiC nanowires, the ion-dipole interaction between the negatively charged surface of SiC nanowires and the positive CH2 groups in PVDF facilitated the formation of polar phases in PVDF