Spatial profile measurement of femtosecond laser - Compton xrays

Abstract A femtosecond X-ray source was developed by Thomson scattering through interaction between a lowemittance picosecond electron beam and a terawatt femtosecond laser light at 90 o configuration. The observed X-ray intensity with peak energy of 2.3 keV and pulse duration of 270 fs rms was typically 1.4x10 4 photons/pulse. The pulse-to-pulse fluctuation of the X-ray intensity was measured to be 25%. The spatial profile of the X-rays was measured with a technique of X-ray imaging on a phosphor screen using an image-intensified CCD camera. The dependence of the X-ray beam profile on the scattering laser polarization was obtained and compared with theoretical analysis. INTRODUCATION A short pulse X-ray source is an important tool for studying the dynamics of the materials in the fundamental time scale. The development of femtosecond laser has made it possible to generate such ultrashort X-ray pulses in femtosecond region by means of 90-degree (90 o ) Thomson scattering with a relativistic ultrashort-pulse electron beam The intensity of the X-rays generated in Thomson scattering is proportional to the densities of both the electron and laser beam. It is important to tightly focus both the beams in the transverse direction to generate high-brightness X-rays. In addition, the small focused beam size should be required to reduce the interaction time in 90 o Thomson scattering for the generation of femtosecond X-ray pulse EXPERIMENTAL ARRANGEMENT The Thomson femtosecond X-ray source was consisted of a picosecond electron source and a tabletop terawatt femtosecond pulse laser An Electron Source The electron beam was produced by a S-band (2856 MHz) photocathode rf gun. The rf gun, which was constructed under the BNL/KEK/SHI collaboration [6], was consisted of two cells: a half cell and a full cell. A copper cathode was located on the side of the half cell. The length of the half cell was designed to be 0.6 times of the full cell length to reduce the beam divergence. At the exit of the rf gun, a single solenoid magnet was mounted for space-charge emittance compensation. The rf gun was driven by an all solid-state LD-pumped Nd:YAG picosecond laser. The laser was consisted of a passive mode-locked oscillator, a regenerative amplifier, a post amplifier and a frequency converter. The oscillator was phase-locked with a frequency of 119 MHz, the 24 th sub-harmonic of the accelerating 2856 MHz rf, by dynamically adjusting the cavity length of the oscillator with a semiconductor saturable absorber mirror controlled by a timing stabilizer. The output of the oscillator was amplified the pulse energy up to 2mJ in the regenerative amplifier and the post amplifier. The amplified laser pulse was frequency quadrupled to 262 nm ultraviolet (UV) light by a pair of frequency conversion crystals. The UV light was injected on the cathode surface at an incident angle of 68 o along the electron beam direction. The electron beam produced from the rf gun was accelerated with a 70 cm long standing-wave linear accelerator (linac) produced with an alternating-periodic structure. The linac is located at a position of 1.2 m from the cathode. The input rf peak power of both the rf gun and the linac was 7.5 MW that was produced with a 15 MW Klystron. The peak electric fields on axis in the rf gun and the linac were approximately 100 and 25 MV/m, respectively. The repetition rate of the operation was 10 Hz in the experiments. The accelerated electron beam was focused at the interaction point for scattering with the laser light by a triplet quadrupole magnet downstream of the linac. The scattered electrons were bended by a 90 o dipole magnet A Terawatt Femtosecond Laser The terawatt femtosecond laser was consisted of a mode-locked Ti:Sapphire laser oscillator, a pulse stretcher, a regenerative amplifier, a multi-pass post amplifier, and a pulse compressor. The oscillator generated 50 fs pulses at the repetition rate of 119 MHz. The frequency of the laser oscillator was phase-locked with the 119 MHz rf by the same method as the driving laser of the rf gun. ___________________________________________

Single Particle and Fermi Liquid Properties of He-3/--He-4 Mixtures: A Microscopic Analysis

We calculate microscopically the properties of the dilute He-3 component in a He-3/--He-4 mixture. These depend on both, the dominant interaction between the impurity atom and the background, and the Fermi liquid contribution due to the interaction between the constituents of the He-3 component. We first calculate the dynamic structure function of a He-3 impurity atom moving in He-3. From that we obtain the excitation spectrum and the momentum dependent effective mass. The pole strength of this excitation mode is strongly reduced from the free particle value in agreement with experiments; part of the strength is distributed over high frequency excitations. Above k > 1.7$\AA$^{-1}$ the motion of the impurity is damped due to the decay into a roton and a low energy impurity mode. Next we determine the Fermi--Liquid interaction between He-4 atoms and calculate the pressure-- and concentration dependence of the effective mass, magnetic susceptibility, and the He-3--He-3 scattering phase shifts. The calculations are based on a dynamic theory that uses, as input, effective interactions provided by the Fermi hypernetted--chain theory. The relationship between both theories is discussed. Our theoretical effective masses agree well with recent measurements by Yorozu et al. (Phys. Rev. B 48, 9660 (1993)) as well as those by R. Simons and R. M. Mueller (Czekoslowak Journal of Physics Suppl. 46, 201 (1996)), but our analysis suggests a new extrapolation to the zero-concentration limit. With that effective mass we also find a good agreement with the measured Landau parameter F_0^a.Comment: 47 pages, 15 figure

Concentration Dependence of the Effective Mass of He-3 Atoms in He-3/He-4 Mixtures

Recent measurements by Yorozu et al. (S. Yorozu, H. Fukuyama, and H. Ishimoto, Phys. Rev. B 48, 9660 (1993)) as well as by Simons and Mueller (R. Simons and R. M. Mueller, Czhechoslowak Journal of Physics Suppl. 46, 201 (1976)) have determined the effective mass of He-3 atoms in a He-3/He-4 mixture with great accuracy. We here report theoretical calculations for the dependence of that effective mass on the He-3 concentration. Using correlated basis functions perturbation theory to infinite order to compute effective interactions in the appropriate channels, we obtain good agreement between theory and experiment.Comment: 4 pages, 1 figur

DEVELOPMENT OF HIGH-BRIGHTNESS FEMTOSECOND X-RAY SOURCE

Abstract A high-brightness femtosecond X-ray source, based on Thomson scattering of a low-emittance electron beam with a femtosecond pulse laser at a 90-degree interaction configuration, has been developed and will be expected for the study of ultra-fast structural dynamics of materials. The electron beam was generated by a laser-driven photocathode RF gun and accelerated up to 14MeV with a linac. A 270fs pulse X-rays with a peak energy of 2.3keV were achieved experimentally in the interaction of a 3ps electron bunch with a 100fs Ti:Sapphire laser light. The intensity of the X-rays was obtained to be 1.4x10 4 /pulse under the experimental conditions of a 0.5nC electron bunch and a 100mJ laser pulse energy. The stability of the X-ray intensity was obtained to be 25%(rms)

Upregulation of AEBP1 in endothelial cells promotes tumor angiogenesis in colorectal cancer

血管新生は大腸がんの重要な治療標的である．本論文では，大腸がんの腫瘍血管関連遺伝子を探索し，AEBP1（Adipocyte enhancer binding protein 1）の血管内皮細胞における高発現を同定し，AEBP1が腫瘍血管新生促進に働くことを明らかにした

Spin chemistry investigation of peculiarities of photoinduced electron transfer in donor-acceptor linked system

Photoinduced intramolecular electron transfer in linked systems, (R,S)- and (S,S)-naproxen-N-methylpyrrolidine dyads, has been studied by means of spin chemistry methods [magnetic field effect and chemically induced dynamic nuclear polarization (CIDNP)]. The relative yield of the triplet state of the dyads in different magnetic field has been measured, and dependences of the high-field CIDNP of the N-methylpyrrolidine fragment on solvent polarity have been investigated. However, both (S,S)- and (R,S)-enantiomers demonstrate almost identical CIDNP effects for the entire range of polarity. It has been demonstrated that the main peculiarities of photoprocesses in this linked system are connected with the participation of singlet exciplex alongside with photoinduced intramolecular electron transfer in chromophore excited state quenching.This work was supported by the grants 08-03-00372 and 11-03-01104 of the Russian Foundation for Basic Research, and the grant of Priority Programs of the Russian Academy of Sciences, nr. 5.1.5.Magin, I.; Polyakov, N.; Khramtsova, E.; Kruppa, A.; Stepanov, A.; Purtov, P.; Leshina, T.... (2011). Spin chemistry investigation of peculiarities of photoinduced electron transfer in donor-acceptor linked system. Applied Magnetic Resonance. 41(2-4):205-220. https://doi.org/10.1007/s00723-011-0288-3S205220412-4J.S. Park, E. Karnas, K. Ohkubo, P. Chen, K.M. Kadish, S. Fukuzumi, C.W. Bielawski, T.W. Hudnall, V.M. Lynch, J.L. Sessler, Science 329, 1324–1327 (2010)S.Y. Reece, D.G. Nocera, Annu. Rev. Biochem. 78, 673–699 (2009)M.S. Afanasyeva, M.B. Taraban, P.A. Purtov, T.V. Leshina, C.B. Grissom, J. Am. Chem. Soc. 128, 8651–8658 (2006)M.A. Fox, M. Chanon, in Photoinduced Electron Transfer. C: Photoinduced Electron Transfer Reactions: Organic Substrates (Elsevier, New York, 1988), p. 754P.J. Hayball, R.L. Nation, F. Bochner, Chirality 4, 484–487 (1992)N. Suesa, M.F. Fernandez, M. Gutierrez, M.J. Rufat, E. Rotllan, L. Calvo, D. Mauleon, G. Carganico, Chirality 5, 589–595 (1993)A.M. Evans, J. Clin. Pharmacol. 36, 7–15 (1996)Y. Inoue, T. Wada, S. Asaoka, H. Sato, J.-P. Pete, Chem Commun. 4, 251–259 (2000)T. Yorozu, K. Hayashi, M. Irie, J. Am. Chem. Soc. 103, 5480–5548 (1981)N.J. Turro, in Modern Molecular Photochemistry (Benjamin/Cummings, San Francisco, 1978)K.M. Salikhov, Y.N. Molin, R.Z. Sagdeev, A.L. Buchachenko, in Spin Polarization and Magnetic Field Effects in Radical Reactions (Akademiai Kiado, Budapest, 1984), p. 419E.A. Weiss, M.A. Ratner, M.R. Wasielewski, J. Phys. Chem. A 107, 3639–3647 (2003)A.S. Lukas, P.J. Bushard, E.A. Weiss, M.R. Wasielewski, J. Am. Chem. Soc. 125, 3921–3930 (2003)R. Nakagaki, K. Mutai, M. Hiramatsu, H. Tukada, S. Nakakura, Can. J. Chem. 66, 1989–1996 (1988)M.C. Jim′enez, U. Pischel, M.A. Miranda, J. Photochem. Photobiol. C Photochem. Rev. 8, 128–142 (2007)S. Abad, U. Pischel, M.A. Miranda, Photochem. Photobiol. Sci. 4, 69–74 (2005)U. Pischel, S. Abad, L.R. Domingo, F. Bosca, M.A. Miranda, Angew. Chem. Int. Ed. 42, 2531–2534 (2003)G.L. Closs, R.J. Miller, J. Am. Chem. Soc. 101, 1639–1641 (1979)G.L. Closs, R.J. Miller, J. Am. Chem. Soc. 103, 3586–3588 (1981)M. Goez, Chem. Phys. Lett. 188, 451–456 (1992)I.F. Molokov, Y.P. Tsentalovich, A.V. Yurkovskaya, R.Z. Sagdeev, J. Photochem. Photobiol. A 110, 159–165 (1997)U. Pischel, S. Abad, M.A. Miranda, Chem. Commun. 9, 1088–1089 (2003)H. Hayashi, S. Nagakura, Bull. Chem. Soc. Jpn. 57, 322–328 (1984)Y. Sakaguchi, H. Hayashi, S. Nagakura, Bull. Chem. Soc. Jpn. 53, 39–42 (1980)H. Yonemura, H. Nakamura, T. Matsuo, Chem. Phys. Lett. 155, 157–161 (1989)N. Hata, M. Hokawa, Chem. Lett. 10, 507–510 (1981)M. Shiotani, L. Sjoeqvist, A. Lund, S. Lunell, L. Eriksson, M.B. Huang, J. Phys. Chem. 94, 8081–8090 (1990)E. Schaffner, H. Fischer, J. Phys. Chem. 100, 1657–1665 (1996)Y. Mori, Y. Sakaguchi, H. Hayashi, Chem. Phys. Lett. 286, 446–451 (1998)I.M. Magin, A.I. Kruppa, P.A. Purtov, Chem. Phys. 365, 80–84 (2009)K.K. Barnes, Electrochemical Reactions in Nonaqueous Systems (M. Dekker, New York, 1970), p. 560J. Bargon, J. Am. Chem. Soc. 99, 8350–8351 (1977)M. Goez, I. Frisch, J. Phys. Chem. A 106, 8079–8084 (2002)A.K. Chibisov, Russ. Chem. Rev. 50, 615–629 (1981)J. Goodman, K. Peters, J. Am. Chem. Soc. 107, 1441–1442 (1985)H. Cao, Y. Fujiwara, T. Haino, Y. Fukazawa, C.-H. Tung, Y. Tanimoto, Bull. Chem. Soc. Jpn. 69, 2801–2813 (1996)P.A. Purtov, A.B. Doktorov, Chem. Phys. 178, 47–65 (1993)A.I. Kruppa, O.I. Mikhailovskaya, T.V. Leshina, Chem. Phys. Lett. 147, 65–71 (1988)M.E. Michel-Beyerle, R. Haberkorn, W. Bube, E. Steffens, H. Schröder, H.J. Neusser, E.W. Schlag, H. Seidlitz, Chem. Phys. 17, 139–145 (1976)K. Schulten, H. Staerk, A. Weller, H.-J. Werner, B. Nickel, Z. Phys. Chem. 101, 371–390 (1976)K. Gnadig, K.B. Eisenthal, Chem. Phys. Lett. 46, 339–342 (1977)T. Nishimura, N. Nakashima, N. Mataga, Chem. Phys. Lett. 46, 334–338 (1977)M.G. Kuzmin, I.V. Soboleva, E.V. Dolotova, D.N. Dogadkin, High Eng. Chem. 39, 86–96 (2005

Erlotinib inhibits osteolytic bone invasion of human non-small-cell lung cancer cell line NCI-H292

Previous preclinical and clinical findings have suggested a potential role of epidermal growth factor receptor (EGFR) in osteoclast differentiation and the pathogenesis of bone metastasis in cancer. In this study, we investigated the effect of erlotinib, an orally active EGFR tyrosine kinase inhibitor (TKI), on the bone invasion of human non-small-cell lung cancer (NSCLC) cell line NCI-H292. First, we established a novel osteolytic bone invasion model of NCI-H292 cells which was made by inoculating cancer cells into the tibia of scid mice. In this model, NCI-H292 cells markedly activated osteoclasts in tibia, which resulted in osteolytic bone destruction. Erlotinib treatment suppressed osteoclast activation to the basal level through suppressing receptor activator of NF-κB ligand (RANKL) expression in osteoblast/stromal cell at the bone metastatic sites, which leads to inhibition of osteolytic bone destruction caused by NCI-H292 cells. Erlotinib inhibited the proliferation of NCI-H292 cells in in vitro. Erlotinib suppressed the production of osteolytic factors, such as parathyroid hormone-related protein (PTHrP), IL-8, IL-11 and vascular endothelial growth factor (VEGF) in NCI-H292 cells. Furthermore, erlotinib also inhibited osteoblast/stromal cell proliferation in vitro and the development of osteoclasts induced by RANKL in vitro. In conclusion, erlotinib inhibits tumor-induced osteolytic invasion in bone metastasis by suppressing osteoclast activation through inhibiting tumor growth at the bone metastatic sites, osteolytic factor production in tumor cells, osteoblast/stromal cell proliferation and osteoclast differentiation from mouse bone marrow cells

Direct gating and mechanical integrity of Drosophila auditory transducers require TRPN1

The elusive transduction channels for hearing are directly gated mechanically by the pull of gating springs. We found that the transient receptor potential (TRP) channel TRPN1 (NOMPC) is essential for this direct gating of Drosophila auditory transduction channels and that the channel-spring complex was disrupted if TRPN1 was lost. Our results identify TRPN1 as a mechanical constituent of the fly's auditory transduction complex that may act as the channel and/or gating spring

A novel biomarker TERTmRNA is applicable for early detection of hepatoma

<p>Abstract</p> <p>Backgrounds</p> <p>We previously reported a highly sensitive method for serum human telomerase reverse transcriptase (hTERT) mRNA for hepatocellular carcinoma (HCC). α-fetoprotein (AFP) and des-γ-carboxy prothrombin (DCP) are good markers for HCC. In this study, we verified the significance of hTERTmRNA in a large scale multi-centered trial, collating quantified values with clinical course.</p> <p>Methods</p> <p>In 638 subjects including 303 patients with HCC, 89 with chronic hepatitis (CH), 45 with liver cirrhosis (LC) and 201 healthy individuals, we quantified serum hTERTmRNA using the real-time RT-PCR. We examined its sensitivity and specificity in HCC diagnosis, clinical significance, ROC curve analysis in comparison with other tumor markers, and its correlations with the clinical parameters using Pearson relative test and multivariate analyses. Furthermore, we performed a prospective and comparative study to observe the change of biomarkers, including hTERTmRNA in HCC patients receiving anti-cancer therapies.</p> <p>Results</p> <p>hTERTmRNA was demonstrated to be independently correlated with clinical parameters; tumor size and tumor differentiation (P < 0.001, each). The sensitivity/specificity of hTERTmRNA in HCC diagnosis showed 90.2%/85.4% for hTERT. hTERTmRNA proved to be superior to AFP, AFP-L3, and DCP in the diagnosis and underwent an indisputable change in response to therapy. The detection rate of small HCC by hTERTmRNA was superior to the other markers.</p> <p>Conclusions</p> <p>hTERTmRNA is superior to conventional tumor markers in the diagnosis and recurrence of HCC at an early stage.</p

Tri-Modality therapy with I-125 brachytherapy, external beam radiation therapy, and short- or long-term hormone therapy for high-risk localized prostate cancer (TRIP): study protocol for a phase III, multicenter, randomized, controlled trial

<p>Abstract</p> <p>Background</p> <p>Patients with high Gleason score, elevated prostate specific antigen (PSA) level, and advanced clinical stage are at increased risk for both local and systemic relapse. Recent data suggests higher radiation doses decrease local recurrence and may ultimately benefit biochemical, metastasis-free and disease-specific survival. No randomized data is available on the benefits of long-term hormonal therapy (HT) in these patients. A prospective study on the efficacy and safety of trimodality treatment consisting of HT, external beam radiation therapy (EBRT), and brachytherapy (BT) for high-risk prostate cancer (PCa) is strongly required.</p> <p>Methods/Design</p> <p>This is a phase III, multicenter, randomized controlled trial (RCT) of trimodality with BT, EBRT, and HT for high-risk PCa (TRIP) that will investigate the impact of adjuvant HT following BT using iodine-125 (¹²⁵I-BT) and supplemental EBRT with neoadjuvant and concurrent HT. Prior to the end of September 2012, a total of 340 patients with high-risk PCa will be enrolled and randomized to one of two treatment arms. These patients will be recruited from more than 41 institutions, all of which have broad experience with ¹²⁵I-BT. Pathological slides will be centrally reviewed to confirm patient eligibility. The patients will commonly undergo 6-month HT with combined androgen blockade (CAB) before and during ¹²⁵I-BT and supplemental EBRT. Those randomly assigned to the long-term HT group will subsequently undergo 2 years of adjuvant HT with luteinizing hormone-releasing hormone agonist. All participants will be assessed at baseline and every 3 months for the first 30 months, then every 6 months until 84 months from the beginning of CAB.</p> <p>The primary endpoint is biochemical progression-free survival. Secondary endpoints are overall survival, clinical progression-free survival, disease-specific survival, salvage therapy non-adaptive interval, and adverse events.</p> <p>Discussion</p> <p>To our knowledge, there have been no prospective studies documenting the efficacy and safety of trimodality therapy for high-risk PCa. The present RCT is expected to provide additional insight regarding the potency and limitations of the addition of 2 years of adjuvant HT to this trimodality approach, and to establish an appropriate treatment strategy for high-risk PCa.</p> <p>Trial registration</p> <p>UMIN000003992</p