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High-energy and high-intensity lasers are essential for pushing the boundaries of science. Their development has allowed leaps forward in basic research areas, including laser–plasma interaction, high-energy density science, metrology, biology and medical technology. The Helmholtz International Beamline for Extreme Fields user consortium contributes and operates two high-peak-power optical lasers using the high energy density instrument at the European X-ray free electron laser (EuXFEL) facility. These lasers will be used to generate transient extreme states of density and temperature to be probed by the X-ray beam. This paper introduces the ReLaX laser, a short-pulse high-intensity Ti:Sa laser system, and discusses its characteristics as available for user experiments. It will also present the first experimental commissioning results validating its successful integration into the EuXFEL infrastructure and viability as a relativistic-intensity laser driver. [ABSTRACT FROM AUTHOR]

Small angle x-ray scattering (SAXS) is a well established technique to detect nanometer scale structures in matter. In a typical setup, this diagnostic uses a detector with a direct line of sight to the scattering target. However, in the harsh environment of high intensity laser interaction, intense secondary radiation and high-energy particles are generated. Such a setup would therefore suffer a significant increase of noise due to this background, which could eventually prevent such measurements. In this paper, we present a novel tool consisting of a mosaic graphite crystal that works as a mirror for the SAXS signal and allows us to position the detector behind appropriate shielding. This paper studies the performance of this mirror both by experiment at the European XFEL (X-Ray Free-Electron Laser Facility) laboratory and by simulations. [ABSTRACT FROM AUTHOR]

Here, we report results of an experiment creating a transient, highly correlated carbon state using a combination of optical and x-ray lasers. Scattered x-rays reveal a highly ordered state with an electrostatic energy significantly exceeding the thermal energy of the ions. Strong Coulomb forces are predicted to induce nucleation into a crystalline ion structure within a few picoseconds. However, we observe no evidence of such phase transition after several tens of picoseconds but strong indications for an over-correlated fluid state. The experiment suggests a much slower nucleation and points to an intermediate glassy state where the ions are frozen close to their original positions in the fluid. [ABSTRACT FROM AUTHOR]

Proportional derivative (PD) steering assistance can greatly improve the control stability of a vehicle. However, for all PD steering methods, the discomfort associated with the need to continuously turn the steering wheel during cornering is significant. Because the steering return phenomenon of the steering wheel stop like this is not preferable, PD steering assistance should be extremely weak (almost 0) during normal cornering. Alternatively, during drift cornering, during which the grip area of the tires is exceeded, PD steering assistance is helpful because the driver has good control over counter-steering. Moreover, the use of PD steering assistance is preferable during lane changes because the response and settling of a vehicle is greatly improved when PD steering assistance is used. Based on these considerations, a previous report examined steering method controls in which the PD steering assistance constant was incorporated along with the drivers' perception changes in certain driving situations. This study aimed to determine a suitable PD steering assistance constant in relation to the driving situation. A proper PD steering assistance constant was found to exist for specific driving situations. Based on the results of gaze detection using an eye mark recorder, the study was able to reduce the right and left difference of the gaze at the driver by controlling PD steering assistance using a proper PD steering assistance constant for various driving situations. [ABSTRACT FROM AUTHOR]

The multi-Terawatt laser system, terawatt apparatus for relativistic and nonlinear interdisciplinary science, has been recently installed in the Centre for Plasma Physics at the Queen's University of Belfast. The system will support a wide ranging science program, which will include laser-driven particle acceleration, X-ray lasers, and high energy density physics experiments. Here we present an overview of the laser system as well as the results of preliminary investigations on ion acceleration and X-ray lasers, mainly carried out as performance tests for the new apparatus. We also discuss some possible experiments that exploit the flexibility of the system in delivering pump-probe capability. [ABSTRACT FROM AUTHOR]

Improving the driver's feel for vehicle manipulation under various road conditions is one of the most important issues in the vehicle development process, although the driver's perception of vehicle motion is difficult to quantify. Even if the vehicle's motion is approximately the same under a fixed maneuvering condition, the driver sometimes distinguishes the difference in the drive feel. To analyse this, we measured the driver's head motion up to six degrees of freedom under the steady-state and transient driving conditions with two types of vehicles. The head motion on the steady-state test showed resemblance between those two types of vehicles. In contrast, transient maneuver induced some differences on the driver's head motion and also had effect from steering operation. With these tests, we could make clear the important relation between driver motion and vehicle motion. [ABSTRACT FROM AUTHOR]

Preclinical studies have demonstrated the synergistic anti-tumour activity of combination therapy with the oral cytostatics, 5'-deoxy-5-fluorouridine (5'-DFUR) and cyclophosphamide (CPA), in human breast cancer xenograft models. This study was performed to evaluate the efficacy and safety of this oral combination chemotherapy in the treatment of metastatic breast cancer. In all, 101 patients with metastatic breast cancer were enrolled in the study, and the data for 94 eligible patients of these were evaluated. The patients received twice daily oral combinations of 5'-DFUR (1200 mg/body/day) and CPA (100 mg/body/day) for 2 weeks, followed by a 1-week rest period. After a median of 19 treatment cycles (range 1-66 cycles), 16 patients (17.0%) had a complete response, and 40 patients (42.6%) had partial responses. The response rate was 59.6% (95% CI, 49.0-69.6%). The median time to progression and overall survival times were 11.7 and 40.3 months, respectively. The toxicity was mild and tolerable, and the related grade 3/4 clinical adverse effects consisted of haematological toxicity in 21 patients (22%) and nonhaematological toxicity in five patients (5%). These results suggest that the oral combination chemotherapy of 5'-DFUR and CPA has low toxicity and is a novel, very convenient and effective treatment for metastatic breast cancer. [ABSTRACT FROM AUTHOR]

Ectopic hormone production is very rare in hematological malignancy. Here, we describe an interesting case of acute lymphoblastic leukemia (ALL) with adrenocorticotropic hormone (ACTH) production. A 47-year-old man was admitted to our hospital with a 7-month history of hyperpigmentation. The plasma level of ACTH was markedly elevated without a circadian rhythm and the level of cortisol was normal. Examination of bone marrow aspiration revealed ALL, and no other disease as a cause of the elevated ACTH was detected. Sephadex G-75 chromatography of plasma ACTH extract revealed the existence of an abnormally large molecular ACTH (probably proopiomelanocortin) in addition to authentic 1–39 ACTH. Ectopic ACTH of low biological activity is considered to be the reason for a discrepancy in the plasma levels of ACTH and cortisol. Shortly after remission induction chemotherapy, blast cells in the peripheral blood disappeared, and the plasma level of ACTH became normal, leading to an improvement of skin pigmentation. These clinical findings and laboratory data suggested that leukemia cells in this case may produce the ACTH. [ABSTRACT FROM AUTHOR]

Although CD4+ helper T lymphocytes have been demonstrated to play an important role in antitumor immune response, only a few epitopes of tumor-associated antigens recognized by HLA class II-restricted CD4+ T lymphocytes have been identified. In the present study, we addressed the question of whether leukemia-associated fusion proteins are recognized by CD4+ T lymphocytes. Immature dendritic cells (DCs) were loaded with necrotic or apoptotic leukemia cells with t(6;9) or t(9;22) and then cocultured with the dek-can fusion peptide-specific or the bcr-abl fusion peptide-specific CD4+ T lymphocyte clone. The dek-can peptide-specific and bcr-abl peptide-specific CD4+ T lymphocyte clones produced interferon-γ (IFN-γ) when they were cocultured with HLA-DR-matched but not with mismatched DCs which had been loaded with apoptotic as well as necrotic leukemia cells with t(6;9) and t(9;22), respectively. IFN-γ production by CD4+T lymphocyte clones in response to stimulation with DCs loaded with leukemia cells was inhibited by the anti-HLA-DR monoclonal antibody. These data indicate that the acute myelogenous leukemia-associated fusion protein, dek-can, and chronic myelogenous leukemia-associated fusion protein, bcr-abl, are both processed and presented by DCs to the fusion peptide-specific CD4+ T lymphocytes.Leukemia (2002) 16, 2400–2407. doi:10.1038/sj.leu.2402742 [ABSTRACT FROM AUTHOR]

We perform 2D and 3D numerical simulations of an accretion disc in a close binary system using the simplified flux vector splitting (SFS) finite volume method. In our calculations, the gas is assumed to be ideal with γ=1.01, 1.05, 1.1 and 1.2. The mass ratio of the mass-losing star to the mass-accreting star is unity. Our results show that spiral shocks are formed on the accretion disc in all cases. In 2D calculations we find that the smaller γ is, the more tightly the spiral winds. We observe this trend in 3D calculations as well in a somewhat weaker sense. Mach numbers in our discs are less than 10. These values are lower than the values in observed accretion discs in close binary systems. Recently, Steeghs, Harlaftis & Horne found the first convincing evidence for spiral structure in the accretion disc of the eclipsing dwarf nova binary IP Pegasi, using the technique known as Doppler tomography. Although the Mach numbers in present calculations are rather low, we may claim that the spiral structure that we discovered in earlier numerical simulations is now found observationally. [ABSTRACT FROM AUTHOR]

The pseudoelastic behaviour associated with the martensitic transformation (MT) of TiNi shape memory alloys subjected to strain variations has been investigated experimentally. The results are summarized as follows. Firstly, with respect to strain variations within the MT region: (1) The reverse transformation stress does not depend on the maximum strain. (2) The MT stress and reverse transformation stress decrease with an increase in the number of deformation cycles. (3) The rate of variation in both transformation stresses with cycling decreases with the increase in the number of cycles. Secondly, with respect to strain variations beyond the completion points of MT and reverse transformation: (1) At the start points of MT and of the reverse transformation, over shooting of both transformation stresses appears. (2) The higher the temperature and the larger the maximum strain, the larger the overshoot of both transformation stresses and the larger the decrease of the reverse transformation stress. [ABSTRACT FROM PUBLISHER]

A selective and sensitive method for the simultaneous determination of aliphatic and aromatic aldehydes in cigarette smoke by gas chromatography (GC) has been developed. After trapping of cigarette smoke into dilute hydrochloric acid containing ascorbic acid, aldehydes were converted into their thiazolidine derivatives by the reaction with cysteamine, and then measured by GC with flame photometric detection using two-connected fused-silica capillary columns containing DB-17 and DB-210, respectively. The derivatives were sufficiently volatile and gave single symmetrical peaks. The calibration curves for aliphatic and aromatic aldehydes in the range 20–2000 ng were linear and the detection limits at a signal-to-noise ratio of 3 were ca. 4–100 pg injected. Aliphatic and aromatic aldehydes in cigarette smoke could be selectively determined by this method without any interference from coexisting substances. Overall eecoveries of aldehydes added to cigarette smoke samples were 83–110%. Analytical results for the contents of aliphatic and aromatic aldehydes in mainstream and sidestream smokes of several cigarettes are presented. [ABSTRACT FROM AUTHOR]

A major solar flare on 15 November, 1991 produced a striking perturbation in the position and shape of the sunspot related most closely to the flare. We have studied these perturbations by use of the aspect-sensor images from the Soft X-ray Telescope on board YOHKOH, and with ground-based data from the Mees Solar Observatory. The perturbation occurred during the impulsive phase of the flare, with a total displacement on the order of 1 arc sec. The apparent velocity of approximately 2 km s exceeds that typically reported for sunspot proper motions even in flare events. We estimate that the magnetic energy involved in displacing the sunspot amounted to less than 4 × 10 ergs, comparable to the radiant energy from the perturbed region. Examination of the Mees Observatory data shows that the spot continued moving at lower speed for a half-hour after the impulsive phase. The spot perturbation appears to have been a result of the coronal restructuring and flare energy release, rather than its cause. [ABSTRACT FROM AUTHOR]

The evolution of bismuth crystal structure upon excitation of its A1g phonon has been intensely studied with short pulse optical lasers. Here we present the first-time observation of a hard x-ray induced ultrafast phase transition in a bismuth single crystal at high intensities (~1014 W/cm2). The lattice evolution was followed using a recently demonstrated x-ray single-shot probing setup. The time evolution of the (111) Bragg peak intensity showed strong dependence on the excitation fluence. After exposure to a sufficiently intense x-ray pulse, the peak intensity dropped to zero within 300 fs, i.e. faster than one oscillation period of the A1g mode at room temperature. Our analysis indicates a nonthermal origin of a lattice disordering process, and excludes interpretations based on electron-ion equilibration process, or on thermodynamic heating process leading to plasma formation. [ABSTRACT FROM AUTHOR]

A 32 year old woman and her 32 year old spouse were referred to our IVF programme. Following recovery of 12 mature oocytes, nine were fertilized following conventional IVF. Three fresh embryos were transferred to the uterus, but all failed to result in pregnancy. Six supernumerary embryos were cultured in vitro until day 5 in order to create blastocysts. Two grew to the blastocyst stage and were vitrified using a modification of a previous method. Two blastocysts survived the freeze-thaw process and were transferred to the patient's uterus during a natural cycle, 3 months after the previous retrieval cycle. Implantation resulted in a healthy pregnancy; delivery is expected in June 2000. This report documents the first successful pregnancy in Japan, achieved via blastocyst vitrification. [ABSTRACT FROM AUTHOR]

To improve the utility of mammary ductoscopy, we investigated the correlation between endoscopic findings and histologic findings using intraductal biopsy specimens. Seventy-one intraductal biopsy specimens obtained from 63 patients between October 2001 and March 2004 were analyzed retrospectively. All specimens were obtained from monotonous intraductal lesions immediately after observation by mammary ductoscopy and were composed of a pure histologic subtype. With regard to endoscopic findings, color was classified as yellow, red, white, or colorless, and morphology was classified as spherical, lobular, mulberry, or amorphous. The histologic subtype was classified as papillotubular, papillary, degenerated, papillary cancer, solid-type ductal carcinoma in situ (DCIS), or cribriform cancer. The relationship between histologic diagnosis, color, and morphology was investigated. Intraductal biopsy specimens included 25 specimens of carcinoma and 46 specimens of papilloma. There was no significant correlation between color and diagnosis. Fourteen of 25 carcinoma specimens were amorphous, and amorphous morphology was significantly suggestive of malignancy (p < 0.001). Further, cribriform cancer was associated with amorphous morphology and yellow color. Morphology may be a useful endoscopically delineated parameter for differentiating intraductal lesions. [ABSTRACT FROM AUTHOR]

When breast-conserving therapy was introduced at the Cancer Institute Hospital (CIH) in Tokyo in 1986, we instituted our own strategy as follows: 1) every effort is to be made for complete tumor resection while avoiding deformity of the breast, and 2) radiotherapy (RT) is applied only to the patients with positive surgical margins. This is, in turn, to clarify the group of patients in whom postoperative RT can be safely spared. Among 9670 patients operated on for primary breast cancer during the 16.5 year period from 1986 to 2002 at CIH, there were 2449 patients who underwent breast-conserving surgery (BCS). During the 6.5 years mean follow-up period, ipsilateral intrabreast tumor recurrence (IBTR) developed in 99 of the 2449 patients, with an overall rate of 4.0% and an annual rate of 0.62%. These 2449 patients were categorized into four subgroups according to either negative or positive margins and with or without radiotherapy. The IBTR rates and the number of patients in each subgroup were 5.5% in 1351 margin(-)RT(-) patients, 1.0% in 307 margin(-)RT(+) patients, 2.4% in 680 margin(+)RT(+) patients, and 4.5% in 111 margin(+)RT(-) patients. These results either with or without RT seem to be quite comparable to or even better than the results of BCS with RT reported from Western countries, where less emphasis seems to be placed on completeness of the local tumor resection with BCS, while RT is administered to basically all patients following BCS. IBTR was categorized into true recurrence (TR) and second primary lesion (SP) according to the margin status at the time of BCS, the former being lesions developed in patients with positive margins and the latter being those in patients with negative margins. It was demonstrated that in patients with positive margins, TR was much more common than SP, whereas in patients with negative margins, these incidences were just the opposite (i.e., TR was 60% less common than SP) and postoperative RT was effective in preventing both TR and SP, the effect on the latter being much more striking. With RT, the incidence of developing TR in patients who had positive margins was reduced to almost equal to that in margin(-) patients treated with no RT. Our method of IBTR categorization is based on biological consideration and detailed histopathologic examination, and appears to be the only biologically reasonable means so far that has been proposed for distinction between these two biologically different entities. TR and SP can be further reduced to exceptionally low levels in patients who received RT despite negative margins, though it would not seem reasonable to administer RT to all of these patients because the actual number of patients who would benefit is comparatively small. From these observations, it seems that our imaging, pathologic examination, and surgical approaches for patients who are candidates for BCS have been highly valid, and our criteria for sparing postoperative RT as well as categorization of IBTR into TR and SP are quite appropriate. Although our results with BCS seem to deserve wide recognition, they are not from randomized clinical trials, so the findings must be confirmed by a study in order to investigate whether the results at CIH can be applied generally at other institutions. [ABSTRACT FROM AUTHOR]

When breast-conserving therapy was introduced at the Cancer Institute Hospital (CIH) in Tokyo in 1986, we instituted our own strategy as follows: 1) every effort is to be made for complete tumor resection while avoiding deformity of the breast, and 2) radiotherapy (RT) is applied only to the patients with positive surgical margins. This is, in turn, to clarify the group of patients in whom postoperative RT can be safely spared. Among 9670 patients operated on for primary breast cancer during the 16.5 year period from 1986 to 2002 at CIH, there were 2449 patients who underwent breast-conserving surgery (BCS). During the 6.5 years mean follow-up period, ipsilateral intrabreast tumor recurrence (IBTR) developed in 99 of the 2449 patients, with an overall rate of 4.0% and an annual rate of 0.62%. These 2449 patients were categorized into four subgroups according to either negative or positive margins and with or without radiotherapy. The IBTR rates and the number of patients in each subgroup were 5.5% in 1351 margin(–)RT(–) patients, 1.0% in 307 margin(–)RT(+) patients, 2.4% in 680 margin(+)RT(+) patients, and 4.5% in 111 margin(+)RT(–) patients. These results either with or without RT seem to be quite comparable to or even better than the results of BCS with RT reported from Western countries, where less emphasis seems to be placed on completeness of the local tumor resection with BCS, while RT is administered to basically all patients following BCS. IBTR was categorized into true recurrence (TR) and second primary lesion (SP) according to the margin status at the time of BCS, the former being lesions developed in patients with positive margins and the latter being those in patients with negative margins. It was demonstrated that in patients with positive margins, TR was much more common than SP, whereas in patients with negative margins, these incidences were just the opposite (i.e., TR was 60% less common than SP) and postoperative RT was effective in preventing both TR and SP, the effect on the latter being much more striking. With RT, the incidence of developing TR in patients who had positive margins was reduced to almost equal to that in margin(–) patients treated with no RT. Our method of IBTR categorization is based on biological consideration and detailed histopathologic examination, and appears to be the only biologically reasonable means so far that has been proposed for distinction between these two biologically different entities. TR and SP can be further reduced to exceptionally low levels in patients who received RT despite negative margins, though it would not seem reasonable to administer RT to all of these patients because the actual number of patients who would benefit is comparatively small. From these observations, it seems that our imaging, pathologic examination, and surgical approaches for patients who are candidates for BCS have been highly valid, and our criteria for sparing postoperative RT as well as categorization of IBTR into TR and SP are quite appropriate. Although our results with BCS seem to deserve wide recognition, they are not from randomized clinical trials, so the findings must be confirmed by a study in order to investigate whether the results at CIH can be applied generally at other institutions. [ABSTRACT FROM AUTHOR]