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We have developed an on-line spectrometer for hard x-ray free-electron laser (XFEL) radiation based on a nanostructured diamond diffraction grating and a bent crystal analyzer. Our method provides high spectral resolution, interferes negligibly with the XFEL beam, and can withstand the intense hard x-ray pulses at high repetition rates of >100  Hz. The spectrometer is capable of providing shot-to-shot spectral information for the normalization of data obtained in scientific experiments and optimization of the accelerator operation parameters. We have demonstrated these capabilities of the setup at the Linac Coherent Light Source, in self-amplified spontaneous emission mode at full energy of >1  mJ with a 120 Hz repetition rate, obtaining a resolving power of E/δE>3×10^4. The device was also used to monitor the effects of pulse duration down to 8 fs by analysis of the spectral spike width.

Sentinel node (SN) biopsy is a promising replacement for standard axillary lymph node dissection for the staging of early breast cancer, and various techniques have been studied to identify SNs with dye or radioactive colloid. This study assesses the effect of the dose of radioactivity and the time before biopsy in order to set standards for the use of 99mTc-rhenium sulphide for the detection of SNs in breast cancer patients. Sixty patients with stage T1-2 N0 M0 breast cancer underwent SN biopsy, which was immediately followed by standard axillary dissection to confirm the SN results. For SN biopsy, 99mTc-rhenium colloid was injected peritumorally. A 1 day (morning injection and afternoon surgery) or 2 day (day before afternoon injection and morning surgery) protocol was applied. A dose-finding study was performed simultaneously using 7.4-37 MBq for the 1 day protocol and 37-74 MBq for the 2 day protocol. A scintigram was taken at 2 h for the 1 day protocol and 16 h for the 2 day protocol. After the injection of blue dye, SN biopsy was performed with a gamma probe, followed by standard axillary node dissection. The radiation exposure received by the surgical team during the operation was monitored. Histopathological comparison between SNs and axillary nodes was performed. Patient characteristics that might affect the radiocolloid uptake by SNs were assessed. SNs were identified in all patients regardless of the dose or administration protocol used. Two patients showed false negative pathological SN results, and the negative predictive value was 96 and the positive predictive value was 100. In addition, radiation exposure to the surgical team and the amount of radioactive surgical waste were low, especially at lower doses. Two groups of patient characteristics were related to SN uptake. One was the body mass index (BMI) and the other was the age or menopausal status. Patients with a larger BMI tended to take up a smaller amount of 99mTc colloid. Older or post-menopausal patients showed lower SN uptake. 99mTc-rhenium sulphide colloid is an efficient radiopharmaceutical for SN detection. Both 1 day and 2 day protocols have equally good efficacy, and the recommended dose is 7.4 MBq for the 1 day protocol and 37 MBq for the 2 day protocol. Patients with larger BMI and older or post-menopausal patients tend to take up less 99mTc colloid.

Implantation sites from three strains of immunodeficient mice [tgϵ26, IL-2Rβ null×p56lcknull and IL-2Rγ null, now known as common cytokine chain γ (γc) null], which lack uterine natural killer (uNK) cells, are histologically abnormal. The related anomalies (found from day 10 of gestation) include the absence of aggregation of lymphocytes in the mesometrial triangle, acellularity of the mesometrial decidua, decidual arteries with relatively thick walls and reduced lumen diameters, unusual prominence of the endothelium in the major decidual vessels, and an overall reduction in placental size. In this study we have characterized implantation sites in a new mouse strain (γc−/RAG2−) that is deficient in all lymphoid lineages. We have compared implantation sites in tgϵ26 to γc−/RAG2−at the ultrastructural level in order to determine the earliest-time point at which implantation sites differed from those in immunocompetent mice, and the cell types affected. Implantation sites from both the uNK cell-deficient mice resemble those from random-bred, immunocompetent mice on days 6 and 7 of gestation. On day 8 of gestation, decidual cells on the mesometrial sides of implantation sites in both tgϵ26 and γc−/RAG2−revealed pleotrophic morphology and degeneration. In some vessels, endothelial cells were distorted or displaced from their supporting cells. Progressive changes, suggestive of loss of function of both the mesometrial decidua and endothelial cells, were seen to day 14 of gestation, the latest time-point analysed. In contrast to tgϵ26 mice, homozygously-mated γc−/RAG2−had normal litter sizes, with birthweights and weaning weights similar to congenic C57Bl/6J controls, and no significant perinatal loss. In both strains, the newly-documented endothelial cell lesions predict detrimental alterations to vasomotor function of the uterine vasculature. These studies add strength to the hypothesis that uNK cells may have specialized physiological, rather than classically immune, functions in the pregnant mammalian uterus.

AbstractHigh-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.

To determine how cell proliferation contributes to phosphotyrosine (P-Tyr) level in body we investigated the changes of P-Tyr levels in mouse urine and liver during liver regeneration after partial hepatectomy (PH). After PH, the P-Tyr contents in urine and liver increased approximately 14- and 1.7-fold, respectively, at 2-4 days, and P-Tyr phosphatase activity in liver decreased to 50% at 2 days. These levels returned to the control level at 10 days. After orthovanadate administration, P-Tyr level increased as P-Tyr phosphatase activity decreased. These results suggest that P-Tyr level in liver is reflected in urinary P-Tyr level during liver regeneration, and P-Tyr phosphatase is important in the regulation of P-Tyr level.Copyright 1994, 1999 Academic Press, Inc.

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.

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-1 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 × 1030 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.

We present a method for producing laser beams of nonuniform polarization where the polarization direction rotates on a trajectory about the beam propagation direction. Our method uses a Sagnac interferometer that incorporates a spatial light modulator to combine beams that possess oppositely charged phase vortices in order to achieve the desired polarization vortex. We demonstrate the utility of our method by producing polarization vortices characterized by a fractional index, and we compare the results with calculations of the expected fields.

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.

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.