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In conical refraction (CR), a focused Gaussian input beam passing through a biaxial crystal and parallel to one of the optic axes is transformed into a pair of concentric bright rings split by a dark (Poggendorff) ring at the focal plane. Here, we show the generation of a CR transverse pattern that does not present the Poggendorff fine splitting at the focal plane, i.e., it forms a single light ring. This light ring is generated from a nonhomogeneously polarized input light beam obtained by using a spatially inhomogeneous polarizer that mimics the characteristic CR polarization distribution. This polarizer allows modulating the relative intensity between the two CR light cones in accordance with the recently proposed dual-cone model of the CR phenomenon. We show that the absence of interfering rings at the focal plane is caused by the selection of one of the two CR cones.

We demonstrate the transformation of Gaussian input beams into super-Gaussian beams with a quasi flat-top transverse profile by means of the conical refraction phenomenon by adjusting the ratio between the ring radius and the waist radius of the input beam to 0.445. We discuss the beam propagation of the super-Gaussian beam and show that it has a confocal parameter three times larger than the one that would be obtained from a Gaussian beam. The experiments performed with a KGd(WO_4)_2 biaxial crystal are in good agreement with the theoretical predictions.

In 1980, Espey proposed a famous hypothesis that mammalian ovulation is comparable to an inflammatory reaction and many researches have proved the validity of his hypothesis in the last three decades. For example, interleukin (IL)-1, IL-6, tumor necrosis factor (TNF)-, granulocyte-macrophage colony-stimulating factor (GM-CSF), macrophage colony-stimulating factor (M-CSF) and other inflammatory cytokines presence was proven in the preovulatory follicle. Since granulocyte is the major leukocyte and it plays a very important role during inflammation, the importance of granulocyte and its related cytokine, granulocyte colony-stimulating factor (GCSF) in the mechanism of human ovulation is easily predictable. G-CSF is one of the hemopoietic cytokines and it has strong positive effects on granulocytes. G-CSF increases the number of granulocytes and it improves the function of granulocytes. In this review, the participation of leukocytes in the ovulation mechanism is demonstrated first. Second, the participation of G-CSF is shown in comparison with the above mentioned cytokines. Finally, since G-CSF has been used for more than 20 years as a medicine without severe side effects in the field of oncology, the clinical application of G-CSF for the treatment of an ovulation disorder, luteinized unruptured follicle (LUF), will be discussed.

Ovulation has several similarities with inflammation and is closely connected to the activity of leukocytes and inflammatory cytokines. Since granulocytes are one of the major leukocytes, we focused our attention on the presence and local production of granulocyte colony-stimulating factor (G-CSF) in the human ovary.

A detailed nonstationary model of a He — Ar laser pumped by a hard ioniser is developed. It is found by numerical simulation that the pumping of the upper laser level is governed either by the three-body recombination of atomic argon ions with electrons or the dissociative recombination of molecular argon ions with electrons, depending on the argon content in a gas mixture. The conversion of dimer molecular argon ions into trimers, the quenching of the upper laser level by neutral atoms, and the spectral line broadening determine the optimum lasing conditions for the total mixture pressure and the partial argon pressure for different excitation conditions. The model adequately describes experiments using electron beam and nuclear pumping. The optimisation of a 1.79-μm nuclear-pumped He — Ar laser in the VIR-2M reactor gave a maximum laser efficiency of 1.2 %.

Abstract: This paper presents methods using a large number of quantitative indicators of the overall estimation of national S&T activity. The methods collected here apply multivariate analysis techniques to a set of S&T indicators to investigate its structure and extract a single or a small number of indicators of S&T activity. We perform structural analysis and integration of 14 main S&T indicators in 5 countries, the U.S., Japan, Germany, France and the U.K. Latent variables underlying this set of indicators naturally emerge from this analysis, and from these we were able to extract valuable information concerning the nature of S&T activity in each country. This method was also useful for investigating the nature and interpretation, as well as the reliability, of previous S&T indicators.

Bone marrow stromal cells are essential for B-lymphocyte development. However, how stromal cells regulate B lymphopoiesis is not clear. In this paper, we report the molecular cloning of a stromal cell line-derived glycosyl-phosphatidylinositol-anchored molecule, BST-1, that facilitates pre-B-cell growth. The deduced amino acid sequence of BST-1 exhibited 33% identity with CD38. BST-1 was expressed in a wide range of tissues and in umbilical vein endothelial cells, whereas it was scarcely expressed in a variety of hematopoietic cell lines. The gene for BST-1 was assigned to chromosome 14q32.3, where immunoglobulin heavy-chain genes are clustered. BST-1 expression was enhanced in rheumatoid arthritis patient-derived bone marrow stromal cell lines that were previously shown to have an enhanced ability to support the growth of a pre-B-cell line as compared with stromal cell lines derived from healthy donors.

AM-1155 is a new quinolone with a wide spectrum of antibacterial activity against various bacteria including anaerobes and Mycoplasma pneumoniae. AM-1155 was 2- to 16-fold more active than ciprofloxacin and ofloxacin against Staphylococcus aureus including methicillin-resistant strains, Staphylococcus epidermidis, Streptococcus pneumoniae, and Enterococcus faecalis; its MICs for 90% of strains tested were 0.10 to 0.78 micrograms/ml. The activity of AM-1155 was comparable to that of ciprofloxacin against members of the family Enterobacteriaceae, Branhamella catarrhalis, Haemophilus influenzae, and Neisseria gonorrhoeae, but was fourfold less than that of ciprofloxacin against Pseudomonas aeruginosa. Against Xanthomonas maltophilia, Acinetobacter calcoaceticus, and Campylobacter jejuni, AM-1155 was two- to fourfold more active than ciprofloxacin. At a concentration of 1.56 micrograms/ml, AM-1155 inhibited 90% of Bacteroides fragilis strains tested; its activity was 8- to 10-fold higher than those of ofloxacin and ciprofloxacin. Development of resistance to AM-1155 in S. aureus and S. epidermidis occurred at a lower frequency than did that to ciprofloxacin after eight transfers in the presence of drug. In the oral treatment of mouse systemic infections, AM-1155 was four- to eightfold more effective than ciprofloxacin against gram-positive cocci and was as active as ciprofloxacin against gram-negative rods. The efficacy of an oral or a subcutaneous dose of AM-1155 was two- to fivefold greater than that of ofloxacin. Against experimental pneumonia with Klebsiella pneumoniae and P. aeruginosa, AM-1155 was two- to fourfold more active than ciprofloxacin and ofloxacin. AM-1155 also had good efficacy against mouse ascending urinary tract infections with Escherichia coli and P. aeruginosa. These results suggest that AM-1155 may be a potent antibacterial agent applicable to various infections.

AM-1155, a novel fluoroquinolone, exhibited potent activity against Streptococcus pneumoniae, including penicillin-resistant strains; the MIC90 for 48 clinical isolates was 0.25 mg/L. The antibacterial activity of AM-1155 against S. pneumoniae was higher than that of levofloxacin (MIC90 1 mg/L) and comparable with that of sparfloxacin. The MIC90s of penicillin G and erythromycin were 2 and > 4 mg/L, respectively. AM-1155 showed no cross-resistance to penicillin or erythromycin. For experimental murine pneumonia with S. pneumoniae intermediately resistant to penicillin, oral administration of AM-1155 showed efficacy higher than that of levofloxacin and equal to that of sparfloxacin. The efficacy of AM-1155 was also equal to that of subcutaneous penicillin G administration at the same dosage.

AM-1155, a novel fluoroquinolone, exhibited potent activity against Streptococcus pneumoniae, including penicillin-resistant strains; the MIC90 for 48 clinical isolates was 0.25 mg/L. The antibacterial activity of AM-1155 against S. pneumoniae was higher than that of levofloxacin (MIC90 1 mg/L) and comparable with that of sparfloxacin. The MIC90s of penicillin G and erythromycin were 2 and > 4 mg/L, respectively. AM-1155 showed no cross-resistance to penicillin or erythromycin. For experimental murine pneumonia with S. pneumoniae intermediately resistant to penicillin, oral administration of AM-1155 showed efficacy higher than that of levofloxacin and equal to that of sparfloxacin. The efficacy of AM-1155 was also equal to that of subcutaneous penicillin G administration at the same dosage.

Human BST-1, a bone marrow stromal cell surface antigen, is a glycosyl-phosphatidylinositol-anchored protein that facilitates the growth of pre-B cells. We report here the molecular cloning of murine BST-1 cDNA. The deduced amino acid sequence of murine BST-1 had 71% similarity with human BST-1 and 30 and 25% similarity with CD38 and Aplysiaadenosine diphosphate-ribosyl cyclase, respectively. Murine BST-1 mRNA was expressed in the bone marrow, spleen and thymus in lymphoid organs, and the lung, kidney and heart in nonlymphoid organs. Restriction fragment length polymorphism (RFLP) was shown in BALB/c, DBA/2 and NZB vs C57BL/6, A/J, CBA/N, NZW, BXSB and MRL/lpr. RFLP was mapped to the 5′ portion of the murine BST-1 gene.

This report describes experiments on friction of Si3N4 and SiC sliding against themselves and against each other in water at room temperature. The friction coefficient of Si3N4 against itself is f = 0.7 at low speeds (0.2 cm/s). At speeds above 6.5 cm/s and 4.91-N load, hydrodynamic lubrication sets in, with f = <0.002 and an estimated water film thickness of 70 nm. Between 0.2 and 5 cm/s, mixed lubrication occurs. This remarkably thin hydrodynamic film is made possible by the tribochemical wear of Si3N4 which occurs by dissolution in water and an absence of wear particles. The friction coefficient of SiC, against SiC or Si3N4 in water at low speeds is f = 0.26. Wear occurs by dissolution and fracture pitting. Small wear particles are observed. The friction coefficient of SiC against SiC is independent of sliding velocity between 0.2 and 20 cm/s. Hydrodynamic lubrication is obtained with a Si3N4 pin on SiC plate near 10 cm/s, mixed lubrication is obtained with a SiC in on Si3N4 plate at v < 20 cm/s.

The friction coefficient of hot-pressed Si3N4 on itself was measured in the temperature range of 150 to 800°C. Sliding occurred in dry argon, dry and humid air and the sliding velocity was varied from 0.1 to 10 cm/s. In dry argon and dry air, the friction coefficient is f = 0.8 ± 0.05 over the whole temperature range and wear occurs by fracture as it does at room temperature.In humid air, the friction coefficient is a complex function of sliding velocity, load, and temperature. Values of as low as f = 0.2 are obtained in a narrow velocity range at temperatures between 150 and 650°C. They are associated with the formation of a soft, amorphous, surface layer of silicon dioxide. At 800° C, the friction coefficient is f = 0.8 in all atmospheres.At every temperature and load, there is a velocity above which the friction coefficient increases rapidly and wear by microfracture is predominant. We speculate that the observed behavior is due to a balance between tribochemical reaction rate and the rate of mechanical wear.

A new complex lipide, phytoglycolipide, has been isolated from soybea, corn, flaxseed, peanut, sunflowerseed, cottonseed, and wheat phosphatides. This material is obtained by a mild alkaline saponification procedure which destroys glycerol-containing lipides. The new lipide constitutes about 5% of the crude phosphatides and is obtained as a white amorphous powder of identical composition, optical activity, and solubility properties from the various sources. Phytoglycolipide gives on hydrolysis phytosphingosine (and, in the case of soybean only, an unsaturated derivative of phytosphingosine) fatty acids, inositol, glucosamine, a hexuronic acid, galactose, arabinose, mannose, and phosphate. Phytoglycolipide is the first sphingolipide of plant origin to be described and is unique among complex sphingolipides in that it has the structural features of a glycolipide and of a phosphatide.

Summary: A new complex lipide, phytoglycolipide, has been isolated from soybea,, corn, flaxseed, peanut, sunflowerseed, cottonseed, and wheat phosphatides. This material is obtained by a mild alkaline saponification procedure which destroys glycerol-containing lipides. The new lipide constitutes about 5% of the crude phosphatides and is obtained as a white amorphous powder of identical composition, optical activity, and solubility properties from the various sources. Phytoglycolipide gives on hydrolysis phytosphingosine (and, in the case of soybean only, an unsaturated derivative of phytosphingosine) fatty acids, inositol, glucosamine, a hexuronic acid, galactose, arabinose, mannose, and phosphate. Phytoglycolipide is the first sphingolipide of plant origin to be described and is unique among complex sphingolipides in that it has the structural features of a glycolipide and of a phosphatide.

1. Plasma 17-hydroxysteroid levels and urinary 17-hydroxysteroid excretion rates were observed in humans before, during, and after the intravenous administration of purified hyperglycemic factor. There were no significant changes in plasma values, but some patients showed elevation in urinary excretion of steroids, apparently related to the degree of stress incurred. 2. By these methods, we could observe no direct action of hyperglycemic factor on the adrenal cortex.

1. Employing the analytical procedure of Nelson and Samuels for plasma 17-hydroxycorticosteroids, it has been shown that the intravenous injection of hydrocortisone in rats produces high concentrations of hormone, followed by a swift return to very low levels. 2. The rapid disappearance of exogenous hydrocortisone from the circulation is prevented by hepatectomy, but nephrectomy and splenectomy exert no appreciable effect.

Laser sources that feature a controlled pulse shape and long-term stability are required in a wide range of scientific fields. We developed a maintenance-free 3D-shaped UV-laser system for the photoinjector (RF gun photocathode) of an X-ray SASE free electron laser (FEL). The laser pulse-energy stability was improved to 0.2%–0.3% (rms, 10 pps, 0.4 TW in femtosecond operation) at the fundamental wavelength and to 0.7%–1.4% at the third-harmonic wavelength. This stability was continuously maintained for five months, 24 hours a day. Such improvement reflects an ability to stabilise the laser system in a humidity-controlled clean room. The pulse-energy stability of a mode-locked femtosecond oscillator was continuously held at 0.3% (p–p) for five months, 24 hours a day. In addition, the ideal spatial and temporal profiles of a shot-by-shot single UV-laser pulse are essential to suppress the emittance of the electron-beam pulse generated by the photocathode of the RF gun. We apply a deformable mirror that automatically shapes the spatial UV-laser profile with a feedback routine, based on a genetic algorithm, and a pulse stacker for temporal shaping at the same time. The 3D shape of the laser pulse is spatially top-hat (flattop) and temporally — a square stacked pulse. We apply the Q-scan method to evaluate the emittance of the electron beam generated by a 3D-shaped laser pulse. By using a 3D-shaped laser pulse of diameter 0.8 mm on the cathode and duration 10 ps (FWHM), we obtain a minimum horizontal normalised emittance of 1.4π mm mrad with beam energy of 26 MeV, holding its net charge to a 0.4 nC pulse-1. At a higher net charge of 1.0 nC pulse-1, the minimum beam emittance is 2.3π mm mrad with equivalent diameter and a longer pulse duration of 20 ps (FWHM). In this study, we demonstrate 3D shaping [both temporal (1D) and spatial (2D)] short pulse (5–20ps) laser beam as an ideal light source for yearlong stable generation of a low emittance electron beam with a high charge (1–2 nC pulse-1). Here, we report the principle and development process of our beam-quality control systems.

The hydrogen storage characteristics and the microstructure of Mg alloys containing 10‐60 wt.% LaNi5are studied.