Time domain analysis of patch antennas in a magnetized plasma bythe spatial network method

The near field of a patch antenna in a magnetized plasma is simulated by use of the spatial network method, which is a three-dimensional time domain simulation method. Two fundamental cases are examined in the radiated field: where the direction of the constant magnetic field is perpendicular to the patch plane, and where it is parallel. Results show that radiation characteristics of patch antennas in a magnetized plasma are different from those in free space. It was also confirmed that the Faraday effect is shown in the near field when a perpendicular constant magnetic field is applied to the antenna. In this analysis, the free boundary condition is approximated by terminating the volume with the free space characteristic impedance. A stricter model is necessary, if a reflectionless boundary is to be realized     

Inhibitory effect of glucocorticoids on depigmentation of melanosome in cultured embryonic chick pigment retina

A material of flies collected in two localities (altitude of 3900 and 4500 m) in the Barun Khola Valley (East Nepal) was studied, representing the early spring aspect of the species composition of flies. Of the total number of 2309 fly specimens 99.3% represented two species of the genus Paregle (P. aterrima, P. sp.); both are autochthonous high altitude hemisynanthrophic forms. The remainining 0.7% represent 9 species, most of which are more or less eurytopic species of palearctic or holoarctic distribution (Calliphora vicina, C. vomitoria, Meoneura flavifacies, Scatophaga stercoraria, Hydrotea hirticeps, Orthellia caesarian, Paregle danieli, Anthomyiidae g. sp. 1, g. sp. 2).     

Coagulase-negative staphylococci in conjunctivitis and blepharitis

Coagulase-negative staphylococcus (C-NS) are regarded as normal flora of the lids and conjunctiva. The ability of these organisms to cause conjunctivitis and blepharitis can be overlooked or disregarded. To elucidate the role of individual C-NS species in these eye diseases we compared Staphylococcus sp. isolated from the conjunctiva and lids of 50 healthy volunteers with 248 strains of Staphylococcus isolated from patients with staphylococcal conjunctivitis or blepharitis. S. epidermidis was the most frequent species isolated from the conjunctiva and lids of both groups. S. aureus was isolated only from infected patients. No individual C-NS species was found to be significantly associated with eye disease, but the colony count of C-NS after isolation was a useful indicator of conjunctivitis and blepharitis. The ability of Staphylococcus to ferment mannitol or mannose was associated with isolates only from infected patients.     

Comparison of two rapid urease tests for detection of Helicobacter pylori infection

The selection of NIH 3T3 cells expressing a hydroxytamoxifen-inducible c-Raf-1-estrogen receptor fusion protein (c-Raf-1-BxB-ER) in the absence or presence of the inducer results in dramatic differences in the expression levels of the fusion protein. Hydroxytamoxifen-mediated constitutive activation of the Raf signal favors the selection of cells expressing low levels of c-Raf-1-BxB-ER. Cells selected in the absence of hydroxytamoxifen express up to 20 times higher levels of the inducible Raf kinase. Activation of the oncogenic Raf kinase in cells expressing low levels leads to a weak activation of the Raf/Mek/Erk cascade and the induction of S phase in confluent cells. The activation of cells expressing high levels of the kinase leads to a strong persistent signal and inhibits DNA synthesis and mitosis in proliferating cells. The inhibition of DNA synthesis and cell division is presumably due to the elevated expression of the cyclin-dependent kinase inhibitor p21cip1, similar to cells exposed to ionizing radiation. Despite the inhibition of DNA synthesis and mitosis, the constitutive activity of the Raf signaling pathway is still able to initiate cell growth. Activation of the high-intensity Raf signal in arrested serum-starved cells induces cell growth up to a size corresponding to that of M-phase cells in the absence of DNA synthesis. High-intensity Raf signals in proliferating cells consistently lead to an accumulation of cells with the size of M-phase cells and the DNA content of G1 cells or G2-M-phase cells. Therefore, the activation of Raf kinase is sufficient to drive cell growth, even in the presence of high levels of the cyclin-dependent kinase inhibitor p21cip1.     

Synchronization of the factors critical for diabetic teratogenesis: an in vitro model

OBJECTIVE: Our goal was to determine the relationship between critical factors and conditions such as gestational age and exposure time to elevated glucose levels in diabetic embryopathy. STUDY DESIGN: A postimplantation rat embryo culture was used as a model for investigation. The effect of various factors on embryonic development was studied. Experiments were conducted with increasing glucose concentrations (150 to 905 mg/dl, n = 186), at various gestational ages (10 to 12 days, n = 169), and for varying durations of exposure (30 to 180 minutes, n = 169). Gross morphologic characteristics of the yolk sac and embryo were assessed. RESULTS: Embryopathy was induced by hyperglycemia in a dose-related fashion: a 20% rate at two times control glucose concentration, almost a 50% rate at four times control, and approximately a 100% abnormality rate at more than six times control. A critical window in gestational age, days 10 to 11, and a minimum exposure time to hyperglycemia of 2 hours were necessary to induce teratogenesis. CONCLUSIONS: Diabetic teratogenesis occurs in a dose-related fashion and requires a minimum exposure time and critical gestational age. Only synchronization of these critical conditions induces embryonic maldevelopment. Furthermore, nonsynchronized aberrant conditions may result in apparently normal embryonic development.     

PMD characteristics of twisted photonic crystal fibre

A photonic crystal fibre (PCF) with polarisation mode dispersion (PMD) of 0.03 ps/rkm was obtained by unidirectional twist. The work was also successful in reducing the PMD of the PCF to 10% of its initial value by periodic bidirectional twisting without loss increasing and structural deformation.     

对确定燃用不同燃料加热炉炉膛高度的探讨

通过不同燃料每单位热量应有的废气量的不同及废气黑度的不同，对燃用不同燃料的加热炉的炉膛高度进行了综合排序，供加热炉设计或改造时确定炉膛高度时参考。     

Raman amplification characteristics at 850 nm in a silica-based photonic crystal fiber

We achieve a 2.5-dB improvement in the power penalty in a 10-Gb/s-based distributed Raman amplification transmission at 850 nm using a silica-based low-loss photonic crystal fiber (PCF). The experimental results agree well with a signal-to-noise ratio improvement model. The model indicates the negligible influence of double Rayleigh backscattering in the fabricated PCF.