[Observation for 3 years on the immune effects of hepatitis B vaccine in susceptible population]

Chinese-produced HB vaccine induced high levels of antibodies against HB surface antigen in susceptible population (babies born to mothers who were negative for HBsAg and people who were negative for all the HBV markers). Eight months after the first dose, 97.73 and 93.75 percent of the neonates who received 10 micrograms (group I) and 20 micrograms (group II) vaccines and 92.45 percent of the adults who received 20 micrograms vaccine (group III) developed anti-HBs with the S/N values of 42.12, 46.53 and 36.20, and gave effective protection rates (S/N greater than or equal to 10) of 86.36%, 89.58% and 79.25%, respectively. No significant difference was noted between these groups. After three years, the positive rates and the S/N values of anti-HBs were 17.1% and 3.70 in group I, 15.6% and 4.23 in group II, 20.4% and 4.04 in group III respectively. One month after booster injection in anti-HBs, the S/N values of anti-HBs were 85.12 in group I with 10 micrograms vaccine, 89.23 in group II with 30 micrograms vaccine and 90.82 in those aged 4-10 years with 10 micrograms vaccine. The infection rate in the neonates who were not vaccinated with HB vaccines (11.11%) was higher than those who were vaccinated (0%). So it is clear that Chinese-produced HB vaccines are safe and effective.

[Effects of alcohol extract from Polygonatum odoratum (Mill.) Druce and Cuscuta australis R. Br. on immunological function of mice injured by burns]

This paper shows that the alcoholic extract from Polygonatum odoratum and Cuscuta australis increases the percentage of phagocytosis and the index of phagocytosis of macrophages as well as hemolysin and proliferation of lymphocytes up to normal level in mice with II+ burn injury covering 5% body surface. It follows that both Polygonatum odoratum and Cuscuta australis may serve as a kind of immunopotentiator for mammals.

Generation of dark solitons under a cw background using waveguide electro-optic modulators

We propose a novel method for generating dark solitons with a cw background by using broadband guided-wave electro-optic modulators. The generated pulse can be amplified by stimulated Raman scattering to permit the observation of soliton effects in the fiber.

Hb Hekinan observed in three Chinese from Macau; identification of the GAG----GAT mutation in the alpha 1-globin gene

Hb Hekinan, an alpha chain variant that is characterized by a Glu----Asp mutation at position alpha 27, was observed in three Chinese females attending a prenatal clinic in Macau. The relative quantities of the stable hemoglobin were 13-14% (average 13.3%); its identification was greatly aided by the separation and purification of the peptides by reversed phase high performance liquid chromatography. Dot-blot analysis of amplified DNA with 32P-labeled probes located the mutation in codon 27 of the minor alpha 1-globin gene; the change involved a GAG (coding for glutamic acid) to GAT (coding for aspartic acid) mutation.

Interactions between dark solitons

The interaction forces between two dark solitons are numerically investigated. It is found that dark solitons are less affected than bright solitons by their respective interaction forces. An empirical expression for the separation of two solitons as a function of initial separation and traveling distance is deduced, which agrees well with numerical results.

Periodic amplification of dark solitons using stimulated Raman scattering

The possibility of periodically amplifying dark solitons in a normally dispersive optical fiber is studied. It is found that, as with bright solitons, an all-optical, repeaterless, and stable system for dark-soliton transmission at a rate of 20 GHz over thousands of kilometers in a lossy fiber is achievable, if periodic amplification using stimulated Raman scattering is incorporated.

Propagation properties of dark solitons

We numerically study the initial-value problem of the nonlinear Schrödinger equation in the normal-dispersion regime of an optical fiber. A nonchirped hyperbolic tangent input pulse having arbitrary amplitude is found to evolve into a primary dark soliton having a constant amplitude and speed. The effect of the input amplitude is to alter the pulse width of the primary dark soliton. In addition, a set of secondary dark solitons of smaller amplitude moving away from the primary pulse is also generated. It is also shown that nonlinear dark pulses in optical fibers are more stable than bright pulses with respect to loss and noise.

The relationship between Hb Bart's levels in cord blood and the deletions of alpha-globin genes

A relationship between Hb Bart's levels in cord blood and the number of alpha-globin genes has been established by screening cord blood samples from 1,075 newborn babies. Diagnosis was made by gene mapping of DNA samples with restriction endonuclease digestion. The presence of Hb Bart's was determined with a discontinuous microelectrophoresis on cellulose acetate at pH 8.34. The establishment of this relationship allows an early diagnosis of alpha-thalassemia by this simple microelectrophoretic procedure.

Evolution of femtosecond pulses in single-mode fibers having higher-order nonlinearity and dispersion

Using computer simulations, we examine the effects of higher-order dispersive and nonlinear propagation processes on the spectral and time development of ultrashort, high-intensity pulses propagating in single-mode optical fibers having normal dispersion. Our results indicate that both the cubic-dispersion term and the shock term of the nonlinear Schrödinger equation contribute to asymmetry in the pulse power spectrum and cause highly nonlinear chirp.

Two cDNA clones coding for the legumin protein of Pisum sativum L. contain sequence repeats

The sequence of two cDNA clones coding for the whole of the β-subunit and most of the α-subunit of legumin are presented together with a considerable amount of protein sequence data to confirm the predicted amino acid sequence. A unique feature shown by these cDNAs is the presence of three 56 base pair tandem repeats in the region encoding the C terminal of the α polypeptide. The tandem repeats are also exhibited in the predicted polypeptide sequence as three 18 amino acid repeats which contain extremely high proportions of polar, mainly acidic, residues. The new sequences are compared to the previously published sequence of some shorter legumin cDNAs (Nature 295: 76-79). In the region where the sequences overlap, the previous cDNAs differ from the new ones by only a few base substitutions but most of the repeated region is not present though the sequences on either side are. The possibility that the absence of the repeats may reflect the difference between two types of legumin gene, rather than an artefact of the cloning of the cDNAs, is discussed.