Features of the volume change and a new constitutive equation of hydrogels under uniaxial compression.

For high-water content hydrogels in compression, the water inside of hydrogels contributes to the response of hydrogels to external loads directly, but part of the water is expelled from hydrogels in the meantime to change the volume of the hydrogel and reduce the contribution. In order to consider the contribution of the water in the constitution equation, PVA (polyvinyl alcohol) hydrogels with high-water content were used as examples, and compressive experiments were carried out to measure both the stress-strain relation and the change of the volume in the meantime. By considering the effect of the difference of the contribution of water in different directions of the hydrogel, we deduced a new constitutive equation, which can pretty well depict the stress-strain of hydrogels with different water contents. The results showed that the contribution of water to the total stress increases with the compression strain and even exceed that of the polymer, although the expelled water reduces the contribution at the early loading stage, which well explains the difference of elastic moduli of hydrogels in compression and tension.

Two-qubit conditional phase gate in laser-excited semiconductor quantum dots using the quantum Zeno effect.

We propose a scheme for a two-qubit conditional quantum Zeno phase gate for semiconductor quantum dots. The proposed system consists of two charged dots and one ancillary neutral dot driven by a laser pulse tuned to the exciton resonance. The primary decoherence mechanism is phonon-assisted exciton relaxation, which can be viewed as continuous monitoring by the environment. Because of the Zeno effect, a strong possibility of emission is sufficient to strongly modify the coherent dynamics, with negligible probability of actual emission. We solve analytically the master equation and simulate the dynamics of the system using a realistic set of parameters. In contrast to standard schemes, larger phonon relaxation rates increase the fidelity of the operations.

[Experimental and clinical study of shuanghuanglian aerosol in treating acute respiratory tract infection].

Two hundrde and two cases of acute respiratory tract infection (ARI) were treated with Shuanghuanglian (SHL) aerosol. In these cases, the majority of cases were virus infection and 64% of them was caused by the respiratory syncytial virus (RSV). The virostatic and bacteriostatic test were done in vitro by the cell culture method and it was shown that SHL could inhibit the RSV, para-influenza I-IV and 23 kinds of pathogenic bacteria such as Staphylococcus aureus etc. The bacteriostatic effect was positively correlated to the SHL concentration. Experimental study showed that SHL could enhance the NK cell activity, promote the production of alpha-interferon and raise the rate of lymphocyte transformation. The controlled observation on SHL preparation with various dosage-forms revealed that the SHL aerosol in treating early ARI showed better results than that of injections and oral liquor symptomatologically (P < 0.01). The effective rate was 96%.

[Pharmacodynamics and clinical therapeutic effects of aerosol and injection of shuanghuanglian].

The results show that both aerosol and injection of shuanghuanglian can increase the activity of NK cells in peripheral blood of the human body as well as the ability of lymphocyte to produce alpha-interferon. Their broad-spectrum antiseptic and virus-inhibiting actions have also been confirmed. The absolute bioavailability of aerosol was 96.88% (baicalin) and 90.69% (chlorogeniacid). The significant response rate of aerosol and injection was 84% and 83% respectively. The total response rate was 92% and 93% respectively.

[Analysis of proteins and antigens in nine strains of Toxoplasma gondii by means of SDS-PAGE and immunoblotting].

The proteins and antigens of nine strains of Toxoplasma gondii were analyzed by SDS-PAGE and immunoblotting. These strains including RH strain, Zs-2 strain, CN strain and SH1, SH2, SH3, SH4, SH5, SH8 strains, were obtained from other laboratories or isolated from deformity fetus in our laboratory. SDS-PAGE analysis revealed that these strains were very close in the major bands of proteins and differences were observed only in part. There were common components in antigens of all strains using IgG antibody prepared from high-titre rabbit antisera raised against RH strain of Toxoplasma.

[Detection of circulating antigen in urine from mice infected with Toxoplasma tachyzoites].

Urine samples collected from three groups of mice infected experimentally with different numbers doses of Toxoplasma trophozoites were detected for the presence of Toxoplasma circulating antigen by using fast ELISA. The results showed that presence of circulating antigen in all three infected groups of mice in comparison with the normal control group. Toxoplasma circulating antigen was detected on days 5, 4 and 3 after infection in light-, moderate- and heavy-infection groups, respectively. The concentration of circulating antigen was on a parallel with the duration of infection. Western blot analysis of the Toxoplasma circulating antigen in urine revealed the existence of seven specific bands with molecular weights of 75, 67, 55, 43, 30, 28 and 22 kDa.

Construction of a genomic DNA library of the Toxoplasma gondii ZS2 strain, screening of specific clones, and DNA diagnosis of toxoplasmosis.

We have constructed a genomic DNA library of the Toxoplasma gondii ZS2 strain and isolated a specific cloned DNA sequence from this organism. The restriction map of this cloned 1.1-kb DNA fragment was analyzed. Southern and dot-blot analyses showed that the 32P-labeled DNA fragment hybridized to parasite DNA, to DNAs from peripheral blood leukocytes and the thymus of baby pigs that were artificially infected with T. gondii, and to DNAs of T. gondii-positive anencephalic and hydrocephalic fetuses. It did not hybridize with DNA from controls, (i.e., normal human and baby pig peripheral blood leukocytes, spleen of normal mice, Plasmodium falciparum, Pneumocystis carinii, and pBR322). As few as 100 T. gondii parasites or 500 pg of purified DNA from T. gondii can be detected by dot-blot hybridization. This probe method was specific and sensitive, and has been used successfully in detecting various clinical cases of toxoplasmosis with T. gondii.

[Diagnosis of toxoplasmosis by polymerase chain reaction].

Based on the partial sequences of the specific DNA cloned fragment from T. gondii (ZS2 strain) a specific primer of the oligonucleotide for the Toxoplasma gondii DNA sequence has been designed and synthesized in our laboratory. The method of the DNA diagnosis for toxoplasmosis by polymerase chain reaction (PCR) has been established. A specific amplified band was shown in the PCR products from DNAs of T. gondii and seven manifold terata. The DNAs from the peripheral blood leukocytes of fifty normal individuals and seventy-five patients as infants with hepatitis syndrome and pregnant women with previous abnormal birth histories were diagnosed by PCR. Among the seventy-five diagnosed cases, ten were positive. The normal individuals all were negative. Using 32P-cloned T. gondii specific DNA fragment as probe and Southern blot assay, the results showed that the probe only hybridized to the specific amplified DNA bands, but did not hybridize to the amplified DNA products of negative cases. Our PCR method is a rapid, highly specific and sensitive one for detecting toxoplasmosis as compared with DNA probing, immunoassay and animal inoculation.

[Construction of a genomic DNA library of Toxoplasma gondii (ZS2 strain), screening of specific clone and DNA diagnosis of toxoplasmosis].

We have constructed a genomic DNA library of Toxoplasma gondii (ZS2 strain) and screened out a specific DNA sequence for T. gondii. The restriction map of the cloned DNA fragment (1.1kb) was analysed. The Southern and dot-blot analyses showed that the 32P-labeled cloned DNA fragment hybridized to the parasite DNA, DNAs from peripheral white blood cells and thymus of baby pigs artificially infected with T. gondii and DNAs of T. gondii- positive anencephalus and hydrocephalus, but did not hybridize to DNAs from controls, i. e., normal human and baby pig peripheral white blood cells, spleen of normal mouse, Plasmodium falciparum, Pneumocystis carinii and pBR322. As few as 100 T. gondii parasites or 500pg purified DNA from T. gondii can be detected by dot blot hybridization. This established DNA probe method was specific and sensitive and has been successfully used in detecting various cases infected with T. gondii.