Construction of mono- and bivalent human single-chain Fv fragments against the D antigen in the Rh blood group: multimerization effect on cell agglutination and application to blood typing

An expression system for mono- and bivalent single-chain Fv fragments (scFv) of a human antibody against D antigen in the Rh blood group system was established in Escherichia coli. The cDNA encoding the Fv fragment of the anti-D monoclonal antibody D10 was cloned using the polymerase chain reaction and expressed in E.coli by fusing with a peptide tag link in the C-terminus of the light chain variable region. The scFv fragment expressed by the bacteria produced specific agglutination of human D positive red cells in the presence of an anti- peptide tag antibody. Flow cytometric analysis clearly indicated that the bacterially prepared scFv showed high specificity and affinity for D antigen, which was identical with that of the parental IgG. In order to construct bivalent D10 scFv for use in direct cell agglutination, the scFv was fused with a dimeric protein, bacterial alkaline phosphatase (BAP). The fusion protein produced significant agglutination of human red blood cells with D antigen, confirming that the bacterially expressed fusion protein is a functional bivalent antibody fragment. Specific agglutination of D positive red cells by D10 scFv-BAP was enhanced in the presence of anti-BAP antibody, suggesting that further multimerization of scFv led to highly efficient cell agglutination. By grafting BAP enzymatic activity into the scFv fragment (enzyme-linked scFv), blood typing could conveniently be performed. These results indicate that bacterially expressed scFv and scFv-BAP would be of practical use in blood typing. The system reported here could also be applied to the examination of other cell surface antigens and cell agglutination.      

Representation of freeform surfaces suitable for optimization

To represent the freeform surface shape, the axially asymmetric quadric and a new set of the orthogonal polynomials are introduced. In this representation, surface tilt, paraxial properties, and higher order surface shape are clearly separated. With this representation, the optimization process can be simple and efficient.     

Novel Approach for the Reduction of ZnO and MgO Using a Direct Diode-Laser

In this work, we present the results of using the diode laser with an energy density of 6.6 × 10¹¹ W/m³ for reducing ZnO to Zn in vacuum as a first step. Subsequently, we use the diode laser for the reduction of MgO using Zn as the reducing agent. Although Zn is one of the candidates proposed for the renewable energy cycle, it is more auspicious to use it as a recyclable reducing agent. Herein, the reduction efficiency was measured in terms of moles of Zn or Mg obtained per moles of ZnO or MgO ablated. The energy efficiency is measured in terms of mass of Zn or Mg produced per energy consumed by diode laser. For the first part, the largest reduction rate was 15.8 mg/s, corresponding to reduction and energy efficiencies of 76.6 pct and 16.14 mg/kJ, respectively. The yield for the process was 8.8 pct of the theoretically calculated one, which is only better than the solar ZnO reduction process. For the second part, the reduction of MgO with Zn was attainable by diode laser, the resultant Mg was associated with Zn traces, and the electron probe micro analysis results showed that the MgO reduction efficiency fluctuates between 14.4 and 26.6 pct. Different scenarios were suggested for the mechanism of the reaction.     

Self‐Assembled Multilayer‐Stabilized Nickel Nanoparticle Catalyst for Ligand‐Free Cross‐Coupling Reactions: in situ Metal Nanoparticle and Nanospace Simultaneous Organization

We have developed a conceptually and methodologically novel self‐assembled multilayer nickel nanoparticle (NP) catalyst – sulfur‐modified gold‐supported Ni NPs (SANi) – for organic synthesis. The SANi catalyst was easily prepared through a three‐step procedure involving simultaneous in situ metal NP and nanospace organization. This unique method does not require any conventional preformed template for immobilizing and stabilizing NPs. SANi catalyzes carbon‐carbon bond‐forming cross‐coupling, Kumada coupling, and Negishi coupling reactions under ligand‐free conditions and can be used repeatedly for these reactions. Physical analysis of SANi showed that the active species in these reactions are self‐assembled multilayer zerovalent Ni NPs with a size of ∼3 nm.

     

臭氧高级氧化组合技术处理垃圾渗滤液达标

分别选取上海某垃圾焚烧厂及填埋场的垃圾渗滤液MBR出水为处理对象,采用臭氧高级氧化(AOP)技术,并结合混凝预处理及生化处理进行小试.结果表明:对于垃圾焚烧厂MBR出水,采用AOP1(O3)/生化/AOP2(O3组合)处理,当总AOP投加量在3～3.5个单位时就可达到COD＜ 100 mg/L的新排放标准;对于垃圾填埋场MBR出水,采用混凝/AOP(O3/H2O2)处理,当AOP投加量为6个单位时就可达到COD＜100 mg/L的排放标准.综合经济性因素,臭氧氧化组合处理工艺[(混凝)/AOP1(O3)/生化/AOP2(O3/H2O2)]为垃圾渗滤液深度处理的最佳方式.     

Construction method of axially asymmetric lenses

A method to find the optimal position of tilt surfaces to construct axially asymmetric lens systems is proposed. The tilt surface number is extended to the real number and included in the independent variables of the optimization.     

Ce³+-induced exopolysaccharide production by Bradyrhizobium sp. MAFF211645

Ce³⁺, a rare earth element (REE), has been widely used in high-technology industries. Despite the importance of Ce³⁺ in the fields of chemistry and physics, the role of Ce³⁺ in biology has been ignored. To investigate physiological effects of Ce³⁺ on microorganisms, we screened microorganisms that showed peculiar growth in the presence of Ce³⁺. We isolated a free-living soil bacterium that produced exopolysaccharide (EPS) around its colonies on 1/100 nutrient agar with 30 μM CeCl₃ or 1.0% d-mannitol. The bacterium was identified as Bradyrhizobium sp. by morphological, biochemical, and physiological tests as well as 16S rDNA sequence analysis. La³⁺, Pr³⁺, and Nd³⁺ also induced EPS production in large quantities, while Sm³⁺ did in small amounts. However, other heavier REEs from Eu³⁺ to Lu³⁺, and metals such as Na⁺, Al³⁺, K⁺, Ca²⁺, V³⁺, Cr³⁺, Co²⁺, Ni²⁺, Sr²⁺, Ba²⁺, and Pb²⁺ did not induce EPS production. The mean molecular weight of EPS was estimated to be approximately 1 × 10⁶ by Sepharose CL-4B column chromatography. TLC revealed that EPS was composed of l-rhamnose. Quantitative analysis of alditol acetate derivatives of acid hydrolyzate of EPS by GLC revealed that EPS was composed of more than 95% l-rhamnose, indicating that this EPS was a rhamnan. The spectrum of FT-IR of the rhamnan demonstrated that l-rhamnose residues in the rhamnan were α-linked. GC/MS analysis of methylated alditol acetate derivatives of the rhamnan demonstrated that it was composed of main chain α-(1→4)-linked l-rhamnopyranosyl residues. From spectral analyses of ¹H-NMR and FT-IR, EPS produced in the presence of 1.0% d-mannitol was found to be structurally similar to rhamnans.     

Power differential method for discrimination between fault andmagnetizing inrush current in transformers

To avoid the needless trip by magnetizing inrush current, the second harmonic component is commonly used for the blocking differential relay in power transformers. However, the second harmonic component in fault current is increased by the introduction of underground 500 kV lines. This paper describes a new method to discriminate internal fault from inrush current by the sum of active power flowing into transformers from each terminal. The average power is almost zero for energizing, but an internal fault consumes large power. To check the performance of this method, actual inrush current and voltage waveforms of a 500/154 kV transformer are accurately measured by digital equipment. The usefulness is confirmed by applying the method to the measured inrush and simulated fault data     

Beta-adrenoceptor stimulation-mediated preconditioning-like cardioprotection in perfused rat hearts

The metabolic rates of six female grey seal (Halichoerus grypus) pups were measured during their postweaning fast at air temperatures between -15 degrees and 30 degrees C. The composite of their individual thermal neutral zones extended from a mean lower critical temperature of -7.1 degrees +/- 0.7 degree C to a mean upper critical temperature of 23.0 degrees +/- 0.4 degree C. Within the thermal neutral zone, mean standard metabolic rate of the fasting animals was 1,265 +/- 82 kcal d-1, or about 1.1 times the value predicted for an adult animal of similar body mass (mean mass = 40.9 +/- 1.2 kg). For those grey seal populations that reproduce during winter months in the eastern and western Atlantic and in the Baltic Sea, the lower critical temperature of fasting pups corresponds closely with the coldest mean monthly air temperature at the northern end of their breeding ranges. This observation supports the hypothesis that cold ambient air temperatures limit the northern breeding distribution of grey seals, primarily through their thermoregulatory effects on small, fasting pups before they enter the water.