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The thermal lens problem of optical system caused by high temperature environment is a common problem. Athermal design of lenses based on optical calculation software is an effective passive compensation method. But it is difficult to determine its accuracy and measure it experimentally. We describe an athermal design technology and propose a simulated scheme to verify the accuracy of this design. Three materials with negative dn/dT have been selected to compensate for the thermal lenses produced by a fused silica lens. The results show that the compensation effect of N-PSK53A is the best.

Optical lenses used in high temperature environment are usually affected by thermal lenses problems, but it is difficult to evaluate their focal shifts in practical applications. A three-dimensional single-lens model based on finite element solver was built to evaluate the focal shift in this study, when the temperature of surface was raised from the initial temperature to the specified temperature. An experimental method based on a Hartmann-Shack wavefront sensor was proposed to verify the rationality of the model. The nearly same results between simulations and experiments for N-BK7 and fused silica were obtained, which proves that it is feasible to analyze focal shifts of optical lenses by simulation methods.

A two-step dual-label TRFIA was developed for the simultaneous detection of human epididymis protein-4 and cancer antigen 125 in a single run. The performance of this assay was first evaluated using clinical serum samples, and then compared with commercialized kits. The sensitivity of this assay for cancer antigen 125 detection was 0.5 U/mL (dynamic range, 0-1400 U/L), and the sensitivity for human epididymis protein-4 detection was 1 pM (dynamic range, 1-900 pM). High correlation coefficients (R) were obtained between the present dual-label TRFIA and commercially available kits (R = 0.99). The present dual-label TRFIA has high sensitivity, specificity, and accuracy in clinical sample analysis. It is a good alternative to the single-label diagnostic methods.

Bladder cancer is a heterogeneous disease and occupies highest incidence in developed country. Time-resolved fluoroimmunoassays (TRFIA) is a new detection technique with a feature of sensitive, simple and inexpensive. The aim of this study is to establish a dual-label TRFIA for the simultaneous detection of BLCA-4 and NMP52 in urine in a single run. The sandwich immunoassay was used to detect the concentration of BLCA-4 and NMP52 in urine. BLCA- 4 and NMP52 in urine were captured by anti-BLCA-4 and anti-NMP52 antibodies immobilized on microtiter wells, and then banded together with another anti-BLCA-4 and anti-NMP52 labeled with europium(III) Sm3+ and samarium(III) Eu3+ chelates, followed by fluorescence measurement using time resolved fluorometry. To assess the performance of this assay, clinical urine samples were used, and then commercialized kits were compared. The sensitivity for BLCA-4 and NMP52 detection of this assay were 2 U/mL (dynamic range, 5-300 U/L) and 1 μg/ml (dynamic range, 2-150 μg/ml) respectively. The correlation coefficients (R) between the present dual-label TRFIA and commercially available kits were high. R-values were 0.99 for BLCA-4 and NMP52. The cross-reactivity seems not to influence the results. The present dual-label TRFIA, allowing the simultaneous detection ofBLCA-4 and NMP52, has high sensitivity, specificity, and accuracy in clinical sample analysis. Therefore, it has good prospects of application.

The dominant microalgal species, quantity of heterotrophic bacteria and Vibrio in the intestines and gills of Litopenaeus vannamei (Pacific white shrimp), positive detection rate of white spot syndrome virus (WSSV), and water quality indices were investigated at the final culture stage (88th day in culture season). Correlation of microalgal community, bacteria quantity, and shrimp production were analyzed by statistical analysis methods. Every 10 days, probiotics were used in groups A, B, and C, consisting of Bacillus, photosynthetic bacteria (PSB), and equal parts Bacillus and PSB, respectively. The results showed that production (25597.33 ± 928.46 kg ha−1) and survival rate (77.06 ± 9.00 %) was the highest in group C, but positive detection rate of WSSV was the lowest. The microalgal community of group C was significantly dominated by Chlorella pyrenoidosa, with an average density and dominance of (289.52 ± 142.10) × 107 cells L−1 and 0.878 ± 0.161, respectively. The correlation analysis indicated a significant negative correlation between Cyanophyta dominance and shrimp production (P 0.05). Accordingly, microalgal dominant species should be controlled as a key factor in the shrimp culture season; in particular, the dominance of Cyanophyta should be restricted to a low level. Meanwhile, the combined use of Bacillus and PSB probiotics was considered an effective solution to optimize microalgal communities and controlling the cell density of Cyanophyta.

The reduction of geraniol to citronellol is the first step for the synthesis of natural phytol in the production of tocopherols and natural vitamin K. Baker’s yeast was used in the bioreduction described above as a whole-cell biocatalyst. However, the enzyme responsible for the reduction of geraniol to citronellol is not yet known. Four old yellow enzyme (OYE) genes were cloned from yeast and plants, and expressed in Escherichia coli for a high level of recombinant proteins. The recombinant protein displayed a catalytic activity of converting geraniol to citronellol as a sole product verified by GC-MS analyses. The recombinant OYE2 intact cells were found to show 3.7 and 1.9-fold higher activity than that of yeast cells and the recombinant crude extracts, respectively. Compared to the recombinant fusion enzyme, the entrokinase-cleaved enzyme displayed nearly identical activity for geraniol reduction. To our knowledge, this is the first enzyme identified to catalyze the formation of citronellol from geraniol by reducing the allylic alcohol double bond, which is normally known as inactivating group for the old yellow enzymes. Electronic Supplementary Material Supplementary material is available for this article at 10.1007/s13659-011-0032-6 and is accessible for authorized users.

EAFP2 is a novel antifungal protein isolated from the bark of the tree Eucommia ulmoides Oliver. It consists of 41 residues and is characterized with a five-disulfide motif and the inhibitory effects on the growth of both cell wall chitin-containing and chitin-free fungi. The crystal structure of EAFP2 at an atomic resolution of 0.84 Angstrom has been determined by using Shake-and-Bake direct methods with the program SnB. The phases obtained were of sufficient quality to permit the initial model built automatically and the structural refinement carried out using anisotropic displacement parameters resulted in a final crystallographic R factor of 6.8%. In the resulting structural model, all non-hydrogen protein atoms including an unusual pyroglutamyl acid residue at the N-terminal can fit to the articulated electron densities with one centre and more than 65% of the hydrogen atoms in the protein can be observed as individual peaks in the difference map. The general fold of EAFP2 is composed of a 3(10) helix (Cys3-Arg6), an alpha-helix (Ala27-Cys31) and a three-stranded antiparallel beta-sheet (Cys16-Ser18, Cys23-Ser25, and Cys35-Cys37) and cross-linked by five disulfide bridges. The tertiary structure of EAFP2 can be divided into two structural sectors, A and B. Sector A composed of residues 11-30 adopts a conformation similar to the chitin-binding domain in the hevein-like proteins and features a hydrophobic surface embraced a chitin-binding site (Tyr20, 22, 29, and Ser18). The distinct disulfide bridge Cys7-Cys37 connects the N-terminal ten residues with the C-terminal segment 35-41 to form the sector B, which features a cationic surface distributing all four positively charged residues, Arg6, 9, 36, and 40. Based on these structural features, the possible structural basis of the functional properties of EAFP2 is discussed. (C) 2004 Elsevier Inc. All rights reserved.

Two antifungal proteins, named Eucommia antifungal peptides 1 and 2 (EAFP1 and EAFP2), have been purified from the bark of the tree E. ulmoides Oliver and show a relatively broad spectrum of antifungal activity against several agriculturally important plant pathogens. One of these small proteins (EAFP2) has been crystallized. The crystal belongs to space group P2(1), with unit-cell parameters a = 19.01, b = 23.16, c = 30.69 Angstrom, beta = 98.54degrees. 1.0 Angstrom resolution data were collected from an EAFP2 crystal and have been used to obtain phase information directly by an ab initio method.

Two antifungal peptides, named EAFP1 and EAFP2, have been purified from the bark of Eucommia ulmoides Oliv. Each of the sequences consists of 41 residues with a N-terminal blockage by pyroglutamic acid determined by automated Edman degradation in combination with the tandem mass spectroscopy and the C-terminal ladder sequencing analysis. The primary structurs all contain 10 cysteines, which are cross-linked to form five disulfide bridges with a pairing pattern (C1-C5, C2-C9, C3-C6, C4-C7, C8-C10). This is the first finding of a plant antifungal peptide with a five-disulfide motif. EAFP1 and EAFP2 show characteristics of hevein domain and exhibit chitin-binding properties similar to the previously identified hevein-like peptides. They exhibit relatively broad spectra of antifungal activities against eight pathogenic fungi from cotton, wheat, potato, tomato and tobacco. The inhibition activity of EAFP1 and EAFP2 can be effective on both chitin-containing and chitin-free fungi. The values of IC50 range from 35 to 155 mug/ml for EAFP1 and 18 to 109 mug/ml for EAFP2. Their antifungal effects are strongly antagonized by calcium ions. (C) 2002 Published by Elsevier Science B.V. on behalf of the Federation of European Biochemical Societies.