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Liposome-based immunoassay (LIA) is an attractive protocol for amplifying the detection signals because of the excellent ability of liposomes to encapsulate signal marker compounds. The antigen-binding activity of the conjugated antibodies on the liposomal surface is crucial for the specificity and sensitivity of LIA. We present here a general platform to ensure that antibodies can conjugate onto the surface of liposomes in a site-specific and oriented manner. A His-handle-modified antibody with Fc region-specific and covalent conjugation was first fabricated using a photoactivatable ZBpa-His tag that was engineered using the aminoacyl-tRNA synthetase/suppressor tRNA technique. Based on the high affinity between the His tag and divalent metal ions, the novel His-modified antibody was oriented onto the surface of nickel ion-modified liposomes encapsulating horseradish peroxidase. With the prostate-specific antigen as a model, the detection efficiency of the new immunoliposomes was evaluated by chemiluminescence immunoassay. The immunoliposomes exhibited a limit of detection of 0.2 pg mL−1, which was a six time improvement compared with that of the chemical-coupled antibody–liposome conjugates. Thus, the proposed immunoliposomes are expected to hold potential applications for the sensitive detection of various biomarkers in complicated serum samples.

Immobilized antibodies with site-specific, oriented, and covalent pattern are of great significance to improve the sensitivity of solid-phase immunoassay. Here, we developed a novel antibody conjugation strategy that can immobilize antibodies in a directional and covalent manner. In this study, an IgG-Fc binding protein (Z domain) carrying a site-specific photo-crosslinker, p-benzoyl-L-phenylalanine, and a single C-terminal cysteine (Cys) handle was genetically engineered. Upon UV irradiation, the chimeric protein enables the Cys handle to couple with the native antibody in Fc-specific and covalent conjugation pattern, resulting in a novel thiolated antibody. Thus, an approach for the covalent, directional immobilization of antibodies to maleimide-modified magnetic nanoparticles (MNPs) was developed on the basis of the crosslinking between sulfhydryl and maleimide groups. The antibody-conjugated MNPs were applied in MNP-based enzyme-linked immunosorbent assay (ELISA) for the detection of carcinoembryonic antigen. The MNP-based ELISA presented a quantification linear range of 0.1–100 ng mL−1 and detection limit of 0.02 ng mL−1, which was approximately 100 times more sensitive than the traditional microplate ELISA (2.0 ng mL−1). Thus, the proposed antibody immobilization approach can be used in surface functionalization for the sensitive detection of various biomarkers.

Enterokinase (EK) is one of the most popular enzymes for the in vitro cleavage of fusion proteins due to its high degree of specificity for the amino-acid sequence (Asp)4-Lys. Enzyme reusability is desirable for reducing operating costs and facilitating the industrial application of EK. In this work, we report the controlled, site-specific and covalent cross-linking of an engineered EKLC on amine-modified magnetic nanoparticles (NH2-MNPs) via microbial transglutaminase-catalyzed bioconjugation for the development of the oriented-immobilized enzyme, namely, EKLC@NH2-MNP biocatalyst. Upon the site-specific immobilization, approximately 90% EKLC enzymatic activity was retained, and the biocatalyst exhibited more than 85% of initial enzymatic activity regardless of storage or reusable stability over a month. The EKLC@NH2-MNP biocatalyst was further applied to remove the His tag-(Asp)4-Lys fusion partner from the His tag-(Asp)4-Lys-(GLP-1)3 substrate fusion protein, result suggested the EKLC@NH2-MNP possessed remarkable reusability, without a significant decrease of enzymatic activity over 10 cycles (P > 0.05). Supported by the unique properties of MNPs, the proposed EKLC@NH2-MNP biocatalyst is expected to promote the economical utilization of enterokinase in fusion protein cleavage.

Ochratoxin A (OTA) is a common food contaminant that seriously threatens the safety and health of consumers. Here, an indirect competitive biotin-streptavidin-amplified enzyme-linked immunosorbent assay (icBA-ELISA) was developed for the sensitive detection of OTA by employing Fc-specific multi-biotinylated antibodies. An Fc-binding protein (Z-domain) carrying a photo-cross-linker (p-benzoylphenylalanine, Bpa) fused with tandem AviTag repeats, viz. ZBpa-(AviTag)n, was first constructed using the aminoacyl-tRNA synthetase/suppressor tRNA technique. Biotin molecules were covalently conjugated to antibodies mediated by the photoreactive biotinylated ZBpa-(AviTag)n, resulting in the Fc-specific multi-biotinylated antibodies (IgG−*Z-Bn conjugates) that were used to establish icBA-ELISA. Among the IgG−*Z-Bn-based icBA-ELISA, the IgG−*Z-B5 conjugates exhibited a half-maximal inhibitory concentration of 0.0519 ng mL−1 and a limit of detection of 0.00944 ng mL−1 for OTA. The sensitivity was improved 4.8 and 4.7 times compared with that of the chemical-coupled IgG−biotin conjugates. Thus, the proposed icBA-ELISA for the sensitive detection of OTA has remarkable potential applications for the detection of various toxins in food.

Fluorophore-antibody conjugates with high photobleaching resistance, high chemical stability, and Fc-specific attachment is a great advantage for immunofluorescence imaging. Here, an Fc-binding protein (Z-domain) carrying a photo-cross-linker (p-benzoylphenylalanine, Bpa) fused with enhanced green fluorescent protein (EGFP), namely photoactivatable ZBpa-EGFP recombinant, was directly generated using the aminoacyl-tRNA synthetase/suppressor tRNA technique without any further modification. By employing the photoactivatable ZBpa-EGFP, an optimal approach was successfully developed which enabled EGFP to site-selectively and covalently attach to native antibody (IgG) with approximately 90% conjugation efficiency. After characterizing the Fc-specific and covalent manner of the EGFP-photoconjugated antibody, its excellent photobleaching resistance for immunofluorescence imaging was demonstrated in a model study by monitoring the toll-like receptor 4 (TLR4) expression in HepG2 cells. The proposed approach here for the preparation of a novel fluorescent antibody is available and reliable, which would play an important role in fluorescence immunoassay, and is expected to be extended to the generation of other biomolecule-photoconjugated antibodies, such as other fluorescent proteins for multiplex immunofluorescence imaging or reporter enzymes for highly sensitive enzyme immunoassays.Graphical abstract.

As a representation of metallic transition metal oxide, MoO2 has drawn great attention for its synthesis and application. Herein, MoO2 microspheres with rough surface have been synthesized from MoO3 microrods via a facile solvothermal method for the first time. The structure and morphology of the as-synthesized MoO2 microspheres are characterized, and it has found that the produced MoO2 microspheres have a typical monoclinic structure with a good single-crystalline property. In addition, the obtained MoO2 microspheres with diameters ranging from 0.5 to 2 μm feature with a rough surface characteristic. Comparative experiments are conducted to investigate the reaction mechanism, and it has proved that the presence of H+ is crucial to the fabrication of rough surface characteristic. The as-synthesized MoO2 microspheres have been applied as ion-to-electron transducers for potentiometric sensors. And the fabricated potentiometric sensor exhibits fast potentiometric response and good potential stability, which can be due to the good ion-to-electron transduction ability and high capacitance of the introduced MoO2 microspheres.

The development of a site-specific and covalent attachment methodology is crucial for antibody–biotin conjugates to preserve the antigen-binding ability of antibodies and yield homogeneous products. In this study, an engineered photoactivatable Z-domain variant [an UV-active amino acid benzoylphenylalanine (Bpa) was genetically incorporated into the Z-domain] carrying one biotin molecule (Z Bpa –Biotin) was prepared by employing aminoacyl-tRNA synthetase/suppressor tRNA and Avitag/BirA techniques. The site-specific and covalent attachment of IgG–biotin conjugates, viz. photo-biotinylated IgG, was successfully achieved after UV exposure by combining the inherent Fc-binding capability of the Z-domain with the formation of covalent bond by the photo-crosslinker. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis assay showed that more than 90% of IgGs conjugated with Z Bpa –Biotin molecules suffered 3 h UV irradiation. Further pepsin digestion analysis confirmed that the Z Bpa –Biotin was conjugated to the Fc fragment of IgG without interference. We took the tumor biomarker carcinoembryoic antigen (CEA) as model to evaluate the detection efficiency of the site-specific photo-biotinylated IgG in biosensing application using surface plasmon resonance (SPR) technology. The photo-biotinylated IgG coated surface gave a limit of detection (LOD) of 2 ng mL -1 , is 5-fold lower than that of the randomly NHS-biotinylated IgG (10 ng mL -1 ). Given that the (strept)avidin–biotin complex is extensively used in immunoassays, the proposed method for biotinylated IgG provides a powerful approach to further expand related applications.

Targeting recombinant proteins at highly extracellular production in the culture medium of Escherichia coli presents a significant advantage over cytoplasmic or periplasmic expression. In this work, a recombinant protein between ZZ protein and alkaline phosphatase (rZZ–AP) was constructed. Because rZZ-AP has the IgG-binding capacity and enzymatic activity, it can serve as an immunoreagent in immunoassays. However, only a very small portion of rZZ–AP is generally secreted into the aqueous medium under conventional cultivation procedure. Hence, we emphasized on the optimization of the culture procedures and attempted to dramatically enhance the yield of extracellular rZZ–AP from E. coli HB101 host cells by adding sucrose, glycine, and Triton X-100 in the culture medium. Results showed that the extracellular production of rZZ–AP in the culture medium containing 5% sucrose, 1% glycine, and 1% Triton X-100 was 18.6 mg/l, which was 18.6-fold higher than that without the three chemicals. And the β-galactosidase activity test showed that the increased extracellular rZZ–AP was not due to cell lysis. Further analysis suggested a significant interaction effect among the three chemicals for the enhancement of extracellular production. Ultrastructural analysis indicated that the enhancement may be due to the influence of sucrose, glycine, and Triton X-100 on the periplasmic osmolality, permeability, or integrity of the cell wall, respectively. This proposed approach presents a simple strategy to enhance the extracellular secretion of recombinant proteins in the E. coli system at the process of cell cultivation.

In contrast to machine recognizers that rely on training with large handwriting data, humans can recognize handwriting accurately on learning from few samples, and can even generalize to handwritten characters from printed samples. Simulating this ability in machine recognition is important to alleviate the burden of labeling large handwriting data, especially for large category set as in Chinese text. In this paper, inspired by human learning, we propose a cross-modal prototype learning (CMPL) method for zero-shot online handwritten character recognition: for unseen categories, handwritten characters can be recognized without learning from handwritten samples, but instead from printed characters. Particularly, the printed characters (one for each class) are embedded into a convolutional neural network (CNN) feature space to obtain prototypes representing each class, while the online handwriting trajectories are embedded with a recurrent neural network (RNN). Via cross-modal joint learning, handwritten characters can be recognized according to the printed prototypes. For unseen categories, handwritten characters can be recognized by only feeding a printed sample per category. Experiments on a benchmark Chinese handwriting database have shown the effectiveness and potential of the proposed method for zero-shot handwriting recognition.

Protein A affinity chromatography is an important technique that is widely used in purifying polyclonal and monoclonal antibodies. However, improving the IgG loading capacity of protein A affinity materials remains crucial. In this study, a smaller divalent IgG binding molecule derived from the B domain of protein A, i.e., ZZ-domain, was used to develop an affinity adsorbent with high IgG loading capacity by improving the unit area yield of the site-specific immobilization affinity ligand. The engineered ZZ-Cys was tightly immobilized onto Sepharose support via the covalent incorporation of a cysteine handle and a maleimide group, with oriented manner and divalent IgG binding capacity, thereby resulting in homogenous conjugates, namely, Sepharose–ZZSA. Approximately 1.19 mg of ZZ-Cys was coupled onto wet Sepharose g−1 and the maximum saturation binding capacity of Sepharose–ZZSA g−1 was approximately 23.80 mg of IgG. The smaller engineered ZZ-Cys can be produced at a lower cost than protein A and covalently conjugated onto matrix surface with high density and full IgG binding capacity. Thus, the proposed platform may be of general use for IgG purification in an efficient and economical manner.

Objective To observe the practicability and effect of tissue engineered skin for repairing the wound after escharectomy of third degree scald (TDSE) in rat model. Methods Epithelial cells and fibroblasts from newborn SD rats were isolated by enzyme digestion method and cultured in vitro, and porcine acellular dermal matrix (PADM) without cytotoxicity was prepared by hyperosmotic saline/sodium hydroxide method. The fibroblasts were mixed with bovine type Ⅰ collagen and inoculated on the surface of PADM. Third passage of cultured epidermal cells from newborn SD rats were inoculated on the collagen surface of the dermal matrix to obtain tissue engineered skin, and it was used to prepare epidermal cell sheet. Forty-eight SD rats with TDSE wound were randomly divided into two groups, then tissue engineered skin (experiment group), and epidermal cell sheet (control group) graftings were performed to cover the wounds respectively. Finally, gross observation and histological changes were observed in grafted area. The wound healing rate and wound contraction rate were compared between the two groups. Microvessel count (MVC) was performed with antiCD34 monoclonal antibody immunohistochemical staining technique, and vascular endothelial cells were labeled. Basal membrane of the skin was identified by immunohistochemical anti-Laminin staining technique. Results There was no obvious sign of acute rejection of the graft in both groups. The graft survival rate was 75.05%±3.69%, 83.12%±3.13% and 92.03%±3.87% at the 2th, 4th and 6th week respectively in the experimental group. The graft survival rate was 77.63%±3.23%, 83.17%±3.92% and 91.09%±3.35% at the 2th, 4th and 6th week in the control group. There was no significant difference between the two groups (P>0.05), but the contraction rate of the grafts was 9.13%±2.27%, 18.52%±3.40%, 23.92%±3.01% at the 2th, 4th, 6th week, respectively, in the experimental group, and 14.21%±3.05%, 29.12%±3.02% and 39.78%±3.42% at the 2th, 4th and 6th week in the control group. It was significantly lower than that of the control group (P

Despite the success of convolutional neural network (CNN) in conventional closed-set recognition (CSR), it still lacks robustness for dealing with unknowns (those out of known classes) in open environment. To improve the robustness of CNN in open-set recognition (OSR) and meanwhile maintain its high accuracy in CSR, we propose an alternative deep framework called convolutional prototype network (CPN), which keeps CNN for representation learning but replaces the closed-world assumed softmax with an open-world oriented and human-like prototype model. To equip CPN with discriminative ability for classifying known samples, we design several discriminative losses for training. Moreover, to increase the robustness of CPN for unknowns, we interpret CPN from the perspective of generative model and further propose a generative loss, which is essentially maximizing the log-likelihood of known samples and serves as a latent regularization for discriminative learning. The combination of discriminative and generative losses makes CPN a hybrid model with advantages for both CSR and OSR. Under the designed losses, the CPN is trained end-to-end for learning the convolutional network and prototypes jointly. For application of CPN in OSR, we propose two rejection rules for detecting different types of unknowns. Experiments on several datasets demonstrate the efficiency and effectiveness of CPN for both CSR and OSR tasks.

The pointing accuracy and stabilization property of the payload of a satellite depends on performance of attitude determination and control system (ADCS). An essential role of the ADCS is to stabilize the spacecraft in early operation stage and in the presence of anomalies. During this stage, the satellite may be subject to tumbling and a high-reliability method is deemed important to recover the satellite from this stage into its normal operation stage. In the paper, the use of magnetometer data and radio signal characteristics is investigated with the goal of determining the satellite tumbling rate confidently. The proposed method is applied to the PHOENIX CubeSat, which is a CubeSat that is developed by National Cheng Kung University, Taiwan as a part of the QB50 project, at its early orbit stage.

Convolutional neural network (CNN) has achieved great success in handwriting recognition. However, it relies on large set of labeled data in training and its performance will deteriorate when the data distribution varies. To solve this problem, traditional methods usually consider adaptation of the single top layer of CNN. To better reduce the distribution discrepancy, in this paper, we consider adaptation of all layers of CNN including both convolutional and full layers. Four variations of transformations are designed based on different assumptions about the space relations for adaptation of convolutional layers. In order to make adaptation of multiple layers, we propose to cascade the transformations of different layers to conduct adaptation in a deep manner, and therefore this method is denoted as deep transfer mapping (DTM). DTM can capture the information from different layers and minimize the data divergence under different information abstract levels, thus it is more powerful and flexible for domain adaptation. Experiments on the online Chinese handwriting dataset (OLHWDB) demonstrate the efficiency and effectiveness of the proposed method for unsupervised writer adaptation.

Convolutional neural networks (CNNs) have been widely used for image classification. Despite its high accuracies, CNN has been shown to be easily fooled by some adversarial examples, indicating that CNN is not robust enough for pattern classification. In this paper, we argue that the lack of robustness for CNN is caused by the softmax layer, which is a totally discriminative model and based on the assumption of closed world (i.e., with a fixed number of categories). To improve the robustness, we propose a novel learning framework called convolutional prototype learning (CPL). The advantage of using prototypes is that it can well handle the open world recognition problem and therefore improve the robustness. Under the framework of CPL, we design multiple classification criteria to train the network. Moreover, a prototype loss (PL) is proposed as a regularization to improve the intra-class compactness of the feature representation, which can be viewed as a generative model based on the Gaussian assumption of different classes. Experiments on several datasets demonstrate that CPL can achieve comparable or even better results than traditional CNN, and from the robustness perspective, CPL shows great advantages for both the rejection and incremental category learning tasks.

In handwriting recognition, the test data usually come from multiple writers which are not shown in the training data. Therefore, adapting the base classifier towards the new style of each writer can significantly improve the generalization performance. Traditional writer adaptation methods usually assume that there is only one writer (one style) in the test data, and we call this situation as style-clear adaptation. However, a more common situation is that multiple handwriting styles exist in the test data, which is widely appeared in multi-font documents and handwriting data produced by the cooperation of multiple writers. We call the adaptation in this situation as style-mixture adaptation. To deal with this problem, in this paper, we propose a novel method called K-style mixture adaptation (K-SMA) with the assumption that there are totally K styles in the test data. Specifically, we first partition the test data into K groups (style clustering) according to their style consistency, which is measured by a newly designed style feature that can eliminate class (category) information and keep handwriting style information. After that, in each group, a style transfer mapping (STM) is used for writer adaptation. Since the initial style clustering may be not reliable, we repeat this process iteratively to improve the adaptation performance. The K-SMA model is fully unsupervised which do not require either the class label or the style index. Moreover, the K-SMA model can be effectively combined with the benchmark convolutional neural network (CNN) models. Experiments on the online Chinese handwriting database CASIA-OLHWDB demonstrate that K-SMA is an efficient and effective solution for style-mixture adaptation.

Immobilized antibodies with oriented and homogeneous patterns are crucial to solid-phase molecular recognition assay. Antibody binding protein-based immobilization can effectively present the desired antibodies. However, steadily installing the stromatoid protein with site-specific attachment manner onto a matrix surface remains to be elucidated. In this study, we present an optimal protocol to tightly attach an immunoglobulin G (IgG)-binding protein (Z-domain) through covalent incorporation of Cys-tag and maleimide group onto polystyrene surface to guarantee site-specific, oriented, and irreversible attachment, resulting in a highly efficient platform for three-dimensional IgG immobilization. The actual IgG-binding characteristic of immobilized Z-Cys was investigated by employing affinity chromatography and size exclusion chromatography. And the efficacy and potential of this platform was demonstrated by applying it to the analysis of interaction between rabbit anti-HRP IgG and its binding partner HRP. The proposed approach may be an attractive strategy to construct high performance antibody arrays and biosensors given that the antibody is compatible with the Z-domain.

Constructing a recombinant protein between a reporter enzyme and a detector protein to produce a homogeneous immunological reagent is advantageous over random chemical conjugation. However, the approach hardly recombines multiple enzymes in a difunctional fusion protein, which results in insufficient amplification of the enzymatic signal, thereby limiting its application in further enhancement of analytical signal. In this study, two site-specific biotinylated recombinant proteins, namely, divalent biotinylated alkaline phosphatase (AP) and monovalent biotinylated ZZ domain, were produced by employing the Avitag–BirA system. Through the high streptavidin (SA)–biotin interaction, the divalent biotinylated APs were clustered in the SA–biotin complex and then incorporated with the biotinylated ZZ. This incorporation results in the formation of a functional macromolecule that involves numerous APs, thereby enhancing the enzymatic signal, and in the production of several ZZ molecules for the interaction with immunoglobulin G (IgG) antibody. The advantage of this signal amplification strategy is demonstrated through ELISA, in which the analytical signal was substantially enhanced, with a 32-fold increase in the detection sensitivity compared with the ZZ–AP fusion protein approach. The proposed immunoassay without chemical modification can be an alternative strategy to enhance the analytical signals in various applications involving immunosensors and diagnostic chips, given that the label-free IgG antibody is suitable for the ZZ protein.

Including MPBTCA, which is a literature known compound, seven BODIPY dyes have been characterization by varied physical methods, such as UV-visible absorption spectroscopy, low energy photo-electron spectroscopy (AC-2), HOMO-LUMO DFT/TDDFT calculation. All seven BODIPY dyes have absorption max around 535-545 nm, which is significantly longer than 499 nm of 4,4-difluoro-1,3,5,7,8-pentamethyl-4-bora-3a,4a-diaza-s-indacene (PM 546). Having structural variation on donor group, acceptor group, donor -spacer, acceptor -spacer, and the substituent on boron, some BODIPY dyes exhibit small extinction coefficient or spectral integral in solution (MPCtBTCA, MPBT-pyO, MPBTT-pyO, MTBTCA), broadening absorption spectral profile (MTBTCA), weak intramolecular charge transfer characteristics (MPBT-pyO, MPBTT-pyO, MTBTCA), too low LUMO energy level (PPBTCA), insufficient dye-uptake by TiO2 FTO (MPBT-pyO, MPBTT-pyO, MTBTCA). Accordingly, two of the seven BODIPY dyes, MPBTCA and MPBTTCA, do not show the adverse properties like other BODIPY dyes. With our improving TiO2 FTO dyeing method, namely solution dropping method, high performance dye-sensitized solar cells (DSCs) have been realized by MPBTCA and MPBTTCA photosensitizers. The power conversion efficiency of 6.3% and 6,4% have been achieved by MPBTCA and MPBTTCA DSCs, respectively. To the best of our knowledge, MPBTCA and MPBTTCA are the most efficient dyes for the donor and acceptor 2,6-disubstituted BODIPY DSCs so far.

A new one-dimensional (1D) coordination polymer, [Pb2(psa)(phen)2(NO3)2]n, has been synthesized by the method of hydrothermal reaction and characterized by elemental analysis, FT-IR and X-ray single-crystal diffraction (where H2psa is phenylsuccinic acid and phen is 1,10-phenanthroline). The single-crystal X-ray analysis showed that the complex has a dinuclear core stabilized by bridging phenylsuccinic acids and nitrate anions. The coordination number of the two Pb(II) atoms are 7 and 6, with the stereochemically active lone pair, resulting in the hemidirected geometry for the complex. The complex contain a 1D chain, which is further extended into two-dimensional supramolecular architecture through hydrogen bonds, C-H···π, and π···π interactions.

Writer adaptation is an important topic in handwriting recognition, which can further improve the performance of writer-independent recognizer. In this paper, we propose combining the neural network classifier with style transfer mapping (STM) for unsupervised writer adaptation, which only require writer-specific unlabeled data, and therefore is more common and efficient compared to supervised adaptation. We use some techniques like dropout, ReLU, momentum, and deeply supervised strategy to improve the performance of the neural network classifier. For a specific writer in the test data, an adaptation layer is added to the pre-trained neural network classifier. In adaptation process, only the parameters in adaptation layer are updated while other parameters of the neural network are kept unchanged. To train the adaptation layer, we use the same technology as STM learning but redefine the source point set, target point set and the corresponding confidence. Experiments on the online Chinese handwriting database CASIA-OLHWDB1.1 demonstrate that our method is very efficient and effective in improving classification accuracy. The experimental results also show that our proposed method outperforms the previous proposed learning vector quantization (LVQ) and modified quadratic discriminant function (MQDF) with STM methods for writer adaptation.

As a result of military conflict, terrorist attacks, industrial and traffic accidents, the incidence of burn-blast combined injury would be escalating. The burn-blast combined injury was a major clinical problem accompanied by multiple complications and high mortality. The lungs were the most severely injured organ in burn-blast combined injury. Dysfunction of ventilation and gas exchange produced by lung damage could affect oxygen supply to organs and systemic tissues, and is one of the pathophysiological changes resulting in shock and other complications. Previous research has indicated that most of alveolar walls were ruptured, capillaries ruptured, and pulmonary capillary endothelial cells were damaged in the lungs after burn-blast combined injury, and they were followed by pulmonary edema and hemorrhage followed by disorders in ventilation and gas exchange, ending in ischemia and hypoxia of systemic organs. So the treatment of lung injury is the major measure for the treatment of burn-blast combined injury. The pathogenesis and treatment of lung injury in burn-blast combined injury are briefly summarized in this article.

Highly efficient protein immobilization is extremely crucial for solid-phase immunoassays. We present a strategy for oriented immobilization of functionally intact immunoglobulin G (IgG) on a polystyrene microtiter plate via iminodiacetic acid (IDA)-Ni(2+) and ZZ-His protein interaction. We immobilized a ZZ-EAP (Escherichia coli alkaline phosphatase)-His fusion protein, which exhibits Fc binding, His tag, and intrinsic AP activities, and analyzed it against the interaction between rabbit IgG anti-horseradish peroxidase (anti-HRP) and its binding partner HRP to investigate the specificity and efficacy of this method. We compared the IDA-Ni(2+)-(ZZ-His) method with ZZ-EAP random immobilization using sandwich enzyme-linked immunosorbent assay, and the results showed that the former method had an enhanced signal, 10-fold higher sensitivity, and a wider linear range. Thus, the proposed method allows a broad range of oriented immobilized functionally intact IgG antibodies on polystyrene plates using only one type of IDA-Ni(2+) chelate surface because the ZZ protein can bind to the Fc region of various IgGs.

Due to the natural disasters, the transmission line fault has randomness. In order to describe the uncertainty of the transmission line fault, the conditional value-at-risk (CVaR) theory is introduced to quantify the uncertainty risk caused by transmission line failure. A stochastic optimal dispatch model of the power system considering the security risk constraint is proposed in this paper, using the sample average approximation (SAA) method and the analytic method to solve the model. The influence on the result of stochastic optimization dispatching is analysed by different conditional value at risk and confidence levels. The simulations demonstrate that the stochastic optimal dispatch model considering the security risk constraint is reasonable and provides a theoretical basis for the stochastic optimization dispatching of the power system considering line failure.

The penetration of a large number of plug-in hybrid electric vehicles (PHEVs) has introduced severe challenges to power grid operation. In this paper, the grid-connected PHEV model is first proposed to reflect the charge/discharge property of PHEV. Then, a simulation approach is developed to study the probability distributions of the aggregate load and available vehicle to grid (V2G). capacity of PHEVs. Simulation results show that the charging and discharging capacities have the characteristic of normal distribution．

A bidding system of peak regulation right based on multi-agent is proposed according to the property of the peak regulation right. Then, the biggest goals of social benefits of all power generation companies are developed based on bidding system. Simultaneously bidding strategy of peak regulation right of the biggest goals of social benefits of all power generation company agents and internal cost optimization strategy of electricity generation companies are respectively raised for the goals. Example analysis shows that the proposed Bidding system takes on better viability and effectiveness.

A facile approach for the production of a reusable immobilized recombinant Escherichia coli biotin ligase (BirA) onto amine-modified magnetic microspheres (MMS) via covalent cross-linking catalyzed using microbial transglutaminase (MTG) was proposed in this study. The site-specifically immobilized BirA exhibited approximately 95% of enzymatic activity of the free BirA, and without a significant loss in intrinsic activity after 10 rounds of recycling (P > 0.05). In addition, the immobilized BirA can be easily recovered from the solution via a simple magnetic separation. Thus, the immobilized BirA may be of general use for in vitro biotinylation in an efficient and economical manner.

In the present study, we constructed plasmid pUC-ZZ-EGFP to express Pro-ZZ-EGFP using ZZ peptide (a synthetic artificial IgG-Fc-fragment-binding protein derived from the B domain of staphylococcal protein A) and enhanced green fluorescent protein (EGFP). Without induction with isopropyl-β-D: -thiogalactopyranoside, the chimeric protein was effectively expressed in Escherichia coli HB101. Its affinity constant binding IgG was 2.6 × 10(8) M(-1) obtained by competitive enzyme-linked immunosorbent assay, indicating that the ZZ peptide retains the native structure in Pro-ZZ-EGFP. The application of immunofluorescence assay for detecting the Mycoplasma pneumoniae IgG antibody, Pro-ZZ-EGFP, exhibited a good signal comparable in brightness and fluorescence pattern with the signal generated using the fluorescein isothiocyanate-labeled anti-human IgG. The result indicates that Pro-ZZ-EGFP possesses great potential for clinical immunofluorescence IgG test as an alternative versatile fluorescent antibody.

Dear Editor: Cryptococcosis is an unusual opportunistic infection, and is characterized by a high mortality rate, especially among those with cryptococcaemia1. Cryptococcal skin lesions are often polymorphous in appearance. However, widespread cutaneous lesions and necrotizing fasciitis (NF) have rarely been reported. Here, we present a case of disseminated cryptococcosis with widespread cutaneous lesions, NF and cryptococcemia, occurring in an immunosuppressed patient. A 41-year-old woman was transferred to our hospital, with a history of skin necrosis on the right lower limb and high fever for 17 days, and erythemas, indurations, and abscesses on the other three limbs for 14 days. She was diagnosed as NF in another hospital, and treated with meropenem empirically, but without noticeable effect. She suffered from chronic glomerulonephritis, chronic renal insufficiency, and was receiving maintenance immunosuppressive therapy with prednisone (30 mg/d). On examination, black necrotic skin, bare subcutaneous tissue and multiple abscesses, mainly situated on the right leg, were the most obvious clinical manifestation (Fig. 1). Multiple erythemas, indurations and abscesses could be found on the other three limbs. Chest x-ray demonstrated bilateral infiltration in the lung, with pleural effusion on the right. Incision and drainage of the abscess were performed immediately, and thorough surgical debridement was performed 3 days later. On the 7th hospital day, pathological examination reported encapsulated yeast in subcutaneous tissue, suggesting Cryptococcus neoformans (Fig. 2). This was also isolated and identified (VITEK 2-compact) from blood, and the wound. A follow-up culture of cerebrospinal fluid was negative. When the definite diagnosis of disseminated cryptococcosis, cryptococcemia, cryptococcal NF, bilateral pulmonary infection and renal failure had been established, intravenous fluconazole (400 mg daily) was initiated. This dosage of fluconazole was continued for one month, and was then reduced by half, for another month. An oral maintenance dose was then given, for a further 4 months. She was discharged 54 days after admission, with her wounds completely closed with razor-thickness skin grafts. Fig. 1 Black necrotic skin, bare subcutaneous tissue and multiple abscesses on right leg. Fig. 2 (A) H&E staining of the subcutaneous tissue (%400). (B) Periodic acid-schiff staining of the yeast cells in subcutaneous tissue (%400). (C) Electron microscope image of encapsulated cells of Cryptococcus neoformans (%5,000). Cutaneous dissemination occurs in approximately 10% of cases with cryptococcosis2. Most patients with cutaneous involvement have lesions, consisting of ecchymosis, papules, nodules, vesicles, ulcers, abscesses, and very rarely, NF3,4. The patients with cryptococcal NF are usually treated empirically for a presumed bacterial infection, without response, as in the present case. C. neoformans can be isolated from blood cultures in 10% to 30% of patients with cryptococcosis1. Previous studies of patients with cryptococcemia have shown a high mortality rate, which was reported to be between 31% and 41%1,5. Cryptococcaemia signifies a fulminant form of cryptococcal disease, and requires early diagnosis, and prompt antifungal therapy. Antifungal therapy is the cornerstone to treat disseminated cryptococcosis and cryptococcemia. However, for NF, and serious, large areas of cutaneous infections, surgical treatment is indispensable. Thorough debridement and drainage, reducing the chance of hematogenous spread, and preventing muscle necrosis, sepsis and death, were one of the keys to cure the patient. This report highlights the need to recognize this rare infectious disease and its clinical manifestations, especially among those patients who are receiving treatments that produce a state of immunosuppression.

Based on Extreme Value Theory (EVT), the Generalized Pareto Distributions (GPDs) of meteorological variables wind speed and freezing precipitation is simulated. Considering the dependence of them, a joint probability distribution is calculated by the Copula function. Further more, the probability distributions of ice loads and wind loads on transmission lines are analyzed, and the failure probability of broken lines and collapsed towers under ice storms is calculated. The accuracy and validity of this analytical method is demonstrated with comparison between numerical results and the historical datas of Chen Zhou power transmission systems.

Large-scale wind power incorporated into power grid brings new challenges to optimal dispatch of power system. Especially, wind power at different locations may has a significant degree of correlation. A copula function was used to characterize the Joint Probability Distribution (JPD) of wind power from multiple wind farms considering their correlation. An optimal dispatch model based on Chance Constrained Programming (CCP) for power system with multiple wind farms was set up. And Sample Average Approximation (SAA) was proposed to transform the chance constrains. Finally Genetic Algorithm (GA) was employed to solve the optimal model. Simulation results indicate that copula function can well express the correlation of wind power from multiple wind farms and SAA has been a dramatic increase and improvement on the search of solution.

Based on different bidding decisions with heterogeneous expectations of market participants, a dynamic model of electricity market considering power network constraints is proposed. This model is represented by a discrete difference equations embedded with the optimization problem of market clearing. By using the nonlinear complementarity function, the complex dynamic behaviors of electricity market are simulated and analyzed. The Nash equilibrium and its stability, the periodic and even chaotic dynamic behaviors beyond the stability region of Nash equilibrium are investigated.

Several large scale failures of power system took place due to extreme weather disaster recent years, which aroused the consideration of power network security operation. Considering that the line failure events caused by natural disaster presented random characteristic, using Poisson distribution theory to depict the probability of line failure, a stochastic power system optimal dispatch model based on chance constraints theory was also proposed. We adopted the Differential Evolution algorithm to calculate the total loss based on Monte-Carlo simulation. The results of IEEE 9-bus case study imply that the dispatch model will give full consideration of weather effects, and provide a more reasonable dispatch plan for power system disaster prevention and reduction.

An important aspect of simulation modeling of the logistics center is the optimization and debugging. Usually it takes lengthy time to debug the logistics center simulation model by the traditional method. This paper presented a new method to debug simulation model. Through analyzing the data streams of the simulation model, the dominant sets of model parameters were identified to modify the model. The results show that this method can enhance the debug efficiency of model simulation.

Wind power at different locations may has a significant degree of correlation. A copula function, in this paper, is employed to characterize the Joint Probability Distribution (JPD) of wind power from multiple wind farms considering their correlation. Based on this, an optimal dispatch model of power system with multiple wind farms is proposed based on Chance Constrained Programming (CCP) to describe the randomness of wind power. And a new method named Sample Average Approximation (SAA) is used to transform the chance constrians in CCP. Finally the Particle Swarm Optimization (PSO) is used to solve the dispatch model. Simulation results show the affectivity of this model and method, which will be highly useful for optimal dispatch of power system with multiple wind farms.

Preventing high-voltage power transmission lines ice-covered is ensure to power system the important guarantee of safe and reliable operation in the extreme weather. The size of anti-ice critical current is reasonable or not will directly affect the anti-ice effect. This paper conducts a comprehensive analysis of thermal balance process of the wire surface, and proposes a critical current model to anti-ice. In this paper, the minimum melting ice current of under the ultra-thin ice cover (0.05mm) circumstance is regarded as the anti-ice currents. Finally, by the model established in this article, calculating critical current of some typical wires in Hunan electric power grid, and the result is compared with result of existing literature made the critical current model, verified accuracy of model.

In this paper,it proposes insulator flashover probability prediction model based on Markov chain and ARMA-GARCH. It provides a foundation for risk evaluation of rainstorm of power system. First,this model daily precipitation forecasting model which combined Markov chain with ARMA-GARCH based on self-dependency and time-varying of atmosphere factor; and then according to rainfall’s impact on insulator’s pollution raining flashover,the paper raises the probability prediction model of insulator flashover;Ultimately, we can predict the insulator flashover’s probability. Through Historical data of Hunan Grid to calculate the probability of flashover, and compares with the actual situation it shows that the method can achieve rapid, accurate prediction of power insulator flashover probability.

This study aimed to investigate changes in the expression of human leukocyte antigen-DR (HLA-DR) on CD14+ monocytes in the peripheral blood of burn victims with delayed resuscitation in relation to the development of sepsis, and the effect of carbachol in vitro. The study population comprised 25 people with burns of at least 30% of total body surface area and delayed resuscitation, and 20 healthy volunteers as controls. Peripheral blood was collected on post-burn days 1, 3, 7, 14 and 28. When 7 participants developed sepsis, their peripheral blood was drawn on 2 consecutive days. Expression of HLA-DR on CD14+ monocytes in peripheral blood of burned participants was lower than that of controls, and fell further with the development of sepsis, when the rate and concentration of tumour necrosis factor-alpha (TNF-alpha) rose above those of controls and burned participants without sepsis. Expression of HLA-DR on CD14+ monocytes was negatively correlated with interleukin-10 (IL-10) levels on post-burn days 1, 7 and 28. In vitro, HLA-DR expression on monocytes also decreased with lipopolysaccharide (LPS) stimulation, but after treatment with carbachol, rose in a concentration-dependent manner. Thus expression of HLA-DR on CD14+ monocytes may be a useful parameter for monitoring the immune function of burn victims with and without sepsis. Carbachol significantly inhibited LPS-induced immunosuppression in human monocytes in vitro.

Two-factor and three-level fractional factorial design was employed for evaluation of the effect of Glycine and Triton X-100 on the secretion and expression of ZZ-EGFP fusion proteins. Varying contents of glycine (0%, 1%, 2%) and Triton X-100 (0%, 1%, 2%) were added into shaking flasks, respectively, and supplied with appropriate volume of ampicillin (total 9 combinations; group at concentration zero serving as control) to promote more ZZ-EGFP diffuse into liquid culture medium. Fluorescent intensity in the culture supernatant was detected. A standard curve could be generated on the basis of fluorescent intensity and protein concentration. The expression level of ZZ-EGFP fusion proteins was estimated by checking the protein standard curve concentration fluorescene intensity. Results show that when the culture medium contains 2% Glycine and 1% Triton X-100, the expression level of ZZ-EGFP was able to be greatly increased. Further experiments revealed that absorbance value (A600) in the experiment group, whose culture medium contains 2% Glycine and 2% Triton X-100, is significantly lower than other groups in the present experiment. These results indicate that the culture medium containing appropriate quantity of Glycine and Triton X-100 is favourable to the secretion and expression level of ZZ-EGFP in gene-engineering bacteria Escherichia coli HB101.