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For the current problem that grate bed can not recover its own waste heat in the course of cycle working, combined with the structure of the chain grate and hot air flow process, a three-section heat recovery unit of grate bed and waste heat recovery hot air flow process are designed. According to the principle of repeated convective heat transfer, the amount of recovering waste heat of heat recovery unit is estimated, and simulation analysis is conducted by using fluent software. The results show: after three heat exchange between the hot exhaust gas at around 100°C and the grate bed, the hot gas at a temperature of around 427 °C can be obtained, and the waste heat recovery rate is above 60%; simulation results are compared with the estimated value so that it can be obtained that the differences between the two values in the temperature of three-section outlet gas are basically consistent, about 8°C, 4°C, 7°C respectively, which verifies the effectiveness of the heat recovery unit design and the accuracy of Fluent simulation.

Considering the current problems of low temperature of recovered gas, the direct gas emission of the fourth cooling zone in the operation of the annular cooler, thermal airflow process for the annular cooler is improved by analyzing the thermal airflow process and the structure of the annular cooler and using the principle of repeated convective heat transfer. Thus the above-mentioned problem can be solved. Simulation model of its thermal airflow process is established and the simulation results, obtained by using Fluent software, are as follows: the temperature of the gas in the first cooling zone entering the rotary kiln of the improved is about 110°C higher than that of the unimproved, the temperature of the gas in the second cooling zone entering the preheat zone I of the chain grate of the improved is about 150°C higher than that of the unimproved, and the temperature of the gas in the fourth cooling zone entering the downdraft drying zone of the chain grate of the improved is about 50°C higher than that of the unimproved. Pellet heat recovery efficiency is increased significantly.

The major challenge of prion disease diagnosis at the presymptomatic stage is how to sensitively or selectively discriminate and detect the minute quantity of disease-associated prion protein isoform (PrP(Res)) in complex biological systems such as serum and brain homogenate. In this contribution, we developed a dual-aptamer strategy by taking the advantages of aptamers, the excellent separation ability of magnetic microparticles (MMPs), and the high fluorescence emission features of quantum dots (QDs). Two aptamers (Apt1 and Apt2), which can recognize their two corresponding distinct epitopes of prion proteins (PrP), were coupled to the surfaces of MMPs and QDs, respectively, to make MMPs-Apt1 and QDs-Apt2 ready at first, which then could be coassociated together through the specific recognitions of the two aptamers with their two corresponding distinct epitopes of PrP, forming a sandwich structure of MMPs-Apt1-PrP-Apt2-QDs and displaying the strong fluorescence of QDs. Owing to the different binding affinities of the two aptamers with PrP(Res) and cellular prion protein (PrP(C)), both of which have distinct denaturing detergent resistance, our dual-aptamer strategy could be applied to discriminate PrP(Res) and PrP(C) successfully in serum. Further identifications showed that the present dual-aptamer assay could be successfully applied to the detection of PrP in 0.01% brain homogenate, about 1000-fold lower than that of commonly applied antibody-mediated assays, which can detect PrP just in 10% brain homogenate, indicating that the present designed dual-aptamer assay is highly sensitive and adequate for clinical diagnosis without isolation of target protein prior to assay.

Objective The purpose of this study was to develop a new method to regenerate articular cartilage of the temporomandibular joint (TMJ) by transplantation of free autogenous costal perichondrium (PC). Study design In the study, 50 adult rabbits received the operation. For the surgery in the test group, the rabbits were randomly matched in pairs within the group and underwent the surgery of cross transplantation of costal PC after trimming the articular surface of the condyle. Operations were carried out in the same way in the experimental group except for PC transplantation. Instead, the suture was stitched in stratified order in the control group. Examination methods included observation of sections under the microscope, observation of specimens under the electron microscope, proliferating cell nuclear antigen (PCNA) staining, and biochemical analysis of glucuronic acid (GA) content and collagen content. The results of different groups were compared with ANOVA. Results The transplanted homologous PC escaped observable immune repulsion so that it could survive to form new joint cartilage with approximately normal tissue structure and biochemical constitution. The reproduction process was similar to the normal one, but was prolonged a little. At the later stage, the degeneration and calcification in the basal layer increased. However, because of its limited scope, no apparent effect on cartilage growth and function was observed. Conclusions Homologous xenografting of free costal PC will not result in an apparent immunorejection of the host. Instead, the grafts can maintain their existence by obtaining nutrition from surrounding tissues and regenerate cartilage tissue.

Aptamer-adapted silver nanoparticles (Apt-AgNPs) were developed as a novel optical probe for simultaneous intracellular protein imaging and single nanoparticle spectral analysis, wherein AgNPs act as an illuminophore and the aptamer as a biomolecule specific recognition unit, respectively. It was found that streptavidin-conjugated and aptamer-functionalized AgNPs show satisfactory biocompatibility and stability in cell culture medium, and thus not only can act as a high contrast imaging agent for both dark-field light scattering microscope and TEM imaging but also can inspire supersensitive single nanoparticle spectra for potential intercellular microenvironment analysis. Further investigations showed that caveolae-related endocytosis is likely a necessary pathway for Apt-AgNPs labeled PrP(c) internalization in human bone marrow neuroblastoma cells (SK-N-SH cells). The integrated capability of Apt-AgNPs to be used as light scattering and TEM imaging agents, along with their potential use for single nanoparticle spectral analysis, makes them a great promise for future biomedical imaging and disease diagnosis.

Purpose The present study evaluated the effects of platelet-rich plasma (PRP) and the latissimus dorsi muscle flap on osteogenesis and vascularization of tissue-engineered bone. Materials and Methods Bone marrow stromal cells (BMSCs) were subcultured, and PRP was obtained from the same dogs. Demineralized bone matrix (DBM) was prepared from homologous bone. The complexes of DBM/BMSCs/PRP were implanted into areas A and B on the left side of the dogs' backs; complexes of DBM/BMSCs without PRP were implanted in areas C and D on the right side of the same dog. The implants in areas A and C were wrapped with a latissimus dorsi muscle flap, and the implants in areas B and D were wrapped with inferior fascia. At 4, 8, and 12 weeks later, the implants were removed for evaluation. Results The radiographic evaluation, descriptive histologic analysis, and histologic quantitative analysis showed that the PRP/BMSCs/DBM complex was better than the BMSCs/DBM complex in both vascularization and osteogenesis of the ectopic tissue-engineered bones, and the complex wrapped with the latissimus dorsi muscle flap was better than that packed with superficial fascia without blood vessels. Conclusions The PRP and blood vessels in the latissimus dorsi muscle could cooperatively promote osteogenesis and vascularization in tissue-engineered bone.

Light scattered from nanoparticles (NPs) can easily be observed by the naked eye. Light-scattering signals from nanomaterials have been applied extensively for analysis (e.g., in biochemical and pharmaceutical sciences). Metal NPs with defined components, size and shape can be used as fluorescent analogs for labeling biomolecules in biochemical analysis and biological imaging, due to the colors of the scattered light, if excited with a white-light source. Enhanced light-scattering signals from aggregates of NPs induced by analytes can be used for monitoring molecular interaction or quantitative detection of analytes. Due to the advantages of simplicity and sensitivity, light-scattering spectrometric methods based on nanomaterials have shown great promise. In this contribution, we review applications of light-scattering signals from NPs in biochemical assay, pharmaceutical analysis and biological imaging.

To prepare chitosan nanospheres for loading of BMP-2 and to evaluate its size, zeta potential, appearance, degradation and release characteristic in vitro, and then to investigate its feasibility as a carrier for sustained release of BMP-2.The BMP-2 loaded chitosan nanospheres were prepared using ionic crosslinking method with tripolyphosphate (TPP) and chitosan. Transmission electron microscope was used to evaluate the morphological properties, and laser particle size analyzer was used to analyze particle size, Zeta potential and distribution. Lysozyme degradation experiment was performed to assess the biodegradation behavior. ELISA assay was used to determine the loading efficiency, encapsulation efficiency and in vitro drug release kinetics. The data was analyzed by SPSS 19.0 software package.The BMP-2 loaded chitosan nanospheres were spherical in shape, smooth on surface and uniform dispersion without aggregation. The mean diameter was 150.85 nm. The dispersion index was 0.37, and zeta potential was +35.42 mV. The average loading efficiency and encapsulation efficiency were (56.83 ± 2.26)% and (68.24 ± 3.83)%, respectively. Release experiment in vitro showed that the releasing property of BMP-2 loaded chitosan nanospheres was consistent with two-phase kinetic regulation and BMP-2 was controlled to release from the chitosan nanospheres over 30 days.The BMP-2 loaded chitosan nanospheres prepared by ionic crosslinking method are successfully prepared which show a good controlled release property. It provides the basis for further application in bone tissue engineering.

It is generally believed that the failure of TBCs is attributed to the spallation occurred in the ceramic coat. The spallation is closed linked with sinuate morphology factors, including its amplitude and period, at the TGO/bond coat interface. In this work, dependence of the residual stress distribution on the sinuate morphology in the TBCs has been studied by means of Finite Element Method (FEM) simulation for isothermally annealed specimens. The simulation results indicated that the maximum value of residual stress existed inside the TGO layer. It was also found that the maximum residual stress occurred at different points, near the TGO/bond coat interface at the peak of the sinuate interface, while near the TGO/ceramic coat interface at the valley, respectively. And the maximum residual stress increased with increasing the ratio of the amplitude to period in the sine morphology, which has been proved by the thermal cycle experimental results.

Cuprous oxide nanoparticles (Cu2O NPs) possess unique physical and chemical properties which are employed in a broad variety of applications. However, little is known about the adverse effects of Cu2O NPs on organisms. In the current study, in vitro cytotoxicity of Cu2O NPs (ca. 60 nm in diameter) to the blood cells of freshwater fish Carassius auratus was evaluated. A concentration-dependent hemolytic activity of Cu2O NPs to red blood cells (RBCs) and the phagocytosis of Cu2O NPs by leukocytes were revealed. The results showed that dosages of Cu2O NPs greater than 40 μg/mL were toxic to blood cells, and could cause serious membrane damage to RBCs. The EC50 value of Cu2O NPs as obtained from RBCs and whole blood exposure was 26 and 63 μg/mL, respectively. The generation of reactive oxygen species and the direct interaction between Cu2O NPs and the cell membrane were suggested as the possible mechanism for cytotoxicity, and the intrinsic hemolytic active of Cu2O NPs was the main contributor to the toxicity rather than solubilized copper ions. The adsorption of plasma proteins on the surfaces of Cu2O NPs led to their aggregation in whole blood, and aggregate formation can significantly alleviate the hemolytic effect and subsequently mediate the phagocytosis of Cu2O NPs by leukocytes.

Molecular logic gates, which have attracted increasing research interest and are crucial for the development of molecular-scale computers, simplify the results of measurements and detections, leaving the diagnosis of disease either "yes" or "no". Prion diseases are a group of fatal neurodegenerative disorders that happen in human and animals. The main problem with a diagnosis of prion diseases is how to sensitively and selectively discriminate and detection of the minute amount of PrP(Res) in biological samples. Our previous work had demonstrated that dual-aptamer strategy could achieve highly sensitive and selective discrimination and detection of prion protein (cellular prion protein, PrP(C), and the diseases associated isoform, PrP(Res)) in serum and brain. Inspired by the advantages of molecular logic gate, we further conceived a new concept for dual-aptamer logic gate that responds to two chemical input signals (PrP(C) or PrP(Res) and Gdn-HCl) and generates a change in fluorescence intensity as the output signal. It was found that PrP(Res) performs the "OR" logic operation while PrP(C) performs "XOR" logic operation when they get through the gate consisted of aptamer modified reusable magnetic microparticles (MMPs-Apt1) and quantum dots (QDs-Apt2). The dual-aptamer logic gate simplifies the discrimination results of PrP(Res), leaving the detection of PrP(Res) either "yes" or "no". The development of OR logic gate based on dual-aptamer strategy and two chemical input signals (PrP(Res) and Gdn-HCl) is an important step toward the design of prion diseases diagnosis and therapy systems.

Although nanoparticles have been widely used as optical contrasts for cell imaging, the complicated prefunctionalized steps and low labeling efficiency of nanoprobes greatly inhibit their applications in cellular protein imaging. In this study, we developed a novel and general strategy that employs an aptamer not only as a recognizer for protein recognition but also as a linker for nanoreporter targeting to specifically label membrane proteins of interest and track their endocytic pathway. With this strategy, three kinds of nanoparticles, including gold nanoparticles, silver nanoparticles, and quantum dots (QDs), have been successfully targeted to the membrane proteins of interest, such as nucleolin or prion protein (PrP(C)). The following investigations on the subcellular distribution with fluorescent immunocolocalization assay indicated that PrP(C)-aptamer-QD complexes most likely internalized into cytoplasm through a classical clathrin-dependent/receptor-mediated pathway. Further single-particle tracking and trajectory analysis demonstrated that PrP(C)-aptamer-QD complexes exhibited a complex dynamic process, which involved three types of movements, including membrane diffusion, vesicle transportation, and confined diffusion, and all types of these movements were associated with distinct phases of PrP(C) endocytosis. Compared with traditional multilayer methods, our proposed aptamer-mediated strategy is simple in procedure, avoiding any complicated probe premodification and purification. In particular, the new double-color labeling strategy is unique and significant due to its superior advantages of targeting two signal reporters simultaneously in a single protein using only one aptamer. What is more important, we have constructed a general and versatile aptamer-mediated protein labeling nanoplatform that has shown great promise for future biomedical labeling and intracellular protein dynamic analysis.

The purpose of this study was to assess the clinical features and available treatment of multiple symmetric lipomatosis (MSL).A cohort of 15 cases with MSL registered in the Affiliated Hospital of Qingdao University was reviewed. The etiology, clinical manifestations, treatments and prognosis were also investigated.All the cases were performed sectionalized excisions to cut off the lipoma localized in the neck under general anesthesia. During the follow up period, 13 out of 15 cases were cured after the excision with acceptable appearance and normal local function. Two cases with surgical complications, the one was hematoma, and the other was lymphatic leakage. There were 2 cases with relapses under our follow-up visit.Sectionalized lipoma excision under general anesthesia is a relative safe method for MSL.

An ultra-sensitive detection strategy for prion protein is proposed based on the long range resonance energy transfer (LrRET) from quantum dots (QDs) to the surface of gold nanoparticles (AuNPs), in which process energy donor–acceptor separation distance ranges from 9 to 22 nm.

To investigate the growth situation of bone marrow stroma stem cells(BMSCs) cell-sheet and endothelial progenitor cells (EPCs) on demineralized bone matrix (DBM) and explore the effect of DBM/BMSCs cell-sheet and DBM/EPCs complex on the construction of functional and vascularized tissue-engineered bone in mongrel.BMSC cell-sheet was prepared with cell-sheet engineering approach, EPCs were isolated from canine bone marrow and DBM was prepared from homologous bone. BMSCs cell-sheet and EPCs were inoculated on DBM respectively and observed by inverted phase contrast microscope and scanning electron microscope. The porosity of DBM was measured.The DBM/BMSCs cell-sheet and DBM/EPCs complex were successfully constructed. The BMSCs cell-sheet and EPCs adhered to DBM well and grew rapidly.The BMSCs cell-sheet and EPCs have good biocompatibility with DBM. The complex of DBM/ BMSCs cell-sheet, DBM/EPCs could provide good conditions to acquire functional and vascularized tissue-engineered bone. Supported by National Natural Science Foundation of China (Grant No.30872896) and Natural Science Foundation of Shandong Province (Grant No.Y2008C77).

Although holding the advantages of both an aptamer and a molecular beacon (MB), a molecular aptamer beacon (MAB) needs complicated and expensive modifications at both of its ends and usually has a high background signal because of the low energy transfer efficiency between the donor and the acceptor. To overcome these shortcomings, in this study, we develop a long-range resonance energy transfer (LrRET) system by separating the donor from the acceptor, wherein only one end of the MAB is fluorescently labeled and acts as the energy donor and multiwalled carbon nanotubes (MWCNTs) are introduced as the energy acceptor. To test the feasibility of the newly designed MAB system, adenosine triphosphate (ATP) has been employed as a proof-of-concept target. It is found that the fluorescence of the designed MAB is completely quenched by MWCNTs, supplying a very low background signal. Then the quenched fluorescence is recovered significantly with the addition of ATP, so that ATP can be detected in the range of 0.8-80 μM with a limit of detection of 0.5 μM (3σ). Compared with the conventional fluorescence resonance energy transfer, the efficiency of LrRET between the dye and MWCNTs is much higher. Since only one end of the MAB needs the modification, the present strategy is simple and cost-effective. Furthermore, the use of MWCNTs can greatly reduce the fluorescence background of the MAB and supply a high sensitivity, showing its generality for detection of a variety of targets.

Nowadays, hydrogen peroxide (H(2)O(2)) has attracted more and more attentions in biochemical fields owing to its important role in biological systems. In this contribution, we propose a novel assay for the detection of H(2)O(2) based on the cleavage of ssDNA on gold nanoparticles (AuNPs). It was known that AuNPs could be stable in the presence of single-stranded DNA (ssDNA) which prevents the salt-induced aggregation of AuNPs in solution owing to the electrostatic repulsion. However, hydroxyl radical (HO*) generated from Fenton reaction could cleave the ssDNA and induce the aggregation of AuNPs. Therefore, color change from red to blue owing to the plasmon resonance absorption (PRA) of AuNPs can be observed by the naked eyes and enhancement of plasmon resonance light scattering could be measured with a common spectrofluorometer. The values of A(650)/A(520) of the PRA band were found to be linearly proportional to the concentration of H(2)O(2) in the range of 2.0 x 10(-7) to 8.0 x 10(-6) mol L(-1) with the limit of determination (LOD) being 40 nmol L(-1) (S/N=3), and thus the content of H(2)O(2) in rat encephalon extraction could be successfully detected with the recovery in the range of 98-103%.

A facile solution-phase synthesis route of highly uniform Cu(2)O nanospheres (Cu(2)O NPs) with the size of 57.7+/-4.7nm was developed, and then the nanoparticles were applied to live cell imaging under a common dark-field microscope. Starting from copper(II) salts, the synthesis of Cu(2)O NPs was made in the presence of cetyltrimethylammonium bromide (CTAB) by reducing the copper(II) with sodium borohydride (NaBH(4)) in aqueous medium and by aging process in the air. Monitoring of morphology evolution process of Cu(2)O NPs with scanning electron microscopy (SEM) and measuring of the UV-visible spectra showed that the synthesis of Cu(2)O NPs follows the reduction-oxidation coupled process of Cu(2+) into Cu(0) species at first and then the resulted Cu(0) species into Cu(2)O NPs in the air. Light scattering (LS) features have been measured with a common spectrofluorometer and a common dark-field microscope, and it was found that the as-prepared Cu(2)O NPs display strong blue scattering light and can be applied for cell imaging. If incubated with human bone marrow neuroblastoma, transferrin-conjugated Cu(2)O NPs can get into the cells and show strong pure blue light in cytoplasm. Further investigations showed that the Cu(2)O NPs could be applied for probes for conformation of proteins.

To study the effects of platelet rich plasma (PRP) on vascularization of tissue-engineered bone.Bone marrow stromal cell (BMSC) were isolated from iliac bone of dogs. PRP was obtained from the same dog and demineralized bone matrix (DBM) was prepared from homologous bone. Twelve dogs were divided into three groups and the back of each dog was divided into four areas. The DBM- BMSC- PRP was implanted in the area A and B; the DBM-BMSC without PRP was implanted in the area C and D. The implants in the areas A and C were wrapped using myo-fascia with blood vessel of latissimus dorsi. The implants in the area B and D were wrapped using superficial fascia of the back without blood vessel. The implants were taken out 4, 8 and 12 weeks later for examination.The degree of calcification and blood vessel formation of the implants was ABCD.Both PRP and vessels of latissimus dorsi muscle could promote calcification and vascularization in tissue-engineered bone, when used separately or in combination.

To study the effect of platelet-rich plasma (PRP) and latissimus dorsi myofascia with blood vessel on vascularization of tissue engineered bone in dogs.Bone marrow stromal cells (BMSCs) were isolated from iliac bone of dogs. PRP was obtained from the same dog. And demineralized bone matrix (DBM) were prepared from homologuous bone. ABCD 4 areas were divided on the back of dog. PRP/BMSCs/DBM was implanted around the vessels of lattisimus dorsi muscle in the A. PRP/BMSCs/DBM wrapped by superficial fascia in the B. BMSCs/DBM was implanted around vessels of lattisimus dorsi muscle in the C. BMSCs/DBM wrapped by superficial fascia in the D area of the same dog. 4, 8, 12 weeks after implantation, gross specimen and histology examination were made.Osteogenesis and blood vessel formation results were ABCD area.The results suggested that the PRP and latissimus dorsi myofascia with blood vessels could promote calcification and vascularization in tissue-engineered bone.

A novel type of leaf-like poly (p-phenylenediamine) (PpPD) microcrystal was prepared under mild conditions, which was successfully applied to the visual detection of Co(2+)in vitro and in tissue based on the extinction and light scattering features owing to the special etching effect of Co(2+) on the surface of the leaf-like microcrystal.

A simple, one-pot and controllable strategy is reported in this contribution for biomimetic synthesis and self-assembly of gold nanoparticles (Au-NPs). It involves our synthesized polyaldehyde dextran (PAD), which has been proved to be a biomacromolecule with excellent biocompatibility and biodegradability, acting as both a reducing agent and a stabilizer. The morphology of the as-prepared Au-NP assemblies can be controlled by adjusting the reaction conditions, such as the concentration of aldehyde in PAD, the reaction time and the temperature. Investigations of the mechanism suggest that stabilizers may distribute on different crystal facets of NPs non-uniformly owing to the different binding forces, and dipole-dipole interaction of NPs could be the main driving force for the assembly of Au-NPs. In addition, intermolecular hydrogen bonding interaction of stabilizers could also act as a possible driving force. The excellent biocompatibility of the Au-NP assemblies makes them promising candidates for fabricating future optical nanodevices and application in biological systems.

In this contribution, we report a molecular recognition between adenosine and its aptamer, which leads to the formation of a four-stranded tetraplex structures (G-quartet) of the aptamer. It is found that the formed G-quartet could induce the side-by-side self-assembly of gold nanorods (AuNRs) owing to the electrostatic interaction between the positive charge of cetyltrimethylammonium bromide (CTAB) on the AuNR surface and the negative charge of the formed G-quartet. Furthermore, the side-by-side self-assembly of AuNRs is characterized by the enhancement of plasmon resonance light scattering (PRLS) signals and the blue-shift of the longitudinal plasmon resonance absorption (LPRA) band owing to the plasmon resonance coupling. Then, based on the enhanced PRLS signals, a simple, highly selective and sensitive detection method for adenosine was developed in the range of 4.0-80.0 nM with the limit of determination of 2.0 nM, which is up to now the best sensitive optical detection method to our knowledge. This method has been successfully applied to the detection of adenosine phosphates in the brains of SD rats, which was in good agreement with a high-performance liquid chromatographic (HPLC) method.