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This article reports the preparation of three-dimensional (3D) mesoporous zinc oxide (ZnO) films and their application in solar cells. The films were obtained through electrochemical deposition in DMSO solutions by using PS colloidal crystal as templates. The ZnO films with inverse opal (IO) structure were obtained after removing the templates by thermolysis. The ordered porous ZnO films were used to prepare hybrid solar cells by infiltrating the films with poly(3-hexylthiophene) (P3HT) or P3HT:ZnO nanocomposite. Results showed that the interpenetrating network of both ZnO(IO) and P3HT can form continuous pathways for electron and hole transport. By infiltrating a P3HT:ZnO nanocomposite into the porous ZnO films, the photocurrent of the solar cell can be dramatically improved. The cell shows the V oc and I sc of 462 mV and 444.3 μA/cm 2 , respectively. By using a 420 nm cutoff filter, the cell retains about 80% and 50% of its original V oc and I sc after continuous white-light illumination (100 mW/cm 2 ) for 10 h. Stability of the device under above conditions was estimated to be 51 h.

In this work, a new type of dye-sensitized bulk-heterojunction hybrid solar cells has been developed. The heterojunction films were prepared to contain poly(3-hexylthiophene) (P3HT), N,N′-diphenyl glyoxaline-3,4,9,10-perylene tetracarboxylic acid diacidamide (PDI) and TiO2. In the architecture, TiO2 and P3HT were designed to act as the electron acceptor and donor. PDI was used as sensitizer to enhance the photon absorption. Results showed that by incorporation of PDI in the P3HT/TiO2 composite, the light absorption, exciton separation and photocurrent under white light were dramatically enhanced. Solar decay analyses showed that devices contained TiO2 required 12 h to obtain maximum current density and the addition of PDI did not affect the solar decay behavior and stability of device composed of P3HT/TiO2. The devices of P3HT, P3HT/TiO2, P3HT/TiO2/PDI could work for 5, 42, 45 h under continuous white light illumination (100 mW/m2) under the ambient condition.

Resistive random access memory (RRAM) has been recognized as one of the most promising candidates for next generation non-volatile memory due to its simple structure and excellent scalability. However, poor reliability is a serious issue for RRAM memory applications. To improve the reliability and endurance, many researchers changed the cell material, process and structure. Here, in this paper, we propose an error-correction code (ECC) method to improve RRAM chip reliability. BCH code is adopted in our configurable and adaptive-rate error correction scheme that the ECC correction capability changes when the error mode changes.

In order to enable multiple disciplines of medical researchers, clinical physicians and biomedical engineers working together in a secured, efficient, and transparent cooperative environment, we had designed an e-Science platform for biomedical imaging research and application cross multiple academic institutions and hospitals in Shanghai and presented this work in SPIE Medical Imaging conference held in San Diego in 2012. In past the two-years, we implemented a biomedical image chain including communication, storage, cooperation and computing based on this e-Science platform. In this presentation, we presented the operating status of this system in supporting biomedical imaging research, analyzed and discussed results of this system in supporting multi-disciplines collaboration cross-multiple institutions.

We describe an image division multiplexing digital holography approach, with which the noises are completely suppressed without loss of image bandwidth, even if the image and the noises are close to each other.

Intersecting line usually appears on the 3-way or 4- way interface spare parts, forming the curves of surfaces. During the course of processing by CNC machine, the CNC processing program established by using computer assistant programming will greatly improve the effectiveness of programming. However, the program worked out in this way need a huge amount of data. It is difficult to dig out the root reason of problem and to fix the problem. With the help of Macro program, give full play to the function of CNC system and the craft and experience of programmer, it will be easy to write out simple, easy understanding, flexible and easy using program. Keywords-CNC processing; Intersecting Line; Macro- program; Node

In this work, a soft lithographic approach has been developed to duplicate photoinduced surface-relief-gratings (SRGs) of azo polymer films to generate the surface pattern replicas composed of different materials on various substrates. For this purpose, thin films of an epoxy-based azo polymer (BP-AZ-CA) were prepared by spin-coating, and SRGs with different structures were inscribed by exposing the films to interference patterns of Ar(+) laser beams at modest intensity (150 mW/cm(2)). Using the azo polymer films as masters, stamps of poly(dimethylsiloxane) (PDMS) were prepared by replica molding. The PDMS stamps were then used to transfer the solutions of poly(3-hexylthiophene) (P3HT), multiwalled carbon nanotube (MWNT), and BP-AZ-CA to different substrates by contact printing. Through this process, surface pattern replicas made of the functional materials were obtained. The pattern formation and quality depended on the factors such as the solution concentration, contacting time in the printing process, and printing pressure. Under the proper conditions, the printed patterns showed the same grating periods as the masters and the same relief depths as the stamps (replicas of the masters). This approach, showing some attractive characteristics such as the easiness of master preparation and the versatility of soft fabrication processes, can be applied to the fabrications of optical functional surfaces, sensors, and photonic devices.

In this paper, an experimental approach to acquiring true spontaneous emission rate of optically-pumped InGaAs/GaAs quantum-well laser structure is described. This method is based on a single edge-emitting laser chip with simple sample processing. The photoluminescence spectra are measured at both facets of the edge-emitting device and transformed to the spontaneous emission rate following the theory described here. The unusual double peaks appearing in the spontaneous emission rate spectra are observed for the InGaAs/GaAs quantum-well structure. The result is analyzed in terms of Indium-rich island and Model-Solid theories. The proposed method is suitable for electrically-pumped quantum-well laser structures, as well.

In this paper, an absolute-phase unwrapping and speckle suppression approach to reconstruct a three-dimensional (3-D) image of an object with laser digital holography is described. This method offers three advantages to enhance the performance of the phase reconstruction technique. First, both speckle suppression and phase unwrapping are processed in the complex amplitude domain rather than in the single phase or amplitude domain. With this approach, the phase details of the object are better preserved upon phase reconstruction. Second, the proposed algorithm requires no threshold determination and thus achieves self-adaptive speckle suppression and robust phase unwrapping, in contrast to other methods. Finally, an improved dual-domain image denoising method is applied to further remove speckle-remnant-induced phase distortion. Ideal 3-D phase reconstruction results are obtained both theoretically and experimentally for the first time.

This study demonstrates that ligand-modified graphene quantum dots (GQDs) facilitate the simultaneous operation of multiple tasks without the need for external dyes. These tasks include selective cell labeling, targeted drug delivery, and real-time monitoring of cellular uptake. Folic acid (FA)-conjugated GQDs are synthesized and utilized to load the antitumor drug doxorubicin (DOX). The fabricated nanoassembly can unambiguously discriminate cancer cells from normal cells and efficiently deliver the drug to targeted cells. The inherent stable fluorescence of GQDs enables real-time monitoring of the cellular uptake of the DOX-GQD-FA nanoassembly and the consequent release of drugs. The nanoassembly is specifically internalized rapidly by HeLa cells via receptor-mediated endocytosis, whereas DOX release and accumulation are prolonged. In vitro toxicity data suggest that the DOX-GQD-FA nanoassembly can target HeLa cells differentially and efficiently while exhibiting significantly reduced cytotoxicity to non-target cells.

One key problem for continuity of patient care is identification of a proper method to share and exchange patient medical records among multiple hospitals and healthcare providers. This paper focuses in the imaging document component of medical record. The XDS-I (Cross- Enterprise Document Sharing – Image) Profile based on the IHE IT-Infrastructure extends and specializes XDS to support imaging “document” sharing in an affinity domain. We present three studies about image sharing solutions based on IHE XDS-I Profile. The first one is to adopt the IHE XDS-I profile as a technical guide to design image and report sharing mechanisms between hospitals for regional healthcare service in Shanghai. The second study is for collaborating image diagnosis in regional healthcare services. The latter study is to investigate the XDS-I based clearinghouse for patient controlled image sharing in the RSNA Image Sharing Network Project. We conclude that the IHE XDS/XDS-I profiles can be used as the foundation to design medical image document sharing for Various Healthcare Services.

G-protein-coupled receptors (GPCRs) comprise the largest family of integral membrane proteins and mediate most of the transmembrane signal transduction. Approximately 50 % of all marketed drugs target GPCRs, which makes this protein family the most important drug targets. Chemokine receptors belong to GPCRs, which were perceived as monomers decades ago. However, recently there are growing evidences indicating that most of GPCRs can form dimers or higher order oligomers. Some chemokine receptors are also found existing as homodimers or heterodimers. A large number of studies have suggested that homodimers or heterodimers may exhibit specific functions, which are different from their monomeric counterparts. Meanwhile, the appearance of dimers with new signaling properties gives new chance in the search for novel drug targets. In this review, we will mainly summarize the current knowledge of the dimerization of chemmokine receptors and its potential roles in drug discovery.

As there are urgent demands to bring medical imaging research and clinical service together more closely to solve the problems related to disease discover and medical research, a new imaging informatics infrastructure need to be developed to promote multiple disciplines of medical researchers and clinical physicians working together in a secured and efficient cooperative environment. In this presentation, we outline our work of building Biomedical Imaging Informatics “e-Science” platform integrated with high performance image sharing, collaborating and computing to support multi-disciplines translational biomedical imaging research in multiple affiliated hospitals and academic institutions in Shanghai.

More and more image informatics researchers and engineers are considering to re-construct imaging and informatics infrastructure or to build new framework to enable multiple disciplines of medical researchers, clinical physicians and biomedical engineers working together in a secured, efficient, and transparent cooperative environment. In this presentation, we show an outline and our preliminary design work of building an e-Science platform for biomedical imaging and informatics research and application in Shanghai. We will present our consideration and strategy on designing this platform, and preliminary results. We also will discuss some challenges and solutions in building this platform.

In this study, we report bulk heterojunction solar cells using hybrid heterojunction nanorods as photoactive material. The core–shell nanorods are obtained via self-assembly of low band gap p-type oligomers onto ZnO nanorod surfaces. This produces highly soluble donor–acceptor nanostructures that feature a grafted p-type semiconducting monolayer with a band gap of 2.1 eV. The solution processing of the coaxial nanorods into thin films leads to bulk heterojunctions of particularly large donor–acceptor interfaces. Importantly by simple processing donor domains smaller than typical exciton diffusion length of organic semiconductors are obtained which guaranties efficient exciton dissociation. The corresponding solar cells reveal that the hydrid nanorod layers form efficient interpenetrated networks which lead to external quantum efficiency of 20% at the absorption maximum λmax = 498 nm. Although the donor domains of these hybrid bulk heterojunction are constituted by monolayers, transient absorption spectros...

The present study was designed to evaluate the clinical outcome of using extracorporeal shock wave lithotripsy (ESWL) in the treatment of ureteric calculi and to establish a predictive model for the stone-free rate in patients receiving the treatment. A total of 831 patients with ureteric calculi were accepted in this study. Several parameters, including stone site, stone number, stone size, history of urolithiasis, renal colic, hydronephrosis, and double-J ureteric stent, were analyzed using univariate and multivariate analyses. A prediction model was established based on the logistic regression analysis of the significant factors, and the goodness-of-fit of the model was evaluated by employing the Hosmer–Lemeshow test. At a 3-month follow-up after ESWL treatment, the overall stone-free rate was 96.8% (804/831) with no serious complications being found, while the treatment failed in 3.2% (27/831) of the patients. Five factors, including stone number, stone size, history of urolithiasis, renal colic, and double-J ureteric stent contributed significantly to the clinical outcome of the ESWL treatment. The prediction model had a sensitivity and overall accuracy of 99.8 and 96.9%, respectively. The results show that ESWL remains an effective method for treating ureteric calculi. The prediction model established in this study could be used as a method for estimating prognosis in patients following ESWL treatment.

Polyunsaturated fatty acids (PUFAs) are important components of infant and adult nutrition because they serve as structural elements of cell membranes. Fatty acid desaturases are responsible for the insertion of double bonds into pre-formed fatty acid chains in reactions that require oxygen and reducing equivalents. In this study, the genome-wide characterization of the fatty acid desaturases from seven eukaryotic photosynthetic microalgae was undertaken according to the conserved histidine-rich motifs and phylogenetic profiles. Analysis of these genomes provided insight into the origin and evolution of the pathway of fatty acid biosynthesis in eukaryotic plants. In addition, the candidate enzyme from Chlamydomonas reinhardtii with the highest similarity to the microsomal delta 12 desaturase of Chlorella vulgaris was isolated, and its function was verified by heterologous expression in yeast (Saccharomyces cerevisiae).

IHE XDS-I profile proposes an architecture model for cross-enterprise medical image sharing, but there are only a few clinical implementations reported. Here, we investigate three pilot studies based on the IHE XDS-I profile to see whether we can use this architecture as a foundation for image sharing solutions in a variety of health-care settings. The first pilot study was image sharing for cross-enterprise health care with federated integration, which was implemented in Huadong Hospital and Shanghai Sixth People's Hospital within the Shanghai Shen-Kang Hospital Management Center; the second pilot study was XDS-I-based patient-controlled image sharing solution, which was implemented by the Radiological Society of North America (RSNA) team in the USA; and the third pilot study was collaborative imaging diagnosis with electronic health-care record integration in regional health care, which was implemented in two districts in Shanghai. In order to support these pilot studies, we designed and developed new image access methods, components, and data models such as RAD-69/WADO hybrid image retrieval, RSNA clearinghouse, and extension of metadata definitions in both the submission set and the cross-enterprise document sharing (XDS) registry. We identified several key issues that impact the implementation of XDS-I in practical applications, and conclude that the IHE XDS-I profile is a theoretically good architecture and a useful foundation for medical image sharing solutions across multiple regional health-care providers.

We demonstrate an enhancement of photocurrent in hybrid photovoltaic cells based on nanoparticles of zinc oxide (ZnO) and poly(3-hexylthiophene) (P3HT), through molecular interface modification with and without cis-bis(4,4′-dicarboxy-2,2′bipyridine) ruthenium (II) (N3-dye) and α-Sexithiophen-2-yl-phosphonic Acid (6TP) as interface modifiers. We identify the formation of long-lived polarons at P3HT:ZnO interface by means of quasi-steady-state photoinduced absorption (PIA) spectroscopy. Furthermore, by probing the pump-modulation-frequency-dependent PIA signal, we find that P3HT:ZnO-N3 and P3HT:ZnO-6TP exhibit more sharply decaying density with increasing modulation frequency, which is indicative of a longer average lifetime, approximating 1 ms as opposed to ∼0.2 ms without ZnO surface modification. This highlights the importance of the molecular interface modification in the steady-state polaron dynamics in hybrid solar cells.

The voltage produced by an excitonic solar cell, such as an organic or a hybrid organic/inorganic solar cell is limited by the difference in potential energy between the state occupied by the electron in the acceptor (conduction band minimum (CBM)/lowest unoccupied molecular orbital) and that occupied by the hole in the donor (valence band maximum/highest occupied molecular orbital). Calcium doping of sol-gel ZnO has been used to change the electron affinity of the ZnO acceptor in ZnO/poly(3-hexyl thiophene) hybrid solar cells. The band gap of the mixed oxide system increases with Ca fraction, with most of this attributable to movement of the conduction band minimum toward the vacuum, as determined by UV-vis spectroscopy and Kelvin probe. In planar bilayer cells using Zn0.9Ca0.1O as the acceptor, the open circuit voltage can be increased by 0.24 V, and the efficiency doubled compared to devices using pure ZnO.