Solid-State Protein Junctions:Cross-Laboratory Study Shows Preservation of Mechanism at Varying Electronic Coupling

Successful integration of proteins in solid-state electronics requires contacting them in a non-invasive fashion, with a solid conducting surface for immobilization as one such contact. The contacts can affect and even dominate the measured electronic transport. Often substrates, substrate treatments, protein immobilization, and device geometries differ between laboratories. Thus the question arises how far results from different laboratories and platforms are comparable and how to distinguish genuine protein electronic transport properties from platform-induced ones. We report a systematic comparison of electronic transport measurements between different laboratories, using all commonly used large-area schemes to contact a set of three proteins of largely different types. Altogether we study eight different combinations of molecular junction configurations, designed so that Ageo of junctions varies from 105 to 10−3 μm2. Although for the same protein, measured with similar device geometry, results compare reasonably well, there are significant differences in current densities (an intensive variable) between different device geometries. Likely, these originate in the critical contact-protein coupling (∼contact resistance), in addition to the actual number of proteins involved, because the effective junction contact area depends on the nanometric roughness of the electrodes and at times, even the proteins may increase this roughness. On the positive side, our results show that understanding what controls the coupling can make the coupling a design knob. In terms of extensive variables, such as temperature, our comparison unanimously shows the transport to be independent of temperature for all studied configurations and proteins. Our study places coupling and lack of temperature activation as key aspects to be considered in both modeling and practice of protein electronic transport experiments

Azospirillum picis sp nov., isolated from discarded tar

A polyphasic taxonomic study was performed on a pink-coloured unknown bacterium isolated from discarded road tar. Comparative analysis of the 16S rRNA gene sequence demonstrated that the isolate belongs phylogenetically to the genus Azospirillum with Azospirillum, lipoferum, A. melinis and A. rugosum as its closest phylogenetic relatives (96.7, 96.6 and 96.6% similarity to the respective type strains). The generic assignment was confirmed on the basis of chemotaxonomic data, which revealed a fatty acid profile characteristic for the genus Azospirillum, consisting of straight-chain saturated and unsaturated fatty acids, with C(18:1)omega 7c as the major unsaturated non-hydroxylated fatty acid, and C(16:0) 3-OH as the major hydroxylated fatty acid, and a ubiquinone with ten isoprene units (Q-10) as the predominant respiratory quinone. On the basis of both the phenotypic and molecular genetic evidence, it is proposed that the unknown isolate should be classified within a novel species of the genus Azospirillum, for which the name Azospirillum picis sp. nov. is proposed. The type strain is IMMIB TAR-3(T) (=CCUG 55431(T) =DSM 19922(T))

A ferritin-containing nanoconjugate as MRI image-guidance to target Necl-5, a tumor-surface antigen: a potential thermal accelerant for microwave ablation

Purpose: A ferritin-containing nanoparticle conjugated with a target-specific antibody was investigated as a MRI contrast agent for tumor detection. A genetically modified ferritin to markedly improve Fe (III) payload (up to 7,000 Fe ions), was chemically tethered to a monoclonal antibody against rat Nectin-like molecule 5 (Necl-5). Necl-5 is a cell surface glycoprotein that is highly expressed on the cell surface of many common epithelial cancers, including prostate cancer. It was previously demonstrated that this novel nanoconjugate agent exhibited effective in vitro targeting of Necl- 5 expressing tumor cells and exhibited strong MRI contrast characteristics via shortening of T2. Here, we demonstrate that the nanoconjugate-Necl-5 interaction can be exploited to target and detect tumor in vivo by MRI. Procedure: Using an in vivo tumor model (i.e., tumor size 0.5-1 cm, immunodeficient beige/nude/xid mouse, xenograft injection with transformed rat prostate cells), efficacy of the conjugate targeting the tumor was examined. We used two injection strategies, a direct and a tail vein injection (0.8 mg, 300 μL per subject). Pre-injection baseline and postinjection scans were performed with the following spin-echo sequence parameters: Field of view = 90x53mm, reconstruction matrix size = 192x114, slice thickness = 1mm (10 slices), repetition time (TR) = 2070 ms, echo times (TE) = 11-198 ms in 11ms steps (18 echoes), number of averages = 2, acquisition time per scan = 7min 56s. Results: All T2 data obtained were converted to R2 for demonstration purposes (R2 = 1/T2). The tail vein injected conjugate significantly increased R2 response (22.9 ± 5.2 s-1) as compared to control (13.5 ±1.7 s-1) at 4 h. The weaker R2 increase was noted (15.2 ± 2.0 s-1) at 24 h. No notable changes in R2 were observed in surrounding tissues regardless the stages of the measurement. We also measured the initial conjugate kinetics for both injection methods with respect to the ability of targeting the tumor. Direct injection of the nanoconjugate in to the center of the tumor showed a stronger and more rapid increase in R2 than the tail vein injection. Conclusion: The nanoconjugate interacts strongly and selectively in situ with Necl-5 overexpressing tumor cells. Direct injection of the nanoconjugate into the body of the tumor caused a more significant in situ R2 increase in MRI than the tail vein injection. Varying degrees of R2 increase within the tumor mass is likely to represent different distribution patterns of the conjugate, reflective of tumor heterogeneity.Published versio

APLIKASI ZAHIR PADA PERUSAHAAN PERDAGANGAN

Laporan Keuangan merupakan alat komunikasi yang efektif untuk memberikan Informasi mengenai kondisi keuangan perusahaan bagi pemangku kepentingan baik internal maupun eksternal. Pada konteks perusahaan yang terpisah antara pemilik dan pengelola, bagi pemangku kepentingan internal, seperti manajemen dan pegawai perusahaan Laporan Keuangan bermanfaat untuk melaporkan hasil kinerja operasional mereka dalam satu periode akuntansi/satu tahun buku, sebagai dasar penilaian oleh top manajemen atas kinerja manajemen lini menengah dan bawah serta kinerja pegawai. Bagi pemangku kepentingan eksternal, laporan keuangan bermanfaat untuk mendukung pengambilan keputusan antara lain menilai prospek investasi atau kemampuan perusahaan dalam membayar utang atau kewajiban lain. Hal ini membuat kemampuan menyusun laporan keuangan sangat diperlukan bagi pengelola perusahaan, baik pada perusahaan yang terpisah maupun tidak terpisah antara pemilik dan pengelola. Kualitas informasi dalam laporan keuangan sangat dipengaruhi oleh kepatuhan terhadap standar akuntansi dan didukung oleh sistem akuntansi yang handal. Untuk menghasilkan laporan keuangan yang berkualitas dibutuhkan sumber daya manusia yang memahami dan kompeten dalam akuntansi didukung oleh aplikasi yang manfaat dan bermutu. Penyusunan laporan keuangan perusahaan membutuhkan ketelitian yang sangat tinggi, sehingga semakin kompleks semakin besar lingkup usaha, maka semakin membutuhkan upaya yang lebih dalam penyusunnya terlebih ketika dilakukan secara manual. Untuk itu keberadaan aplikasi/software akuntansi sangat membantu mengorganisasikan transaksi ekonomi/bisnis perusahaan