757 research outputs found

    Fingerprints of Multiple Electron Scatterings in Single-Layer Graphene

    Get PDF
    The electrons in graphene exhibit unusual behaviours, which can be described by massless Dirac quasiparticles. Understanding electron scattering in graphene has been of significant importance for its future application in electronic devices because electron scattering determines electrical properties such as resistivity and electron transport. There are two types of electron scatterings in graphene: intervalley scattering and intravalley scattering. In single-layer graphene, to date, it has been difficult to observe intravalley scattering because of the suppression of backscattering resulting from the chiral nature of the electrons in graphene. Here, we report the multiple electron scattering behaviours in single-layer graphene on a metallic substrate. By applying one- and two-dimensional Fourier transforms to maps of the local density of states, we can distinguish individual scattering processes from complex interference patterns. These techniques enable us to provide direct evidence of intravalley scattering, revealing a linear dispersion relation with a Fermi velocity of ???7.4 ?? 105 m/s.open

    DBTGR: a database of tunicate promoters and their regulatory elements

    Get PDF
    The high similarity of tunicates and vertebrates during their development coupled with the transparency of tunicate larvae, their well-studied cell lineages and the availability of simple and efficient transgenesis methods makes of this subphylum an ideal system for the investigation of vertebrate physiological and developmental processes. Recently, the sequencing of two different Ciona genomes has lead to the identification of numerous genes. In order to better understand the regulation of these genes, a database was created containing information on regulation of tunicate genes collected from literature. It includes for instance information regarding the minimal promoter length, the transcription factors involved and their binding sites, as well as the localization of the gene expression. Additionally, binding sites for characterized transcription factors were predicted based on published in vitro recognition sites. Comparison of the promoters of homologous genes in different species is also provided to allow identification of conserved cis elements. At the time of writing, information about 184 promoters, containing 73 identified binding sites and >2000 newly predicted binding sites is available. This database is accessible at

    WoLF PSORT: protein localization predictor

    Get PDF
    WoLF PSORT is an extension of the PSORT II program for protein subcellular location prediction. WoLF PSORT converts protein amino acid sequences into numerical localization features; based on sorting signals, amino acid composition and functional motifs such as DNA-binding motifs. After conversion, a simple k-nearest neighbor classifier is used for prediction. Using html, the evidence for each prediction is shown in two ways: (i) a list of proteins of known localization with the most similar localization features to the query, and (ii) tables with detailed information about individual localization features. For convenience, sequence alignments of the query to similar proteins and links to UniProt and Gene Ontology are provided. Taken together, this information allows a user to understand the evidence (or lack thereof) behind the predictions made for particular proteins. WoLF PSORT is available at wolfpsort.or

    Resonant two-photon ionization and laser induced fluorescence spectroscopy of jet-cooled adenine

    Get PDF
    Resonant two-photon ionization (R2PI) and laser induced fluorescence (LIF) techniques were used to obtain the electronic spectra of the jet-cooled DNA base adenine. The spectrum consisted of two bands of the n??* and ????* characters. The vibronic mixing between the two states resulted in the broad absorption whose onset was located 1100 cm -1 above the n??* origin. The presence of these electronically states revealed the presence of vibronic mixing.open12813

    Removal of Rectal Foreign Bodies Using Tenaculum Forceps Under Endoscopic Assistance

    Get PDF
    The incidence of rectal foreign bodies is increasing by the day, though not as common as that of upper gastrointestinal foreign bodies. Various methods for removal of foreign bodies have been reported. Removal during endoscopy using endoscopic devices is simple and safe, but if the foreign body is too large to be removed by this method, other methods are required. We report two cases of rectal foreign body removal by a relatively simple and inexpensive technique. A 42-year-old man with a vibrator in the rectum was admitted due to inability to remove it by himself and various endoscopic methods failed. Finally, the vibrator was removed successfully by using tenaculum forceps under endoscopic assistance. Similarly, a 59-year-old man with a carrot in the rectum was admitted. The carrot was removed easily by using the same method as that in the previous case. The use of tenaculum forceps under endoscopic guidance may be a useful method for removal of rectal foreign bodies

    Exosomes from Human Adipose Tissue-Derived Mesenchymal Stem Cells Promote Epidermal Barrier Repair by Inducing de Novo Synthesis of Ceramides in Atopic Dermatitis.

    Get PDF
    Atopic dermatitis (AD) is a multifactorial, heterogeneous disease associated with epidermal barrier disruption and intense systemic inflammation. Previously, we showed that exosomes derived from human adipose tissue-derived mesenchymal stem cells (ASC-exosomes) attenuate AD-like symptoms by reducing multiple inflammatory cytokine levels. Here, we investigated ASC-exosomes' effects on skin barrier restoration by analyzing protein and lipid contents. We found that subcutaneous injection of ASC-exosomes in an oxazolone-induced dermatitis model remarkably reduced trans-epidermal water loss, while enhancing stratum corneum (SC) hydration and markedly decreasing the levels of inflammatory cytokines such as IL-4, IL-5, IL-13, TNF-α, IFN-γ, IL-17, and TSLP, all in a dose-dependent manner. Interestingly, ASC-exosomes induced the production of ceramides and dihydroceramides. Electron microscopic analysis revealed enhanced epidermal lamellar bodies and formation of lamellar layer at the interface of the SC and stratum granulosum with ASC-exosomes treatment. Deep RNA sequencing analysis of skin lesions demonstrated that ASC-exosomes restores the expression of genes involved in skin barrier, lipid metabolism, cell cycle, and inflammatory response in the diseased area. Collectively, our results suggest that ASC-exosomes effectively restore epidermal barrier functions in AD by facilitating the de novo synthesis of ceramides, resulting in a promising cell-free therapeutic option for treating AD

    Dynamic Temporal Change of Cerebral Microbleeds: Long-Term Follow-Up MRI Study

    Get PDF
    Background: Cerebral microbleeds (MBs) are understood as an important radiologic marker of intracerebral hemorrhage. We sought to investigate the temporal changes of MBs and clinical factors associated with the changes using long-term follow-up MRI. Methods/Principal Findings: From October 2002 to July 2006, we prospectively enrolled patients with stroke or transient ischemic attack, and followed-up their brain MRIs with an interval.12 mo. We compared demographic factors, vascular risk factors, laboratory findings, and radiologic factors according to the presence or changes of MBs. A total of 224 patients successfully completed the follow-up examinations (mean, 27 months). Newly developed MBs were noted in 10 patients (6.8%) among those without MBs at baseline (n = 148), and in those with MBs at baseline (n = 76), the MB count had decreased in 11 patients (14.5%), and increased in 41 patients (53.9%). The estimated annual rate of change of MB numbers was 0.80 lesions per year in all patients, a value which became greater in those patients who exhibited MBs at baseline (MBs$5, 5.43 lesions per year). Strokes due to small vessel occlusion and intracerebral hemorrhage, as well as white matter lesions were independently associated with an increased MB count, whereas the highest quartile of low-density lipoprotein (LDL) cholesterol was associated with a decreased MB count. Conclusion: During the follow-up period, most of MBs showed dynamic temporal change. Symptomatic or asymptomati

    Podocytic PKC-Alpha Is Regulated in Murine and Human Diabetes and Mediates Nephrin Endocytosis

    Get PDF
    Background: Microalbuminuria is an early lesion during the development of diabetic nephropathy. The loss of high molecular weight proteins in the urine is usually associated with decreased expression of slit diaphragm proteins. Nephrin, is the major component of the glomerular slit diaphragm and loss of nephrin has been well described in rodent models of experimental diabetes as well as in human diabetic nephropathy. Methodology/Principal Findings: In this manuscript we analyzed the role of PKC-alpha (PKCa) on endocytosis of nephrin in podocytes. We found that treatment of diabetic mice with a PKCa-inhibitor (GÖ6976) leads to preserved nephrin expression and reduced proteinuria. In vitro, we found that high glucose stimulation would induce PKCa protein expression in murine and human podocytes. We can demonstrate that PKCa mediates nephrin endocytosis in podocytes and that overexpression of PKCa leads to an augmented endocytosis response. After PKC-activation, we demonstrate an inducible association of PKCa, PICK1 and nephrin in podocytes. Moreover, we can demonstrate a strong induction of PKCa in podocytes of patients with diabetic nephropathy. Conclusions/Significance: We therefore conclude that activation of PKCa is a pathomechanistic key event during the development of diabetic nephropathy. PKCa is involved in reduction of nephrin surface expression and therefore PKC
    corecore