1,174 research outputs found
Thienothiophene-benzotriazole-based semicrystalline linear copolymers for organic field effect transistors
A series of thienothiophene-benzotriazole-based semicrystalline copolymers, PTTBTz, PTTBTz-F, and PTTBTz-OR, were synthesized by considering chain linearity, planarity and inter-chain packing by virtue of non-covalent attractive interaction. Fluorine and alkoxy substituents were introduced to modulate the intra- and inter-chain coulombic interactions and crystalline ordering. The fluorine and alkoxy-substituted PTTBTz-F and PTTBTz-OR showed pronounced inter-chain packing with edge-on orientation confirmed by UV-vis absorption and X-ray diffraction measurements. The well-resolved diffraction patterns were obtained for PTTBTz-F and PTTBTz-OR, showing (100)similar to(500) inter-lamellar scattering peaks (d-spacing, 17 similar to 18 angstrom) in the out-of-plane direction and a pi-pi stacking peak (d-spacing, 3.5 similar to 4.1 angstrom) in the in-plane direction. Organic field effect transistor (OFET) devices were fabricated with a bottom gate and top contact geometry. PTTBTz-F (mu(h) = 4.49 x 10(-2) cm(2) V-1 s(-1), on/off ratio = 1.13 x 107) and PTTBTz-OR (mu(h) = 8.39 x 10(-3) cm(2) V-1 s(-1), on/off ratio = 2.98 x 104) showed nearly 3 and 2 orders of magnitude higher hole mobility upon annealing at 305 and 260 degrees C, with compared to the unsubstituted PTTBTz.X1165Ysciescopu
Road Damage Detection Acquisition System based on Deep Neural Networks for Physical Asset Management
Research on damage detection of road surfaces has been an active area of
re-search, but most studies have focused so far on the detection of the
presence of damages. However, in real-world scenarios, road managers need to
clearly understand the type of damage and its extent in order to take effective
action in advance or to allocate the necessary resources. Moreover, currently
there are few uniform and openly available road damage datasets, leading to a
lack of a common benchmark for road damage detection. Such dataset could be
used in a great variety of applications; herein, it is intended to serve as the
acquisition component of a physical asset management tool which can aid
governments agencies for planning purposes, or by infrastructure mainte-nance
companies. In this paper, we make two contributions to address these issues.
First, we present a large-scale road damage dataset, which includes a more
balanced and representative set of damages. This dataset is composed of 18,034
road damage images captured with a smartphone, with 45,435 in-stances road
surface damages. Second, we trained different types of object detection
methods, both traditional (an LBP-cascaded classifier) and deep learning-based,
specifically, MobileNet and RetinaNet, which are amenable for embedded and
mobile and implementations with an acceptable perfor-mance for many
applications. We compare the accuracy and inference time of all these models
with others in the state of the art
Genomes of coral dinoflagellate symbionts highlight evolutionary adaptations conducive to a symbiotic lifestyle.
Despite half a century of research, the biology of dinoflagellates remains enigmatic: they defy many functional and genetic traits attributed to typical eukaryotic cells. Genomic approaches to study dinoflagellates are often stymied due to their large, multi-gigabase genomes. Members of the genus Symbiodinium are photosynthetic endosymbionts of stony corals that provide the foundation of coral reef ecosystems. Their smaller genome sizes provide an opportunity to interrogate evolution and functionality of dinoflagellate genomes and endosymbiosis. We sequenced the genome of the ancestral Symbiodinium microadriaticum and compared it to the genomes of the more derived Symbiodinium minutum and Symbiodinium kawagutii and eukaryote model systems as well as transcriptomes from other dinoflagellates. Comparative analyses of genome and transcriptome protein sets show that all dinoflagellates, not only Symbiodinium, possess significantly more transmembrane transporters involved in the exchange of amino acids, lipids, and glycerol than other eukaryotes. Importantly, we find that only Symbiodinium harbor an extensive transporter repertoire associated with the provisioning of carbon and nitrogen. Analyses of these transporters show species-specific expansions, which provides a genomic basis to explain differential compatibilities to an array of hosts and environments, and highlights the putative importance of gene duplications as an evolutionary mechanism in dinoflagellates and Symbiodinium
Interleukin-1β sequesters hypoxia inducible factor 2α to the primary cilium.
BACKGROUND: The primary cilium coordinates signalling in development, health and disease. Previously we have shown that the cilium is essential for the anabolic response to loading and the inflammatory response to interleukin-1β (IL-1β). We have also shown the primary cilium elongates in response to IL-1β exposure. Both anabolic phenotype and inflammatory pathology are proposed to be dependent on hypoxia-inducible factor 2 alpha (HIF-2α). The present study tests the hypothesis that an association exists between the primary cilium and HIFs in inflammatory signalling. RESULTS: Here we show, in articular chondrocytes, that IL-1β-induces primary cilia elongation with alterations to cilia trafficking of arl13b. This elongation is associated with a transient increase in HIF-2α expression and accumulation in the primary cilium. Prolyl hydroxylase inhibition results in primary cilia elongation also associated with accumulation of HIF-2α in the ciliary base and axoneme. This recruitment and the associated cilia elongation is not inhibited by blockade of HIFα transcription activity or rescue of basal HIF-2α expression. Hypomorphic mutation to intraflagellar transport protein IFT88 results in limited ciliogenesis. This is associated with increased HIF-2α expression and inhibited response to prolyl hydroxylase inhibition. CONCLUSIONS: These findings suggest that ciliary sequestration of HIF-2α provides negative regulation of HIF-2α expression and potentially activity. This study indicates, for the first time, that the primary cilium regulates HIF signalling during inflammation
Study of the decays B->D_s1(2536)+ anti-D(*)
We report a study of the decays B -> D_s1(2536)+ anti-D(*), where anti-D(*)
is anti-D0, D- or D*-, using a sample of 657 x 10^6 B anti-B pairs collected at
the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy
e+e- collider. The branching fractions of the decays B+ -> D_s1(2536)+ anti-D0,
B0 -> D_s1(2536)+ D- and B0 -> D_s1(2536)+ D*- multiplied by that of
D_s1(2536)+ -> (D*0K+ + D*+K0) are found to be (3.97+-0.85+-0.56) x 10^-4,
(2.75+-0.62+-0.36) x 10^-4 and (5.01+-1.21+-0.70) x 10^-4, respectively.Comment: 6 pages, 2 figues, submitted to PRD (RC
Evidence for B- -> tau- nu_bar with a Semileptonic Tagging Method
We present a measurement of the decay B- -> tau- nu_bar using a data sample
containing 657 million BB_bar pairs collected at the Upsilon(4S) resonance with
the Belle detector at the KEKB asymmetric-energy e+e- collider. A sample of
BB_bar pairs are tagged by reconstructing one B meson decaying
semileptonically. We detect the B- -> tau- nu_bar candidate in the recoil. We
obtain a signal with a significance of 3.6 standard deviations including
systematic uncertainties, and measure the branching fraction to be Br(B- ->
tau- nu_bar) = [1.54+0.38-0.37(stat)+0.29-0.31(syst)]*10^-4. This result
confirms the evidence for B- -> tau- nu_bar obtained in a previous Belle
measurement that used a hadronic B tagging method.Comment: 7 pages, 3 figures, corrected references, to appear in PRD-R
F-18-AV-1451 PET Imaging in Three Patients with Probable Cerebral Amyloid Angiopathy
Cerebrovascular deposition of amyloid-β, known as cerebral amyloid angiopathy (CAA), is associated with MRI findings of lobar hemorrhage, cerebral microbleeds, and cortical superficial siderosis. Although pathological studies suggest that tau may co-localize with vascular amyloid, this has not yet been investigated in CAA in vivo. Three patients with probable CAA underwent 11C-Pittsburgh Compound B (PiB) PET or 18F-florbetaben PET to evaluate amyloid burden, and 18F-AV-1451 PET to evaluate paired helical filament tau burden. Regions that had cerebral microbleeds or cortical superficial siderosis largely overlapped with those showing increased 18F-AV-1451. Our preliminary study raised the possibility that lobar cerebral microbleeds, and cortical superficial siderosis, which are characteristic markers of vascular amyloid, may be associated with local production of paired helical filament tau
In vivo action of IL-27: reciprocal regulation of Th17 and Treg cells in collagen-induced arthritis
Interleukin (IL)-27 is a novel cytokine of the IL-6/IL-12 family that has been reported to be involved in the pathogenesis of autoimmune diseases and has a pivotal role as both a pro-and anti-inflammatory cytokine. We investigated the in vivo effects of IL-27 on arthritis severity in a murine collagen-induced arthritis (CIA) model and its mechanism of action regarding control of regulatory T (Tregs) and IL-17-producing T helper 17 (Th17) cells. IL-27-Fc-treated CIA mice showed a lower severity of arthritis. IL-17 expression in the spleens was significantly decreased in IL-27-Fc-treated CIA mice compared with that in the CIA model. The Th17 population was decreased in the spleens of IL-27-Fc-treated CIA mice, whereas the CD4(+)CD25(+)Foxp(3+) Treg population increased. In vitro studies revealed that IL-27 inhibited IL-17 production in murine CD4(+) T cells, and the effect was associated with retinoic acid-related orphan receptor gamma T and signal transducer and activator of transcription 3 inhibition. In contrast, fluorescein isothiocyanate-labeled forkhead box P3 (Foxp3) and IL-10 were profoundly augmented by IL-27 treatment. Regarding the suppressive capacity of Treg cells, the proportions of CTLA-4(+) (cytotoxic T-lymphocyte antigen 4), PD-1(+) (programmed cell death protein 1) and GITR(+) (glucocorticoid-induced tumor necrosis factor receptor) Tregs increased in the spleens of IL-27-Fc-treated CIA mice. Furthermore, in vitro differentiated Treg cells with IL-27 exerted a more suppressive capacity on T-cell proliferation. We found that IL-27 acts as a reciprocal regulator of the Th17 and Treg populations in CD4(+) cells isolated from healthy human peripheral blood mononuclear cells (PBMCs), as well as from humans with rheumatoid arthritis (RA) PBMCs. Our study suggests that IL-27 has the potential to ameliorate overwhelming inflammation in patients with RA through a reciprocal regulation of Th17 and Treg cells.open113330sciescopuskc
Mortality among patients with tuberculosis requiring intensive care: a retrospective cohort study
<p>Abstract</p> <p>Background</p> <p>To describe the characteristics of patients with tuberculosis (TB) requiring intensive care and to identify the factors that predicts in-hospital mortality in a city of a developing country with intermediate-to-high TB endemicity.</p> <p>Methods</p> <p>We conducted a retrospective, cohort study, between November 2005 and November 2007. The patients with TB requiring intensive care were included. Predictors of mortality were assessed. The primary outcome was the in-hospital mortality.</p> <p>Results</p> <p>During the study period, 67 patients with TB required intensive care. Of them, 62 (92.5%) had acute respiratory failure and required mechanical ventilation. Forty-four (65.7%) patients died. Coinfection with human immunodeficiency virus was present in 46 (68.7%) patients. Early intensive care unit admission and ventilator-associated pneumonia were independently associated with the in-hospital mortality.</p> <p>Conclusions</p> <p>In this study we found a high mortality rate in TB patients requiring intensive care, especially in those with an early ICU admission.</p
Curcumin Promotes A-beta Fibrillation and Reduces Neurotoxicity in Transgenic Drosophila
The pathology of Alzheimer's disease (AD) is characterized by the presence of extracellular deposits of misfolded and aggregated amyloid-β (Aβ) peptide and intraneuronal accumulation of tangles comprised of hyperphosphorylated Tau protein. For several years, the natural compound curcumin has been proposed to be a candidate for enhanced clearance of toxic Aβ amyloid. In this study we have studied the potency of feeding curcumin as a drug candidate to alleviate Aβ toxicity in transgenic Drosophila. The longevity as well as the locomotor activity of five different AD model genotypes, measured relative to a control line, showed up to 75% improved lifespan and activity for curcumin fed flies. In contrast to the majority of studies of curcumin effects on amyloid we did not observe any decrease in the amount of Aβ deposition following curcumin treatment. Conformation-dependent spectra from p-FTAA, a luminescent conjugated oligothiophene bound to Aβ deposits in different Drosophila genotypes over time, indicated accelerated pre-fibrillar to fibril conversion of Aβ1–42 in curcumin treated flies. This finding was supported by in vitro fibrillation assays of recombinant Aβ1–42. Our study shows that curcumin promotes amyloid fibril conversion by reducing the pre-fibrillar/oligomeric species of Aβ, resulting in a reduced neurotoxicity in Drosophila
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