408 research outputs found

    Semi-Automated Data Analysis for Ion-Selective Electrodes and Arrays Using the R Package ISEtools.

    Get PDF
    A new software package, ISEtools, is introduced for use within the popular open-source programming language R that allows Bayesian statistical data analysis techniques to be implemented in a straightforward manner. Incorporating all collected data simultaneously, this Bayesian approach naturally accommodates sensor arrays and provides improved limit of detection estimates, including providing appropriate uncertainty estimates. Utilising >1500 lines of code, ISEtools provides a set of three core functions-loadISEdata, describeISE, and analyseISE- for analysing ion-selective electrode data using the Nikolskii-Eisenman equation. The functions call, fit, and extract results from Bayesian models, automatically determining data structures, applying appropriate models, and returning results in an easily interpretable manner and with publication-ready figures. Importantly, while advanced statistical and computationally intensive methods are employed, the functions are designed to be accessible to non-specialists. Here we describe basic features of the package, demonstrated through a worked environmental application

    Human parietal epithelial cells (PECs) and proteinuria in lupus nephritis: a role for ClC-5, megalin, and cubilin?

    Get PDF
    Background: Parietal epithelial cells are a heterogeneous population of cells located on Bowman’s capsule. These cells are known to internalize albumin with a still undetermined mechanism, although albumin has been shown to induce phenotypic changes in parietal epithelial cells. Proximal tubular cells are the main actors in albumin handling via the macromolecular complex composed by ClC-5, megalin, and cubilin. This study investigated the role of ClC-5, megalin, and cubilin in the parietal epithelial cells of kidney biopsies from proteinuric lupus nephritis patients and control subjects and identified phenotypical changes occurring in the pathological milieu. Methods: Immunohistochemistry and immunofluorescence analyses for ClC-5, megalin, cubilin, ANXA3, podocalyxin, CD24, CD44, HSA, and LTA marker were performed on 23 kidney biopsies from patients with Lupus Nephritis and 9 control biopsies (obtained from nephrectomies for renal cancer). Results: Two sub-populations of hypertrophic parietal epithelial cells ANXA3+/Podocalyxin−/CD44−, both expressing ClC-5, megalin, and cubilin and located at the tubular pole, were identified and characterized: the first one, CD24+/HSA−/LTA− had characteristics of human adult parietal epithelial multipotent progenitors, the second one, CD24−/LTA+/HSA+ committed to become phenotypically proximal tubular cells. The number of glomeruli presenting hypertrophic parietal epithelial cells positive for ClC-5, megalin, and cubilin were significantly higher in lupus nephritis patients than in controls. Conclusions: Our results may provide further insight into the role of hypertrophic parietal epithelial cells located at the tubular pole and their possible involvement in protein endocytosis in lupus nephritis patients. These data also suggest that the presence of hypertrophic parietal epithelial cells in Bowman's capsule represents a potential resource for responding to protein overload observed in other glomerulonephritis

    Vision-Guided Robot Hearing

    Get PDF
    International audienceNatural human-robot interaction (HRI) in complex and unpredictable environments is important with many potential applicatons. While vision-based HRI has been thoroughly investigated, robot hearing and audio-based HRI are emerging research topics in robotics. In typical real-world scenarios, humans are at some distance from the robot and hence the sensory (microphone) data are strongly impaired by background noise, reverberations and competing auditory sources. In this context, the detection and localization of speakers plays a key role that enables several tasks, such as improving the signal-to-noise ratio for speech recognition, speaker recognition, speaker tracking, etc. In this paper we address the problem of how to detect and localize people that are both seen and heard. We introduce a hybrid deterministic/probabilistic model. The deterministic component allows us to map 3D visual data onto an 1D auditory space. The probabilistic component of the model enables the visual features to guide the grouping of the auditory features in order to form audiovisual (AV) objects. The proposed model and the associated algorithms are implemented in real-time (17 FPS) using a stereoscopic camera pair and two microphones embedded into the head of the humanoid robot NAO. We perform experiments with (i)~synthetic data, (ii)~publicly available data gathered with an audiovisual robotic head, and (iii)~data acquired using the NAO robot. The results validate the approach and are an encouragement to investigate how vision and hearing could be further combined for robust HRI

    Imidazoacridinone-dependent lysosomal photodestruction: a pharmacological Trojan horse approach to eradicate multidrug-resistant cancers

    Get PDF
    Multidrug resistance (MDR) remains a primary hindrance to curative cancer therapy. Thus, introduction of novel strategies to overcome MDR is of paramount therapeutic significance. Sequestration of chemotherapeutics in lysosomes is an established mechanism of drug resistance. Here, we show that MDR cells display a marked increase in lysosome number. We further demonstrate that imidazoacridinones (IAs), which are cytotoxic fluorochromes, undergo a dramatic compartmentalization in lysosomes because of their hydrophobic weak base nature. We hence developed a novel photoactivation-based pharmacological Trojan horse approach to target and eradicate MDR cancer cells based on photo-rupture of IA-loaded lysosomes and tumor cell lysis via formation of reactive oxygen species. Illumination of IA-loaded cells resulted in lysosomal photodestruction and restoration of parental cell drug sensitivity. Lysosomal photodestruction of MDR cells overexpressing the key MDR efflux transporters ABCG2, ABCB1 or ABCC1 resulted in 10- to 52-fold lower IC(50) values of various IAs, thereby restoring parental cell sensitivity. Finally, in vivo application of this photodynamic therapy strategy after i.v. injection of IAs in human ovarian tumor xenografts in the chorioallantoic membrane model revealed selective destruction of tumors and their associated vasculature. These findings identify lysosomal sequestration of IAs as an Achilles heel of MDR cells that can be harnessed to eradicate MDR tumor cells via lysosomal photodestruction

    Animal models for aberrations of gonadotropin action

    Get PDF
    During the last two decades a large number of genetically modified mouse lines with altered gonadotropin action have been generated. These mouse lines fall into three categories: the lack-of-function mice, gain-of-function mice, and the mice generated by breeding the abovementioned lines with other disease model lines. The mouse strains lacking gonadotropin action have elucidated the necessity of the pituitary hormones in pubertal development and function of gonads, and revealed the processes from the original genetic defect to the pathological phenotype such as hypo- or hypergonadotropic hypogonadism. Conversely, the strains of the second group depict consequences of chronic gonadotropin action. The lines vary from those expressing constitutively active receptors and those secreting follicle-stimulating hormone (FSH) with slowly increasing amounts to those producing human choriogonadotropin (hCG), amount of which corresponds to 2000-fold luteinizing hormone (LH)/hCG biological activity. Accordingly, the phenotypes diverge from mild anomalies and enhanced fertility to disrupted gametogenesis, but eventually chronic, enhanced and non-pulsatile action of both FSH and LH leads to female and male infertility and/or hyper- and neoplasias in most of the gonadotropin gain-of-function mice. Elevated gonadotropin levels also alter the function of several extra-gonadal tissues either directly or indirectly via increased sex steroid production. These effects include promotion of tumorigenesis in tissues such as the pituitary, mammary and adrenal glands. Finally, the crossbreedings of the current mouse strains with other disease models are likely to uncover the contribution of gonadotropins in novel biological systems, as exemplified by the recent crossbreed of LHCG receptor deficient mice with Alzheimer disease mice

    Jet energy measurement with the ATLAS detector in proton-proton collisions at root s=7 TeV

    Get PDF
    The jet energy scale and its systematic uncertainty are determined for jets measured with the ATLAS detector at the LHC in proton-proton collision data at a centre-of-mass energy of √s = 7TeV corresponding to an integrated luminosity of 38 pb-1. Jets are reconstructed with the anti-kt algorithm with distance parameters R=0. 4 or R=0. 6. Jet energy and angle corrections are determined from Monte Carlo simulations to calibrate jets with transverse momenta pT≥20 GeV and pseudorapidities {pipe}η{pipe}<4. 5. The jet energy systematic uncertainty is estimated using the single isolated hadron response measured in situ and in test-beams, exploiting the transverse momentum balance between central and forward jets in events with dijet topologies and studying systematic variations in Monte Carlo simulations. The jet energy uncertainty is less than 2. 5 % in the central calorimeter region ({pipe}η{pipe}<0. 8) for jets with 60≤pT<800 GeV, and is maximally 14 % for pT<30 GeV in the most forward region 3. 2≤{pipe}η{pipe}<4. 5. The jet energy is validated for jet transverse momenta up to 1 TeV to the level of a few percent using several in situ techniques by comparing a well-known reference such as the recoiling photon pT, the sum of the transverse momenta of tracks associated to the jet, or a system of low-pT jets recoiling against a high-pT jet. More sophisticated jet calibration schemes are presented based on calorimeter cell energy density weighting or hadronic properties of jets, aiming for an improved jet energy resolution and a reduced flavour dependence of the jet response. The systematic uncertainty of the jet energy determined from a combination of in situ techniques is consistent with the one derived from single hadron response measurements over a wide kinematic range. The nominal corrections and uncertainties are derived for isolated jets in an inclusive sample of high-pT jets. Special cases such as event topologies with close-by jets, or selections of samples with an enhanced content of jets originating from light quarks, heavy quarks or gluons are also discussed and the corresponding uncertainties are determined. © 2013 CERN for the benefit of the ATLAS collaboration

    Measurement of the cross-section of high transverse momentum vector bosons reconstructed as single jets and studies of jet substructure in pp collisions at √s = 7 TeV with the ATLAS detector

    Get PDF
    This paper presents a measurement of the cross-section for high transverse momentum W and Z bosons produced in pp collisions and decaying to all-hadronic final states. The data used in the analysis were recorded by the ATLAS detector at the CERN Large Hadron Collider at a centre-of-mass energy of √s = 7 TeV;{\rm Te}{\rm V}andcorrespondtoanintegratedluminosityof and correspond to an integrated luminosity of 4.6\;{\rm f}{{{\rm b}}^{-1}}.ThemeasurementisperformedbyreconstructingtheboostedWorZbosonsinsinglejets.ThereconstructedjetmassisusedtoidentifytheWandZbosons,andajetsubstructuremethodbasedonenergyclusterinformationinthejetcentreofmassframeisusedtosuppressthelargemultijetbackground.ThecrosssectionforeventswithahadronicallydecayingWorZboson,withtransversemomentum. The measurement is performed by reconstructing the boosted W or Z bosons in single jets. The reconstructed jet mass is used to identify the W and Z bosons, and a jet substructure method based on energy cluster information in the jet centre-of-mass frame is used to suppress the large multi-jet background. The cross-section for events with a hadronically decaying W or Z boson, with transverse momentum {{p}_{{\rm T}}}\gt 320\;{\rm Ge}{\rm V}andpseudorapidity and pseudorapidity |\eta |\lt 1.9,ismeasuredtobe, is measured to be {{\sigma }_{W+Z}}=8.5\pm 1.7$ pb and is compared to next-to-leading-order calculations. The selected events are further used to study jet grooming techniques

    Search for pair-produced long-lived neutral particles decaying to jets in the ATLAS hadronic calorimeter in ppcollisions at √s=8TeV

    Get PDF
    The ATLAS detector at the Large Hadron Collider at CERN is used to search for the decay of a scalar boson to a pair of long-lived particles, neutral under the Standard Model gauge group, in 20.3fb−1of data collected in proton–proton collisions at √s=8TeV. This search is sensitive to long-lived particles that decay to Standard Model particles producing jets at the outer edge of the ATLAS electromagnetic calorimeter or inside the hadronic calorimeter. No significant excess of events is observed. Limits are reported on the product of the scalar boson production cross section times branching ratio into long-lived neutral particles as a function of the proper lifetime of the particles. Limits are reported for boson masses from 100 GeVto 900 GeV, and a long-lived neutral particle mass from 10 GeVto 150 GeV

    Search for direct pair production of the top squark in all-hadronic final states in proton-proton collisions at s√=8 TeV with the ATLAS detector

    Get PDF
    The results of a search for direct pair production of the scalar partner to the top quark using an integrated luminosity of 20.1fb−1 of proton–proton collision data at √s = 8 TeV recorded with the ATLAS detector at the LHC are reported. The top squark is assumed to decay via t˜→tχ˜01 or t˜→ bχ˜±1 →bW(∗)χ˜01 , where χ˜01 (χ˜±1 ) denotes the lightest neutralino (chargino) in supersymmetric models. The search targets a fully-hadronic final state in events with four or more jets and large missing transverse momentum. No significant excess over the Standard Model background prediction is observed, and exclusion limits are reported in terms of the top squark and neutralino masses and as a function of the branching fraction of t˜ → tχ˜01 . For a branching fraction of 100%, top squark masses in the range 270–645 GeV are excluded for χ˜01 masses below 30 GeV. For a branching fraction of 50% to either t˜ → tχ˜01 or t˜ → bχ˜±1 , and assuming the χ˜±1 mass to be twice the χ˜01 mass, top squark masses in the range 250–550 GeV are excluded for χ˜01 masses below 60 GeV
    corecore