102 research outputs found

    Synthesis and characterization of a 2-periodic cadmium-based metal-organic framework: A study on reversible water adsorption

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    A previously-reported cadmium-based two-periodic metal-organic framework [Cd1.5(BTC)(H2O)4.5]n⋅nH2O (CP1) has been re-synthesized, where H3BTC ¼ 1,3,5-benzenetricarboxylic acid. CP1 was characterized with single crystal X-ray diffraction (SCXRD), powder X-ray diffraction (PXRD) followed by various thermal analyses such as thermogravimetric analysis (TGA), hot stage microscopy (HSM) and differential scanning calorimetry (DSC). CP1 is composed of 2-periodic layers, which are interdigitated. Heating can effectively remove the uncoordinated and coordinated water molecules resulting in an amorphous product CP1′. The original framework can be regenerated by readsorption of water from the atmosphere, indicating that the dehydration is reversibl

    Optimal task positioning in multi-robot cells, using nested meta-heuristic swarm algorithms

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    Abstract Process planning of multi-robot cells is usually a manual and time consuming activity, based on trials-and-errors. A co-manipulation problem is analysed, where one robot handles the work-piece and one robot performs a task on it and a method to find the optimal pose of the work-piece is proposed. The method, based on a combination of Whale Optimization Algorithm and Ant Colony Optimization algorithm, minimize a performance index while taking into account technological and kinematics constraints. The index evaluates process accuracy considering transmission elasticity, backslashes and distance from joint limits. Numerical simulations demonstrate the method robustness and convergence

    Estrogen Receptor β Exerts Tumor Repressive Functions in Human Malignant Pleural Mesothelioma via EGFR Inactivation and Affects Response to Gefitinib

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    BACKGROUND: The role of estrogen and estrogen receptors in oncogenesis has been investigated in various malignancies. Recently our group identified estrogen receptor beta (ERβ) expression as an independent prognostic factor in the progression of human Malignant Pleural Mesothelioma (MMe), but the underlying mechanism by which ERβ expression in tumors determines clinical outcome remains largely unknown. This study is aimed at investigating the molecular mechanisms of ERβ action in MMe cells and disclosing the potential translational implications of these results. METHODS: We modulated ERβ expression in REN and MSTO-211H MMe cell lines and evaluated cell proliferation and EGF receptor (EGFR) activation. RESULTS: Our data indicate that ERβ knockdown in ER positive cells confers a more invasive phenotype, increases anchorage independent proliferation and elevates the constitutive activation of EGFR-coupled signal transduction pathways. Conversely, re-expression of ERβ in ER negative cells confers a more epithelioid phenotype, decreases their capacity for anchorage independent growth and down-modulates proliferative signal transduction pathways. We identify a physical interaction between ERβ, EGFR and caveolin 1 that results in an altered internalization and in a selective reduced activation of EGFR-coupled signaling, when ERβ is over-expressed. We also demonstrate that differential expression of ERβ influences MMe tumor cell responsiveness to the therapeutic agent: Gefitinib. CONCLUSIONS: This study describes a role for ERβ in the modulation of cell proliferation and EGFR activation and provides a rationale to facilitate the targeting of a subgroup of MMe patients who would benefit most from therapy with Gefitinib alone or in combination with Akt inhibitors

    Expression Levels of Some Antioxidant and Epidermal Growth Factor Receptor Genes in Patients with Early-Stage Non-Small Cell Lung Cancer

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    This study was aimed at: (i) investigating the expression profiles of some antioxidant and epidermal growth factor receptor genes in cancerous and unaffected tissues of patients undergoing lung resection for non-small cell lung cancer (NSCLC) (cross-sectional phase), (ii) evaluating if gene expression levels at the time of surgery may be associated to patients' survival (prospective phase). Antioxidant genes included heme oxygenase 1 (HO-1), superoxide dismutase-1 (SOD-1), and -2 (SOD-2), whereas epidermal growth factor receptor genes consisted of epidermal growth factor receptor (EGFR) and v-erb-b2 erythroblastic leukaemia viral oncogene homolog 2 (HER-2). Twenty-eight couples of lung biopsies were obtained and gene transcripts were quantified by Real Time RT-PCR. The average follow-up of patients lasted about 60 months. In the cancerous tissues, antioxidant genes were significantly hypo-expressed than in unaffected tissues. The HER-2 transcript levels prevailed in adenocarcinomas, whereas EGFR in squamocellular carcinomas. Patients overexpressing HER-2 in the cancerous tissues showed significantly lower 5-year survival than the others

    Multimodal imaging for clinical target volume definition in prone whole-breast irradiation: a single institution experience

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    Aim: The aim was identification of reference structures for breast clinical target volume (CTV) in prone position, throughout image fusion process. Materials & methods: We analyzed breast glandular tissue distribution in 20 diagnostic MRIs, referring to structures reported in ESTRO guidelines for supine irradiation. The volume containing breast glandular tissue in all cases was defined as MRI prone CTV (MRIpCTV). Then in ten subsequent patients planned for prone irradiation, MRI and computed tomography (CT) simulation was acquired. MRIpCTV was defined followed by our findings and transferred to CT for definitive delineation. Results: MRIpCTV was defined by the caudal edge of clavicular head, 3 mm above inframammary fold, by the medial thoracic artery, by a plane passing through the lateral surface of pectoralis muscles, by the anterior surface of pectoralis muscles and 3 mm from the skin. Deformed CTV was consistent with anatomy on CT; the limits chosen for MRIpCTV fit adequately also for CT. Conclusion: Prone irradiation is an alternative set up for selected cases, so the sample is very small. However, our suggestions could be of aid in defining prone CTV. The good consistency between MRI and CT seems to confirm that MRI may be unnecessary in routine practice

    Role for Chromatin Remodeling Factor Chd1 in Learning and Memory

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    Precise temporal and spatial regulation of gene expression in the brain is a prerequisite for cognitive processes such as learning and memory. Epigenetic mechanisms that modulate the chromatin structure have emerged as important regulators in this context. While posttranslational modification of histones or the modification of DNA bases have been examined in detail in many studies, the role of ATP-dependent chromatin remodeling factors (ChRFs) in learning- and memory-associated gene regulation has largely remained obscure. Here we present data that implicate the highly conserved chromatin assembly and remodeling factor Chd1 in memory formation and the control of immediate early gene (IEG) response in the hippocampus. We used various paradigms to assess short-and long-term memory in mice bearing a mutated Chd1 gene that gives rise to an N-terminally truncated protein. Our data demonstrate that the Chd1 mutation negatively affects long-term object recognition and short- and long-term spatial memory. We found that Chd1 regulates hippocampal expression of the IEG early growth response 1 (Egr1) and activity-regulated cytoskeleton-associated (Arc) but not cFos and brain derived neurotrophic factor (Bdnf), because the Chd1-mutation led to dysregulation of Egr1 and Arc expression in naive mice and in mice analyzed at different stages of object location memory (OLM) testing. Of note, Chd1 likely regulates Egr1 in a direct manner, because chromatin immunoprecipitation (ChIP) assays revealed enrichment of Chd1 upon stimulation at the Egr1 genomic locus in the hippocampus and in cultured cells. Together these data support a role for Chd1 as a critical regulator of molecular mechanisms governing memory-related processes, and they show that this function involves the N-terminal serine-rich region of the protein

    Counting neutrons with a commercial S-CMOS camera

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    It is possible to detect individual flashes from thermal neutron impacts in a ZnS scintillator using a CMOS camera looking at the scintillator screen, and off line image processing. Some preliminary results indicated that the efficiency of recognition could be improved by optimizing the light collection and the image processing. We will report on this ongoing work which is a result from the collaboration between ESS Bilbao and the ILL. The main progress to be reported is situated on the level of the on-line treatment of the imaging data. If this technology is to work on a genuine scientific instrument, it is necessary that all the processing happens on line, to avoid the accumulation of large amounts of image data to be analyzed off line. An FPGA-based real-time full-deca mode VME-compatible CameraLink board has been developed at the SCI of the ILL, which is able to manage the data flow from the camera and convert it in a reasonable “neutron impact” data flow like from a usual neutron counting detector. The main challenge of the endeavor is the optical light collection from the scintillator. While the light yield of a ZnS scintillator is a priori rather important, the amount of light collected with a photographic objective is small. Different scintillators and different light collection techniques have been experimented with and results will be shown for different setups improving upon the light recuperation on the camera sensor. Improvements on the algorithm side will also be presented. The algorithms have to be at the same time efficient in their recognition of neutron signals, in their rejection of noise signals (internal and external to the camera) but also have to be simple enough to be easily implemented in the FPGA. The path from the idea of detecting individual neutron impacts with a CMOS camera to a practical working instrument detector is challenging, and in this paper we will give an overview of the part of the road that has already been walked

    Contrasting properties of particle-particle and hole-hole excitations in ²⁰⁶Tl and ²¹⁰Bi nuclei

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    A complete-spectroscopy investigation of low-lying, low-spin states in the one-proton-hole and one-neutron-hole nucleus 206Tl has been performed by using thermal neutron capture and γ-coincidence technique with the FIPPS Ge array at ILL Grenoble. The new experimental results, together with data for the one-proton-particle and one-neutron-particle nucleus 210Bi (taken from a previous study done at ILL in the EXILL campaign), allowed for an extensive comparison with predictions of shell-model calculations performed with realistic interactions. No phenomenological adjustments were introduced in the calculations. In 210Bi, state energies, transition multipolarities and decay branchings agree well with theory for the three well separated multiplets of states which dominate the low-lying excitations. On the contrary, in 206Tl significant discrepancies are observed: in the same energy region, six multiplets were identified, with a significant mixing among them being predicted, as a consequence of the smaller energy separation between the active orbitals. The discrepancies in 206Tl are attributed to the larger uncertainties in the determination of the off-diagonal matrix elements of the realistic shell-model interaction with respect to the calculated diagonal matrix elements, the only ones playing a major role in the case of 210Bi. The work points to the need of more advanced approaches in the construction of the realistic interactions

    The mutable nature of particle-core excitations with spin in the one-valence-proton nucleus ¹³³Sb

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    The γ-ray decay of excited states of the one-valence-proton nucleus ¹³³Sb has been studied using cold-neutron induced fission of ²³⁵U and ²⁴¹Pu targets, during the EXILL campaign at the ILL reactor in Grenoble. By using a highly efficient HPGe array, coincidences between γ-rays prompt with the fission event and those delayed up to several tens of microseconds were investigated, allowing to observe, for the first time, high-spin excited states above the 16.6 μs isomer. Lifetimes analysis, performed by fast-timing techniques with LaBr₃(Ce) scintillators, revealed a difference of almost two orders of magnitude in B(M1) strength for transitions between positive-parity medium-spin yrast states. The data are interpreted by a newly developed microscopic model which takes into account couplings between core excitations (both collective and non-collective) of the doubly magic nucleus ¹³²Sn and the valence proton, using the Skyrme effective interaction in a consistent way. The results point to a fast change in the nature of particle-core excitations with increasing spin
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