654 research outputs found

    Tactile based robotic skills for cable routing operations

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    This paper proposes a set of tactile based skills to perform robotic cable routing operations for deformable linear objects (DLOs) characterized by considerable stiffness and constrained at both ends. In particular, tactile data are exploited to reconstruct the shape of the grasped portion of the DLO and to estimate the future local one. This information is exploited to obtain a grasping configuration aligned to the local shape of the DLO, starting from a rough initial grasping pose, and to follow the DLO's contour in the three-dimensional space. Taking into account the distance travelled along the arc length of the DLO, the robot can detect the cable segments that must be firmly grasped and inserted in intermediate clips, continuing then to slide along the contour until the next DLO's portion, that has to be clipped, is reached. The proposed skills are experimentally validated with an industrial robot on different DLOs in several configurations and on a cable routing use case

    Electrochemical synthesis of carbon quantum dots

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    Carbon quantum dots (CDs) are “small” carbon nanostructures with excellent photoluminescence properties, together with low-toxicity, high biocompatibility, excellent dispersibility in water as well as organic solvents. Due to their characteristics, CDs have been studied for a plethora of applications as biosensors, luminescent probes for photodynamic and photothermal therapy, fluorescent inks and many more. Moreover, the possibility to obtain carbon dots from biomasses and/or organic waste has strongly promoted the interest in this class of carbon-based nanoparticles, having a promising impact in the view of circular economy and sustainable processes. Within this context, electrochemistry proved to be a green, practical, and efficient method for the synthesis of high-quality CDs, with the possibility to fine-tune their characteristics by changing operational parameters. This review outlines the principal and most recent advances in the electrochemical synthesis of CDs, focusing on the electrochemical set-up optimization

    Organic electrochemistry: Synthesis and functionalization of β-lactams in the twenty-first century

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    Organic electrochemistry is a technique that allows for the heterogeneous redox reactions avoiding both the use of stoichiometric amounts of redox reagents and the resulting formation of stoichiometric by-pro- ducts. In fact, the redox reagent in these reactions is the electron, which is naturally eco-friendly and pro- duces no side compounds. It is therefore quite obvious that electrochemistry can be classified as a “green” tech- nology. The use of this methodology in the synthesis of β-lactams is not a novelty, but the growing interest in this class of biologically active compounds, due to the dis- covery of new fields of application (after a moment of decrease in interest due to antibiotic resistance) has been a stimulus for the search for more efficient electro- chemical ways to synthesize and transform β-lactams. Thus, this review deals with the twenty-first-century applications of electroorganic technique to the chemistry of β-lactams, by analyzing first the syntheses classified by the type of reactions (cyclization, cycloaddition, etc.) and then by manipulating the β-lactam structure, using it as a synthon. Lastly, the importance of this technique is demonstrated by a study of a pilot plant scale reduction of a cephalosporanic acid derivative to a commercially important antibiotic

    Reaction of Electrogenerated Cyanomethyl Anion with Cyclohexylisocyanate: Synthesis of N-(cyclohexylcarbamoyl) acetamide. An Unexpected Product

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    The contamination with water of the cathodic ACN-Et4NBF4 solution gave us the opportunity to investigate alkyl isocyanate reactivity toward electrogenerated anions. The cathodic reduction of a ACN-Et4NBF4 solution led to the formation of both hydroxide and cyanomethyl anions. The reaction of the catholyte with cyclohexylisocyanate led to the exclusive formation of acetamidated product, with no traces of cyanomethylated one. On the contrary, when reacting with benzaldehyde only the cyanomethylated was isolated. Considering that the acetamidated product of benzaldehyde is reported to be unstable (thus its formation cannot be excluded), various experiments were carried out in order to understand the anomalous reactivity of cyclohexylisocyanate. Moreover, computational analysis allowed to state the higher stability of acetamidated product with respect to the cyanomethylated one. The possibility of a concerted reaction, instead of acetamide anion formation prior to the reaction, is still an open question

    Motor, epileptic, and developmental phenotypes in genetic disorders affecting G protein coupled receptors-cAMP signaling

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    Over the last years, a constantly increasing number of genetic diseases associated with epilepsy and movement disorders have been recognized. An emerging group of conditions in this field is represented by genetic disorders affecting G-protein-coupled receptors (GPCRs)-cAMP signaling. This group of postsynaptic disorders includes genes encoding for proteins highly expressed in the central nervous system and involved in GPCR signal transduction and cAMP production (e.g., GNAO1, GNB1, ADCY5, GNAL, PDE2A, PDE10A, and HPCA genes). While the clinical phenotype associated with ADCY5 and GNAL is characterized by movement disorder in the absence of epilepsy, GNAO1, GNB1, PDE2A, PDE10A, and HPCA have a broader clinical phenotype, encompassing movement disorder, epilepsy, and neurodevelopmental disorders. We aimed to provide a comprehensive phenotypical characterization of genetic disorders affecting the cAMP signaling pathway, presenting with both movement disorders and epilepsy. Thus, we reviewed clinical features and genetic data of 203 patients from the literature with GNAO1, GNB1, PDE2A, PDE10A, and HPCA deficiencies. Furthermore, we delineated genotype-phenotype correlation in GNAO1 and GNB1 deficiency. This group of disorders presents with a highly recognizable clinical phenotype combining distinctive motor, epileptic, and neurodevelopmental features. A severe hyperkinetic movement disorder with potential life-threatening exacerbations and high susceptibility to a wide range of triggers is the clinical signature of the whole group of disorders. The existence of a distinctive clinical phenotype prompting diagnostic suspicion and early detection has relevant implications for clinical and therapeutic management. Studies are ongoing to clarify the pathophysiology of these rare postsynaptic disorders and start to design disease-specific treatments

    New techniques versus standard mapping for sentinel lymph node biopsy in breast cancer: a systematic review and meta-analysis

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    : New tracers for sentinel lymph node biopsy (SLNB), as indocyanine green (ICG), superparamagnetic iron oxide (SPIO) and micro bubbles, have been recently introduced in clinical practice showing promising but variable results. We reviewed the available evidence comparing these new techniques with the standard tracers to evaluate their safety. To identify all available studies, a systematic search was performed in all electronic databases. Data regarding sample size, mean number of SLN harvested for patient, number of metastatic SLN and SLN identification rate of all studies were extracted. No significant differences were found in terms of SLNs identification rates between SPIO, RI and BD but with a higher identification rate with the use of ICG. No significant differences were also found for the number of metastatic lymph nodes identified between SPIO, RI and BD and the mean number of SLNs identified between SPIO and ICG versus conventional tracers. A statistically significant differences in favor of ICG was reported for the comparison between ICG and conventional tracers for the number of metastatic lymph nodes identified. Our meta-analysis demonstrates that the use of both ICG and SPIO for the pre-operative mapping of sentinel lymph nodes in breast cancer treatment is adequately effective

    An insight into the reactivity of the electrogenerated radical cation of caffeine

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    Controlled potential electrolyses of caffeine (CAF) were carried out at a Pt electrode in undried acetonitrile (ACN) and ACN-H2O and the products of the anodic oxidation were analyzed by HPLC-PDA-ESI-MS/MS. A higher current efficiency occurred in ACN-H2O, but an analogous chromatographic outline was found in both media, evidencing a reactive pathway of the electrogenerated radical cation CAF•+ with water, added or in trace, as nucleophile. No dimeric forms were evidenced, excluding any coupling reactions. Neither was 1,3,7-trimethyluric acid found, reported in the literature as the main oxidative route for CAF in water. Four main chromatographic peaks were evidenced, assigned to four proposed structures on the base of chromatographic and spectral data: a 4,5-diol derivative and an oxazolidin-2-one derivative were assigned as principal oxidation products, supporting a mechanism proposed in a previous work for the primary anodic oxidation of the methylxanthines olefinic C4 = C 5 bond. Two highly polar degradation products were also tentatively assigned, that seemed generating along two different pathways, one opening the imidazolic moiety and another one opening the purinic one
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