119 research outputs found

    Logic functions, devices, and circuits based on parametric nonlinear processes

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    Second-harmonic generation and parametric down-conversion processes have been studied as the basis of all-optical logic gates. All possibilities that are obtainable with both the low and high conversion efficiencies of such processes have been analyzed here. XOR and AND gates are also experimentally proven by using 1-ps pulses at 800 nm within a beta-BaB(2)O(4) crystal, reaching conversion efficiencies of as high as 80%. Based on these phenomena, complex algebraic operations are proposed for performing several different logic functionalities particularly concerning network switching and arithmetic calculation

    From Agri-Food Wastes to Polyhydroxyalkanoates through a Sustainable Process

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    The biologically-derived polymers polyhydroxyalkanoates (PHAs) are biodegradable and can be considered a valuable alternative to conventional fossil-based plastics. However, upstream and downstream processes for PHA production are characterized by high energy and chemical consumption and are not economically competitive with petroleum-based polymers. Aiming to improve both the environmental and economical sustainability of PHAs production, in this work, corn straw was used as raw material to obtain a mixture of fermentable sugars after microwave-assisted flash hydrolysis (2 min, 0.01 g/L, 50.7% yield). A mixed microbial culture enriched from dairy industry waste was used for fermentation in a shake flask, allowing us to achieve good poly(hydroxy-butyrate-co-hydroxy-valerate) yields (41.4%, after 72 h of fermentation). A scale-up in a stirred tank bioreactor (3 L) gave higher yields (76.3%, after 96 h), allowing in both cases to achieve a concentration of 0.42 g/L in the fermentation medium. The possibility of producing PHAs from agricultural waste using a mixed microbial culture from the food industry with enabling technologies could make the production of biopolymers more competitive

    Experimental results of the laserwire emittance scanner for LINAC4 at CERN

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    Within the framework of the LHC Injector Upgrade (LIU), the new LINAC4 is currently being commissioned to replace the existing LINAC2 proton source at CERN. After the expected completion at the end of 2016, the LINAC4 will accelerate H- ions to 160 MeV. To measure the transverse emittance of the H- beam, a method based on photo-detachment is proposed. This system will operate using a pulsed laser with light delivered via an optical fibre and subsequently focused through a thin slice of the H- beam. The laser photons have sufficient energy to detach the outer electron and create H0/e- pairs. In a downstream dipole, the created H0 particles are separated from the unstripped H- ions and their distribution is measured with a dedicated detector. By scanning the focused laser across the H- beam, the transverse emittance of the H- beam can be reconstructed. This paper will first discuss the concept, design and simulations of the laserComment: Presented at the International Conference on Laser Applications at Accelerators, LA3NET 2015; Submitted to Nucl. Instr. and Meth. in Phys. Res. section

    Early putamen hypertrophy and ongoing hippocampus atrophy predict cognitive performance in the first ten years of relapsing-remitting multiple sclerosis

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    Background The first years of relapsing-remitting multiple sclerosis (RRMS) constitute the most vulnerable phase for the progression of cognitive impairment (CImp), due to a gradual decrease of compensatory mechanisms. In the first 10 years of RRMS, the temporal volumetric changes of deep gray matter structures must be clarified, since they could constitute reliable cognitive biomarkers for diagnostic, prognostic, and therapeutic purposes. Methods Forty-five cognitively asymptomatic patients with RRMS lasting 64\u200910 years, and with a brain MRI performed in a year from the neuropsychological evaluation (Te-MRI), were included. They performed the Brief International Cognitive Assessment battery for MS. Thirty-one brain MRIs performed in the year of diagnosis (Td-MRI) and 13 brain MRIs of age- and sex-matched healthy controls (HCs) were also included in the study. The relationships between clinical features, cognitive performances, and Te- and Td-MRI volumes were statistically analyzed. Results Cognitively preserved (CP) patients had significantly increased Td-L-putamen (P\u2009=\u20090.035) and Td-R-putamen volume (P\u2009=\u20090.027) with respect to cognitively impaired (CI) ones. CI patients had significantly reduced Te-L-hippocampus (P\u2009=\u20090.019) and Te-R-hippocampus volume (P\u2009=\u20090.042) compared, respectively, with Td-L-hippocampus and Td-R-hippocampus volume. Td-L-putamen volume (P\u2009=\u20090.011) and Te-L-hippocampus volume (P\u2009=\u20090.023) were independent predictors of the Symbol Digit Modalities Test score in all patients (r2\u2009=\u20090.31, F\u2009=\u20096.175, P\u2009=\u20090.001). Conclusion In the first years of RRMS, putamen hypertrophy and hippocampus atrophy could represent promising indices of cognitive performance and reserve, and become potentially useful tools for diagnostic, prognostic, and therapeutic purposes

    rTMS over the human medial parietal cortex impairs online reaching corrections

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    Indirect correlational evidence suggests that the posteromedial sector of the human parietal cortex (area hV6A) is involved in reaching corrections. We interfered with hV6A functions using repetitive transcranial magnetic stimulation (rTMS) while healthy participants performed reaching movements and in-flight adjustments of the hand trajectory in presence of unexpected target shifts. rTMS over hV6A specifically altered action reprogramming, causing deviations of the shifted trajectories, particularly along the vertical dimension (i.e., distance). This study provides evidence of the functional relevance of hV6A in action reprogramming while a sudden event requires a change in performance and shows that hV6A also plays a role in state estimation during reaching. These findings are in line with neurological data showing impairments in actions performed along the distance dimension when lesions occur in the dorsal posterior parietal cortex

    Thyroglobulin measurement in the washout of fine needle aspirates for the diagnosis of suspicious cervical lymph nodes

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    Ultrasound-guided fine-needle aspiration cytology (FNAC) for suspicious cervical lymph nodes (CLN) is the gold standard technique for the identification of metastases from differentiated thyroid carcinomas. Thyroglobulin protein (Tgp) assay in the washout of needles employed for FNA biopsies (FNAB) has been reported to refine and support FNAC performances, especially in cases of inadequate sampling or cystic lymph nodes. In the present work, we evaluated the usefulness of routine measurement of Tgp in the FNAB washout of suspicious cervical lymph nodes (CLN), and its ability to increase the FNAC accuracy in the diagnosis of metastatic CLN. A case study of 45 CLN with histological diagnosis from 36 patients was analyzed. Histology showed metastases from papillary thyroid carcinomas (PTC) in 31 CLN, from anaplastic thyroid cancer (ATC) in 3 CLN, from medullary thyroid cancer (MTC) in 4 CLN, and metastases from extrathyroidal malignancies in 5 CLN. Two CLN analyzed were found to be non-neoplastic. The overall accuracy of FNAC was 82.9%, and that of Tgp was 91.1%, not statistically different. However, Tgp determination was found essential in 4 cases of metastatic CLN from DTC with inadequate cytology, and in 1 case in which the FNAC provided a false negative result. We demonstrated that FNAC and Tgp assay show similar diagnostic accuracies, and that Tgp measurement may represent the only available information in case of inadequate lymph node sampling or cystic lymph nodes

    Efficacy and Safety of Neem Oil for the Topical Treatment of Bloodsucking Lice Linognathus stenopsis in Goats under Field Conditions

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    : The aim of the present study was to evaluate the efficacy and safety of neem oil on caprine pediculosis and on kids' growth performances. The neem (Azadirachta indica) belongs to the Meliaceae family, and in Eastern countries it is mainly considered for the insecticidal activities of the kernel oil. The neem seeds contain bioactive principles, such as azadirachtin A, salannin, nimbin, and nimbolide. The trial was carried out on 24 kids, 120 days old, maintained in open yards. Animals were divided in 4 homogeneous groups (n = 6 animals/group) based on age, louse count, body condition score (BCS) and live body weight: Control Group (C, saline NaCl, 0.9%), Neem Group 1 (NO-100, 100 mL of neem oil per 10 kg), Neem Group 2 (NO-200, 200 mL/10 kg), Neem Group 3 (NO-300, 300 mL/10 kg). The treatments were performed by spraying the insecticide on the goat's body. The study lasted 56 days, and weekly, the kids underwent louse count, BCS and body weight determination, and FAMACHA score. Data were analyzed by ANOVA for repeated measures. The species of lice identified was Linognathus stenopsis. Kids belonging to NO-200 and NO-300 showed a stronger reduction of louse count throughout the study (>95%). The daily weight gain recorded was significantly higher (p < 0.05) in NO-300 than C. No differences were found for BCS and FAMACHA scores. The results of this trial showed that the administration of neem oil to control caprine pediculosis caused by sucking lice represents an alternative to synthetic compounds
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