652 research outputs found

    A typological assessment of Iron Age weapons in South Italy

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    Typologies, especially of spearheads, have been decried as inadequate by the archaeological community. They have prevented the synthetic study of ancient weapons and obscured cultural contacts, changes in form and distribution, and changes in fighting style. This thesis presents new typologies of spearheads and swords which are not based on aesthetics or the need to communicate a large amount of material succinctly in the limited space of a site report. Rather, these typologies attempt to perceive the functional characteristics of these weapon classes. The thesis surveys a range of sites in Daunia, Basilicata and Southern Campania applying these new typologies to large suites of weapons. From this assessment a number of conclusions have flowed regarding cultural contacts between indigenous Southern Italic groups and with immigrating groups of Villanovan and Greek origin. The assessment reveals the variety of weapon forms in use and tracks changes over time. These changes expose cultural transformations and alterations in fighting styles. The tracking of paraphernalia often associated with weapons in modern scholarship has also revealed some nuances in patterns of association with weapons which were not previously apparent

    SOME RESULTS ON SEMI-REFLEXIVITY AND REFLEXIVITY IN LOCALLY CONVEX SPACES

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    In this paper we discuss that if E[] is a barreled space such that every bounded subset of E is relatively compact, then E[] is reflexive, and that a barreled space E[Ï„] in which there is a denumerable system of convex compact subsets is reflexive. We also discuss Some hereditary-type properties of reflexive locally convex spaces. Keywords: Bornological space, barreled, hereditarily-reflexive, M-space, quasi-complete, reflexive, strong dual. AMS (2010) Mathematics Subject Classification: 46A25

    Ge/SiGe Quantum Well p-i-n Structures for Uncooled Infrared Bolometers

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    Cataloged from PDF version of article.The temperature dependence of current is investigated experimentally for silicon–germanium (Si-Ge) multi-quantum-well p-i-n devices on Si substrates as uncooled bolometer active layers. Temperature coefficient of resistance values as high as −5.8%/K are recorded. This value is considerably higher than that of even commercial bolometer materials in addition to being well above the previous efforts based on CMOS compatible materials

    Electrochemical cardiac troponin I immunosensor based on nitrogen and boron-doped graphene quantum dots electrode platform and Ce-doped SnO2/SnS2 signal amplification

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    The detection of acute myocardial infarction directly depends on the concentration of the cardiac troponin I (CTnI) in human blood plasma. In this study, the sensitive, selective, and fast sandwich-type electrochemical CTnI immunosensor was developed by using nitrogen and boron-dopped graphene quantum dots -as electrode platform and two-dimensional Ce-dopped SnO2/SnS2 (Ce–SnO2/SnS2) as signal amplification. In preparation of electrochemical CTnI immunosensor, the coordinated covalent bond between capture antibody (anti-CTnI-Ab1) and nitrogen and boron-dopped graphene quantum dots as electrode platform led to immobilization of anti-CTnI-Ab1, and the strong esterification between the secondary antibody (anti-CTnI-Ab2) and thioglycolic acid-modified Ce–SnO2/SnS2 resulted in anti-CTnI-Ab2 conjugation. Finally, the resultant electrochemical CTnI immunosensor was formed via antigen-antibody interaction. High-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, UV–Vis spectroscopy and Raman spectroscopy, as well as some electrochemical characterization techniques, including cyclic voltammetry, differential pulse voltammetry and electrochemical impedance spectroscopy were used to characterize the prepared immunosensor. The detection limit of CTnI in plasma samples was calculated as 2.00 fg mL−1, making it an effective tool for acute myocardial infarction testing. © 2021 Elsevier Lt

    Direct Reactions with Light Neutron-Rich Nuclei

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    Probing the Z = 6 spin-orbit shell gap with (p,2p) quasi-free scattering reactions

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    The evolution of the traditional nuclear magic numbers away from the valley of stability is an active field of research. Experimental efforts focus on providing key spectroscopic information that will shed light into the structure of exotic nuclei and understanding the driving mechanism behind the shell evolution. In this work, we investigate the Z=6 spin-orbit shell gap towards the neutron dripline. To do so, we employed NA(p,2p)CA−1 quasi-free scattering reactions to measure the proton component of the 21+ state of 16,18,20C. The experimental findings support the notion of a moderate reduction of the proton 1p1/2−1p3/2 spin-orbit splitting, at variance to recent claims for a prevalent Z=6 magic number towards the neutron dripline.</p

    Dynamic tuning of plasmon resonance in the visible using graphene

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    We report active electrical tuning of plasmon resonance of silver nanoprisms (Ag NPs) in the visible spectrum. Ag NPs are placed in close proximity to graphene which leads to additional tunable loss for the plasmon resonance. The ionic gating of graphene modifies its Fermi level from 0.2 to 1 eV, which then affects the absorption of graphene due to Pauli blocking. Plasmon resonance frequency and linewidth of Ag NPs can be reversibly shifted by 20 and 35 meV, respectively. The coupled graphene-Ag NPs system can be classically described by a damped harmonic oscillator model. Atomic layer deposition allows for controlling the graphene-Ag NP separation with atomic-level precision to optimize coupling between them. © 2016 Optical Society of America

    Wholegrain fermentation affects gut microbiota composition, phenolic acid metabolism and pancreatic beta cell function in a rodent model of type 2 diabetes

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    The intestinal microbiota plays an important role in host metabolism via production of dietary metabolites. Microbiota imbalances are linked to type 2 diabetes (T2D), but dietary modification of the microbiota may promote glycemic control. Using a rodent model of T2D and an in vitro gut model system, this study investigated whether differences in gut microbiota between control mice and mice fed a high-fat, high-fructose (HFHFr) diet influenced the production of phenolic acid metabolites following fermentation of wholegrain (WW) and control wheat (CW). In addition, the study assessed whether changes in metabolite profiles affected pancreatic beta cell function. Fecal samples from control or HFHFr-fed mice were fermented in vitro with 0.1% (w/v) WW or CW for 0, 6, and 24 h. Microbiota composition was determined by bacterial 16S rRNA sequencing and phenolic acid (PA) profiles by UPLC-MS/MS. Cell viability, apoptosis and insulin release from pancreatic MIN6 beta cells and primary mouse islets were assessed in response to fermentation supernatants and selected PAs. HFHFr mice exhibited an overall dysbiotic microbiota with an increase in abundance of proteobacterial taxa (particularly Oxalobacteraceae) and Lachnospiraceae, and a decrease in Lactobacillus. A trend toward restoration of diversity and compositional reorganization was observed following WW fermentation at 6 h, although after 24 h, the HFHFr microbiota was monodominated by Cupriavidus. In parallel, the PA profile was significantly altered in the HFHFr group compared to controls with decreased levels of 3-OH-benzoic acid, 4-OH-benzoic acid, isoferulic acid and ferulic acid at 6 h of WW fermentation. In pancreatic beta cells, exposure to pre-fermentation supernatants led to inhibition of insulin release, which was reversed over fermentation time. We conclude that HFHFr mice as a model of T2D are characterized by a dysbiotic microbiota, which is modulated by the in vitro fermentation of WW. The differences in microbiota composition have implications for PA profile dynamics and for the secretory capacity of pancreatic beta cells

    Observability and nonlinear filtering

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    This paper develops a connection between the asymptotic stability of nonlinear filters and a notion of observability. We consider a general class of hidden Markov models in continuous time with compact signal state space, and call such a model observable if no two initial measures of the signal process give rise to the same law of the observation process. We demonstrate that observability implies stability of the filter, i.e., the filtered estimates become insensitive to the initial measure at large times. For the special case where the signal is a finite-state Markov process and the observations are of the white noise type, a complete (necessary and sufficient) characterization of filter stability is obtained in terms of a slightly weaker detectability condition. In addition to observability, the role of controllability in filter stability is explored. Finally, the results are partially extended to non-compact signal state spaces
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