4,727 research outputs found
Wavelength tunable 10-GHz 3-ps pulse source using a dispersion decreasing fiber-based nonlinear optical loop mirror
We experimentally demonstrate the use of a dispersion decreasing fiber (DDF)-based nonlinear optical loop mirror (NOLM) for the generation of wavelength tunable soliton-like pulses at a repetition rate of 10 GHz. We compress ~12 ps Gaussian pulses from an electro-absorption modulator (EAM) (followed by 125 m of DCF for preliminary linear dispersion compensation) into 3 ps pedestal-free pulses using both high-order soliton compression and nonlinear switching effects within an 8.5 km DDF-based loop mirror. The output pulses from the DDF-based NOLM show considerable pedestal reduction compared to those obtained by directly compressing the EAM seed pulses via a single passage through the DDF. Wavelength tuning of the compressed pulses over a ~15 nm bandwidth (from 1541 to 1556 nm) is demonstrated without a significant increase in pulse duration or degradation in pulse quality
Player agency in interactive narrative: audience, actor & author
The question motivating this review paper is, how can
computer-based interactive narrative be used as a constructivist learn-
ing activity? The paper proposes that player agency can be used to
link interactive narrative to learner agency in constructivist theory,
and to classify approaches to interactive narrative. The traditional
question driving research in interactive narrative is, ‘how can an in-
teractive narrative deal with a high degree of player agency, while
maintaining a coherent and well-formed narrative?’ This question
derives from an Aristotelian approach to interactive narrative that,
as the question shows, is inherently antagonistic to player agency.
Within this approach, player agency must be restricted and manip-
ulated to maintain the narrative. Two alternative approaches based
on Brecht’s Epic Theatre and Boal’s Theatre of the Oppressed are
reviewed. If a Boalian approach to interactive narrative is taken the
conflict between narrative and player agency dissolves. The question
that emerges from this approach is quite different from the traditional
question above, and presents a more useful approach to applying in-
teractive narrative as a constructivist learning activity
Molecular dynamics simulations to investigate the relationship between the structural stability and amyloidogenesis of the wild-type and N-terminal hexapeptide deletion Delta N6 beta 2-microglobulin
Effect of Additive PS and PPO in PS-b-P2VP on Trapping of Structural Coloration
Photonic crystals prepared from self-assembled diblock copolymers (BCPs) have many advantages, such as flexibility, light weight, and facile fabrication process. Many applications in optical delivery systems are proposed, such as thermal sensing and anti-counterfeiting labels. In this study, polystyrene-block-poly(2-vinylpyridine) (PS-P2VP) was employed to examine the controlling factors of trapping of structural coloration (TOSC). The ability to capture structural color in blend films was investigated by blending homopolymer PS with different molecular weights. The entanglement density, craze stress, craze strain and osmotic pressure are also discussed. By blending PPO to PS-P2VP with different PS/PPO weight ratios, the change of mechanical properties (Young's modulus) can significantly affect the optical property of the films. Moreover, heat resistance of the TOSC-featured film is enhanced with the increase of the PPO content. To provide a comprehensive understanding of the intricate phenomena involved, in-situ spectroscopic measurements were carried out. These measurements were instrumental in comprehending the response of PS-P2VP systems with varying molecular compositions to the swelling behavior induced by ethanol. Consequently, the intricate interplay of factors influencing the formation of the crazed microlayer of TOSC is investigated, enabling the creation of photonic crystal materials with tailor-made optical and thermal properties for potential applications in fields such as thermal sensing and anti-counterfeiting labels within optical delivery systems
Charisma and Spirituality in the Early Church: A Study of Messalianism and Pseudo-Macarius
The thesis is an investigation into the concept of Charisma and Spirituality in the Early Church with particular emphasis upon the writings of Ps-Macarius, and of a group of ascetics known as the Messalians, evident in the late fourth / early fifth centuries. The Macarian writings are
examined to see what they reveal about the experiential pneumatic theology of the Early Church, the relationship between Syrian and Hellenic traditions of Christian Rhetoric, and the relationship between Ps-Macarius and the Cappadocian Circle. The Macarian corpus as a whole is examined to assess its rhetorical influences and style. The rhetoric of the Macarian corpus is seen to illustrate a high degree of sophistication. This study also gives definition to two terms that have become imprecise and diverse in their use: 'enkrateia' (self-control), and
`Syrian Christianity'. By isolating the characteristics of enkratefa the definitive stages of an encratic lifestyle are identified. The breaking down of the term into enkrateia, radical enkrateta and exclusive enkrateta enables a much clearer discussion to take place as to the
nature of the encratic theology of a group or individual. The final element of this study is a consideration of the distinct Macarian imagery that is evident within the corpus. Two images are considered in detail, the 'flight of the soul' and 'sober intoxication'. Overall this study
shows the variety of influences upon Ps-Macarius, and the uniqueness of his expression. The influences upon Ps-Macarius include a context of endemic Syrian spirituality, a radical encratic lifestyle, a Hellenic rhetorical training, and a distinct interpretation of Platonic and Neo-
Platonic images, coupled to the wider Judaic / Mesopotamian influences of his Church. It is shown that Ps-Macarius represents an individual voice that is distinct and recognisable amongst the Fathers of the Church
Nuclear translocation and signalling of L1-CAM in human carcinoma cells requires ADAM10 and presenilin/gamma-secretase activity
L1-CAM (L1 cell-adhesion molecule), or more simply L1, plays an important role in the progression of human carcinoma. Overexpression promotes tumour-cell invasion and motility, growth in nude mice and tumour metastasis. It is feasible that L1-dependent signalling contributes to these effects. However, little is known about its mechanism in tumour cells. We reported previously that L1 is cleaved by ADAM (a disintegrin and metalloprotease) and that the cytoplasmic part is essential for L1 function. Here we analysed more closely the role of proteolytic cleavage in L1-mediated nuclear signalling. Using OVMz carcinoma cells and L1-transfected cells as a model, we found that ADAM10-mediated cleavage of L1 proceeds in lipid raft and non-raft domains. The cleavage product, L1-32, is further processed by PS (presenilin)/gamma-secretase to release L1-ICD, an L1 intracellular domain of 28 kDa. Overexpression of dominantnegative PS1 or use of a specific gamma-secretase inhibitor leads to an accumulation of L1-32. Fluorescence and biochemical analysis revealed a nuclear localization for L1-ICD. Moreover, inhibition of ADAM10 and/or gamma-secretase blocks nuclear translocation of L1-ICD and L1-dependent gene regulation. Overexpression of recombinant L1-ICD mediates gene regulation in a similar manner to full-length L1. Our results establish for the first time that regulated proteolytic processing by ADAM10 and PS/gamma-secretase is essential for the nuclear signalling of L1 in human carcinoma cell lines. Key words: a disintegrin and metalloprotease 10 (ADAM10), L1 cell-adhesion molecule (L1-CAM), nuclear translocation, presenilin (PS)/gamma-secretase activity, raft, signalling
Lindane, a gap junction blocker, suppresses FSH and transforming growth factor β1-induced connexin43 gap junction formation and steroidogenesis in rat granulosa cells.
Design, synthesis and biological evaluation of heterocycle-conjugated styrene derivatives as protein tyrosine kinase inhibitors and free radical scavengers.
LinoSPAD2: A 512×1 linear SPAD camera with system-level 135-ps SPTR and a reconfigurable computational engine for time-resolved single-photon imaging
The LinoSPAD2 camera combines a 512×1 linear single-photon avalanche diode (SPAD) array with an FPGA-based photon-counting and time-stamping platform, to create a reconfigurable sensing system capable of detecting single photons. The read-out is fully parallel, where each SPAD is connected to a different FPGA input. The hardware can be reconfigured to achieve different functionalities, such as photon counters, time-to-digital converter (TDC) arrays and histogramming units. Time stamping is performed by an array of 64 TDCs, with 20 ps resolution (LSB), serving 256 channels by means of 4:1 sharing. At sensor level, the pixel pitch is 26.2 μm with a fill factor of 25.1%. The median dark count rate of each SPAD at room temperature is below 100 cps at 6V excess bias, the single-photon timing resolution (SPTR) of each channel is 50 ps FWHM, and the peak photon detection probability reaches ~50% at 510 nm at the same excess bias. The fill factor can be increased by 2.3× by means of microlenses, with good spatial uniformity and flat spectral response above 400 nm. At system level, the average instrument response function (IRF) is 135 ps FWHM. The LinoSPAD2 camera enables a wide range of time-of-flight and time-resolved applications, including 3D imaging, fluorescence lifetime imaging microscopy (FLIM), heralded spectroscopy, and compressive Raman imaging, to name a few. Thanks to its features, LinoSPAD2 is a novel generation of reconfigurable single-photon image sensors capable of adapting their read-out and processing to match application-specific requirements, and combining SPAD arrays with advanced, massively-parallel computational functionalities. Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.QCD/DiCarlo La
Synthesis and Characterization of PEO-PS-PEO Triblock Copolymer Conjugated with Ni-NTA for Biosensors, 2018
Poly(ethylene oxide)-poly(styrene)-poly(ethylene oxide) triblock copolymer with di-hydroxyl terminated groups (HO-PEO-PS-PEO-OH) was conjugated with nitrilotriacetic acid (NTA) via esterification reaction using N,N'-Dicyclohexylcarbodiimide (DCC), 4-Dimethylaminopyridine (DMAP) and Dimethylformamide (DMF) as a solvent at 80 ?C. The poly(ethylene oxide)-poly(styrene)-poly(ethylene oxide) with NTA end groups (NTA-PEO-PS-PEO-NTA) was characterized and structure confirmed by 1H NMR, 13C NMR, and FT-IR spectroscopies. Thermogravimetric analysis (TGA) was carried out to investigate the thermal stability of the starting triblock copolymer poly(ethylene oxide)-poly(styrene)-poly(ethylene oxide) with di-hydroxyl terminated groups (HO-PEO-PS-PEO-OH) and the conjugated poly(ethylene oxide)-poly(styrene)-poly(ethylene oxide) functional polymer (NTA-PEO-PS-PEO-NTA). Surface morphologies of the (HO-PEO-PS-PEO-OH) and (NTA-PEO-PS-PEO-NTA) were studied by atomic force microscopy. In addition, the size distributions were determined using dynamic light scattering. The thermal behavior of the (HO-PEO-PS-PEO-OH) and (NTA-PEO-PS-PEO-NTA) were examined by differential scanning calorimetry (DSC). DSC thermograms indicate the formation of a two phase polymer matrix. The poly(ethylene oxide)-poly(styrene)-poly(ethylene oxide) with NTA functionalized end groups (NTA-PEO-PS-PEO-NTA) was bound or chelated with Ni(II) metal ion. The binding studies were carried out by ultraviolet-visible (UV-Vis) spectroscopy. The electronic behaviors of PEO-b-PS-b-PEO/ PS/ NTA-PEO-b-PS-b-PEO-NTA with ratio (1/5/1) and PEO-b-PS-b-PEO/ PS/ NTA-PEO-b-PS-b-PEO-NTA-Ni containing 1% of oxidized single-walled carbon nanotubes (SWCNTs) were investigated by IV plots from Kelvin sensing. The IV plots before sensitizing with protein varied from the IV plots after binding with protein indicating that the composites may be used as active components in biosensors. KEYWORDS: Materials Chemistry, Polymer Chemistr
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