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Insights into the Analysis of Fractional Delay Differential Equations
Get PDFThis thesis is concerned with determining the analytic solution, using the method of steps, of the following fractional delay differential equation initial interval problem (FDDE IIP),
c Dαy(s) = −y(t − τ ) for t > 0, τ > 0, 0 < α < 1, and y ∈ A1(0, T ]
0 t
y(t) = ϕ(t) for t ∈ (−τ, 0]
The properties of the analytic solution obtained are a surprise but they do sit comfortably when compared with those of the analytic solutions of an ordinary differential equation initial value problem (ODE IVP), a delay differential equation
initial interval problem (DDE IIP) and an fractional ordinary differential equation initial value problem (FODE IVP). Further the analytic solution formula obtained is closely related to that of the analytic solution formula of the DDE IIP. However, these insights into the analytic solution of the FDDE IIP we have not seen before, and differ from those published elsewhere
Vélomobility is to degrowth as automobility is to growth: Prefigurative cycling imaginaries
Get PDFThis is an Accepted Manuscript of an article published by Taylor & Francis in Applied Mobilities on 16/06/2022, available online: https://doi.org/10.1080/23800127.2022.2087134At the end of the nineteenth century, the autonomous mobility provided by bicycles and tricycles created a mobile imaginary that paved the way for automobility. Through the course of the twentieth century, the growth and decline of cycling mobilities was inseparably entangled with the rise of a range of motor-mobilities (two and four wheeled). Yet cycling persists and is championed widely as a contender for future mobility in post-growth societies. However, the hegemonic position reached by automobility as a dominant system has led to closure of political non-car mobility imaginaries.
United In Science, the high-level synthesis report to the UN Climate Action Summit 2019, noted that the nationally determined contributions to carbon reduction made in the Paris agreement need to be tripled to reach target CO2 reduction levels: this will entail dramatic transformation of mobilityscapes. This paper consequently explores the possibilities and problems inherent in formulating vélomobility as a system of autonomobility, paying special attention to its alignment with the range of radical alternatives clustered around degrowth (D’Alisa, Demaria, and Kallis 2014) and the pluriverse (Kothari et al. 2019; Escobar 2020) as promising ways to think and act beyond the unsustainable carbon economy. It does so in three parts: first it examines the challenges of imagining vélomobility not just as a set of practices but cognitively, through its conceptual construction not as an inverse of automobility but as a system that also challenges the political underpinnings of automobility. Second, it considers vélomobility through a set of propositions and briefly explores through examples the complexities involved in reimagining mobility regimes as well as the resources from political theory that may be important to it. Finally, the last section reverses the gaze and asks what the reconsideration of vélomobility as described previously can bring to the broader discussion of autonomobility
Clandestine Migrant Journeys to Britain
No full textThe Aliens Act of 1905 was the culmination of decades of anxiety about migrants – some of whom attempted to reach Britain by clandestine means
Single step synthesis of WO 3 nanoparticles by wire explosion process and its photocatalytic behaviour
Get PDFFrom IOP Publishing via Jisc Publications RouterHistory: received 2020-12-21, rev-recd 2021-04-07, oa-requested 2021-04-14, accepted 2021-04-30, open-access 2021-05-11, epub 2021-05-11, ppub 2021-06-01Publication status: PublishedTungsten (W) wires are exploded in oxygen ambience to get tungsten oxide (WO3) nanoparticles (NPs). Energy stored in the capacitors (EC) is used to overcome the sublimation energy of wire. Energy ratio (K, ratio of EC and sublimation energy) and oxygen pressure (P) are two control parameters for the particle phase and morphology in the wire explosion process. X-ray diffraction (XRD) patterns confirmed the partial oxidation of W for low values of K. For K = 2, oxidation increases with increase in P. For K = 10, complete oxidation was achieved irrespective of P. Particles are spherical in shape as observed from scanning electron microscope (SEM) and transmission electron microscope (TEM) micrographs. Particle size follows a log-normal distribution with a least mean size of 24.1 nm. UV-vis diffuse reflectance spectroscopy (DRS) was used to measure the absorbance of NPs (complete WO3 with least mean size) for band gap measurement. The band gap was found to be 2.92 eV (visible region). NPs are used as photocatalyst to degrade aqueous solution of methylene blue (MB) under visible light irradiation. 500 mg l−1 of WO3 NPs were optimum to degrade 10 mg l−1 MB in 120 min
Visualising internal migration flows across local authorities in England and Wales
Get PDFFrom SAGE Publishing via Jisc Publications RouterHistory: epub 2020-11-25Publication status: PublishedInternal migration has significant impacts on the population structure, public services, economic and social development of local areas. In this research, we adopted the theory and methods of complex network analysis to visualise the internal migration flows across local authorities in England and Wales. The graphic prominently highlights two spatial and geographic characteristics of population mobility in England and Wales: a large proportion of internal migration is associated with clusters of neighbouring or nearby local authorities, and the most urban authorities, such as London and other major metropolitan cities, have net outward internal migration (i.e., more people moving out than in)
Sieve-Like CNT Film Coupled with TiO 2 Nanowire for High-Performance Continuous-Flow Photodegradation of Rhodamine B under Visible Light Irradiation
Get PDFFrom MDPI via Jisc Publications RouterHistory: accepted 2021-05-14, pub-electronic 2021-05-19Publication status: PublishedFunder: National Key Research and Development Program of China; Grant(s): 2016YFA0203301Funder: National Natural Science Foundation of China; Grant(s): 51862035, 52062048Funder: the Science and Technology Project of Jiangxi Province; Grant(s): 20192BCD40017, 20192ACB80002, S2018LQCQ0016, 2017-SJSYS-008Continuous-flow photoreactors hold great promise for the highly efficient photodegradation of pollutants due to their continuity and sustainability. However, how to enable a continuous-flow photoreactor with the combined features of high photodegradation efficiency and durability as well as broad-wavelength light absorption and large-scale processing remains a significant challenge. Herein, we demonstrate a facile and effective strategy to construct a sieve-like carbon nanotube (CNT)/TiO2 nanowire film (SCTF) with superior flexibility (180° bending), high tensile strength (75–82 MPa), good surface wettability, essential light penetration and convenient visible light absorption. Significantly, the unique architecture, featuring abundant, well-ordered and uniform mesopores with ca. 70 µm in diameter, as well as a homogenous distribution of TiO2 nanowires with an average diameter of ca. 500 nm, could act as a “waterway” for efficient solution infiltration through the SCTF, thereby, enabling the photocatalytic degradation of polluted water in a continuous-flow mode. The optimized SCTF-2.5 displayed favorable photocatalytic behavior with 96% degradation of rhodamine B (RhB) within 80 min and a rate constant of 0.0394 min−1. The continuous-flow photodegradation device made using SCTF-2.5 featured exceptional photocatalytic behavior for the continuous degradation of RhB under simulated solar irradiation with a high degradation ratio (99.6%) and long-term stability (99.2% retention after working continuously for 72 h). This work sheds light on new strategies for designing and fabricating high-performance continuous-flow photoreactors toward future uses
Validation of CIP2A as a biomarker of subsequent disease progression and treatment failure in Chronic Myeloid Leukaemia
Get PDFIt would be clinically useful to prospectively identify the risk of disease progression in chronic myeloid leukaemia (CML). Overexpression of cancerous inhibitor of protein phosphatase 2A (PP2A) (CIP2A) protein is an adverse prognostic indicator in many cancers. Methods: We examined CIP2A protein levels in diagnostic samples from the SPIRIT2 trial in 172 unselected patients, of whom 90 received imatinib and 82 dasatinib as first-line treatment. Results: High CIP2A levels correlated with inferior progression-free survival (p = 0.04) and with worse freedom from progression (p = 0.03), and these effects were confined to dasatinib recipients. High CIP2A levels were associated with a six-fold higher five-year treatment failure rate than low CIP2A levels (41% vs. 7.5%; p = 0.0002), in both imatinib (45% vs. 11%; p = 0.02) and dasatinib recipients (36% vs. 4%; p = 0.007). Imatinib recipients with low CIP2A levels had a greater risk of treatment failure (p = 0.0008). CIP2A levels were independent of Sokal, Hasford, EUTOS (EUropean Treatment and Outcome Study), or EUTOS long-term survival scores (ELTS) or the presence of major route cytogenetic abnormalities. No association was seen between CIP2A levels and time to molecular response or the levels of the CIP2A-related proteins PP2A, SET, SET binding protein 1 (SETBP1), or AKT. Conclusions: These data confirm that high diagnostic CIP2A levels correlate with subsequent disease progression and treatment failure. CIP2A is a simple diagnostic biomarker that may be useful in planning treatment strategies
Publisher Correction: Control of electron–electron interaction in graphene by proximity screening
Get PDFFrom Springer Nature via Jisc Publications RouterHistory: registration 2020-05-21, pub-electronic 2020-06-11, online 2020-06-11, collection 2020-12Publication status: PublishedAn amendment to this paper has been published and can be accessed via a link at the top of the paper
Towards a Bio-Inspired Real-Time Neuromorphic Cerebellum
Get PDFFrom Frontiers via Jisc Publications RouterHistory: received 2020-10-29, collection 2021, accepted 2021-03-24, epub 2021-05-31Publication status: PublishedThis work presents the first simulation of a large-scale, bio-physically constrained cerebellum model performed on neuromorphic hardware. A model containing 97,000 neurons and 4.2 million synapses is simulated on the SpiNNaker neuromorphic system. Results are validated against a baseline simulation of the same model executed with NEST, a popular spiking neural network simulator using generic computational resources and double precision floating point arithmetic. Individual cell and network-level spiking activity is validated in terms of average spike rates, relative lead or lag of spike times, and membrane potential dynamics of individual neurons, and SpiNNaker is shown to produce results in agreement with NEST. Once validated, the model is used to investigate how to accelerate the simulation speed of the network on the SpiNNaker system, with the future goal of creating a real-time neuromorphic cerebellum. Through detailed communication profiling, peak network activity is identified as one of the main challenges for simulation speed-up. Propagation of spiking activity through the network is measured, and will inform the future development of accelerated execution strategies for cerebellum models on neuromorphic hardware. The large ratio of granule cells to other cell types in the model results in high levels of activity converging onto few cells, with those cells having relatively larger time costs associated with the processing of communication. Organizing cells on SpiNNaker in accordance with their spatial position is shown to reduce the peak communication load by 41%. It is hoped that these insights, together with alternative parallelization strategies, will pave the way for real-time execution of large-scale, bio-physically constrained cerebellum models on SpiNNaker. This in turn will enable exploration of cerebellum-inspired controllers for neurorobotic applications, and execution of extended duration simulations over timescales that would currently be prohibitive using conventional computational platforms
Ultra-Structural Imaging Provides 3D Organization of 46 Chromosomes of a Human Lymphocyte Prophase Nucleus
Get PDFFrom MDPI via Jisc Publications RouterHistory: accepted 2021-05-23, pub-electronic 2021-06-01Publication status: PublishedFunder: Biotechnology and Biological Sciences Research Council; Grant(s): BB/H022597/1Three dimensional (3D) ultra-structural imaging is an important tool for unraveling the organizational structure of individual chromosomes at various stages of the cell cycle. Performing hitherto uninvestigated ultra-structural analysis of the human genome at prophase, we used serial block-face scanning electron microscopy (SBFSEM) to understand chromosomal architectural organization within 3D nuclear space. Acquired images allowed us to segment, reconstruct, and extract quantitative 3D structural information about the prophase nucleus and the preserved, intact individual chromosomes within it. Our data demonstrate that each chromosome can be identified with its homolog and classified into respective cytogenetic groups. Thereby, we present the first 3D karyotype built from the compact axial structure seen on the core of all prophase chromosomes. The chromosomes display parallel-aligned sister chromatids with familiar chromosome morphologies with no crossovers. Furthermore, the spatial positions of all 46 chromosomes revealed a pattern showing a gene density-based correlation and a neighborhood map of individual chromosomes based on their relative spatial positioning. A comprehensive picture of 3D chromosomal organization at the nanometer level in a single human lymphocyte cell is presented
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