cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Delocalization of topological edge states
Creators: name: Zhu, Weiwei
name: Teo, Wei Xin
name: Li, Linhu
name: Gong, Jiangbin
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The non-Hermitian skin effect (NHSE) in non-Hermitian lattice systems depicts the exponential localization of eigenstates at system's boundaries. It has led to a number of counter-intuitive phenomena and challenged our understanding of bulk-boundary correspondence in topological systems. This work aims to investigate how the NHSE localization and topological localization of in-gap edge states compete with each other, with several representative static and periodically driven 1D models, whose topological properties are protected by different symmetries. The emerging insight is that at critical system parameters, even topologically protected edge states can be perfectly delocalized. In particular, it is discovered that this intriguing delocalization occurs if the real spectrum of the system's edge states falls on the same system's complex spectral loop obtained under the periodic boundary condition. We have also performed sample numerical simulation to show that such delocalized topological edge states can be safely reconstructed from time-evolving states. Possible applications of delocalized topological edge states are also briefly discussed.
description: 9 pages, 8 figures, comments are welcome
Application of Gallium Nitride Transistors in Power Electronics for PV Systems
Creators: name: Hensel, A.
name: Faulhaber, F.
name: Kranzer, D.
Publisher: name: WIP
Year: 2012
Subjects: Components for PV Systems
Balance of System Components

description: 27th European Photovoltaic Solar Energy Conference and Exhibition; 3098-3102
description: The benefits of the application of gallium nitride (GaN) based transistors in power electronics for photovoltaic (PV) systems are demonstrated in this paper. Newly available transistors with blocking voltages from 40 V to 600 V, low on state resistance and very good switching performance are well suited for this application where cost, efficiency and power density are highly important. Different GaN transistors are presented and their key
attributes are analysed. Three examples for the application of the transistors (boost converter for PV systems, module integrated power optimizer, single phase PV inverter) are demonstrated and related measurement results are shown to prove the suitability of the transistors for these applications.
The role of cyclic AMP and differentiation-inducing factor in stalk cell differentiation during the development of the cellular slime mold Dictyostelium discoideum
Creators: name: Sobolewski, Andre
Publisher: name: University of British Columbia
Year: 2010

description: The role of cyclic AMP and a differentiation-indueing factor (DIF) in the differentiation of stalk cells was investigated in the cellular slime mold Dictyostelium discoideum. In this organism, starvation triggers the aggregation of amoebae into multicellular masses within which a simple, well-regulated pattern of partially differentiated cells is formed and which ultimately form fruiting bodies comprised of spore and stalk cells. In a monolayer system at low cell densities, stalk cell formation is dependent on the presence of both cyclic AMP and DIF. Both factors act within a short time of each other, induction by cyclic AMP preceding induction by DIF, beginning between 8 to 10 hours of incubation in monolayers, and progressively committing an increasing proportion of the cells in monolayer to form stalk cells. The relative effectiveness of analogues of cyclic AMP to induce stalk cell formation in monolayers indicates that the well-characterized cell surface cyclic AMP receptor most probably mediates the action of cyclic AMP. Although this receptor appears early during aggregation, it does not become activated until later during development in vivo, probably because the cyclic AMP concentrations within developing cell masses must build up to levels higher than those in aggregation streams. The finding that caffeine inhibits stalk cell formation in low density monolayers and that the permeable analogue 8-Bromo-cyclic AMP can partially reverse this inhibition suggests that activation of this receptor leads to an increase in internal cyclic AMP levels as one of the steps in stalk cell differentiation. The finding that the expression in low density monolayers of AP IV, a cell-type non-specific isozyme of acid phosphatase, was cyclic AMP-dependent is consistent with the view that cyclic AMP induces non-specific postaggregative gene expression during development in vivo. The findings that the expression of pre-stalk arid stalk cell specific antigens and of the pre-stalk cell specific isozyme AP II was DIF-dependent provide good evidence for the idea that both pre-stalk and stalk cell formation are induced by DIF. The fact that isolated pre-stalk cells require DIF for stalk cell formation in low density monolayers further supports this idea. Whereas cells independent of DIF for stalk cell formation in monolayers appear immediately after cyclic AMP-independent cells during differentiation in low density monolayers, DIF-independent cells appear considerably later during development in vivo. This evidence and the fact that developing cell masses contain elevated levels of DIF lead to the postulate that the factor(s) which triggers the formation of fruiting bodies also controls the pre-stalk to stalk cell conversion.
Pancreas deficiency modifies bone development in the ovine fetus near term.
Creators: name: Lanham, Stuart A
name: Blache, Dominique
name: Oreffo, Richard OC
name: Fowden, Abigail L
name: Forhead, Alison
Publisher: name: Apollo - University of Cambridge Repository
Year: 2021

description: Hormones have an important role in the regulation of fetal growth and development, especially in response to nutrient availability in utero. Using micro-CT and an electromagnetic three-point bend test, this study examined the effect of pancreas removal at 0.8 fraction of gestation on the developing bone structure and mechanical strength in fetal sheep. When fetuses were studied at 10 and 25 days after surgery, pancreatectomy caused hypoinsulinaemia, hyperglycaemia and growth retardation which was associated with low plasma concentrations of leptin and a marker of osteoclast activity and collagen degradation. In pancreatectomized fetuses compared to control fetuses, limb lengths were shorter, and trabecular (Tb) bone in the metatarsi showed greater bone volume fraction, Tb thickness, degree of anisotropy and porosity, and lower fractional bone surface area and Tb spacing. Mechanical strength testing showed that pancreas deficiency was associated with increased stiffness and a greater maximal weight load at fracture in a subset of fetuses studied near term. Overall, pancreas deficiency in utero slowed the growth of the fetal skeleton and adapted the developing bone to generate a more compact and connected structure. Maintenance of bone strength in growth-retarded limbs is especially important in a precocial species in preparation for skeletal loading and locomotion at birth.
Additional file 1 of Radiofrequency ablation versus repeat hepatectomy in the treatment of recurrent hepatocellular carcinoma in subcapsular location: a retrospective cohort study
Creators: name: Wei, Fuqun
name: Huang, Qizhen
name: Zhou, Yang
name: Luo, Liuping
name: Zeng, Yongyi
Publisher: name: figshare
Year: 2021
Subjects: subject: Medicine
subject: Microbiology
subject: FOS: Biological sciences
subject: Biotechnology
subject: Chemical Sciences not elsewhere classified
subject: Ecology
subject: Immunology
subject: FOS: Clinical medicine
subject: Cancer
subject: Infectious Diseases
subject: FOS: Health sciences

description: Additional file 1: Supplementary Table 1. Baseline characteristics before and after propensity score matching.
Extreme suction attachment performance from specialised insects living in mountain streams (Diptera: Blephariceridae).
Creators: name: Kang, Victor
name: White, Robin T
name: Chen, Simon
name: Federle, Walter
Publisher: name: Apollo - University of Cambridge Repository
Year: 2021
Subjects: subject: Research Article
subject: Ecology
subject: FOS: Biological sciences
subject: Physics of Living Systems
subject: biomechanics
subject: adhesion
subject: underwater adhesion
subject: aquatic invertebrate
subject: surface roughness
subject: Other

description: Suction is widely used by animals for strong controllable underwater adhesion but is less well understood than adhesion of terrestrial climbing animals. Here we investigate the attachment of aquatic insect larvae (Blephariceridae), which cling to rocks in torrential streams using the only known muscle-actuated suction organs in insects. We measured their attachment forces on well-defined rough substrates and found that their adhesion was less reduced by micro-roughness than that of terrestrial climbing insects. In vivo visualisation of the suction organs in contact with microstructured substrates revealed that they can mould around large asperities to form a seal. We have shown that the ventral surface of the suction disc is covered by dense arrays of microtrichia, which are stiff spine-like cuticular structures that only make tip contact. Our results demonstrate the impressive performance and versatility of blepharicerid suction organs and highlight their potential as a study system to explore biological suction mechanisms.
A Concentrator Photovoltaic Panel Prototype: Realization and Characterization
Creators: name: Musio, M.
name: Pisanu, T.
name: Damiano, A.
Publisher: name: WIP
Year: 2012
Subjects: Material Studies, New Concepts and Ultra-High Efficiency
Terrestrial Concentrator Systems

description: 27th European Photovoltaic Solar Energy Conference and Exhibition; 218-223
description: In this paper the prototype of concentrator photovoltaic (CPV) panel with Fresnel lenses primary
optical elements has been characterized. The module has been developed by the National Institute for Astrophysics
(INAF) of Cagliari. The testing and characterization process has been developed at the Sardegna Ricerche PV
Laboratory. The optical and mechanical design of the proposed CPV module is firstly reported. Afterwards the
outdoor testing results are presented. Most of panel components have been characterized in order to understand the
weight of each element on the energy conversion process and on energy efficiency. In particular, the performances of
primary and secondary optical elements, photovoltaic multi-junction cell and solar receiver heat sink have been
assessed. A special attention has been paid to the evaluation of the module angle acceptance and to the analysis of the
spatial distribution of the concentrated solar radiation on the cell plane in order to understand the influence of tracker
accuracy and irradiance non-uniformity on the CPV prototype electrical performances. The characterization activity
has been completed with an accurate analysis of the meteorological conditions measurements at the Sardegna
Ricerche outdoor Photovoltaic Laboratory test bench, in order to verify the suitability of the site to the IEC 62670
standard draft.
Collective Modes in Two-band Superconductors
Creators: name: Anishchanka, A.
name: Volkov, A. F.
name: Efetov, K. B.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We analyze collective modes in two-band superconductors in the dirty limit. It is shown that these modes exist at all temperatures $T$ below $T_{c}$ provided the frequency of the modes is higher than the inelastic scattering rate and lower than the energy gaps $Δ_{a,b}$. At low temperatures these modes are related to counterphase oscillations of the condensate currents in each band. The spectrum of the collective oscillations is similar to the spectrum of the Josephson ''plasma'' modes in a tunnel Josephson junction but the velocity of the mode propagation in the case under consideration is much lower. At higher temperatures ($Δ_{b}
description: 13 pages, 5 figures; replotted figures and added references, submitted to Phys. Rev. B
A Proper Alternative: Ultra Sonic Bonding for Thin Film Solar Cell Interconnections
Creators: name: Klengel, R.
name: Stephan, T.
name: Petzold, M.
name: Schindler, S.
name: Schneider, J.
name: Spira, K.
Publisher: name: WIP
Year: 2012
Subjects: Thin Film Solar Cells
CdTe, CIS and Related Ternary and Quaternary Thin Film Solar Cells

description: 27th European Photovoltaic Solar Energy Conference and Exhibition; 2864-2867
description: Many different concepts of cell interconnections were aspired during the last years. Within our work, we
evaluated an ultrasonic bonding process to interconnect CIGS thin film modules. There are several advantages to shift to
an ultrasonic bonding process as thin film back-end interconnection: less material costs (no silver), lead and flux free,
simple automation grade and high process control. Furthermore the bonding process is free of wetting or adhesion
problems, compared to solder joint formation or conductive adhesive handling.
Micro structure analyzes of the connection interface were performed using scanning electron microscopy (SEM),
transmission electron microscopy (TEM) and scanning acoustic microscopy (SAM). Furthermore the characterization of
specific contact resistance was evaluated with the transmission line model (TLM) method.
Geodesic of the Quotient-Affine Metrics on Full-Rank Correlation Matrices
Creators: name: Thanwerdas, Yann
name: Pennec, Xavier
Publisher: name: arXiv
Year: 2021
Subjects: subject: Differential Geometry (math.DG)
subject: FOS: Mathematics

description: Correlation matrices are used in many domains of neurosciences such as fMRI, EEG, MEG. However, statistical analyses often rely on embeddings into a Euclidean space or into Symmetric Positive Definite matrices which do not provide intrinsic tools. The quotient-affine metric was recently introduced as the quotient of the affine-invariant metric on SPD matrices by the action of diagonal matrices. In this work, we provide most of the fundamental Riemannian operations of the quotient-affine metric: the expression of the metric itself, the geodesics with initial tangent vector, the Levi-Civita connection and the curvature.
Forest defoliator outbreaks alter nutrient cycling in northern waters.
Creators: name: Woodman, Samuel
name: Khoury, Sacha
name: Fournier, Ronald E
name: Emilson, Erik JS
name: Gunn, John M
name: Rusak, James A
name: Tanentzap, Andrew
Publisher: name: Apollo - University of Cambridge Repository
Year: 2021
Subjects: Article
/631/158/2459
/704/158/2445
/631/158/47/4112
/631/158/2449
/631/158/2454
article

description: Insect defoliators alter biogeochemical cycles from land into receiving waters by consuming terrestrial biomass and releasing biolabile frass. Here, we related insect outbreaks to water chemistry across 12 boreal lake catchments over 32-years. We report, on average, 27% lower dissolved organic carbon (DOC) and 112% higher dissolved inorganic nitrogen (DIN) concentrations in lake waters when defoliators covered entire catchments and reduced leaf area. DOC reductions reached 32% when deciduous stands dominated. Within-year changes in DOC from insect outbreaks exceeded 86% of between-year trends across a larger dataset of 266 boreal and north temperate lakes from 1990 to 2016. Similarly, within-year increases in DIN from insect outbreaks exceeded local, between-year changes in DIN by 12-times, on average. As insect defoliator outbreaks occur at least every 5 years across a wider 439,661 km2 boreal ecozone of Ontario, we suggest they are an underappreciated driver of biogeochemical cycles in forest catchments of this region.
description: Natural Environment Research Council (NE/L006561/1) Ontario Centres of Excellence (OCE/27649) Natural Sciences and Engineering Research Council of Canada (NSERC/509182-17)
Nucleosynthesis from massive stars 50 years after B2FH
Creators: name: Meynet, Georges
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We review some important observed properties of massive stars. Then we discuss how mass loss and rotation affect their evolution and help in giving better fits to observational constraints. Consequences for nucleosynthesis at different metallicities are discussed. Mass loss appear to be the key feature at high metallicity, while rotation is likely dominant at low and very low metallicities. We discuss various indications supporting the view that very metal poor stars had their evolution strongly affected by rotational mixing. Many features, like the origin of primary nitrogen at low metallicity, that of the C-rich extremely metal poor halo stars, of He-rich stars in massive globular clusters, of the O-Na anticorrelation in globular clusters may be related to the existence of a population of very fast rotating metal poor stars that we tentatively call the {\it spinstars}. A fraction of these {\it spinstars} may also be the progenitors of GRB in very metal poor regions. They may avoid pair instability explosion due to the heavy mass loss undergone during their early evolutionary phases and be, dependent on their frequency, important sources of ionising photons in the early Universe.
description: 46 pages, 17 figures, in Stellar Nucleosynthesis: 50 years after B2FH, C. Charbonnel and J.P. Zahn (Eds.), EAS publications Series
Potential Induced Degradation in Mono-Crystalline Silicon Based Modules: An Acceleration Model
Creators: name: Hattendorf, J.
name: Löw, R.
name: Gnehr, W.-M.
name: Wulff, L.
name: Koekten, M.C.
name: Koshnicharov, D.
name: Blauaermel, A.
name: Esquivel, J.A.
Publisher: name: WIP
Year: 2012
Subjects: Components for PV Systems
PV Modules

description: 27th European Photovoltaic Solar Energy Conference and Exhibition; 3405-3410
description: As a possible root cause of significant power loss in large-scale photovoltaic systems, the potential
induced degradation (PID) is subjected to intense investigations among the photovoltaic community. In order to
obtain an acceleration model of the PID effect, we have undertaken a set of PID experiments with variations of all
relevant environmental parameters (external voltage, temperature, humidity). Our experimental results enable us to
develop a consistent mathematical model of the PID effect in standard PV modules. Based on that, we suggest a
standard PID testing method and an acceptance criterion that should secure a stable power yield of PV systems under
field conditions.
Nanowire waveguide made from extremely anisotropic metamaterials
Creators: name: Huang, Y. J.
name: Lu, W. T.
name: Sridhar, S.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Optics (physics.optics)
subject: Classical Physics (physics.class-ph)
subject: FOS: Physical sciences

description: Exact solutions are obtained for all the modes of wave propagation along an anisotropic cylindrical waveguide. Closed-form expressions for the energy flow on the waveguide are also derived. For extremely anisotropic waveguide where the transverse permittivity is negative while the longitudinal permittivity is positive, only transverse magnetic (TM) and hybrid modes will propagate on the waveguide. At any given frequency the waveguide supports an infinite number of eigenmodes. Among the TM modes, at most only one mode is forward wave. The rest of them are backward waves which can have very large effective index. At a critical radius, the waveguide supports degenerate forward- and backward-wave modes with zero group velocity. These waveguides can be used as phase shifters and filters, and as optical buffers to slow down and trap light.
description: 11 pages, 15 figures, RevTex4
Opposing transcriptional programs of KLF5 and AR emerge during therapy for advanced prostate cancer.
Creators: name: Che, Meixia
name: Chaturvedi, Aashi
name: Munro, Sarah A
name: Pitzen, Samuel P
name: Ling, Alex
name: Zhang, Weijie
name: Mentzer, Josh
name: Ku, Sheng-Yu
name: Puca, Loredana
name: Zhu, Yanyun
name: Bergman, Andries M
name: Severson, Tesa M
name: Forster, Colleen
name: Liu, Yuzhen
name: Hildebrand, Jacob
name: Daniel, Mark
name: Wang, Ting-You
name: Selth, Luke A
name: Hickey, Theresa
name: Zoubeidi, Amina
name: Gleave, Martin
name: Bareja, Rohan
name: Sboner, Andrea
name: Tilley, Wayne
name: Carroll, Jason
name: Tan, Winston
name: Kohli, Manish
name: Yang, Rendong
name: Hsieh, Andrew C
name: Murugan, Paari
name: Zwart, Wilbert
name: Beltran, Himisha
name: Huang, R Stephanie
name: Dehm, Scott M
Publisher: name: Apollo - University of Cambridge Repository
Year: 2021
Subjects: Article
/631/45/612/822
/631/67/589/466
/13/106
/45/15
/45/91
/38/39
/38/89
/13/1
/13/105
/13/109
/42/44
article

description: Endocrine therapies for prostate cancer inhibit the androgen receptor (AR) transcription factor. In most cases, AR activity resumes during therapy and drives progression to castration-resistant prostate cancer (CRPC). However, therapy can also promote lineage plasticity and select for AR-independent phenotypes that are uniformly lethal. Here, we demonstrate the stem cell transcription factor Krüppel-like factor 5 (KLF5) is low or absent in prostate cancers prior to endocrine therapy, but induced in a subset of CRPC, including CRPC displaying lineage plasticity. KLF5 and AR physically interact on chromatin and drive opposing transcriptional programs, with KLF5 promoting cellular migration, anchorage-independent growth, and basal epithelial cell phenotypes. We identify ERBB2 as a point of transcriptional convergence displaying activation by KLF5 and repression by AR. ERBB2 inhibitors preferentially block KLF5-driven oncogenic phenotypes. These findings implicate KLF5 as an oncogene that can be upregulated in CRPC to oppose AR activities and promote lineage plasticity.
Isogeometric Residual Minimization Method (iGRM) with Direction Splitting for Non-Stationary Advection-Diffusion Problems
Creators: name: Los, Marcin
name: Munoz-Matute, Judit
name: Muga, Ignacio
name: Paszynski, Maciej
Publisher: name: arXiv
Year: 2021
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics

description: In this paper, we propose a novel computational implicit method, which we call Isogeometric Residual Minimization (iGRM) with direction splitting. The method mixes the benefits resulting from isogeometric analysis, implicit dynamics, residual minimization, and alternating direction solver. We utilize tensor product B-spline basis functions in space, implicit second order time integration schemes, residual minimization in every time step, and we exploit Kronecker product structure of the matrix to employ linear computational cost alternating direction solver. We implement an implicit time integration scheme and apply, for each space-direction, a stabilized mixed method based on residual minimization. We show that the resulting system of linear equations has a Kronecker product structure, which results in a linear computational cost of the direct solver, even using implicit time integration schemes together with the stabilized mixed formulation. We test our method on three advection-diffusion computational examples, including model ``membrane'' problem, the circular wind problem, and the simulations modeling pollution propagating from a chimney.
description: 30 pages, 15 figures
Limits on Magnetized Quark-Nugget Dark Matter from Episodic Natural Events
Creators: name: VanDevender, J. Pace
name: VanDevender, Aaron P.
name: Wilson, Peter
name: Hammel, Benjamin F.
name: McGinley, Niall
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: A quark nugget is a hypothetical dark-matter candidate composed of approximately equal numbers of up, down, and strange quarks. Most models of quark nuggets do not include effects of their intrinsic magnetic field. However, Tatsumi used a mathematically tractable approximation of the Standard Model of Particle Physics and found that the cores of magnetar pulsars may be quark nuggets in a ferromagnetic liquid state with surface magnetic field Bo between $10^{ 11}$ T and $10^{ 13}$ T. We have applied that result to quark-nugget dark matter. Previous work addressed the formation and aggregation of magnetized quark nuggets (MQNs) into a broad and magnetically stabilized mass distribution before they could decay and addressed their interaction with normal matter through their magnetopause, losing translational velocity while gaining rotational velocity and radiating electromagnetic energy. The two orders of magnitude uncertainty in Tatsumi estimate for Bo precludes the practical design of systematic experiments to detect MQNs through their predicted interaction with matter. In this paper, we examine episodic events consistent with a unique signature of MQNs. If they are indeed caused by MQNs, they constrain the most likely values of Bo to $1.65 x 10^{ 12}$ T $+/-$ $21\%$ and support the design of definitive tests of the MQN dark-matter hypothesis.
description: 33 pages, 14 figures, 2 tables
Impact of Increased Efficiency on the Cost of Wp
Creators: name: Allegrezza, M.
name: Giuliani, G.
name: Mileto, G.
name: Pietrafesa, M.
name: Summonte, C.
Publisher: name: WIP
Year: 2012
Subjects: PV - a Major Electricity Source
Markets

description: 27th European Photovoltaic Solar Energy Conference and Exhibition; 4523-4528
description: It is a diffused opinion that the possibility for PV energy to gain a prominent role in the scenario of
energy sources at a worldwide level is strictly linked, among other factors, to the increase of module efficiency, as
this is believed to directly result in a net reduction of costs. To verify this hypothesis, we analyzed the costs of smallmedium
PV plant installations, by separating the costs in power-related, area-related, and fixed costs, noting that the
efficiency of modules only enters in the determination of area-related costs.
We obtained that high efficiency is convenient only in the optimistic scenario of very moderate cost increase with
efficiency. The results are valid for the case of residential, roof installed PV plants.
Magnetic molecules created by hydrogenation of Polycyclic Aromatic Hydrocarbons
Creators: name: Verges, J. A.
name: Chiappe, G.
name: Louis, E.
name: Pastor-Abia, L.
name: SanFabian, E.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Atomic and Molecular Clusters (physics.atm-clus)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: Present routes to produce magnetic organic-based materials adopt a common strategy: the use of magnetic species (atoms, polyradicals, etc.) as building blocks. We explore an alternative approach which consists of selective hydrogenation of Polycyclic Aromatic Hydrocarbons. Self-Consistent-Field (SCF) (Hartree-Fock and DFT) and multi-configurational (CISD and MCSCF) calculations on coronene and corannulene, both hexa-hydrogenated, show that the formation of stable high spin species is possible. The spin of the ground states is discussed in terms of the Hund rule and Lieb's theorem for bipartite lattices (alternant hydrocarbons in this case). This proposal opens a new door to magnetism in the organic world.
description: 6 pages, 4 figures and 2 tables
Design and Numerical Analysis of Enhanced Cooling Techniques for a High Concentration Photovoltaic (HCPV) System
Creators: name: Theristis, M.
name: Sarmah, N.
name: Mallick, T.K.
name: O’Donovan, T.S.
Publisher: name: WIP
Year: 2012
Subjects: Material Studies, New Concepts and Ultra-High Efficiency
Terrestrial Concentrator Systems

description: 27th European Photovoltaic Solar Energy Conference and Exhibition; 260-265
description: A thermal model has been developed to predict the heat output of a PV cell, in order to examine the most
efficient and cost effective cooling system for a 500x concentrating PV cell. The worst case scenario (i.e. zero forced
convection from a flat surface) was selected in order to identify and measure the scale of the challenge. Different
geometries and materials of heat sinks were then designed and tested for passively cooling purposes of the High
Concentration Photovoltaic system. It is shown that passive cooling of a CPV system with CR of 500x is insufficient to
maintain the cells below 80°C, especially for high ambient temperatures. Numerical analysis and simulations in MatLAB
and COMSOL Multiphysics report on the level of cell’s surface temperature and convective heat transfer coefficient that
is required for the PV cell to operate below safe temperature limits.
The sooner the better: clinical and neural correlates of impulsive choice in Tourette disorder.
Creators: name: Atkinson-Clement, Cyril
name: De Liege, Astrid
name: Klein, Yanica
name: Beranger, Benoit
name: Valabregue, Romain
name: Delorme, Cecile
name: Roze, Emmanuel
name: Fernandez-Egea, Emilio
name: Hartmann, Andreas
name: Robbins, Trevor
name: Worbe, Yulia
Publisher: name: Apollo - University of Cambridge Repository
Year: 2021
Subjects: Article
/631/477/2811
/692/699/476
/631/378
/59/36
/59/57
article

description: Funder: Fondation pour la Recherche Médicale (Foundation for Medical Research in France); doi: https://doi.org/10.13039/501100002915
description: Reward sensitivity has been suggested as one of the central pathophysiological mechanisms in Tourette disorder. However, the subjective valuation of a reward by introduction of delay has received little attention in Tourette disorder, even though it has been suggested as a trans-diagnostic feature of numerous neuropsychiatric disorders. We aimed to assess delay discounting in Tourette disorder and to identify its brain functional correlates. We evaluated delayed discounting and its brain functional correlates in a large group of 54 Tourette disorder patients and 31 healthy controls using a data-driven approach. We identified a subgroup of 29 patients with steeper reward discounting, characterised by a higher burden of impulse-control disorders and a higher level of general impulsivity compared to patients with normal behavioural performance or to controls. Reward discounting was underpinned by resting-state activity of a network comprising the orbito-frontal, cingulate, pre-supplementary motor area, temporal and insular cortices, as well as ventral striatum and hippocampus. Within this network, (i) lower connectivity of pre-supplementary motor area with ventral striatum predicted a higher impulsivity and a steeper reward discounting and (ii) a greater connectivity of pre-supplementary motor area with anterior insular cortex predicted steeper reward discounting and more severe tics. Overall, our results highlight the heterogeneity of the delayed reward processing in Tourette disorder, with steeper reward discounting being a marker of burden in impulsivity and impulse control disorders, and the pre-supplementary motor area being a hub region for the delay discounting, impulsivity and tic severity.
Analysis of Mechanical Problems of String-Ribbon Interconnections in Photovoltaic Modules
Creators: name: Kraemer, F.
name: Wiese, S.
name: Peter, E.
name: Seib, J.
Publisher: name: WIP
Year: 2012
Subjects: Wafer-Based Silicon Solar Cells and Materials Technology
Manufacturing Issues and Processing

description: 27th European Photovoltaic Solar Energy Conference and Exhibition; 1162-1164
description: The paper describes the problems of interconnecting single solar cells with each other to create a
photovoltaic module. High power und low voltages demand the transport of high currents through the interconnection
wires. The resistance of the wiring is crucial, because it significantly influences the total module efficiency. This
problem may become even more critical as the cell efficiency increases. However, increasing the height of the
rectangular wires leads to significant mechanical problems, because the brittle silicon solar cells are prone to
breakage. Therefore innovations in interconnection technologies are needed to release mechanical stresses during the
assembly process.
FEM simulations were carried out in order to understand the major factors that can contribute to a significant stress
variation in the assembly process of photovoltaic modules. A parametric study was focused on the effect of upcoming
cell designs on the stresses generated in the assembly. The major geometric variations of future cell designs are a
reduced cell thickness and thicker interconnection wires. The influence of both variations can be checked by the
application of FEM simulations in order to prepare for mechanical problems before they appear in mass production
lines.
Strong electron-electron interactions in Si/SiGe quantum dots
Creators: name: Ercan, H. Ekmel
name: Coppersmith, S. N.
name: Friesen, Mark
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Interactions between electrons can strongly affect the shape and functionality of multi-electron quantum dots. The resulting charge distributions can be localized, as in the case of Wigner molecules, with consequences for the energy spectrum and tunneling to states outside the dot. The situation is even more complicated for silicon dots, due to the interplay between valley, orbital, and interaction energy scales. Here, we study two-electron wavefunctions in electrostatically confined quantum dots formed in a SiGe/Si/SiGe quantum well at zero magnetic field, using a combination of tight-binding and full-configuration-interaction (FCI) methods, and taking into account atomic-scale disorder at the quantum well interface. We model dots based on recent qubit experiments, which straddle the boundary between strongly interacting and weakly interacting systems, and display a rich and diverse range of behaviors. Our calculations show that strong electron-electron interactions, induced by weak confinement, can significantly suppress the low-lying, singlet-triplet (ST) excitation energy. However, when the valley-orbit interactions caused by interfacial disorder are weak, the ST splitting can approach its noninteracting value, even when the electron-electron interactions are strong and Wigner-molecule behavior is observed. These results have important implications for the rational design and fabrication of quantum dot qubits with predictable properties.
description: 22 pages, 11 figures
Pinch Points and Kasteleyn Transitions: How Spin Ice Changes its Entropy
Creators: name: Fennell, T.
name: Bramwell, S. T.
name: McMorrow, D. F.
name: Manuel, P.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: Complex disordered states - from liquids and glasses to exotic quantum matter - are ubiquitous in nature. Their key properties include finite entropy, power-law correlations and emergent organising principles. In spin ice, spin correlations are determined by an ice rules organising principle that stabilises a magnetic state with the same zero point entropy as water ice. The entropy can be manipulated with great precision by a magnetic field: with field parallel to the trigonal axis one obtains quasi two dimensional kagome ice which can be mapped onto a dimer model. Here we use a field tilted slightly away from the trigonal axis to control the dimer statistical weights and realise the unusual critical behaviour predicted by Kasteleyn. Neutron scattering on Ho2Ti2O7 reveals pinch point scattering that characterises the emergent gauge structure of kagome ice; diffuse peaks that shift with field, signaling the Kasteleyn physics; and an unusual critical point.
description: 17 pages, 5 figures. Significantly improved version appears in Nature Physics
Estimating lifetimes of uv-selected massive galaxies at $0.5 \le z \le 2.5$ in the cosmos/ultravista field through clustering analyses
Creators: name: Lin, Xiaozhi
name: Fang, Guanwen
name: Xue, Yongquan
name: Fan, Lulu
name: Kong, Xu
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present an estimation of lifetimes of massive galaxies with distinct UV colors at $0.5 \le z \le 2.5$ in the COSMOS/UltraVISTA field. After dividing the galaxy sample into subsamples of red sequence (RS), blue cloud (BC), and green valley (GV) galaxies in different redshift bins, according to their rest-frame extinction-corrected UV colors, we derive their lifetimes using clustering analyses. Several essentials that may influence the lifetime estimation have been explored, including the dark matter (DM) halo mass function (HMF), the width of redshift bin, the growth of DM halos within each redshift bin, and the stellar mass. We find that the HMF difference results in scatters of $\sim0.2$ dex on lifetime estimation; adopting a redshift bin width of $Δz = 0.5$ is good enough to estimate the lifetime; and no significant effect on lifetime estimation is found due to the growth of DM halos within each redshift bin. The galaxy subsamples with higher stellar masses generally have shorter lifetimes; however, the lifetimes among different subsamples at z > 1:5 tend to be independent of stellar mass. Consistently, the clustering-based lifetime for each galaxy subsample agrees well with that inferred using the spectral energy distribution modeling. Moreover, the lifetimes of the RS and BC galaxies also coincide well with their typical gas depletion timescales attributed to the consumption of star formation. Interestingly, the distinct lifetime behaviors of the GV galaxies at $z \le 1.5$ and $z>1.5$ can not be fully accounted for by their gas depletion timescales. Instead, this discrepancy between the lifetimes and gas depletion timescales of the GV galaxies suggests that there are additional physical processes, such as feedback of active galactic nuclei, accelerating the quenching of GV galaxies at high redshifts.
description: 19 pages, 13 figures, accept for publication in ApJ
ATLAS Deliverable 6.3 "Regional Marine Spatial Planning to support Blue Growth while accounting for climate change"
Creators: name: Grehan, A
name: Callery, O
name: Duran, P
name: Stirling, D
name: Campbell, G
name: Sacau, M
name: Garcia-Alegre, A
name: Morato, T
name: Rodrigues, L
name: Kenchington, E
name: Gafeira, J
name: Orejas, C
name: Rueda, JL
name: Hernandez Rosas, M
name: Henry, L-A
name: Roberts, M
name: Ross, S
name: van Oevelen, D
name: Egilsdóttir, H
name: Ragnarsson, S
name: Combes, M
name: Arnaud-Haond, S
name: Vaz, S
name: Menot, L
Publisher: name: Zenodo
Year: 2021

description: ATLAS Deliverable 6.3 "Regional Marine Spatial Planning to support Blue Growth while accounting for climate change"
The sequence TNNCT modulates transcription of a Drosophila Melanogaster tRNA ₄ gene
Creators: name: Sajjadi, Fereydoun G.
Publisher: name: University of British Columbia
Year: 2010

description: The transcription efficiency of transfer RNA genes is modulated by sequences contained in their 5'-flanking region. For a tRNA val₄ gene a pentanucleotide with the sequence TCGCT was identified between positions -33 and -38. I have previously proposed that this sequence may be involved in specifically determining the rate of transcription of this gene. A general form of this sequence, TNNCT was found associated with other Drosophila tRNA genes which showed high ill vitro transcription efficiency. To further elucidate the role of TCGCT in tRNA transcription, single and double base-pair changes were created in the sequence TCGCT using site-specific mutagenesis. Mutations in the nucleotides -38T, -35C and -34T showed decreased levels of transcription whereas nucleotide changes at the nucleotides -37C and -36G did not reduce template activity. Therefore the sequence which modulates transcription of the tRNAVal₄ gene does have the general form TNNCT. Competition experiments between the Val₄ mutant -38G.-35A and a tRNASer₇ gene showed the TNNCT mutant to be a better competitor for transcription than the wild type template. Experiments analyzing the time-course of transcription, the effects of temperature and the effects of ionic strength indicated that TNNCT was not involved in determining the efficiency of stable complex formation. It is proposed that the pentanucleotide is probably responsible for influencing the rate of initiation of transcription. A sequence TGCCT contained in the anticodon stem/loop region of the Val₄ gene was also mutagenized and shown to be involved in complex stability or the elongation of Val₄ tRNAs. Using deletion analysis of the 5'-flanking sequences of a tRNASer₇ gene, a second positive transcription regulatory element was delimited. This sequence was also found in the 5'-flanks of the tRNAVal₄ and a tRNAArg gene.
Drosophila ßHeavy-Spectrin is required in polarized ensheathing glia that form a diffusion-barrier around the neuropil.
Creators: name: Pogodalla, Nicole
name: Kranenburg, Holger
name: Rey, Simone
name: Rodrigues, Silke
name: Cardona, Albert
name: Klämbt, Christian
Publisher: name: Apollo - University of Cambridge Repository
Year: 2021
Subjects: Article
/631/378/87
/631/378/1341
/631/378/2596
/64/24
/38
/38/1
/38/89
/38/35
article

description: In the central nervous system (CNS), functional tasks are often allocated to distinct compartments. This is also evident in the Drosophila CNS where synapses and dendrites are clustered in distinct neuropil regions. The neuropil is separated from neuronal cell bodies by ensheathing glia, which as we show using dye injection experiments, contribute to the formation of an internal diffusion barrier. We find that ensheathing glia are polarized with a basolateral plasma membrane rich in phosphatidylinositol-(3,4,5)-triphosphate (PIP3) and the Na+/K+-ATPase Nervana2 (Nrv2) that abuts an extracellular matrix formed at neuropil-cortex interface. The apical plasma membrane is facing the neuropil and is rich in phosphatidylinositol-(4,5)-bisphosphate (PIP2) that is supported by a sub-membranous ßHeavy-Spectrin cytoskeleton. ßHeavy-spectrin mutant larvae affect ensheathing glial cell polarity with delocalized PIP2 and Nrv2 and exhibit an abnormal locomotion which is similarly shown by ensheathing glia ablated larvae. Thus, polarized glia compartmentalizes the brain and is essential for proper nervous system function.
Development of Optical Collimators for Accurate Calibration of Reference Solar Cells
Creators: name: Rodríguez-Outón, I.
name: Balenzategui, J.L.
name: Fabero, F.
name: Chenlo, F.
Publisher: name: WIP
Year: 2012
Subjects: Components for PV Systems
Standardisation

description: 27th European Photovoltaic Solar Energy Conference and Exhibition; 3700-3704
description: Design of optical collimators used for calibration of reference solar cells with the direct beam radiation
method is revised in order to evaluate the impact of their geometry in the cell calibration values and to correct
possible systematic errors. New prototypes of collimators have been developed in order to accurately match their
field of view (FOV), slope and limit angles to that of the primary reference devices used in calibration (absolute
cavity radiometers), and to take into account the different shape of the receiving surfaces (round shape for
pyrheliometers and square for reference solar cells). The new collimator’s performance is currently being tested in a
solar cell calibration campaign and the first experimental results are here presented. Small differences are appreciated
in the case of devices with narrower viewing angles.
J/psi production at RHIC-PHENIX
Creators: name: Oda, Susumu X.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: The J/psi is considered to be among the most important probes for the deconfined quark gluon plasma (QGP) created by relativistic heavy ion collisions. While the J/psi is thought to dissociate in the QGP by Debye color screening, there are competing effects from cold nuclear matter (CNM), feed-downs from excited charmonia (chi_c and psi') and bottom quarks, and regeneration from uncorrelated charm quarks. Measurements that can provide information to disentangle these effects are presented in this paper.
description: 4 pages, 3 figures, conference proceedings: the 20th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions, Quark Matter 2008, Jaipur (India), 4-10 February 2008, submitted to J. Phys. G: Nuclear and Particle Physics
Current Enhancement in p-i-n GaAs/Ge Solar Cells with a Tuned Superlattice, Embedded in the Mid-Region
Creators: name: Varonides, A.C.
Publisher: name: WIP
Year: 2012
Subjects: Material Studies, New Concepts and Ultra-High Efficiency
Fundamental Material Studies

description: 27th European Photovoltaic Solar Energy Conference and Exhibition; 482-486
description: In this communication, we propose high current solar cells through a multijunction solar cell. The host
device is a p-(Al)GaAs-(i)-GaAs-n(Ge) solar cell with the longest mid-layer (GaAs) containing a short
GaAs/Ge superlattice. Under illumination, modeling predicts a bulk short circuit current density of
18.5mA/cm2, however, for a 10-period tuned (1eV) and embedded superlattice in the intrinsic region of
the bulk device we find (a) Total currents of the composite cell at 22.82mA/cm2 (b) open-circuit voltage
at 1.045V and (c) collection efficiency increase from 17.12% to 20.98%.
title: Trust, testimony, and transmission: Essays in social virtue epistemology
Creators: name: Ólafsson, Ísak Andri
Publisher: name: University of Glasgow
Year: 2025

description: This thesis consists of five distinct essays within social virtue epistemology, each of which can stand independently, yet all engage with fundamental ideas surrounding trust, testimony, and knowledge transmission. The first two chapters explore knowledge transmission and testimony through a virtue epistemological lens, emphasising the challenges of accounting for testimonial knowledge while maintaining a connection between knowledge and credit. I introduce types of knowledge transmission that do not rely on joint agency or shared intentions, challenging a prominent view in virtue epistemology. I present a type of a credit view that can defend one of the fundamental doctrines of credit views, that knowledge always entails credit, from challenging counterexamples. Trust and testimony both facilitate connections between individuals, making them central to our understanding of how knowledge is shared in social contexts. The third chapter aims to further our understanding of the nature of trust by placing the spotlight on trust features that have gone largely unnoticed, namely, their temporal elements. By expanding on these features, we can make meaningful distinctions between instances of trust that have generally been considered interchangeable. These distinctions and related concepts highlight the subtle differences that meaningfully impact how we approach trust. In the fourth chapter, the focus shifts to epistemic groups in the context of gatekeeping. Epistemologists should be interested in trust, testimony, and transmission as they relate to individuals, but groups are an interesting epistemic subject in their own right. This chapter examines the distinct epistemic roles groups play in shaping the beliefs of their members, and how individuals can benefit from being part of a collective. I then present conditions for justified epistemic gatekeeping and consider what kinds of groups are most capable of fulfilling those conditions. In the last chapter, I consider how to define general artificial intelligence. It is difficult to place large language models within epistemology. At times, they act like epistemic agents, seemingly capable of producing and transmitting knowledge, yet they often appear incompetent and incapable of performing simple tasks. I propose a virtue-theoretic distinction between narrow and general artificial intelligence, in the hopes that it can contribute to our understanding of what makes AI trustworthy, and whether we should think of their predictions as knowledge.