cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Path-dependent initialization of a single quantum dot exciton spin in a nano-photonic waveguide
Creators: name: Coles, Rikki J.
name: Price, David M.
name: Royall, Ben
name: Clarke, Edmund
name: Skolnick, Maurice S.
name: Fox, Anthony M.
name: Makhonin, Maxim M.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Physics (quant-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We demonstrate a scheme for in-plane initialization and readout of a single exciton spin in an InGaAs quantum dot (QD) coupled to a GaAs nanobeam waveguide. The chiral coupling of the QD and the optical mode of the nanobeam enables spin initialization and readout fidelity approaching unity in magnetic field $B=1$ T and $\sim$0.9 without the field. We further show that this in-plane excitation scheme is independent of the incident excitation laser polarization and depends solely on the excitation direction. This scheme provides a robust in-plane spin excitation basis for a photon-mediated spin network for quantum information applications.
description: 5 pages, 3 figures
Festigkeits- und bruchmechanische Untersuchungen einer hochtemperaturbelasteten Forsterit-Keramik für die Anwendung in Festoxidbrennstoffzellen (SOFC)
Creators: name: Grudenik, Manuel
Publisher: name: Karlsruher Institut für Technologie (KIT)
Year: 2023
Subjects: Keramik
Forsterit
mechanische Eigenschaften
Bruchmechanik
Festoxidbrennstoffzelle
SOFC
Ceramic
Forsterite
mechanical properties
fracture mechanics
solid oxide fuel cell

description: In dieser Arbeit wurde eine dotierte Forsterit-Keramik (Mg2SiO4) im Hinblick auf ihre Eignung als Substratmaterial in einer Festoxidbrennstoffzelle untersucht. Aufgrund der relativ hohen Betriebstemperaturen von 700 - 800 °C fand zur Absicherung der thermomechanischen Stabilität der dotierten Forsterit-Keramik eine Analyse des Verhaltens unter simulierten SOFC-Betriebsbedingungen statt, wobei die Auswirkungen von Temperatur und Feuchtigkeit auf die Mikrostruktur und die mechanischen Eigenschaften besonders berücksichtigt wurden. Für den Ausgangszustand konnte eine Härte (870 HV), Bruchzähigkeit (1,25 MPa√m), charakteristische Festigkeit (110 MPa), der Weibull-Modul (8,4) und der E-Modul (172 GPa) ermittelt werden. Die Analyse der Mikrostruktur zeigt ein mehrphasiges Gefüge, bestehend aus der Forsteritmatrix, Poren und einer Al-, Zn-reichen Sekundärphase. Für die Untersuchungen des zeit- und temperaturabhängigen Materialverhaltens unter einer statisch thermischen Auslagerung bei 750 °C und 950 °C konnte keine wesentliche Veränderung der mechanischen Eigenschaften oder der Gefügestruktur ermittelt werden. Durch eine thermische Zyklierung bei einer Temperatur von 900 °C kommt es jedoch zu einem deutlichen Abfall (ca. 50%) der charakteristischen Festigkeit. In-Situ Untersuchungen bei erhöhten Temperaturen zeigen eine Zunahme der Bruchzähigkeit, während es bei erhöhten Temperaturen zu einer Abnahme der charakteristischen Festigkeit kommt. Durch fraktographische Analysen der Bruchflächen konnten größere, bruchauslösende Defekte festgestellt werden. Es lässt sich vermuten, dass es aufgrund herstellungsbedingter Verunreinigungen mit Al2O3 zur Bildung einer Zn(Al1,4Fe0,6)O4-Spinellphase kommt, welche zu einem abnormalen Kornwachstum führt. Bedingt durch thermische Eigenspannungen kommt es infolge dieser kritischen Defekte zu einem frühzeitigen Materialversagen, was vor allem die charakteristische Festigkeit in allen untersuchten Zuständen in einem starken Maße beeinflusst.
Revolutionary Ethics and Carceral Abolitionism: Ambivalences in Chicago Mutual Aid
Creators: name: Plunkett, Connor
Publisher: name: University of Chicago
Year: 2022
Subjects: subject: mutual aid
subject: abolitionism
subject: gentrification
subject: intersectionality
subject: anarchism
subject: Chicago
subject: carceral abolitionism
subject: segregation
subject: social space
subject: community organizing
subject: prefiguration
subject: solidarity
subject: digital technology

description: In response to the COVID-19 pandemic and to rampant anti-Black police violence, informal mutual aid networks have sprouted up around the world to help where the state and capitalism failed: providing aid to those most in need and building solidarity between all kinds of people in a local area. This article examines ambivalence in Chicago mutual aid practices through a collaborative ethnographic lens. In the first section of this article, I explore the ideals of Chicago mutual aid networks, which involve an abolitionist, intersectional, and prefigurative ethos aimed at creating "solidarity, not charity." Unfortunately, the mutual aid networks in Chicago have had difficulty living out this ethos fully. In the second section, I discuss three factors which prevent the networks from living out their ideals: 1) “Good Politics” lead to a culture of burnout, 2) capitalist space and gentrification condition who is welcome in the group, 3) technology and social practices alienate those unfamiliar with them. In the conclusion, I discuss parallels to Savannah Shange's "carceral progressivism" and outline some potential solutions.
Scoping Review. Hospital-led virtual health care for patients with acute infection
Creators: name: Hansen, Marian Normand
name: Sandreva, Tatjana
Publisher: name: Open Science Framework
Year: 2022
Subjects: subject: Medicine and Health Sciences
subject: Virtual ward, virtual health care, hospital at home, remote monitoring, telemedicine, acute infection, scoping review, outcome measures.

description: This scoping review aims to assess the reported evidence in clinical trials for hospital-led alternatives to in-patient care such as virtual health care (also known as virtual hospital at home, virtual ward or telemedicine) for patients with acute infection.
Quantum corrected polymer black hole thermodynamics: mass relations and logarithmic entropy correction
Creators: name: Mele, Fabio M.
name: Münch, Johannes
name: Pateloudis, Stratos
Publisher: name: Universität Regensburg
Year: 2022
Subjects: subject: GR black holes, gravity, quantum black holes, quantum gravity phenomenology
subject: 530 Physik

description: In this paper, we continue the analysis of the effective model of quantum Schwarz­schild black holes recently proposed by some of the authors in [1,2]. In the resulting quantum-corrected spacetime the central singularity is resolved by a black-to-white hole bounce, quantum effects become relevant at a unique mass-independent curvature scale, while they become negligible in the low curvature region near the horizon and classical Schwarzschild geometry is approached asymptotically. This is the case independently of the relation between the black and white hole masses, which are thus freely specifiable independent observables. A natural question then arises about the phenomenological implications of the resulting non-singular effective spacetime and whether some specific relation between the masses can be singled out from a phenomenological perspective. Here we focus on the thermodynamic properties of the effective polymer black hole and analyze the corresponding quantum corrections as functions of black and white hole masses. The study of the relevant thermodynamic quantities such as temperature, specific heat, and horizon entropy reveals that the effective spacetime generically admits an extremal minimal-sized configuration of quantum-gravitational nature characterized by vanishing temperature and entropy. For large masses, the classically expected results are recovered at leading order and quantum corrections are negligible, thus providing us with a further consistency check of the model. The explicit form of the corrections depends on the specific relationship among the masses. In particular, a first-order logarithmic correction to the black hole entropy is obtained for a quadratic mass relation. The latter corresponds to the case of proper finite-length effects which turn out to be compatible with a minimal length generalized uncertainty principle associated with an extremal Planck-sized black hole.
Validation of the CMS Magnetic Field Map
Creators: name: Klyukhin, V. I.
name: Amapane, N.
name: Ball, A.
name: Curé, B.
name: Gaddi, A.
name: Gerwig, H.
name: Mulders, M.
name: Calvelli, V.
name: Hervé, A.
name: Loveless, R.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: The Compact Muon Solenoid (CMS) is a general purpose detector, designed to run at the highest luminosity at the CERN Large Hadron Collider (LHC). Its distinctive features include a 4 T superconducting solenoid with 6-m-diameter by 12.5-m-length free bore, enclosed inside a 10,000-ton return yoke made of construction steel. The return yoke consists of five dodecagonal three-layered barrel wheels and four end-cap disks at each end comprised of steel blocks up to 620 mm thick, which serve as the absorber plates of the muon detection system. To measure the field in and around the steel, a system of 22 flux loops and 82 3-D Hall sensors is installed on the return yoke blocks. A TOSCA 3-D model of the CMS magnet is developed to describe the magnetic field everywhere outside the tracking volume measured with the field-mapping machine. The magnetic field description is compared with the measurements and discussed.
description: 7 pages, 5 figures, presented at 4th International Conference on Superconductivity and Magnetism 2014, April 27 - May 2, 2014, Antalya, Turkey. arXiv admin note: substantial text overlap with arXiv:1605.08778; text overlap with arXiv:1212.1657
On extreme transient events from rotating black holes and their gravitational wave emission
Creators: name: van Putten, Maurice H. P. M.
name: Della Valle, Massimo
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: The super-luminous object ASASSN-15lh (SN2015L) is an extreme event with a total energy $E_{rad}\simeq 1.1\times 10^{52}$ erg in black body radiation on par with its kinetic energy $E_k$ in ejecta and a late time plateau in the UV, that defies a nuclear origin. It likely presents a new explosion mechanism for hydrogen-deprived supernovae. With no radio emission and no H-rich environment we propose to identify $E_{rad}$ with dissipation of a baryon-poor outflow in the optically thick remnant stellar envelope produced by a central engine. By negligible time scales of light crossing and radiative cooling of the envelope, SN2015L's light curve closely tracks the evolution of this engine. We here model its light curve by the evolution of black hole spin, during angular momentum loss in Alvén waves to matter at the Inner Most Stable Circular Orbit (ISCO). The duration is determined by $σ=M_T/M$ of the torus mass $M_T$ around the black hole of mass $M$: $σ\sim 10^{-7}$ and $σ\sim 10^{-2}$ for SN2015L and, respectively, a long GRB. The observed electromagnetic radiation herein represents a minor output of the rotational energy $E_{rot}$ of the black hole, while most is radiated unseen in gravitational radiation. This model explains the high-mass slow-spin binary progenitor of GWB150914, as the remnant of two CC-SNe in an intra-day binary of two massive stars. This model rigorously predicts a change in magnitude $Δm\simeq 1.15$ in the light curve post-peak, in agreement with the light curve of SN2015L with no fine-tuning.
description: MNRAS, published online, doi: 10.1093/mnras/stw2496
Extended stellar substructure surrounding the Boötes I dwarf spheroidal galaxy
Creators: name: Roderick, T. A.
name: Mackey, A. D.
name: Jerjen, H.
name: Da Costa, G. S.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present deep stellar photometry of the Boötes I dwarf spheroidal galaxy in g and i band filters, taken with the Dark Energy Camera at Cerro Tololo in Chile. Our analysis reveals a large, extended region of stellar substructure surrounding the dwarf, as well as a distinct over-density encroaching on its tidal radius. A radial profile of the Boötes I stellar distribution shows a break radius indicating the presence of extra-tidal stars. These observations strongly suggest that Boötes I is experiencing tidal disruption, although not as extreme as that exhibited by the Hercules dwarf spheroidal. Combined with revised velocity dispersion measurements from the literature, we see evidence suggesting the need to review previous theoretical models of the Boötes I dwarf spheroidal galaxy.
description: 13 pages, 13 figures, accepted for publication in MNRAS
Report on the Humayma Excavation Project’s 2014 Survey of Petroglyphs and Quarries.
Creators: Reeves, M. Barbara
Harvey, Craig A.
Seymour, Brian
Publisher: name: University of Alberta Library
Year: 2018

In May 2014 the Ḥumayma Excavation Project (HEP) conducted a short survey in the sandstone hills and ridges to the west of Ḥumayma’s Nabataean to early Islamic settlement.
Stimulated emission of fast Alfvén waves within magnetically confined fusion plasmas
Creators: name: Cook, J W S
name: Dendy, R O
name: Chapman, S C
Publisher: name: arXiv
Year: 2016
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: A fast Alfvén wave with finite amplitude is shown to grow by a stimulated emission process that we propose for exploitation in toroidal magnetically confined fusion plasmas. Stimulated emission occurs while the wave propagates inward through the outer mid-plane plasma, where a population inversion of the energy distribution of fusion-born ions is observed to arise naturally. Fully nonlinear first principles simulations, which self-consistently evolve particles and fields under the Maxwell-Lorentz system, demonstrate this novel "alpha-particle channelling" scenario for the first time.
description: 5 pages, 4 figures
Chemoselective Reactivity of Bifunctional Cyclooctynes on Si(001)
Creators: name: Reutzel, Marcel
name: Münster, Niels
name: Lipponer, Marcus A.
name: Länger, Christian
name: Höfer, Ulrich
name: Koert, Ulrich
name: Dürr, Michael
Publisher: name: arXiv
Year: 2016
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Controlled organic functionalization of silicon surfaces as integral part of semiconductor technology offers new perspectives for a wide range of applications. The high reactivity of the silicon dangling bonds, however, presents a major hindrance for the first basic reaction step of such a functionalization, i.e., the chemoselective attachment of bifunctional organic molecules on the pristine silicon surface. We overcome this problem by employing cyclooctyne as the major building block of our strategy. Functionalized cyclooctynes are shown to react on Si(001) selectively via the strained cyclooctyne triple bond while leaving the side groups intact. The achieved selectivity originates from the distinctly different adsorption dynamics of the separate functionalities: A direct adsorption pathway is demonstrated for cyclooctyne as opposed to the vast majority of other organic functional groups. The latter ones react on Si(001) via a metastable intermediate which makes them effectively unreactive in competition with the direct pathway of cyclooctyne's strained triple bond.
description: 16 pages, 5 figures, TOC figure
Hiding Individuals and Communities in a Social Network
Creators: name: Waniek, Marcin
name: Michalak, Tomasz
name: Rahwan, Talal
name: Wooldridge, Michael
Publisher: name: arXiv
Year: 2016
Subjects: subject: Social and Information Networks (cs.SI)
subject: Physics and Society (physics.soc-ph)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences
subject: G.2.2; J.4
subject: 91D30 (Primary) 68T20 (Secondary)

description: The Internet and social media have fueled enormous interest in social network analysis. New tools continue to be developed and used to analyse our personal connections, with particular emphasis on detecting communities or identifying key individuals in a social network. This raises privacy concerns that are likely to exacerbate in the future. With this in mind, we ask the question: Can individuals or groups actively manage their connections to evade social network analysis tools? By addressing this question, the general public may better protect their privacy, oppressed activist groups may better conceal their existence, and security agencies may better understand how terrorists escape detection. We first study how an individual can evade "network centrality" analysis without compromising his or her influence within the network. We prove that an optimal solution to this problem is hard to compute. Despite this hardness, we demonstrate that even a simple heuristic, whereby attention is restricted to the individual's immediate neighbourhood, can be surprisingly effective in practice. For instance, it could disguise Mohamed Atta's leading position within the WTC terrorist network, and that is by rewiring a strikingly-small number of connections. Next, we study how a community can increase the likelihood of being overlooked by community-detection algorithms. We propose a measure of concealment, expressing how well a community is hidden, and use it to demonstrate the effectiveness of a simple heuristic, whereby members of the community either "unfriend" certain other members, or "befriend" some non-members, in a coordinated effort to camouflage their community.
description: 29 pages, 22 figures
Winding light beams along elliptical helical trajectories
Creators: name: Wen, Yuanhui
name: Chen, Yujie
name: Zhang, Yanfeng
name: Chen, Hui
name: Yu, Siyuan
Publisher: name: arXiv
Year: 2016
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Conventional caustic methods in real or Fourier space produced accelerating optical beams only with convex trajectories. We develop a superposition caustic method capable of winding light beams along non-convex trajectories. We ascertain this method by constructing a one-dimensional (1D) accelerating beam moving along a sinusoidal trajectory, and subsequently extending to two-dimensional (2D) accelerating beams along arbitrarily elliptical helical trajectories. We experimentally implement the method with a compact and robust integrated optics approach by fabricating micro-optical structures on quartz glass plates to perform the spatial phase and amplitude modulation to the incident light, generating beam trajectories highly consistent with prediction. The theoretical and implementation methods can in principle be extended to the construction of accelerating beams with a wide variety of non-convex trajectories, thereby opening up a new route of manipulating light beams for fundamental research and practical applications.
description: 8 pages, 10 figures
Novel pyrimidine Schiff bases and their selenium-containing nanoparticles as dual inhibitors of CDK1 and tubulin polymerase: design, synthesis, anti-proliferative evaluation, and molecular modelling
Creators: name: El-Kalyoubi, Samar
name: El-Sebaey, Samiha A.
name: El-Sayed, Ahmed A.
name: Abdelhamid, Moustafa S.
name: Agili, Fatimah
name: Elfeky, Sherin M.
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Biochemistry
subject: Cell Biology
subject: Pharmacology
subject: Biotechnology
classificationCode: 39999
subject: Chemical Sciences not elsewhere classified
classificationCode: 69999
subject: Biological Sciences not elsewhere classified
subject: Cancer

description: Nanotechnology-based strategies can overcome the limitations of conventional cancer therapies. Hence, novel series of pyrimidine Schiff bases (4–9) were employed in the synthesis of selenium nanoparticle forms (4NPs–9NPs). All selenium nano-sized forms exerted greater inhibitions than normal-sized compounds, far exceeding 5-fluorouracil activity. Compound 4 showed effective anti-proliferative activity against MCF-7(IC50 3.14 ± 0.04 µM), HepG-2(IC50 1.07 ± 0.03 µM), and A549(IC50 1.53 ± 0.01 µM) cell lines, while its selenium nanoform 4NPs showed excellent inhibitory effects, with efficacy increased by 96.52%, 96.45%, and 93.86%, respectively. Additionally, 4NPs outperformed 4 in selectivity against the Vero cell line by 4.5-fold. Furthermore, 4NPs exhibited strong inhibition of CDK1(IC50 0.47 ± 0.3 µM) and tubulin polymerase(IC50 0.61 ± 0.04 µM), outperforming 4 and being comparable to roscovitine (IC50 0.27 ± 0.03 µM) and combretastatin-A4(IC50 0.25 ± 0.01 µM), respectively. Moreover, both 4 and 4NPs arrested the cell cycle at G0/G1 phase and significantly forced the cells towards apoptosis. Molecular docking demonstrated that 4 and 4NPs were able to inhibit CDK1 and tubulin polymerase binding sites.
Ground-State Ordering of the $J_1$--$J_2$ Model on the Simple Cubic and Body-Centered Cubic Lattices
Creators: name: Farnell, D. J. J.
name: Götze, O.
name: Richter, J.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The $J_1$--$J_2$ Heisenberg model is a "canonical" model in the field of quantum magnetism in order to study the interplay between frustration and quantum fluctuations as well as quantum phase transitions driven by frustration. Here we apply the Coupled Cluster Method (CCM) to study the spin-half $J_1$--$J_2$ model with antiferromagnetic nearest-neighbor bonds $J_1 >0$ and next-nearest-neighbor bonds $J_2 >0$ for the simple cubic (SC) and body-centered cubic (BCC) lattices. In particular, we wish to study the ground-state ordering of these systems as a function of the frustration parameter $p=z_2J_2/z_1J_1$, where $z_1$ ($z_2$) is the number of nearest (next-nearest) neighbors. We wish to determine the positions of the phase transitions using the CCM and we aim to resolve the nature of the phase transition points. We consider the ground-state energy, order parameters, spin-spin correlation functions as well as the spin stiffness in order to determine the ground-state phase diagrams of these models. We find a direct first-order phase transition at a value of $p = 0.528$ from a state of nearest-neighbor Néel order to next-nearest-neighbor Néel order for the BCC lattice. For the SC lattice the situation is more subtle. CCM results for the energy, the order parameter, the spin-spin correlation functions and the spin stiffness indicate that there is no direct first-order transition between ground-state phases with magnetic long-range order, rather it is more likely that two phases with antiferromagnetic long-range are separated by a narrow region of a spin-liquid like quantum phase around $p=0.55$. Thus the strong frustration present in the $J_1$--$J_2$ Heisenberg model on the SC lattice may open a window for an unconventional quantum ground state in this three-dimensional spin model.
description: 22 pages, 8 figures
The assertive presidency – understanding preemptive executive pressure on foreign policy legislation in the US
Creators: name: Wiedekind, Jakob
Publisher: name: Hannover : Institutionelles Repositorium der Leibniz Universität Hannover
Year: 2023
Subjects: subject: American foreign policy
subject: interbranch dynamics
subject: presidents
subject: Amerikanische Außenpolitik
subject: Inter-Institutionelle Beziehungen
subject: Präsidenten
subject: Dewey Decimal Classification::300 | Sozialwissenschaften, Soziologie, Anthropologie::320 | Politik

description: The specter of an increasingly uneven distribution of power between the Executive Branch and Congress looms large in scholarship on the separation of powers in American government. This is particularly evident in the design and exercise of foreign policy. While the presidents’ use of legislative powers like the veto has been studied extensively, I argue that preemptive presidential interventions during the process of lawmaking are a subtler and less politically costly tool that is more important than scholars realized. This project focuses on American foreign policy lawmaking and examines the extent to which it is characterized by presidential assertiveness communicated to Congress through a hitherto understudies tool of executive intervention. Specifically, I seek to understand how contemporary presidents use Statements of Administration Policy (SAPs), a relatively new class of executive communications designed to preemptively intervene in key legislation as it is drafted in Congress. Delivered at a crucial intervention point along the legislative process, these communications provide a key opportunity for presidents to challenge specific provisions. Embedded in the broader discourse on struggling congressional checks on the executive, this project fills a gap in the understanding of the dynamics that shape the balance of power between Congress and the president. I find that interbranch confrontations increased significantly after the critical juncture of 9/11 and that Congress gradually expanded the use of its authorization leverage over time. In addition, two contextual predictors of increasing presidential assertiveness in preemptive messages to Congress stand out: divided government and presidential election years. My results indicate that presidents still cannot achieve many of their foreign policy goal without negotiating with Congress within contested bargaining procedures. Overall, my dissertation makes three principal contributions to the ongoing research on domestic underpinnings of US foreign policy: First, my findings quality the image of unchecked presidential discretion and highlight the continuous relevance of interbranch contestation in foreign policy. Second, I show that the mechanisms of change as laid out by historical institutionalism are useful for explaining long-term shifts in interbranch dynamics. Third, I introduce a novel assertiveness-score based on a relatively new source of presidential position language, which can be adapted for other research purposes.
Quantum Thermodynamics and Quantum Entanglement Entropies in an Expanding Universe
Creators: name: Farahmand, Mehrnoosh
name: Mohammadzadeh, Hosein
name: Mehri-Dehnavi, Hossein
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Physics (quant-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We investigate an asymptotically spatially flat Robertson-Walker spacetime from two different perspectives. First, using von Neumann entropy, we evaluate the entanglement generation due to the encoded information in spacetime. Then, we work out the entropy of particle creation based on the quantum thermodynamics of the scalar field on the underlying spacetime. We show that the general behavior of both entropies are the same. Therefore, the entanglement can be applied to the customary quantum thermodynamics of the universe. Also, using these entropies, we can recover some information about the parameters of spacetime.
description: 10 pages, 11 figures
Interferometric Motion Detection in Atomic Layer 2D Nanostructures: Visualizing Signal Transduction Efficiency and Optimization Pathways
Creators: name: Wang, Zenghui
name: Feng, Philip X. -L.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Atomic layer crystals are emerging building blocks for enabling new two-dimensional (2D) nanomechanical systems, whose motions can be coupled to other attractive physical properties in such 2D systems. Optical interferometry has been very effective in reading out the infinitesimal motions of these 2D structures and spatially resolving different modes. To quantitatively understand the detection efficiency and its dependence on the device parameters and interferometric conditions, here we present a systematic study of the intrinsic motion responsivity in 2D nanomechanical systems using a Fresnel-law-based model. We find that in monolayer to 14-layer structures, MoS2 offers the highest responsivity among graphene, h-BN, and MoS2 devices and for the three commonly used visible laser wavelengths (633, 532, and 405nm). We also find that the vacuum gap resulting from the widely used 300nm-oxide substrate in making 2D devices, fortunately, leads to close-to-optimal responsivity for a wide range of 2D flakes. Our results elucidate and graphically visualize the dependence of motion transduction responsivity upon 2D material type and number of layers, vacuum gap, oxide thickness, and detecting wavelength, thus providing design guidelines for constructing 2D nanomechanical systems with optimal optical motion readout.
description: 8 Figures, 18 Pages
Modal formulation for diffraction by absorbing photonic crystal slabs
Creators: name: Dossou, Kokou B.
name: Botten, Lindsay C.
name: Asatryan, Ara A.
name: Sturmberg, Björn C. P.
name: Byrne, Michael A.
name: Poulton, Christopher G.
name: McPhedran, Ross C.
name: de Sterke, C. Martijn
Publisher: name: arXiv
Year: 2016
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: A finite element-based modal formulation of diffraction of a plane wave by an absorbing photonic crystal slab of arbitrary geometry is developed for photovoltaic applications. The semi-analytic approach allows efficient and accurate calculation of the absorption of an array with a complex unit cell. This approach gives direct physical insight into the absorption mechanism in such structures, which can be used to enhance the absorption. The verification and validation of this approach is applied to a silicon nanowire array and the efficiency and accuracy of the method is demonstrated. The method is ideally suited to studying the manner in which spectral properties (e.g., absorption) vary with the thickness of the array, and we demonstrate this with efficient calculations which can identify an optimal geometry.
description: Accepted by Journal of the Optical Society of America A
Can background cosmology hold the key for modified gravity tests?
Creators: name: Ceron-Hurtado, Juan J.
name: He, Jian-hua
name: Li, Baojiu
Publisher: name: arXiv
Year: 2016
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Modified gravity theories are a popular alternative to dark energy as a possible explanation for the observed accelerating cosmic expansion, and their cosmological tests are currently an active research field. Studies in recent years have been increasingly focused on testing these theories in the nonlinear regime, which is computationally demanding. Here we show that, under certain circumstances, a whole class of theories can be ruled out by using background cosmology alone. This is possible because certain classes of models (i) are fundamentally incapable of producing specific background expansion histories, and (ii) said histories are incompatible with local gravity tests. As an example, we demonstrate that a popular class of models, $f(R)$ gravity, would not be viable if observations suggest even a slight deviation of the background expansion history from that of the $Λ$CDM paradigm.
description: 6 pages, 3 figures; accepted for publication in Phys. Rev. D
General finite-size effects for zero-entropy states in one-dimensional quantum integrable models
Creators: name: Eliëns, I. S.
name: Caux, J. -S.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mathematical Physics (math-ph)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We present a general derivation of the spectrum of excitations for gapless states of zero entropy density in Bethe ansatz solvable models. Our formalism is valid for an arbitrary choice of bare energy function which is relevant to situations where the Hamiltonian for time evolution differs from the Hamiltonian in a (generalized) Gibbs ensemble, i.e. out of equilibrium. The energy of particle and hole excitations, as measured with the time-evolution Hamiltonian, is shown to include additional contributions stemming from the shifts of the Fermi points that may now have finite energy. The finite-size effects are also derived and the connection with conformal field theory discussed. The critical exponents can still be obtained from the finite-size spectrum, however the velocity occurring here differs from the one in the constant Casimir term. The derivation highlights the importance of the phase shifts at the Fermi points for the critical exponents of asymptotes of correlations. We generalize certain results known for the ground state and discuss the relation to the dressed charge (matrix). Finally, we discuss the finite-size corrections in the presence of an additional particle or hole which are important for dynamical correlation functions.
PREVALENCE AND IDENTIFICATION OF FROZEN SHOULDER PATIENTS WITH DIABETES MELLITUS - AN EMPIRICAL STUDY
Creators: name: K. Venkata Naga Prahalada* & K. Sudarshan**
Publisher: name: Zenodo
Year: 2024

description: Frozen shoulder is a constellation of symptoms like un-controlled pain. It is one of the musculoskeletal complications in patients with type 1 and type 2 diabetes that can be particularly debilitating. Researcher carried out this cross-sectional study on 579 patients with both type 1 and type 2 diabetes who had registered at the Diabetes Care Center Kadapa district, Andhra Pradesh, India. The study was conducted from January 2023 to December 2023. A structured questionnaire was designed and the responses of patients were recorded after informed verbal and written consent. The questionnaire outlined the key factors that can lead to a higher frequency of Frozen shoulder in patients with type 1 and type 2 diabetes. Among the 579 patients who attended the Diabetic care centre, Kadapa district, Andhra Pradesh, 216 individuals (37.3%) suffered from frozen shoulder. Females (n=126) were more commonly affected than males (n = 90). The present study shows that the prevalence of frozen shoulder is higher in patients with diabetes residing in Kadapa district. It can be attributed to socioeconomic status, lack of awareness, and poor blood glycemic control. Mass awareness campaigns, especially for male and female patients with type 1 and type 2 diabetes, are required to be initiated to create awareness about the disease and to facilitate early diagnosis and appropriate management. In-depth studies are needed to further explore the association between frozen shoulder and type 1 and type 2 diabetic patients.
Alzheimer's Disease Diagnostics by Adaptation of 3D Convolutional Network
Creators: name: Hosseini-Asl, Ehsan
name: Keynto, Robert
name: El-Baz, Ayman
Publisher: name: arXiv
Year: 2016
Subjects: subject: Machine Learning (cs.LG)
subject: Neurons and Cognition (q-bio.NC)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences
subject: FOS: Biological sciences

description: Early diagnosis, playing an important role in preventing progress and treating the Alzheimer\{'}s disease (AD), is based on classification of features extracted from brain images. The features have to accurately capture main AD-related variations of anatomical brain structures, such as, e.g., ventricles size, hippocampus shape, cortical thickness, and brain volume. This paper proposed to predict the AD with a deep 3D convolutional neural network (3D-CNN), which can learn generic features capturing AD biomarkers and adapt to different domain datasets. The 3D-CNN is built upon a 3D convolutional autoencoder, which is pre-trained to capture anatomical shape variations in structural brain MRI scans. Fully connected upper layers of the 3D-CNN are then fine-tuned for each task-specific AD classification. Experiments on the CADDementia MRI dataset with no skull-stripping preprocessing have shown our 3D-CNN outperforms several conventional classifiers by accuracy. Abilities of the 3D-CNN to generalize the features learnt and adapt to other domains have been validated on the ADNI dataset.
description: This paper is accepted for publication at IEEE ICIP 2016 conference
K2P$^2$: Reduced data from campaigns 0-4 of the K2 mission
Creators: name: Handberg, R.
name: Lund, M. N.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: Context: After the loss of a second reaction wheel the Kepler mission was redesigned as the K2 mission, pointing towards the ecliptic and delivering data for new fields approximately every 80 days. The steady flow of data obtained with a reduced pointing stability calls for dedicated pipelines for extracting light curves and correcting these for use in, e.g., asteroseismic analysis. Aims: We provide corrected light curves for the K2 fields observed until now (campaigns 0-4), and provide a comparison with other pipelines for K2 data extraction/correction. Methods: Raw light curves are extracted from K2 pixel data using the "K2-pixel-photometry" (K2P$^2$) pipeline, and corrected using the KASOC filter. Results: The use of K2P$^2$ allows for the extraction of the order of 90.000 targets in addition to 70.000 targets proposed by the community - for these, other pipelines provide no data. We find that K2P$^2$ in general performs as well as, or better than, other pipelines for the tested metrics of photometric quality. In addition to stars, pixel masks are properly defined using K2P$^2$ for extended objects such as galaxies for which light curves are also extracted.
description: Accepted for publication in Astronomy and Astrophysics
Quantification of uncertainty in first-principles predicted mechanical properties of solids: Application to solid ion conductors
Creators: name: Ahmad, Zeeshan
name: Viswanathan, Venkatasubramanian
Publisher: name: arXiv
Year: 2016
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: Computationally-guided material discovery is being increasingly employed using a descriptor-based screening through the calculation of a few properties of interest. A precise understanding of the uncertainty associated with first principles density functional theory calculated property values is important for the success of descriptor-based screening. Bayesian error estimation approach has been built-in to several recently developed exchange-correlation functionals, which allows an estimate of the uncertainty associated with properties related to the ground state energy, for e.g. adsorption energies. Here, we propose a robust and computationally efficient method for quantifying uncertainty in mechanical properties, which depends on the derivatives of the energy. The procedure involves calculating the energy around the equilibrium cell volume with different strains and fitting the obtained energies to the corresponding energy-strain relationship. At each strain, we use instead of a single energy, an ensemble of energies, giving us an ensemble of fits and thereby, an ensemble of mechanical properties associated with each fit, whose spread can be used to quantify its uncertainty. The generation of ensemble of energies is only a post-processing step involving a perturbation of parameters of the exchange-correlation functional and solving for the energy non-self consistently. The proposed method is computationally efficient and provides a more robust uncertainty estimate compared to the approach of self-consistent calculations employing several different exchange-correlation functionals. We demonstrate the method by calculating the uncertainty bounds for Si using the developed method. We show that the calculated uncertainty bounds the property values obtained using three different GGA functionals: PBE, PBEsol and RPBE.
description: 7 pages, 3 figures, 3 tables
Magnetism in Sr$_{2}$CrMoO$_{6}$: A combined abinitio and model study
Creators: name: Sanyal, Prabuddha
name: Halder, Anita
name: Si, Liang
name: Wallerberger, Markus
name: Held, Karsten
name: Saha-Dasgupta, Tanusri
Publisher: name: arXiv
Year: 2016
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Using a combination of first-principles density functional theory (DFT) calculations and exact diagonalization studies of a first-principles derived model, we carry out a microscopic analysis of the magnetic properties of the half-metallic double perovskite compound, Sr$_2$CrMoO$_6$, a sister compound of the much discussed material Sr$_2$FeMoO$_6$. The electronic structure of Sr$_2$CrMoO$_6$, though appears similar to Sr$_2$FeMoO$_6$ at first glance, shows non trivial differences with that of Sr$_2$FeMoO$_6$ on closer examination. In this context, our study highlights the importance of charge transfer energy between the two transition metal sites. The change in charge transfer energy due to shift of Cr $d$ states in Sr$_2$CrMoO$_6$ compared to Fe $d$ in Sr$_2$FeMoO$_6$ suppresses the hybridization between Cr $t_{2g}$ and Mo $t_{2g}$. This strongly weakens the hybridization-driven mechanism of magnetism discussed for Sr$_2$FeMoO$_6$. Our study reveals that, nonetheless, the magnetic transition temperature of Sr$_2$CrMoO$_6$ remains high since additional superexchange contribution to magnetism arises with a finite intrinsic moment developed at the Mo site. We further discuss the situation in comparison to another related double perovskite compound, Sr$_2$CrWO$_6$. We also examine the effect of correlation beyond DFT, using dynamical mean field theory (DMFT).
description: 8 pages, 3 figures
Bow shock nebulae of hot massive stars in a magnetized medium
Creators: name: Meyer, D. M. -A.
name: Mignone, A.
name: Kuiper, R.
name: Raga, A.
name: Kley, W.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: A significant fraction of OB-type, main-sequence massive stars are classified as runaway and move supersonically through the interstellar medium (ISM). Their strong stellar winds interact with their surroundings where the typical strength of the local ISM magnetic field is about 3.5-7 micro-G, which can result in the formation of bow shock nebulae. We investigate the effects of such magnetic fields, aligned with the motion of the flow, on the formation and emission properties of these circumstellar structures. Our axisymmetric, magneto-hydrodynamical simulations with optically-thin radiative cooling, heating and anisotropic thermal conduction show that the presence of the background ISM magnetic field affects the projected optical emission our bow shocks at Ha and [OIII] lambda 5007 which become fainter by about 1-2 orders of magnitude, respectively. Radiative transfer calculations against dust opacity indicate that the magnetic field slightly diminishes their projected infrared emission and that our bow shocks emit brightly at 60 micron. This may explain why the bow shocks generated by ionizing runaway massive stars are often difficult to identify. Finally, we discuss our results in the context of the bow shock of Zeta Ophiuchi and we support the interpretation of its imperfect morphology as an evidence of the presence of an ISM magnetic field not aligned with the motion of its driving star.
description: Accepted by MNRAS, 21 pages, 13 figures
FoodRoof: Providing High Quality Foods to Consumers from The Roof Garden Using E-commerce and Bicycle-based Delivery Approach
Creators: name: Kabir, S. Rayhan
name: Shanjida Akhtar Riya Moni
name: Mahfuzul Hasan
Publisher: name: Zenodo
Year: 2022
Subjects: Roof garden
Rooftop Farm
Roof Farming
E-commerce
Price Hikes
Price Gouging
Inflation
Green City
Sustainable Development
Poverty

description: Urbanization is increasing day by day which is having a negative impact on the environment. Also, the amount of cultivable land is declining due to population growth and urbanization. On the other hand, arable land and farms are located far away from the city. Therefore, vehicle communication is a very important issue for providing safe food to the people of the city. Roof gardening or roof farming is becoming very popular day by day and it is a good aspect for green city and environment. In addition to agricultural work on the roof of the building, domestic animals can be reared on the roof. Fish farming is also done using the Biofloc method on roofs. We are three young beginner software engineers; We plan to work with a web application and building-to-building small vehicle-based food delivery system where food can be delivered from one roof farm to other nearby buildings. By doing this, those who do roof farming will benefit financially and roof farming will increase. On the other hand, this will alleviate the problem of food supply from remote areas. We are developing an E-commerce and a small zone-based supply chain system. The information about those who do roof farming will be on our website. He or she will constantly upload the food products of the roof garden to our website. This information will be marketed in the surrounding buildings. People in the vicinity can contact the owner of the roof farm directly to buy any food product or buy it through our e-commerce. We will use a small vehicle such as a bicycle or a motorcycle to deliver the products of one roof garden to another building. In our team, Mr. S. Raihan Kabir is working on the technical part of this project, research, and business process. Mr. Mahfuzul Hasan is fully focused on website development. Mrs. Shanjida Akhtar Riya Moni is trying to focus on the product delivery operation. We believe, that one day our startup becomes very popular and it will create a good impact on society and the environment.
description: This presentation is also found on the Course Hero website. Link: https://www.coursehero.com/file/89590324/Hult-Prize-FoodRoofpptx/
Re-acceleration model for the `Sausage' Radio Relic
Creators: name: Kang, Hyesung
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: The Sausage radio relic is the arc-like radio structure in the cluster CIZA J2242.8+5301, whose observed properties can be best understood by synchrotron emission from relativistic electrons accelerated at a merger-driven shock. However, there remain a few puzzles that cannot be explained by the shock acceleration model with only in-situ injection. In particular, the Mach number inferred from the observed radio spectral index, $M_{\rm radio}\approx 4.6$, while the Mach number estimated from X-ray observations, $M_{\rm X-ray}\approx 2.7$. In an attempt to resolve such a discrepancy, here we consider the re-acceleration model in which a shock of $M_s\approx 3$ sweeps through the intracluster gas with a pre-existing population of relativistic electrons. We find that observed brightness profiles at multi frequencies provide strong constraints on the spectral shape of pre-existing electrons. The models with a power-law momentum spectrum with the slope, $s\approx 4.1$, and the cutoff Lorentz factor, $γ_{e,c}\approx 3-5\times 10^4$ can reproduce reasonably well the observed spatial profiles of radio fluxes and integrated radio spectrum of the Sausage relic. The possible origins of such relativistic electrons in the intracluster medium remain to be investigated further.
description: 12 pages, 5 figures, submittted to JKAS