cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Axially symmetric rotating traversable wormholes
Creators: name: Kuhfittig, Peter K. F.
Publisher: name: arXiv
Year: 2004
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: This paper generalizes the static and spherically symmetric traversable wormhole geometry to a rotating axially symmetric one with a time-dependent angular velocity by means of an exact solution. It was found that the violation of the weak energy condition, although unavoidable, is considerably less severe than in the static spherically symmetric case. The radial tidal constraint is more easily met due to the rotation. Similar improvements are seen in one of the lateral tidal constraints. The magnitude of the angular velocity may have little effect on the weak energy condition violation for an axially symmetric wormhole. For a spherically symmetric one, however, the violation becomes less severe with increasing angular velocity. The time rate of change of the angular velocity, on the other hand, was found to have no effect at all. Finally, the angular velocity must depend only on the radial coordinate, confirming an earlier result.
description: 17 pages, AMSTeX
Impact of Fe0 amendment on methylene blue discoloration by sand columns
Creators: name: Miyajima, K.
name: Noubactep, C.
Publisher: name: FID GEO
Year: 2013

description: The influence of metallic iron (Fe0) amendment on the efficiency of sand to discolor a 2.0 mg L-1 methylene blue (MB) solution was investigated in column studies. MB was used as an indicator to identify the optimum Fe0/sand ratio for efficient filtration systems. Columns contained 0, 100 or 200 g of a Fe0 material. The volumetric proportion of Fe0 in the reactive layer of the columns with 100 g of material varied from 10 to 100 %. Results showed that, Fe0 amendment significantly impaired MB discoloration by sand for experiments lasting for up to 132 days. Early MB breakthrough in Fe0/sand columns delineated the paramount importance of particle cementation, which has caused preferential flow with a negative impact on discoloration efficiency. The most efficient Fe0/sand mixtures were the ones with 30 to 50 % Fe0 (v/v). These volumetric ratios correspond 33 to 41 % weight ratios showing that the commonly used 1:1 weight ratio (50 %) may not be optimal. Further research with compounds exhibiting different affinities to both Fe0 and sand is needed before this observation can be generalized.
StarTrack predictions of the stochastic gravitational-wave background from compact binary mergers
Creators: name: Périgois, C.
name: Belczynski, C.
name: Bulik, T.
name: Regimbau, T.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We model the gravitational-wave background created by double compact objects from isolated binary evolution across cosmic time using the \textbf{\textit{StarTrack}} binary population code. We include population I/II stars as well as metal-free population III stars. Merging and non-merging double compact object binaries are taken into account. In order to model the low frequency signal in the band of the space antenna LISA, we account for the evolution of the redshift and the eccentricity. We find an energy density of $Ω_{GW} \sim 1.0 \times 10^{-9}$ at the reference frequency of 25 Hz for population I/II only, making the background detectable at 3 $σ$ after about 7 years of observation with the current generation of ground based detectors, such as LIGO, Virgo and Kagra, operating at design sensitivity. The contribution from population III is one order of magnitude below the population I/II for the total background, but dominates the residual background, after detected sources have been removed, in 3G detectors. It modifies the shape of the spectrum which starts deviating from the usual power law $Ω_{GW}(f) \sim f^{2/3}$ after $\sim 10$ Hz. The contribution from the population of non merging binaries, on the other hand, is negligible, being orders of magnitude below. Finally, we observe that the eccentricity has no impact in the frequency band of LISA or ground based detectors.
description: new version: 15 pages, 5 figures, 3 tables, published in PRD
title: The English boys boarding preparatory school, 1914-1940
Creators: name: Austin, Jonathan Edward
Publisher: name: The Open University
Year: 1995

description: This thesis is a detailed study of a long-standing English institution. The preparatory school is an integral component of the education system of Britain's wealthier classes and has influenced the lives of many of this country's greatest men. The popular conception of the inter-war prep school is that of an unpleasant world of bullies, beatings and cold baths. This notion stems from the writings of a few influential authors and may not represent the reality. This thesis seeks to examine this conception by comparing it with a detailed description of the institution drawn from a wide range of sources. The study has utilised information from memoirs as well as interviews conducted with those who attended or taught at a prep school before the last war. Contemporary articles and reports have been' supplemented by knowledge drawn from the schools own archives. One objective of-the thesis has been to use these sources in their original form. The prep school is defined and placed in its historical context. The nature of the popular conception is clarified before every aspect of prep school life in this period is then examined. The study considers the curriculum, games and staff. There is a detailed account of daily life. Rules, organisation and discipline are described and the ethos of the institution explored. Parents and relationships with son and school are also considered. Finally there is an attempt to identify the long term effect of the prep school experience.
Petrology, Geochemistry, and Geodynamic Implications of Basaltic Dyke Swarms from the Southern Continental Part of the Cameroon Volcanic Line, Central Africa
Creators: name: Tchouankoue, Jean Pierre
name: Wambo, Nicole Armelle Simeni
name: Dongmo, Armand Kagou
name: Wörner, Gerhard
Publisher: name: FID GEO
Year: 2012

description: Basaltic dyke swarms in the southern continental part of the Cameroon Volcanic Line (Bangangte, Dschang, Manjo areas) are tholeiitic in composition with 46 to 50 wt.% SiO 2 and have moderate Mg-numbers (53–59), medium TiO 2 contents (1.48–2,05 wt.%), and flat to mildly enriched incompatible trace element patterns. Comparison with trace element patterns of representative Cenozoic basaltic rocks of the Cameroon Volcanic Line (Bana anorogenic complex, Mt. Bambouto, Adamawa Plateau basalts) indicates that these dykes are less enriched in light REE and show different incompatible trace element ratios (La/Yb: 5.7 to 8.6; Zr/Nb: 7.6 to 12.0; Ba/Th: 87.7 to 93.3). The trace element patterns of the dykes and their Sr- and Nd- isotope compositions, however, are similar to those of the pre-Cenozoic volcanic rocks of the Benue Trough in Nigeria. Our data therefore suggest that these dykes represent the magmatic history related to the break-up of Africa and South America and are unrelated to the Tertiary volcanism of the Cameroon Line.
FLUORESCENCE QUENCHING OF RUTHENIUM TRIS COMPLEX IN PHOTODYNAMIC THERAPY
Creators: name: DATTA, JAYDIP
Publisher: name: figshare
Year: 2020
Subjects: subject: 30201 Bioinorganic Chemistry
subject: FOS: Chemical sciences

description: In this note we wish to report the Photo Dynamic Application of STERN VOLMER EQUATION relating to Quenching rate constant to predict photo-dynamic therapy ( PDT ).
Discrete Painlevé equations and random matrix averages
Creators: name: Forrester, P. J.
name: Witte, N. S.
Publisher: name: arXiv
Year: 2003
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: The $τ$-function theory of Painlevé systems is used to derive recurrences in the rank $n$ of certain random matrix averages over U(n). These recurrences involve auxilary quantities which satisfy discrete Painlevé equations. The random matrix averages include cases which can be interpreted as eigenvalue distributions at the hard edge and in the bulk of matrix ensembles with unitary symmetry. The recurrences are illustrated by computing the value of a sequence of these distributions as $n$ varies, and demonstrating convergence to the value of the appropriate limiting distribution.
description: 25 pages
Whole-genome sequences of two new caballeronia strains isolated from cryoturbated peat circles of the permafrost-affected eastern european tundra
Creators: name: Hetz, Stefanie A.
name: Poehlein, Anja
name: Horn, Marcus A.
Publisher: name: Washington, DC : American Society for Microbiology
Year: 2020
Subjects: subject: bacterial DNA
subject: bacterial enzyme
subject: DNA
subject: genomic DNA
subject: high molecular weight DNA
subject: napA protein
subject: narG protein
subject: nasA protein
subject: nirBD protein
subject: nitrate
subject: nitrate reductase
subject: norV protein
subject: oxidoreductase
subject: oxygen
subject: RNA 16S
subject: unclassified drug
subject: bacterial chromosome
subject: bacterial genome
subject: bacterial strain
subject: bacterium isolate
subject: bacterium isolation
subject: Caballeronia mineralivorans
subject: Caballeronia strain SBC1
subject: Caballeronia strain SBC2
subject: cold
subject: environment
subject: Gram negative facultatively anaerobic rods
subject: illumina sequencing
subject: maximum likelihood method
subject: microbial respiration
subject: nanopore sequencing
subject: neighbor joining method
subject: new species
subject: nitrogen cycling
subject: nonhuman
subject: nucleotide sequence
subject: operon
subject: permafrost
subject: pH
subject: plasmid
subject: shotgun sequencing
subject: tundra
subject: whole genome sequencing
subject: Dewey Decimal Classification::500 | Naturwissenschaften::570 | Biowissenschaften, Biologie
subject: Dewey Decimal Classification::600 | Technik::610 | Medizin, Gesundheit

description: Annotated genomes of Caballeronia strains SBC1 and SBC2 from acidic permafrost suggest a new species with a facultative lifestyle via oxygen and nitrate respiration. Thus, a contribution to nitrogen cycling in cold and low-pH environments is anticipated. ¬© 2020 Hetz et al. This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International license.
The density of the ISE and local limit laws for embedded trees
Creators: name: Bousquet-Mélou, Mireille
name: Janson, Svante
Publisher: name: arXiv
Year: 2005
Subjects: subject: Probability (math.PR)
subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 60C05 (Primary), 05A15, 05C05 (Secondary)

description: It has been known for a few years that the occupation measure of several models of embedded trees converges, after a suitable normalization, to the random measure called ISE (Integrated SuperBrownian Excursion). Here, we prove a local version of this result: ISE has a (random) Hölder continuous density, and the vertical profile of embedded trees converges to this density, at least for some such trees. As a consequence, we derive a formula for the distribution of the density of ISE at a given point. This follows from earlier results by Bousquet-Mélou on convergence of the vertical profile at a fixed point. We also provide a recurrence relation defining the moments of the (random) moments of ISE.
Ground States through Variational Optimization using Matrix Product States: a comparison between open and periodic boundary conditions
Creators: name: Schneider, Manuel
Publisher: name: Deutsches Elektronen-Synchrotron, DESY, Hamburg
Year: 2019
Subjects: Matrix Produkt Zustände
Matrix Produkt Operatoren
Tensor Netzwerke
periodische Randbedingungen
offene Randbedingungen
transverses Ising Modell
kritisches Heisenberg Modell
Matrix Product States
Matrix Product Operators
tensor networks
periodic boundary conditions
open boundary conditions
transverse Ising model
critical Heisenberg model

description: Masterarbeit, Humboldt-Universität zu Berlin, 2019; 83 pp. (2019). doi:10.18452/23712 = Masterarbeit, Humboldt-Universität zu Berlin, 2019
description: Matrix Product States can efficiently approximate ground states. Based on the Matrix Product formalism we use variational optimization methods to calculate ground state energies of the spin-1/2 critical Heisenberg and the spin-/2 transverse Ising model in one spatial dimension. We compare open boundary conditions (obc) to periodic boundary conditions (pbc). In case of pbc we test several methods to improve the conditioning of the norm matrix arising in the generalized eigenvalue problem. We find the central gauge and pseudo inverting of the norm to be the most effective stabilization techniques. A compression of transfer matrices makes pbc competitive in runtime to obc. The energy densities with pbc converge faster in the bond dimension and are very close to the thermodynamic limit at small system sizes already. With obc, the infinite volume limit is only accurately resembled by extrapolation in the system size. At comparable runtimes this makes pbc superior to obc when it comes to studying the thermodynamic limit.
Breaking (Global) Barriers in Parallel Stochastic Optimization with Wait-Avoiding Group Averaging
Creators: name: Li, Shigang
name: Ben-Nun, Tal
name: Nadiradze, Giorgi
name: Di Girolamo, Salvatore
name: Dryden, Nikoli
name: Alistarh, Dan
name: Hoefler, Torsten
Publisher: name: arXiv
Year: 2020
Subjects: subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences
subject: C.1.4; D.1.3; I.2

description: Deep learning at scale is dominated by communication time. Distributing samples across nodes usually yields the best performance, but poses scaling challenges due to global information dissemination and load imbalance across uneven sample lengths. State-of-the-art decentralized optimizers mitigate the problem, but require more iterations to achieve the same accuracy as their globally-communicating counterparts. We present Wait-Avoiding Group Model Averaging (WAGMA) SGD, a wait-avoiding stochastic optimizer that reduces global communication via subgroup weight exchange. The key insight is a combination of algorithmic changes to the averaging scheme and the use of a group allreduce operation. We prove the convergence of WAGMA-SGD, and empirically show that it retains convergence rates similar to Allreduce-SGD. For evaluation, we train ResNet-50 on ImageNet; Transformer for machine translation; and deep reinforcement learning for navigation at scale. Compared with state-of-the-art decentralized SGD variants, WAGMA-SGD significantly improves training throughput (e.g., 2.1x on 1,024 GPUs for reinforcement learning), and achieves the fastest time-to-solution (e.g., the highest score using the shortest training time for Transformer).
description: Published in IEEE Transactions on Parallel and Distributed Systems (IEEE TPDS), vol. 32, no. 7, pp. 1725-1739, 1 July 2021
Influence of the neutron star 1E 161348-5055 in RCW 103 on the surrounding medium
Creators: name: Reynoso, E. M.
name: Green, A. J.
name: Johnston, S.
name: Goss, W. M.
name: Dubner, G. M.
name: Giacani, E. B.
Publisher: name: arXiv
Year: 2003
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We have carried out a study of the neutral hydrogen in the direction of the X-ray source 1E 161348-5055, a compact central object (CCO) located in the interior of the supernova remnant (SNR) RCW 103. The HI 21 cm line observations were carried out using the Australia Telescope Compact Array, complemented with single dish data from the Parkes radio telescope to recover information at all spatial scales. We derive a distance to RCW 103 of 3.3 kpc, in agreement with previous distance measurements. We have also detected a small hole in the HI emission which is positionally and kinematically coincident with the location of the CCO which confirms the association between the SNR and the CCO. This is the third case of a depression in HI emission seemingly associated with CCOs in SNRs. The characteristic parameters of the holes such as their size, eccentricity and evacuated mass are similar in all three cases. We estimate the absorbing HI column density towards 1E 161348-5055 to be ~6 x 10^{21} cm^{-2}, a value compatible with a blackbody solution for the CCO X-ray emission. However, the implied brightness temperature is very high comparedto most neutron stars. Moreover, the strong long-term variability in X-rays favours the hypothesis that 1E 161348-5055 is an accreting binary sourcerather than an isolated, cooling neutron star. An analysis of the continuum image obtained at 1.4 GHz from these observations shows no trace of a pulsar wind nebula around 1E 161348-5055, in spite of it being a young object.
description: 12 pages, 4 gif figures, to appear in Publications of the Astronomical Society of Australia (PASA). Full postscript version with all 4 figures is available at http://www.physics.usyd.edu.au/~simonj/rcw103.ps.gz
Fungal and Bacterial Diversity Patterns of Two Diversity Levels Retrieved From a Late Decaying Fagus sylvatica Under Two Temperature Regimes
Creators: name: Muszynski, Sarah
name: Maurer, Florian
name: Henjes, Sina
name: Horn, Marcus A.
name: Noll, Matthias
Publisher: name: Lausanne : Frontiers Media
Year: 2021
Subjects: subject: bacterial and fungal community composition
subject: dead wood decomposition
subject: Fagus Sylvatica
subject: fluctuating temperature regime
subject: insurance hypothesis
subject: microbial network analysis
subject: Dewey Decimal Classification::500 | Naturwissenschaften::570 | Biowissenschaften, Biologie

description: Environmental fluctuations are a common occurrence in an ecosystem, which have an impact on organismic diversity and associated ecosystem services. The aim of this study was to investigate how a natural and a species richness-reduced wood decaying community diversity were capable of decomposing Fagus sylvatica dead wood under a constant and a fluctuating temperature regime. Therefore, microcosms with both diversity levels (natural and species richness-reduced) were prepared and incubated for 8 weeks under both temperature regimes. Relative wood mass loss, wood pH, carbon dioxide, and methane emissions, as well as fungal and bacterial community compositions in terms of Simpson‘s diversity, richness and evenness were investigated. Community interaction patterns and co-occurrence networks were calculated. Community composition was affected by temperature regime and natural diversity caused significantly higher mass loss than richness-reduced diversity. In contrast, richness-reduced diversity increased wood pH. The bacterial community composition was less affected by richness reduction and temperature regimes than the fungal community composition. Microbial interaction patterns showed more mutual exclusions in richness-reduced compared to natural diversity as the reduction mainly reduced abundant fungal species and disintegrated previous interaction patterns. Microbial communities reassembled in richness-reduced diversity with a focus on nitrate reducing and dinitrogen-fixing bacteria as connectors in the network, indicating their high relevance to reestablish ecosystem functions. Therefore, a stochastic richness reduction was followed by functional trait based reassembly to recover previous ecosystem productivity. © Copyright © 2021 Muszynski, Maurer, Henjes, Horn and Noll.
title: An evaluation of domestic food hygiene and food preparation practices
Creators: name: Worsfold, Denise
Publisher: name: The Open University
Year: 1994

description: The aim of this investigation was to evaluate the hygiene of domestic food preparation practices. The traditional survey approach used to study this behaviour has problems of interpretation and verification. In this study direct observation, supplemented with food temperature measurements was used to gather information for the purpose of developing an understanding of the causes of domestic food poisoning. The food handling practices of 108 people preparing foods commonly implicated in outbreaks of food poisoning were analysed. A HACCP approach was employed and a standard measure of hygienic food handling behaviour, the Food Safety Risk Score, (FSR) was devised. The FSR score indicated the extent of the use of appropriate control measures during food preparation. The higher the score the greater the risk of unsafe food being produced. Scores expressed as a percentage, ranged from 0 to 65% with over half of the subjects scoring below 20%. More than half (60%) of the people cooked in advance of consumption but most (85%) cooked the food thoroughly. Few used any method to speed the cooling of cooked food. Temperature abuse during food transport and storage was exhibited by more than 40% of people. Cooked food was held at ambient temperature for prolonged periods by 19% of the people and was re-heated inadequately by 11%. The standard of personal hygiene of some participants was low. An assessment of the cleanliness of the domestic kitchen and the condition of equipment and surfaces used in food preparation, based on ATP measurements and a kitchen checklist showed that there was a wide variation in the standards found in homes. The great potential for indirect and direct cross contamination in the domestic kitchen was highlighted. The problems involved in persuading people to practise well-known food hygiene principles are considered and recommendations for improving domestic food hygiene are made.
Search for class II methanol masers at 23.1 GHz
Creators: name: Cragg, D. M.
name: Sobolev, A. M.
name: Caswell, J. L.
name: Ellingsen, S. P.
name: Godfrey, P. D.
Publisher: name: arXiv
Year: 2004
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: In the early days of methanol maser discoveries the 9(2)-10(1) A+ transition at 23.1 GHz was found to exhibit maser characteristics in the northern star-forming region W3(OH), and probable maser emission in two other sources. Attention subsequently turned to the 6.6-GHz 5(1)-6(0) A+ methanol maser transition, which has proved a valuable tracer of early high-mass star formation. We have undertaken a new search for 23.1-GHz methanol masers in 50 southern star formation regions using the Parkes radiotelescope. The target sources all exhibit class II methanol maser emission at 6.6 GHz, with 20 sources also displaying maser features in the 107.0-GHz 3(1)-4(0) A+ methanol line. Strong emission at 23.1 GHz in NGC 6334F was confirmed, but no emission was detected in the remaining sources. Thus the 23.1-GHz methanol masers are rare. A maser model in which methanol molecules are pumped to the second torsionally excited state by radiation from warm dust can account for class II maser activity in all the transitions in which it is observed. According to this model the 23.1-GHz maser is favoured by conditions representing low gas temperature, high external dust temperature, low gas density, and high column density of methanol; the scarcity of this maser indicates that such combinations of conditions are uncommon. We have undertaken new model calculations to examine the range of parameters compatible with the upper limits on 23.1-GHz emission from our survey.
description: 11 pages, 6 figures, accepted for publication in MNRAS, Latex, mn2e.cls
Associative nitrogen fixation in nodules of the conifer Lepidothamnus fonkii (Podocarpaceae) inhabiting ombrotrophic bogs in southern Patagonia
Creators: name: Borken, Werner
name: Horn, Marcus A.
name: Geimer, Stefan
name: Aguilar, Nelson A. Bahamonde
name: Knorr, Klaus-Holger
Publisher: name: London : Nature Publishing Group
Year: 2016
Subjects: subject: acetylene-reduction assay
subject: root-nodules
subject: diversity
subject: soil
subject: patterns
subject: bacteria
subject: culture
subject: wetland
subject: foliar
subject: growth
subject: Dewey Decimal Classification::500 | Naturwissenschaften

description: Biological N2 fixation (BNF) in the rhizosphere of Podocarpaceae is currently attributed to unspecific diazotrophs with negligible impact on N acquisition. Here, we report specific and high associative BNF in dead cells of root nodules of Lepidothamnus fonkii distributed in ombrotrophic peatlands of Patagonia. BNF of nodulated roots, intact plants of L. fonkii and rhizospheric peat was assessed by 15N2 and acetylene reduction. Diazotrophs were identified by electron microscopy, analysis of nitrogenase encoding genes (nifH) and transcripts, and 16S rRNA. Nitrogenase encoding nifH transcripts from root nodules point to Beijerinckiaceae (Rhizobiales), known as free-living diazotrophs. Electron microscopy and 16S rRNA analysis likewise identified active Beijerinckiaceae in outer dead cells of root nodules. NifH transcripts from the rhizopshere peat revealed diverse active diazotrophs including Beijerinckiaceae. Both methods revealed high activity of nitrogenase rates in cut roots of L. fonkii (2.5 μmol N g−1 d.w. d−1 based on 15N2 assay; 2.4 μmol C2H4 g−1 d.w. d−1 based on acetylene reduction assay). The data suggest that (i) nodules recruit diazotrophic Beijerinckiaceae from peat, (ii) dead nodule cells provide an exclusive habitat for Beijerinckiaceae, and (iii) BNF in L. fonkii is one potent pathway to overcome N deficiency in ombrotrophic peatlands of Patagonia.
Frequency domain analysis of the ultrawideband radiowave propagation channel
Creators: name: Xin, Ni
Publisher: name: University of British Columbia
Year: 2011

description: The CM 1-8 channel impulse response (CIR) models developed by the IEEE 802.15Aa task group are widely used to fairly compare the performance of alternative UWB signaling schemes under representative line-of-sight and non-line-of-sight conditions in four different environments: residential, office, industrial and outdoor. However, with the advent of MB-OFDM and related schemes, channel frequency response (CFR) models are becoming more pertinent. Here, we show how statistical models of the autoregressive frequency domain (AR-FD) model parameters that estimate for CM 1-8 can be used to gain insights concerning the nature of the channels and efficiently simulate the frequency response of the channels. After generating several thousand instances of the channel response, estimating the AR-FD model parameters for each one, then applying the Akaike Information Criterion (AIC) to determine the appropriate model order, we determine the marginal distributions that best describe each of the AR-FD parameters and their mutual correlation for each of the eight scenarios. We find that the model parameters fall into two independent groups: (1) a set of initial condition parameters that are jointly Gaussian and therefore completely described by their means, variances, and mutual correlation coefficients and (2) a set of parameters that describe the amplitude and phase of the autoregressive poles and the variance of the driving noise and that are described by more exotic distributions. As a result, their mutual correlation is most conveniently described by a copula, a statistical method widely used in finance and finding increasing use in engineering. The result allows us to specify both: (1) a set of statistical parameters that define frequency domain versions of CM 1-8 and (2) a frequency domain channel response simulator. Comparison of the distribution of RMS delay spreads associated with the original training data and simulated channel responses shows good agreement. Further, we demonstrate the utility of the AR-FD approach by using it to interpret UWB channel response data collected within an aircraft passenger cabin and by using AR-FD model parameters as features in the comparison and classification of UWB channel responses collected in different environments.
title: Applications of numerical analysis in navigation
Creators: name: Williams, Roy
Publisher: name: The Open University
Year: 1994

description: Part one of the thesis contains analysis of the methods of computation in navigation. We start with loxodromic navigation and, although this subject is well documented, we make a positive attempt to analyse the subject matter using the methods of differential geometry. We then turn to the problem of shortest path curves and set out an alternative method of solving the problem of navigating along the arc of a great circle on the surface of a sphere which can be generalised to other surfaces. In particular, a contribution made by the thesis is an analysis of the problem of navigating along shortest path geodesic arcs on the surface of a spheroid which introduces an algebraic representation of the geodesic curve by solving Clairaut' s equation using a cylindrical transformation. We are therefore able to compute the the coordinates of the positions of points along the path of the geodesic and the length of arc along the path of the. geodesic curve can then be computed step by step between these points by a numerical method - the Direct Cubic Spline method which was first introduced by this author in the Bachelor of Philosophy thesis in 1982 and is developed further in part 2 of this thesis. We apply this method also to the special problem of computing the distance along the shortest path between nearly antipodean points on the surface of a spheroid. We analyse the problem of computing an observer's position on the surface of the Earth using astronomical observations and show how a position locus is distorted when it is transferred over the surface. We offer a method of computing the observer's position by a series of observations of a single astronomical body taken over a comparitively short period of time and which does not necessarily include an observation at the tide of meridian passage of the body. In part two of the thesis we discuss the Direct Spline approximation to integrals and give some error bounds. The Direct Cubic Spline is a step by step method of fitting a cubic spline to the integral of a function directly which computes the value of the integral of the function step by step between the data points which need not be evenly spaced. We extend the idea to splines of higher order and give the formula from which they may be obtained but we show that, except for a particular special form of the direct quartic spline. the higher order direct splines do not yield algorithm for computing integrals which are as efficient as the Direct Cubic Spline.
title: Gender, caring and learning disability
Creators: name: Walmsley, Janette Susan
Publisher: name: The Open University
Year: 1995

description: The thesis explores the meaning of caring in the lives of a group of people who are labelled as dependants, adults with learning difficulties. Through biographical interviews and documentary research the author examines how care for people with learning difficulties has developed over time in one local area; and the understandings people on the receiving end have of the care offered them by families and staff. The findings suggest that dependency is not acknowledged by the majority of people interviewed who present themselves as givers of care as much as recipients of care. The research identifies gender as an important variable in the way care and caring are understood and experienced. The research makes a contribution to the literatures on gender and caring; family; peer and staff relationships of adults with learning difficulties; the history of learning disability; and qualitative research with marginalised groups.
Lattice-preferred orientations of late-Variscan granitoids derived from neutron diffraction data: implications for magma emplacement mechanisms
Creators: name: Müller, Axel
name: Leiss, Bernd
name: Ullemeyer, Klaus
name: Breiter, Karel
Publisher: name: Springer-Verlag
Year: 2010

description: The lattice-preferred orientation (LPOs) of two late-Variscan granitoids, the Meissen monzonite and the Podlesí dyke granite, were determined from high-resolution time-of-flight neutron diffraction patterns gained at the diffractometer SKAT in Dubna, Russia. The results demonstrate that the method is suitable for the LPO analysis of polyphase, relatively coarse-grained (0.1–6 mm) rocks. The Meissen monzonite has a prominent shape-preferred orientation (SPO) of the non-equidimensional minerals feldspar, mica and amphibole, whereas SPO of the Podlesí granite is unapparent at the hand-specimen scale. The neutron diffraction data revealed distinct LPOs in both granitoids. The LPO of the non-equidimensional minerals feldspar, mica and amphibole developed mainly during magmatic flow. In the case of the Meissen monzonite, the magmatic flow was superimposed by regional shear tectonics, which, however, had no significant effect on the LPOs. In both samples, quartz shows a weak but distinct LPO, which is atypical for plastic deformation and different in the syn-kinematic Meissen monzonite and the post-kinematic Podlesí granite. We suggest that, first of all, the quartz LPO of the Meissen monzonite is the result of oriented growth in an anisotropic stress field. The quartz LPO of the Podlesí granite, which more or less resembles a deformational LPO in the flattening field of the local strain field, developed during magmatic flow, whereby the rhombohedral faces of the quartz crystals adhered to the (010) faces of aligned albite and to the (001) faces of zinnwaldite. Due to shape anisotropy of their attachments, the quartz crystals were passively aligned by magmatic flow. Thus, magmatic flow and oriented crystal growth are the major LPO-forming processes in both granitoids. For the Meissen monzonite, the solid-state flow was too weak to cause significant crystallographic re-orientation of the minerals aligned by magmatic flow. Finally, the significance of our results for the evaluation of the regional tectonic environment during magma emplacement is discussed. The discussion on the regional implications of the more methodologically oriented results provides the basis for future, more regionally aimed studies in view of the fabric characteristics of such plutons and their developing mechanisms.
Emissions and health risks from the use of 3D printers in an occupational setting
Creators: name: Chan, Felix L
name: Chun-Yip Hon
name: Tarlo, Susan M
name: Rajaram, Nikhil
name: House, Ronald
Publisher: name: Taylor & Francis
Year: 2020
Subjects: subject: Biophysics
subject: Biochemistry
subject: Pharmacology
subject: Biotechnology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: FOS: Biological sciences
subject: Cancer
subject: Science Policy

description: The aim of this study was to determine concentrations of particulates and volatile organic compounds (VOCs) emitted from 3D printers using polylactic acid (PLA) filaments at a university workroom to assess exposure and health risks in an occupational setting. Under typical-case (one printer) and worst-case (three printers operating simultaneously) scenarios, particulate concentration (total and respirable), VOCs and formaldehyde were measured. Air samples were collected in the printing room and adjacent hallway. Size-resolved levels of nano-diameter particles were also collected in the printing room. Total particulate levels were higher in the worst-case scenario (0.7 mg/m3) vs. typical-case scenario (0.3 mg/m3). Respirable particulate and formaldehyde concentrations were similar between the two scenarios. Size-resolved measurements showed that most particles ranged from approximately 27 to 116 nm. Total VOC levels were approximately 6-fold higher during the worst-case scenario vs. typical situation with isopropyl alcohol being the predominant VOC. Airborne concentrations in the hallway were generally lower than inside the printing room. All measurements were below their respective occupational exposure limits. In summary, emissions of particulates and VOCs increased when multiple 3D printers were operating simultaneously. Airborne levels in the adjacent hallway were similar between the two scenarios. Overall, data suggest a low risk of significant and persistent adverse health effects. Nevertheless, the health effects attributed to 3D printing are not fully known and adherence to good hygiene principles is recommended during use of this technology.
Effective Actions of Matrix Models on Homogeneous Spaces
Creators: name: Imai, T.
name: Kitazawa, Y.
name: Takayama, Y.
name: Tomino, D.
Publisher: name: arXiv
Year: 2003
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We evaluate the effective actions of supersymmetric matrix models on fuzzy S^2\times S^2 up to the two loop level. Remarkably it turns out to be a consistent solution of IIB matrix model. Based on the power counting and SUSY cancellation arguments, we can identify the 't Hooft coupling and large N scaling behavior of the effective actions to all orders. In the large N limit, the quantum corrections survive except in 2 dimensional limits. They are O(N) and O(N^{4\over 3}) for 4 and 6 dimensional spaces respectively. We argue that quantum effects single out 4 dimensionality among fuzzy homogeneous spaces.
description: 28 pages, 1 figure, published version in Nucl. Phys. B
AB Doradus C: Age, Spectral Type, Orbit, and Comparison to Evolutionary Models
Creators: name: Nielsen, E. L.
name: Close, L. M.
name: Guirado, J. C.
name: Biller, B. A.
name: Lenzen, R.
name: Brandner, W.
name: Hartung, M.
name: Lidman, C.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We expand upon the results of Close et al. 2005 regarding the young, low-mass object AB Dor C and its role as a calibration point for theoretical tracks. We present an improved spectral reduction and a new orbital solution with two additional epochs. Our improved analysis confirms our spectral type of M8 (+/- 1) and mass of 0.090+/-0.003 solar masses for AB Dor C. Comparing the results for AB Dor C with other young, low-mass objects with dynamical masses we find a general trend where current evolutionary models tend to over-predict the temperature (or under-predict the mass) for low mass stars and brown dwarfs. Given our precision, there is a ~99% chance that the mass of AB Dor C is underestimated by the DUSTY tracks in the HR diagram.
description: 7 pages, 10 figures, proceedings for the workshop "Ultralow-mass star formation and evolution", to be published in Astronomische Nachrichten - Astronomical Notes
Supplementary file 3 from Costs of molecular adaptation to the chemical exposome: a focus on xenobiotic metabolism pathways
Creators: name: Tomkiewicz, Céline
name: Coumoul, Xavier
name: Nioche, Pierre
name: Barouki, Robert
name: Blanc, Etienne B.
Publisher: name: The Royal Society
Year: 2024
Subjects: classificationCode: 310199
subject: Biochemistry and cell biology not elsewhere classified
classificationCode: 310803
subject: Plant cell and molecular biology
classificationCode: 310902
subject: Animal cell and molecular biology

description: Organisms adapt to their environment through different pathways. In vertebrates, xenobiotics are detected, metabolized and eliminated through the inducible xenobiotic-metabolizing pathways (XMP) which can also generate reactive toxic intermediates. In this review, we will discuss the impacts of the chemical exposome complexity on the balance between detoxication and side effects. There is a large discrepancy between the limited number of proteins involved in these pathways (few dozens) and the diversity and complexity of the chemical exposome (tens of thousands of chemicals). Several XMP proteins have a low specificity which allows them to bind and/or metabolize a large number of chemicals. This leads to undesired consequences, such as cross-inhibition, inefficient metabolism, release of toxic intermediates, etc. Furthermore, several XMP proteins have endogenous functions that may be disrupted upon exposure to exogenous chemicals. The gut microbiome produces a very large number of metabolites that enter the body and are part of the chemical exposome. It can metabolize xenobiotics and either eliminate them or lead to toxic derivatives. The complex interactions between chemicals of different origins will be illustrated by the diverse roles of the Aryl hydrocarbon receptor which binds and transduces the signals of a large number of xenobiotics, microbiome metabolites, dietary chemicals and endogenous compounds.This article is part of the theme issue ‘Endocrine responses to environmental variation: conceptual approaches and recent developments’.
Advancing Geospatial Data Analysis with XDGGS
Creators: name: Magin, Justus
name: Bovy, Benoit
name: Delouis, Jean-Marc
name: Fouilloux, Anne
name: Coca-Castro, Alejandro
name: Abernathey, Ryan
name: Strobl, Peter
name: Kmoch, Alexander
name: Odaka, Tina Erica
Publisher: name: Zenodo
Year: 2024

description: The Pangeo community is developing xdggs. This poster was presented during the 3rd Destination Earth User eXchange in Darmstadt (15 October 2024):

XDGGS is an Xarray extension developed through a sprint at the ESA BiDS’23 conference, led by the Pangeo community in collaboration with OSGeo and the OGC. 

The OGC DGGS SWG works on standardizing concepts and definitions around DGGS. The cooperation ensures reference systems and grids are usable across libraries and APIs.

XDGGS provides a unified, high-level API that simplifies the use of DGGS types like HEALPIX, H3, or DGGRID ISEA7H, using DGGS-specific cell identifiers as an index within Xarray.

By integrating DGGS with Xarray, XDGGS enables efficient geospatial workflows, reducing complexity and enhancing Xarray's data processing capabilities.

This extension promotes FAIR data practices, improving data access and interoperability for large-scale geospatial applications.
Non-Coherent and Backscatter Communications: Enabling Ultra-Massive Connectivity in 6G Wireless Networks
Creators: name: Nawaz, Syed Junaid
name: Sharma, Shree Krishna
name: Mansoor, Babar
name: Patwary, Mohmammad N.
name: Khan, Noor M.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Signal Processing (eess.SP)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: With the commencement of the 5G of wireless networks, researchers around the globe have started paying their attention to the imminent challenges that may emerge in the beyond 5G (B5G) era. Various revolutionary technologies and innovative services are offered in 5G networks, which, along with many principal advantages, are anticipated to bring a boom in the number of connected wireless devices and the types of use-cases that may cause the scarcity of network resources. These challenges partly emerged with the advent of massive machine-type communications (mMTC) services, require extensive research innovations to sustain the evolution towards enhanced-mMTC (e-mMTC) with the scalable network cost in 6\textsuperscript{th} generation (6G) wireless networks. Towards delivering the anticipated massive connectivity requirements with optimal energy and spectral efficiency besides low hardware cost, this paper presents an enabling framework for 6G networks, which utilizes two emerging technologies, namely, non-coherent communications and backscatter communications (BsC). Recognizing the coherence between these technologies for their joint potential of delivering e-mMTC services in the B5G era, a comprehensive review of their state-of-the-art is conducted. The joint scope of non-coherent and BsC with other emerging 6G technologies is also identified, where the reviewed technologies include unmanned aerial vehicles (UAVs)-assisted communications, visible light communications (VLC), quantum-assisted communications, reconfigurable large intelligent surfaces (RLIS), non-orthogonal multiple access (NOMA), and machine learning-aided intelligent networks. Subsequently, the scope of these enabling technologies for different device types, service types, and optimization parameters is analyzed...
description: 6G Wireless Networks, Preprint, 34 pages, 11 Figures
Sub-Doppler Cooling and Compressed Trapping of YO Molecules at $μ$K Temperatures
Creators: name: Ding, Shiqian
name: Wu, Yewei
name: Finneran, Ian A.
name: Burau, Justin J.
name: Ye, Jun
Publisher: name: arXiv
Year: 2020
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: Complex molecular structure demands customized solutions to laser cooling by extending its general set of principles and practices. Yttrium monoxide (YO) has unique intramolecular interactions. The Fermi-contact interaction dominates over the spin-rotation coupling, resulting in two manifolds of closely spaced states, with one of them possessing a negligible Landé g-factor. This unique energy level structure favors dual-frequency DC magneto-optical trapping (MOT) and gray molasses cooling (GMC). We report exceptionally robust cooling of YO at 4 $μ$K over a wide range of laser intensity, detunings (one and two-photon), and magnetic field. The magnetic insensitivity enables the spatial compression of the molecular cloud by alternating GMC and MOT under the continuous operation of the quadrupole magnetic field. A combination of these techniques produces a laser-cooled molecular sample with the highest phase space density in free space.
description: 9 pages, 6 figures
Uniform 1-Cochains and Genuine Laminations
Creators: name: Coskunuzer, Baris
Publisher: name: arXiv
Year: 2003
Subjects: subject: Geometric Topology (math.GT)
subject: FOS: Mathematics
subject: 57M50

description: We construct a pair of transverse genuine laminations on an atoroidal 3-manifold admitting transversely orientable uniform 1-cochain. The laminations are induced by the uniform 1-cochain and they are indeed the "straightening" of the coarse laminations defined in [Ca], by using minimal surface techniques. Moreover, when you collapse these laminations, you can get a topological pseudo-Anosov flow, as defined by Mosher, [Mo].
description: 34 pages, 17 figures, V2: minor changes in concluding remarks
Turbulence and Fossil Turbulence in Oceans and Lakes
Creators: name: Leung, Pak Tao
name: Gibson, Carl H.
Publisher: name: arXiv
Year: 2003
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Turbulence is defined as an eddy-like state of fluid motion where the inertial-vortex forces of the eddies are larger than any of the other forces that tend to damp the eddies out. Energy cascades of irrotational flows from large scales to small are non-turbulent, even if they supply energy to turbulence. Turbulent flows are rotational and cascade from small scales to large, with feedback. Viscous forces limit the smallest turbulent eddy size to the Kolmogorov scale. In stratified fluids, buoyancy forces limit large vertical overturns to the Ozmidov scale and convert the largest turbulent eddies into a unique class of saturated, non-propagating, internal waves, termed fossil-vorticity-turbulence. These waves have the same energy but different properties and spectral forms than the original turbulence patch. The Gibson (1980, 1986) theory of fossil turbulence applies universal similarity theories of turbulence and turbulent mixing to the vertical evolution of an isolated patch of turbulence in a stratified fluid as its growth is constrained and fossilized by buoyancy forces. These theories apply to the dynamics of atmospheric, astrophysical and cosmological turbulence.
description: 31 pages, 11 figures, 2 tables, see http://www-acs.ucsd.edu/~ir118 Accepted for publication by the Chinese Journal of Oceanology and Limnology