cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
The Shapes of AGB Envelopes as Probes of Binary Companions
Creators: name: Huggins, P. J.
name: Mauron, N.
name: Wirth, E. A.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We describe how the large scale geometry of the circumstellar envelopes of asymptotic giant branch stars can be used to probe the presence of unseen stellar companions. A nearby companion modifies the mass loss by gravitationally focusing the wind towards the orbital plane, and thereby determines the shape of the envelope at large distances from the star. Using available simulations, we develop a prescription for the observed shapes of envelopes in terms of the binary parameters, envelope orientation, and type of observation. The prescription provides a tool for the analysis of envelope images at optical, infrared, and millimetre wavelengths, which can be used to constrain the presence of companions in well observed cases. We illustrate this approach by examining the possible role of binary companions in triggering the onset of axi-symmetry in planetary nebula formation. If interaction with the primary leads to axi-symmetry, the spherical halos widely seen around newly formed nebulae set limits on the companion mass. Only low mass objects may orbit close to the primary without observable shaping effects: they remain invisible until the interaction causes a sudden change in the mass loss geometry.
description: 11 pages, 7 figures, to appear in MNRAS
On the Possible Observation of Mirror Matter
Creators: name: Ibrahim, Tarek
name: Nath, Pran
Publisher: name: arXiv
Year: 2009
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The possibility that mirror matter with masses in the several hundred GeV- TeV range exists is explored. Mirror matter appears quite naturally in many unified models of particle interactions both in GUTs and in strings often in vector-like combinations. Some of these vector-like multiplets could escape acquiring super heavy masses and remain light down to the low energies where they acquire vector-like masses of electroweak size. It is found that a very small mixing of the vector-like multiplets with MSSM matter (specifically with the third generation matter) can produce very large contributions to the magnetic moment of the $τ$ neutrino by as much as several orders of magnitude putting this moment in the range of accessibility of improved experiment. Further, it is shown that if mirror matter exists it would lead to distinctive signatures at colliders and thus such matter can be explored at the LHC energies with available luminosities.
description: 8 pages, 1 figure. Based on talk at the International Workshop on "Beyond the Standard Model Physics and LHC Signatures (BSM-LHC)," Northeastern University, 2-4 June, 2009 to appear in BSM-LHC proceedings, NPB(Suppl)
The response of muon detectors to the primary cosmic ray flux
Creators: name: Cooke, David James
Publisher: name: University Of Tasmania
Year: 2023

description: This thesis presents the results of some investigations into problems associated with the determination of the relationship between the sea level directional muon flux, as observed by muon detectors, and the primary cosmic ray flux. Previous estimates of muon coupling coefficients (which express the primary-secondary intensity relationship) have been in poor agreement, and insufficient to define the zenith angle dependence of the coefficients. A new determination was therefore undertaken.
K-meson vector and tensor decay constants and BK-parameter from Nf=2 tmQCD
Creators: name: Dimopoulos, P.
name: Frezzotti, R.
name: Gimenez, V.
name: Lubicz, V.
name: Mescia, F.
name: Rossi, G. C.
name: Simula, S.
name: Vladikas, A.
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: FOS: Physical sciences

description: We present work in progress on the computation of the K-meson vector and tensor decay constants, as well as the B-parameter in Kaon oscillations. Our simulations are performed in a partially quenched setup, with two dynamical (sea) Wilson quark flavours, having a maximally twisted mass term. Valence quarks are either of the standard or the Osterwalder-Seiler maximally twisted variety. These two regularizations can be suitably combined in order to obtain a BK parameter which is both multiplicatively renormalizable and O(a) improved.
description: 7 pages, 4 figures, talk presented at the XXVI International Symposium on Lattice Field Theory, July 14 - 19, 2008, Williamsburg, Virginia, USA
Optimising the configuration of food supply chains
Creators: name: Li, Haitao
name: Li, De
name: Jiang, Dali
Publisher: name: Taylor & Francis
Year: 2020
Subjects: subject: Medicine
subject: Ecology
subject: FOS: Biological sciences
subject: Sociology
subject: FOS: Sociology
subject: Biological Sciences not elsewhere classified
subject: Science Policy

description: We study the food supply chain configuration problem (FSCCP) to optimise the tactical-level mode selection and inventory positioning decisions for a general multi-echelon food supply chain. A mixed-integer nonlinear programming (MINLP) model is developed for the FSCCP, with new building blocks to address the perishability issue in terms of both food loss and quality deterioration. Our model minimises the system-wide total supply chain costs and balances multiple supply chain performance metrics: cost, time and quality. Computational studies show that the optimal FSCCP solutions significantly outperform two heuristic solutions that focus solely on cost or quality. Additional insights are obtained on the impacts of key input parameters on the optimal configuration and performance metrics.
In search of the QCD-Gravity correspondence
Creators: name: Brasoveanu, Theodor
name: Kharzeev, Dmitri
name: Martinez, Mauricio
Publisher: name: arXiv
Year: 2009
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Quantum Chromodynamics (QCD) is the fundamental theory of strong interactions. It describes the behavior of quarks and gluons which are the smallest known constituents of nuclear matter. The difficulties in solving the theory at low energies in the strongly interacting, non-perturbative regime have left unanswered many important questions in QCD, such as the nature of confinement or the mechanism of hadronization. In these lectures oriented towards the students we introduce two classes of dualities that attempt to reproduce many of the features of QCD, while making the treatment at strong coupling more tractable: (1) the AdS/CFT correspondence between a specific class of string theories and a conformal field theory and (2) an effective low-energy theory of QCD dual to classical QCD on a curved conformal gravitational background. The hope is that by applying these dualities to the evaluation of various properties of the strongly-interacting matter produced in heavy ion collisions one can understand how QCD behaves at strong coupling. We give an outline of the applications, with emphasis on two transport coefficients of QCD matter -- shear and bulk viscosities.
description: 31 pages, 7 figures; Lectures delivered by D. Kharzeev at the International QGP Winter School, Jaipur, India, February 1-3, 2008
The self-picture of some children in educational transition
Creators: name: Cooper, Daphne Daisy
Publisher: name: University Of Tasmania
Year: 2023

description: This study attempts to derive, describe, and compare some aspects of the cognised and the ideal self-pictures of some children in their last year of primary end first year of secondary school. Three measures - a Check List, Rogers' Test of Personality Adjustment, and the Michigan Picture Story Test - considered to differ clearly In the degree of their directness of approach, were used to obtain data about their self-pictures from 34 boys and 36 girls fulfilling certain criteria of selection. The data are analysed in relation to variables such as sex and educational level. The findings are discussed in relation primarily to personal adequacy, social attitudes and adequacy,, and interpersonal relationships. Differences in problem areas, attitudes to authority and peers, and between the pictures of the ideal self, the cognised self and the \projected\" self were found associated with variables such as sex intelligence school and educational level. The findings of this study are juxtaposed with those of similar or relevant studies."
Some physical properties of strawberries related to design of a selective harvester
Creators: name: Mehra, Harsh Kumar
Publisher: name: University of British Columbia
Year: 2011

description: A fruit selection tool, which could be used as a component of a selective strawberry harvesting system, was designed and tested. Design was based upon physical and rheological properties of the Northwest variety of strawberries which is commonly grown in British Columbia. Fruit retention force was measured as a function of time over the harvest season. Three rheological parameters, linear limit, bioyield point and tangent modulus, were calculated from force-deformation curves obtained from flat plate loading tests. These parameters were used to evaluate fruit quality and its variation over the harvest season. Correlations among quality parameters, fruit retention force, and fruit surface colour indicated that colour could be used as an accurate indicator of fruit quality and fruit maturity. Fruit surface colour was, therefore, used as the selection parameter controlling the fruit selection tool. Subjective and objective colour measurements were made. Relative reflectance curves for strawberry surface were obtained from a Unicam automatic recording spectrophotometer by scanning a 2.54 cm. diameter surface of the fruit at fast speed. Spectrum variables obtained from the reflectance curves were used for objective colour evaluation and maturity assessment. The relative reflectances at various wavelengths had good correlation with surface colour, the highest being that between reflectance at 525 nanometers and percent surface red colour. Maturity ratio for strawberries was calculated from reflectance curves and was established as the ratio of reflectances at 650 nm to 525 nm. Maturity ratio best represented the surface colour and was used to define fruit ripeness. An electronic system was designed and used to measure maturity ratio and to identify fruit maturity. Tests conducted on this system in the laboratory indicated a minimum response time of 0.166 seconds per fruit. The influence of illumination and its geometry were also investigated
Causes and Effects of Delay in Ethiopia’s Public Construction Projects: A Structural Equation Modeling Approach
Creators: name: Woldegiorgis, Bereket Haile
name: Mekonnen, Getahun Borja
name: Lemessa, Zerihun Wondimu
name: Semegn, Alehegn Melesse
Publisher: name: Poly Journal of Engineering and Technology (PJET)
Year: 2024

description: The construction industry plays a great role in the development of any country by transforming the aspirations and needs of its people into reality by implementing various physical structures. However, there are differences in its contribution depending on how well the projects are managed. One of the challenges in construction projects is delay and associated problems with project delays. Therefore, this study aimed to investigate the most significant causes and associated effects of delays in public construction projects in Ethiopia, as well as to provide overviews for potential future action. The study is limited to the causes and impacts of delays in public construction works only at randomly selected construction projects. As a result, purposive, snowball sampling techniques were applied. Structural Equation Modeling was applied to examine the relationship between 48 variables [41 factors and 7 effects], previously identified as contributing to public construction delay in the Ethiopian construction industry and their consequences. The results show that the most important element of the contractor-related factor, "shortage of materials on site," is estimated to be 3.405 according to the path analysis with IBM SPPS Amos 23. On the other hand, with a value of 3.132, external-related issues, "environmental factors," had the least impact on construction-related delays. Moreover, this study identified seven consequences of delays on public construction projects in Ethiopia, ranging from the most significant to the least significant: (1) time overrun, (2) cost overrun, (3) disagreement between the parties involved, (4) arbitration, (5) litigation and court case, (6) complete project abandonment, and (7) resource waste and underutilization.
description: Poly Journal of Engineering and Technology (PJET), Vol 2 No 2 (2024): Articles in press
An open, collaborative, and scholarly digital edition of Jirjī Niqūlā Bāz's monthly journal "al-Ḥasnāʾ" (Beirut, 1909--11): First release of volume 1
Creators: name: Grallert, Till
Publisher: name: Zenodo
Year: 2019

description: This release contains the following files

TEI files for all issues of al-Ḥasnāʾ

all volumes: basic TEI files with bibliographic information on the issue, links to facsimiles (locally and the old URLs from the British Library's Endangered Archives Programme) and a body with one  for each page linking to the digital facsimile.

volume 1: TEI files with full structural mark-up of sections and articles. Heads, bylines and other bibliographic information has been manually transcribed.

MODS and BibTeX containing bibliographic data for all issues, sections, and articles
Discovery of Very High Energy gamma-rays from the blazar S5 0716+714
Creators: name: Anderhub, H.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: The MAGIC collaboration reports the detection of the blazar S5 0716+714 z=0.31+-0.08 in very high energy gamma-rays. The observations were performed in November 2007 and in April 2008, and were triggered by the KVA telescope due to the high optical state of the object. An overall significance of the signal accounts to S =5.8sigma for 13.1 hours of data. Most of the signal S = 6.9sigma comes from the April 2008 data sample during a higher optical state of the object suggesting a possible correlation between the VHE gamma-ray and optical emissions. The differential energy spectrum of the 2008 data sample follows a power law with a photon index of Gamma = 3.45+-0.54_(stat)+-0.2_(syst), and the integral flux above 400GeV is at the level of 7.5+-2.2_(stat)+-2.3_(syst)*10^-12 cm^-2 s^-1 corresponding to a 9% Crab Nebula flux. Modeling of the broad band spectral energy distribution indicates that a structured jet model appears to be more promising in describing the available data than a simple one zone synchrotron self-Compton model.
description: accepted to ApJL
Additional file 1 of CircRNA NRIP1 promotes papillary thyroid carcinoma progression by sponging mir-195-5p and modulating the P38 MAPK and JAK/STAT pathways
Creators: name: Li, Chuang
name: Zhu, Lijuan
name: Fu, Lijun
name: Han, Mingli
name: Li, Ya
name: Meng, Zhaozhong
name: Qiu, Xinguang
Publisher: name: figshare
Year: 2021
Subjects: subject: Biophysics
subject: Biochemistry
subject: Physical Sciences not elsewhere classified
subject: Cell Biology
subject: Genetics
subject: FOS: Biological sciences
subject: Molecular Biology
subject: Chemical Sciences not elsewhere classified
subject: Biological Sciences not elsewhere classified
subject: Mathematical Sciences not elsewhere classified
subject: Developmental Biology
subject: Cancer

description: Additional file 1.
Little magazines and Canadian war poetry 1939-1945; with some reference to poetry of the first World War
Creators: name: Meis, Joanne
Publisher: name: University of British Columbia
Year: 2011

description: While English First World War poetry moved from extolling the Victorian versions of chivalric values to the "debunking" realism of some of the soldier poets, Canadian First World War poetry failed to exhibit any such development. Canadian First World War poets write a colonial interpretation of what the English inspirational war poets produced, and they did not express any disillusionment with the military-religious dogma of the war. During the Second World War, some Canadian poets produced poetry of a similar type to that which they wrote celebrating the first. But the war years saw the development of a group of young "modernist" poets who followed up the first modernist movement of the Montreal group and New Provinces, and when these poets wrote about war, the idealization of the conflict was not among their aims. Thus in Canadian war poetry the split between idealization of war and its realistic appraisal does not occur until the Second World War. The realistic appraisal of war on the part of the new poets takes many directions, but their poetry holds in common a refusal to accept any idealized version of the conflict.
Endomorphisms of O_n which preserve the canonical UHF-subalgebra
Creators: name: Conti, Roberto
name: Rordam, Mikael
name: Szymanski, Wojciech
Publisher: name: arXiv
Year: 2009
Subjects: subject: Operator Algebras (math.OA)
subject: FOS: Mathematics
subject: 46L05

description: Unital endomorphisms of the Cuntz algebra O_n which preserve the canonical UHF-subalgebra F_n of O_n are investigated. We give examples of such endomorphisms for which the associated unitary element in O_n does not belong to F_n. One such example, in the case where n=2, arises from a construction of a unital endomorphism on O_2 which preserves the canonical UHF-subalgebra and where the relative commutant of the image in O_2 contains a copy of O_2.
description: 1 figure, requires prepictex.tex, pictex.tex, postpictex.tex
An open, collaborative, and scholarly digital edition of ʿAbd Allāh Nadīm al-Idrīsī's weekly journal "al-Ustādh" (Cairo, 1892--1893): First release of all issues
Creators: name: Grallert, Till
Publisher: name: Zenodo
Year: 2019
Subjects: Digital Scholarly Edition
Arabic Press
Egypt
TEI XML
Periodical Studies

description: This release contains the following files:

TEI XML files of all issues of al-Ustādh. Files are complete with structural mark-up of mastheads, sections, articles, and with page breaks linked to digital facsimiles at http://archive.alsharekh.org.

NOTE: I have not fully validated the mostly automatically generated structural mark-up against the facsimiles.

MODS / BibTeX files with bibliographic information for all issues, sections, and articles.

For more details, see the readme.md
High Performance Quantum Computing
Creators: name: Devitt, Simon J.
name: Munro, William J.
name: Nemoto, Kae
Publisher: name: arXiv
Year: 2008
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The architecture scalability afforded by recent proposals of a large scale photonic based quantum computer, utilizing the theoretical developments of topological cluster states and the photonic chip, allows us to move on to a discussion of massively scaled Quantum Information Processing (QIP). In this letter we introduce the model for a secure and unsecured topological cluster mainframe. We consider the quantum analogue of High Performance Computing, where a dedicated server farm is utilized by many users to run algorithms and share quantum data. The scaling structure of photonics based topological cluster computing leads to an attractive future for server based QIP, where dedicated mainframes can be constructed and/or expanded to serve an increasingly hungry user base with the ideal resource for individual quantum information processing.
description: 4 Pages, 2 Figures (figures are a little low-res due to arXiv file size limits)
title: Disruptionen der Literaturwissenschaft am Beispiel der DVjs
Creators: name: Konle, Leonard
name: Jannidis, Fotis
name: Martus, Steffen
Publisher: name: Melusina Press
Year: 2021
Subjects: Fachgeschichte
Literaturwissenschaft
Topic Modeling
Simulation
Distanzmaße
Ähnlichkeit

description: Fabrikation von Erkenntnis: Experimente in den Digital Humanities -
description: Dieser Artikel beschäftigt sich mit dem Einsatz von Distanzmaßen zur Detektion disruptiver Phasen der Literaturwissenschaft anhand der Zeitschrift DVjs. In diesem Zusammenhang wird die Unmöglichkeit einer methodischen Validierung durch annotierte Daten problematisiert und ein alternativer Weg der Evaluation durch Simulation vorgeschlagen. Weitergehend wird die innere Struktur der DVjs durch den Einsatz von Topic Modeling aufgedeckt und Konsequenzen für Distanzmessung und Simulation beleuchtet.
description: This article deals with the use of distance measures to detect disruptive phases in literary studies using the Journal DVjs. In this context, the impossibility of methodological validation by annotated data is problematized and an alternative way of evaluation by simulation is proposed. Further, we analyse the internal structure of the DVjs through topic modeling and derive consequences for distance measurement and simulations.
title: COP26 must commit to eliminating deforestation
Creators: name: Ribeiro, Vivian
Publisher: name: Trase
Year: 2021
Subjects: subject: FOS: Earth and related environmental sciences
valueUri: http://www.oecd.org/science/inno/38235147.pdf
subject: FOS: Agriculture, forestry, and fisheries
valueUri: http://www.oecd.org/science/inno/38235147.pdf

description: World leaders attending the UN climate talks in Glasgow must commit to stopping commodity-driven deforestation if they are to prevent climate catastrophe.
title: ÐÐ°Ð²ÑÐºÐ¸ Ð¸ ÑÐ¼ÐµÐ½Ð¸Ñ, Ð¾ÑÐ²Ð°Ð¸Ð²Ð°ÐµÐ¼ÑÐµ ÑÑÑÐ´ÐµÐ½ÑÐ°Ð¼Ð¸ I ÐºÑÑÑÐ° Ð¸Ð½ÑÑÐ¸ÑÑÑÐ° ÑÐ½ÐµÑÐ³ÐµÑÐ¸ÐºÐ¸ Ð² Ñ Ð¾Ð´Ðµ Ð¸Ð·ÑÑÐµÐ½Ð¸Ñ Ñ Ð¸Ð¼Ð¸Ð¸
title: Skills and abilities mastered first year students of the institute of energy during the study of chemistry
Creators: name: ÐÐ¾ÑÐ°Ð³Ð¸Ð½Ð°, ÐÐ»ÐµÐ½Ð°
name: ÐÑÐ¾Ð´Ð½ÐµÐ², ÐÐ°Ð²ÐµÐ»
name: "Ð¡Ð¾Ð²ÑÐµÐ¼ÐµÐ½Ð½Ð¾Ðµ Ð¼Ð°ÑÐ¸Ð½Ð¾ÑÑÑÐ¾ÐµÐ½Ð¸Ðµ: Ð½Ð°ÑÐºÐ° Ð¸ Ð¾Ð±ÑÐ°Ð·Ð¾Ð²Ð°Ð½Ð¸Ðµ", Ð¼ÐµÐ¶Ð´ÑÐ½Ð°ÑÐ¾Ð´Ð½Ð°Ñ Ð½Ð°ÑÑÐ½Ð°Ñ ÐºÐ¾Ð½ÑÐµÑÐµÐ½ÑÐ¸Ñ (13; 2024; Ð¡Ð°Ð½ÐºÑ-ÐÐµÑÐµÑÐ±ÑÑÐ³)
Publisher: name: ÐÐÐÐÐ¢ÐÐ¥-ÐÐ ÐÐ¡Ð¡
Year: 2024
Subjects: ÐÐ°ÑÐ¸Ð½Ð¾ÑÑÑÐ¾ÐµÐ½Ð¸Ðµ
Ð¥Ð¸Ð¼Ð¸Ñ
Ð½Ð°Ð²ÑÐºÐ¸
Ð·Ð½Ð°Ð½Ð¸Ñ
ÑÐ¼ÐµÐ½Ð¸Ñ
skills
knowledge
ability

description: Ð ÑÐ°Ð±Ð¾ÑÐµ ÑÐ°ÑÑÐ¼Ð¾ÑÑÐµÐ½Ñ Ð²Ð¾Ð¿ÑÐ¾ÑÑ ÑÐ¼ÐµÐ½Ð¸Ð¹ Ð¸ Ð½Ð°Ð²ÑÐºÐ¾Ð² ÑÑÑÐ´ÐµÐ½ÑÐ¾Ð² Ð´Ð½ÐµÐ²Ð½Ð¾Ð¹ ÑÐ¾ÑÐ¼Ñ Ð¾Ð±ÑÑÐµÐ½Ð¸Ñ, Ð² ÑÐµÐ·ÑÐ»ÑÑÐ°ÑÐµ Ð¸Ð·ÑÑÐµÐ½Ð¸Ñ ÐºÑÑÑÐ° Â«Ð¥Ð¸Ð¼Ð¸ÑÂ», Ð²ÑÐ¾Ð´ÑÑÐµÐ³Ð¾ Ð² ÑÐ°Ð·Ð´ÐµÐ» ÐÐÐ. ÐÐ·ÑÑÐµÐ½Ð¸Ðµ ÐºÑÑÑÐ° Ð´Ð°ÐµÑ Ð¾ÑÐ½Ð¾Ð²Ð¾Ð¿Ð¾Ð»Ð°Ð³Ð°ÑÑÐ¸Ðµ Ð¿ÑÐµÐ´ÑÑÐ°Ð²Ð»ÐµÐ½Ð¸Ñ Ð¾ Ð¿Ð¾Ð²ÐµÐ´ÐµÐ½Ð¸Ð¸ Ð²ÐµÑÐµÑÑÐ²Ð° Ð² Ð¾ÐºÑÑÐ¶Ð°ÑÑÐµÐ¹ ÑÑÐµÐ´Ðµ. ÐÐ° Ð¾ÑÐ½Ð¾Ð²Ð°Ð½Ð¸Ð¸ ÑÑÐ¾Ð³Ð¾ Ð¾Ð±ÑÐµÐ³Ð¾ (ÑÑÐ½Ð´Ð°Ð¼ÐµÐ½ÑÐ°Ð»ÑÐ½Ð¾Ð³Ð¾) ÐºÑÑÑÐ° ÑÐ¾ÑÐ¼Ð¸ÑÑÐµÑÑÑ Ð´Ð°Ð»ÑÐ½ÐµÐ¹ÑÐµÐµ ÑÐ°Ð·Ð²Ð¸ÑÐ¸Ðµ Ñ ÑÑÑÐ´ÐµÐ½ÑÐ¾Ð² ÑÐ¼ÐµÐ½Ð¸Ð¹ Ð¿ÑÐµÐ´Ð²Ð¸Ð´ÐµÑÑ Ð¸ Ð¾ÑÑÑÐµÑÑÐ²Ð»ÑÑÑ ÑÐ°Ð·Ð»Ð¸ÑÐ½ÑÐµ ÑÐ¸Ð¼Ð¸ÑÐµÑÐºÐ¸Ðµ Ð¿ÑÐµÐ²ÑÐ°ÑÐµÐ½Ð¸Ñ, Ð° ÑÐ°ÐºÐ¶Ðµ Ð²Ð¾Ð·Ð¼Ð¾Ð¶Ð½Ð¾ÑÑÑ Ð½Ðµ Ð¿ÑÐ¾Ð²Ð¾Ð´Ñ ÑÐºÑÐ¿ÐµÑÐ¸Ð¼ÐµÐ½Ñ, Ð´ÐµÐ»Ð°ÑÑ Ð²ÑÐ²Ð¾Ð´Ñ Ð¾ Ð²Ð¾Ð·Ð¼Ð¾Ð¶Ð½Ð¾ÑÑÐ¸ Ð¸Ð»Ð¸ Ð½ÐµÐ²Ð¾Ð·Ð¼Ð¾Ð¶Ð½Ð¾ÑÑÐ¸ Ð¿ÑÐ¾ÑÐµÐºÐ°Ð½Ð¸Ñ ÑÐµÐ°ÐºÑÐ¸Ð¹.
description: The paper discusses the skills of full-time students as a result of studying the Chemistry course, which is included in the UNM section. Course study provides fundamental insights into the behavior of a substance in the environment. Based on this general (fundamental) course, further development of students' ability to foresee and carry out various chemical transformations is formed, as well as the ability not to conduct an experiment, to draw conclusions about the possibility or impossibility of reactions.
title: Missing deforestation-risk products undermine EU’s due diligence proposal
Creators: name: Bellfield, Helen
name: Pereira, Osvaldo
Publisher: name: Trase
Year: 2021
Subjects: subject: FOS: Agriculture, forestry, and fisheries
valueUri: http://www.oecd.org/science/inno/38235147.pdf
subject: FOS: Earth and related environmental sciences
valueUri: http://www.oecd.org/science/inno/38235147.pdf

description: Trase analysis of the EU’s draft due diligence regulation finds that the proposal fails to account for more than half of the bloc’s deforestation risk from imports of soy due to its exclusion of soy used in animal feed.
DIGITAL REVOLUTION IN WRITING AS AN ASSET ON  ACADEMIC GROUNDS
Creators: name: Feruza YOZILOVA, National University of Uzbekistan, PhD student in Theory and Methodology of Education (English)
name: Khilola MAKSUDOVA National University of Uzbekistan, PhD, associate professor
Publisher: name: Zenodo
Year: 2024

description: The article studies the transformative impact of digital technologies on education, including writing, emphasizing generational discrepancies in the perceptions of computers. It also contemplates on the shift from traditional writing methods to multimodal learning and how digital tools enhance engagement and comprehension. The benefits and challenges of the digital revolution are discussed as well.

Keywords: digital technologies, writing, multimodal learning, education, computers, digital learning, educational revolution.
title: Racial platform capitalism: race, labour and the making of platform infrastructures
Creators: name: Gebrial, Dalia
Publisher: name: London School of Economics and Political Science (LSE)
Year: 2025

description: The critical platform studies literature has built a compelling picture of how techniques like worker (mis)classification, algorithmic management and workforce atomisation lie at the heart of how ‘work-on-demand via apps’ actively restructure labour. Much of this emerging scholarship identifies that platform workforces are predominantly comprised of migrant and racially minoritised workers. However, few studies theorise migration and race as structuring logics of the platform model and the precarity it engenders. This thesis uses multi-sited ethnography to develop a theory of ‘racial platform capitalism’ from the standpoint of on-demand app-based workers in London. Drawing on ethnographic interviews of over 100 workers on ride-hailing platform Uber and childcare platform Bubble, this thesis makes three distinct, original contributions: 1) to the platform labour literature, it takes the passing observation that workers on gig platforms are disproportionately migrants and racial minorities, and situates this as a central analytic category of the platform economy’s emergence in urban contexts; 2) to the racial capitalism literature, it pushes for scholars to consider how processes of social differentiation operate differently through data-driven systems; 3) to the platform urbanism literature, it unpacks how, given these two observations, platforms are (re)shaping how racialised surplus populations are moving through and producing urban socio-spatial relations, by organising them into the gaps of urban and social reproductive infrastructures. Additionally, this thesis develops an innovative methodological rubric for conducting platform work ethnographies. It calls for this emerging method to be reconceptualised as an ethnographic inquiry not into ‘workplaces’, but into ‘worlds-of-work’, with multiple temporal and spatial registers.
title: Advertising on television : a comparative sociosemiological analysis
Creators: name: Giaccardi, Chiara
Publisher: name: University of Kent
Year: 2021

description: The aim of this thesis is to provide an analysis of advertising on television based on a comparative approach to textual contents and structures which attempts to identify some of the ways in which semantic, pragmatic and textual elements interact and exert mutual influence. The main focus is on the way in which advertisements activate specific fields of discourse (the semantic aspect) by engaging the viewer in an interpretive activity (the pragmatic aspect) through specific visual and aural elements (the textual aspect). Preliminary to the analysis is a brief review of some of the philosophical and socio linguistic positions on textual meaning (Part 1). Particular attention is paid to the main contributions to a pragmatically oriented textual analysis, including Halliday's concept of social semiotics, which has been especially useful for the definition of the theoretical framework for the analysis. In Part 2 the issue of the specificity of audio-visual language, as a language that combines different signifying systems (sounds, words, images, and music) is explicitly addressed: one of the aims of the research is indeed to avoid the transference of models of analysis from written or verbal to audiovisual texts, and to devise a method of analysis consistent with the specific character of the object of inquiry. Two main imperative have guided the analysis (Part 3): the need to escape both textual and social determinism, while taking into account the way in which textual elements represent and address specific social situations; and the need to consider the context of advertising discourse, in order to avoid a text-bound approach. For this reason advertisements have been approached within a comparative framework. The main characters of the two broadcasting systems have been also considered (Appendix). The data for the analysis consist of British and Italian advertisements video recorded in peak time from October 1988 to March 1989; the main focus being on car advertisements and on transnational campaigns. The other referential value of advertisements has been emphasized, with p articular regard to the repertoire of social commonplaces (or "topoi") that bear upon textual production and interpretation. The comparative framework is crucial for differentiating social conventions from what in a mere textual perspective may appear as neutral representations. The aim of this thesis is not to exhaust the argument but to develop an original a pp roach to televisual texts which is intended to complement rather than exclude other approaches.
title: ÐÐ°Ð»Ð»ÑÐ½Ð°Ñ ÑÐ¸ÑÑÐµÐ¼Ð° Ð¾ÑÐµÐ½ÐºÐ¸ Ð·Ð½Ð°Ð½Ð¸Ð¹ Ð¸ Ð¸Ð½Ð´Ð¸Ð²Ð¸Ð´ÑÐ°Ð»ÑÐ½ÑÐ¹ Ð¿Ð¾Ð´Ñ Ð¾Ð´ Ð¿ÑÐ¸ Ð¾Ð±ÑÑÐµÐ½Ð¸Ð¸ Ð²ÑÑÑÐµÐ¹ Ð¼Ð°ÑÐµÐ¼Ð°ÑÐ¸ÐºÐµ
title: Point-raiting system for assessing knowledge and individual approch to teaching higher mathematics
Creators: name: ÐÐ°Ð³ÑÐ½Ð¾Ð²Ð°, ÐÐ°ÑÐ¸Ð½Ð°
name: ÐÐ²Ð°Ð½Ð¾Ð²Ð°, ÐÑÐ±Ð¾Ð²Ñ
name: ÐÐ¶Ð¾Ð²Ð°, ÐÐ°ÑÐ°Ð»ÑÑ
name: "Ð¡Ð¾Ð²ÑÐµÐ¼ÐµÐ½Ð½Ð¾Ðµ Ð¼Ð°ÑÐ¸Ð½Ð¾ÑÑÑÐ¾ÐµÐ½Ð¸Ðµ: Ð½Ð°ÑÐºÐ° Ð¸ Ð¾Ð±ÑÐ°Ð·Ð¾Ð²Ð°Ð½Ð¸Ðµ", Ð¼ÐµÐ¶Ð´ÑÐ½Ð°ÑÐ¾Ð´Ð½Ð°Ñ Ð½Ð°ÑÑÐ½Ð°Ñ ÐºÐ¾Ð½ÑÐµÑÐµÐ½ÑÐ¸Ñ (13; 2024; Ð¡Ð°Ð½ÐºÑ-ÐÐµÑÐµÑÐ±ÑÑÐ³)
Publisher: name: ÐÐÐÐÐ¢ÐÐ¥-ÐÐ ÐÐ¡Ð¡
Year: 2024
Subjects: ÐÐ°ÑÐµÐ¼Ð°ÑÐ¸ÐºÐ°
Ð±Ð°Ð»Ð»ÑÐ½Ð°Ñ ÑÐ¸ÑÑÐµÐ¼Ð° Ð¾ÑÐµÐ½ÐºÐ¸
ÑÐ»ÐµÐºÑÑÐ¾Ð½Ð½Ð¾Ðµ Ð¾Ð±ÑÑÐµÐ½Ð¸Ðµ
Ð´Ð¸ÑÑÐ°Ð½ÑÐ¸Ð¾Ð½Ð½Ð¾Ðµ Ð¾Ð±ÑÑÐµÐ½Ð¸Ðµ
Ð¸Ð½Ð´Ð¸Ð²Ð¸Ð´ÑÐ°Ð»ÑÐ½ÑÐ¹ Ð¿Ð¾Ð´Ñ Ð¾Ð´ Ðº Ð¾Ð±ÑÑÐµÐ½Ð¸Ñ
ÑÐµÑÑ
point-rating system of assessment
e-leaning
distance learning
individual approach to teaching
test

description: Ð ÑÐ°Ð±Ð¾ÑÐµ Ð¾ÑÐ²ÐµÑÐ°ÐµÑÑÑ Ð¿ÑÐ¸Ð¼ÐµÐ½ÐµÐ½Ð¸Ðµ Ð±Ð°Ð»Ð»ÑÐ½Ð¾-ÑÐµÐ¹ÑÐ¸Ð½Ð³Ð¾Ð²Ð¾Ð¹ ÑÐ¸ÑÑÐµÐ¼Ñ Ð¿ÑÐ¸ Ð¾ÑÐµÐ½ÐºÐµ Ð·Ð½Ð°Ð½Ð¸Ð¹ ÑÑÑÐ´ÐµÐ½ÑÐ¾Ð² Ð¿Ð¾ Ð²ÑÑÑÐµÐ¹ Ð¼Ð°ÑÐµÐ¼Ð°ÑÐ¸ÐºÐµ. ÐÑÐ¾Ð¼Ðµ ÑÐ¾Ð³Ð¾, Ð¾Ð±ÑÑÐ¶Ð´Ð°ÑÑÑÑ Ð²Ð¾Ð¿ÑÐ¾ÑÑ Ð¾Ð± Ð¸Ð½Ð´Ð¸Ð²Ð¸Ð´ÑÐ°Ð»ÑÐ½Ð¾Ð¼ Ð¿Ð¾Ð´ÑÐ¾Ð´Ðµ Ðº Ð¾Ð±ÑÑÐµÐ½Ð¸Ñ Ð¼Ð°ÑÐµÐ¼Ð°ÑÐ¸ÐºÐµ, Ð° ÑÐ°ÐºÐ¶Ðµ Ð¿ÑÐ¾Ð±Ð»ÐµÐ¼Ñ Ñ ÑÑÐ°Ð½ÐµÐ½Ð¸ÐµÐ¼ Ð¸ Ð¾Ð±ÑÐ°Ð±Ð¾ÑÐºÐ¾Ð¹ ÑÐµÐ·ÑÐ»ÑÑÐ°ÑÐ¾Ð² ÑÐ°Ð±Ð¾ÑÑ Ð±Ð¾Ð»ÑÑÐ¸Ñ Ð¿Ð¾ÑÐ¾ÐºÐ¾Ð² ÑÑÑÐ´ÐµÐ½ÑÐ¾Ð², Ð¸Ð¼ÐµÑÑÐ¸Ñ Ð²Ð¾Ð·Ð¼Ð¾Ð¶Ð½Ð¾ÑÑÑ Ð¿ÑÐ¾ÑÐ²Ð¸ÑÑ ÑÐµÐ±Ñ Ð½Ð° ÑÐ°Ð·Ð½Ð¾Ð¼ ÑÑÐ¾Ð²Ð½Ðµ Ð¼Ð°ÑÐµÐ¼Ð°ÑÐ¸ÑÐµÑÐºÐ¾Ð¹ Ð¿Ð¾Ð´Ð³Ð¾ÑÐ¾Ð²ÐºÐ¸.
description: The paper highlights the use of a point-rating system in assessing studentsâ knowledge in higher mathematics. In addition, questions about an individual approach to teaching mathematics are discussed, as well as problems with storing and processing the results of large streams of students who have the opportunity to express themselves at different levels of mathematical training.
Joint universal lossy coding and identification of stationary mixing sources with general alphabets
Creators: name: Raginsky, Maxim
Publisher: name: arXiv
Year: 2009
Subjects: subject: Information Theory (cs.IT)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: We consider the problem of joint universal variable-rate lossy coding and identification for parametric classes of stationary $β$-mixing sources with general (Polish) alphabets. Compression performance is measured in terms of Lagrangians, while identification performance is measured by the variational distance between the true source and the estimated source. Provided that the sources are mixing at a sufficiently fast rate and satisfy certain smoothness and Vapnik-Chervonenkis learnability conditions, it is shown that, for bounded metric distortions, there exist universal schemes for joint lossy compression and identification whose Lagrangian redundancies converge to zero as $\sqrt{V_n \log n /n}$ as the block length $n$ tends to infinity, where $V_n$ is the Vapnik-Chervonenkis dimension of a certain class of decision regions defined by the $n$-dimensional marginal distributions of the sources; furthermore, for each $n$, the decoder can identify $n$-dimensional marginal of the active source up to a ball of radius $O(\sqrt{V_n\log n/n})$ in variational distance, eventually with probability one. The results are supplemented by several examples of parametric sources satisfying the regularity conditions.
description: 16 pages, 1 figure; accepted to IEEE Transactions on Information Theory
Tillgrallert/Digital-Muqtabas: Issue 8 Of Volume 1
Creators: name: Grallert, Till
name: Tanna, Manzi
name: Dragnev, Dimitar
name: Mayer, Klara
name: Lloyd, Daniel
name: Youssef, Layla
Publisher: name: Zenodo
Year: 2018

description: This release includes page breaks validated against the facsimile of the first edition and corresponding bibliographic metadata for issue 8 of volume 1.
Long Range Coulomb Interactions and Nanoscale Electronic Inhomogeneities in Correlated Oxides
Creators: name: Shenoy, Vijay B.
name: Gupta, Tribikram
name: Krishnamurthy, H. R.
name: Ramakrishnan, T. V.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Electronic, magnetic or structural inhomogeneities ranging in size from nanoscopic to mesoscopic scales seem endemic, and are possibly generic, to colossal magnetoresistance manganites and other transition metal oxides. We show here that an extension, to include long range Coulomb interactions, of a quantum two-fluid $\ell-b$ model proposed recently for manganites [Phys. Rev. Lett., {\bf 92}, 157203 (2004)] leads to an excellent description of such inhomogeneities. In the $\ell-b$ model two very different kinds of electronic states, one localized and polaronic ($\ell$), and the other extended or broad band ($b$) co-exist. For model parameters appropriate to manganites, and even within a simple dynamical mean-filed theory (DMFT) framework, it describes many of the unusual phenomena seen in manganites, including colossal magnetoresistance (CMR), qualitatively and quantitatively. However, in the absence of long ranged Coulomb interaction, a system described by such a model would actually phase separate, into macroscopic regions of $l$ and $b$ electrons respectively. As we show in this paper, in the presence of Coulomb interactions, the {\em macroscopic} phase separation gets suppressed, and instead nanometer scale regions of polarons interspersed with band electron puddles appear, constituting a new kind of quantum Coulomb glass. Our work points to an interplay of strong correlations, long range Coulomb interaction and dopant ion disorder as the origin of nanoscale inhomogeneities, rather than disorder frustrated phase competition as is generally believed. Based on this, we argue that the observed micrometer(meso)-scale inhomogeneities owe their existence to extrinsic causes, eg. strain due to cracks and defects. We suggest possible experiments to validate our speculation.
description: 24 Pages, 19 Figures
A chance for equality? : a Tasmanian experience of comprehensive education
Creators: name: Baker, Janice R.
Publisher: name: University Of Tasmania
Year: 2023

description: The Penguin edition of Robin Pedley's The Comprehensive School has on its cover a piper being followed by a group of dancing children. The picture brings to mind the lines of Browning's poem spoken by the lame lad left at the entrance to the hill through which his mates had passed: It's dull in our town since my playmates left, I can't forget that I'm bereft Of all the pleasant sights they see Which the piper also promised me. The promise of course was of a place where flowers were prettier, birds brighter, dogs faster and bees kinder than ever they'd been. The reader, however, suspecting malice on the piper's part, feels less sadly for the boy who has been so captivated by a promise that is probably false. The Hamelin story is mirrored in the development of comprehensive education in Tasmania. What was promised for education and its outcomes during the debates of the fifties has never been realised. This study looks at the development of comprehensive education in Tasmania. It suggests that the Tasmanian experience of comprehensive education has been marred by a systemic misinterpretation of the principle. It considers the powerful social factors which militate against the realisation of the comprehensive education principle and questions whether the influence of these factors will ever weaken enough to allow it to succeed both in educational terms and with the social promise once expected. Warrane High School, an urban four-year comprehensive High School located east of the Derwent River in southern Tasmania, is the focus of this study because it was in this school that the writer, as Vice-Principal, began to see educational failure in terms of certain social factors which seemed not to accord with the school's educational programme or with the expectations held by the community and the education system itself. The study draws on the writer's experience and observation of the Tasmanian secondary school system and on various data which particularly refer to Warrane High School. In making judgements about the various intellectual and social aspects of the school's population and in assessing its feeder community, it looks at other studies and considers their findings in the light of the expectations held for comprehensive education. In its final stages, the study examines the federal government's compensatory education programmes and then suggests directions that planning for education should take to ensure that the system of education which prevails caters fairly for all children in Tasmania.
La vision utopique dans le Telemaque de Fenelon : son importance litteraire
Creators: name: Morel, Armand G.
Publisher: name: University of British Columbia
Year: 2011

description: L'oeuvre étudiée est Les Aventures de Télémaque 1695 par François de Salignac de la Mothe-Fénelon (1651-1715). C'est un roman pédagogique écrit pour l'éducation du due de Bourgogne, petit fils de Louis XIV. Publié en 1699, il remporta immédiatement un immense succès et fut l'objet de nombreuses rééditions dans les langues de l'Europe, au cours erne du 18[symbol omitted] siécle. Les spécialistes l'ont abordé sous l'angle : historique, sociologique, politique, économique, pédagogique, mystique, etc. Le but de la présente étude est de l'analyser d'un point de vue strictement littéraire. II a done d'abord fallu réfléchir sur la nature de l'expression littéraire (Introduction), ensuite preciser l'idée centrale qui donnait à l'oeuvre son caractére littéraire. Cette thèse a pour objet de démontrer qu'elle réside dans l'idee d'utopie. Le chapitre I définit les critères de l'utopie a partir du texte du Télémaque. Dans les chapitres suivants, ces criteres sont utilises a l'analyse : 1) de l'imagerie et de la structure thématique (CH.II); 2) de 11 organisation de l'utopie proprement dite de la ville de Salente (CH. Ill); 3) de la vision du monde qui sous-tend l'oeuvre et lui donne son unite (CH.IV). Le dernier chapitre enfin (CH.V) tente de montrer comment le style ne fait qu'un avec le fond et procède lui aussi de la vision utopique fondamentale.
An open, collaborative, and scholarly digital edition of Muḥammad Kurd ʿAlī's monthly journal al-Muqtabas (Cairo and Damascus, 1906-1917/18):  Volume 9
Creators: name: Grallert, Till
name: Manzi Tanna
name: Tobias Sick
name: Dimitar Dragnev
name: Dilan Hatun
name: Klara Mayer
name: Hans Magne Jaatun
name: Daniel Lloyd
Publisher: name: Zenodo
Year: 2020
Subjects: Arabic periodicals
Digital Scholarly Edition
Ottoman Empire
Damascus
Cairo
TEI XML

description: This release includes page breaks and structural mark-up validated against the facsimile for all twelve issues of volume 9. As always, this release includes corresponding bibliographic metadata for all articles and issues in this volume.

volumes:

1: complete

2: complete

3: complete

4: complete

5: complete

6: complete

7: complete

8: almost complete but publication dates need fixing

9: complete
The air pressure effect on the homogeneous nucleation of carbon dioxide by molecular simulation
Creators: name: Horsch, Martin
name: Lin, Zengyong
name: Windmann, Thorsten
name: Hasse, Hans
name: Vrabec, Jadran
Publisher: name: arXiv
Year: 2010
Subjects: subject: Atmospheric and Oceanic Physics (physics.ao-ph)
subject: Atomic and Molecular Clusters (physics.atm-clus)
subject: FOS: Physical sciences

description: Vapour-liquid equilibria (VLE) and the influence of an inert carrier gas on homogeneous vapour to liquid nucleation are investigated by molecular simulation for quaternary mixtures of carbon dioxide, nitrogen, oxygen, and argon. Canonical ensemble molecular dynamics simulation using the Yasuoka-Matsumoto method is applied to nucleation in supersaturated vapours that contain more carbon dioxide than in the saturated state at the dew line. Established molecular models are employed that are known to accurately reproduce the VLE of the pure fluids as well as their binary and ternary mixtures. On the basis of these models, also the quaternary VLE properties of the bulk fluid are determined with the Grand Equilibrium method. Simulation results for the carrier gas influence on the nucleation rate are compared with the classical nucleation theory (CNT) considering the "pressure effect" [Phys. Rev. Lett. 101: 125703 (2008)]. It is found that the presence of air as a carrier gas decreases the nucleation rate only slightly and, in particular, to a significantly lower extent than predicted by CNT. The nucleation rate of carbon dioxide is generally underestimated by CNT, leading to a deviation between one and two orders of magnitude for pure carbon dioxide in the vicinity of the spinodal line and up to three orders of magnitude in presence of air as a carrier gas. Furthermore, CNT predicts a temperature dependence of the nucleation rate in the spinodal limit, which cannot be confirmed by molecular simulation.
Additional file 2 of Methodological quality for systematic reviews of adverse events with surgical interventions: a cross-sectional survey
Creators: name: Zhou, Xiaoqin
name: Li, Linji
name: Lin, Lifeng
name: Ju, Ke
name: Kwong, Joey S. W.
name: Xu, Chang
Publisher: name: figshare
Year: 2021
Subjects: subject: Medicine
subject: Cell Biology
subject: Neuroscience
subject: Mathematical Sciences not elsewhere classified
subject: Cancer
subject: Mental Health
subject: Infectious Diseases
subject: FOS: Health sciences

description: Additional file 2. PROTOCOL.
Properties of dusty tori in active galactic nuclei - II. Type 2 AGN
Creators: name: Hatziminaoglou, Evanthia
name: Fritz, Jacopo
name: Jarrett, Tom
Publisher: name: arXiv
Year: 2009
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: (abridged) This paper is the second part of a work investigating the properties of dusty tori in AGN by means of multi-component SED fitting. It focuses on low luminosity, low redshift (z < 0.25) AGN selected among emission line galaxies as well as X-ray, radio and mid-infrared selected type 2 AGN samples from the literature. The available multi-band photometry covers the spectral range from the u-band up to 160 um. The observed SED of each object is fit to a set of multi-component models comprising a stellar component, a high optical depth torus and cold emission from a starburst (SB). The contribution of the various components (stars, torus, SB) is reflected in the position of the objects on the IRAC colour diagram. The comparison of type 1 (as derived from Hatziminaoglou et al. 2008) and type 2 AGN properties is broadly consistent with the Unified Scheme. The estimated ratio between type 2 and type 1 objects is about 2-2.5:1. The AGN accretion-to-infrared luminosity ratio is an indicator of the obscuration of the AGN since it scales down with the covering factor. We find evidence supporting the receding torus paradigm, with the estimated fraction of obscured AGN decreasing with increasing optical luminosity over four orders of magnitude. The average star formation rates are of ~ 10, 40 and 115 Mo/yr for the low-z, type 2 and quasar samples, respectively; but this might simply reflect observational biases, as our quasars are one to two orders of magnitude more luminous than the type 2 AGN. For the majority of objects with 70 and/or 160 um detections an SB component was needed in order to reproduce the data points, implying that the far-infrared emission in AGN arises mostly from star formation; moreover, the SB-to-AGN luminosity ratio shows a slight trend with increasing luminosity.
description: 20 pages, 23 figures, accepted for publication in MNRAS; full versions of tables 1-4 and Figs. 5, 14 and 15 only available as online material
The development of a new tracheal stenosis model in piglets and its repair with a free periosteal graft
Creators: name: Cohen, Ralph C
Publisher: name: University Of Tasmania
Year: 2023

description: Airway narrowing in-children from congenital stenosis or acquired stricture remains a difficult and challenging surgical problem. When the segment of tracheal stenosis is short, the best surgical treatment is to excise the stenosis and perform a primary end-to-end anastomosis. When there is an extensive segment of tracheal stenosis, this is clearly not possible and another means of enlarging the airway has to be devised. An appealing technique is to incise the stenotic segment longitudinally throughout its length, insert an endotracheal stent and then repair the resultant defect in the trachea with a suitable graft material. In this series of experiments, this technique is.examined in the thoracic segment of the piglet trachea. The study is performed in two phases. The initial experiments involve the normal trachea in which a, window defect is created over the entire length of the thoracic trachea involving 30% of its circumference. This defect represents that which would result when a stenotic segment of trachea is incised longitudinally. The window defect is then repaired with a free tibial periosteal graft. In the second phase, a model of tracheal stenosis is created by encircling the thoracic trachea with a silastic sheet. Once respiratory distress is established, the silastic sheet is removed at a second operation, and the stenotic segment incised, an endotracheal silastic stent inserted through the defect and the defect repaired with free tibial periosteal graft. The pigs are sacrified three months later when they have grown to about six times their original weight and the trachea removed. These studies demonstrate that free tibial periosteal grafts are an ideal biological material for repairing tracheal defects. The periosteum forms bone in a short period of time and supports the airway; the lumenal surface is lined with columnar and respiratory epithelium. This model suggests that tracheal stenosis in children may be surgically corrected by simply incising the stenotic segment longitudinally and enlarging the tracheal diameter by inserting a free periosteal graft into the defect.