Frictional coupling between sliding and spinning motion

We show that the friction force and torque, acting at a dry contact of two objects moving and rotating relative to each other, are inherently coupled. As a simple test system, a sliding and spinning disk on a horizontal flat surface is considered. We calculate, and also measure, how the disk is slowing down, and find that it always stops its sliding and spinning motion at the same moment. We discuss the impact of this coupling between friction force and torque on the physics of granular materials.Comment: 4 pages, 5 figures; submitte

Methodology for evaluating LCC

Evaluating the life cycle costs (LCC) of food waste is a challenging task and few examples of previous LCC exist. This REFRESH report reviewed existing measures and methods for the evaluation of LCC of food waste. It conducted a comprehensive literature review to identify major methodological challenges related to cost modelling and externalities. The report contributes to the development of recommendations for a standardized system approach

On the Nature of Intrinsic Absorption in Reddened Seyfert 1 Galaxies

We discuss the origin of the ``dusty lukewarm absorber'', which we previously identified in the reddened Seyfert 1 galaxies NGC 3227 and Akn 564. This absorber is characterized by saturated UV absorption lines (C IV, N V) near the systemic velocity of the host galaxy, and is likely responsible for reddening both the continuum and the emission lines (including those from the narrow-line region) from these Seyferts. From a large sample of Seyfert 1 galaxies, we find that continuum reddening (as measured by UV color) tends to increase with inclination of the host galaxy. Furthermore, reddened, inclined Seyfert galaxies observed at moderate to high spectral resolution all show evidence for dusty lukewarm absorbers. We suggest that these absorbers lie in the plane of the host galaxy at distances > 100 pc from the nucleus, and are physically distinct from the majority of intrinsic absorbers that are outflowing from the nucleus.Comment: 14 pages, including 2 figures, accepted for publication in the Astrophysical Journal (Letters

Resonant continuum in the Hartree-Fock+BCS approximation

A method for incorporating the effect of the resonant continuum into Hartree-Fock+BCS equations is proposed. The method is applied for the case of a neutron-rich nucleus calculated with a Skyrme-type force plus a zero-range pairing interaction and the results are compared with Hartree-Fock-Bogoliubov calculations. It is shown that the widths of resonant states have an important effect on the pairing properties of nuclei close to the drip line.Comment: 9 pages, 2 figures, comparison with HFB adde

Rational Moral Ignorance

Philosophy and Phenomenological Research, EarlyView

Computing NodeTrix Representations of Clustered Graphs

NodeTrix representations are a popular way to visualize clustered graphs; they represent clusters as adjacency matrices and inter-cluster edges as curves connecting the matrix boundaries. We study the complexity of constructing NodeTrix representations focusing on planarity testing problems, and we show several NP-completeness results and some polynomial-time algorithms. Building on such algorithms we develop a JavaScript library for NodeTrix representations aimed at reducing the crossings between edges incident to the same matrix.Comment: Appears in the Proceedings of the 24th International Symposium on Graph Drawing and Network Visualization (GD 2016

АЛЛОГЕННЫЕ КОСТНОПЛАСТИЧЕСКИЕ МАТЕРИАЛЫ: СОВРЕМЕННОЕ СОСТОЯНИЕ ПРОБЛЕМЫ

Worldwide population aging and associated with it epidemics of osteoporosis, widespread of bone and joint reconstructive surgery and first of all joint replacement lead to explosive growth of interest in bone grafting.Although autografts are still the golden standard in bone regeneration, allogeneic bone substitutes have reached a state that allows for their application with satisfying clinical results. However, it has repeatedly been supposed that the different allogeneic materials underwent different purification processes, which modifies bone regeneration properties of these materials and also for different safety conditions. In the present publication, the treatment of the precursor tissue, the safety conditions, and the regenerative possibilities of C+TBA bone blocks based in preclinical and clinical data are described. Thus, it is described how the risks of infections and also immunological reactions becomes completely eliminated, while the special purification process allows for preservation of the native structure of the bone block. Both the in vitro studies and the clinical trials including histological follow-ups showed the optimal regeneration properties of these bone blocks. It has been shown that the allogeneic bone grafts have been integrated without causing inflammatory anomalies at the implantation site. Altogether, the allogeneic bone substitute material serves as an excellent basis for the formation of new bone. Finally, the combination of the allogeneic C+TBA bone blocks with different antibiotics is described. Interestingly, it is possible to combine the allogeneic bone substitute ether with antibiotics in the sense of prophylaxis and/or with bone marrow aspirate in order to accelerate bone remodeling.Старение населения планеты и ассоциированная с ним эпидемия остеопороза, а также широкое распространение реконструктивных операций на костях и суставах, в первую очередь эндопротезирования, привели к взрывному росту интереса к костной пластике.Несмотря на то, что аутотрансплантаты по-прежнему остаются «золотым стандартом» при замещении костных дефектов, аллогенные костнозамещающие материалы достигли такого уровня качества, который позволяет с успехом применять их в клинической практике. Неоднократно высказывались предположения, что разные способы обработки различных типов аллогенных материалов по-разному меняют их регенеративные свойства и характеристики безопасности. В статье описана технология обработки исходного материала, перечислены требования к безопасности аллокости, регенеративные возможности костных блоков C+TBA. Приводятся подтверждающие данные доклинических и клинических исследований. Технология C+TBA позволяет практически полностью исключить риск развития иммунологических реакций и передачи инфекции, а специальные этапы обработки позволяют сохранить естественную структуру костного блока. Клинические и in vitro исследования с гистологическим контролем на разных этапах показали оптимальные регенеративные характеристики таких костных блоков. Аллогенная кость интегрировалась, не вызывая локальных воспалительных реакций в месте трансплантации. В целом аллогенные костнозамещающие материалы являются отличной основой для формирования новой кости. В статье описаны комбинации аллогенных костных блоков C+TBA с различными антибиотиками с целью профилактики инфекции и/или с пунктатом костного мозга для стимуляции перестройки кости

The instability of Alexander-McTague crystals and its implication for nucleation

We show that the argument of Alexander and McTague, that the bcc crystalline structure is favored in those crystallization processes where the first order character is not too pronounced, is not correct. We find that any solution that satisfies the Alexander-McTague condition is not stable. We investigate the implication of this result for nucleation near the pseudo- spinodal in near-meanfield systems.Comment: 20 pages, 0 figures, submitted to Physical Review

Summary of ISO/TC 201 International Standard ISO 18516:2019 Surface chemical analysis—Determination of lateral resolution and sharpness in beam-based methods with a range from nanometres to micrometres and its implementation for imaging laboratory X-ray photoelectron spectrometers (XPS)

ISO 18516:2019 Surface chemical analysis—Determination of lateral resolution and sharpness in beam-based methods with a range from nanometres to micrometres revises ISO 18516:2006 Surface chemical analysis—Auger electron spectroscopy and X-ray photoelectron spectroscopy—Determination of lateral resolution. It implements three different methods delivering parameters useful to express the lateral resolution: (1) the straight edge method, (2) the narrow line method and (3) the grating method. The theoretical background of these methods is introduced in ISO/TR 19319:2013 Surface chemical analysis—Fundamental approaches to determination of lateral resolution and sharpness in beam-based methods. The revised International Standard ISO 18516 delivers standardized procedures for the determination of the (1) effective lateral resolution by imaging of square-wave gratings, the (2) lateral resolution expressed as the parameter D12–88 characterizing the steepness of the sigmoidal edge spread function (ESF) determined by imaging a straight edge and (3) the lateral resolution expressed as the full width of half maximum of the line spread function (LSF), wLSF, determined by imaging a narrow line. The last method also delivers information on the shape of the LSF, which characterizes an individual imaging instrument. Finally, the implementation of all three standardized methods in the field of imaging laboratory X-ray photoelectron spectroscopy (XPS) is shortly presented. This part of the letter is based on the use of a new test sample developed at ETH Zurich, Switzerland. This test sample displays a micrometre scaled pattern motivated by the resolving power of recent imaging XPS instruments

Signatures of hermitian forms and the Knebusch Trace Formula

Signatures of quadratic forms have been generalized to hermitian forms over algebras with involution. In the literature this is done via Morita theory, which causes sign ambiguities in certain cases. In this paper, a hermitian version of the Knebusch Trace Formula is established and used as a main tool to resolve these ambiguities. The last page is an erratum for the published version. We inadvertently (I) gave an incorrect definition of adjoint involutions; (II) omitted dealing with the case $(H\times H, \widehat{\phantom{m}}\,)$. As $W(H\times H, \widehat{\phantom{m}}\,)= W(R\times R, \widehat{\phantom{m}}\,)=0$, the omission does not affect our reasoning or our results. For the sake of completeness we point out where some small changes should be made in the published version.Comment: This is the final version before publication. The last page is an updated erratum for the published versio