Braided Type Research Articles

Universal knot diagrams

We study collections of planar curves that yield diagrams for all knots. In particular, we show that a very special class called potholder curves carries all knots. This has implications for realizing all knots and links as special types of meanders and braids. We also introduce and apply a method to compare the efficiency of various classes of curves that represent all knots.

Periodontal parameters of two types of 3 x 3 orthodontic retainer: a longitudinal study.

ABSTRACTIntroduction: bonded fixed retainers are often used to stabilize the results obtained with the orthodontic treatment. It is important that they do not prejudice dental health, as they will be used for a long period. Objective: The purpose of the present study was to compare periodontal indexes between two types of bonded fixed retainers, conventional 3 x 3 plain retainer (0.8-mm orthodontic wire, bonded to the canines only) and a manufactured braided retainer (0.2 x 0.7-mm stainless steel wire, bonded to all anterior teeth) after use. Methods: a test group of 15 volunteers (aged from 18 to 25 years) used both the conventional retainer and braided retainer for six months. A randomized longitudinal study design, with a two week washout interval, was applied. The dental plaque index, gingival index and dental calculus index were evaluated. Furthermore, the calculus accumulated along the retainer wire was measured and all patients answered a questionnaire about the use, acceptance and comfort of both types of retainers. Results: the scores for plaque and gingival indexes were higher for the braided retainer (p< 0.05) on the lingual and proximal surfaces. The same occurred with the calculus index on the lingual surfaces (p< 0.05). The calculus index along wire was higher for the braided retainer (p< 0.05). All patients preferred the conventional retainer, and said that it was also more comfortable to use. Conclusion: it was concluded that the conventional retainer showed better periodontal indexes than the braided type.

RUC-based multi-scale model for braid-reinforced polymers: Application to coil springs

As fiber- and braid-reinforced polymer components exhibit a vast number of additional design parameters compared to components made of monolithic materials, simulation methods are indispensable in the design and optimization process, accompanying or substituting experimental approaches. In respect thereof, we present a multi-scale approach comprising three observation scales: (i) the yarn scale considering fibers embedded in polymer, (ii) the braid scale capturing interwoven yarns, and (iii) the component scale. Information from one scale is transferred to the next higher scale by means of effective properties determined by finite element analysis of repetitive unit cell (RUC) models, subsequently applied for the determination of elastic properties on the yarn and braid scale. The depicted procedure allows the consideration of different types of braids (balanced and unbalanced regular braids) exhibiting arbitrary braid angles. Therefrom obtained effective properties enter the numerical model of the respective structural component. Finally, the multi-scale model is applied to the analysis of braid-reinforced polymer coil springs highlighting the potential of the proposed numerical approach. The obtained simulation results show excellent agreement with the respective experimental measurements and provide – additionally – insight into the stress distribution/loading within the coil as well as the sensitivity of design parameters with respect to the spring performance.

Trançados e letramentos : relatos de um projeto de Pesquisa e Prática Pedagógica na Escola Tupinikim da Aldeia Comboios- Aracruz/ES

O presente relato nasce de um projeto pedagógico desenvolvido na Aldeia Tupinikim de Comboios, município de Aracruz- ES, durante a disciplina Projetos de Pesquisa e Prática Pedagógica – PPPP III, no curso de Licenciatura Intercultural Indígena Tupinikim e Guarani, do Programa de Licenciaturas Indígenas – PROLIND, oferecido pela Universidade Federal do Espírito Santo – UFES. O projeto teve como objetivos: Pesquisar com os mais velhos os tipos de trançados, colaborando na reafirmação cultural do nosso povo Tupiniquim; Reconhecer os tipos de trançados Tupiniquim; Confeccionar alguns tipos de trançados; Produzir textos coletivos a partir dos trançados e analisar o processo de letramento a partir de atividades contextualizadas. O projeto se apoiou metodologicamente na pesquisa-ação com intuito de identificar as técnicas e manuseios dos trançados Tupinikim, construindo momentos de partilhas com os anciãos e intercâmbios entre outras aldeias Tupinikim.

Effect of the Abdominal Fascial Closure with Triclosan-Coated Sutures in Fecal Peritonitis, on Surgical Site Infection, and Evisceration: A Retrospective Multi-Center Study.

Surgical site infection (SSI) is a frequent complication in dirty surgery, reaching rates of up to 40%. The incidence of SSI might be influenced by the suture used for closure of the abdominal fascia. Sutures coated with antibacterial substances may reduce the bacterial load in the incision. A retrospective study of patients with intra-operative diagnosis of fecal peritonitis undergoing a laparotomy in three Spanish hospitals was performed. Fascial closure consisted in running loop suture of Polyglactin (Vicryl loop®, Johnson & Johnson, New Brunswick, NY; group 1), running loop suture of triclosan-coated polyglactin (Vicryl plus loop®; group 2), running loop suture of polydioxanone (PDS loop® Johnson & Johnson; group 3), and running loop suture of triclosan-coated polydioxanone (PDS plus loop®; group 4). Incisional SSI and evisceration rates were assessed. One hundred four patients were included. There were no differences in age, gender, comorbidities, etiology of peritonitis, and mortality among groups. Surgical site infection rate was 34.6% in group 1; 8% in group 2; 33% in group 3; and 10% in group 4 (p = 0.029). The use of triclosan-coated sutures is associated with lower risk of SSI (risk ratio [RR]: 9; p = 0.003). Evisceration rate was 0% in groups 1 and 2; 15.2% in group 3; and 10% in group 4 (p = 0.05). All patients suffering from evisceration presented previous SSI. The use of monofilament sutures is associated with higher risk of evisceration (RR: 6.35; p = 0.033). Triclosan-coated sutures reduce SSI rate in fecal peritonitis, without differences between braided and monofilament type. The use of monofilament sutures is related to higher risk of evisceration, independent of a triclosan coating.

Non-monotone periodic orbits of a rotational horseshoe

In this paper, we present results for the forcing relation on the set of braid types of periodic orbits of a rotational horseshoe on the annulus. Precisely, we are concerned with a family of periodic orbits, called the Boyland family, and we prove that for each pair$(r,s)$of rational numbers with$r&lt;s$in$(0,1)$, there exists a non-monotone orbit$B_{r,s}$in this family which has pseudo-Anosov type and rotation interval$[r,s]$. Furthermore, the forcing relation among these orbits is given by the inclusion order on their rotation sets. It is also proved that the Markov partition associated to each Boyland orbit comes from a pruning map which projects to a bimodal circle map. This family also contains the Holmes orbits$H_{p/q}$, which are the largest for the forcing order among all the$(p,q)$-orbits of the rotational horseshoe.

Experimental Test of Two Types of Non-Inductive Solenoidal Coils for Superconducting Fault Current Limiters Use

Growing electricity demand from a range of sources and the changes of the power grid structures open the possibility of more frequent and much higher fault current. Traditional solutions to the fault are difficult to satisfy the requirement of the new power grid due to many factors, such as high cost, additional impact to power grid in normal loading condition, which leads to the research for an efficient alternative solution of interest to both academia and industry: Superconducting fault current limiter (SFCL). In this paper, two types of low-inductance solenoidal coils, the braid type and the nonintersecting type, are built with 2G high-temperature superconductors. The current limiting performance, the recovery characteristics, and the ac losses of both types of coils are tested and compared in detail. Experimental results show that both types of coils can effectively limit fault current and recover in several seconds. Furthermore, comparison between the ac losses of both types of SFCLs shows that the ac loss of the braid type coil is lower than that of the single tape by about an order of magnitude in low-current regions.

Experimental analysis of diamond and regular tubular braided composites using three-dimensional digital image correlation

Braided composites can be manufactured in a variety of braid patterns: Diamond (1/1), Regular (2/2), and Hercules (3/3) and with longitudinal reinforcement (Triaxial). The complex strain fields, which could help reveal phenomenological behavior of braids, have not been experimentally assessed. As such, the objectives of this article were to investigate the effect of braid pattern (Diamond, Regular), braid angle (35°, 45°, 55°), and load (tensile, torsion) on the strain field and elastic properties (longitudinal and shear moduli) using a three-dimensional digital image correlation method. The methodology presented in this manuscript will be used to validate a new analytical model, which predicts the elastic properties of tubular braided of both varying braid type and braid angle.

Caracterización del patrón hidromorfológico del Arroyo de la Ventana en su tramo medio alto (Buenos Aires, Argentina)

En este trabajo se determina el patrón fluvial del Arroyo de la Ventana a través de las características hidrogeomorfológicas del tramo medio alto del curso fluvial. Se generó un Modelo Digital del Terreno (MDT) de la cuenca media-alta del curso en base a los datos de las curvas de nivel de la carta topográfica de Tornquist, a escala 1:50.000. La cartografía geomorfológica del curso fue realizada a partir de la información del vuelo fotogramétrico del año 1981 a escala 1:20.000. Asimismo se realizó un relevamiento in situ de tres secciones transversales del cauce. Se identificaron dos patrones fluviales diferenciados: tipo trenzado, en el tramo alto del curso y otro de tipo meandriforme en el tramo medio. La dinámica fluvial actual del curso muestra una tendencia general a la incisión en el tramo analizado.

탄소섬유를 이용한 600V 이하 저압 케이블의 전자파 차폐특성

This study used general carbon fibers(CF), which can be utilized for a low voltage cable screen, as well as metal-coated carbon fibers(MCF) to make cables and analyzed the properties of electromagnetic effectiveness. Both braid CF and MCF cables with 3,000 strands, 16 spindles, and braid density of 90% or over were adopted. The tape-type MCF specimens were spread into a tape(width: 15mm) using a hot melt to make a cable. The shield effectiveness was measured up to the 1GHz range in accordance with IEC 62153-4-6; braid shielded cables featured a superior shielding effect at 63dB than tape-type shielded cables. That was because the tape-type shielded cable has relatively more gaps and holes between carbon fibers than the braid type, resulting in a more inflow or emission of electromagnetic waves. In the case of braid cables, the characteristics of their electromagnetic waves were enhanced, with higher spindles and higher conductivity of carbon fibers. The shield effectiveness of the MCF shielded cable, however, was lower than that of tin-coated one.

AC loss modelling and experiment of two types of low-inductance solenoidal coils

Low-inductance solenoidal coils, which usually refer to the nonintersecting type and the braid type, have already been employed to build superconducting fault current limiters because of their fast recovery and low inductance characteristics. However, despite their usage there is still no systematical simulation work concerning the AC loss characteristics of the coils built with 2G high temperature superconducting tapes perhaps because of their complicated structure. In this paper, a new method is proposed to simulate both types of coils with 2D axisymmetric models solved by H formulation. Following the simulation work, AC losses of both types of low inductance solenoidal coils are compared numerically and experimentally, which verify that the model works well in simulating non-inductive coils. Finally, simulation works show that pitch has significant impact to AC loss of both types of coils and the inter-layer separation has different impact to the AC loss of braid type of coil in case of different applied currents. The model provides an effective tool for the design optimisation of SFCLs built with non-inductive solenoidal coils.

Channel deformations of the Irkut river in the Tunkinskaya depression

We examine the intrasecular morphodynamics of the Irkut river within the Tunkinskaya depression and the associated partitions between depressions. An analysis is made of the changes in the channel pattern in plan, and a typization is provided for the channel processes for three time intervals: 1914, 1975 and 2015. We identified eleven morphodynamically uniform reaches of the channel: three, one and seven of them are of the adapted, incised and broad-floodplain types, respectively. The types of morphodynamical development of the river are systematized, and reaches with a different degree of deformation are identified within the most mobile broad-band segment of the river in conditions of free meandering. It is ascertained that the reaches of the braided type and the reach with sharp loop-like bends are the most stable, which is, in either case, due to the consolidation of vegetation by the high floodplain which made it possible to stabilize the movement of the channel in plan. The most strongly altered reaches are determined, where river channel displacements were accompanied by a complete change of the morphodynamical types of bends; the macrobends mainly experienced a regular breakthrough or were complicated by lower-order bends. We identified the reaches with lower-order (local) changes where the development of the bends (for the most part, of the loop-like type) changed into a new evolutionary cycle). We determined the role played by the influence of the territory’s geologo-geomorphological structure, hydrological conditions and natural processes of channel evolution on the dynamics of homogeneous reaches, and on morphological changes within them. The period of the most significant channel deformations, from 1914 to 1976, was determined, which is accounted for by an enhancement in anthropogenic pressure and by the associated increase in suspended load, and the period of decrease in the magnitude of manifestations of channel deformations from 1976 to 2015.

Tensile behaviour of structurally gradient braided prostheses for anterior cruciate ligaments

Anterior cruciate ligament (ACL) is a key fibrous connective tissue that maintains the stability of a knee joint and it is the most commonly injured ligament of the knee. A synthetic prosthesis in the form of a braided structure can be an attractive alternative to biological grafts provided that the mechanical properties can be tailored to mimic the natural ACL. In the present work, the polypropylene based structurally gradient braided prostheses have been designed and developed by understanding their tensile properties. Circular braiding process was employed to fabricate structurally gradient braided prostheses by systematically placing different types of braids in defined set of layers. An analytical model for predicting the tensile properties of structurally gradient braided prostheses has been presented by modifying and combining the existing models available in the literature. Specifically, the full set of stress–strain behaviour of structurally gradient braided prostheses has been computed based upon braid structural characteristics, constituent strand properties and braid kinematics. A triaxial braid in the outer layer of braided prostheses was found to withstand higher tensile stresses in comparison to a biaxial braid having same structural characteristics. A comparison has been made between the theoretical and experimental results of tensile properties of structurally gradient braided prostheses. The tensile properties of structurally gradient braided prostheses predicted through analytical route matched reasonably well with the experimental results.

Geochemistry of Feldspar Intergrowth Microtextures from Paleoproterozoic Granitoids in Central India: Implications to Exsolution Processes in Granitic System

Abstract Various forms of feldspar intergrowth microtextures occurred in granitic rocks. Characteristically, two distinct types of microtextures formed due to intergrowth between K-feldspar and plagioclase i.e. perthites and myrmekites. Malanjkhand and Dongargarh granitoids are two contemporaneous units of Paleoproterozoic granitoids in central India. Three varieties of perthites have been identified in these granitoids i.e. flame, braid, and vein types. Flame perthite bearing K-feldspar is common. Braid and vein perthites occur occasionally. Paleopiezometry estimation indicates that flame perthite formed under the influence of low to moderate differential stress on granitoids. Most of the perthites occurs in these granitoids are compositionally albite to oligoclase in nature. The composition ranges XAb: 0.98-0.49 for the Malanjkhand and XAb: 0.96-0.49 for Dongargarh granitoids. Binary feldspar thermometry calculation indicates that perthites have formed at moderate to high temperature conditions in the Malanjkhand granitoid whereas low to moderate temperature conditions in Dongargarh granitoids during sub-solidus phase. Myrmekites is another feldspar intergrowth microtexture found in these granitoids. Myrmekites are identified in these granitoids based on their characteristic morphologies such as ghost, bulbous, rim, etc. These myrmekites were formed under moderate temperature conditions during magmatic-hydrothermal transition phase. Formation of flame perthite can be explained by replacement reaction mechanism (Na-K exchange) between K-feldspar and plagioclase under low to moderate differential stress condition during rapid cooling. Further, extensive deuteric alteration results in the formation of braid and vein perthites. Formation of myrmekites can be assumed by couple of replacement mechanisms (Na-K and Ca-K exchange) between K-feldspar and plagioclase. Paleopiezometry and feldspar thermometry results infer that orthomagmatic-hydrothermal transition in the Malanjkhand and Dongargarh granitoids were favored at upper or shallow levels in the continental crust.

Zmiany układu koryt Wisły spowodowane funkcjonowaniem stopnia wodnego „Włocławek” na podstawie analizy zdjęć lotniczych

In line with the classification after Brice (1975), the system of the contemporary Vistula channel may be identified as a complex anabranched (anastomosing) river system, consisting of the main channel of the braided river type with bars and islands, as well as meandering side channels separated by holms. In turn, following the views of Smith and Smith (1980), this system is in a transition phase from a braided to an anastomosing river system. The phase of transformation to an anastomosing one in the central and lower Vistula braided system could have started at the beginning of the Holocene and continued uninterrupted through to the present day (Starkel, 2001). Currently, the Vistula fluvial system changes in the vicinity of the dam on the Wloclawek reservoir and is under the strong influence of the anthropogenic impact the functioning of the dam is able to exert. To analyze the effects of this transformation, we have studied changes in channel structure using a method proposed by Brice and Blodgett (1978), as modified by Szmanda and Luc (2010). Analyzing aerial photographs, we have measured the widths of channels (w), as well as the lengths (L) and widths of bars (w’) and inter-channel forms in the bottom of the valley (islands fixed by vegetation and inter-channel areas called holms). Dimensionless parameters of forms were also calculated: L/w – for length, w’/w – for width, and L/w’ for shape. Aerial photographs from the area of the two holms located in the Vistula valley – i.e. the Bogpomoz Holm (below the Reservoir) and the Wykowska Holm (above it) were our research material. These photos come in both cases from two periods, before and after the construction of the dam in Wloclawek. The survey allowed the following conclusions to be drawn: (1) In the research period, the average width of the river channels below the dam has increased slightly, while above the barrier there has been a slight decrease. (2) By numbers of given forms, islands fixed by vegetation are found to be in the majority, whereas holms were more frequent in the floodplain inter-channel area. Irrespective of the type of form, most were elongated. (3) Both above and below the Reservoir, there has been a decrease in the number of (channel and valley) forms. The number of bars in the Vistula channel has decreased. The area of the inter-channel islands colonised by vegetation has increased through evolution in the direction of inter-channel and floodplain areas. As a result of the disappearance of the side arms, inter-channel areas have been absorbed by floodplains. (4) These processes have resulted in the slow preservation of the fixed multiple-channel fluvial system. We suggest calling this system an “anabranching river” as opposed to the classical anastomosing river (Smith and Smith, 1980).

Risk factors for technical failure of endoscopic double self-expandable metallic stent placement by partial stent-in-stent method.

Endoscopic double self-expandable metallic stent (SEMS) placement by the partial stent-in-stent (PSIS) method has been reported to be useful for the management of unresectable hilar malignant biliary obstruction. However, it is technically challenging, and the optimal SEMS for the procedure remains unknown. The aim of this study was to identify the risk factors for technical failure of endoscopic double SEMS placement for unresectable malignant hilar biliary obstruction (MHBO). Between December 2009 and May 2013, 50 consecutive patients with MHBO underwent endoscopic double SEMS placement by the PSIS method. We retrospectively evaluated the rate of successful double SEMS placement and identified the risk factors for technical failure. The technical success rate for double SEMS placement was 82.0% (95% confidence interval [CI]: 69.2-90.2). On univariate analysis, the rate of technical failure was high in patients with metastatic disease and unilateral placement. Multivariate analysis revealed that metastatic disease was a significant risk factor for technical failure (odds ratio: 9.63, 95% CI: 1.11-105.5). The subgroup analysis after double guidewire insertion showed that the rate of technical success was higher in the laser-cut type SEMS with a large mesh and thick delivery system than in the braided type SEMS with a small mesh and thick delivery system. Metastatic disease was a significant risk factor for technical failure of double SEMS placement for unresectable MHBO. The laser-cut type SEMS with a large mesh and thin delivery system might be preferable for the PSIS procedure.

Adaptive Algorithm for the Quality Control of Braided Sleeving

We describe the development and application of a robot vision based adaptive algorithm for the quality control of the braided sleeving of high pressure hydraulic pipes. With our approach, we can successfully overcome the limitations, such as low reliability and repeatability of braided quality, which result from the visual observation of the braided pipe surface. The braids to be analyzed come in different dimensions, colors, and braiding densities with different types of errors to be detected, as presented in this paper. Therefore, our machine vision system, consisting of a mathematical algorithm for the automatic adaptation to different types of braids and dimensions of pipes, enables the accurate quality control of braided pipe sleevings and offers the potential to be used in the production of braiding lines of pipes. The principles of the measuring method and the required equipment are given in the paper, also containing the mathematical adaptive algorithm formulation. The paper describes the experiments conducted to verify the accuracy of the algorithm. The developed machine vision adaptive control system was successfully tested and is ready for the implementation in industrial applications, thus eliminating human subjectivity.

Braided rivers: structure, types and hydrological effects

Braided rivers have been intensively analyzed mostly by geomorphologists. In the present study the approach to recognize braided channel types and effects with the special emphasis on flow partitioning has been applied. It is assumed that each braided channel represents the reach which is initiated with dividing of the single channel and completed below the confluence of the total multiplicity of channels. Proposed indices of braided channel structure and water discharges ratio which have been proposed and applied to 200 braided reaches of 40 rivers in Russia, China, and the USA enable the description of the origin and types of the observed rivers and further analysis of hydrological effects of braided channels. The latter represent physical, hydrochemical, and ecological conditions of stream along braided reaches caused by flow distribution among branches in relation to braiding intensity. Structure and braided channel pattern types impact on hydraulics, sediment transport, water temperatures, and stream communities are of primary interest in the present study.

What is the Relative Effect of Space and Time to Explain the Braided River Width and Island Patterns at a Regional Scale?

Several decades of human activities have severely impacted braided rivers worldwide. Despite their widespread disappearance, some remnant braided sectors are still held in the French Rhone basin, mainly in the south-east of France. In this paper, we analyse the evolutionary pattern of 53 braided reaches, focusing on the active channel width and island patterns, by comparing aerial photographs from the 1950s and 2000s (Institut Géographique National). Because different braided patterns exist (e.g. bar versus island-braided), we tested the relative effect of geographical and temporal factors. The hypothesis is that three main biogeomorphological braided types exist (i.e. defined through the presence, the amount and the relative size of vegetated islands), based on the combined effect of the following: (i) their position along the river network (i.e. river gradient, altitude and sediment regime) and (ii) the temporal effect represented by the time since the last large flood, that is, the recent flood history. Our results show that even if the regional context (climate and sediment regime mainly) plays a key role, the temporal factor, represented by recent flood history, seems to heavily influence the response of the width pattern and vegetation recovery. Local factors (i.e. topography and groundwater) may also have an impact, but their influence has no effect at the regional level. These results support braided river management (conservation and/or restoration actions) in the Rhone basin and provide a better understanding of the range of braided rivers' functioning. Further studies (e.g. multidate retrospective survey) are needed to better understand the role of flood events on braided pattern and vegetation recovery. Copyright © 2013 John Wiley & Sons, Ltd.

Turning numbers for periodic orbits of disk homeomorphisms

We study braid types of periodic orbits of orientation preserving disk homeomorphisms. If the orbit has period n, we take the closure of the nth power of the corresponding braid and consider linking numbers of the pairs of its components, which we call turning numbers. They are easy to compute and turn out to be very useful in the problem of classification of braid types, especially for small n. This provides us with a simple way of getting useful information about periodic orbits. The method works especially well for disk homeomorphisms that are small perturbations of interval maps.