Pathologies of the Peroneals: A Review

2020 ◽  
pp. 193864002091627
Author(s):  
Akhil Sharma ◽  
Selene G. Parekh

Peroneal tendon disorders remain an often overlooked source of lateral hindfoot pain and tenderness. Medical professionals who specialize in foot and ankle care are still far more likely to diagnose a peroneal tendon disorder as an ankle injury. In fact, acute peroneal dislocations are misdiagnosed in up to 40% of cases. The major subsets of peroneal disorders include peroneal tendonitis and tenosynovitis, painful os peroneum syndrome, subluxation, and tearing of the peroneal tendons. Proper history and physical exam maneuvers must be performed to help identify the source of the injury and differentiate these categories. Detailed imaging through X-ray and magnetic resonance imaging must also be used to diagnose the etiology of the patient’s condition in order to direct management. Currently, there is very limited knowledge on peroneal pathologies, and treatment protocol is highly variable and limited to expert opinion. Despite the individual preferences and nuances held by each surgeon when it comes to operating, the overarching principles that guide appropriate management of tendonitis, subluxation, and tendon tear should maintain a higher level of consistency. Therefore, the authors of this review aim to elucidate the most current methods to diagnose these disorders as well as evidence-based practices for optimal management. Levels of Evidence: Level V

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Robert Christie ◽  
Adrian Abel

Abstract This chapter provides an overview of the structural and synthetic chemistry, and the industrial applications, of dioxazine pigments, a small group of high performance organic pigments. The color violet (or purple) has frequently assumed a prominent position in history, on account of its rarity and cost. The natural colorant Tyrian purple and the first synthetic textile dye, Mauveine, are prime examples of this unique historical feature. CI Pigment Violet 23, also referred to as Dioxazine Violet or Carbazole Violet, is one of the most universally used organic pigments, by far the most important industrial pigment in the violet shade area. Dioxazine Violet is also unique as the dominant industrial violet pigment providing a brilliant, intense violet color and an excellent all-round set of fastness properties. The pigment has a polycyclic molecular structure, originally described wrongly as a linear arrangement, and later shown to adopt an S-shaped arrangement on the basis of X-ray structural analysis. Two other dioxazine pigments are of rather lesser importance. The synthesis and manufacturing route to CI Pigment Violet 23 is described in the review. Finally, a survey of the principal current applications of the individual dioxazine pigments is presented.


2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Hiroyuki Yamane ◽  
Masaki Oura ◽  
Osamu Takahashi ◽  
Tomoko Ishihara ◽  
Noriko Yamazaki ◽  
...  

AbstractAdhesion is an interfacial phenomenon that is critical for assembling carbon structural composites for next-generation aircraft and automobiles. However, there is limited understanding of adhesion on the molecular level because of the difficulty in revealing the individual bonding factors. Here, using soft X-ray spectromicroscopy we show the physical and chemical states of an adhesive interface composed of a thermosetting polymer of 4,4’-diaminodiphenylsulfone-cured bisphenol A diglycidyl ether adhered to a thermoplastic polymer of plasma-treated polyetheretherketone. We observe multiscale phenomena in the adhesion mechanisms, including sub-mm complex interface structure, sub-μm distribution of the functional groups, and molecular-level covalent-bond formation. These results provide a benchmark for further research to examine how physical and chemical states correlate with adhesion, and demonstrate that soft X-ray imaging is a promising approach for visualizing the physical and chemical states at adhesive interfaces from the sub-mm level to the molecular level.


Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 1986
Author(s):  
Andreas Koenig ◽  
Julius Schmidtke ◽  
Leonie Schmohl ◽  
Sibylle Schneider-Feyrer ◽  
Martin Rosentritt ◽  
...  

The performance of dental resin-based composites (RBCs) heavily depends on the characteristic properties of the individual filler fraction. As specific information regarding the properties of the filler fraction is often missing, the current study aims to characterize the filler fractions of several contemporary computer-aided design/computer-aided manufacturing (CAD/CAM) RBCs from a material science point of view. The filler fractions of seven commercially available CAD/CAM RBCs featuring different translucency variants were analysed using Scanning Electron Microscopy (SEM) with Energy Dispersive X-ray Spectroscopy (EDS), Micro-X-ray Computed Tomography (µXCT), Thermogravimetric Analysis (TG) and X-ray Diffractometry (XRD). All CAD/CAM RBCs investigated included midifill hybrid type filler fractions, and the size of the individual particles was clearly larger than the individual specifications of the manufacturer. The fillers in Shofu Block HC featured a sphericity of ≈0.8, while it was <0.7 in all other RBCs. All RBCs featured only X-ray amorphous phases. However, in Lava Ultimate, zircon crystals with low crystallinity were detected. In some CAD/CAM RBCs, inhomogeneities (X-ray opaque fillers or pores) with a size <80 µm were identified, but the effects were minor in relation to the total volume (<0.01 vol.%). The characteristic parameters of the filler fraction in RBCs are essential for the interpretation of the individual material’s mechanical and optical properties.


1949 ◽  
Vol 1 (3) ◽  
pp. 211-224
Author(s):  
G. B. Greenough

SummaryMany papers have been written on the measurement of strain by X-ray diffraction methods and on the interpretation of these strains in terms of stresses. Whereas, during the past few years, the experimental methods of determining the strains have. remained largely unchanged, research has shown that the older techniques for calculating stresses from strains are not always valid.In this paper an attempt is made to describe some of the principles of strain measurement by X-ray diffraction methods to those who are unfamiliar with the methods. The types of stress and strain systems which may exist in polycrystalline metals are then considered, particular attention being paid to the effect of the elastic and plastic anisotropy of the individual crystals. Some indication is given as to how the earlier methods of interpreting X-ray strain measurements should be modified, but no rigid routine method is proposed for use in a general case.


1986 ◽  
Vol 83 (1) ◽  
pp. 77-87 ◽  
Author(s):  
M.D. Kendall ◽  
A. Warley

Mast cell granules were examined by fully quantitative X-ray microanalysis of 20 cells in freeze-dried cryosections. The mast cells were situated mainly in the connective tissue of the thymic capsule of five adult male Carworth Sprague Europe rats. In addition 30 red blood cells were analysed from the same sections. Nineteen of the mast cells had granules rich in S and K. One cell had smaller granules, and in this cell the granules contained high [Ca] and [P] instead of high [S] and [K]. In the majority of cells (13) the S:K ratio was highly correlated and less than 2.2, whereas in the remaining six cells the individual granule ratios were very variable in any one cell and much higher. The mean granule [K] (994 +/− 57 mmol kg-1 dry wt) was about four times the mean cytoplasmic level of 227 +/− 81 mmol kg-1 dry wt. The existence of this difference in concentration between the granules and the cytoplasm suggests that the K in the granules must be bound. The relationship between the [K] and [S] is discussed with regard to the possible binding of heparin and amines in the granules.


Author(s):  
J Wittmann ◽  
G Herl ◽  
J Hiller

Abstract In 2018, 47 % of global internet users had purchased footwear products through the internet, making it the second most popular online shopping category worldwide right after clothing with 57 %. In the same year, on average, about every sixth parcel delivered in Germany (16.3 %) was returned. With the effort and costs that are associated with the return of shoes, the objective of reducing the number of returns for shoes promises an enormous economic potential and helps to reduce the CO2 emissions due to a lower trafic volume. This paper presents a workflow for determining the inside volume surface of shoes using industrial X-ray computed tomography (CT). The fundamental idea is based on the Region Growing (RG) method for the segmentation of the shoe's inner volume. Experiments are performed to illustrate the correlation of image quality and segmentation result. After obtaining the 3D surface model of an individual foot, the inner volume surface data of a scanned shoe can then be registered and evaluated in order to provide a reliable feedback for the customer regarding the accuracy of fit of a shoe and the individual foot on the basis of an overall "metric of comfort" before buying online. This step is not part of the work at hand. Conclusions are drawn and suggestions for improving the robustness and the exibility of the workflow are given, so it can be adapted to various shoe types and implemented in a fully automated measurement process in the future.


2021 ◽  
Vol 28 (3) ◽  
Author(s):  
A. M. Kalitenko

A numerical study of the effect of betatron oscillations on the second harmonic generation in free-electron lasers (FELs) is presented. Analytical expressions for the effective coupling strength factors are derived that clearly distinguish all contributions in subharmonics and each polarization of the radiation. A three-dimensional time-dependent numerical FEL code that takes into account the main FEL effects and the individual contribution of each electron to the second harmonic generation is presented. Also, the X- and Y-polarizations of the second harmonic are analyzed. The second harmonic was detected in experiments at the Advanced Photon Source (APS) Low Energy Undulator Test Line (LEUTL) and Linac Coherent Light Source (LCLS) in the soft X-ray regime. The approach presented in the article can be useful for a comprehensive study and diagnostics of XFELs. In the paper, the LCLS and Pohang Accelerator Laboratory X-ray Free-Electron Laser (PAL-XFEL) experiments are modeled. The simulation results are in a good agreement with the experimental data.


2021 ◽  
Vol 15 (2) ◽  
pp. 128-132
Author(s):  
Rodrigo Guimarães Huyer ◽  
Mário Sérgio Paulillo Cillo ◽  
Carlos Daniel Cândido Castro Filho ◽  
Hallan Douglas Bertelli ◽  
Renato Morelli Berg

Objective: To assess postoperative clinical functional outcomes, based on the American Orthopaedic Foot & Ankle Society (AOFAS) score, of tendoscopies performed in the treatment of foot and ankle pathologies. Methods: Our comparative assessment used AOFAS scores obtained preoperatively and at early and late postoperative stages - 1 month and 6 to 12 months after surgery - of 14 patients with foot and ankle tendinopathies. These included peroneal tendon dislocation, peroneal tendonitis, and tearing of the peroneus longus or brevis, all treated with tendoscopy for peroneal reconstruction and tenorrhaphy. The AOFAS score was obtained by functional assessment during outpatient physical examination. We presented a descriptive analysis of cases, comparing scores over time through the Friedman test followed by Dunn’s test. The relationship between score variations and sex was assessed using the Mann-Whitney test; their comparison with age used Spearman’s linear correlation coefficient. Significance levels were 5%.Results: The AOFAS score showed important improvements such as preoperative scores of 56 and 67 followed by postoperative scores of 100 both in the early and late stages, supporting the efficacy and persistence of this treatment strategy. The p-value obtained after statistical analysis was <0.0001. Conclusion: We concluded that the treatment of foot and ankle comorbidities with tendoscopy, in addition to being less invasive, shows consistency and efficacy as demonstrated by the AOFAS score and functional assessment via postoperative physical examinations. AOFAS scores were increased and maintained at high levels in the postoperative period, demonstrating the efficacy of this procedure and the duration of treatment results. Level of Evidence IV; Case Series; Therapeutic Studies - Investigation of Treatment Results.


2021 ◽  
Author(s):  
Harry Geddes ◽  
Henry D. Hutchinson ◽  
Alex R Ha ◽  
Nicholas P. Funnell ◽  
Andrew Goodwin

<div> <div> <div> <p>Using a non-negative matrix factorisation (NMF) approach, we show how the pair distribution function (PDF) of complex mixtures can be deconvolved into the contributions from the individual phase components and also the interface between phases. Our focus is on the model system Fe||Fe3O4. We establish proof-of-concept using idealised PDF data generated from established theory-driven models of the Fe||Fe3O4 interface. Using X-ray PDF measurements for corroded Fe samples, and employing our newly-developed NMF analysis, we extract the experimental interface PDF (‘iPDF’) for this same system. We find excellent agreement between theory and experiment. The implications of our results in the broader context of interface characterisation for complex functional materials are discussed. </p> </div> </div> </div>


2021 ◽  
Vol 28 (4) ◽  
Author(s):  
Selwin Hageraats ◽  
Mathieu Thoury ◽  
Stefan Stanescu ◽  
Katrien Keune

X-ray linear dichroism (XLD) is a fundamental property of many ordered materials that can for instance provide information on the origin of magnetic properties and the existence of differently ordered domains. Conventionally, measurements of XLD are performed on single crystals, crystalline thin films, or highly ordered nanostructure arrays. Here, it is demonstrated how quantitative measurements of XLD can be performed on powders, relying on the random orientation of many particles instead of the controlled orientation of a single ordered structure. The technique is based on a scanning X-ray transmission microscope operated in the soft X-ray regime. The use of a Fresnel zone plate allows X-ray absorption features to be probed at ∼40 nm lateral resolution – a scale small enough to probe the individual crystallites in most powders. Quantitative XLD parameters were then retrieved by determining the intensity distributions of certain diagnostic dichroic absorption features, estimating the angle between their transition dipole moments, and fitting the distributions with four-parameter dichroic models. Analysis of several differently produced ZnO powders shows that the experimentally obtained distributions indeed follow the theoretical model for XLD. Making use of Monte Carlo simulations to estimate uncertainties in the calculated dichroic model parameters, it was established that longer X-ray exposure times lead to a decrease in the amplitude of the XLD effect of ZnO.


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