Type Of Deformation Research Articles

Modified Alar Base Reduction: A Novel Technique.

Alar base reduction (ABR) surgery is one of the rhinoplasty techniques used to reduce alar flaring, nasal base width, or both. It is crucial for rhinoplasty surgeons to understand and analyze the type of nasal base deformity to achieve satisfactory results and avoid complications. The objective of this study is to describe a novel technique of ABR that addresses alar flaring while avoiding violation of the nostril marginal rim. This prospective cohort study included patients with alar flaring who underwent rhinoplasty or septorhinoplasty with ABR using our modified technique. Demographic data, clinical history, aesthetic concerns, and preoperative and postoperative photographs were collected for each patient. The surgical outcome was assessed using subjective scar evaluation scores at 3 and 6 months, the Stony Brook Scar Evaluation Scale at 6 months, and an overall appearance satisfaction score. A total of 8 patients were included in the study. Subjectively, the majority of patients (75%) reported satisfactory scar appearance at the 6-month follow-up. The mean Stony Brook score was 4.7 (SD=0.74). Nostril symmetry was achieved in all patients. Seventy-five percent of the participants expressed satisfaction with the overall appearance. Our modified ABR technique demonstrates promising results in correcting alar flaring while achieving nostril symmetry with an acceptable scar. Further studies with a larger sample size are needed to evaluate the feasibility of the technique and compare it to other classical techniques. Level IV.

Real-time pore structure evolution difference between deep and shallow coal during gas adsorption: A study based on synchrotron radiation small-angle X-ray scattering

Coal seam CO2 sequestration is an important option to address global warming. A better knowledge on coal pore structure evolution during gas adsorption can provide guidance for coal seams CO2 sequestration. However, few investigations on the pore structure evolution differences between the deep and shallow coal were conducted during gas adsorption. In this study, based on the real-time synchrotron radiation small-angle X-ray scattering (SAXS) observation, the average pore diameter and pore surface fractal dimension evolution differences between deep and shallow coal were investigated from the aspects of coal compositions and stress history. Two types of coal deformation (inner-swelling and outer-swelling) coexist during gas adsorption. Coal compositions have significant impact on the dominance of deformation type. The dominance of inner-swelling in deep coal is induced by the higher ash contents, and there is the decrease of average pore diameter during gas adsorption. The impact of stress-history (burial depth) on adsorption-induced deformation is more prominent than that of gas adsorption capacity. In deep coal, the surface fractal dimension evolution presents a negative correlation with the evolution of pore diameters. In shallow coal, the surface fractal dimension evolution presents a Langmuir-type correlation with the adsorption time.

Краниологическое исследование черепов из двух гуннских погребений из Крыма (Усть-Альминский некрополь, IV–V вв. н. э.)

Introduction. The invasion of the Huns in Europe, which became the cause of the Great Migration of peoples, could not but leave a significant archaeological trace. However, only a small number of Hun burials are currently known, most of which were discovered accidentally in the middle of the 20th century, which makes each newly discovered burial unique, and their comprehensive study and publication of individual data is important for subsequent research. Materials and methods. During the excavations in 2021–2022, two Hun burials were discovered in the Ust-Alma necropolis. One of them belonged to a young man, the second to an elderly woman. The good preservation of both skeletons, in particular their skulls, allowed for a complete craniological examination. In addition, a children's Hun skull from the Belyaus settlement was examined, which is in permanent storage at the D. N. Anuchin Research Institute and Museum of Anthropology. Results. As a result of the work carried out, it was found that both individuals from Ust-Alma have the same type of skull deformation – high annular (according to the classification of E.V. Zhirov). However, the deformation methods were probably different. The deformation of the skull of a child from Belyaus is defined as occipital with right-sided asymmetry of the occiput. Craniophenetic data do not indicate the relationship of individuals buried in the Ust-Alminsky burial ground. Craniometric data indicate a mixed origin of the crimean Huns. Conclusion. Due to the small number of Hun burials from Ust-Alma, as well as individual data on Hun skulls in the scientific literature, it is difficult to conduct a statistical analysis based on craniological data. Within the typological approach, for a number of features, the male skull was characterized as Caucasoid, and the female as Mongoloid. Thus, new craniological data on rare Hunnic skulls introduced into scientific circulation will increase the comparative base for further research. @ 2023. This work is licensed under a CC BY 4.0 license

Sequence-Dependent Properties of the RNA Duplex.

Sequence-dependent properties of the DNA duplex have been accurately described using extensive molecular dynamics simulations. The RNA duplex meanwhile─which is typically represented as a sequence-averaged rigid rod─does not benefit from having equivalent molecular dynamics simulations. In this paper, we present a massive simulation effort using a set of ABC-optimized duplexes from which we derived tetramer-resolution properties of the RNA duplex and a simple mesoscopic model that can represent elastic properties of long RNA duplexes. Despite the extreme chemical similarity between DNA and RNA, the local and global elastic properties of the duplexes are very different. DNA duplexes show a complex and nonelastic pattern of flexibility, for instance, while RNA duplexes behave as an elastic system whose deformations can be represented by simple harmonic potentials. In RNA duplexes (RNA2), not only are intra- and interbase pair parameters (equilibrium and mechanical) different from those in the equivalent DNA duplex sequences (DNA2) but the correlations between movements also differ. Simple statements on the relative flexibility or stability of both polymers are meaningless and should be substituted by a more detailed description depending on the sequence and the type of deformation considered.

Incidence of genitourinary anomalies in congenital scoliosis: systematic review and meta-analysis.

The main objective of this study was to assess the overall incidence of genitourinary anomalies in patients with congenital scoliosis by providing the highest level of evidence. The secondary objective was to look for associations and trends influencing the incidence. A meta-analysis using PubMed, Embase, Scopus, and the Cochrane Collaboration Library database was carried out. We included studies focusing on patients with congenital scoliosis and genitourinary anomalies. The main outcome was the incidence of genitourinary anomalies in congenital scoliosis. We also collected the following data: patient gender, type of deformity (formation, segmentation, or mixed), deformity location, and associated anomalies. We included cohort studies. Data was extracted from published reports and combined using Review Manager 5.4. The quality of the included studies was assessed independently by two authors using the Methodological Index for Non-Randomized Studies (MINORS) criteria. A total of eight cohort studies were included from a pool of 2781 patients. The incidence of genitourinary anomalies associated with congenital scoliosis was 22.91% (95% CI 13.39-32.43%). The incidence of surgically treated genitourinary anomalies was 13.92% (95% CI 4.54-23.31%). There were no differences related to gender (male 49.3% versus female 50.7%; p > 0.05). There were no differences regarding the type of deformity. The incidences of associated intraspinal, cardiac, musculoskeletal and craniofacial anomalies were 33.30%, 17.60%, 27.77% and 19.83% respectively. The most frequent genitourinary anomalies were: unilateral kidney (111/388); renal ectopia (50/367); obstructive uropathy (30/201), horseshoe kidney (30/313) and undescended testicle (16/180). The incidence of genitourinary anomalies associated with congenital scoliosis was 22.91%, and 13.92% were surgically treated. Unilateral kidney was the most common genitourinary abnormality. There were no differences between genders and deformity types. It is important to consider the association between genitourinary anomalies and intraspinal or musculoskeletal anomalies.

An isoparametric quadratic boundary element for coupled stretching-bending analysis of thick laminated composite plates with transverse shear deformation

Recently, we derived the Green's function for an infinite thick laminated composite plate subjected to concentrated forces and moments. By serving this Green's function as the fundamental solutions, in this paper for the first time we develop the associated boundary element method (BEM), which is applicable to general problems of thick laminated plates with various types of deformations. For example, the in-plane stretching and out-of-plane bending deformations may be coupled together, which occurs for the unsymmetric laminated composite plates. Besides, the transverse shear deformations are also incorporated based upon the first order plate theory. To complete the entire development of the proposed BEM, all the involved issues, such as the boundary integral equations, the fundamental solutions and their derivatives, the mathematical formulation for the selected isoparametric quadratic boundary element, and the treatments of singular integrals are elaborated in this paper. The calculations of complete solutions at boundary or internal points are provided as well. The accuracy and efficiency of the proposed BEM are demonstrated through numerical examples, which show that it outperforms the conventional finite element method and is applicable for general thick laminated plates with unrestricted coupling effects.

Acquired Radial Club Hand: An Algorithm to Manage Radial Deficiency.

Introduction Loss of radius either due to trauma or infection results in a deformity resembling a congenital radial club hand. This deformity results in difficulty to perform hand functions and cosmetic appearanceand is called acquired radial club hand. There are a few case reports for the treatment of this severe deformity, but there are no proper guidelines for the management of this disease. From our experience, we decided to provide treatment guidelines for acquired radial club hand. Objectives To evaluate the outcome of radial deformity treatment in acquired radial club hand injuries and develop a treatment algorithm. Patients and methods It is a case series study of 11 patients with acquired radial club hand. It was conducted at a tertiary care hospital in Pakistan, from year 2016 to 2022. Basic principles of management of infection and trauma were followed. For the treatment of radial deformity, different options were opted according to the type of deformity, following the principles of treatment of congenital radial club hand. The outcome was graded on functional activity, pain, and bony union. Results Out of 11 patients, 36.36% showed excellent results, 27.27% showed good results, 27.27% showed fair results, and 9.09% showed poor results. Results were excellent in all patients with avascularized bone graft and distraction lengthening, with or without the Darrach procedure. Of the patients in whom distraction lengthening was performed, one patient showed excellent results while the other patient achieved similar results after the Darrach procedure of ulnar shortening. In the case of one bone formation by radioulnar synostosis, the results were variable. Two of the patients showed good outcomes while the other two had fair outcomes. Results in the case of ulnar centralization were mixed with good, fair, and poor results in one patient each. After three months of follow-up, 87% of the patients showed fair to excellent results. Conclusion With our experience, we recommend an algorithm for the treatment of acquired radial club hand.

Design of Composite Parallel External Fixator for Multisegment Foot and Ankle Deformity Correction: A Correction Requirement- Dominated Approach

Foot and ankle deformity is a common complaint in orthopedic surgery, among which the multisegment concurrent types are even more severe. As a key medical device for multisegment deformity correction, the composite parallel external fixator (PEF) design has a profound impact on the correction outcomes. However, existing PEFs share a single configuration and have inadequate adaptation to various deformity types, leading to problems, such as complex structural composition, excessive adjustment parameters, and uncomfortable wearing experience. To overcome these problems, this article proposes a novel correction requirement-dominated design approach for composite PEF. Multisite frame mounting modes and multitype struts are introduced to form required PEF configurations. Lower mobility struts can constrain the unwanted degrees-of-freedom, thus enabling the device to precisely match the requirement-function relationship. Taking the double-segment deformity as research object, clinical cases, and composite PEF assembly simulations are provided. Experiments are carried out on the mechanical prototype. The mounting test proves the interconverting ability and deformity-targeting property of the derived composite PEFs. Moreover, the motion test verifies that the device can distract patients of different weights to complete the correction path, and the stability test demonstrates that the device can resist external bumps, thus indicating the feasibility of the approach.

Sedimentary Records of Liquefaction: Implications From Field Studies

AbstractThe susceptibility of grains in sediment to the liquefaction process causes the development of deformation structures. Some sediments undergo liquefaction, others do not. There is a group of sediments especially prone to liquefaction, which was proven during laboratory experiments. However, the field results are often slightly different from those obtained experimentally because of many unpredictable factors influencing the course of the liquefaction process. For this reason, we tested 144 samples of unconsolidated Quaternary‐age sediments, collected from eight study sites in Germany, Lithuania and Latvia, which have been liquefied. We also present some new dating results. These samples were divided into two groups of soft‐sediment deformation structures: concave up (e.g., injection structures) and concave down (e.g., load casts, pseudonodules). The granulometry of all deformation types was statistically evaluated, which allowed identifying textural differences between sediment contained in concave up and concave down structures. We suggest that the mobilization of silt fraction is responsible for the further deforming process. We also confirm that the maximum content of clay in sediment prone to liquefaction cannot exceed 14%, but only with a significant content of coarser fractions (silt and sand). Moreover, we identified two separate zones of the specific grain size in which only concave down structures or only concave up structures develop as an effect of liquefaction, and the third “transitional zone” where all forms occur. The “transitional zone” is separated from the concave up structures and concave down structures zones by two “gap zones” in which no liquefied sediments were observed.

Spin-induced ferroelastics with pyrochlore lattices

Spin ordering in the geometrically frustrated magnetic materials with pyrochlore lattices is a key player in the emergent phenomena in modern condensed matter. A possible spin-ordered phases derived from the archetypical pyrochlore lattice were studied within the Landau conception of order parameter (OP) for case wavevector k = (0,0,0) associated with the center of the Brillouin zone of space group The existence of 20 low-symmetry types of spin-ordered phases is established. For each phase space group and set of proper and improper OPs are defined. Only one phase generated by irrep mГ2 + is not ferroelastic. The fundamental feature of spin-ordered phases in the pyrochlore lattices is that all remaining 19 phases found are improper ferroelastics. The Г5 + (a,a,a) shear deformation, involved in the formation of phases with space groups and is proved to be the only one that contributes to the formation of these rhombohedral distorted spin-ordered phases. Other types of shear deformations Г5 +(a,0,0) and Г5 +(a,b,b) are always cooperate with some of the Г3 + deformations at the formation of spin-ordered pyrochlores.

Investigation of Dry Sliding Wear Behavior of CFRP Composite Used in New Generation Aircraft Wings

In this study, it is aimed to examine the effect of reinforcement laying angle on wear resistance of CFRP composites used in the automotive and aerospace industries. Experiments were carried out on Ball-On-Disc wear device under 1, 3 and 5 N loads at room temperature. 3D optical microscope was used to determine the volume losses in the samples. The worn surface morphology of the samples was examined with the help of SEM (Scanning Electron Microscopy). In the test results, the volume losses of the samples increased depending on the increasing loads and shear rate. It has been understood that the change of the laying angle is important in the dry-sliding resistance of the samples. The wear resistance of the samples produced with 45 degree laying was better at both sliding speeds and all loads. It has also been understood that the laying angle is also effective in the coefficient of friction. Delamination, plastic deformation type dominant wear mechanisms have occurred.

Skeletal deformities in gilthead seabream (Sparus aurata): exploring the association between mechanical loading and opercular deformation

Fish aquaculture is frequently confronted with skeletal abnormalities. In gilthead seabream (Sparus aurata (Linnaeus, 1758)), opercular deformities are one of the most common types of deformities. Many studies point at potential causal factors, mainly genetic or nutritional. However, no clear consensus has surfaced yet, and other factors known to affect bone formation remain unexplored, including mechanical stressors by external forces or muscle contraction. In this study, we investigated whether an altered mechanical use of the gill cover could be associated with opercular deformities, by inducing a change in the respiratory rate and thus gill ventilation. Juvenile seabreams were reared under 80, 100 or 200% dissolved oxygen (DO) to trigger altered respiration behaviour, and the effect on body and opercular shape was analysed. The main hypothesis was that hypoxic conditions would increase opercular ventilation, which would result in a higher prevalence of opercular deformities. The results show that the hypoxic condition (80% DO) did not trigger a significantly higher prevalence of opercular deformations, though the opposite is true for the hyperoxic condition (200% DO). No effect of oxygen treatment was observed on overall body shape, though deformed opercles showed a pronounced, but non-significant difference in shape across treatments. Morphometric results and µCT scans reveal that deformations mainly occur in the dorsocaudal region of the opercular bone. Although no causal link could be demonstrated, we discuss how these results can indirectly suggest that an altered mechanical loading on the operculum could explain its deformation.

Promotion of mitochondrial fragmentation suppresses the formation of mitochondrial spherical compartmentation in PINK1B9Drosophila melanogaster

Mitochondria undergo structural changes reflective of functional statuses. Ultrastructural characterizing of mitochondria is valuable for understanding mitochondrial dysfunction in various pathological conditions. PINK1, a Parkinson's disease (PD) associated gene, plays key roles in maintaining mitochondrial function and integrity. In Drosophila melanogaster, deficiency of PINK1 results in PD-like pathologies due to mitochondrial abnormalities. Here, we report the existence of a new type of mitochondrial-membrane deformity, mitochondrial spherical compartmentation (MSC), caused by PINK1 deficiency in Drosophila. The MSC is a three-dimensional spheroid-like mitochondrial membrane structure encompassing nonselective contents. Upregulation of dDrp1, downregulation of dMarf, and upregulation of dArgK1-A—all resulting in mitochondrial fragmentation—were able to suppress the formation of MSC. Furthermore, arginine kinase, only when localizing to the vicinity of mitochondria, induced mitochondrial fragmentation and reversed the MSC phenotype. In summary, this study demonstrates that loss of dPINK1 leads to the formation of mitochondrial-membrane deformity MSC, which responds to mitochondrial dynamics. In addition, our data suggest a new perspective of how phosphagen energy-buffer system might regulate mitochondrial dynamics.

Constraints from the Ntaba Mhlope Syncline and the Mkomozane Homocline, Moodies Group (3.22 Ga), Eswatini, on the deformation of the southern margin of the Barberton greenstone belt

The Barberton Greenstone Belt (BGB) has been classically thought to be a first-order synclinal structure, therefore constraining vertically-dominated models of early Earth lithosphere (de-)formation. Geological mapping, strain analysis, U-Pb zircon age dating, and Raman spectroscopy of carbonaceous matter (RSCM) of the Ntaba Mhlope Syncline (NMS) and the Mkomozane Homocline (MH) close to the southeastern linear margin of the BGB in Eswatini assess this interpretation by constraining the type and timing of the dominant late-phase deformation in this region. Geologic mapping shows that the NMS is a steeply doubly plunging, highly strained syncline composed of basal Moodies conglomerates overlain by sandstones and subordinate shales and siltstones. Deformation of conglomerate clasts is markedly constrictional and of uniform orientation throughout the syncline, suggesting that regional deformation occurred in zones of ductile strain. RSCM indicates maximum peak paleotemperatures of ca. 500 °C, somewhat elevated compared to temperatures measured throughout the BGB. Shortening may have occurred contemporaneously with lower crustal extension.

Change in the Radius of the First Coordination Sphere in Amorphous Alloys during Deformation

Changes in the structure of amorphous alloys under deformation by high-pressure torsion, multiple-pass rolling, and pressure treatment have been studied using X-ray diffraction and scanning electron microscopy. It has been shown that under all types of deformation, shear bands are formed in amorphous alloys, which are regions of lower density compared to a surrounding undeformed amorphous matrix. Shear bands are regions of an increased free volume; the formation of bands results in steps occurring on the surface of samples. The number of shear bands and the surface morphology of deformed amorphous alloys are determined by the deformation type and physical properties of a material.

An adjoint-based drag reduction technique for unsteady flows

A framework based on a continuous adjoint-based analysis of steady and unsteady flows to predict and control the drag force due to surface morphing is presented. By establishing a relation between perturbations in the body shape and in the boundary condition on a certain geometry, we derive an analytical expression of the sensitivity to changes in the geometry of the body and its relation to the sensitivity to the perturbation of the boundary conditions. The methodology is evaluated on the incompressible flow around a cylinder for steady and unsteady flows. A reduction of the drag coefficient was obtained and investigated by several surface deformations, conducted in the direction of the sensitivity vector field obtained by solving the derived adjoint problem. In unsteady flows, the sensitivity field is computed by integrating the unsteady adjoint problem backward in time from the unsteady flow solution. Two different types of deformations based on the calculated sensitivity were applied: time-averaged deformation and time-dependent. Attempting the latter, a deformation at each time step, did not yield the same satisfactory results as the time-averaged in terms of expected drag reduction. We provide a theoretical reasoning for the difference between both methodologies, together with an insight into the physics of the sensitivity vector field distribution relating it to the drag force sources.

Influence of Deformation of Metal Matrix on the Mechanical Properties of Poly(Ethylene Terephthalate) Inside It

The influence of different types of deformation of the metal matrix on mechanical behavior of the amorphous PET film upon its transverse compression in the ductile metal matrix has been investigated. Three deformation modes have been probed. In the first case, a disc-shaped polymer specimen has been put between two 5 mm thick discs of the lead–tin alloy and squeezed in the press. In the second and the third cases, planar elongation has been performed in the so called “dead channel”, i.e., the channel with fixed side walls, the film being elongated due to decrease in the width or thickness, respectively. The plots of true yield stress at different draw ratios have formed a common master curve. At high total draw ratio Λ, the true yield stresses have been close for the considered three types of drawing in the metal. At the draw ratio Λ 2.6, the neck has not appeared, and the specimen has been deformed uniformly. When the film in the channel is elongated due to the decrease in thickness at constant width, the specimen width has been mainly decreased during subsequent elongation in the testing machine. When the film in the channel is elongated due to the decrease in width at constant thickness, further elongation has mainly led to the decrease in the specimen thickness. The true stress Σ has been expressed as Σ = Σ0 + KΛ3, with K being a constant. Deformation of the polymer in the channel occurred with the formation of shear bands. At the preliminary draw ratio Λ = 1.82, the bands have been oriented at the angle 21.5° with respect to the stretching axis. The planar elongation has led to abnormally strong deformation softening of the polymer. The drawing has been accompanied by an increase in the elasticity modulus of the polymer. The obtained results have suggested that the macromolecules orientation is the main reason for strain hardening of the polymer.

Electric-field-controlled deformation and spheroidization of compound droplet in an extensional flow

A 3-dimensional numerical model is developed by employing the electric current model and the phase-field method to investigate the electric-field-mediated compound droplet deformation and spheroidization in an extensional flow field (EFF). Based on this model, the detailed deformation morphologies of the compound droplet under different electrophysical properties are presented and the underlying electrohydrodynamics are clarified. Furthermore, the regime diagrams for quantificationally identifying different droplet deformation characteristics are summarized. In particular, the quantitative electrohydrodynamic criterion is obtained for achieving the droplet spheroidization in an EFF via the active electric field (EF) regulation. It is found that by applying a proper EF, the hydrodynamic force imposed by the EFF on the compound droplet and the flow-field-induced morphology deformation can be completely counterweighted. The deformation types and degrees of the compound droplet are determined by the fluids’ electrophysical parameters (especially the conductivity ratio R01 and permittivity ratio S01), EFF strength, and EF strength. Within the current research scope, the compound droplet can be restored to a spherical shape only when R01S01>1. Specifically, under a proper R01S01 (7≤ R01S01≤10 in the current simulation), the changing rate of the deformation of the outer droplet and inner droplet can match exactly and the two droplets can reach a spherical shape (i.e., S-S shape) simultaneously. Furthermore, the critical electric capillary number (CaE) for the compound droplet spheroidization is almost linearly related to the capillary number (Ca), which can be expressed as CaE=kCa. The factor k decreases with an increasing R01S01, so a larger R01S01 helps the compound droplet maintain its spherical shape.

Largest Lyapunov exponent as a tool for detecting relative changes in the particle positions.

Dynamics of the driven Frenkel-Kontorova model with asymmetric deformable substrate potential is examined by analyzing response function, the largest Lyapunov exponent, and Poincaré sectionsfor two neighboring particles. The obtained results show that the largest Lyapunov exponent, besides being used for investigating integral quantities, can be used for detecting microchanges in chain configuration of both damped Frenkel-Kontorova model with inertial term and its strictly overdamped limit. Slight changes in relative positions of the particles are registered through jumps of the largest Lyapunov exponent in the pinning regime. The occurrence of such jumps is highly dependent on type of commensurate structure and deformation of substrate potential. The obtained results also show that the minimal force required to initiate collective motion of the chain is not dependent on the number of Lyapunov exponent jumps in the pinning regime. These jumps are also registered in the sliding regime, where they are a consequence of a more complex structure of largest Lyapunov exponent on the step.

Families and unfoldings of singular holomorphic Lie Algebroids

In this paper, we investigate families of singular holomorphic Lie algebroids on complex analytic spaces. We introduce and study a special type of deformation called unfoldings of Lie algebroids, which generalizes the theory of singular holomorphic foliations developed by T. Suwa. We show that a one to one correspondence between transversal unfoldings and holomorphic flat connections on a natural Lie algebroid on the bases exists.