Morphometry and Morphology of the Acromion Process and Its Implications in Subacromial Impingement Syndrome.

Introduction Subacromial impingement syndrome (SIS) is a common shoulder disorder characterized by pain and limited range of motion in the shoulder joint. It is frequently attributed to the compression or impingement of the rotator cuff tendons and bursa between the humeral head and the acromion process of the scapula during arm elevation. Subacromial impingement syndrome may arise as a result of the morphology of the acromion process, a bony protrusion at the top of the scapula that is important in the biomechanics of the shoulder joint. In order to detect potential anatomical differences that can predispose people to subacromial impingement syndrome, medical professionals and researchers need to have a thorough understanding of the morphometry and morphology of the acromion process. Aims and objectives The aim of the present study was to measure the morphometric and morphological characteristics of the acromion process in dried human scapulae that belonged to the North Indian population. Materials and methods This was a cross-sectional study that was carried out on 120 undamaged adult human scapula, of which 52 belonged to the right side and 68 belonged to the left side. Our study focused on analyzing the morphology of the acromion process as well as determining its maximum length, maximum breadth, acromio-coracoid distance, acromio-glenoid distance, and thickness. A statistical analysis of the observed parameters was carried out using the chi-square test and independent t-test with the help of Statistical Package for the Social Sciences (SPSS, IBM Corp., Armonk, NY) 24.0. Statistical significance was set at 0.05 (if the P-value ≤ 0.05, it is significant). Results We observed that the quadrangular shape (51.67%) of the acromion process was most commonly reported in our study, while the tubular (9.99%) shape was the least common. The difference in the incidences of various shapes of the acromion process on the right and left sides of the scapula was found to be statistically significant (p-value ≤ 0.05). In this study, the curved or type II acromion process was the most common type (53.34%) observed, while the least common shape reported was the hooked type (18.33%). The average length of the right acromion process was 44.52±6.61 mm, and the left acromion process was 45.13±6.35 mm. For the breadth, the right acromion had an average value of 28.31±4.67 mm, while the left had an average of 28.34±4.92 mm. The thickness of the right acromion measured 7.10±1.73 mm, and the left acromion was 7.53±1.44 mm. The acromio-coracoid distance on the right side was 34.59 ± 6.47 mm, and the left side was 37.46±6.22 mm. The acromio-glenoid distance was measured to be 32.31±5.87 mm on the right side and 33.18±5.39 mm on the left side. Conclusions Planning and carrying out an acromioplasty require an understanding of the morphometric parameters of the acromion process. Although there is a paucity of research on its morphometric evaluation in the North Indian population, the surgeons would be able to use these data as a reference.

Anomalous elasticity in classical glass formers.

Amorphous solids under mechanical strains are prone to plastic responses. Recent work showed that in amorphous granular systems these plastic events, that are typically quadrupolar in nature, can screen the elastic response. When the density of the quadrupoles is high, the gradients of the quadrupole field act as emergent dipole sources, leading to qualitative changes in the mechanical response, as seen for example in the displacement field. In this paper we examine the effect of screening in classical glass formers. These are made of point particles that interact via binary forces. Both inverse power law forces and Lennard-Jones interactions are examined, and it is shown that in both cases the elastic response can be strongly screened, in agreement with the novel theory. The degree of deviation from classical elasticity theory is parametrized by a proposed measure that is shown to have a functional dependence on the amount of energy lost to plastic responses.

Variations in the Formation of the Median Nerve and Its Clinical Correlation.

Introduction:The median nerve is commonly formed by the fusion of two roots, i.e., the lateral root arises from the lateral cord and the medial root from the medial cord. These roots embrace the axillary artery (third part) and then unite with each other slightly below the level of pectoralis minor, just anterior or anterolateral to the axillary artery. It is associated with different variations like origin from more than two roots, splitting of the nerve and abnormal connections with neighbouring nerves like musculocutaneous or ulnar nerve. Objectives:To explore the different anatomical variations in the formation of the median nerve in the North Indian population. Material and methods:We studied different variations in the formation of the median nerve during routine dissection classes of the upper limb which was for the undergraduate medical students at the Department of Anatomy of Indira Gandhi Institute of Medical Sciences, Patna, Bihar, India. The present study was conducted on a total of 84 upper limbs, of 42 formalin-preserved cadavers, of which 28 belonged to males and 14 to females. Results:We observed several variations in the formation of the median nerve. Three roots contributed to the formation of the median nerve in 25% of male subjects, among which the third root arose from the lateral cord of the brachial plexus in 16.07% of cases, and from the musculocutaneous nerve in 8.93% of cases. In females, three roots were found in 21.42% of cases, among which the root arose from the lateral cord of the brachial plexus in 14.28% of cases and from the musculocutaneous nerve in 7.14% of cases. Four roots were found in 5.36% of male cases, while in females they were found in 7.14% of cases. The formation of the median nerve occurred in the arm in 11.91% of cases (8.33% belonging to males and 3.58% to females), while in the axilla, it is formed anterior to the axillary artery in 4.76% of cases (3.57% belonging to males and 1.19% to females), medial to the axillary artery in 2.38% of cases (1.19% were found in both male and female cadavers). We also observed an abnormal connection between the median nerve and musculocutaneous nerve in two upper extremities (2.38% of cases) in one male and one female cadaver and one upper extremity of a female cadaver (1.19% of cases) in which the median nerve is present lateral to the brachial artery at the level of the cubital fossa. Conclusion:The knowledge about variations in the formation of the median nerve is relevant to both anatomists and surgeons. It is useful during different surgical procedures around the axilla and also helps in reducing the failure rate of nerve blocks around the infraclavicular part of the brachial plexus during surgeries involving this area.

Morphometric Study of the Nutrient Foramen of the Humerus in the Population of Bihar.

INTRODUCTION:  Fracture or surgical intervention of fracture of the shaft of the humerus may cause injury to the nutrient artery leading to the nonunion or delayed union of the fracture. It is important to find the number and location of the nutrient artery. So the knowledge regarding the nutrient foramen helps to protect them during any operative procedure of the shaft of the humerus. The main objective of this study is to find out the number, location, and direction of the nutrient foramen of the humerus. MATERIALS AND METHODS: The study was conducted on 80 dried humeri of unknown gender obtained from Narayan Medical College, Sasaram, Bihar, India, and also from other medical colleges of Bihar. The number, location, and direction of nutrient foramen were observed. RESULTS: The majority of humeri showed one nutrient foramen, which was found in 91.25%, followed by 3.75% with double foramen and 1.25% with triple foramen. Nutrient foramen was absent in 3.75% of the humerus. The majority (89.02%) of nutrient foramen was found on the anteromedial surface followed by anterolateral (9.76%) and posterior surface (1.22%). The majority of nutrient foramen was found on the middle third (86.58%) of the shaft, followed by 13.42% on the distal third. No nutrient foramen was found on the proximal third of the humerus. All nutrient foramina were directed downward. CONCLUSION: The location of the nutrient foramen of the humerus was not constant; it may present on anteromedial, anterolateral, or posterior surfaces. Similarly, it may present on the middle or distal third of the shaft of the humerus. This study will help surgeons planning the surgical intervention of the shaft of the humerus, which will possibly reduce the chances of nonunion or delayed union.

Domestic violence, women's health, and the sustainable development goals: integrating global targets, India's national policies, and local responses.

Domestic violence (DV) is a serious public health concern, affecting women's health and well-being. An international governance framework, through the United Nations' Sustainable Development Goals and national policies in India have committed the country to attempt elimination of violence against women. Even so, efforts remain starkly inadequate for altering conditions under which women experience DV. This review paper aims to develop an evidence-based, integrated life cycle model to alter conditions that perpetuate DV and related vulnerabilities in society. The analyses identify and determine community-based innovative practices and policies. We propose a collaborative 'R5 model' to incorporate a multi-stage response to break the cycle of gendered vulnerability. The model identifies five stages of vulnerability in the lives of victims of violence: rescue, recovery, rehabilitation, resilience, and reform. This approach can result in promoting a proactive state-society engagement to uphold the rights and the welfare of women. We recommend the 'R5 model' to bridge the global SDG targets, national policies, and local practices.

Particles confined in arbitrary potentials with a class of finite-range repulsive interactions.

In this paper, we develop a large N field theory for a system of N classical particles in one dimension at thermal equilibrium. The particles are confined by an arbitrary external potential, V_{ex}(x), and repel each other via a class of pairwise interaction potentials V_{int}(r) (where r is distance between a pair of particles) such that V_{int}∼|r|^{-k} when r→0. We consider the case where every particle is interacting with d (finite-range parameter) number of particles to its left and right. Due to the intricate interplay between external confinement, pairwise repulsion, and entropy, the density exhibits markedly distinct behavior in three regimes k>0, k→0, and k<0. From this field theory, we compute analytically the average density profile for large N in these regimes. We show that the contribution from interaction dominates the collective behavior for k>0 and the entropy contribution dominates for k<0, and both contribute equivalently in the k→0 limit (finite-range log-gas). Given the fact that this family of systems is of broad relevance, our analytical findings are of paramount importance. These results are in excellent agreement with brute-force Monte Carlo simulations.

Slow coarsening in unstable liquid films under gravity on a disordered substrate.

We study the evolution of unstable liquid films via numerical solutions of the thin-film equation. The film is placed on a coated substrate with disorder. This is modeled by a random spatial variation of the relative value of the Hamaker constants for the substrate and coating. The free energy consists of (a) the van der Waals term for the substrate/coating interactions with the film and (b) a term due to gravity. This free energy admits a Maxwell double-tangent construction with two coexisting phases, i.e., "thin" and "thick" phases. In the absence of disorder, the film dewets by true morphological phase separation (MPS), i.e., the elimination of domain walls between the coexisting phases. The introduction of disorder may result in the trapping of these domain walls, with a drastic slowdown in growth kinetics. We present detailed numerical results in D=2 and D=3 to understand this slow coarsening, where D is the dimensionality of the liquid-film system.

Finite-range Coulomb gas models. I. Some analytical results.

Dyson has shown an equivalence between infinite-range Coulomb gas models and classical random matrix ensembles for the study of eigenvalue statistics. In this paper, we introduce finite-range Coulomb gas models as a generalization of the Dyson models with a finite range of eigenvalue interactions. As the range of interaction increases, there is a transition from Poisson statistics to classical random matrix statistics. These models yield distinct universality classes of random matrix ensembles. They also provide a theoretical framework to study banded random matrices, and dynamical systems the matrix representation of which can be written in the form of banded matrices.

Finite-range Coulomb gas models. II. Applications to quantum kicked rotors and banded random matrices.

In part I of this two-stage exposition [Pandey, Kumar, and Puri, preceding paper, Phys. Rev. E 101, 022217 (2020)10.1103/PhysRevE.101.022217], we introduced finite-range Coulomb gas (FRCG) models, and developed an integral-equation framework for their study. We obtained exact analytical results for d=0,1,2, where d denotes the range of eigenvalue interaction. We found that the integral-equation framework was not analytically tractable for higher values of d. In this paper, we develop a Monte Carlo (MC) technique to study FRCG models. Our MC simulations provide a solution of FRCG models for arbitrary d. We show that, as d increases, there is a transition from Poisson to Wigner-Dyson classical random matrix statistics. Thus FRCG models provide a route for transition from Poisson to Wigner-Dyson statistics. The analytical formulation obtained in part I, and MC techniques developed in this paper, are used to study banded random matrices (BRMs) and quantum kicked rotors (QKRs). We demonstrate that, for a BRM of bandwidth b and a QKR of chaos parameter α, the appropriate FRCG model has range d=b^{2}/N=α^{2}/N, for N→∞. Here, N is the dimensionality of the matrix in the BRM, and the evolution operator matrix in the QKR.

Localization in liquid phase separation: Coarsening and stable structures.

Dynamics of pattern formation in self-organizing systems subjected to spontaneous suppression of diffusion through a recently proposed source-sink-boundary templating technique is presented based on three-dimensional numerical simulations. This template disorder is introduced to divide the system into three different subregions, i.e., a source (outer subregion) at higher potential and a sink (inner subregion) region at a lower potential with the help of a boundary which is at the highest potential. The boundary allows only one-way diffusion from source to sink so diffusion stops completely whenever the sink is filled to its capacity. This technique was shown to be able to spontaneously form stable and complex patterns in the source and the sink parts. While the technique is applicable to any self-organizing or phase-separating system whenever certain conditions are met, a physically realizable system of liquid films supported on chemically heterogeneous substrates which self-organizes through morphological phase separation is chosen to study the dynamics. Free-energy functional of this system shows an asymmetric double-well potential and the Maxwell's double tangent construction on this free energy gives rise to two distinct and finite equilibrium phases. Disorder is introduced in the form of chemical heterogeneity to divide the whole system into different subregions each consisting of two equilibrium phases, thus enabling more finite equilibrium points in the same system. The dynamics uncovers two different pathways for stable localized structures, viz., the defect and the direct pathway. Thinner films are likely to favor the defect pathway whereby the equilibrium pattern forms after coarsening, whereas thicker films will predominantly choose the direct pathway of pattern formation by phase separation. The final localized structure is same irrespective of the chosen pathway. The dynamics also shows that the patterns formed in the inner subregion part can be seen as a result of "localization" and those formed in the outer subregion are due to arrested diffusion under geometric or curvature constraints. Simple measures of localization in terms of free energy and its constituents are also presented. The identification of localization in the above systems opens up the possibility of a systematic approach to create controlled structures at nano- and submicrometer scales with desired shape and size. These structures constitute new building blocks of advanced and tailored materials.

Coarsening Dynamics of True Morphological Phase Separation in Unstable Thin Films.

Unstable thin films can spontaneously phase separate into two equilibrium flat-film morphologies of different thicknesses under the influence of gravity or favorable combinations of apolar and polar excess intermolecular forces. Two distinct pathways and associated dynamics of this morphological phase separation are presented based on numerical simulations of the 2-D thin film equation. The two pathways are (1) the "direct pathway" whereby the thicker phase forms directly and concurrently with the thinner phase and (2) the "defect pathway" whereby the thicker phase forms by the coarsening of defects of intermediate thickness and appears much later than the thinner phase. The defect pathway is favored by films whose initial thickness lies closer to the thickness of the thinner phase. Both pathways show an initial power law decay with exponent -1/4 in time followed by a plateau in the number density of domains/defects. Thereafter, the defect pathway shows another universal power law decay with exponent -1/3 and ends with a logarithmic decay, which is specific to the d = 2 case as there is no interfacial curvature in d = 2. The direct pathway skips the second power law decay and goes directly to the logarithmic decay.

Coarsening and pattern formation during true morphological phase separation in unstable thin films under gravity.

We address in detail the problem of true morphological phase separation (MPS) in three-dimensional or (2+1)-dimensional unstable thin liquid films (>100nm) under the influence of gravity. The free-energy functionals of these films are asymmetric and show two points of common tangency, which facilitates the formation of two equilibrium phases. Three distinct patterns formed by relative preponderance of these phases are clearly identified in "true MPS". Asymmetricity induces two different pathways of pattern formation, viz., defect and direct pathway for true MPS. The pattern formation and phase-ordering dynamics have been studied using statistical measures such as structure factor, correlation function, and growth laws. In the late stage of coarsening, the system reaches into a scaling regime for both pathways, and the characteristic domain size follows the Lifshitz-Slyozov growth law [L(t)∼t^{1/3}]. However, for the defect pathway, there is a crossover of domain growth behavior from L(t)∼t^{1/4}→t^{1/3} in the dynamical scaling regime. We also underline the analogies and differences behind the mechanisms of MPS and true MPS in thin liquid films and generic spinodal phase separation in binary mixtures.

Finite-range Coulomb gas models of banded random matrices and quantum kicked rotors.

Dyson demonstrated an equivalence between infinite-range Coulomb gas models and classical random matrix ensembles for the study of eigenvalue statistics. We introduce finite-range Coulomb gas (FRCG) models via a Brownian matrix process, and study them analytically and by Monte Carlo simulations. These models yield new universality classes, and provide a theoretical framework for the study of banded random matrices (BRMs) and quantum kicked rotors (QKRs). We demonstrate that, for a BRM of bandwidth b and a QKR of chaos parameter α, the appropriate FRCG model has the effective range d=b^{2}/N=α^{2}/N, for large N matrix dimensionality. As d increases, there is a transition from Poisson to classical random matrix statistics.