Inflation Tests Research Articles

Mechanical properties of stromal striae, and their impact on corneal tissue behavior

Cornea is an essential element of our eye. The refractive power of the cornea is closely related to its shape, which depends on the balance between its mechanical properties and the intraocular pressure. However, in keratoconus, the shape of the cornea is altered, and the mechanical properties (i.e., elastic modulus and viscosity) are reduced. These alterations have been associated with the development of striae within the cornea. Recently, such striae have been observed in healthy corneas as well, but with slightly different shapes. Our study investigated the mechanical role of these striae. To this end, we performed an inflation test under Optical Coherence Tomography: tomographic volumes were acquired in the central zone of eleven human corneas during an inflation test. Striae planes were extracted from the segmented images, and principal deformation maps were obtained by Digital Volume Correlation (DVC). We observe that the pattern of the striae does not change with pressure, even far above physiological pressure. Maximum principal strains are co-localized with the striae and are oriented perpendicular to the striae. We also observe that principal deformations on the striae increase with depth in the cornea. Our results show that striae lead to greater deformability in the direction perpendicular to the striae, especially in the posterior part of the cornea where they are the most visible. This supports the idea that the striae are undulations in the cornea collagenous microstructure, which are progressively unfolded under loading. They decrease the global stiffness of the cornea, in particular in the posterior part, and thus may help in accommodating deformations.

Biomechanical changes of tree shrew posterior sclera during experimental myopia, after retrobulbar vehicle injections, and crosslinking using genipin

Myopia is a common ocular condition characterized by biomechanical weakening revealed by increasing creep rate, cyclic softening scleral thinning, change of collagen fibril crimping, and excessive elongation of the posterior sclera resulting in blurred vision. Animal studies support scleral crosslinking as a potential treatment for myopia control by strengthening the weakened sclera and slowing scleral expansion. While multiple studies investigated aspects of the biomechanical weakening and strengthening effects in myopia and after scleral crosslinking, a comprehensive analysis of the underlying mechanical changes including the effect of vehicle injections is still missing. The purpose of this study was to provide a comprehensive analysis of biomechanical changes by scleral inflation testing in experimental myopia, after retrobulbar vehicle injections and scleral crosslinking using genipin in tree shrews. Our results suggest that biomechanical weakening in myopia involves an increased creep rate and higher strain levels at which collagen fibers uncrimp. Both weakening effects were reduced after scleral crosslinking using genipin at doses that were effective in slowing myopia progression. Vehicle injections increased mechanical hysteresis and had a small but significant effect on slowing myopia progression. Also, our results support scleral crosslinking as a potential treatment modality that can prevent or counteract scleral weakening effects in myopia. Furthermore, vehicle solutions may cause independent biomechanical effects, which should be considered when developing and evaluating scleral crosslinking procedures.

Testing scale-invariant inflation against cosmological data

There is solid theoretical and observational motivation behind the idea of scale-invariance as a fundamental symmetry of Nature. We consider a recently proposed classically scale-invariant inflationary model, quadratic in curvature and featuring a scalar field non-minimally coupled to gravity. We go beyond earlier analytical studies, which showed that the model predicts inflationary observables in qualitative agreement with data, by solving the full two-field dynamics of the system — this allows us to corroborate previous analytical findings and set robust constraints on the model's parameters using the latest Cosmic Microwave Background (CMB) data from Planck and BICEP/Keck. We demonstrate that scale-invariance constrains the two-field trajectory such that the effective dynamics are that of a single field, resulting in vanishing entropy perturbations and protecting the model from destabilization effects. We derive tight upper limits on the non-minimal coupling strength, excluding conformal coupling at high significance. By explicitly sampling over them, we demonstrate an overall insensitivity to initial conditions. We argue that the model predicts a minimal level of primordial tensor modes set by r ≳ 0.003, well within the reach of next-generation CMB experiments. These will therefore provide a litmus test of scale-invariant inflation, and we comment on the possibility of distinguishing the model from Starobinsky and α-attractor inflation. Overall, we argue that scale-invariant inflation is in excellent health, and possesses features which make it an interesting benchmark for tests of inflation from future CMB data.

Characterization of the interface fracture energy dependency on mixed mode fracture between rigid fiber and soft matrix

An enhanced version of the Rubber Cord Adhesion Inflation Test (RCAIT) has been designed to experimentally assess the internal pressure and cable tension applied to the specimen needed to propagate a crack along the matrix/reinforcement interface. To calculate the critical strain energy release rate, we develop a semi-analytical model describing the deformation of a hyperelastic tube under loading conditions that reflect the ones applied experimentally. A more comprehensive numerical model of the test is also proposed to investigate the influence of loading conditions on rubber deformation near the crack tip. Comparison of different experimental data sets with the theoretical/numerical data demonstrates that the new experimental setup allows for a reliable determination of the rubber/cord interface failure envelope under combined loading conditions.

Changes in the Biomechanical Properties of Corneal Stromal Lens after Collagen Crosslinking Induced by EDC-NHS.

To evaluate the changes of lens antidilatation, antiedema, and antienzymolysis ability after different concentrations of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and N-hydroxysuccinimide (EDC-NHS)-induced collagen cross-linking. Corneal stromal lenticules (n = 100) obtained from small incision lenticule extraction (SMILE) procedures were divided into 5 groups: no treatment (control); EDC/NHS (5%/2.5%); EDC/NHS(5%/5%); EDC/NHS (10%/5%); riboflavin and ultraviolet-A light (UVA). Collagen crosslinking was induced using EDC-NHS and UVA. Biomechanical assessments including inflation test, enzymatic degradation resistance, and light transmittance were evaluated posttreatment. (1) Lenticule apex displacement ranked: control Group > UVA Group > Group (5%/5%) > Group (5%/2.5%) > Group (10%/5%) (Friedman test, p < 0.0001). (2) Light transmittance was significantly higher in the crosslinked groups versus control, with EDC/NHS superior to UVA riboflavin. After 15 minutes in PBS, light transmittance decreased due to swelling; however, crosslinked groups maintained significantly higher transmittance versus control. (3) Following crosslinking, enzymatic resistance improved significantly, with the EDC-NHS crosslinking group was significantly better than the UVA cross-linking group. EDC/NHS crosslinking enhanced lenticule stiffness, antiedema, and enzymatic resistance and without compromising the transparency of the lens. Moreover, EDC/NHS crosslinking efficacy exceeded UVA riboflavin crosslinking in improving lenticule biomechanical properties.

Biomechanical and histological changes associated with riboflavin ultraviolet-A-induced CXL with different irradiances in young human corneal stroma

Keratoconus (KC) is a degenerative condition affecting the cornea, characterized by progressive thinning and bulging, which can ultimately result in serious visual impairment. The onset and progression of KC are closely tied to the gradual weakening of the cornea's biomechanical properties. KC progression can be prevented with corneal cross-linking (CXL), but this treatment has shortcomings, and evaluating its tissue stiffening effect is important for determining its efficacy. In this field, the shortage of human corneas has made it necessary for most previous studies to rely on animal corneas, which have different microstructure and may be affected differently from human corneas. In this research, we have used the lenticules obtained through small incision lenticule extraction (SMILE) surgeries as a source of human tissue to assess CXL. And to further improve the results' reliability, we used inflation testing, personalized finite element modeling, numerical optimization and histology microstructure analysis. These methods enabled determining the biomechanical and histological effects of CXL protocols involving different irradiation intensities of 3, 9, 18, and 30 mW/cm2, all delivering the same total energy dose of 5.4 J/cm2. The results showed that the CXL effect did not vary significantly with protocols using 3–18 mW/cm2 irradiance, but there was a significant efficacy drop with 30 mW/cm2 irradiance. This study validated the updated algorithm and provided guidance for corneal lenticule reuse and the effects of different CXL protocols on the biomechanical properties of the human corneal stroma.

Biomechanical Correlations Between the Cornea and the Optic Nerve Head.

A thin cornea is a potent risk factor for glaucoma. The underlying mechanisms remain unexplained. It has been postulated that central corneal thickness (CCT) may be a surrogate for biomechanical parameters of the posterior eye. In this study, we aimed to explore correlations of biomechanical responses between the cornea and the optic nerve head (ONH) and the peripapillary sclera (PPS) to elevated intraocular pressure (IOP), the primary risk factor of glaucoma. Inflation tests were performed in nine pairs of human donor globes. One eye of each pair was randomly assigned for cornea or posterior eye inflation. IOP was raised from 5 to 30 millimeters of mercury (mmHg) at 0.5 mmHg steps in the whole globe and the cornea or the ONH/PPS was imaged using a 50 MHz ultrasound probe. Correlation-based ultrasound speckle tracking was used to calculate tissue displacements and strains. Associations of radial, tangential, and shear strains at 30 mmHg between the cornea and the ONH or PPS were evaluated. Corneal shear strain was significantly correlated with ONH shear strain (R = 0.857, P = 0.003) and PPS shear strain (R = 0.724, P = 0.028). CCT was not correlated with any strains in the cornea, ONH, or PPS. Our results suggested that an eye that experiences a larger shear strain in the cornea would likely experience a larger shear strain in its ONH and PPS at IOP elevations. The strong correlation between the cornea's and the ONH's shear response to IOP provides new insights and suggests a plausible explanation of the cornea's connection to glaucoma risk.

Numerical Analysis of Mice Carotid Arteries’ Response Emphasizing the Importance of Material Law Constants’ Validation

In this paper, a detailed validation of the passive material properties of mice carotid arteries and constants of the Fung and Holzapfel hyperelastic material laws is conducted by means of static nonlinear FEM analyses. The response of the carotid arteries in an inflation test is studied here for the following mouse models: wild-type, mdx, sgcd−/−, Eln+/+, Eln+/−, Fbln5+/+, and Fbln5−/−. All FEM computations are conducted on models that have been preliminarily checked for their reliability. The results of the calculations, namely, the relation between the internal pressure and the artery outer diameter, are verified against experimental responses and the applicability of the laws is assessed. New sets of Holzapfel constitutive relation constants are proposed for Eln+/+ and Fbln5−/− mice. Finally, the problem of carotid artery buckling is also discussed. The buckling pressures of the arteries are predicted using FEM models and nonlinear static analyses. These values are compared with the reference experimental results, which allow for further validation of the constitutive relations. The research emphasizes that computations and numerical methods enable an accurate description of bioengineering processes and behaviors but only if the models used are appropriately validated.

A finite strain integral model for the creep behavior of vaginal tissue

Vaginal delivery causes significant stretching of the vagina and surrounding muscles, potentially leading to the development of pelvic floor disorders and other maternal morbidities. Despite the extended duration of labor, little experimental and theoretical work has been done to characterize the long-term viscoelastic behavior of vaginal tissue. To mathematically capture the creep response of rat vaginal tissue measured, this study presents a new anisotropic finite-strain constitutive model within the single integral Pipkin-Rogers viscoelastic framework. The constitutive parameters are computed by curve-fitting the model to strain versus time data collected from ex vivo inflation testing along the two primary anatomical directions of the vagina, the longitudinal and circumferential directions. The results showed good agreement between theory and experiments, suggesting that the proposed model could be used to advance our understanding of the time-dependent deformations that are experienced by the vagina during delivery. This modeling framework represents a first step toward the development of accurate computational tools that can predict the safety of vaginal deliveries, reducing unnecessary Cesarean sections and their related complications.

Testing multi-field inflation with LiteBIRD

We investigate expected constraints on the primordial tensor power spectrum from the future cosmic microwave background polarization experiment LiteBIRD as a test of multi-field inflation, where we specifically consider spectator models as representative examples. We argue that the measurements of the tensor-to-scalar ratio and the tensor spectral index, in combination with the constraints on the scalar spectral index from the Planck observation, are useful in testing multi-field inflation models. We also discuss implications for multi-field inflationary model building.

High-nitrogen azotetrazole based pyrogen gas generating propellants: Aspects on synthesis, characterization, combustion characteristics and kinetics

Propellant formulations containing a novel high nitrogen azotetrazole salt viz., diammonium 5,5′-azotetrazolate (DAAzT) along with two different binders viz., hydroxyl terminated polybutadiene (HTPB) and glycidyl azide polymer (GAP) were realized as potential pyrogen-based gas generators for use in inflatable structures. The DAAzT-GAP and DAAzT-HTPB propellant systems were investigated for their gas generating capabilities and it was found that the GAP based system offers enhanced gas yield of ∼430 mL/g against ∼320 mL/g for the HTPB based propellant at standard operating pressure of 1 bar and temperature of 298 K. Combustion product analyses of the propellant were undertaken by pyro GC–MS and it was found that the combustion products are benign and constitutes 62% and 53% N2 (mass fraction) as major combustion products from GAP and HTPB propellant respectively. A detailed thermal analysis of DAAzT by isoconversional method of Vzayovkin was undertaken and the dependence of activation energy with conversion was evaluated. The activation energy was also determined using a classical Kissinger method. The impact and friction sensitivity of the promising GAP-DAAzT propellant was found to be 3 Nm and 360 N respectively and the auto ignition temperature is 177.0 °C. Functional evaluation and gas generating capability of DAAzT-GAP propellant were successfully demonstrated in a sub-scale inflation test in a stand-alone configuration.

Rubber cord adhesion inflation test: Influence of envelope/confinement friction

The Rubber Cord Adhesion Inflation Test (RCAIT), has been previously introduced as an alternative test protocol to traditional pull-out tests for measuring the toughness of rubber matrix to metal reinforcement interfaces. A pressurized fluid is injected in between the matrix and reinforcement in a non-adherend region to initiate and propagate a crack along the specimen. A self-similar crack propagation regime hypothesis is assumed and the critical strain energy release rate is obtained from a simple energy balance analysis. However, to force the crack propagation along the specimen and prevent the development an aneurism in the rubber enveloppe, a confinement tube is used. A lubricant allows “free” longitudinal expansion of the rubber envelope during the contact. Combined theoretical, numerical, and experimental analyses are then proposed here to assess the effectiveness of lubrication conditions. Our results indicate an inversely proportional scaling between the elongation gradient and the friction coefficient in the pre-crack region. The observation confirms the validity of frictionless contact with a greased contact. Meanwhile, the steady-state crack growth assumption holds with the introduction of contact friction.

Development of a FEM procedure for evaluating the pressure profile in the industrial wheel and fatigue strength analyses

Industrial wheels are heavily loaded components that undergo severe cyclic stress conditions. Thus, the design of the rims must include a wide fatigue study which articulates in laboratory and field tests, analytical and numerical analyses and comparison of the experimental and computational results. This paper presents the study approach applied in the study of a 25 in rim for earth-moving machines manufactured by Moveero. The rim was subject to a design update which provided the reduction of the thickness from 11 mm to 9 mm. We decided to study the interaction tire-rim because it's a critical zone. The failures affected the area of the seat radius of the fixed flange of the rim, which resulted to be the most stressed part of the rim because of the bending actions of the tire on the flange. In order to deepen the cyclic mechanical behaviour of the component, laboratory inflation and rolling tests were carried out in Woodridge USA considering several combinations of inflation pressure and radial load applied to the wheel. The strain data from the tests were analysed to develop a reverse empirical model for the contact pressure between tire and rim. Once the load diagram applied to the flange for each test was estimated, FEM static simulations could be performed on a 3D model of the rim through SolidWorks Simulation. The stress fields obtained were then used for fatigue FEM numerical analyses which could return an evaluation of the predicted life of the component under several load conditions.

Study of the biomechanical response of a prosthetic mesh secured with penetrating and non-penetrating fixations in IPOM ventral hernia repair.

Sutures or tacks are commonly used to secure a mesh in intraperitoneal onlay mesh (IPOM) hernia repair, but such penetrating fixations can cause local damage, that can be associated with pain. The use of an adhesive could be an alternative to reduce complications. However, a risk associated with this approach has been identified, particularly when the defect cannot be closed. A mesh glued to the peritoneum only might not provide as much mechanical reinforcement to the abdominal wall (AW) as a mesh anchored to the myofascial structure with penetrating fixations, which could lead to an increased recurrence rate. Additionally, the high elasticity of the peritoneum may increase mesh bulging. Leveraging an ex vivo approach, the objective of this study was to investigate the impact of mesh fixation using glue versus barbed sutures, on its biomechanical response for IPOM surgery. An experimental method was developed using ex vivo porcine abdominal wall samples (n = 12). A 4-cm centered circular defect was created by dissecting the skin and the subcutaneous tissue and removing muscle and extraperitoneal fat, while keeping the peritoneum intact. A 14-cm diameter mesh was secured (Dermabond™ cyanoacrylate adhesive or V-Loc™ barbed sutures) to the AW. The mesh was placed on the peritoneum to remain consistent with the IPOM placement. The sample was then subjected to some inflation tests to simulate increased levels of intra-abdominal pressure (IAP) representing daily activities. For each test, mesh bulging into the defect was assessed as a function of the pressure using Digital Image Correlation (DIC) analysis. Mesh bulging was studied for 2 configurations: suture fixation and glue. Glued meshes exhibited significantly higher bulging values than when sutured with a significant difference (p = 0.013) observed at 252 mmHg and a certain trend for statistical difference (p < 0.1) for stair climbing or coughing activities. Additionally, the stiffness of the repair was also significantly higher when the mesh was sutured compared to when it was glued to the peritoneum (p < 0.05). This study demonstrated that a mesh glued to the peritoneum exhibited higher bulging and a behavior of the repair less stiff compared to when it was sutured to the myofascial structure of the AW, particularly for high intra-abdominal pressures. However, the impact of these differences remains to be evaluated over time. Further preclinical investigations are needed to quantify their impact post-operatively.

A numerical comparison of simplified Galerkin and machine learning reduced order models for vaginal deformations

High-fidelity computer simulations of childbirth remain prohibitively expensive and time consuming, making them impractical for guiding decision-making during obstetric emergencies. Cheap computer simulations that preserve the accuracy of high-fidelity models can be developed using surrogate modeling. Two common approaches to surrogate modeling are physics-based reduced order modeling (ROM) and machine learning (ML), with the latter gaining popularity as the scientific computing community seeks to leverage advances from other, mostly non-physics-based, computational strategies. Although ROM and ML have been compared for various problems, to our knowledge, such a comparison for simulations of vaginal deformations is currently missing. This study provides a baseline numerical comparison between methods from these two fundamentally different approaches. Since there are many methods falling into each modeling approach, to provide a fair and natural comparison, we select a basic model from each category, with each allowing (i) a straightforward implementation in commercial software packages, and (ii) use by practitioners with limited experience in the field. As a benchmark for the numerical comparison of the ROM and ML approaches, we use the finite element (FE) modeling of the ex vivo deformations of rat vaginal tissue subjected to inflation testing to study the effect of a pre-imposed tear. From the ROM strategies, we consider a simplified Galerkin ROM (G-ROM) that is based on the linearization of the underlying nonlinear equations. From the ML strategies, we select a feed-forward neural network to create mappings from constitutive model parameters and luminal pressure values to either the FE displacement history (in which case we denote the resulting model ML) or the proper orthogonal decomposition (POD) coefficients of the displacement history (in which case we denote the resulting model POD-ML). The numerical investigation of G-ROM, ML, and POD-ML takes place in the reconstructive regime. The numerical results show that the G-ROM outperforms the ML model in terms of offline central processing unit (CPU) time for model training, online CPU time required to generate approximations, and relative error with respect to the FE models. The G-ROM achieves superior error performance to the best ML model with 11 POD basis functions. With higher-dimensional POD bases, the G-ROM achieves a relative error 3 orders of magnitude lower than that of the best ML model with an online CPU time still on the same order of magnitude as the best ML model. The POD-ML model improves on the speed performance of the ML, having online CPU times comparable to those of the G-ROM given the same size of POD bases. However, the POD-ML model does not improve on the error performance of the ML and is still outperformed by the G-ROM for POD bases of size greater than 11. This baseline numerical investigation serves as a starting point for future computer simulations that consider state-of-the-art G-ROM and ML strategies, and the in vivo geometry, boundary conditions, and material properties of the human vagina, as well as their changes during labor.

A model for residually stressed viscoelastic bodies and its application to some boundary value problems

A model for residually stressed viscoelastic bodies undergoing finite deformations is developed and applied to the study of time-dependent responses of spheres and cylinders to various stress and strain controlled tests. An approach based on the notion of natural configurations is employed. An appropriate free energy function is used, and a suitable dissipation function is adopted to obtain a constitutive model. This constitutive model is applied to the study of different boundary value problems of thick spheres and cylinders. The responses to various strain controlled tests are investigated, which includes the stress-relaxation test and a test for a time-dependent inflation–deflation cycle. Also, the response to creep test and step-stress test in thick viscoelastic spheres is investigated. Furthermore, the stretch-controlled responses of residually stressed viscoelastic cylinders to pure torsion and axial stretch are studied. Pure torsion involves an axial extension or compression known as the Poynting effect. The Poynting effect in residually stressed viscoelastic bodies, which does not appear to be studied in the literature, is investigated in detail here. It is noted that the magnitude of the angle of twist has a significant influence (sometimes involving a change of sign) on the observed Poynting effect.

The Impact of Green Advertising Practices Dimensions on Consumer Green Purchasing Behavior in Food Sector of Afghanistan

Afghanistan faces pressing environmental issues such as deforestation, pollution, and soil degradation. Limited awareness of eco-friendly practices worsens these problems, necessitating a study on people's attitudes toward the environment. Additionally, Afghanistan is susceptible to climate change's adverse effects, including more frequent floods and droughts. Research can identify effective strategies to combat climate change through green practices, benefiting public health and the economy for a sustainable future. This research, grounded in the theory of planned behavior, examines the influence of green products and environmental awareness on consumers' eco-friendly purchasing habits. It also explores how environmental concerns impact the relationship between green products, awareness, and purchasing behavior. Statistical tools like regression, correlation, and variance inflation tests were employed to analyze data from 249 respondents using SPSS, confirming that green products play a pivotal role in shaping consumers' eco-friendly purchases. The study contributes in three significant ways: firstly, it bridges a gap in the literature by connecting environmental awareness, green products, and consumer behavior. Secondly, it empirically introduces environmental concerns as a contextual or moderating variable. Lastly, the study offers a unique perspective by focusing on Afghanistan. Practitioners can find valuable insights in this research, highlighting the importance of green awareness, environmental concerns, and eco-friendly consumer behavior.

The Influence of Inflation on the Consumption of Chinese Residents

China's inflation rate fluctuation is higher than that of developed countries in the same period, while the world has achieved remarkable economic development. With the economic growth and the increase of income, the problem of income inequality in China has become increasingly prominent. The polarization between rich and poor will affect social stability and become a huge resistance to building a well-off society in an all-round way. Exploring the relationship between inflation and income inequality, and proposing targeted measures to reduce the income gap, is of great practical significance for China to deepen reform and enhance people's sense of happiness and gain. China's economy has also been affected by imported inflation in the context of the global epidemic. This paper will analyze the basic theory of inflation and related effects, and focus on its impact on China's macroeconomic consequences. This paper uses the swot analysis method to analyze the current inflation test in China from the negative and positive effects, threats and opportunities, and interpret the relevant policies of China at the current stage and make a reasonable forecast of the future inflation trend.

Simulation of fluid driven crack propagation along metal/elastomer interface - Application to the numerical analysis of the rubber cord adhesion inflation test

The Rubber Cord Adhesion Inflation Test (RCAIT) has been proposed as an alternative technique to more standard pull out protocols such as H, T or pull out tests for characterizing the adhesion between cord/cable reinforcement and rubber. During this test, a fluid is injected in between a wire and a rubber cylindrical envelope to provoke the interface separation once a critical pressure is reached. A simple energy balance analysis is used to evaluate the critical strain energy release rate, GC, which drives the crack propagation from measurable quantities. However, some assumptions should be assessed to ensure reliable GC evaluation. Then, a predictive finite elements simulation of the RCAIT is proposed to simulate the fluid driven crack nucleation and propagation process along the rubber cord interface. These results are compared with the ones obtained from the RCAIT simplified analysis.

Computational study of the mechanical behavior of the astrocyte network and axonal compartments in the mouse optic nerve head.

Glaucoma is a blinding disease characterized by the degeneration of the retinal ganglion cell (RGC) axons at the optic nerve head (ONH). A major risk factor for glaucoma is the intraocular pressure (IOP). However, it is currently impossible to measure the IOP-induced mechanical response of the axons of the ONH. The objective of this study was to develop a computational modeling method to estimate the IOP-induced strains and stresses in the axonal compartments in the mouse astrocytic lamina (AL) of the ONH, and to investigate the effect of the structural features on the mechanical behavior. We developed experimentally informed finite element (FE) models of six mouse ALs to investigate the effect of structure on the strain responses of the astrocyte network and axonal compartments to pressure elevation. The specimen-specific geometries of the FE models were reconstructed from confocal fluorescent images of cryosections of the mouse AL acquired in a previous study that measured the structural features of the astrocytic processes and axonal compartments. The displacement fields obtained from digital volume correlation in prior inflation tests of the mouse AL were used to determine the displacement boundary conditions of the FE models. We then applied Gaussian process regression to analyze the effects of the structural features on the strain outcomes simulated for the axonal compartments. The axonal compartments experienced, on average, 6 times higher maximum principal strain but 1800 times lower maximum principal stress compared to those experienced by the astrocyte processes. The strains experienced by the axonal compartments were most sensitive to variations in the area of the axonal compartments. Larger axonal compartments that were more vertically aligned, closer to the AL center, and with lower local actin area fraction had higher strains. Understanding the factors affecting the deformation in the axonal compartments will provide insights into mechanisms of glaucomatous axonal damage.