Non-compressible hemorrhage is an unmet clinical challenge that accounts for high mortality in trauma. Rapid pressurized blood flows under impair the function and integrity of hemostatic agents adhesion bioadhesive sealants. Here, we report design performance bioinspired microstructured bioadhesives, formed with a macroporous tough xerogel infused functional liquids. The can rapidly absorb interfacial fluids such as whole promote clotting, while liquids facilitate bonding, sealing,...

The aerodynamic transfer of energy from glottal airflow to vocal fold tissue during phonation was explored using complementary synthetic and numerical models. model fabricated a flexible polyurethane rubber compound. size, shape, material properties were generally similar corresponding human characteristics. Regular, self-sustained oscillations achieved at frequency approximately 120 Hz. onset pressure 1.2 kPa. A two-dimensional finite element developed geometry definitions based on the...

Acoustic analogy methods are used as post-processing tools to predict aerodynamically generated sound from numerical solutions of unsteady flow. The Ffowcs Williams–Hawkings (FW–H) equation and related formulations, such Farassat’s Formulations 1 1A, among the commonly analogies because their relative low computation cost robustness. These formulations assume propagation waves in a medium at rest. present paper describes surface integral formulation based on convective wave equation, which...

Tropocollagen types I and III were simultaneously fibrilized in vitro, the differences between geometric mechanical properties of heterotypic fibrils with different mixing ratios tropocollagen to investigated. Transmission electron microscopy was used confirm simultaneous presence both within fibrils. The incorporation collagen caused be thinner a shorter D-banding than pure I. Hertzian contact model obtain elastic moduli from atomic force microscope indentation testing using volume...

Cell-laden scaffolds of architecture and mechanics that mimic those the host tissues are important for a wide range biomedical applications but remain challenging to bioprint. To address these challenges, we report new method called triggered micropore-forming bioprinting. The approach can yield cell-laden defined interconnected pores over sizes, encompassing many cell types. viscoelasticity bioprinted scaffold match biological be tuned independently porosity stiffness. also exhibits...

Abstract Most existing injectable hydrogels are non-porous, thereby lacking a microporous structure to promote cell ingrowth. Also, most do not effectively adhere the host tissue. The present study describes an double network hydrogel formed by combining two hyaluronic acid (HA) derivatives, namely dopamine grafted HA (DAHA) and methacrylated (HAMA). These constituents instantly form physically crosslinked through Fe 3+ -dopamine coordination, confer fast gelation, pore formation,...

The aerodynamic generation of sound during phonation was studied using direct numerical simulations the airflow and field in a rigid pipe with modulated orifice. Forced oscillations an imposed wall motion were considered, neglecting fluid–structure interactions. compressible, two-dimensional, axisymmetric form Navier–Stokes equations numerically integrated highly accurate finite difference methods. A moving grid used to model effects walls. geometry flow conditions selected approximate...

Abstract While collagen type I (Col-I) is commonly used as a structural component of biomaterials, III (Col-III), another fibril forming ubiquitous in many soft tissues, has not previously been used. In the present study, novel concept an injectable hydrogel with semi-interpenetrating polymeric networks heterotypic fibrils, tissue-specific Col-III to Col-I ratios, glycol-chitosan matrix was investigated. introduced hydrogel, inspired by its co-presence influence on fibrillogenesis terms...

Endoscopic sinus surgery poses unique training challenges due to complex and variable anatomy, the risk of major complications. We sought create provide validity evidence for a novel 3D-printed simulator nose paranasal sinuses.Sinonasal computed tomography (CT) images patient were imported into 3D visualization software. Segmentation bony soft tissue structures was then performed. The model printed using simulated bone materials. Rhinologists otolaryngology residents completed 6 prespecified...

Injectable hydrogels are increasingly used for in situ tissue regeneration and wound healing. Ideally, an injectable implant should promote the recruitment of cells from surrounding native allow to migrate freely as they generate a new extracellular matrix network. Nanocomposite such carbon nanotube (CNT)-loaded have been hypothesized cell migration relative unloaded ones. To investigate this, CNT-glycol chitosan were synthesized studied. Chemoattractant-induced was studied using modified...

Biological tissues hinge on blood perfusion and mechanical toughness to function. Injectable hydrogels that possess both high permeability have profound impacts regenerative medicine but remain a long-standing challenge. To address this issue, injectable, pore-forming double-network are fabricated by orchestrating stepwise gelation phase separation processes. The interconnected pores of the resulting enable direct medium through organ-sized matrices. amenable cell encapsulation delivery...

Reinforced extracellular matrix (ECM)-based hydrogels recapitulate several mechanical and biochemical features found in the tumor microenvironment (TME) vivo. While these gels retain critical structural bioactive molecules that promote cell–matrix interactivity, their properties tend toward viscous regime limiting ability to ordered characteristics when considered as architectured scaffolds. To overcome this limitation characteristic of pure ECM hydrogels, we present a composite material...

The results are described of the second part an ongoing study aimed at performing direct numerical simulations translaryngeal flows during phonation. use accurate schemes allows radiated sound to be calculated directly, without need for acoustic analogy models. goal is develop a better understanding this class flow, and basic generation mechanisms involved in In present study, effects subglottal pressure glottal oscillation frequency on near-field flow farfield were investigated. presence...

Three-way interactions between sound waves in the subglottal and supraglottal tracts, vibrations of vocal folds, laryngeal flow were investigated. Sound wave propagation was modeled using a reflection analog method. An effective single-degree-of-freedom model designed to vocal-fold vibrations. The effects orifice geometry changes on considered by enforcing time-varying discharge coefficient within Bernoulli model. resulting allowed for energy transfer from structural vibrations, an essential...

Large eddy simulations (LES) of subsonic turbulent jets, including the near-field flow and far-field sound radiation, were performed using two different subgrid-scale turbulence models. Two cases considered. As a validation case, predictions from Mach 0.9, Reynolds number 3.6 × 10 3 randomly forced jet performed. Both velocity statistics directivity found to be in excellent agreement with previous experimental data direct numerical simulation (DNS) results. The second case involved 0.4, 5 x...

Acoustic data has long been harvested in fundamental voice investigations since it is easily obtained using a microphone. However, acoustic signals alone do not reveal much about the complex interplay between sound waves, structural surface mechanical vibrations, and fluid flow involved phonation. Available high speed imaging techniques have over past ten years provided wealth of information deformation superior larynx during Time-resolved images inner structure deformable soft tissues are...

Hydrogel adhesion that can be easily modulated in magnitude, space, and time is desirable many emerging applications ranging from tissue engineering soft robotics to wearable devices. In synthetic materials, these complex behaviors are often achieved individually with mechanisms apparatus difficult integrate. Here, we report a universal strategy embody multifaceted programmability hydrogels. By designing the surface network topology of hydrogel, supramolecular linkages result contrasting...

Voice production involves sound generation by a confined jet flow through an orifice (the glottis) with time-varying area. Predictive models of speech are usually based on the so-called quasi-steady approximation. The rate is assumed to be same as sequence steady flows stationary orifices for wall geometries and boundary conditions that instantaneously match those dynamic, nonstationary problem. Either or pressure drop can then used calculate radiated using conventional acoustic radiation...

Numerical simulations of an impulsively started jet were performed in order to investigate the effects trailing instability on axisymmetric vortex ring formation. The predictions compared experimental results reported literature and recently published numerical results. total circulations found be good agreement with both presence a universal formation time scale was confirmed. also highlighted important interaction between which develops for large discharge times dynamics head ring. This...

In this paper, the performance of a prototype standing wave thermoacoustic cooler is optimized using an extremum seeking control (ESC) algorithm. A tunable Helmholtz resonator was developed for to change boundary condition tube. The volume changed by changing location piston on ball-screw assembly driven dc motor. Multiparameter ESC applied optimize cooling power via tuning both (piston location) and driving frequency. Experiments were conducted online optimization under fixed varying...