surface curvature

Self-assembled quantum dots (QDs) are potential candidates for photoelectric and photovoltaic devices, because of their discrete energy levels. The characterization of QDs at the atomic level using a multimodal approach is crucial to improving device performance because QDs are nanostructures with highly correlated structural parameters. In this study, scanning transmission electron microscopy, geometric phase analysis, and atom probe tomography were employed to characterize structural parameters such as the shape, strain, and composition of self-assembled InAs-QDs with InGaAlAs spacer layers...

Molecules with curved architecture can exhibit unique opto-electronic properties due to the concave-convex π-surface. However, synthesizing negatively curved saddle-shaped aromatic systems has been challenging due to the internal structural strain. Herein, we report the facile synthesis of two polyhexagonal molecular systems, 1 and 2, with saddle shape geometry by judiciously varying the aromatic moiety, avoiding the harsh synthetic methods as that of heptagonal aromatic saddle systems. The unique geometry preferences of B, N, and S furnish suitable curvature to the molecules, featuring saddle shape...

INTRODUCTION: This systematic review aimed to compare reciprocating with continuous rotary instrumentation kinematics, by means of microcomputed tomography evaluations, in extracted human permanent teeth with moderate and severe canal curvatures. METHODS: The research protocol was registered in the International Prospective Register of Systematic Reviews and given the reference number CRD42023404035. An electronic search was undertaken in MEDLINE (PubMed), EBSCO, Scopus, Web of Science databases until December 2021...

Lipid packing defects are known to serve as quantitative indicators for protein binding to lipid membranes. This paper presents a protocol for mapping molecular lipid detail onto a triangulated continuum leaflet representation. Besides establishing the desired forward counterpart to the existing inverse TS2CG map, this coarse-grained to triangulated surface (CG2TS) map enables straightforward extraction of the defect characteristics for any membrane geometry found in nature. We have applied our protocol to investigate the role of local curvature and varying lipid packing on the defect constant π...

Under water, on land, or in the air, creatures use a variety of grasping methods to hunt, avoid predators, or carry food. Numerous studies have been conducted to construct a bionic surface for grasping tasks. This paper reviews the typical biomimetic structures and surfaces (wedge-shaped surface, suction cup surface and thorn claw surface) for grasping scenarios. Initially, progress in gecko-inspired wedge-shaped adhesive surfaces is reviewed, encompassing the underlying mechanisms that involve tuning the contact area and peeling behavior...

INTRODUCTION: Corneal ectasia leads to progressive irregular corneal curvature and reduced visual acuity. OBJECTIVE: To assess the safety and effectiveness of corneal collagen cross-linking (CXL) for managing corneal ectasia resulting from refractive laser surgery (RSL). METHODS: A systematic review and meta-analysis were realized according to PRISMA guidelines. We searched PubMed, EMBASE, Cochrane, and Web of Science databases for studies on CXL in patients with ectasia after RLS...

There are many instances of hollow-structure morphogenesis in the development of tissues. Thus, the fabrication of hollow structures in a simple, high-throughput and homogeneous manner with proper natural biomaterial combination is valuable for developmental studies and tissue engineering, while it is a significant challenge in biofabrication field. We present a novel method for the fabrication of a hollow cell module using a coaxial co-flow capillary microfluidic device. Sacrificial gelatin laden with cells in the inner layer and GelMa in the outer layer are used via a coaxial co-flow capillary microfluidic device to produce homogenous micro-beads...

Layered double hydroxides nanoparticles (LDH-NP) are increasingly studied for biomedical applications. Nevertheless, their interaction with biomolecules such as proteins needs further exploration for an effective application. In this work, the adsorption of bovine serum albumin (BSA) on LDH-NP and the conformation changes of the protein upon adsorption were characterized using fluorescence spectroscopy. First, the quenching of tryptophan residues of BSA by chloride-intercalated LDH-NP was explored and the BSA adsorption capacity of LDH-NP were determined...

We find a closed-form expression for the Poisson's coefficient of curved-crease variants of the "Miura ori" origami tessellation. This is done by explicitly constructing a continuous one-parameter family of isometric piecewise-smooth surfaces that describes the action of folding out of a reference state. The response of the tessellations in bending is investigated as well: using a numerical convergence scheme, the effective normal curvatures under infinitesimal bending are found to occur in a ratio equal and opposite to the Poisson's coefficient...

An exact equation for determining the Tolman length (TL) as a function of radius is obtained within the framework of classical thermodynamics and a computational procedure for solving it is proposed. As a result of implementing this procedure, the dependences of the TL and surface tension on radius are obtained for the drop and bubble cases and various equations of state. As one of the results of the thermodynamic study, a new equation for the dependence of surface tension on radius (curvature effect) alternative to the corresponding Tolman equation and associated with the spinodal point is obtained...

The performance of nano- and micro-porous materials in capturing and releasing fluids, such as during CO2 geo-storage and water/gas removal in fuel cells and electrolyzers, is determined by their wettability in contact with the solid. However, accurately characterizing wettability is challenging due to spatial variations in dynamic forces, chemical heterogeneity, and surface roughness. In situ measurements can potentially measure wettability locally as a contact angle - the angle a denser phase (e.g water) contacts solid in the presence of a second phase (e...

Biological membranes are integral cellular structures that can be curved into various geometries. These curved structures are abundant in cells as they are essential for various physiological processes. However, curved membranes are inherently unstable, especially on nanometer length scales. To stabilize curved membranes, cells can utilize proteins that sense and generate membrane curvature. In this review, we summarize recent research that has advanced our understanding of interactions between proteins and curved membrane surfaces, as well as work that has expanded our ability to study curvature sensing and generation...

Laser ultrasound is a widely used tool for industrial quality assurance when a contactless and fast method is required. In this work, we used a laboratory setup based on a confocal Fabry-Perot interferometer to examine weld seam models. The focus was placed on small samples with curved surfaces (small in the sense that the radius of curvature is comparable to the largest ultrasonic wavelength) and on efficient ways to detect the presence and volume of process pores, with the goal to transfer this method to industrial applications...

PURPOSE: To quantitatively evaluate the morphological parameters of meibomian glands (MGs) and lipid layer thickness (LLT) in patients with keratoconus (KC). METHODS: In this prospective, cross-sectional study, 164 eyes of 164 keratoconus patients and 64 eyes of 64 age-matched control subjects were included. An advanced automatic MG analyzer was used to quantitatively measure the morphological and functional parameters of MGs. Morphological and functional parameters of MGs, LLT, and other ocular surface parameters were compared between the control and KC groups...

The triply periodic minimal surface (TPMS) is a highly useful structure for bone tissue engineering owing to its nearly nonexistent average surface curvature, high surface area-to-volume ratio, and exceptional mechanical energy absorption properties. However, limited literature is available regarding bionic zirconia implants using the TPMS structure for bone regeneration. Herein, we employed the digital light processing (DLP) technology to fabricate four types of zirconia-based TPMS structures: P-cell, S14, IWP, and Gyroid...

Ion channel probes, as one of the ion channel platforms, provide an appealing opportunity to perform localized detection with a high precision level. These probes come basically in two classes: glass and metal. While the glass-based probes showed the potential to be employed for molecular sensing and chemical imaging, these probes still suffer from limited resolution and lack of control over protein insertion. On the other hand, metal-based nanoneedle probes (gold and silver) have been recently developed to allow reducing probe dimensions to the nanoscale geometry...

BACKGROUND: Amla (Emblica officinalis) is one of the most prominent fruits in terms of nutritional and medicinal properties and is utilized for the preparation of many traditional processed foods and in Ayurvedic formulations. OBJECTIVE: This study aims to investigate the enzyme activity and physical and chemical quality parameters during the growth and development stages of amla fruit for the determination of proper harvesting time to get optimum nutrient contents of fruit...

Bone can adapt its microstructure to mechanical loads through mechanoregulation of the (re)modeling process. This process has been investigated in vivo using time-lapsed micro-computed tomography (micro-CT) and micro-finite element (FE) analysis using surface-based methods, which are highly influenced by surface curvature. Consequently, when trying to investigate mechanoregulation in tissue engineered bone constructs, their concave surfaces make the detection of mechanoregulation impossible when using surface-based methods...

Cells often migrate on curved surfaces inside the body, such as curved tissues, blood vessels, or highly curved protrusions of other cells. Recent in vitro experiments provide clear evidence that motile cells are affected by the curvature of the substrate on which they migrate, preferring certain curvatures to others, termed "curvotaxis." The origin and underlying mechanism that gives rise to this curvature sensitivity are not well understood. Here, we employ a "minimal cell" model which is composed of a vesicle that contains curved membrane protein complexes, that exert protrusive forces on the membrane (representing the pressure due to actin polymerization)...

In this work, we have evaluated the influence of temperature and pressure on the mechanism of furan oxidation by the OH radical. The stationary points on the potential energy surface were described at the M06-2X/aug-cc-pVTZ level of theory. In the kinetic treatment at the high-pressure limit (HPL), we have combined the multistructural canonical variational theory with multidimensional small-curvature tunneling corrections and long-range transition state theory. The system-specific quantum Rice-Ramsperger-Kassel theory was employed to estimate the pressure-dependent rate...