Shape Changes Research Articles

Light-Responsive Shape- and Color-Changing Block Copolymer Particles with Fast Switching Speed.

Polymer particles capable of dynamic shape changes in response to light have received substantial attention in the development of intelligent multifunctional materials. In this study, we develop a light-responsive block copolymer (BCP) particle system that exhibits fast and reversible shape and color transitions. The key molecular design is the integration of spiropyran photoacid (SPPA) molecules into the BCP particle system, which enables fast and dynamic transformations of polystyrene-b-poly(4-vinylpyridine) (PS-b-P4VP) particles in response to light. The SPPA photoisomerization, induced by 420 nm light irradiation, lowers the pH of the aqueous surroundings from 5.5 to 3.3. The protonated P4VP block substantially increases in domain size from 14 to 39 nm, resulting in significant elongation of the BCP particles (i.e., an increase in the aspect ratio (AR) of the particles from 1.8 to 3.4). Moreover, SPPA adsorbed onto the P4VP surface induces significant changes in the luminescent properties of the BCP particles via photoisomerization of SPPA. Notably, the BCP particles undergo fast, dynamic shape and color transitions within a period of 10 min, maintaining high reversibility over multiple light exposures. Functional dyes are selectively incorporated into different domains of the light-responsive BCP particles to achieve different ranges of color responses. Thus, this study showcases a light-responsive hydrogel display capable of reversible and multicolor photopatterning.

Mechanism of Plant Resistance to Insects, Weeds and Pathogens

Plants are primary producers and a food source for many heterotrophic phytophagous organisms. They are affected by different biotic and abiotic environmental stress. Insects, fungi, bacteria, viruses, nematodes, and other pests are biotic factors that significantly reduce crop productivity. Naturally, plants protect themselves from pest attacks by developing different morphological, structural, and biochemical defense mechanisms. However, our understanding of these defensive mechanisms is still limited. Hence, the objective of this paper is to review the mechanism of plant resistance to insects, weeds, and pathogens to know the relevant defense or resistance mechanisms of plants against pests. Many morphological characteristics contribute to plant resistance to insect pests. These include trichomes, surface waxes and hardness of plant tissues, thickening of cell walls and cuticles, the rapid proliferation of tissues, anatomical changes in plant organs, and color and shape of plant parts. The chemical composition of the host plant affects the behavior and adaptation of the herbivore and the host plant. These chemicals can be physiological inhibitors or nutritional deficiencies. Secondary metabolites are compounds that decrease the palatability of the plant tissues in which they are produced but have no effect on a plant's regular growth and development. Plants defend themselves against pathogens by a combination of weapons termed host resistance which is a structural and biochemical defense mechanism and they also defend from weeds by producing allelochemicals. Thus, plants have developed multiple resistance mechanisms to protect against pests. These resistance mechanisms could be an important tool for pest management by reducing the dose of chemicals used in pest control, resulting in a minimal effect of the chemicals on the environment. Also, these resistance mechanisms are compatible with other control methods that act as one of the components of integrated pest management methods to reduce the damage caused by pests.

A Semantic Web-Based Approach for Bat Trajectory Reconstruction With Human Keypoint Information

Restoring the trajectory of a bat from a table tennis match video is critical in analyzing a table tennis technique and conducting statistical analysis. However, directly bat location detection in each frame is challenging due to changing shapes caused by varying movement directions and speeds, leading to ambiguity. This paper develops a novel two-stage method. The first stage utilizes YOLO for bat detection in each frame, followed by filtering out erroneous candidate boxes. In the second stage, the authors use a temporal prediction model that integrating human keypoint information and interpolation to reconstruct a complete bat trajectory with minimal errors. The method's effectiveness and performance are evaluated on our video datasets. The evaluation results demonstrate that the proposed method outperforms traditional methods on precision performance metrics. The error screening algorithm improves precision score to nearly 1. In addition, the method has the recall score 22.3% higher than YOLO 's and also 1.4% higher than that of YOLO with cubic spline interpolation.

A Phase-Field Discrete Element Method to study chemo-mechanical coupling in granular materials

This paper presents an extension of the discrete element method using a phase-field formulation to incorporate grain shape and its evolution. The introduction of a phase variable enables an effective representation of grain geometry and facilitates the application of physical laws, such as chemo-mechanical couplings, for modeling shape changes. These physical laws are solved numerically using the finite element method coupled in a staggered scheme to the discrete element model. The efficacy of the proposed Phase-Field Discrete Element Model (PFDEM) is demonstrated through its ability to accurately capture the real grain shape in a material subjected to dissolution only and compute the stress evolution. It is then applied to model the phenomenon of pressure solution involving dissolution and precipitation in granular materials at the microscale and enables to reproduce the creep response observed experimentally. This framework contributes to the enhanced understanding and simulation of complex behaviors in granular materials and sedimentary rocks for many geological processes like diagenesis or earthquake nucleation.

Pupil Data Upon Stimulation by Auditory Stimuli

Evaluating hearing in newborns and uncooperative patients can pose a considerable challenge. One potential solution might be to employ the Pupil Dilation Response (PDR) as an objective physiological metric. In this dataset descriptor paper, we present a collection of data showing changes in pupil dimension and shape upon presentation of auditory stimuli. In particular, we collected pupil data from 16 subjects, with no known hearing loss, upon different lighting conditions, measured in response to a series of 60–100 audible tones, all of the same frequency and amplitude, which may serve to further investigate any relationship between hearing capabilities and PDRs.

Three-dimensional deviation analysis and digital visualization of shape change before and after conservation treatment of historic kiln site

The Gangjin Celadon Kiln, after its excavation in 1982, was relocated and restored in 1987 and subjected to primary conservation treatment in 2007. However, many problems such as soil disintegration and cavitation occurred in the kiln until recently. In this study, the shape changes due to the conservation treatment in 2020, which was performed to maintain the original shape of the kiln site, were recorded via three-dimensional (3D) scanning, and numerical analysis was conducted to ensure continuous monitoring and preventive conservation. From the results of this study, the locations and ranges of shape changes before and after the conservation treatment of the kiln site were identified through root-mean-square (RMS) deviation analysis and visualization, and the ranges of reinforcement and soil mulch removal were quantified through the deviations at different points. In particular, the most noticeable shape changes occurring from the conservation treatment on the kiln site with 11.2 m long and 16.7° slope were around 15 mm, and many relative changes of 40 mm or more were also observed. In addition, a reinforcement of approximately 40 mm thickness at the least and a flattening were prominently evident on the floor of the working space; the inside of the combustion chamber was visualized with a reinforcement of at least about 50 mm. Damage caused by natural or artificial factors is expected because two extensive conservation treatments were applied in 2007 and 2020 to the kiln sites. Therefore, short-term monitoring using periodic 3D scanning and time-series data comparisons is necessary for the identification of the point of shape change and the determination of major damaged areas so that a mid- to long-term monitoring plan can be established based on the findings of such observations. In addition, predictive modeling research is mandated to detect areas in the entire kiln site that exhibit a greater probability of deterioration based on the available shape change data.

Synchronously Thermochromic and Shape‐Shifting Liquid Crystal Elastomers Enabled by Hierarchical Structure Control for Multidimensional Encryption

AbstractTo date, a diverse array of smart materials, drawing inspiration from nature, is developed, exhibiting remarkable shape or color‐changing capabilities, which hold great promise in applications such as bionic soft robots and information encryption platforms. Achieving reversible shape‐shifting and color variation harmoniously within a single material is a particularly appealing prospect. Herein, a facile approach to creating such materials is presented, capable of undergoing reversible shape and color‐change synchronously. This is achieved by harnessing the stress‐free two‐way shape‐memory effect (2W‐SME) of a liquid crystal elastomer (LCE), meticulously programmed at both macro and micro scales. Specifically, the LCE with stress‐free 2W‐SME is fabricated, and permanent grating nanostructures are meticulously constructed through UV‐assisted nanoimprinting. By enabling reversible shape alterations at multiple dimensions, encompassing both macro and micro scales, the LCE material concurrently exhibits reversible changes in shape and color, triggered by heat. As a result, intelligent information encryption and decryption platforms that leverage the unique capabilities of LCE are demonstrated. The outcomes of this research endeavor are poised to pave the way for the advancement of smart materials in the realms of data storage and encryption.

Enhancing gust load alleviation performance in an optimized composite wing using passive wingtip devices: Folding and Twist approaches

This paper introduces an innovative numerical method for the design and optimization of high-aspect-ratio composite wings equipped with passive control systems, specifically, Folding WingTip (FWT) and Twist WingTip (TWT) devices. The aim is to enhance Gust Load Alleviation (GLA) performance in the baseline wing. Recent numerical studies have indicated that the inclusion of spring devices and wingtip modifications can offer additional benefits in alleviating gust loads during flight. The baseline wing is designed using a comprehensive multi-disciplinary optimization framework, taking into account aerostructural constraints and exploiting the anisotropic properties of composite materials. The proposed methodology integrates Finite Element (FE) software, an in-house Reduced Order Model (ROM) framework for nonlinear aeroelastic analyses, and Particle Swarm Optimization (PSO). This method, implemented in the Nonlinear Aeroelastic Simulation Software (NAS2) package, facilitated the streamlined design of composite wings with optimized aeroelastic and structural performance. The paper is divided into two main parts. Part 1 introduces a Multidisciplinary Design Optimization (MDO) approach for high-aspect-ratio composite wings, leading to the development of a baseline wing model. Part 2 evaluates the effectiveness of the FWT and TWT devices in alleviating gust loads on the baseline wing, with a focus on the Root Bending Moment (RBM) as a critical criterion for comparison. In wingtip modeling, geometrical nonlinearity is incorporated, and elastic trim is adjusted in each iteration to accommodate shape changes under load and aerodynamic panel movement is synchronized with structural adjustments.

Wiring connector-terminated cables based on manipulation planning with collision-free EMD net

In this paper, we propose a manipulation planning method for cable wiring in the assembly of electric appliances etc. We address a scenario where a robot grasps a connector attached to the end of a cable and has to bring the connector to a socket. To accomplish this automatically, we propose a novel manipulation planning method. The method extends the Encode-Manipulate-Decode network (EMD net), which can predict shape changes of deformable objects and generate robot motion sequences for producing desired shape transitions. This enables us to find connector trajectories that avoid collision between the cable and the surrounding environment. We conducted experiments with several different cable lengths. We also introduce some functions required for real-world wiring, such as online cable shape modification. Experimental results show that the proposed method can achieve stable manipulation of real cables.

Discontinuous, biphasic, ontogenetic shifts in the metabolic allometry of aquatic animals?

Several investigations in recent years have reported patterns of discontinuous, biphasic, loglinear variation in the metabolic allometry of aquatic animals. These putative shifts in pattern of allometry have been attributed to changes in the primary site for gas exchange from cutaneous to branchial as animals undergo ontogenetic changes in size, shape, and surface area. Because of the important implications of the earlier research with regard to both physiology and evolution, I re-examined data that purportedly support claims of discontinuous, biphasic allometry in oxygen consumption versus body size of American eels (Anguilla rostrata) and spiny lobsters (Sagmariasus verreauxi). I used ANCOVA to fit three different statistical models to each set of logarithmic transformations and then assessed the fits by Akaike's Information Criterion. The observations for both species were described better by a single straight line fitted to the full distribution than by a biphasic model. Eels, lobsters, and other aquatic animals undergo changes in shape and surface area as they grow, but such changes are not necessarily accompanied by changes in the pattern of metabolic allometry.

Assessment of Sperm Morphometry in Evaluating Male Infertility

Background: Infertility is a complex issue affecting 15% of couples of reproductive age, with men accounting for 40%-50% of infertility cases. Semen analysis comprises various descriptive measures of sperm and seminal fluid to determine semen quality. Transforming qualitative descriptions of sperm deformities and shape changes into quantitative terms can aid in identifying sub-visual abnormalities. This study aimed to evaluate sperm morphometry parameters in both infertile and fertile men. Methods and Results: The study enrolled a total of 101 participants, divided into three groups: Group A included 38 subfertile patients with varicocele, Group B included 33 patients with idiopathic infertility (23 with asthenozoospermia and 10 with oligozoospermia), and Group C (the control group) included 30 healthy fertile men. The mean age of patients was 31.6±5.81, 31.3±6.0, and 29.47±4.27 years in Groups A, B, and C, respectively. Scrotal duplex examinations were performed to identify the presence of varicocele. Semen samples were collected following WHO Manual (2010). Semen dynamic and morphological analyses were conducted using CASA (Computer-Assisted Semen Analysis, MIRALAB, ISO9001, ISO13485). We found that sperm concentration, total sperm count, sperm progressive motility, and sperm progressive+non-progressive motility were significantly lower in Group A and Group B than in Group C (P=0.000 in all cases); however, there were no differences between Group A and Group B regarding these parameters (Table 5). The sperm morphology index was significantly lower in Group A than in Group C (P=0.0024); no differences were found between Group B and Group C and Group B and Group A. The mean value of the sperm deformity index was significantly lower in Group A than in Group C P=0.004). Conclusion: Our study highlights the significant association between sperm morphology and male infertility in varicocele and idiopathic subfertile males.

Fluid–acoustic interactions around an expanding pipe with orifice plates

Expanding pipes with orifice plates are often utilized as silencers for fluid machinery. However, intense tonal sounds can be generated from a flow through such expanding pipes. To clarify the mechanism of tonal sound from a flow through a circular expanding pipe with two orifice plates and the conditions for intense acoustic radiation, the flow and acoustic fields are directly solved based on the compressible Navier–Stokes equations. Phase-averaged flow fields indicate the occurrence of periodic vortex shedding in the free shear layers of the expanding pipe, resulting in acoustic radiation. The effects of the orifice radius and freestream Mach number on the acoustic radiation are focused on. The computational results demonstrate that vortex rings or spiral vortices are generated in the cavities formed by the orifice plates, where the primary vortical shape changes, depending on the freestream Mach number and orifice radius. The collision of the vortex ring and spiral vortex with the orifice plate or downstream edge of the expanding pipe leads to the occurrence of circumferentially in-phase and one-wavelength-mode pressure fluctuations, respectively. The orifice radius also affects the convective velocity of vortices and the position of the acoustic source, varying the frequency of the acoustic radiation. The findings of this research provide the first clarifications of fluid–acoustic interactions in an expanding pipe with orifice plates.

Crb3 is required to organize the apical domain of multiciliated cells.

Cell shape changes mainly rely on the remodeling of the actin cytoskeleton. Multiciliated cells (MCCs) of the mucociliary epidermis of Xenopus laevis embryos, as they mature, dramatically reshape their apical domain to grow cilia, in coordination with the underlying actin cytoskeleton. Crumbs (Crb) proteins are multifaceted transmembrane apical polarity proteins known to recruit actin linkers and promote apical membrane growth. Here, we identify the homeolog Crb3.L as an important player for the migration of centrioles or basal bodies (collectively centrioles/BBs) and apical domain morphogenesis in MCCs. Crb3.L is present in cytoplasmic vesicles close to the ascending centrioles/BBs, where it partially colocalizes with Rab11a. Crb3.L morpholino-mediated depletion in MCCs caused abnormal migration of centrioles/BBs, a reduction of their apical surface, disorganization of their apical actin meshwork and defective ciliogenesis. Rab11a morpholino-mediated depletion phenocopied Crb3.L loss-of-function in MCCs. Thus, the control of centrioles/BBs migration by Crb3.L might be mediated by Rab11a-dependent apical trafficking. Furthermore, we show that both phospho-activated ERM (pERM; Ezrin-Radixin-Moesin) and Crb3.L are recruited to the growing apical domain of MCCs, where Crb3.L likely anchors pERM, allowing actin-dependent expansion of the apical membrane.

Actin-membrane linkers: Insights from synthetic reconstituted systems

At the cell surface, the actin cytoskeleton and the plasma membrane interact reciprocally in a variety of processes related to the remodeling of the cell surface. The actin cytoskeleton has been known to modulate membrane organization and reshape the membrane. To this end, actin-membrane linking molecules play a major role in regulating actin assembly and spatially direct the interaction between the actin cytoskeleton and the membrane. While studies in cells have provided a wealth of knowledge on the molecular composition and interactions of the actin-membrane interface, the complex molecular interactions make it challenging to elucidate the precise actions of the actin-membrane linkers at the interface. Synthetic reconstituted systems, consisting of model membranes and purified proteins, have been a powerful approach to elucidate how actin-membrane linkers direct actin assembly to drive membrane shape changes. In this review, we will focus only on several actin-membrane linkers that have been studied by using reconstitution systems. We will discuss the design principles of these reconstitution systems and how they have contributed to the understanding of the cellular functions of actin-membrane linkers. Finally, we will provide a perspective on future research directions in understanding the intricate actin-membrane interaction.

Ankrd26 is a retinoic acid-responsive plasma membrane-binding and -shaping protein critical for proper cell differentiation

Morphogens are important triggers for differentiation processes. Yet, downstream effectors that organize cell shape changes in response to morphogenic cues, such as retinoic acid, largely remain elusive. Additionally, derailed plasma membrane-derived signaling often is associated with cancer. We identify Ankrd26 as a critical player in cellular differentiation and as plasma membrane-localized protein able to self-associate and form clusters at the plasma membrane in response to retinoic acid. We show that Ankrd26 uses an N-terminal amphipathic structure for membrane binding and bending. Importantly, in an acute myeloid leukemia-associated Ankrd26 mutant, this critical structure was absent, and Ankrd26's membrane association and shaping abilities were impaired. In line with this, the mutation rendered Ankrd26 inactive in both gain-of-function and loss-of-function/rescue studies addressing retinoic acid/brain-derived neurotrophic factor (BDNF)-induced neuroblastoma differentiation. Our results highlight the importance and molecular details of Ankrd26-mediated organizational platforms for cellular differentiation at the plasma membrane and how impairment of these platforms leads to cancer-associated pathomechanisms involving these Ankrd26 properties.

Flow over a radiating multi-filamentous structure with various opening angles: From disk-like to cone-like shape

Flow over a radiating multi-filamentous structure with various opening angles has been investigated numerically at low and moderate Reynolds numbers. The opening angle, as the major geometric parameter for investigation, varies from 180° to 40° and the overall shape changes from disk-like to cone-like. The overall model drag decreases monotonously as the magnitude of the opening angle decreases. The opening angle effects on the drag-enhancement are then investigated in terms of the velocity distributions, the structures of the recirculation region, and the pressure distributions. As the Reynolds number increases, the wake structure loses its steadiness and the optimal opening angle is found to be approximately 60° when the critical Reynolds number for a steady recirculation structure becomes maximum. The opening angle effects on the wake steadiness in terms of the intensity of the shear layer are investigated as well. On the one hand, the exit velocity—a quantitative indication of the rate of the base bleed—decreases with the decreasing of the opening angle, which promotes wake unsteadiness. This phenomenon can be attributed to the effective gap width between adjacent filaments and the intensity of the virtual barrier from both macro- and micro-perspectives. On the other hand, a small opening angle decreases the thickness of shear layer and thus the unsteadiness is suppressed. These two effects compete and the balance is reached when the opening angle is near 60°.

Using Bright Point Shapes to Constrain Wave Heating of the Solar Corona: Predictions for DKIST

Magnetic bright points on the solar photosphere mark the footpoints of kilogauss magnetic flux tubes extending toward the corona. Convective buffeting of these tubes is believed to excite magnetohydrodynamic waves, which can propagate to the corona and deposit heat there. Measuring wave excitation via bright point motion can thus constrain coronal and heliospheric models, and this has been done extensively with centroid tracking, which can estimate kink-mode wave excitation. DKIST is the first telescope to provide well-resolved observations of bright points, allowing shape and size measurements to probe the excitation of other wave modes that have been difficult, if not impossible, to study to date. In this work, we demonstrate a method of automatic bright point tracking that robustly identifies the shapes of bright points, and we develop a technique for interpreting measured bright point shape changes as the driving of a range of thin-tube wave modes. We demonstrate these techniques on a MURaM simulation of DKIST-like resolution. These initial results suggest that modes other than the long-studied kink mode could increase the total available energy budget for wave heating by 50%. Pending observational verification as well as modeling of the propagation and dissipation of these additional wave modes, this could represent a significant increase in the potency of wave-turbulence heating models.

In vivo confocal microscopy findings after Descemet stripping only with and without topical ripasudil supplementation in Fuchs endothelial dystrophy

PurposeTo report corneal epithelial and corneal endothelial cell (CEC) changes following Descemet stripping only (DSO) with and without topical ripasudil using in vivo confocal microscopy (IVCM). MethodsProspective interventional case series of patients who underwent DSO for Fuchs endothelial dystrophy with or without postoperative topical ripasudil (4%, 6 times per day). Patients underwent IVCM (ConfoScan 3; NIDEK Technologies, Padova, Italy) at baseline, monthly until corneal clearance, and then every 6 months. En face images were obtained of the epithelium, anterior and posterior corneal stroma, and endothelium of the central and superior cornea. The epithelial and endothelial layer images were evaluated qualitatively. ResultsIVCM imaging was obtained from 34 patients, 26 (76%) of whom were supplemented with ripasudil and 8 (24%) of whom were not. Two eyes (6%) did not clear and required a keratoplasty. IVCM confirmed epithelial and endothelial cell morphology changes and reestablishment of a CEC mosaic. Hyperreflective nuclei, pleomorphism, multinucleated cells, and pseudoguttae were identified within the descemetorhexis. In patients on ripasudil, epithelial cells demonstrated transition from stratified squamous to spindle cell shape in regions of ripasudil-induced honeycomb edema. Migrating cells adopted an amoeboid shape and cytoplasm elongation when crossing to central stroma. Transient epithelial cell morphology changes and endothelial cell amoeboid shape changes appear to be uniquely associated with ripasudil. Rarely, figures were noted in both ripasudil-treated and non-ripasudil-treated corneas that resembled mitotic bodies. ConclusionsCECs display a range of adaptive mechanisms during healing to re-form the endothelial mosaic following DSO. Ripasudil administration appears to induce unique epithelial and endothelial cell changes.

A Complex Interplay Between Pluton Emplacement, Tectonic Deformation, and Plate Kinematics in the Cretaceous Sierra Nevada Magmatic Arc, California

AbstractThe relation of plate kinematics to the structural record of arc plutons and their host rocks is complex and still not fully understood. We address this issue through a combination of field mapping, structural analysis, anisotropy of magnetic susceptibility analysis, and fabric modeling in the Late Cretaceous Tuolumne Intrusive Complex, Sierra Nevada, California. A pattern of anti‐clockwise rotation from ∼NNW–SSE to WNW–ESE steep foliations and change in fabric ellipsoid shape from oblate to prolate was revealed in successively emplaced Kuna Crest (∼95–92 Ma), Half Dome (∼92–89 Ma), and Cathedral Peak (∼89–84 Ma) granodiorites. The numerical model indicates that the Kuna Crest was emplaced in a transpressional setting with an angle of convergence α = 60–40°, whereas the Half Dome and Cathedral Peak required simultaneous vertical constriction overprinted by transpression with α = 35–15°. This transition, which occurred at ∼92 Ma, is accompanied by a shallowing of the lineation plunge observed also in other ∼88–84 Ma central Sierra Nevada plutons. Provided that the Cretaceous Sierra Nevada arc was constructed during overall dextral transpression, these transitions reflect significant changes in kinematics, where ∼107–92 Ma plutons were emplaced during pure shear‐dominated transpression, which was followed by a transition to wrench‐dominated transpression recorded in ∼92–84 Ma plutons. Such a transition in kinematics is explained as a result of progressively increasing obliquity of the relative convergence of the Farallon plate subducting beneath the North American continental margin, in agreement with most paleogeographic reconstructions.

Timing of Surgery for Asymptomatic Primary Mitral Regurgitation: Possible Value of Early, Serial Measurements of Left Ventricular Sphericity.

Asymptomatic primary mitral regurgitation due to myxomatous degeneration of the mitral valve leaflets may remain so for long periods, even as left ventricular function progresses to a decompensated stage. During the early compensated stage, the ventricle's initial response to the volume overload is an asymmetric increase in the diastolic short axis dimension, accomplished by a diastolic shift of the interventricular septum into the right ventricular cavity, creating a more spherical left ventricular diastolic shape, increasing diastolic filling and stroke volume. Early valve repair is recommended to reduce postoperative left ventricular dysfunction. Early serial measurements of left ventricular sphericity index [LV-Si]. during the compensated stage of mitral regurgitation might identify subtle changes in left ventricular shape and assist in determining the optimal earliest timing for surgical intervention.