Shape Modification Research Articles

Hybridization and its impact on the ontogenetic allometry of skulls in macaques.

The role of hybridization in morphological diversification is a fundamental topic in evolutionary biology. However, despite the accumulated knowledge on adult hybrid variation, how hybridization affects ontogenetic allometry is less well understood. Here, we investigated the effects of hybridization on postnatal ontogenetic allometry in the skulls of a putative hybrid population of introduced Taiwanese macaques (Macaca cyclopis) and native Japanese macaques (Macaca fuscata). Genomic analyses indicated that the population consisted of individuals with varying degrees of admixture, formed by male migration from Japanese to Taiwanese macaques. For overall skull shape, ontogenetic trajectories were shifted by hybridization in a nearly additive manner, with moderate transgressive variation observed throughout development. In contrast, for the maxillary sinus (hollow space in the face), hybrids grew as fast as Taiwanese macaques, diverging from Japanese macaques, which showed slow growth. Consequently, adult hybrids showed a mosaic pattern, that is, the maxillary sinus is as large as that of Taiwanese macaques, while the overall skull shape is intermediate. Our findings suggest that the transgressive variation can be caused by prenatal shape modification and nonadditive inheritance on regional growth rates, highlighting the complex genetic and ontogenetic bases underlying hybridization-induced morphological diversification.

Identifying non-anthropogenic accumulation in zooarchaeological assemblages using naive Bayesian classifier: A trace-oriented actualistic taphonomic approach in the hyperarid coasts of the Atacama desert

The taphonomic evaluation of zooarchaeological assemblages is paramount for compelling interpretations of past subsistence strategies, palaeoecological interactions and overall biasing of the anthropogenic bone deposition and modification by non-anthropogenic agents. A recent trend in this field, has focused on bone surface modifications (BSM) to successfully generate reference frameworks for critical evaluation of the interpretive potential of selected zooarchaeological samples by examining BSM patterns produced by known agents in experimental settings. These approaches compare anthropogenic and non-human generated patterns using different machine learning (ML) algorithms, classifying and assigning sets of traces to specific processes such as gnawing, scoring or intentional fracture. We propose a simplification in two key aspects to make this new arising area of ML assisted taphonomic interpretation more accessible for zooarchaeologists. First, we encourage a trace oriented multivariate data recording protocol for taphonomic analysis including the most commonly recorded BSM plus others such as shape modification, penetrative modification and element or tissue loss modifications thus expanding comparative potential. Second, we offer a ML approach based on Naïve Bayes Classifier (NBC) that discriminates each given observation by comparing to actualistic taphonomic patterns to determine the average percentage of non-anthropogenic modification within zooarchaeological samples. To illustrate the potential value of these proposals for taphonomical interpretation, we analyzed seven different Mid to Late Holocene assemblages containing avian and mammal remains from the coastal platform in the hyperarid core of the Atacama Desert. We compared their alteration with a local sample of actualistic data recovered to characterize regional taphonomic patterns. A NBC was trained with a 75% random selection of the total archaeological and actualistic samples. Afterwards we tested the remaining sample, achieving over 90% accuracy in determining whether a random specimen from any sample corresponded to an actualistic or an archaeological context implying key differences in taphonomic trace patterns.

Hydrological and climate impacts on river characteristics of pahang river basin, Malaysia

The climate, geomorphological changes, and hydrological elements that have occurred have all influenced future flood episodes by increasing the likelihood and intensity of extreme weather occurrences like extreme precipitation events. River bank erosion is a natural geomorphic process that occurs in all channels. As modifications of sizes and channel shapes are made to transport the discharge, sediment abounds from the stream catchment, and floods are triggered dramatically. The aim of this study is to analyze the flood-sensitive regions along the Pahang River Basin and determine how climate and river changes would have an impact on flooding based on hydrometeorological data and information on river characteristics. The study is divided into three stages, namely the upstream, middle stream, and downstream of the Pahang River. The main primary hydrometeorological data and river characteristics, such as Sinuosity Index, Dominant Slope Range and Entrenchment Ratio collected as important inputs in the statistical analysis process. The statistical analyses, namely HACA, PCA, and Linear Regression applied in river classification. The result showed that the middle stream and downstream areas demonstrated the worst flooding affected by anthropogenic and hydrological factors. Rainfall distribution is one of the factors that contributed to the flood disaster. There are strong correlations between the Sinuosity Index (SI) and water level, which indicates that changes occurred at both planform and stream classification. The best management practices towards sustainability are based on the application of the outcomes that have been obtained after the analysis of Pahang River planform changes, Pahang River geometry, and the local rainfall pattern in the Pahang River Basin.

Woven Endo Bridge shape modification contributes to decrease in adequate occlusion rate after Woven Endo Bridge implantation for wide-neck bifurcation intracranial aneurysms.

Recently, a novel device, the Woven Endo Bridge (WEB), was developed for wide-neck bifurcation intracranial aneurysms (WNBAs). The aim of this study is to investigate factors that contribute to adequate occlusion (AO) after the operation using detailed radiological images. The subjects were 29 patients with 29 aneurysms who received WEB implantation for WNBAs between December 2020 and April 2022. We assessed the contributing factors to AO by retrospectively comparing the AO group and non-AO group. The mean age was 64.6 ± 13.1years, and 18 were female (62.1%). The mean aneurysm dome width, aneurysm height, and aneurysm neck diameter were 4.8 ± 0.6mm, 5.1 ± 0.6mm, and 3.7 ± 0.6mm, respectively. After about 6months, 22 of 29 patients (75.9%) had AO. Complications were observed in 2 patients (6.9%), renal artery injury in one, and minor cerebral infarction in another, but the modified Rankin scale scores of both patients remained unchanged. Multivariate analysis extracted only WEB shape modification (WSM) as a contributing factor to AO (odds ratio: 0.912, p = 0.0287). WEB implantation for WNBAs was a treatment modality with acceptable efficacy and safety. WSM was the only significant factor contributing to non-AO after the treatment. We should clarify the mechanisms or causes of WSM to achieve AO after WEB implantation in future.

Diving into dual functionality: Swim bladder muscles in lionfish for buoyancy and sonic capabilities.

Although the primary function of the swim bladder is buoyancy, it is also involved in hearing, and it can be associated with sonic muscles for voluntary sound production. The use of the swim bladder and associated muscles in sound production could be an exaptation since this is not its first function. We however lack models showing that the same muscles can be used in both movement and sound production. In this study, we investigate the functions of the muscles associated with the swim bladder in different Pteroinae (lionfish) species. Our results indicate that Pterois volitans, P. radiata and Dendrochirus zebra are able to produce long low-frequency hums when disturbed. The deliberate movements of the fin spines during sound production suggest that these sounds may serve as aposematic signals. In P. volitans and P. radiata, hums can be punctuated by intermittent louder pulses called knocks. Analysis of sonic features, morphology, electromyography and histology strongly suggest that these sounds are most likely produced by muscles closely associated with the swim bladder. These muscles originate from the neurocranium and insert on the posterior part of the swim bladder. Additionally, cineradiography supports the hypothesis that these same muscles are involved in altering the swim bladder's length and angle, thereby influencing the pitch of the fish body and participating in manoeuvring and locomotion movements. Fast contraction of the muscle should be related to sound production whereas sustained contractions allows modifications in swim bladder shape and body pitch.

Effects of surface tension and elasticity on critical points of the Kirchhoff–Plateau problem

AbstractWe introduce a modified Kirchhoff–Plateau problem adding an energy term to penalize shape modifications of the cross-sections appended to the elastic midline. In a specific setting, we characterize quantitatively some properties of minimizers. Indeed, choosing three different geometrical shapes for the cross-section, we derive Euler–Lagrange equations for a planar version of the Kirchhoff–Plateau problem. We show that in the physical range of the parameters, there exists a unique critical point satisfying the imposed constraints. Finally, we analyze the effects of the surface tension on the shape of the cross-sections at the equilibrium.

Effects of Current Collector on Internal Visualization of Solid Oxide Cells

Visualization of reactions occurring inside a solid oxide cell (SOC) during operation is difficult due to the limitation of the operatable temperature to use various sensors and measurement equipment. Therefore, we are investigating a visualization method to combine three-dimensional simulation with in-operando temperature observation inside SOCs. In this study, we focused on evaluating the effect of a current collector shape on the cell performance and temperature distribution. As a result, we confirmed that the effects of several current collector shape modifications appeared in the temperature distribution. Based on the calculated temperature and current density distributions, we proposed an appropriate current collector shape for observing the temperature distribution inside the cell by experiment. Using the practical observation setup model considered in this study, the influence of sulfur poisoning on the temperature distribution was also calculated and evaluated.

Recent progress on sonochemical production for the synthesis of efficient photocatalysts and the impact of reactor design

Sonochemical-assisted synthesis has flourished recently for the design of photocatalysts. The main power used is ultrasound that allows the nanomaterials shape and size modification and control. This review highlights the effect in formation mechanism by ultrasound application and the most common photocatalysts that were prepared via sonochemical techniques. Moreover, the challenge for the suitable reactor design for the synthesis of materials or for their photocatalytic evaluation is discussed since the most prominent reactor systems, batch, and continuous flow, has both advantages and drawbacks. This work summarises the significance of sonochemical synthesis for photocatalytic materials as a green technology that needs to be further investigated for the preparation of new materials and the scale up of developed reactor systems to meet industrial needs.

Form and contour: breeding and genetics of organ shape from wild relatives to modern vegetable crops.

Shape is a primary determinant of consumer preference for many horticultural crops and it is also associated with many aspects of marketing, harvest mechanics, and postharvest handling. Perceptions of quality and preference often map to specific shapes of fruits, tubers, leaves, flowers, roots, and other plant organs. As a result, humans have greatly expanded the palette of shapes available for horticultural crops, in many cases creating a series of market classes where particular shapes predominate. Crop wild relatives possess organs shaped by natural selection, while domesticated species possess organs shaped by human desires. Selection for visually-pleasing shapes in vegetable crops resulted from a number of opportunistic factors, including modification of supernumerary cambia, allelic variation at loci that control fundamental processes such as cell division, cell elongation, transposon-mediated variation, and partitioning of photosynthate. Genes that control cell division patterning may be universal shape regulators in horticultural crops, influencing the form of fruits, tubers, and grains in disparate species. Crop wild relatives are often considered less relevant for modern breeding efforts when it comes to characteristics such as shape, however this view may be unnecessarily limiting. Useful allelic variation in wild species may not have been examined or exploited with respect to shape modifications, and newly emergent information on key genes and proteins may provide additional opportunities to regulate the form and contour of vegetable crops.

Virtual Design of 3D-Printed Bone Tissue Engineered Scaffold Shape Using Mechanobiological Modeling: Relationship of Scaffold Pore Architecture to Bone Tissue Formation.

Large bone defects are clinically challenging, with up to 15% of these requiring surgical intervention due to non-union. Bone grafts (autographs or allografts) can be used but they have many limitations, meaning that polymer-based bone tissue engineered scaffolds (tissue engineering) are a more promising solution. Clinical translation of scaffolds is still limited but this could be improved by exploring the whole design space using virtual tools such as mechanobiological modeling. In tissue engineering, a significant research effort has been expended on materials and manufacturing but relatively little has been focused on shape. Most scaffolds use regular pore architecture throughout, leaving custom or irregular pore architecture designs unexplored. The aim of this paper is to introduce a virtual design environment for scaffold development and to illustrate its potential by exploring the relationship of pore architecture to bone tissue formation. A virtual design framework has been created utilizing a mechanical stress finite element (FE) model coupled with a cell behavior agent-based model to investigate the mechanobiological relationships of scaffold shape and bone tissue formation. A case study showed that modifying pore architecture from regular to irregular enabled between 17 and 33% more bone formation within the 4-16-week time periods analyzed. This work shows that shape, specifically pore architecture, is as important as other design parameters such as material and manufacturing for improving the function of bone tissue scaffold implants. It is recommended that future research be conducted to both optimize irregular pore architectures and to explore the potential extension of the concept of shape modification beyond mechanical stress to look at other factors present in the body.

Shaping bridge decks for VIV mitigation: A wind tunnel data-driven adaptive surrogate-based optimization method

Vortex-induced vibration (VIV) of deck girders frequently drives the wind-resistant design of wind-sensitive bridges from the preliminary to final design stages. Shaping bridge decks is a proven strategy to mitigate VIV. While significant shape modifications are commonly restricted to preliminary design stages, only minor medications are possible at advanced design stages, typically involving adding flow modifiers or changing the shape and location of existing appendages. These mitigation strategies have been implemented in the last decades by carrying out expensive wind tunnel campaigns and following heuristic design rules. This paper proposes an experimental data-driven adaptive surrogate-based optimization approach to systematically identify optimum deck shapes that minimizes the economic cost of the bridge while fulfilling the VIV project specifications. The methodology is conceived to carry out simultaneously the general and detailed shape design of the final deck configuration by harnessing a sequential sampling plan aiming at reducing the sectional model construction costs. The proposed holistic design framework is successfully applied to a real application case involving 26 wind tunnel tests of 1.8-meter wide sectional models to figure out the optimal gap distance and location of maintenance tracks of a twin-box deck equipped with all the appendages included in the final deck design.

Example-based dynamic façade design using the facade daylighting performance improvement (FDPI) indicator

It remains challenging to conduct an efficient dynamic façade design. In this article authors try to address this issue introducing the façade daylighting performance improvement (FDPI) indicator aimed to evaluate the performance of a dynamic (adaptive) façade from its daylighting performance point of view. To illustrate the FDPI application the authors introduced the preliminary dynamic façade concept for an office building located in Tel Aviv (Hot-summer Mediterranean Climate Csa) with further shape modification based on the daylighting performance analysis compared to the three alternatives representative of different typologies of dynamic facades. Al Bahr, One Ocean and The University of Southern Denmark façade systems were simulated under the same weather and building conditions of the preliminary dynamic façade concept and were considered as a benchmark for the study. The final dynamic façade concept elaborated by the authors in the preliminary comparative workflow showed noticeable daylight performance improvement with respect to the case studies comparative scenarios. The FDPI metric allowed to estimate a daylighting performance improvement of 43% of the final dynamic façade concept over the case study dynamic façade that showed the best performance in the daylighting simulations.

Correcting for Endogeneity in Models with Bunching

We develop a novel control function approach in models where the treatment variable has bunching at one corner of its support. This situation typically arises when the treatment variable is a constrained choice and some observations choose the corner solution. The method exploits distributional shape restrictions but makes no exclusion restrictions. We provide estimators and establish their asymptotic behavior, prove the convergence of the bootstrap, and develop tests of the identification assumptions. An application reveals that watching television has no effect on cognitive skills and a negative effect on noncognitive skills in children.

Suppression of LPS-activated inflammatory responses and chromosomal histone modifications in macrophages by micropattern-induced nuclear deformation.

Macrophages are important immune effector cells which participate various physiological and pathological conditions. Numerous studies have demonstrated the regulation of macrophage phenotype by micropatterns. It is well accepted that micropatterns affect cellular behaviors through changing cell shape and modulating the associated mechanical sensors on the plasma membrane and cytoskeleton. However, the role of nucleus, which serves as a critical physical sensing device, is often ignored. Herein, we found the nuclear deformation and the subsequently increased chromosomal histone methylation (H3K36me2) may contribute to the micropattern-induced suppression of macrophage inflammatory responses. Specifically, macrophages on micropatterned surfaces expressed lower levels of key inflammatory genes, compared with those on flat surfaces. Further investigation on macrophage nuclei showed that micropatterned surfaces cause shrinkage of nucleus volume and compaction of chromatin. Moreover, micropatterned surfaces elevated the methylation level of H3K36me2 in macrophages, while decreased the methylation level of H3K4me3. Our study provides new mechanistic insight into how micropatterns affect macrophage phenotype and highlights the importance of nuclear shape and chromatin histone modification in mediating micropattern-induced change in cell behaviors.

Tuning LSPR of Thermal Spike-Induced Shape-Engineered Au Nanoparticles Embedded in Si3N4 Thin-Film Matrix for SERS Applications.

While gold nanoparticles (Au NPs) are widely used as surface-enhanced Raman spectroscopy (SERS) substrates, their agglomeration and dynamic movement under laser irradiation result in the major drawback in SERS applications, viz., the repeatability of SERS signals. We tune the optical and structural properties of size- and shape-modified Au NPs embedded in a thin silicon nitride (Si3N4) matrix by intense electronic excitation with swift heavy ion (SHI) irradiation with the aim of overcoming this classical SERS disadvantage. We demonstrate the shape evolution of a single layer of Au NPs inserted between amorphous Si3N4 thin films under fluences of 120 MeV Au9+ ions ranging between 1 × 1011 and 1 × 1013 ions cm-2. This shape modification results in the gradual blue shift of the localized surface plasmon resonance (LSPR) dip until 1 × 1012 ions/cm2 and then a sudden diminishment at 1 × 1013 ions/cm2. Finite domain time difference (FDTD) simulations further justify our experimental optical spectra. The dynamical NP aggregation and dissolution, in addition to NP elongation and deformation at different fluences, are noted from 2D grazing incidence small-angle X-ray scattering (GISAXS) profiles, as well as cross-sectional transmission electron microscopy (X-TEM). The systematic shape evolution of metal NPs embedded in the insulating matrix is shown to be due to thermal spike-induced localized melting and a localized pressure hike upon SHI irradiation. Utilizing this specific control over the characteristics of Au NPs, viz., shape, size, interparticle gap, and corresponding optical response via SHI irradiation, we demonstrate their applications as very stable SERS substrates, where the separation between NPs and analyte does not alter under laser illumination. Thus, these irradiated SERS active substrates with controlled NP size and gap provide the optimal conditions for creating localized electromagnetic hotspots that amplify the SERS signals, which do not alter with time or laser exposure. We found that the film irradiated with 1 × 1011 exhibits the highest SERS intensity due to its optimal NP size distribution and shape. Thus, not only our study provides a SERS substrate for stable and repeatable signals but also the understanding depicted here opens new research avenues in designing SERS substrates, photovoltaics, optoelectronic devices, etc. with ion beam irradiation.

Compression behavior of RC wall-like columns strengthened using NSM/CFRP system without shape modification

The wall-like columns are commonly employed in high-rise buildings for carrying heavy loads without affecting the usable space. However, the retrofitting of these columns often becomes essential under some circumstances. Thus, the designers are looking for strengthening schemes that do not cause changes in the column section for which a combination of near-surface mounted (NSM) bars and carbon fiber reinforced polymer (CFRP) confinement can be adopted. This study was undertaken with the objective of developing such a scheme and studying the confinement provided by CFRP wrapping on wall-like columns. In this study, besides testing two control columns, four columns strengthened using different schemes were tested in axial compression. The performance of the schemes was assessed in terms of the failure modes, load-carrying capacity, and different characteristics of the load-displacement plots. The best scheme was found to be the one wherein the column was strengthened using NSM steel bars connected to the column heads, along with the wrapping of three CFRP sheets covering the NSM rebars. Two analytical models were proposed to estimate the peak load. The first model used the approach of both the ACI 318-19 code and ACI 440.2R-17 guidelines, whereas, the second model utilized the formulas of both Eurocode 2 and the ACI 440.2R-17. The second model predicted the peak load of retrofitted columns more accurately than the first one with prediction errors for the second model varying from 2% to 9%.

Design and Comparison of three Unconventional Shaped DRAs for 60GHz Application

Shape modification and analysis of a conventional circular dielectric resonating antenna for 60 GHz application has been included in this paper. With The conformist shapes have been modified and a comparative study has been done among the unconventional designs based on scattering parameter, antenna gain and directivity. The circular shaped DRA has been modified as Biconvex, Plano convex and biconcave shaped DRA. With the dimension 20 mm × 20 mm × 1.6 mm, FR4 Epoxy material is used for the substrate. Alumina_92pct material with a dielectric constant of 9.2 has been used for the dielectric resonators. Frequency range from 55 GHz to 65 GHz has been considered and the resonant frequencies have been found as 58.7 GHz, 59.7 GHz and 55.5 GHz for Biconvex DRA, Plano Concave DRA and Biconcave DRA respectively. A comparative study has been done among all these three DRAs to find out the best DRA for 60 GHz WLAN application.

Difference in Kernel Shape and Endocarp Anatomy Promote Dehiscence in Pistachio Endocarp

A fully split shell in pistachio (Pistacia vera) is a trait that is preferred by consumers and is a criterion in evaluating the grade of the pistachio nut. However, although the expanding kernel has been hypothesized to provide the physical force needed for shell split, the mechanisms that control shell split remain unknown. Furthermore, it is intriguing how the shell, or endocarp, splits at the suture ridge when there is no clear dehiscence zone. The objectives of this study were 1) to identify traits associated with dehiscence in fruit in the high-split rate cultivar Golden Hills when compared with the lower split rate cultivar Kerman and determine the anatomic features associated with endocarp dehiscence at the suture region, and 2) to examine the effect of kernel shape on endocarp dehiscence. We determined that, despite the fact that the pistachio endocarp is composed primarily of a single type of polylobate sclerenchyma cell, specialization of cell shape and size at the suture site results in smaller, more flattened cells. We report there is a furrowing of the shell at the dorsal and apical suture sites, where dehiscence initiates. This furrowing is not observed at the ventral suture site or in the indehiscent fruit of Pistacia atlantica, a species that has been used as rootstock for P. vera. In addition, the size of the kernel in the sagittal axis (the width) is strongly associated with a greater split rate. Based on our results, a tentative model emerges in which, in the absence of specialized cell types, cell shape modification can create an anatomically distinct region that is mechanically weak in the endocarp for the initiation of dehiscence, whereas the force from the width of the kernel is necessary for the shell split rate difference as observed in cultivars.

An updated overview of some factors that influence the biological effects of nanoparticles.

Nanoparticles (NPs) can be extremely effective in the early diagnosis and treatment of cancer due to their properties. The nanotechnology industry is developing rapidly. The number of multifunctional NPs has increased in the market and hundreds of NPs are in various stages of preclinical and clinical development. Thus, the mechanism underlying the effects of NPs on biological systems has received much attention. After NPs enter the body, they interact with plasma proteins, tumour cell receptors, and small biological molecules. This interaction is closely related to the size, shape, chemical composition and surface modification properties of NPs. In this review, the effects of the size, shape, chemical composition and surface modification of NPs on the biological effects of NPs were summarised, including the mechanism through which NPs enter cells, the resulting oxidative stress response, and the interaction with proteins. This review of the biological effects of NPs can not only provide theoretical support for the preparation of safer and more efficient NPs but also lay the foundation for their clinical application.

A U-Net with Statistical Shape Restrictions Applied to the Segmentation of the Left Ventricle in Echocardiographic Images

This paper aims to introduce an innovative approach to semantic segmentation by leveraging a convolutional neural network (CNN) for predicting the shape and pose parameters of the left ventricle (LV). Our approach involves a modified U-Net architecture with a regression layer as the final stage, as opposed to the traditional classification layer. This modification allows us to predict all the shape and pose parameters of a statistical shape model, including rotation, translation, scale, and deformation. The adapted U-Net is trained using data from a point distribution model (PDM) of the LV. The experimental results demonstrate a mean Dice coefficient of 0.82 on good quality images, and 0.66 including mean and low-quality images. Our approach successfully overcomes a common issue encountered in CNN-based semantic segmentation. Unlike the inaccurate pixel classification that often leads to unwanted blobs, our CNN generates statistically valid shapes. These shapes hold significant potential in initializing other methods, such as active shape models (ASMs). Our novel CNN-based approach provides a novel solution for semantic segmentation, offering shapes and pose parameters that can enhance the accuracy and reliability of subsequent medical image analysis methods.