Specific Shape Research Articles

A detection method based on nonlinear spiking neural systems for infrared small targets

Due to the lack of specific shapes and textures and susceptibility to background clutter and noise interference, infrared small target detection has always been a challenging task. The nonlinear spiking neural P (NSNP) system is a type of neural computing model inspired by the nonlinear spiking mechanisms of biological neurons. It can better identify the internal relationships between small objects, and based on this. This paper presents a variant of NSNP systems, called nonlinear spiking neural P systems with two states or NSNP-TS systems. Based on this variant, a new method for infrared small target detection is proposed. The core idea is the employment of the nonlinear spiking mechanism of the NSNP-TS system. Moreover, a preprocessing component is introduced to find potential targets from the original infrared image, with the aim of making the firing mechanism of the NSNP-TS system more effective. The experimental results on real sequences from 8 different environmental backgrounds indicate that the proposed method outperforms other comparative methods.

Mechanical properties of basalt fiber/ epoxy resin composites

This paper presents a study regarding the obtaining, characterizing and mechanically testing a new laminar composite material, consisting of epoxy resin reinforced with basalt plain fabric. The composites were obtained by manual lay-up, cross-link stage being developed by pressure molding in a hydraulic press. Rectangular plates were obtained and cut into samples with specific shapes, for the mechanical tests (tensile, three-point bending and compression). After testing, the fracture zone was analyzed using optical microscopy to observe the behavior of the composite following the mechanical stresses applied (fracture mechanism, voids presence and fiber delamination identification). Due to the low costs and non-hazardous nature, basalt fibers can be a serious competitor in the production of laminar composites that could successfully replace ordinary glass fiber composites. The mechanical properties in tensile, three-point bending, and compression of epoxy-resin-impregnated basalt fiber composites are comparable and even exceed those of widely used epoxy-resin-impregnated fiberglass composites.

A nonconservative kinetic model under the action of an external force field for modeling the medical treatment of autoimmune response

In this paper, we develop a nonconservative kinetic framework to be applied to the study of immune system dysregulation. From the modeling viewpoint, the model regards a system composed of stochastically interacting agents, under the action of an eternal force field. According to the application perspectives of this paper, the external force field has a specific analytical shape. In this case, some analytical results are proved, i.e. existence, uniqueness, positivity, and boundedness of solution of the related Cauchy problem, at least locally in time. Then, the model is refined to be implemented for the study of treatment strategies in case of autoimmune response. Specifically, we distinguish the autonomous case from the nonautonomous one, representing the absence or delivery of drugs, respectively. The former allows us to gain some stability results. Whereas, the latter is qualitatively studied. Numerical simulations are provided for both schemes.

Electrochemical deposition and characterization of cuprous oxide crystallites on stainless substrates: Growth mechanism and morphological analysis

In this article, we present the growth process of cuprous oxide (Cu2O) crystallites on the stainless substrates from an aqueous cupric acetic solution under electrochemical deposition method. Copper acetate (Cu(Ac)2) aqueous solution was used as the electrolyte with the applied potential and reaction time for electrodeposition were varied in this study. Pure Cu2O crystallites of cubic phase with specific surface morphologies were observed under electrodeposited at certain temperature. The specific shape of crystallites electrodeposited at 25 °C is the structure with four identical pyramid-shaped leaves pointing outward and a pointing upward stamen in the middle. The crystal growth type can be classified as the branching growth through a surface diffusion mechanism based on the growth exponent (L ∝ t1/2). The growth of Cu2O crystal is suggested to be surface diffusion of adatoms in dendrite branching growth. A mechanism for the growth of Cu2O crystals under electrodeposition was proposed based on the XPS results. As the temperature increases, the morphology of Cu2O crystals under electrodeposition becomes thinner, but the shape does not change a lot.

Design criteria for conformal integration of flexible electronics on advanced aircraft surfaces

This paper introduces a set of design criteria that aim to integrate flexible electronics onto three-dimensional surfaces in a mechanically adaptive manner. Previous studies have been limited to conformal integration on specific shapes (Such as spherical surfaces and corrugated surfaces) of rigid surfaces or soft substrates, there is a lack of a universal design strategy that takes into account the complexity of substrate shapes and varying hardness. To address this gap, the paper outlines a mechanical model that utilizes Hertzian contact theory to describe the interaction between the thin film and the substrate, and the conformal surface morphology and stress state were derived from minimizing the total energy of the island-substrate structure. The proposed formulations are verified through finite element methods and experiments, analyzing the effects of Young's modulus, in-plane size, and thickness of the “island” on its conformability. Therefore, this paper proposes a generic on-demand conformal design strategy that takes into account the complexity and hardness of the substrate. This study's findings will contribute to the development of conformal electronics that can be used in various fields, such as epidermal electronics, flexible robots, robot electronic skin, and aircraft smart skin.

First description of the baubellum in the spectacled bear Tremarctos ornatus (Mammalia: Ursidae).

The baubellum (os clitoridis) is a bone found in the clitoris of many female eutherian mammals and is homologous to the baculum in males. In contrast to the baculum, the baubellum has received very little attention regarding its morphological or interspecific diversity, or on hypotheses for its function. The presence of the baubellum in bears (Ursidae) has only been established and mentioned in the literature for the Ursus genus, and not for the other genera of bears. Moreover, no scaled photographs are available for baubella of this clade, and the sizes reported vary between sources. We hereby present and describe the baubellum of a spectacled bear (Tremarctos ornatus), providing a detailed account of baubella in a basal ursid species. The baubellum of Tremarctos is slightly bowed dorsally, with two small prominences at the distal apex. The length of the Tremarctos baubellum in this study is comparable to that of Ursus americanus (American black bear). We infer the specific shape, with longitudinal ridges, of the baubellum in Tremarctos could indicate a discrete function during copulation or sexual arousal. However, future studies, especially regarding the associated soft tissues, will be required to confirm whether this is indeed the case. Our study expands the understanding of baubella within Ursidae, providing new data (including a three-dimensional model) that can be used to further explore the morphological diversity and function of this enigmatic extra-skeletal bone.

Nanometer-scale electron beam shaping with thickness controlled and stacked nanostructured graphite

The generation of small electron probes is the basis for various techniques in which such a probe is scanned across a sample, and special probe shapes like vortices can be desirable, e.g., to gain insight into magnetic properties. Micron-scale phase plates or holographic masks, in combination with demagnifying optics, are usually used for creating such special probe wave functions. Here, we present the fabrication of nanometer-sized phase plates based on thickness-selected and stacked graphite layers as well as an analysis of their performance. First, a spiral phase plate is demonstrated that creates a vortex beam with an orbital angular momentum of 1 and an outer radius of 2.5 nm. Second, a three-level Fresnel lens built from two nanopatterned graphite membranes is presented, which achieves a focal spot with a full width at half maximum of 5.5 nm. Third, an array of electron sieves is demonstrated, each of which creates a focal spot with a radius of 2 nm, and the array is applied as a Shack–Hartmann wavefront detector. These elements allow the generation of few-nanometer sized focused probes or vortices without the need for additional optical elements.

Specific pelvic shape in patients with developmental dysplasia of the hip on 3D morphometric homologous model analysis.

To clarify the morphological factors of the pelvis in patients with developmental dysplasia of the hip (DDH), three-dimensional (3D) pelvic morphology was analyzed using a template-fitting technique. Three-dimensional pelvic data of 50 patients with DDH (DDH group) and 3D pelvic data of 50 patients without obvious pelvic deformity (Normal group) were used. All patients were female. A template model was created by averaging the normal pelvises into a symmetrical and isotropic mesh. Next, 100 homologous models were generated by fitting the pelvic data of each group of patients to the template model. Principal component analysis was performed on the coordinates of each vertex (15,235 vertices) of the pelvic homologous model. In addition, a receiver-operating characteristic (ROC) curve was calculated from the sensitivity of DDH positivity for each principal component, and principal components for which the area under the curve was significantly large were extracted (p<0.05). Finally, which components of the pelvic morphology frequently seen in DDH patients are related to these extracted principal components was evaluated. The first, third, and sixth principal components showed significantly larger areas under the ROC curves. The morphology indicated by the first principal component was associated with a decrease in coxal inclination in both the coronal and horizontal planes. The third principal component was related to the sacral inclination in the sagittal plane. The sixth principal component was associated with narrowing of the superior part of the pelvis. The most important factor in the difference between normal and DDH pelvises was the change in the coxal angle in both the coronal and horizontal planes. That is, in the anterior and superior views, the normal pelvis is a triangle, whereas in DDH, it was more like a quadrilateral.

Mechanical and magnetic properties of Fe33Co28Ni28Ta5Al6 high entropy alloy fabricated by selective laser melting

Abstract Selective laser melting (SLM) can obtain metal magnetic materials with specific shapes and good mechanical properties, which has potential application value in the field of engineering. In this study, the soft-magnetic high-entropy alloy (HEA) Fe33Co28Ni28Ta5Al6 was prepared via SLM. The microstructure, mechanical, and magnetic properties of the sample are investigated. The sample consists of a single face-centered-cubic (FCC) phase. The tensile yield strength, ultimate tensile strength, and elongation of the sample are 752 MPa, 1067 MPa, and 27% respectively. Furthermore, the sample has a low coercivity of 970 A m−1, moderate saturation magnetization of 1.17 T, and high electrical resistivity of 121 μΩ cm. This work would provide a pathway for the rapid manufacturing high-performance soft-magnetic HEA.

Occurrent beliefs about emotions predict emotion regulation in everyday life.

Whether and how people regulate their negative emotions matters a great deal. However, it is not yet clear why people regulate as they do. One promising idea is that people's beliefs shape their emotion regulation choices, and initial evidence indicates that individuals' dispositional beliefs about emotions are indeed associated with general patterns of emotion regulation. The present study extends prior work on emotion beliefs to better understand how occurrent (i.e., momentary) beliefs about helpfulness, controllability, and justification of specific emotions shape whether and how people regulate negative emotions in everyday life. Participants (N = 143; U.S. community college students recruited in 2022; 76% female; age = 18-60) completed a 7-day experience-sampling protocol in which they were pinged three times per day to describe their most recent negative experiences and answer questions about their emotions, occurrent beliefs about emotions, and emotion regulation. With respect to whether people regulate their emotions, results reveal that people regulate their emotions more when they perceive them to be less helpful. Exploratory analyses additionally show that people regulate negative emotions more when they perceive them to be more controllable and when emotional intensity is relatively high. In terms of how people regulate their emotions, people are more likely to use reappraisal when emotions are seen as more helpful, more controllable, and less justified; and more likely to use distraction when emotions are seen as less helpful and more justified. These findings contribute to a more fine-grained understanding of how beliefs shape emotion regulation in everyday life.respect to whether people regulate their emotions, results reveal that people regulate their emotions more when they perceive them to be less helpful. Exploratory analyses additionally show that people regulate negative emotions more when they perceive them to be more controllable and when emotional intensity is relatively high. In terms of how people regulate their emotions, people are more likely to use reappraisal when emotions are seen as more helpful, more controllable, and less justified; and more likely to use distraction when emotions are seen as less helpful and more justified. These findings contribute to a more fine-grained understanding of how beliefs shape emotion regulation (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Morphological adaptation of the tongue of okapi (Okapia johnstoni Artiodactyla, Giraffidae)-Anatomy, histology, and ultrastructure.

The aim of this study was to describe the morphology of the tongue of the okapi, and to compare the results with other ruminants including browsers, intermediates and grazers. The material was collected post-mortem from two animals from a Zoological Garden. The structure of the okapi tongue, focusing of the shape of the tongue, lingual surface, its papillae and lingual glands, was examined using gross morphology, light and polarized microscopy, and by scanning electron microscopy. The okapi tongue was characterized by dark pigmentation on the lingual dorsum (except lingual torus) and on the whole ventral surface. Two types of filiform papillae were observed, with additional, even 6-8 projections at their base. The round fungiform papillae were present at a higher density, up to 16/cm2, on the ventro-lateral area of the lingual apex. Round and elongate vallate papillae were arranged in two parallel lines between the body and root of the tongue. Numerous taste buds were detected within the epithelium of their vallum, while fungiform papillae had sparse taste buds. A lack of foliate papillae was noted. Very small conical papillae, some lenticular in shape, were present on the lingual torus. Thick collagen type I fibers were dominant over collagen type III fibers in the connective tissue of the lingual papillae. The mucous acini units were dominant among lingual glands, indicating that the secretion of okapi lingual glands was mostly mucous. In many aspects, the tongue of okapi resembles the tongue of other ruminants. The specific lingual shape and lingual surface, together with the lingual glands, support the processing of plant food, such as young and soft leaves. Although okapi tongue is characterized by smaller conical papillae compared to other ruminants, its high number of vallate papillae is similar that found in other browsers, intermediate and grazers. Thus the number of gustatory papillae rather indicates that this feature is not related to the type of feeding.

The specific shapes of capillaries are associated with worse prognosis in patients with invasive breast cancer.

Angiogenesis is considered essential for tumor progression; however, whether histological counting of blood vessel numbers, expressed as microvessel density (MVD), can be a prognostic factor in breast cancer remains controversial. It has been suggested that the specific morphology of blood vessels such as glomeruloid microvascular proliferation (GMP) is associated with clinical parameters. Here, we aimed to clarify the significance of MVD with revised immunohistochemistry and to identify new blood vessel shapes that predict prognosis in breast cancer. Four hundred and eleven primary breast cancer specimens were collected, and the sections were immunohistochemically stained with CD31 (single staining) and CD31 and Collagen IV (double staining). The prognosis of patients was examined based on the MVD value, and the presence of GMP and other blood vessels with other specific shapes. As a result, high MVD value and the presence of GMP were not associated with worse prognosis. By contrast, patients with deep-curved capillaries surrounding tumor cell nests (C-shaped) or excessively branched capillaries near tumor cell nests showed a significantly poor prognosis. The presence of these capillaries was also correlated with clinicopathological parameters such as Ki-67 index. Thus, the morphology of capillaries rather than MVD can be a better indicator of tumor aggressiveness.

OVERVIEW OF CONTROVERSIAL ISSUES IN CHARACTER AND VALUES EDUCATION PROVIDED THROUGH DISTANCE EDUCATION

The primary objective of education is to enhance individuals' thinking skills and their thought processes including the cultivation of character and the internalization of values. Engaging students in discussions on controversial topics encourage critical thinking. This research aims to investigate how students enrolled in the Non-Thesis Master's Degree Program on Character and Values Education through Distance Learning perceive controversial issues such as discrimination, violence, and gender. Furthermore, the study aims to examine the influence of the Global Education in Character and Values Education course on students' perceptions of these controversial issues. The course incorporates various activities, assignments, and discussions to connect these topics with character and values education. The study also seeks to provide insights into students' perspectives on controversial issues in character and values education and explore how a specific course shape their perception and understanding of these matters.

Maximum spanning capacity of a catenary arch under self-weight against buckling

ABSTRACT This paper is concerned with a novel problem of determining the maximum spanning capacity of an elastic catenary arch under its own weight against in-plane buckling. The arch supports may be fixed or pinned or rotationally restrained. The arch is assumed to have a uniform cross-section throughout its entire length and the arch length is assumed to be inextensible. Additionally, catenary arches with a crown hinge are considered. The specific shape of a family of catenary curves is specified by the height-to-span ratio (or the horizontal force) which is to be determined for maximum buckling capacity of the arch. The Hencky bar-chain model is adopted for the elastic buckling analysis as it avoids the need to formulate the governing equation for buckling and it is also a simple model to understand and for coding. From the maximum in-plane buckling load of the optimal arch solution, the maximum spanning capacity of the arch can then be derived. Presented herein are the maximum spanning capacities, optimal arc length to span ratios and maximum buckling loads of catenary arches with various support and crown conditions.

Dynamics of h-shape narrow bandwidth dissipative soliton in Yb-doped fiber laser

We demonstrate a narrow bandwidth mode-locked ytterbium-doped fiber laser based on the carboxyl-functionalized graphene oxide (GO-COOH). In the combination of GO-COOH and intracavity filtering effects, the narrow bandwidth spectrum exhibits an h-shape at 1060.76 nm central wavelength with a 3-dB bandwidth of 0.47 nm. Furthermore, the 3-dB bandwidth can be compressed to 0.049 nm by adjusting the polarization controller. The formation of h-shape dissipative soliton has been investigated by applying the dispersive Fourier transformation and numerical simulation. The h-shape narrow bandwidth dissipative soliton we demonstrated provides a new insight for investigating the evolution dynamics of solitons with special shapes.

A method for determining the spectral relaxation functions of polymers under single stretching of micro samples

The principles of designing products made of the latest complex-structured polymer composite materials necessitate the need to take into account the large-scale structural effects determined by processes at the supramolecular and molecular levels of the polymer: relaxation, kinetic (breaking and recombination of chemical bonds), recrystallization of supramolecular structures, etc. The development of these processes is described by relaxation functions, which, in turn, can be calculated using the functions of relaxation time spectra. The purpose of the work was to develop a specialized equipment for testing micro-samples with a variable working part for uniaxial stretching along with the experimental technique and computational algorithms for processing the obtained measurement data, and experimental approbation of the developed approach to determining spectral relaxation functions. A method is proposed for estimating relaxation functions not at fixed stress levels within linear elasticity, at secant points of deformation diagrams, at fixed values of the linear elasticity modulus, but within an extended range of the sample deformation up to pre-rupture states. A set of test equipment designed for tensile tests of micro-samples with a thickness of the working part of 0.2 – 1.2 mm has been developed. The tooling can be installed on modern high-precision breaking machines. Tensile tests of polyethylene terephthalate micro-samples with a thickness of 50 and 175 μm were carried out taking into account the scale factor. A tensile test of micro-samples that are technologically stabilized by paper frames of a special shape is described. Diagrams illustrating the kinetics of changes in the spectral relaxation functions of oriented polyethylene terephthalate (PET) are constructed proceeding from the data of testing micro-samples with a constant strain rate. A method for using these diagrams in calculations of empirical relaxation time spectra is described. The results of testing micro-samples of polyethylene terephthalate are presented. Illustrative deformation diagrams of the studied polymer samples and calculated diagrams of functions of relaxation time spectra calculated according to the described method are given.

Crystal structure and shape selection in the growth of 3D metallic crystallites on layered materials: Fe on MoS2

Nucleation and growth of supported 3D metal clusters or crystallites during deposition on MoS2, or on other weakly-adhering layered materials, can potentially produce diverse growth shapes, and even crystal structures differing from the bulk metal. For Fe deposition on MoS2, SEM and AFM observations reveal three distinct crystallite shapes. By comparison with atomistic structure models incorporating realistic Fe-MoS2 interface structures, we conclude that these are: triangular fcc(111) pyramids with sloped {100} side facets; bcc(110) A-frame tents with sloped {100} side facets; and bcc(110) mesas with vertical {100} and {110} side facets. The following picture is proposed for the competitive formation of clusters and crystallites with different structures: (i) small nanoclusters formed at the onset of deposition exhibit facile fluxional dynamics allowing sampling of different crystal structures and shapes; (ii) sufficient fluxionality implies a Boltzmann distribution of sampled structures, and thus coexistence of different structures follows from the demonstrated similar energies for those structures; (iii) growing clusters reach a threshold size above which the characteristic time scale for restructuring exceeds that for cluster growth. Thereafter, clusters are locked-in to a specific crystal structure and shape as revealed by imaging of larger crystallites. Despite a penalty for fcc(111) over bcc(111) pyramids based on bulk energetics, favorable surface and interface energies makes them preferable for smaller sizes.

MEIAT-CMAQ: A modular emission inventory allocation tool for Community Multiscale Air Quality Model

The Modular Emission Inventory Allocation Tool for Community Multiscale Air Quality Model (MEIAT-CMAQ) refines emission inventories by providing detailed spatial (horizontal and vertical), temporal, and species allocations, enhancing the accuracy of CMAQ performance. Its efficient algorithm and modular design offer flexibility for managing both gridded and tabulated inventories, widely used in various sectors. In addition, the shapefiles with specific shapes supported by MEIAT-CMAQ can address the allocation challenges in transportation emissions. The evaluation of MEIAT-CMAQ, using model-ready inventories before (BASE scenario), and after allocation without (EXPR scenario) or with (EXPR-V scenario) vertical allocation, demonstrates significant improvements in the mean bias (MB) of gaseous pollutants (O₃, NO₂, CO). In both the EXPR and EXPR-V scenarios, the MB for O3 exhibits notable enhancements, with respective improvements of 5.7% and 26.9%. For NO₂, corresponding MB improvements are even more pronounced, reaching 27.6% and 61.7% in the EXPR and EXPR-V scenarios, respectively. Likewise, enhancements are observed in the MBs of CO, demonstrating increases of 8.4% and 45.2% in the EXPR and EXPR-V scenarios, respectively. Moreover, with regard to spatial accuracy, the incorporation of the MEIAT-CMAQ model yields significant improvements. Specifically, in the EXPR scenarios, spatial accuracy for O3 and NO2 demonstrates respective enhancements of 13.5% and 9.5%. Furthermore, the inclusion of vertical allocation leads to additional enhancements in CO, NO₂, and PM2.5, resulting in improvements of 17.6%, 16.6%, and 23.2%, respectively. MEIAT-CMAQ provides an efficient method for transforming coarse-resolution emission inventories into high-resolution files directly useable in the model, offering enhanced flexibility for users to select any period for generating model-ready emission files. This capability provides substantial technical support for automating processes within business departments and significantly improves the performance of high-resolution modeling and forecasting.

Gel microspheres enhance the stemness of ADSCs by regulating cell-ECM interaction

The gel microsphere culture system (GMCS) showed various advantages for mesenchymal stem cell (MSC) expansion and delivery, such as high specific surface area, small and regular shape, extensive adjustability, and biomimetic properties. Although various technologies and materials have been developed to promote the development of gel microspheres, the differences in the biological status of MSCs between the GMCS and the traditional Petri dish culture system (PDCS) are still unknown, hindering gel microspheres from becoming a culture system as widely used as petri dishes. In the previous study, an excellent “all-in-one” GMCS has been established for the expansion of human adipose-derived MSCs (hADSCs), which showed convenient cell culture operation. Here, we performed transcriptome and proteome sequencing on hADSCs cultured on the “all-in-one” GMCS and the PDCS. We found that hADSCs cultured in the GMCS kept in an undifferentiation status with a high stemness index, whose transcriptome profile is closer to the adipose progenitor cells (APCs) in vivo than those cultured in the PDCS. Further, the high stemness status of hADSCs in the GMCS was maintained through regulating cell-ECM interaction. For application, bilayer scaffolds were constructed by osteo- and chondro-differentiation of hADSCs cultured in the GMCS and the PDCS. The effect of osteochondral regeneration of the bilayer scaffolds in the GMCS group was better than that in the PDCS group. This study revealed the high stemness and excellent functionality of MSCs cultured in the GMCS, which promoted the application of gel microspheres in cell culture and tissue regeneration.

Utilizing Artificial Neural Networks for Geometric Bone Model Reconstruction in Mandibular Prognathism Patients

Patient-specific 3D models of the human mandible are finding increasing utility in medical fields such as oral and maxillofacial surgery, orthodontics, dentistry, and forensic sciences. The efficient creation of personalized 3D bone models poses a key challenge in these applications. Existing solutions often rely on 3D statistical models of human bone, offering advantages in rapid bone geometry adaptation and flexibility by capturing a range of anatomical variations, but also a disadvantage in terms of reduced precision in representing specific shapes. Considering this, the proposed parametric model allows for precise manipulation using morphometric parameters acquired from medical images. This paper highlights the significance of employing the parametric model in the creation of a personalized bone model, exemplified through a case study targeting mandibular prognathism reconstruction. A personalized model is described as 3D point cloud determined through the utilization of series of parametric functions, determined by the application of geometrical morphometrics, morphology properties, and artificial neural networks in the input dataset of human mandible samples. With 95.05% of the personalized model’s surface area displaying deviations within −1.00–1.00 mm relative to the input polygonal model, and a maximum deviation of 2.52 mm, this research accentuates the benefits of the parametric approach, particularly in the preoperative planning of mandibular deformity surgeries.