Column Morphology Research Articles

Roll‐to‐Roll (R2R) Processing of Large‐Area Flexible Piezoresistive Films with Magnetically Z‐Aligned Nickel Microcolumnar Morphology

AbstractFlexible pressure sensors are highly sought after for applications like rehabilitation healthcare, advanced wearable electronics, automotive safety, etc. This work demonstrates a scalable method for fabricating functional piezoresistive films using external magnetic fields to engineer the columnar microstructures. The continuous roll‐to‐roll processing involves directed self‐assembly of ferromagnetic Nickel particles within a flexible elastomer to achieve quasi 1–3 composites with low particle concentrations. In this process, polymer precursor‐microparticle system is subjected to a spatiotemporal evolution of temperature and magnetic fields simultaneously. Offline techniques like in‐plane alignment, through‐thickness light transmission, and viscosity evolution determine the influence of transient process conditions on final column morphology. Real‐time visualization in the X‐Y plane quantified by image analysis allowed tracking of morphological evolution where columns are formed separated by particle depletion zones leading to optical transparency. This characteristic is used to determine the kinetics of column formation via out‐of‐plane light transmission during Z‐alignment. Isothermal and non‐isothermal rheokinetics identified the gel point required to “freeze” the column structures. The scalability of the process is demonstrated by producing a 5.18 m long and 15.24 cm wide piezoresistive film with columns in thickness direction. The piezoresistive performance of produced anisotropic films is demonstrated under continuous uniaxial loading‐unloading cycles.

Dactyliform appendage contributes to delayed selfing in the diminutive orchid Stigmatodactylus sikokianus

Societal Impact StatementUnderstanding plant reproductive strategies is vital for conserving endangered species. This study reveals a novel self‐pollination mechanism in the diminutive orchid Stigmatodactylus sikokianus, facilitated by the movement of a finger‐like appendage beneath the stigma. While this less‐than‐1‐mm‐long structure inspired the name Stigmatodactylus, its ecological function remained unknown for over 130 years—until now. The findings suggest that this appendage facilitates delayed self‐pollination, likely ensuring reproductive success under conditions of pollinator scarcity. Furthermore, the research highlights the value of integrating taxonomy with functional morphology to advance our understanding of pollination ecology.Summary Orchidaceae is one of the largest and most morphologically diverse plant families, largely due to intricate relationships with pollinators. However, autonomous self‐pollination is relatively common, likely as an adaptation to limited pollinator availability. This study examines the reproductive mechanism of the diminutive orchid Stigmatodactylus sikokianus, focusing on the finger‐like appendage beneath the stigma. The reproductive biology of S. sikokianus was investigated through pollination observations, artificial pollination experiments, and detailed studies of column morphology. Pollination experiments demonstrated that S. sikokianus primarily relies on autonomous self‐pollination, as indicated by high fruit set in bagged flowers and no fruit set in emasculated ones. Microscopic analysis revealed that the dactyliform appendage arcs toward the stigma, maintaining its straight structure, and eventually adheres to the stigma surface, allowing contact between the appendage apex and pollinia. UV microscopy showed thick bundles of pollen tubes penetrating the appendage adhered to the stigma and reaching the base of the column. The absence of pollen tube formation before contact between the appendage apex and pollinia suggests that autogamy occurs exclusively through the appendage at a later flowering stage. This study uncovers a novel self‐pollination mechanism in orchids, where the movement of the stigma appendage likely facilitates delayed selfing. This mechanism ensures seed production and likely reproductive success in S. sikokianus, enabling it to thrive in shaded environments with limited pollinator availability. The discovery highlights the value of integrating taxonomic and ecological approaches, as morphological traits provide valuable insights into species life histories.

Simulation of the performance of pillar array columns using the pore-throat ratio as efficiency descriptor.

Traditional packed beds in chromatography suffer from increased band broadening due to the random nature of packing, leading non-ideal fluid flow and channeling. To address these challenges, pillar array columns have been developed, offering improved performance over random packing thanks to their homogenous fluid profiles. The study aims to i) evaluate fluid dynamics and chromatographic performance across different PAC morphologies, ii) establish the influence of column morphology on performance, and iii) assess the correlation between chromatographic performance and hydrodynamic parameters. Approximately 200 PAC morphologies with different pillar shapes, pillar sizes, rotations and radial stretching were simulated using the finite element method (FEM). The pore-throat ratio was introduced as a predictor for separation efficiency, showing a strong positive correlation between this ratio and the minimum reduced plate height hmin. It is suggested that a more homogenous fluid profile, indicated by a pore-throat ratio approaching 1, is associated with higher column efficiency and permeability, allowing for larger optimal velocities and reduced separation time. For PACs, the hmin is close to 0.25 as the pore throat ratio approaches 1. The simplicity of calculating the pore-throat ratio from the column structure without the need for chromatographic experiments or modeling makes it a practical tool for predicting column performance.

Fabrication and application of aminated metal–organic cages doped monolithic column for pipette tip micro solid-phase extraction of eight phenolic compounds in milk

A Zr-based metal–organic tetrahedron (ZrT-1-NH2) doped monolithic column was sythesized and applied for pipette tip micro solid-phase extraction (PT-μSPE) of 8 phenolic compounds. Scanning electron microscopy, energy dispersive spectrometry, Fourier transform infrared spectroscopy, thermogravimetric analysis and N2 adsorption and desorption experiment were employed to characterize the morphology, composition, structure and thermal stability of the monolithic column. The experimental results showed that the monolithic column had good stability and excellent adsorption selectivity for phenolic compounds. The adsorption mechanism was speculated to be π-π stacking and H-bond interaction based on ESP maps. After the extraction conditions were optimized, a PT-μSPE-high performance liquid chromatography-ultraviolet detector (HPLC-UV) method was established for the detection of 8 phenolic compounds in milk. The PT-μSPE-HPLC-UV method has wide linearities (0.3–1000 μg L−1) (R2 > 0.997), low limits of detection (0.1–0.3 μg L−1), satisfactory recoveries (80.5–113.6 %) and high precision (RSDs < 6.7 %). Thus, the ZrT-1-NH2 doped monolithic column is an ideal medium for the separation and determinaton of phenolic compounds in milk.

Barkeria wixarika (Laeliinae, Epidendroideae, Orchidaceae), a new species from Nayarit, Mexico

Barkeria wixarika is described from Nayarit, Mexico. This new species is morphologically similar to B. uniflora but distinct in its flowering phenology, inflorescence type, petal shape, column morphology, and geographic distribution. Detailed comparisons with related species, including digital plates along with a map highlighting the distribution of the novel species in relation to others are presented. Finally, an updated identification key for Barkeria is provided.

Collaborative form-finding of multiple treelike column structures based on improved numerical inverse hanging method

The mechanical properties of treelike column structures are greatly influenced by their forms, emphasizing the importance of form optimization. However, previous studies have primarily focused on optimizing the morphology of individual treelike column, neglecting the interaction of multiple column structures. This oversight leads to deviation in the optimal morphology. In order to investigate the impact of the deviation on the performances of structures, the collaborative form-finding analysis of multiple column structures has been carried out using improved Numerical Inverse Hanging Method (NIHM). This research is based on the design of a large-span roof structure supported by 8 treelike column structures at the terminal of Dalian Jinzhou Bay Airport. Firstly, the traditional NIHM was improved to achieve collaborative form-finding of multiple treelike column structures. Then the differences between collaborative form-finding analysis of multi columns and individual analysis of single column were discussed in depth. Comparative results show collaborative form-finding exhibits more reasonable over individual form-finding. In the case where all joints are located on one side of the fixed end, the results of individual form-finding are similar to those of the initial model, while collaborative form-finding shows a significant enhancement in mechanical performance. Notably, when there exists a substantial height discrepancy among branch joint, collaborative form-finding achieves a displacement reduction of 21 % compared to individual form-finding, along with a reduction of 35 % in maximum equivalent stress.

Polytetrafluoroethylene (PTFE) microplastics affect angiogenesis and central nervous system (CNS) development of duck embryo

Prolonged exposure to teratogens is known to cause neural tube defects (NTDs), a severe malformation of the central nervous system (CNS) that significantly contributes to global infant mortality. In recent years, exposure to nanoplastics (NPs) has been linked to faulty neural crest closure and altered neurulation by altering cellular adhesion molecules and accumulation of plastic particles in the neural tube leading to NTDs. However, research on the influence of various types of microplastics (MPs) on malformations of the CNS are still limited. In this study, we investigated whether MPs of polytetrafluoroethylene (PTFE)—a type of plastic commonly used as non-stick coatings of cooking utensils can affect angiogenesis and CNS development using ducks as model organisms. PTFE MPs were administered on Day 3 of duck embryo development at varying concentrations (0.01 mg/ml, 0.1 mg/ml, 1 mg/ml, and 5 mg/ml), and angiogenesis was evaluated using a chorioallantoic membrane (CAM) assay. Gross morphology and histology of the spinal column and brain were analyzed on Days 8 and 18, respectively. FTIR confirmed PTFE's structure, while SEM and DLS analyses showed particle sizes between 300 nm and 5 μm, classifying them as MPs. High concentrations (5 mg/ml) of PTFE MPs treated on duck embryos resulted in a 35 % mortality rate and reduced vascular density, suggesting anti-angiogenic effects. Brain and spinal abnormalities, such as encephalomalacia and spinal cord discontinuities were observed in the PTFE-treated embryos. Based on these results, PTFE is an anti-angiogenic and teratogenic agent affecting the development of duck embryos.

L-Cysteine-Bonded Polymeric Monolithic Stationary Phase for Enantioseparation of Dansyl Amino Acids in Capillary Liquid Chromatography.

A chiral monolith stationary phase was fabricated by modifying the monolith surface using L-cysteine through a thiol-epoxy click reaction. L-cysteine-bonded polymer monolith was characterized by scanning electron microscopy/energy-dispersive X-ray and attenuated total reflectance Fourier-transformed infrared. The monomer content and modification temperature were carefully optimized to create a polymer monolith with excellent mechanical stability and permeability. Our findings revealed that the column morphology depended significantly on the porogen concentration and modification temperature for its morphology and efficiency. Adequate pores and binding sites were formed with the optimal porogen content, while a higher modification temperature improved the modification yield, enhancing peak shapes and increasing separation efficiency. The column demonstrated its capability for enantioseparation of dansyl glutamic acid, dansyl aspartic acid, dansyl methionine, and dansyl phenylalanine using a 60mM ammonium acetate buffer solution and acetonitrile in a 20:80 v/v ratio. It maintained good mechanical stability and repeatability with no relative standard deviation exceeding 7%. These results indicated that the L-cysteine-bonded polymer monolith has excellent potential as a chiral stationary phase.

Mining experimental magnetized liner inertial fusion data: Trends in stagnation morphology

In magnetized liner inertial fusion (MagLIF), a cylindrical liner filled with fusion fuel is imploded with the goal of producing a one-dimensional plasma column at thermonuclear conditions. However, structures attributed to three-dimensional effects are observed in self-emission x-ray images. Despite this, the impact of many experimental inputs on the column morphology has not been characterized. We demonstrate the use of a linear regression analysis to explore correlations between morphology and a wide variety of experimental inputs across 57 MagLIF experiments. Results indicate the possibility of several unexplored effects. For example, we demonstrate that increasing the initial magnetic field correlates with improved stability. Although intuitively expected, this has never been quantitatively assessed in integrated MagLIF experiments. We also demonstrate that azimuthal drive asymmetries resulting from the geometry of the “current return can” appear to measurably impact the morphology. In conjunction with several counterintuitive null results, we expect the observed correlations will encourage further experimental, theoretical, and simulation-based studies. Finally, we note that the method used in this work is general and may be applied to explore not only correlations between input conditions and morphology but also with other experimentally measured quantities.

Axial compressive behavior of short columns of BFRP strip-PVC tube composite reinforced fiber recycled concrete

In this paper, axial compression tests were performed on recycled fiber concrete short columns reinforced by BFRP strips and PVC tube. The main variables investigated were the type of reinforcement (BFRP strip reinforcement or BFRP strip-PVC tube composite reinforcement) and the volumetric configuration rate of BFRP (One or three different number of strips layers and 25 mm/37.5 mm/50 mm with different strip spacing). A set of specimens was selected for each experimental group and simulated through ABAQUS to be used to assess the accuracy of the test. The investigation results show that BFRP strip-PVC tube composite reinforcement not only improves the ultimate bearing capacity of the specimen, but also improves the damage morphology of the fiber-recycled concrete short columns. The reinforcement method's effect on the specimen's stiffness is more significant during the nonlinear strengthening phase of the stress-strain curve. The specimen’s peak stress and ultimate strain of the specimens increased significantly with higher volumetric configuration rate of BFRP. Based on the analysis of the experimental results, the stress-strain calculation model with a softened section is also of better applicability. The study’ results provide a theoretical basis and reference for the future application of fiber recycled concrete.

Sustainable water sterilization by nano-ZnO using anisotropic polysaccharide columns derived from agro-waste stalk

The escalating demand for clean water and proliferation of microbial contamination in water have challenged ecosystems and human health safety. ZnO NPs are widely used as environmental restoration agents, but their efficacy in water decontamination is hindered by low biological toxicity. In order to enhance its sterilization efficiency, we propose a top-down strategy utilizing the unique maze structure of corn stalk pith (CSP) as a germ trapper for ZnO. The in-situ delignified CSP offers abundant active sites for the adsorption of Zn2+, exhibiting the typical behaviors of monolayer, physisorption, endothermicity, spontaneity, and randomness. This adsorption behavior exerts an influence on microscopic morphology of the composite column, consequently resulting in alterations to antibacterial properties. The results show that the hybrid column fabricated under the Zn2+ initial dosage of 1.00 mol/L at 30 h for 40 °C, possesses such optimal features as stacked grain-shaped ZnO NPs of 669.3 mg/g loading amount with adhesion coefficients of 0.73 ∼ 0.86 for bacterial microparticles. Consequently, the assembled bio-filter can eliminate E. coli and S. aureus as high as 99.7 % and 96.5 % respectively, attributed to CSPP labyrinth structure to enhance pathogen capture from water and facilitate ZnO-mediated inactivation. The collective findings emphasize the viability of agro-waste stalks as bio-filters for water purification.

Flexible bistable polymer stabilised cholesteric texture light shutter display

ABSTRACT Bistable cholesteric liquid crystal displays meet various needs such as energy saving, long image storage time, and no backlight; however, their dense polymer network affects the electro-optical performance. In this work, polymer-stabilised cholesteric texture (PSCT) films with polymer spacer columns were prepared by two-step polymerisation using photomask. The effects of crosslinker content and mask polymerisation time on the morphology of the polymer spacer columns and the optoelectronic properties of the PSCT films were investigated. The results suggested that the film showed bistable performance and the formation of polymer spacer columns helped to optimize the contrast ratio of the sample without sacrificing response time. The cyclic experiment indicated that the optimized bistable PSCT film showed good stability. The adhesion strength of the PSCT film to the substrate was essentially the same as that of commercial PDLC. The simple operability and reusability of the process method make it a practical solution for the preparation of bistable PSCT films.

Chromatographic separation by RPLC-ESI-MS of all hydroxyproline isomers for the characterization of collagens from different sources

During collagen biosynthesis, proline is post-translationally converted to hydroxyproline by specific enzymes. This amino acid, unique to collagen, plays a crucial role in stabilizing the collagen triple helix structure and could serve as an important biomarker for collagen content and quality analysis. Hydroxyproline has four isomers, depending on whether proline is hydroxylated at position 4 or 3 and on whether the cis- or trans- conformation is formed. Moreover, as extensive hydrolysis of collagen is required for its amino acid analysis, epimerization may also occur, although to a lesser extent, giving a total of eight possible isomers.The aim of the present study was to develop a reversed-phase high-performance liquid chromatography-UV-mass spectrometry (RPLC-UV-MS) method for the separation and quantification of all eight hydroxyproline isomers. After the chiral derivatization of the hydroxyproline isomers with Nα-(2,4-dinitro-5-fluorophenyl)-L-valinamide (L-FDVA), to enable their UV detection, the derivatized diastereoisomers were separated by testing different C18 column technologies and morphologies and optimizing operative conditions such as the mobile phase composition (solvent, additives), elution mode, flow rate and temperature. Baseline resolution of all eight isomers was achieved on a HALO® ES-C18 reversed-phase column (150×1.5 mm, 2.7 μm, 160 Å) using isocratic elution and MS-compatible mobile phase.The optimized method was validated for the quantification of hydroxyproline isomers and then applied to different collagen hydrolysates to gain insight and a deeper understanding of hydroxyproline abundances in different species (human, chicken) and sources (native, recombinant).

Collapse dynamics and deposition morphology of low-viscocohesive granular columns on a rough horizontal surface.

Using the three-dimensional discrete element method, we numerically investigate the collapse dynamics and deposition morphology of low-viscocohesive granular columns on a rough-horizontal plane by systematically varying a broad range of values of the initial column aspect ratio, cohesive stress, and liquid viscosity. The results show that the kinetic energy, half runout time, and runout distance increase with increasing the initial column aspect ratio but decrease with increasing the cohesive and viscous effects of the binding liquid, while the toe angle and deposit height decrease with increasing the aspect ratio and increase with increasing cohesive stress and liquid viscosity. Remarkably, by defining a dimensionless scaling number that incorporates the Bond number and initial column aspect ratio, this allows us to nicely describe the kinetic energy, half runout time, deposition height, runout distance, and toe angle. These unified descriptions may provide insights into the physical properties of the collapse dynamics and deposition morphology of low-viscocohesive granular columns, leading to good explanations of the complex properties of natural disaster events.

Experimental study and finite element analysis on axial compression performance of CFRP-PVC confined coral seawater and sea-sand concrete columns

In this paper, a composite column using carbon fibre reinforced plastics and polyvinyl chloride composite tube (CFRP-PVC) to constrain coral aggregate seawater sea-sand concrete (CSSC) was proposed, and CFRP was pasted on the inner and outer walls of the PVC tube. To investigate the effects of the number of CFRP layers and void defects on the axial compression performance of PVC tubes, six specimens were made for axial compression loading tests and finite element parameter analysis. The results indicate that due to PVC improving the integrity of CFRP, PVC tube provide a stress transfer path for CFRP, placing CSSC in a triaxial compression state. When both the inner and outer walls of the tube are pasted with CFRP, brittle failure of CFRP-PVC tube can be effectively avoided and have relatively superior mechanical properties. In the same situation, when one layer of CFRP is pasted on the inner wall of the tube, it has better ductility and bearing capacity. When two layers of CFRP are pasted on the outer wall of the tube, the coefficient of constraint stress increase is as high as 121.5%, and the void defect only has a significant impact on ductility. A finite element model of CFRP-PVC confined CSSC columns considering Hashin damage criterion was established based on ABAQUS, accurately predicting the failure process and CFRP damage morphology of test columns under axial load. Parameter analysis shows that when the confinement coefficient of CFRP-PVC confined CSSC columns is less than 0.3 and the height-diameter ratio is greater than 15, the load-displacement curve will lose the strengthening stage, and increasing the number of outer CFRP layers will slightly increase the stiffness of the strengthening stage. A bearing capacity calculation method suitable for CFRP-PVC confined CSSC was proposed based on the model of steel tube confined concrete, with an error of 1.2%.

Lateral impact behaviour of CCFT columns with spherical-cap gap imperfection: Numerical modelling and design method

To clarify the influence of gap imperfection on the impact behaviour of the concrete-filled steel tube (CFT) column, this paper performs numerical modelling on the mechanical responses of the circular CFT columns holding spherical-cap gaps (CCFT-SG) under lateral impact load. The effects of gap ratio, axial compression ratio, impact position, diameter/thickness ratio, boundary condition and material strength on the energy dissipation (Ea), the maximum (Fm) and equivalent impact forces (Feq), the peak (δm) and residual lateral deflections (δr) are analyzed after establishing and validating the finite element (FE) model. The typical failure pattern, time-history curve and contact response between the tube and concrete of the laterally impacted CCFT-SG column are revealed as well. The result declares that the overall failure morphology of the CCFT-SG column imposed with lateral impact showing as overall bending, is similar to that of the common CFT column, but distinct local depression is obtained because of the existence of spherical-cap gaps. With the gap ratio increasing, the Feq, Fm and Ea decrease gradually, while the δm and δr rise slowly. The calculation formulae for predicting the dynamic impact force and resistance of the CCFT-SG column are presented and validated against the existing test and numerical results.

Regionalization of the vertebral column and its correlation with heart position in snakes: Implications for evolutionary pathways and morphological diversification.

Spinal regionalization has important implications for the evolution of vertebrate body plans. We determined the variation in the number and morphology of vertebrae across the vertebral column (i.e., vertebral formula) for 63 snake species representing 13 families using intracolumnar variation in vertebral shape. Vertebral counts were used to determine the position of the heart, pylorus, and left kidney for each species. Across all species we observed a conspicuous midthoracic transition in vertebral shape, indicating four developmental domains of the precloacal vertebral column (cervical, anterior thoracic, posterior thoracic, and lumbar). Using phylogenetic analyses, the boundary between the anterior and posterior thoracic vertebrae was correlated with heart position. No associations were found between shifts in morphology of the vertebral column and either the pylorus or left kidney. We observed that among taxa, the number of preapex and postapex vertebrae could change independently from one another and from changes in the total number of precloacal vertebrae. Ancestral state reconstruction of the preapex and postapex vertebrae illustrated several evolutionary pathways by which diversity in the vertebral column and heart position have been attained. In addition, no conspicuous pattern was observed among the heart, pylorus, or kidney indicating that their relative positions to each other evolve independently. We conclude that snakes exhibit four morphologically distinct regions of the vertebral column. We discuss the implications of the forebody and hindbody vertebral formula on the morphological diversification of snakes.

Effects of cross-section morphology, vascular bundle content and anisotropy on compression failure of laminated bamboo columns

To investigate the mechanical performance of short laminated bamboo column (LBC) with different cross-section morphology and vascular bundle content, three groups of specimens were axially compressed to investigate their elastic modulus, Poisson’s ratio, load capacity and failure mode. The cross-section morphology of bamboo column has little influence on the ultimate bearing capacity of bamboo column, but it has a certain effect on the ductility. The vascular bundle content of LBC has great influence on the mechanical properties, as the mean peak load of group C is 25.16% higher than that of group B1. It is also found that the strength of the LBC depends on the global fiber buckling while the delamination of the fibers results in the complete failure of the LBC.

Cephalometric Evaluation of Cervical Vertebral Column Morphology and Cervical Vertebral Maturation in Subjects with Vertical and Horizontal Growth Pattern

Cephalometric Evaluation of Cervical Vertebral Column Morphology and Cervical Vertebral Maturation in Subjects with Vertical and Horizontal Growth Pattern

The combined effect of cohesion and finite size on the collapse of wet granular columns.

The collapse of low-saturation liquid-containing granular materials is prevalent in nature and industrial processes, and understanding the associated transient dynamics is extremely important for exploring such complex flow processes. In this paper, the collapse of a finite-size wet granular column is systematically studied and the determinants affecting its dynamics are analyzed based on the discrete element model for wet particles and the corresponding small-scale experiments. With the aid of parametric analysis, the dimensionless cohesion parameter containing the system size and grain-scale bond number is proposed, and its relevance in characterizing column stability and collapse dynamics of wet granular materials is further confirmed. For the collapse of wet granular columns with a fixed aspect ratio, the initial height contained in the cohesion parameter is verified to be a manifestation of the finite size effect, which is present in a wet granular collapse and is coupled with the cohesive effect. Such a coupling effect is taken into account in our proposed scaling laws that can be applied to uniformly describe the deposit morphology of wet granular columns after collapse.