Mushroom Structure Research Articles

A Sub-6 GHz/Millimeter-Wave Dual-Wideband Shared-Aperture Antenna by Reusing the Mushroom Structure

A Sub-6 GHz/Millimeter-Wave Dual-Wideband Shared-Aperture Antenna by Reusing the Mushroom Structure

High-Linearity Capacitive 3-D Force-Flexible Tactile Sensor Inspired by Mushroom Structure for Human Motion Monitoring and Robotic Gripping

High-Linearity Capacitive 3-D Force-Flexible Tactile Sensor Inspired by Mushroom Structure for Human Motion Monitoring and Robotic Gripping

Accumulation of Bisphenol A® by Pleurotus spp.-Flow Injection Analysis.

A specific feature of mushrooms (including those of the genus Pleurotus) is their natural ability to absorb and accumulate many chemical substances present in their immediate environment, which makes them an excellent natural sorption material. Hence, fruiting bodies of mushrooms have been recognized for years as excellent indicators of the environment, reflecting its current state. Nevertheless, mushrooms can accumulate both health-promoting substances, such as bioelements, and toxic substances, such as heavy metals and organic compounds, including bisphenol A® (BPA). This organic chemical compound in the phenol group, although it has been withdrawn in the EU since 2010, is widely present in the environment around us. In the present experiment, we aimed to determine the effect of adding BPA to liquid media for in vitro cultures of Pleurotus spp. The biomass increases were determined. Moreover, the degrees of adsorption and desorption of BPA from the obtained freeze-dried biomass in two different environments (neutral and acidic) were determined as a function of time. This is the first study to determine the bioavailability of adsorbed BPA in obtained biomass by extracting the mycelium into artificial digestive juices in a model digestive system. BPA was added to the liquid Oddoux medium in the following amounts: 0.01, 0.5, and 0.5 g/250 mL of medium. The amounts of adsorbed and desorbed BPA were determined by flow injection analysis (FIA) with amperometric detection. The addition of BPA to the substrate reduced the biomass growth in each of the discussed cases. BPA adsorption by the mycelium occurred at over 90% and depended on the morphology of the mushroom (structure, surface development, and pore size). BPA desorption depended on the pH of the environment and the desorption time. Mushrooms are an excellent natural remedial material, but BPA is extracted into artificial digestive juices; therefore, consuming mushrooms from industrialized areas may have health consequences for our bodies.

Eliminating the Scattering of Thin Film Structures.

Rendering invisibility in the wide application scenarios has seen a surge in interest in recent years. Though various approaches have been proposed to realize concealments under different conditions, achieving polarization-independent invisibility for large objects remains a big challenge. Here, we propose to attain invisibility of a large dielectric slab with polarization constraints being totally lifted. This is accomplished by employing an antiscattering coating made of anisotropic metamaterials. We show that by tailoring the electric resonance of a triangular mushroom structure, antiphase electric dipole moment can be induced, resulting in an antipolarization response of the whole metamaterial coatings. By putting the proposed coatings on both sides of a large dielectric slab, a neutralization effect of the total polarization is observed, leading to the peculiar phenomenon of full-polarization invisibility. Our results are validated through full-wave simulations and experimental measurements. Remarkably, the intrinsic null-polarization property of the coating-slab-coating structure guarantees the invisibility feature of a large-scale bulk made by simply stacking the sandwiched composites, which facilitates the application of invisibility in practical scenarios such as the invisibility cloaks and the reflectionless antenna radomes.

Mush-Room Structures–Loaded Coplanar Waveguide Spoof Surface Plasmon Polariton with Reduced Longitudinal Length

Mush-Room Structures–Loaded Coplanar Waveguide Spoof Surface Plasmon Polariton with Reduced Longitudinal Length

A Novel Design of Single-Layer Wideband Differential-Fed Dual-Polarized Patch Antenna Loaded With Mushroom Structures

A Novel Design of Single-Layer Wideband Differential-Fed Dual-Polarized Patch Antenna Loaded With Mushroom Structures

Lagrangian investigation of the interface dynamics in single-mode Rayleigh–Taylor instability

We apply Lagrangian particle tracking to the two-dimensional single-mode Rayleigh–Taylor (RT) instability to study the dynamical evolution of fluid interface. At the onset of the nonlinear RT stage, we select three ensembles of tracer particles located at the bubble tip, at the spike tip, and inside the spiral of the mushroom structure, which cover most of the interfacial region as the instability develops. Conditional statistics performed on the three sets of particles and over different RT evolution stages, such as the trajectory curvature, velocity, and acceleration, reveals the temporal and spatial flow patterns characterizing the single-mode RT growth. The probability density functions of tracer particle velocity and trajectory curvature exhibit scalings compatible with local flow topology, such as the swirling motion of the spiral particles. Large-scale anisotropy of RT interfacial flows, measured by the ratio of horizontal to vertical kinetic energy, also varies for different particle ensembles arising from the differing evolution patterns of the particle acceleration. In addition, we provide direct evidence to connect the RT bubble re-acceleration to its interaction with the transported fluid from the spike side, due to the shear driven Kelvin–Helmholtz instability. Furthermore, we reveal that the secondary RT instability inside the spiral, which destabilizes the spiraling motion and induces complex flow structures, is generated by the centrifugal acceleration.

Wideband multibeam mushroom antenna array with low‐temperature cofired ceramic‐integrated pillbox transition for millimetre‐wave applications

AbstractThis article presents a millimetre‐wave (MMW) wideband multibeam antenna array with a pillbox transition using multilayer low‐temperature cofired ceramic (LTCC) technology. The mushroom structure with dual resonant modes offers wideband performance for radiating array, while an integrated pillbox reflector achieves multibeam scheme. To reduce the design complexity of electrically large pillbox system, two popular pillbox transitions are investigated with a unit model method. The proposed unit model can be used to predict the transmission performance of pillbox reflector in any incident angle. Moreover, the mushroom antenna array and power divider fed by quasi‐TEM wave are also designed using unit model, greatly simplifying the design of electrically large pillbox antenna array. In the final design, the long‐slot pillbox transition, rather than multi‐slot transition, is selected due to its ultrawideband performance and simple structure. The proposed LTCC prototype is analysed and fabricated, obtaining a good agreement between simulation and measurement. The measured results show a −10 dB impedance bandwidth of 17.6% from 31 to 37 GHz, and five beams with ±45° scanning range is achieved with sidelobe level lower than −10 dB.

Rational construction of mushroom-like Ni@N-doped carbon tubes composites with enhanced electromagnetic wave absorption

It is confirmed that electromagnetic wave absorption (EMA) materials with a metal-carbon dual-phase structure has exposed great potential for achieving tunable, strong, and wide EMA. Herein, the mushroom-like Ni@N-doped carbon tubes (NNCTs) are prepared by nickel-catalyzed growth of carbon tubes, realizing carbon encapsulated metal particles. One end of the carbon tube grows and connects to form a bundle of mushroom-like structures, and the other end of the carbon tube is filled with nickel as the mushroom head. The structure control of NNCTs can be achieved by adjusting the amount of catalyst Ni. Appropriate amount of nickel can control the formation of mushroom-like structure. The results show that the structure has a great influence on the EMA performance. Particularly, NNCT-0.5 provides a minimum reflection loss of -60.47 dB with a thickness of 4.0 mm, and the widest effective absorption bandwidth for RL< -10 dB of NNCT-1.5 at a thickness of 2.00 mm was 7.53 GHz (10.47–18.00 GHz). The immobilization of carbon in melamine was achieved by catalytic generation of carbon tubes with metal ions Ni. Metal-carbon biphasic composites introduce dielectric and magnetic losses. The presence of multiple interfaces and voids in the mushroom structure allows tuning the dielectric parameters and optimizing the impedance matching. This work provides an effective strategy for the fabrication of dielectric and magnetic composites with special structures, which has great potential in attenuating electromagnetic wave energy.

Pharmacognostic, Chemical Characterization Studies on Oyster Mushroom (Pleurotus ostreatus)

Pharmacognosy Research,2023,15,3,514-523.DOI:10.5530/pres.15.3.054Published:June 2023Type:Original Article Authors:Prasad Vijay Kadam, Damini Kallyanrao Giram, Sameer Khamroddin Shaikh, Kavita Nilesh Yadav, Abhijit Sampatrao Karanje, and Manohar Janardhan Patil Author(s) affiliations:Prasad Vijay Kadam*, Damini Kallyanrao Giram, Sameer Khamroddin Shaikh, Kavita Nilesh Yadav, Abhijit Sampatrao Karanje, Manohar Janardhan Patil Department of Pharmacognosy, Marathwada Mitra Mandal’s College of Pharmacy, Thergaon, Pune, Maharashtra, INDIA. Abstract:Aim: The purpose of this study is to determine the Pharmacognostic, phytochemical and physicochemical standardization of Pleurotus ostreatus. Materials and Methods: The disease-free oyster mushroom fruiting body was collected during the rainy season from Himgiree Hi-Tech Agro (Mushroom Division) Kalyani Nagar Pune. Their identity and authentication were done. Macromorphology, cytomorphology, powder microscopy, micrometry, physicochemical evaluation, and phytochemical screening were done according to the WHO guidelines and standard methods. Results: Macromorphology of mushroom structure has a broad, oyster or fan-shaped cap, spanning 2-35 cm. yellowish grey colour, chocolaty odor, and significant taste. Cytomorphology of mushroom shows different cells such as aciculate, sphaerodunculate, lanceolate thick-walled, utriform, cornuate, Subcapitate, mucronate, cornuate, clavate 4-sterigmate basidium and in powder microscopy nodulose, isodiametric, snout like pore, spiny, bullet shaped, cuboid. The preliminary phytochemical analysis of the mushroom shows the occurrence of active compounds such as flavonoid, tannin, glycoside, coumarin, phenols, steroid, terpenoids protein and amino acid. Conclusion: The results obtained in this study the Standardization of phytochemical, physico-chemical is a fundamental dimension for sample identification, quality, and purity of oyster mushroom (Pleurotus ostreatus). Keywords:Cytomorphology, Oyster mushroom, Pharmacognostic study, Standardization.View:PDF (866.79 KB)

Design and Analysis of Fractal-Shaped High-Impedance Surface Unit Cell Characteristics

Fractal geometries consistently provide solutions to several electromagnetic design problems. In this paper, fractal geometries such as Hilbert and Moore curves are used to design efficient High-Impedance Surfaces. Modern communication devices have many sensors that are needed to communicate wirelessly. The critical component of wireless communications is antennas. Planar microstrip patch antennas are popular due to their low profile, compactness, and good radiation characteristics. The structural disadvantages of microstrip antennas are that they have surface waves that propagate over the ground plane. High-Impedance Surface (HIS) planes are a prominent solution to minimize and eliminate surface waves. The HIS structures behave as active LC filters that suppress surface waves at their resonance frequency. The resonance frequency of the structure is obtained by its LC equivalent or by analyzing the reflection phase characteristics. This work presents conventional HIS structures similar to mushroom HIS and fractal HIS such as Hilbert curve and Moore curve HIS. The HIS reflection phase characteristics are obtained by applying periodic boundary conditions with plane wave illumination. The results were obtained in terms of the reflection phase angle. The conventional mushroom structures show narrow band characteristics at given dimensions of 10 mm × 10 mm and 20 mm × 20 mm. These structures are helpful in the replacement of PEC ground planes for patch antennas under sub-6 GHz. The Hilbert and Moore fractals are also designed and have a multiband response that can be useful for L, S, and C band applications. Another design challenge of HIS is protrusions, which make design difficult. The work also presents the effect of having vias and the absence of vias on reflection phase characteristics. The response shows the least and no significant effect of vias under the x-band operation.

A Novel Wideband Common-Mode Noise Suppression Filter That Combines Mushroom and Defected Corrugated Reference Plane Structures

A novel wideband common-mode (CM) suppression filter is proposed for high-speed transmission. The filter is embedded in 3 10 mm × 10 mm layers of a printed circuit board (PCB) that combines a mushroom structure and a defected corrugated reference plane structure (MDCRP). Using the novel MDCRP structure generates more resonance frequencies in the CM current return path. This generates a wider CM noise suppression performance. We used a simulation method to obtain the best geometric parameters for the MDCRP structure. The experimental results proved that the full-wave simulation results were consistent with the actual measurement results. This novel filter shows good signal integrity according to actual measurements, and the insertion loss can be kept to less than −2.306 dB from DC to 21 GHz in differential mode (DM). The CM noise can be suppressed by over −10 dB from 5.09 GHz to 20.62 GHz. The fractional bandwidth is 120.8%, and the CM noise improves by 64.5%. An eye diagram proves that the filter can support a 20 Gb/s transmission rate with complete differential signal transmission capability. The MDCRP structure filter can support HDMI 2.0, PCI Express 4.0, USB 3.2, and SATA Express. Therefore, the filter meets current computer and server system products’ design needs.

A numerical study on high-temperature effects of exploding shock waves

A planar shock of initial strength MS = 3.0 was focused to a tiny region in space using a spherically converging test section. The shock accelerates inside the test section, collides with the focusing end wall, and gets reflected. Numerical studies show that the flow behind reflected shock behaves like an expanding jet moving through a confined area. It was observed that this expansion caused the formation of a mushroom-shaped structure. Thermodynamic characterization of the mushroom structure was made, and it was found that the gas temperature inside the mushroom structure is higher than that across the reflected shock itself. High-temperature effects, such as temperature-dependent Cp variations and dissociation–recombination reactions of the test gas, were added to the simulations to better understand the effect of temperature on the expanding hot gas. A reduction of 39% in the peak temperature value was obtained at the focusing end wall. Also, the flow inside the mushroom structure was observed to be a reactive mixture of a hot gas slug. It is observed that prominent molecular dissociation and recombination take place inside the mushroom structure, which is absent across the reflected shock.

A Low-Profile Wideband Patch Antenna With Modified Parasitic Mushroom Structures on Nonperiodic AMC

In this letter, a low-profile wideband antenna working around 28 GHz based on the nonperiodic artificial magnetic conductor (AMC) is presented. Mushroom structures are loaded with central patch to broaden bandwidth. Four vias at edges are added to suppress cross polarization. A parasitically coupled structure is integrated with AMC. The nonperiodic AMC, central patch, and parasitic structures create five resonant modes together. Characteristic mode analysis and effective relative permittivity of AMC are calculated to explain the bandwidth broadening mechanism. A prototype is fabricated to verify the design concept. The measured result shows wide impedance bandwidth of 33% (24.05–33.52 GHz) and high peak gain of 10.24 dBi.

Set/Reset Bilaterally Controllable Resistance Switching Ga‐doped Ge2Sb2Te5 Long‐Term Electronic Synapses for Neuromorphic Computing

AbstractLong‐term plasticity of bio‐synapses modulates the stable synaptic transmission that is quite related to the encoding of information and its emulation using electronic hardware is one of important targets for neuromorphic computing. Ge2Sb2Te5 (GST) based phase change random access memory (PCRAM) has become a strong candidate for complementary‐metal‐oxide‐semiconductor (CMOS) compatible integrated long‐term electronic synapses to cope with the high‐efficient and low power consumption data processing tasks for neuromorphic computing. However, the performance of PCRAM electronic synapses is still quite limited due to the challenges in linear and continuous conductance regulation, which originates from the fast and uncontrollable resistance switching characteristic of conventional PCRAM for the data storage application. Here an in‐depth study is reported on the impact of gallium (Ga) doping on GST (GaGST) structural properties and on the corresponding 0.13 µm CMOS technology fabricated PCRAM integrated devices with a mushroom structure. The Ga doping effectively retarded the crystallization process of GST by augmenting the local disorder of GeTe4‐nGen tetrahedron, which subsequently leads to the Set/Reset bilaterally controllable resistance switching of corresponding PCRAM devices. The optimized 6.5%GaGST electronic synapses demonstrate gradual resistance switching characteristics and a good multilevel retention feature and eventually exhibit outstanding long‐term synaptic plasticity like potentiation/depression and spiking time dependent plasticity in four forms. Such long‐term electronic synapses are applied to handwritten digits recognition (96.22%) and CIFAR‐10 image categorization (93.6%) and attain very high accuracy for both tasks. These results provide an effective method to achieve high performance PCRAM electronic synapses and highlight the great potential of GaGST PCRAM as a component for future high‐performance neuromorphic computing.

Electroplating-based engineering of plasmonic nanorod metamaterials for biosensing applications

Sensing lower molecular weight in a diluted solution using a label-free biosensor is challenging and requires a miniaturized plasmonic structure, e.g. a vertical Au nanorod (AuNR) array-based metamaterials. The sensitivity of a sensor mainly depends on transducer properties and hence for instance, the AuNR array geometry requires optimization. Physical vapour deposition methods (e.g. sputtering and e-beam evaporation) require a vacuum environment to deposit Au, which is costly, time-consuming, and thickness-limited. On the other hand, chemical deposition, i.e. electroplating deposit higher thickness in less time and at lower cost, becomes an alternative method for Au deposition. In this work, we present a detailed optimization for the electroplating-based fabrication of these metamaterials. We find that slightly acidic (6.0 < pH < 7.0) gold sulfite solution supports immersion deposition, which should be minimized to avoid uncontrolled Au deposition. Immersion deposition leads to plate-like (for smaller radius AuNR) or capped-like, i.e. mushroom (for higher radius AuNR) structure formation. The electroplating time and DC supply are the tuning parameters that decide the geometry of the vertically aligned AuNR array in area-dependent electroplating deposition. This work will have implications for developing plasmonic metamaterial-based sensors.

Long-term survivable liposomes in seawater.

Molecular robotics is a research topic to develop a bio-molecular device that can equip sensors, circuits, and actuators. One of the objectives for this is to work them in various biological environments. Liposome-type molecular robot (liposome robot) can encapsulate chemicals and has high biocompatibility, so it is expected to use them in those environments. However, the robot is hardly implemented due to the lack of stability. In this study, we proposed that stable liposomes work in seawater as an example of implementation. To improve the stability, we considered the use of polyethylene glycol-modified lipids (PEG-modified lipids). PEGs immobilized on the substrate are known to form two conformations, a mushroom and a brush, depending on the density. At low density, PEGs form mushroom structures because there are plenty of spaces on the lipid membrane. When the distance between PEG chains is beyond the Flory radius of the grafted PEG, adjacent PEGs try to leave a space between each other. This results in the conformational change of PEGs to brush. We hypothesized that the kind and conformational differences affect liposome stability. We here focused on two PEG-modified lipids; lipid-PEG2000 (PEG2000) and lipid-PEG5000 (PEG5000). We prepared four types of liposomes in seawater; (1) without, with (2) PEG2000, (3) PEG5000, and (4) the 1:1 mixture of PEG2000 and PEG5000. For each PEG condition, we prepared sub-types of the liposomes which were expected to form brush and mushroom conformations. We microscopically observed them and evaluated the survival rate for two weeks after preparation. For each brush PEG condition, the average survival rate was more than 10% for 14 days. Opposite this, the rate was less than 10% in the other conditions. Based on them, we attempted to define the optimized condition for stable liposomes in seawater.

Wall temperature effects on the hypersonic boundary-layer transition over an inclined, blunt cone

Wall temperature is a crucial factor for the transition of hypersonic boundary layers. This paper investigates the wall temperature effects on the hypersonic boundary-layer transition over an inclined blunt cone with two wall temperatures by direct numerical simulations and instability analysis. The breakdown processes of leeward streamwise vortices and crossflow vortices are both studied. Inner modes with lower phase velocities and outer modes with higher phase velocities are responsible for the breakdown of leeward streamwise vortices, respectively, in cooled- and heated-wall cases. A higher wall temperature will promote the boundary layer transition in the vicinity of the leeward centerline due to the collision of nearby crossflow vortices with the leeward mushroom structure, instead of by destabilizing inner and outer modes. In the crossflow-dominated region, the transition is triggered by the interaction between second modes and crossflow vortices for the cooled-wall case. Increasing the wall temperature will promote the transition in this region even though second modes are suppressed.

Low-Scattering Dipole Antenna Using Mushroom-Shaped Structure for Applications in Dual-Band Shared-Aperture Array

A low-scattering dipole antenna by loading mushroom-shaped electromagnetic structures is proposed and employed to design an aperture-shared antenna array with low blockage effect. The arm of the proposed dipole element consists of a square ring and a short branch, and the mushroom structure is loaded on the arm to realize low scattering characteristics. The low scattering low band (LB) element is used for a dual-band shared-aperture array; the results indicate the pattern distortion of the high band (HB) array caused by the LB element can be greatly reduced accordingly. Compared with HB antenna alone, the simulated maximum gain decrease is 1.55 dB and the maximum beamwidth deviation is 27.4° after adding the reference LB dipole without loading the mushroom-shaped structure. Meanwhile the two values are reduced to 0.55 dB and 6.4°, respectively, after the mushroom-shaped structure is loaded. For demonstration, an aperture-shared antenna array operating in the LB of 0.698–0.96 GHz and the HB of 3.4–3.8 GHz is designed and fabricated. The measured results show that the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">S</i> -parameters and the pattern of the HB subarray with the proposed LB dipole change slightly, indicating that the proposed LB dipole can effectively suppress the scattering on the HB antenna. The results indicate the proposed design is suitable for multiband aperture-shared antennas in modern communication systems.

Surface Wave Suppression for Improved Isolation and Bore-Sight Gain Based on Dipole Moment Conversion

This article proposes a novel approach to surface wave suppression based on dipole moment conversion for isolation and bore-sight gain improvement. To transform the power associated with the surface wave into the source of the radiating wave, an inverted-L shape composed of a thin strip with a via post is adopted. Unlike the conventional mushroom structure, the via post is placed at the leading edge of the strip, so that the longitudinal edge of the strip is aligned with the propagation direction of the surface wave. This inverted-L structure plays a key role in converting the vertical electric dipole moment to the horizontal component, and the conversion efficiency can be further improved by arranging the structure with a narrower interval of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.057\lambda $ </tex-math></inline-formula> in the axis perpendicular to the propagation direction. For validation, multipole moments are calculated from induced currents, and the proposed metasurface is fabricated for two array configurations. Scattering parameters and near- and far-fields are measured to demonstrate the proposed approach experimentally. The fabricated metasurface shows an operating frequency band from 9.74 to 10.62 GHz, and its average isolation and bore-sight gain are improved by 6.3 and 1.6 dB, respectively, without any severe distortion on impedance matching.