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In this paper, a new equivalent circuit of a rectangular dumbbell‐shaped defected ground structure (DGS) with an ideal transformer is proposed. The proposed circuit incorporates a parallel resistor in the DGS gap, enabling the extraction of the coupling coefficient of DGS occurring in the narrow line gaps. Both circuit simulations and measurements demonstrate excellent agreement, confirming excellent performance compared to the measured results. Unlike the conventional equivalent circuit, which consists only of the lumped element, this one has an accuracy of only DGS units. In the proposed circuit, an ideal transformer has higher accuracy for the DGS in parallel with a resistor. We observed that increasing the resistance of the parallel resistor on the DGS unit leads to a decrease in the coupling coefficient and, conversely, decreasing the resistance prompts an increase in the coupling coefficient. The goal of this study is to develop a new equivalent circuit for a DGS unit with the ideal transformer, especially to find the coupling coefficient that occurred in the DGS gap. Here, we analyzed that the structure of the DGS unit had a gap, and the coupling coefficient must be built into any value. To demonstrate the effectiveness of the proposed circuit, DGS was used to design and conduct fabrication and measurement. The advantages of the proposed circuit analysis of the DGS behavior can be used to develop the attenuation pole as a one‐pole low‐pass filter, paving the way for future applications and developments in microwave and RF circuit design. [ABSTRACT FROM AUTHOR]

This paper presents three design methods for acoustic wave (AW) filters: the direct conversion design method, the slope parameter method, and the band edge fitting method (BEFM). Since the conventional BVD model consists only of lumped elements and has accuracy only near the resonance frequency, an NM-BVD model capable of broadband modeling is proposed in this paper and used to design the filter. In the proposed BEFM, a systematically optimal filter method is used to design the AW filter, and each AW resonator is tuned to the filter prototype value to meet the desired specifications. Thus, the filter design time and the number of resonators can be efficiently improved, and the filter design time can be reduced compared with the direct conversion and slope parameter methods commonly used in filter design. To demonstrate the effectiveness of these design methods, the proposed methods were used to design and fabricate an N41 filter using scandium-doped aluminum nitride (ScAlN) resonators. The broadband capabilities of the filter were verified using BEFM. The design, fabrication, and measurement of a broadband filter that meets the requirements of the 5G N41 frequency band centered at 2.593 GHz with a bandwidth of 196 MHz have verified the filter fabricated using the proposed design method. The insertion loss is less than -3 dB in the target band and more than 30 dB out of band. In summary, the proposed BEFM provides an efficient and accurate method for designing AW filters. [ABSTRACT FROM AUTHOR]

Dear Editor, The exosome, a kind of extracellular vesicle with a diameter in the range of 50-200 nm, has been extensively investigated in treating various skin issues, such as skin aging mitigation and cutaneous wound healing stimulation, and atopic dermatitis (AD).[[1], [3]] Compared to stem cell therapy, advantageous properties, such as a long half-life, small size, favorable penetration, and low immunogenicity, make exosomes more favorable and beneficial.[4] Although exosomes have been extensively investigated for their application in skin damage repair, the only sources shown to be effective are those derived from mesenchymal stem cells (MSCs).[5] However, exosome isolation from MSCs accompanies multiple drawbacks, such as the time and effort required for MSC culture and expansion, the risk of contamination with red blood cells during the isolation process, neovascularization potential, diminished cell viability, and the extreme invasiveness of removing MSCs from bone marrow.[6] Therefore, finding an alternative cell source for exosome isolation has become imperative for the effective application of exosomes in the repair of dysfunctional skin. The absorbance was then measured at 540 nm using a spectrophotometer (Molecular Devices, San Jose, CA, USA). gl Exosome treatment increased the protein levels of skin permeability barrier biomarkers, compared to the control in HaCaT cells. To investigate the effects of DF exosomes on skin permeability barrier protection, we evaluated the expression levels of skin permeability barrier maintenance biomarkers in keratinocytes treated with 1-chloro-2,4-dinitrobenzene (DNCB). Hence, we evaluated the expression levels of skin permeability barrier maintenance biomarkers in keratinocytes treated with DNCB, a skin irritant, and inducer of dermatitis, including AD. [Extracted from the article]

Atopic dermatitis (AD), a chronic inflammatory disease, severely interferes with patient life. Human placenta extract (HPH; also known as human placenta hydrolysate) is a rich source of various bioactive substances and has widely been used to dampen inflammation, improve fatigue, exert anti-aging effects, and promote wound healing. However, information regarding HPH's incorporation in AD therapies is limited. Therefore, this study aimed to evaluate HPH's effective potential in treating AD using tumor necrosis factor (TNF)-α/interferon (IFN)-γ-stimulated human keratinocytes (HaCaT), immunized splenocytes, and a 2,4-dinitrochlorobenzene (DNCB)-induced AD mouse model. In TNF-α /IFN-γ-stimulated HaCaT cells, HPH markedly reduced the production of reactive oxygen species (ROS) and restored the expression of nuclear factor erythroid 2-related factor 2 (Nrf2), superoxide dismutase 1(SOD1), catalase, and filaggrin (FLG). HPH reduced interleukin (IL)-6; thymus- and activation-regulated chemokine (TARC); thymic stromal lymphopoietin (TSLP); and regulated upon activation, normal T cell expressed and presumably secreted (RANTES) levels and inhibited nuclear factor kappa B phosphorylation. Additionally, HPH suppressed the T helper 2 (Th2) immune response in immunized splenocytes. In the AD-like mouse model, it significantly mitigated the DNCB-induced elevation in infiltrating mast cells and macrophages, epidermal thickness, and AD symptoms. HPH also reduced TSLP levels and prevented FLG downregulation. Furthermore, it decreased the expression levels of IL-4, IL-5, IL-13, TARC, RANTES, and immunoglobulin E (IgE) in serum and AD-like skin lesion. Overall, our findings demonstrate that HPH effectively inhibits AD development and is a potentially useful therapeutic agent for AD-like skin disease.