Characteristics of low-temperature plasma for activation of plastic-degrading microorganisms.

Plastic pollution is a problem that threatens the future of humanity, and various methods are being researched to solve it. Plastic biodegradation using microorganisms is one of these methods, and a recent study reported that plastic-degrading microorganisms activated by plasma increase the plastic decomposition rate. In contrast to microbial sterilization using low-temperature plasma, microbial activation requires a stable plasma discharge with a low electrode temperature suitable for biological samples and precise control over a narrow operating range. In this study, various plasma characteristics were evaluated using SDBD (Surface Dielectric Barrier Discharge) to establish the optimal conditions of plasma that can activate plastic-degrading microorganisms. The SDBD electrode was manufactured using low-temperature co-fired ceramic (LTCC) technology to ensure chemical resistance, minimize impurities, improve heat conduction, and consider freedom in designing the electrode metal part. Plasma stability, which is important for microbial activation, was investigated by changing the frequency and pulse width of the voltage applied to the electrode, and the degree of activation of plastic-degrading microorganisms was evaluated under each condition. The results of this study are expected to be used as basic data for research on the activation of useful microorganisms using low-temperature plasma.

Antenna Array Design Based on Low-Temperature Co-Fired Ceramics.

With the continuous development of wireless communication technology, the frequency band of 6G communication systems is moving towards higher frequencies such as millimeter waves and terahertz. In such high-frequency situations, wireless transmission requires antenna modules to be provided with characteristics of miniaturization, high integration, and high gain, which presents new challenges to the development of antenna technology. In this article, a 4 × 4 antenna array using multilayered low-temperature co-fired ceramic is proposed, operating in W-band, with a feeding network based on substrate-integrated waveguide, and an antenna element formed through the combination of a substrate-integrated cavity and surface parasitic patches, which guaranteed the array to possess the advantages of high integration and high gain. Combined with the substrate-integrated waveguide to a rectangular waveguide transition structure designed in the early stage, a physical array with a standard metal rectangular waveguide interface was fabricated and tested. The test results show that the gain of the antenna array is higher than 18 dBi from 88 to 98 GHz, with a maximum of 20.4 dBi.

Dielectric Properties of Materials Used for Microwave-Based NOx Gas Dosimeters.

Nitrogen oxides (NOx), primarily generated from combustion processes, pose significant health and environmental risks. To improve the coordination of measures against excessive NOx emissions, it is necessary to effectively monitor ambient NOx concentrations, which requires the development of precise and cost-efficient detection methods. This study focuses on developing a microwave- or radio frequency (RF)-based gas dosimeter for NOx detection and addresses the optimization of the dosimeter design by examining the dielectric properties of LTCC-based (Low-Temperature Co-fired Ceramics) sensor substrates and barium-based NOx storage materials. The measurements taken utilizing the Microwave Cavity Perturbation (MCP) method revealed that these materials exhibit more pronounced changes in dielectric losses when storing NOx at elevated temperatures. Consequently, operating such a dosimeter at high temperatures (above 300 °C) is recommended to maximize the sensor signal. To evaluate their high-temperature applicability, LTCC substrates were analyzed by measuring their dielectric losses at temperatures up to 600 °C. In terms of NOx storage materials, coating barium on high-surface-area alumina resolved issues related to limited NOx adsorption in pure barium carbonate powders. Additionally, the adsorption of both NO and NO2 was enabled by the application of a platinum catalyst. The change in dielectric losses, which provides the main signal for an RF-based gas dosimeter, only depends on the stored amount of NOx and not on the specific type of nitrogen oxide. Although the change in dielectric losses increases with the temperature, the maximum storage capacity of the material decreases significantly. In addition, at temperatures above 350 °C, NOx is mostly weakly bound, so it will desorb in the absence of NOx. Therefore, in the future development of a reliable RF-based NOx dosimeter, the trade-off between the sensor signal strength and adsorption behavior must be addressed.

Preparation of Sol-Gel-Derived CaO-B2O3-SiO2 Glass/Al2O3 Composites with High Flexural Strength and Low Dielectric Constant for LTCC Application.

Low-temperature co-fired ceramic (LTCC) substrate materials are widely applied in electronic components due to their excellent microwave dielectric properties. However, the absence of LTCC materials with a lower dielectric constant and higher mechanical strength restricts the creation of integrated and minified electronic devices. In this work, sol-gel-derived CaO-B2O3-SiO2 (CBS) glass/Al2O3 composites with high flexural strength and low dielectric constant were successfully prepared using the LTCC technique. Among the composites sintered at different temperatures, the composites sintered at 870 °C for 2 hours possess a dielectric constant of 6.3 (10 GHz), a dielectric loss of 0.2%, a flexural strength of 245 MPa, and a CTE of 5.3 × 10-6 K-1, demonstrating its great potential for applications in the electronic package field. By analyzing the CBS glass' physical characteristics, it was found that the sol-gel-derived glass has an extremely low dielectric constant of 3.6 and does not crystallize or react with Al2O3 at the sintering temperature, which is conducive to improving the flexural strength and reducing the dielectric constant of CBS glass/Al2O3 composites.

Pharmacological or genetic inhibition of LTCC promotes cardiomyocyte proliferation through inhibition of calcineurin activity.

Cardiomyocytes (CMs) lost during ischemic cardiac injury cannot be replaced due to their limited proliferative capacity, which leads to progressive heart failure. Calcium (Ca2+) is an important signal transducer that regulates key cellular processes, but its role in regulating CM proliferation is incompletely understood. A drug screen targeting proteins involved in CM calcium cycling in human embryonic stem cell-derived cardiac organoids (hCOs) revealed that only the inhibition of L-Type Calcium Channel (LTCC), but not other Ca2+ regulatory proteins (SERCA or RYR), induced the CM cell cycle. Furthermore, overexpression of Ras-related associated with Diabetes (RRAD), an endogenous inhibitor of LTCC, induced CM cell cycle activity in vitro, in human cardiac slices, and in vivo. Mechanistically, LTCC inhibition by RRAD induces the cell cycle in CMs by modulating calcineurin activity and translocating Hoxb13 to the CM nucleus. Together, this represents a robust pathway for regenerative strategies.

[Nimodipine in treatment of bipolar disorder]. / Primenenie nimodipina v terapii bipolyarnogo affektivnogo rasstroistva.

The purpose of this review is to correlate current data on the molecular mechanisms of action of the drug Nimodipine with its clinical effects and applicability in mental disorders belonging to the spectrum of affective pathology. The article discusses the prospects for using the calcium channel blocker nimodipine as a method of both mono and combination therapy for bipolar disorders with various types of course. Nimodipine is a selective blocker of voltage-dependent calcium channels, a dihydropyridine derivative. By blocking L type calcium channels, it prevents the entry of calcium ions into the cell. Due to its pronounced ability to penetrate the blood-brain barrier, it has a selective effect on brain neurons and has a vasodilating, antihypertensive and normotimic effect. Nimodipine blocks LTCC channels in brain neurons, thereby influencing synaptic plasticity, transmitter release and excitation-transcription coupling, which makes it possible to influence various clinical conditions with pathology in the area of affect, including bipolar disorders with ultra-rapid cycling, and also, in cases with high resistance and intolerance to other mood stabilizers.

Structural basis for human Cav1.2 inhibition by multiple drugs and the neurotoxin calciseptine.

Cav1.2 channels play crucial roles in various neuronal and physiological processes. Here, we present cryo-EM structures of human Cav1.2, both in its apo form and in complex with several drugs, as well as the peptide neurotoxin calciseptine. Most structures, apo or bound to calciseptine, amlodipine, or a combination of amiodarone and sofosbuvir, exhibit a consistent inactivated conformation with a sealed gate, three up voltage-sensing domains (VSDs), and a down VSDII. Calciseptine sits on the shoulder of the pore domain, away from the permeation path. In contrast, when pinaverium bromide, an antispasmodic drug, is inserted into a cavity reminiscent of the IFM-binding site in Nav channels, a series of structural changes occur, including upward movement of VSDII coupled with dilation of the selectivity filter and its surrounding segments in repeat III. Meanwhile, S4-5III merges with S5III to become a single helix, resulting in a widened but still non-conductive intracellular gate.

Research on Processability and Transmission Performance of Low Temperature Co-Fired Ceramic Ball Grid Array Packaging Based on Electroless Plating Surface Modification for Microwave Transceiver Circuits.

A microwave transmitter/receiver using the low-temperature co-fired ceramic substrate and ball grid array packaging demonstrates superior properties, including high integration, miniaturization, and high electromagnetic shielding. However, it holds limitations of inadequate hermeticity (that is, gas or moist impermeability), high cost, and low reproducibility. In this work, we aim to overcome these difficulties by introducing a new packing technique. The packaging utilizes an electroless plated Ni/Pd/Au surface, resulting in a significant enhancement of the packaging hermeticity by orders of magnitude, approaching the level of <5 × 10-9 Pa·m3/s. Both Sn63Pb37 and Au80Sn20 solder alloys demonstrate exceptional solderability, attributed to Pd atoms diffusing to the Au layer during soldering at 310 °C. A reliability test of the packaging shows that the shear strength of the solder balls drops after thermal shocks but negligibly affects the hermeticity of the packaging. Furthermore, a meticulously designed internal vertical interconnect structure and I/O interconnections were engineered in the ball grid array packaging, showcasing excellent transmission characteristics within the 10-40 GHz frequency range while ensuring effective isolation between ports.

Low-Permittivity and Low-Temperature Cofired BaSO4-BaF2 Microwave Dielectric Ceramics for High-Reliability Packaged Electronics.

In developing low-temperature cofired ceramic (LTCC) technology for high-density packaging or advanced packaged electronics, matching the coefficient of thermal expansion (CTE) among the packaged components is a critical challenge to improve reliability. The CTEs of solders and organic laminates are usually larger than 16.0 ppm of °C1-, while most low-permittivity (εr) dielectric ceramics have CTEs of less than 10.0 ppm °C1-. Therefore, a good CTE match between organic laminates and dielectric ceramics is required for further LTCC applications. In this paper, we propose a high-CTE BaSO4-BaF2 LTCC as a potential solution for high-reliability packaged electronics. The BaSO4-BaF2 ceramics have the advantages of a wide low-temperature sintering range (650-850 °C), low loss, temperature stability, and Ag compatibility, ensuring excellent performance in LTCC technology. The 95 wt %BaSO4-5 wt %BaF2 ceramic has a εr of 9.1, a Q × f of 40,100 GHz @11.03 GHz (Q = 1/tan δ), a temperature coefficient of the resonant frequency of -11.2 ppm °C1-, a CTE of +21.8 ppm °C1-, and a thermal conductivity of 1.3 W mK-1 when sintered at 750 °C. Furthermore, a dielectric resonant antenna using BaSO4-BaF2 ceramics, a typically packaged component of LTCC and laminate, was designed and used to verify the excellent performance by a gain of 6.0 dBi at a central frequency of 8.97 GHz and a high radiation efficiency of 90% over a bandwidth of 760 MHz. Good match and low thermal stress were found in the packaged components of BaSO4-BaF2 ceramics, organic laminates, and Sn-based solders by finite element analysis, proving the potential of this LTCC for high-reliability packaged electronics.

Current updates on arrhythmia within Timothy syndrome: genetics, mechanisms and therapeutics.

Timothy syndrome (TS), characterised by multiple system malfunction especially the prolonged corrected QT interval and synchronised appearance of hand/foot syndactyly, is an extremely rare disease affecting early life with devastating arrhythmia. In this work, firstly, the various mutations in causative gene CACNA1C encoding cardiac L-type voltage-gated calcium channel (LTCC), regard with the genetic pathogeny and nomenclature of TS are reviewed. Secondly, the expression profile and function of CACNA1C gene encoding Cav1.2 proteins, and its gain-of-function mutation in TS leading to multiple organ disease phenotypes especially arrhythmia are discussed. More importantly, we focus on the altered molecular mechanism underlying arrhythmia in TS, and discuss about how LTCC malfunction in TS can cause disorganised calcium handling with excessive intracellular calcium and its triggered dysregulated excitation-transcription coupling. In addition, current therapeutics for TS cardiac phenotypes including LTCC blockers, beta-adrenergic blocking agents, sodium channel blocker, multichannel inhibitors and pacemakers are summarised. Eventually, the research strategy using patient-specific induced pluripotent stem cells is recommended as one of the promising future directions for developing therapeutic approaches. This review updates our understanding on the research progress and future avenues to study the genetics and molecular mechanism underlying the pathogenesis of devastating arrhythmia within TS, and provides novel insights for developing therapeutic measures.

Miniaturized On-Ground 2.4 GHz IoT LTCC Chip Antenna and Its Positioning on a Ground Plane.

This paper presents a very low-profile on-ground chip antenna with a total volume of 0.075λ0× 0.056λ0× 0.019λ0 (at f0 = 2.4 GHz). The proposed design is a corrugated (accordion-like) planar inverted F antenna (PIFA) embedded in low-loss glass ceramic material (DuPont GreenTape 9k7 with ϵr = 7.1 and tanδ = 0.0009) fabricated with LTCC technology. The antenna does not require a clearance area on the ground plane where the antenna is located, and it is proposed for 2.4 GHz IoT applications for extreme size-limited devices. It shows a 25 MHz impedance bandwidth (for S11 < -6 dB), which means a relative bandwidth of 1%). A study in terms of matching and total efficiency is performed for several size ground planes with the antenna installed at different positions. The use of characteristic modes analysis (CMA) and the correlation between modal and total radiated fields is performed to demonstrate the optimum position of the antenna. Results show high-frequency stability and a total efficiency difference of up to 5.3 dB if the antenna is not placed at the optimum position.

Flow-based green ceramics microdevice with smartphone image colorimetric detection for free chlorine determination in drinking water.

The residual free chlorine concentration is an important parameter to evaluate the potability of water and the efficiency of disinfection in the water treatment system. As a restricted range of residual free chlorine concentration at all points of the distribution network is needed to ensure efficiency and to avoid deleterious effects, fast and in situ quantification of this specie is important. This work deals with the development and validation of two procedures based on DPD (N,N-diethyl-p-phenylenediamine) and OT (ortho-tolidine, 3,3-dimethylbenzidine) for the determination of residual free chlorine in water by exploiting a flow-based microdevice built with Low Temperature Co-Fired Ceramic (LTCC) technology. The analytical signal was monitored by a smartphone camera through RGB values obtained by a free application (Color Grab®). Under optimized conditions, linear ranges within 0.6-2.5 mg/L and 0.1-2.3 mg/L were obtained for DPD and OT methods, with limits of detection and quantification of 0.023 and 0.077 mg/L (DPD) and 0.026 and 0.089 mg/L (OT). Precision expressed as RSD (2.0 mg/L free chlorine, n = 10), was 1.3 % and 0.7 %, respectively. Both procedures were successfully applied to the analysis of samples from a water treatment plant. The flow-based microdevice coupled to digital-image colorimetry is an innovative, sustainable, and cost-effective analytical tool for in-field chemical analysis.

Modulation of L-type calcium channels in Alzheimer's disease: A potential therapeutic target.

Calcium plays a fundamental role in various signaling pathways and cellular processes in the human organism. In the nervous system, voltage-gated calcium channels such as L-type calcium channels (LTCCs) are critical elements in mediating neurotransmitter release, synaptic integration and plasticity. Dysfunction of LTCCs has been implicated in both aging and Alzheimer's Disease (AD), constituting a key component of calcium hypothesis of AD. As such, LTCCs are a promising drug target in AD. However, due to their structural and functional complexity, the mechanisms by which LTCCs contribute to AD are still unclear. In this review, we briefly summarize the structure, function, and modulation of LTCCs that are the backbone for understanding pathological processes involving LTCCs. We suggest targeting molecular pathways up-regulating LTCCs in AD may be a more promising approach, given the diverse physiological functions of LTCCs and the ineffectiveness of LTCC blockers in clinical studies.

Synthesis and Characterization of Single-Phase α-Cordierite Glass-Ceramics for LTCC Substrates from Tuff.

Single-phase α-cordierite glass-ceramics for a low-temperature co-fired ceramic (LTCC) substrate were fabricated from tuff as the main raw material, using the non-stoichiometric formula of α-cordierite with excess MgO without adding any sintering additives. The sintering/crystallization behavior and the various performances of dielectric properties, thermal expansion, and flexural strength of the glass-ceramics were detected. The results indicated that only single-phase α-cordierite crystal was precipitated from the basic glass sintered at the range 875-950 °C, and µ-cordierite crystal was not observed during the whole sintering-crystallization process. The properties of glass-ceramics were first improved and then deteriorated with the increase in tuff content and sintering temperature. Fortunately, the glass-ceramics sintered at 900 °C with 45 wt.% tuff content possessed excellent properties: high densify (2.62 g∙cm-3), applicable flexural strength (136 MPa), low dielectric loss (0.010, at 10 MHz), low dielectric constant (5.12, at 10 MHz, close to α-cordierite), and suitable coefficients of thermal expansion (CTE, 3.89 × 10-6 K-1).

The Involvement of CaV1.2 in Estrogenic Modulation of Morphine Antinociception in Rats Under Uterine Cervix Pain.

BACKGROUND: Morphine is one of the preferred drugs for the clinical treatment of pain. Both clinical and preclinical studies have reported sexual dimorphism in morphine analgesia. Different circulating levels of estrogen could be involved in sex differences in response to morphine analgesia. In our previous research, we found that capsaicin injection into the cervix of rats caused acute visceral pain that could be relieved by morphine. The role of estrogen in morphine analgesia in rats under uterine cervix pain and its underlying mechanisms remain to be explored. OBJECTIVES: The present study aims to investigate the effect of estrogen on morphine analgesia and its underlying mechanism in rats under uterine cervix pain. STUDY DESIGN: Controlled animal study. SETTING: University laboratory. METHODS: First, we compared the analgesic effect of morphine in ovariectomized rats with uterine cervix pain with or without estrogen replacement. Then, the changes in the expression of opioid receptors and L-type voltage-gated calcium channels (L-type-VGCC, LTCC) at the spinal level were detected by real-time quantitative polymerase chain reaction. Finally, we investigated the effect of the manipulation of spinal LTCC (L-type CaV1.2 calcium channel, L-type CaV1.3 calcium channel) on the estrogen-mediated inhibition of morphine analgesia. RESULTS: Our study shows that morphine antinociception is  diminished in rats with uterine cervix pain that are treated with estrogen. Estrogen treatment increases the expression of spinal CaV1.2 and CaV1.3, while only anti-CaV1.2 treatment impaired estrogenic suppression of morphine antinociception. LIMITATIONS: More underlying mechanisms of the role of spinal CaV1.2 in modulating estrogen-mediated inhibition of morphine analgesia need to be explored in future research. CONCLUSIONS: This is the first evidence that spinal CaV1.2 is involved in estrogenic modulation of morphine antinociception in rats under uterine cervix pain. Our results will provide new ideas and references for estrogen-related differential prescription of opioids.

Impaired myocellular Ca2+ cycling in protein phosphatase PP2A-B56α KO mice is normalized by ß-adrenergic stimulation.

The activity of protein phosphatase 2A (PP2A) is determined by the expression and localization of the regulatory B-subunits. PP2A-B56α is the dominant isoform of the B'-family in the heart. Its role in regulating the cardiac response to ß-adrenergic stimulation is not yet fully understood. We therefore generated mice deficient in B56α to test the functional cardiac effects in response to catecholamine administration versus corresponding WT mice. We found the decrease in basal PP2A activity in hearts of KO mice was accompanied by a counter-regulatory increase in the expression of B' subunits (ß and γ) and higher phosphorylation of sarcoplasmic reticulum Ca2+ regulatory and myofilament proteins. The higher phosphorylation levels were associated with enhanced intraventricular pressure and relaxation in catheterized KO mice. In contrast, at the cellular level, we detected depressed Ca2+ transient and sarcomere shortening parameters in KO mice at basal conditions. Consistently, the peak amplitude of the L-type Ca2+ current was reduced and the inactivation kinetics of ICaL were prolonged in KO cardiomyocytes. However, we show ß-adrenergic stimulation resulted in a comparable peak amplitude of Ca2+ transients and myocellular contraction between KO and WT cardiomyocytes. Therefore, we propose higher isoprenaline-induced Ca2+ spark frequencies might facilitate the normalized Ca2+ signaling in KO cardiomyocytes. In addition, the application of isoprenaline was associated with unchanged L-type Ca2+ current parameters between both groups. Our data suggest an important influence of PP2A-B56α on the regulation of Ca2+ signaling and contractility in response to ß-adrenergic stimulation in the myocardium.

Selectively Metalizable Low-Temperature Cofired Ceramic for Three-Dimensional Electronics via Hybrid Additive Manufacturing.

With increasing interest in the rapid development of customized ceramic electronics, hybrid additive manufacturing (HAM) technology has become a competent alternative to traditional solutions such as printed circuit boards and cofired ceramic technology. Herein, the novel HAM technology is proposed by combining a dispensing three-dimensional (3D) printing process and selectively laser-activated electroless plating for fabricating 3D fully functional ceramic electronic products. An appropriative 3D-printable and metalizable low-temperature cofired ceramic slurry is developed to build the green body of ceramic electronics. After the debinding and sintering process, the 3D ceramic structure can be selectively laser-activated and then electrolessly plated to achieve electronic functionality. The thickness of the plated copper layer approaches 10 µm after 4 h of plating, and the electrical conductivity is 5.5 × 107 S m-1, which is close to pure copper (5.8 × 107 S m-1). To reduce the surface roughness of the laser-activated ceramic surface and thereby enhance the conductivity of the copper layer, the laser parameters are optimized as a 1250 mm s-1 scan speed, a 0.4 W laser power, and a 20 kHz laser-spot frequency. A high-power 3D light-emitting diode circuit board with an internal cooling channel is successfully developed to prove the feasibility of this HAM technology for customizing fully functional 3D conformal ceramic electronics.

Enhanced Sinterability, Thermal Conductivity and Dielectric Constant of Glass-Ceramics with PVA and BN Additions.

With the rapid development of the microelectronics industry, many efforts have been made to improve glass-ceramics' sinterability, thermal conductivity, and dielectric properties, which are essential components of electronic materials. In this study, low-alkali borosilicate glass-ceramics with PVA addition and glass-BN composites were prepared and successfully sintered at 770 °C. The phase composition, density, microstructure, thermal conductivity, and dielectric constant were investigated. It was shown that PVA addition contributes to the densification process of glass-ceramics (~88% relative density, with closed/open pores in the microstructure) and improves the thermal conductivity of glass material from 1.489 to 2.453 W/K.m. On the other hand, increasing BN addition improves microstructures by decreasing porosities and thus increasing relative densities. A glass-12 wt. % BN composite sample exhibited almost full densification after sintering and presented apparent and open pores of 2.6 and 0.08%, respectively. A high thermal conductivity value of 3.955 W/K.m and a low dielectric constant of 3.00 (at 5 MHz) were observed in this material. Overall, the resulting glass-ceramic samples showed dielectric constants in the range of 2.40-4.43, providing a potential candidate for various electronic applications.

Effects of Organic Vehicle on the Rheological and Screen-Printing Characteristics of Silver Paste for LTCC Thick Film Electrodes.

Silver paste is widely used for low-temperature co-fired ceramic (LTCC) electrodes. In this work, a kind of LTCC silver paste for fine-line screen-printing was developed by considering the effect of the organic vehicle on rheological behavior and screen-printing properties. A step-by-step volatilization mode was applied to screen the mixed organic solvent of α-terpineol, 2-(2-butoxyethoxy) ethyl acetate (BCA) and dibutyl phthalate (DBP). The α-terpineol:BCA:DBP ratio of 5:2:3 is selected by considering the volatility, viscosity, and pseudoplasticity of the organic vehicle. Both viscosity and pseudoplasticity of shear-thinning increase with the increase of ethyl cellulose (EC) organic binder content. Three interval thixotropy test (3ITT) was conducted to discuss the thixotropy of silver paste. The minimum printing line width of 13.27 µm is obtained using silver paste with 10 wt% EC, confirming that the homemade paste has good printability.