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The cell membrane remodeling mediated by cyclopropane fatty acid synthase (CfaS) plays a crucial role in microbial physiological processes resisting various environmental stressors, including acid. Herein, we found a relatively high proportion (24.8%-28.3%) of cyclopropane fatty acid (CFA) Cy-19:0 in the cell membrane of a newly isolated extreme acidophile, Acidithiobacillus caldus CCTCC AB 2019256, under extreme acid stress. Overexpression of the CfaS encoding gene cfaS2 in Escherichia coli conferred enhanced acid resistance. GC–MS analysis revealed a 3.52-fold increase in the relative proportion of Cy-19:0 in the cell membrane of the overexpression strain compared to the control. Correspondingly, membrane fluidity, permeability and cell surface hydrophobicity were reduced to varying degrees. Additionally, HPLC analysis indicated that the overexpression strain had 1.54-, 1.42-, 1.85-, 1.20- and 1.05-fold higher levels of intracellular glutamic acid, arginine, aspartic acid, methionine and alanine, respectively, compared to the control. Overall, our findings shed light on the role of CfaS derived from extreme acidophile in bacterial defense against environmental acid stress, potentially facilitating its application in the design and development of industrial microbial chassis cells for organic acid production. [ABSTRACT FROM AUTHOR]

Acidithiobacillus caldus is a typical extreme acidophile widely used in the biohydrometallurgical industry, which often experiences extreme environmental stress in its natural habitat. Hfq, an RNA-binding protein, typically functions as a global regulator involved in various cellular physiological processes. Yet, the biological functions of Hfq derived from such extreme acidophile have not been extensively investigated. In this study, the recombinant strain Δhfq/Achfq, constructed by CRISPR/Cas9-mediated chromosome integration, fully or partially restored the phenotypic defects caused by hfq deletion in Escherichia coli, including impaired growth performance, abnormal cell morphology, impaired swarming motility, decreased stress resistance, decreased intracellular ATP and free amino acid levels, and attenuated biofilm formation. Particularly noteworthy, the intracellular ATP level and biofilm production of the recombinant strain were increased by 12.2% and 7.0%, respectively, compared to the Δhfq mutant. Transcriptomic analysis revealed that even under heterologous expression, AcHfq exerted global regulatory effects on multiple cellular processes, including metabolism, environmental signal processing, and motility. Finally, we established a potential working model to illustrate the regulatory mechanism of AcHfq in bacterial resistance to environmental stress. [ABSTRACT FROM AUTHOR]

Low‐temperature‐sintered Ni0.5Cu0.125Zn0.375Fe1.98O4 ferrites co‐added with x wt% (x = 0.00‐0.25 wt%) La2O3 and 0.25 wt% Bi2O3 were successfully prepared via conventional solid‐phase reaction method. The phase composition, microstructure, magnetic properties, and especially power loss variation of the samples were systematically studied. The results showed that all samples possessed a single spinel phase structure at a sintering temperature of 900°C, exhibiting high degree of densification and uniform grains. The appropriate amount of La2O3 additive improved the saturation flux density and permeability of NiCuZn ferrites, simultaneously reducing the coercivity and power loss. The maximum permeability and the lowest power loss were achieved at x = 0.15 wt%. The corresponding sample had the homogeneous microstructure and excellent magnetic properties, being a promising low‐temperature co‐fired ferrite candidate for magnetic power components. [ABSTRACT FROM AUTHOR]

A series of Ba1.5Sr1.5Co2+xZrxFe24‐2xO41 hexaferrites (x = 0.00, 0.01, 0.03, 0.05, 0.07, and 0.09) were successfully prepared by the conventional solid‐state reaction method. It was found that as the Co2+ and Zr4+ ions entered the hexaferrite structure, the lattice parameters increased, whereas the relative density increased when x = 0.00‐0.03 and then decreased. A suitable amount of substitution increased the DC resistivity, reduced the magnetic and dielectric losses, and made the μ′$\mu ^{\prime}$ and ε′$\varepsilon ^{\prime}$ closer to each other. At x = 0.03, the relative density and DC resistivity of the samples reached their maxim. Besides, both the magnetic and dielectric losses were lowest within the frequency range of 10 MHz‐1 GHz. Meanwhile, the hexaferrite was impedance matched to free space, and the miniaturization factor was about 15. Therefore, this low‐loss ferrite with almost equal permeability and permittivity could be meaningful for antenna miniaturization and high‐frequency applications. [ABSTRACT FROM AUTHOR]

Co 2 Z, a magneto-dielectric ferrite, has the potential to be used in the study of antenna miniaturization. The solid-state reaction method was employed to synthesize a series of Ba 1.5 Sr 1.5 Co 2 Mn x Fe 23- x O 41 (x = 0.0–1.0) hexaferrites in this paper. The crystal structure, microstructure, magnetic and dielectric properties were tested and investigated. The Mn3+ substitution did not introduce a second phase; however, it did influence the magnetic moments, super-exchange interaction, and electron hopping of the hexaferrite. Consequently, the magnetic and dielectric properties were altered, resulting in a decrease in losses. The hexaferrite exhibits superior magneto-dielectric properties when x = 0.4, and the cut-off frequency exceeds 1 GHz. Additionally, both the magnetic and dielectric losses reach their minimum. The design and simulation of a rectangular patch antenna were conducted using Ba 1.5 Sr 1.5 Co 2 Mn 0.4 Fe 22.6 O 41. The results indicate that the patch antenna size was effectively reduced, and the return loss S 11 could reach −29.83 dB at 1 GHz. The proposed Mn3+ substituted Co 2 Z hexaferrite has the potential to be of value and use in the design of miniaturized antennas. • The magneto-dielectric properties of Co 2 Z are modulated by Mn3+ substitution. • A high-performance Ba 1.5 Sr 1.5 Co 2 Mn 0.4 Fe 22.6 O 41 ferrite was obtained. • Applying the hexaferrite to the simulation of a rectangular patch antenna. • Moderate Mn3+ ions substitution can reduce the losses of Co 2 Z hexaferrites. [ABSTRACT FROM AUTHOR]

A series of La and Cu co-doped high-density Z-type hexaferrites, namely Ba 3− x La x Co 2 Fe 24− x Cu x O 41 (x = 0.20–0.95 in steps of 0.15), were synthesized via solid-state reaction method. Phase composition, microstructure, static magnetic properties, and high-frequency magneto–dielectric properties were studied systematically. Results show that with the addition of La and Cu, initial Z-type phase gradually transforms into a combination of Z- and W-type phases, and grain size increases. Specific saturation magnetization of samples increases significantly with increasing x and reaches the maximum (σ s = 59.20 emu/g) at x = 0.95. Furthermore, high-frequency magnetic and dielectric properties are improved, with permeability μ ′ and permittivity ε′ becoming almost equal in 0.1–1 GHz band. In particular, the sample with x = 0.65 exhibits excellent Snoek's product, that is (μ ′ − 1) f r ≈ 23.14 GHz , normalized impedance μ ′ / ε ′ approaches 1, and miniaturization factor is around 13.45 (@500 MHz). In this case, dielectric loss tangent tan δ ε is less than 0.003 below 500 MHz, and frequency range in which magnetic quality factor Q is greater than 10 is significantly broadened, covering wide bandwidth from 10 to 580 MHz. Thus, these hexaferrite ceramics are significantly promising for application to microwave communications. [ABSTRACT FROM AUTHOR]

Ba 1.5 Sr 1.5 Co 2-x Zn x Fe 22 O 41 (x = 0,0.4,0.8,1.2,1.6,2.0) hexaferrites substituted by Zn were prepared via conventional solid-state reaction. The influences of Zn substitution content on phase formation, microstructure, and magnetic properties, especially high-frequency magnetic properties, were systematically investigated. Results indicate that, when sintering temperature is 1200 °C, pure ferrite phase of Co 2 Z is formed, and Zn2+ is successfully incorporated into the lattice. Appropriate amount of Zn substitution can improve the densification and saturation magnetization (M s) of Z-type ferrite, thereby effectively promoting permeability. However, due to limitations of Snoek's law, cut-off frequency is found to be reduced with Zn substitution. For x = 0.4, the sample exhibits both high permeability (up to 22.49) and high cut-off frequency (~900 MHz), with Snoek constant (μ i − 1) × f r reaching 19.337 GHz. Furthermore, magnetic loss for the sample with x = 0.4 is found to be low. It is anticipated that this material will have extensive application prospects for miniaturization and high frequency antenna applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Iron metabolism partners L. ferriphilum / Acidiphilium sp. was isolated from bioheap. • Iron metabolism was accelerated by microbial cooperation in chalcocite bioleaching. • Cellulosic waste was further used to improve cell growth of Acidiphilium sp. • The community of iron metabolism partners was optimized in middle and later stage. • The final Cu2+ concentration in chalcocite bioleaching was improved by 43.8 %. The iron metabolism partners Leptospirillum ferriphilum and Acidiphilium sp. were screened from industrial bioheap site. An integrated multi-stage strategy was proposed to improve chalcolite column bioleaching coupling with synergistical utilization of cellulosic waste such as acid hydrolysate of aquatic plants. L. ferriphilum was used to accelerate the initial iron metabolism, and Acidithiobacillus caldus maintained a lower pH in the middle stage, while Acidiphilium sp. greatly inhibited jarosite passivation in the later stage. Meanwhile, L. ferriphilum (38.3 %) and Acidiphilium sp. (37.0 %) dominated the middle stage, while the abundance of Acidiphilium sp. reached 63.5 % in the later stage. The ferrous, sulfate ion and biomass were improved and the transcriptional levels of some biofilm and morphology related genes were significantly up-regulated. The final Cu2+ concentration reached 325.5 mg·L-1, improved by 43.8 %. Moreover, Canonical Correlation Analysis (CCA) analysis between bioleaching performance, iron/sulfur metabolism and community verified the important role of iron metabolism partners. [ABSTRACT FROM AUTHOR]

Ba 1.5 Sr 1.5 Co 1 Zn 1 Fe 23 O 41 hexaferrites added with x wt% Bi 2 O 3 were successfully prepared, and their phase composition, microstructure, and high-frequency magnetic and dielectric properties were investigated. The results show that the Bi 2 O 3 additive leads to the formation of the W-type ferrite phase and a subsequent increase in its proportion, which affects the magnetic and dielectric properties of Z-type hexaferrites. This effect can be explained by the effective medium theory. Furthermore, Bi 2 O 3 additives improve the compactness and reduces the grain size. The permeability and permittivity of the samples decrease, but the magnetic and dielectric losses are successfully reduced. For x = 1.5 wt%, the samples have a similar permeability and permittivity, a large miniaturization factor (∼18), a cut-off frequency of about 0.9 GHz, and considerably reduced magnetic and dielectric losses. An appropriate amount of Bi 2 O 3 additive improves numerous properties of the Ba 1.5 Sr 1.5 Co 1 Zn 1 Fe 23 O 41 ferrite, making it a more suitable material for high-frequency miniaturized antennas. • The appropriate amount of Bi 2 O 3 additives can improve numerous properties of the Z-type hexaferrite. • Excellent magnetic and dielectric properties can be obtained by adding 1.5 wt% Bi 2 O 3 in the Ba 1.5 Sr 1.5 Co 1 Zn 1 Fe 23 O 41 ferrite. • This composite hexaferrite with low losses can meet the requirements on miniaturization and broadband antenna applications. [ABSTRACT FROM AUTHOR]

A series of the Ba 1.5 Sr 1.5 Co 2- x Mn x Fe 23 O 41 (x = 0.0–0.5) hexaferrites was prepared by the conventional solid-state reaction method. The crystalline phase structure, microstructure and magneto-dielectric properties of samples were investigated. Z-type and W-type phases were detected in hexaferrites sintered at 1200 °C. Mn substitution can reduce the content of the second phase, changes the ion occupancy, magnetic moment, and electron hopping in hexaferrite. Therefore, the magnetic, DC resistivity, and dielectric properties were altered, and the losses were successfully reduced in the substituted samples. Particularly, the Ba 1.5 Sr 1.5 Co 1.8 Mn 0.2 Fe 23 O 41 hexaferrite has a more homogeneous crystal phase; its μ i is 18.5, f r exceeds 1 GHz, and the Snoek's constant reaches 18.55 GHz. At the same time, this hexaferrite were characterized by a relatively large magnetic quality factor and low dielectric losses (tan δ ε <0.05 below 500 MHz). This Z-type hexaferrite has excellent high-frequency magneto-dielectric properties and holds a potential for use in miniature antennas. • The results show that appropriate Mn substitution can increase the permeability, permittivity and Snoek's constant, and lower the magnetic and dielectric losses of Co 2 Z hexaferrites. • Favorable magneto-dielectric properties were obtained in the Ba 1.5 Sr 1.5 Co 1.8 Mn 0.2 Fe 23 O 41 hexaferrite. Its μ i is 18.5, Snoek's constant reaches 18.55 GHz, ε' around 16, and losses are low. • This ferrite can meet the requirements of miniaturized antennas. [ABSTRACT FROM AUTHOR]

A capillary electrophoresis method has been developed and validated to evaluate the stereospecific activity of recombinant human methionine sulfoxide reductase enzymes employing the C-terminally dinitrophenyl-labeled N -acetylated pentapeptide ac-KIFM(O)K-Dnp as substrate (M(O) = methionine sulfoxide). The separation of the ac-KIFM(O)K-Dnp diastereomers and the reduced peptide ac-KIFMK-Dnp was optimized using experimental design with regard to the buffer pH, buffer concentration, sulfated β-cyclodextrin and 15-crown-5 concentration as well as capillary temperature and separation voltage. A fractional factorial response IV design was employed for the identification of the significant factors and a five-level circumscribed central composite design for the final method optimization. Resolution of the peptide diastereomers as well as analyte migration time served as responses in both designs. The resulting optimized conditions included 50 mM Tris buffer, pH 7.85, containing 5 mM 15-crown-5 and 14.3 mg/mL sulfated β-cyclodextrin, at an applied voltage of 25 kV and a capillary temperature of 21.5 °C. The assay was subsequently applied to the determination of the stereospecificity of recombinant human methionine sulfoxide reductases A and B2. The Michaelis–Menten kinetic data were determined. The pentapeptide proved to be a good substrate for both enzymes. Furthermore, the first separation of methionine sulfoxide peptide diastereomers is reported. [ABSTRACT FROM AUTHOR]

Phase formation, microstructure, magnetic properties, and dielectric properties of Ba 1.5 Sr 1.5 Co 2 Fe (23 − x) Cr x O 41 (0.0 ≤ x ≤ 1.0) ceramics, in which Fe3+ ions were substituted by Cr3+ ions, were systematically investigated. X-ray diffraction results reveal that Z-type hexagonal ferrite was formed by sintering at 1250 °C, and Cr3+ ions successfully enter lattice without destroying crystal structure. Analysis of the microstructure reveals that Cr3+ ion doping has significant effect on crystal micromorphology. Samples with x = 0.4 have the most homogeneous micromorphology and the highest sintering density of 5.12 g/cm3. In addition, under the influence of external magnetic field, all samples exhibit typical soft magnetic character and hysteresis characteristics, with saturation magnetization up to 63.86 emu/g (x = 0.6). Particularly, compared with undoped sample, Cr-doped samples have outstanding magnetic–dielectric properties. Firstly, with increasing Cr3+ amount, real part of the permeability (μ ′) reaches the maximum value of 10.70 at x = 0.4, while cutoff frequency exceeds 2 GHz, and Snoek constant reaches ∼19.50 GHz. Furthermore, due to more homogeneous microstructure, samples with x = 0.4 have low magnetic loss and can maintain high quality factor (Q) over a broad frequency range. Moreover, real part of the permittivity (ε ′) reaches the maximum value of 16.90 at x = 0.6, and dielectric loss remains lower than 0.013 for frequencies below 0.7 GHz. Consequently, magnetic–dielectric materials prepared in this work are expected to have extensive application prospects for ultrahigh-frequency devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mn2+ and Nb5+ incorporated in the lattice of NiCuZn ferrite modify the cation distribution, affecting magnetocrystalline anisotropy constant and causing a decrease in Δ H. • Mn2+ and Nb5+ incorporated in the lattice of NiCuZn ferrite increase the dielectric constant of NiCuZn ferrite, beneficial to miniaturization of microwave circulator. • The MnNb-NiCuZn ferrite possesses excellent gyromagnetic properties (ΔH = 129 Oe, 4π M s = 4577 G, ε' = 15.4@100 MHz). Ni 0.42-x/3 Nb x /3 Cu 0.18 Zn 0.4 Mn x Fe 1.98− x O 4− δ (x = 0–0.1) materials, possessing a high saturation magnetization, high dielectric constant, and narrow ferromagnetic resonance linewidth, were prepared via the solid-phase reaction method. The cation distribution, as well as the dielectric and gyromagnetic properties, were studied in detail. Mn2+ and Nb5+ incorporated in the lattice occupy tetrahedral site, causing the redistribution of cation and the reduction of A–B superexchange interaction. This leads to an increase in saturation magnetization followed by a decrease. The introduction of appropriate amounts of Mn2+ and Nb5+ ions reduces the magnetocrystalline anisotropy constant | K 1 | and thus reduces the ferromagnetic resonance linewidth (ΔH). Furthermore, high polarisability of Mn2+ and Nb5+ causes the increase in the dielectric constant of the ferrites. At x = 0.08, excellent gyromagnetic and dielectric properties, including a high dielectric constant (ε ' = 15.4@100 MHz), high saturation magnetization (4π M s = 4577 G), and narrow ferromagnetic resonance linewidth (Δ H = 129 Oe@9.55 GHz) for the NiCuZn ferrite, was achieved. Finally, a K-band microstrip circulator operating at 20.8 to 28 GHz was designed. The simulation showed that the isolation of the circulator in the working frequency band is greater than 20 dB, showing the potential of the prepared ferrites in microwave circulators. [ABSTRACT FROM AUTHOR]

This work investigates the influence of niobium pentoxide (Nb 2 O 5) as dopant, on the structural, magnetic, and dielectric properties of NiZnCo ferrites. The results showed that Nb 2 O 5 was an effective dopant, and the Nb5+ ions entered the B site to replace Fe3+ ions, which altered the electromagnetic properties of the NiZnCo ferrite. In particular, the coercivity (H c) was 20∼24 Oe, and the magnetic quality factor (Q), was more than 200 at x = 0 and x = 0.1 wt%, which is 4∼5 times higher than that of NiZn and NiCuZn ferrites. Excellent electromagnetic properties were obtained for 0.1 wt% Nb 2 O 5 -doped NiZnCo ferrite, i.e. , M s = 88.3 emu/g, H c =20.4 Oe, ρ = 2.4 × 105 Ω m and Q = 202 @20 MHz. These excellent electromagnetic properties of Nb 2 O 5 -doped NiZnCo ferrites could be potentially applied to resonators and capacitors at high frequency. [ABSTRACT FROM AUTHOR]

A series of Mn-substituted Z-type hexaferrite ceramics (Ba 1.5 Sr 1.5 Co 2 Fe (23 - x) Mn x O 41 ; 0.0 ≤ x ≤ 0.5 at a step of 0.1) were prepared via double sintering method. According to EDS data, Mn3+ ions were uniformly distributed throughout the lattice. The relative densities of all samples were higher than 90%, enriching the maxima at x = 0.1 and x = 0.2 (above 95%), which indicated compact grain growth. The greatest saturation magnetization (56.18 emu/g) was achieved at x = 0.1 and then dropped with a further doping of Mn3+ ion, the coercivity showed the opposite trend. Moreover, both permeability and permittivity of the samples drastically changed with the increase of x. Particularly, the samples with x = 0.1–0.2 possessed close permeability (μ′) and permittivity (ε′), and they have relatively high miniaturization factors (n x=0.1 = 12.74, n x=0.2 = 10.38) in the frequency range 10 MHz to 1 GHz. Ba 1.5 Sr 1.5 Co 2 Fe 22.9 Mn 0.1 O 41 ceramics exhibits best microwave properties, μ′ = 11.26, ε′ = 14.42, magnetic loss tangent tan δ μ = 0.048, dielectric loss tangent tan δ ε = 0.0024, and Snoek constant = 17.433 GHz. Consequently, these Mn-substituted hexaferrite ceramics with impedance matching have great application potential for ultra-high frequency miniaturized antenna substrates. • The high-frequency magnetic-dielectric properties of Mn-substituted Z-type hexaferrite ceramics were systematically investigated. • The relative densities of all samples were higher than 90%, enriching the maxima at x = 0.1 and x = 0.2 (above 95%). • The x=0.1 sample exhibits best microwave properties with μ′ = 11.26, ε′ = 14.42, tanδ μ = 0.048, tanδ ε = 0.0024, and Snoek constant ~ 17.433 GHz. • The miniaturization factors of x = 0.1 and 0.2 samples were greater than 10 (n x=0.1 = 12.72, n x=0.2 = 10.35) in the frequency range 10 MHz to 1 GHz. [ABSTRACT FROM AUTHOR]

In this study, the microwave dielectric properties of Co2+‐substituted BaZnP2O7 ceramics prepared through conventional solid‐state synthesis were investigated. X‐ray diffraction, Rietveld refinement, energy‐dispersive spectroscopy, and Raman spectroscopy all indicated that BaZn1−xCoxP2O7 ceramics sintered at 875°C were composed of a single phase. The lattice strain and crystallite size were estimated using Williamson–Hall (W–H) method. Both the scanning electron microscopy images and density measurements showed that Co2+ ions had an effect on the grain growth and densification of ceramics. The microwave dielectric properties were influenced by the intrinsic and extrinsic factors that varied with the increase of x value. An optimal performance (εr = 7.62, Q × f = 600 45 GHz, and τf = −74 ppm/°C) was achieved at x =.01. The porosity and relative density played a significant role in the dielectric constant εr: the denser the ceramic structure, the larger the dielectric constant. The Q × f and τf values were negatively correlated with the full width at half maximum of the Raman vibrational peak at approximately 1049 cm−1. Moreover, the Q × f value was improved compared to that of the undoped BaZnP2O7 ceramics. Therefore, cobalt ion substitution is an effective strategy to enhance the performance of microwave dielectric ceramics. [ABSTRACT FROM AUTHOR]

Ba 0.8 Sr 0.2 CuSi 2 O 6 ceramics have a low dielectric constant, which is useful for low-latency 5G communication. To enable the preparation of Ba 0.8 Sr 0.2 CuSi 2 O 6 low-temperature co-fired ceramic (LTCC) materials, LBSCA and LBBS were used in this paper to reduce the sintering temperature of Ba 0.8 Sr 0.2 CuSi 2 O 6. The effects of LBSCA and LBBS on the phase composition, densification, microscopic morphology, and vibrational characteristics of the ceramics were investigated by X-ray diffraction, scanning electron microscopy, density measurements, and Raman spectroscopy, and the causal factors influencing the microwave dielectric properties with the addition of glass were analyzed. It was found that 0.4 wt% LBSCA glass and 1 wt% LBBS glass reduced the sintering temperature to 925 °C, and these prepared ceramics had excellent microwave dielectric properties. The ceramic prepared with 0.4 wt% LBSCA glass had an ε r value of 7.672, Q × f value of 37193 GHz, and τ f value of −14.93 ppm/°C, while the ceramic prepared with 1 wt% LBBS glass had an ε r value of 7.512, Q × f value of 32136 GHz, and τ f value of −13.92 ppm/°C. The phase composition of the ceramics did not significantly change, indicating that neither glass reacted with the ceramics. The ε r value was affected by both density and Raman shift, the trend in the Q × f values was consistent with the density, and the τ f value decreased with increasing glass content, which was attributed to the liquid phase generated by the glass in the ceramic. In addition, co-firing these glass-doped ceramics with Ag at a low temperature resulted in good chemical compatibility. Combined with the near-zero τ f , these results demonstrate the excellent promise of these two ceramics as alternative materials for LTCC microwave devices and their application in 5G communication. [ABSTRACT FROM AUTHOR]

New low loss and low-sintering temperature co-fired Ba 3- x Cu x Ti 4 Nb 4 O 21 (BCTN, 0 ≤ x ≤ 0.12) ceramics with 0.60 wt % Li 2 O-B 2 O 3 -SiO 2 -CaO-Al 2 O 3 (LBSCA) glass were prepared by solid-state reaction methodology. This work showed that CuO and LBSCA were effective sintering aid, which improved the densification and decreased sintering temperature. Thus, the excellent microwave dielectric properties of BCTN ceramics (x = 0.08) were obtained after sintering at 925 ℃ with ε r ~ 44.18, Q× f ~ 17,860 GHz (@ 5.6 GHz) and τ f ~ 94.76 ppm/℃. Q× f value was increased nearly 3-fold compared to pure BTN ceramics (~ 6090 GHz). Based on the P-V-L bond theory, the Ti-O and Nb-O bonds together contributed greatly to ε r. The Nb-O bonds was the main factor affecting the internal loss on Q× f. The τ f closely related to the oxygen octahedron [Ti1/Nb1O 6 ]. The BCTN ceramics would not react with Ag electrodes, and had great potential to be used in LTCC microwave devices. [ABSTRACT FROM AUTHOR]

• hUCMSC-Exo promotes the differentiation of CD4+IL-10+T cells. • hUCMSC-Exo suppresses ER stress of CD4+ T cells by transfer miR-16-5p. • hUCMSC-Exo suppresses apoptosis of CD4+ T cells. • hUCMSC-Exo alleviates oxidative stress and inflammatory response during GVHD. Exosomes generated from mesenchymal stem cells (MSCs) are thought to be a unique therapeutic strategy for several autoimmune deficiency illnesses. The purpose of this study was to elucidate the protective effects of human umbilical cord mesenchymal stem cell-derived exosomes (hUCMSC-Exo) on CD4+ T cells dysfunction during graft-versus-host disease (GVHD) and to identify the underlying processes involved. Here, we showed that hUCMSC-Exo treatment can effectively attenuate GVHD injury by alleviating redox metabolism disorders and inflammatory cytokine bursts in CD4+ T cells. Furthermore, hUCMSC-Exo ameliorate ER stress and ATF6/CHOP signaling-mediated apoptosis in CD4+ T cells and promote the development of CD4+IL-10+ T cells during GVHD. Moreover, downregulating miR-16-5p in hUCMSC-Exo impaired their ability to prevent CD4+ T cells apoptosis and weakened their ability to promote the differentiation of CD4+IL-10+ T cells. Collectively, the obtained data suggested that hUCMSC-Exo suppress ATF6/CHOP signaling-mediated ER stress and apoptosis in CD4+ T cells, enhance the differentiation of CD4+IL-10+ T cells, and reverse the imbalance of immune homeostasis in the GVHD process by transferring miR-16-5p. Our study provided further evidence that GVHD patients can benefit from hUCMSC-Exo-mediated therapy. [ABSTRACT FROM AUTHOR]

In this work, a new low loss Ba 3 Ti 4- x (Mn 1/3 Nb 2/3) x Nb 4 O 21 (MN-BTN, 0 ≤ x ≤ 12 mol%) ceramics configuration was presented through preparing by the solid-state route. The XRD patterns, Rietveld refinement, microstructure, and microwave properties were systematically analyzed. All the fabricated MN-BTN ceramics belonged to the hexagonal structure with a P 6 3 / mcm space group. More specifically, the 6MN-BTN ceramic exhibited a high relative density of ~92.3 %, homogeneous grains distribution with an average size of ~71.95 µm, and several excellent microwave dielectric properties: ε r = 59.67, Q× f = 16,226 GHz, τ f = +103.9 ppm/℃ sintered at 1220 ℃. The incorporation of 1.5 wt % BaCu(B 2 O 5) (BCB) compound within the 6MN-BTN ceramic not only effectively reduced the sintering temperature from 1220 ℃ to 950 ℃, but also the excellent microwave dielectric properties were maintained: ε r = 42.33, Q× f = 11,300 GHz, τ f = +24.7 ppm/℃. Interestingly, the 6MN-BTN + 1.5 wt % BCB ceramic showed better chemical compatibility with Ag. The proposed 6MN-BTN + 1.5 wt % BCB ceramic configuration could be regarded as a promising material for LTCC applications. • Adapting composite (Mn 1/3 Nb 2/3)4+ ions and adding BCB compound to realize low temperature co-firing BTN ceramics. • 6MN-BTN ceramic had excellent microwave dielectric properties: εr=59.67, Q×f=16226 GHz, τf=+103.9 ppm/℃ sintered at 1220℃. • Enhanced microwave properties were related to bulk density, uniform grain size, packing fraction, octahedral distortion. • BCB compound was an effective sintering aid, not only matched with Ag co-firing, but also validly improved τf. [ABSTRACT FROM AUTHOR]

• The edible quality of liquid egg after steaming, baking, frying and microwaving were compared. • Baked egg showed superior soft and elasticity taste characteristics. • Fried egg exhibited better antioxidant activity. • The texture of cooked eggs is closely related to their microstructure. The purpose of this study was to compare the edible quality of liquid egg after steaming, baking, frying and microwaving. Texture profile analysis (TPA) and color analysis were used to evaluate the sensory characteristics of cooked eggs. The fat, vitamin A and E, protein and amino acid content of cooked eggs and the antioxidant activity after in vitro digestion were determined to display the variations in nutritional value. TPA results demonstrate that baked egg exhibited a softer and more elasticity texture, with a significant lower hardness of 3234 g than fried and microwaved eggs (p < 0.05). This is also consistent with the results of cohesiveness and chewiness. Consequences from scanning electron microscope showed plentiful honeycomb structure in baked egg, which may be related to the soft and elasticity texture. However, significantly higher contents of fat, vitamins A and E, protein were determined in fried egg (p < 0.05), which may be related to its lower moisture content. The strongest free radical scavenging efficiency for the hydroxyl, the DPPH and the superoxide radical were found in the gastrointestinal digestion of fried egg, with the rate of 95.76%, 81.08%, and 91.08%, respectively. Overall, baked egg showed superior soft and elasticity taste characteristics due to its honeycomb structure, while fried egg exhibited better antioxidant activity because of its high contents in vitamins and amino acids. The above results provide potential approach for the manufacture of pre-cooked eggs and related products using liquid eggs as ingredients. [ABSTRACT FROM AUTHOR]