Gas Sensors Based on Semiconductor Metal Oxides Fabricated by Electrospinning: A Review.

Electrospinning has revolutionized the field of semiconductor metal oxide (SMO) gas sensors, which are pivotal for gas detection. SMOs are known for their high sensitivity, rapid responsiveness, and exceptional selectivity towards various types of gases. When synthesized via electrospinning, they gain unmatched advantages. These include high porosity, large specific surface areas, adjustable morphologies and compositions, and diverse structural designs, improving gas-sensing performance. This review explores the application of variously structured and composed SMOs prepared by electrospinning in gas sensors. It highlights strategies to augment gas-sensing performance, such as noble metal modification and doping with transition metals, rare earth elements, and metal cations, all contributing to heightened sensitivity and selectivity. We also look at the fabrication of composite SMOs with polymers or carbon nanofibers, which addresses the challenge of high operating temperatures. Furthermore, this review discusses the advantages of hierarchical and core-shell structures. The use of spinel and perovskite structures is also explored for their unique chemical compositions and crystal structure. These structures are useful for high sensitivity and selectivity towards specific gases. These methodologies emphasize the critical role of innovative material integration and structural design in achieving high-performance gas sensors, pointing toward future research directions in this rapidly evolving field.

Comprehensive Review of RF MEMS Switches in Satellite Communications.

The miniaturization and low power consumption characteristics of RF MEMS (Radio Frequency Microelectromechanical System) switches provide new possibilities for the development of microsatellites and nanosatellites, which will play an increasingly important role in future space missions. This paper provides a comprehensive review of RF MEMS switches in satellite communication, detailing their working mechanisms, performance optimization strategies, and applications in reconfigurable antennas. It explores various driving mechanisms (electrostatic, piezoelectric, electromagnetic, thermoelectric) and contact mechanisms (capacitive, ohmic), highlighting their advantages, challenges, and advancements. The paper emphasizes strategies to enhance switch reliability and RF performance, including minimizing the impact of shocks, reducing driving voltage, improving contacts, and appropriate packaging. Finally, it discusses the enormous potential of RF MEMS switches in future satellite communications, addressing their technical advantages, challenges, and the necessity for further research to optimize design and manufacturing for broader applications and increased efficiency in space missions. The research findings of this review can serve as a reference for further design and improvement of RF MEMS switches, which are expected to play a more important role in future aerospace communication systems.

The Latest Advances in Ink-Based Nanogenerators: From Materials to Applications.

Nanogenerators possess the capability to harvest faint energy from the environment. Among them, thermoelectric (TE), triboelectric, piezoelectric (PE), and moisture-enabled nanogenerators represent promising approaches to micro-nano energy collection. These nanogenerators have seen considerable progress in material optimization and structural design. Printing technology has facilitated the large-scale manufacturing of nanogenerators. Although inks can be compatible with most traditional functional materials, this inevitably leads to a decrease in the electrical performance of the materials, necessitating control over the rheological properties of the inks. Furthermore, printing technology offers increased structural design flexibility. This review provides a comprehensive framework for ink-based nanogenerators, encompassing ink material optimization and device structural design, including improvements in ink performance, control of rheological properties, and efficient energy harvesting structures. Additionally, it highlights ink-based nanogenerators that incorporate textile technology and hybrid energy technologies, reviewing their latest advancements in energy collection and self-powered sensing. The discussion also addresses the main challenges faced and future directions for development.

Design and Analysis of a Fluid-Filled RF MEMS Switch.

In the present study, a fluid-filled RF MEMS (Radio Frequency Micro-Electro-Mechanical Systems) switch is proposed and designed. In the analysis of the operating principle of the proposed switch, air, water, glycerol and silicone oil were adopted as filling dielectric to simulate and research the influence of the insulating liquid on the drive voltage, impact velocity, response time, and switching capacity of the RF MEMS switch. The results show that by filling the switch with insulating liquid, the driving voltage can be effectively reduced, while the impact velocity of the upper plate to the lower plate is also reduced. The high dielectric constant of the filling medium leads to a lower switching capacitance ratio, which affects the performance of the switch to some extent. By comparing the threshold voltage, impact velocity, capacitance ratio, and insertion loss of the switch filled with different media with the filling media of air, water, glycerol, and silicone oil, silicone oil was finally selected as the liquid filling medium for the switch. The results show that the threshold voltage is 26.55 V after filling with silicone oil, which is 43% lower under the same air-encapsulated switching conditions. When the trigger voltage is 30.02 V, the response time is 10.12 µs and the impact speed is only 0.35 m/s. The frequency 0-20 GHz switch works well, and the insertion loss is 0.84 dB. To a certain extent, it provides a reference value for the fabrication of RF MEMS switches.

UWB Frequency-Selective Surface Absorber Based on Graphene Featuring Wide-Angle Stability.

In this paper, an ultra-wideband and polarization-insensitive frequency-selective surface absorber is presented with oblique incident stable behavior. Different from conventional absorbers, the absorption behavior is much less deteriorated with the increase in the incidence angle. Two hybrid resonators, which are realized by symmetrical graphene patterns, are employed to obtain the desired broadband and polarization-insensitive absorption performance. The optimal impedance-matching behavior is designed at the oblique incidence of electromagnetic waves, and an equivalent circuit model is used to analyze and facilitate the mechanism of the proposed absorber. The results indicate that the absorber can maintain a stable absorption performance with a fractional bandwidth (FWB) of 136.4% up to 40°. With these performances, the proposed UWB absorber could be more competitive in aerospace applications.

Grape seed extract proanthocyanidin antagonizes aristolochic acid I-induced liver injury in rats by activating PI3K-AKT pathway.

Aristolochic acid is internationally recognized as a carcinogen. It has been shown that the main toxic mechanism of aristolochic acid on the liver and kidney is the induction of ROS-induced oxidative stress damage. To investigate whether proanthocyanidins (GSPE), a natural antioxidant product from grape seed extract, could antagonize AA-I-induced liver injury. Thirty-two SD rats were selected and divided into aristolochic acid exposure group (AA-I), normal control group, GSPE group and GSPE intervention group. The protective effects of GSPE on AA-I liver injury were evaluated by examining the body weight, liver index, liver function and liver pathological sections of rats. The results of body weight, liver index, liver function and liver pathological sections of rats showed that GSPE had antagonistic effects on AA-I-induced liver injury. antioxidant enzyme activity in the GSPE intervention group was significantly higher than that in the aristolochic acid group, apoptotic cells were significantly lower than that in the aristolochic acid group, protein and mRNA expression of PI3K-AKT and BCL-2 were significantly higher than that in the aristolochic acid group, BAX, The protein and mRNA expression of BAX, CASPAES-3, CASPAES-9 were significantly lower than those of the aristolochic acid group. GSPE can antagonize aristolochic acid-induced hepatotoxicity, and its mechanism of action is to antagonize aristolochic acid I-induced liver injury by inhibiting PI3K-AKT pathway-mediated hepatocyte apoptosis.

A New Segmented Virus Associated with Human Febrile Illness in China.

BACKGROUND: In 2017, surveillance for tickborne diseases in China led to the identification of a patient who presented to a hospital in Inner Mongolia with a febrile illness that had an unknown cause. The clinical manifestation of the illness was similar to that of tickborne encephalitis virus (TBEV) infection, but neither TBEV RNA nor antibodies against the virus were detected. METHODS: We obtained a blood specimen from the index patient and attempted to isolate and identify a causative pathogen, using genome sequence analysis and electron microscopy. We also initiated a heightened surveillance program in the same hospital to screen for other patients who presented with fever, headache, and a history of tick bites. We used reverse-transcriptase-polymerase-chain-reaction (RT-PCR) and cell-culture assays to detect the pathogen and immunofluorescence and neutralization assays to determine the levels of virus-specific antibodies in serum specimens from the patients. RESULTS: We found that the index patient was infected with a previously unknown segmented RNA virus, which we designated Alongshan virus (ALSV) and which belongs to the jingmenvirus group of the family Flaviviridae. ALSV infection was confirmed by RT-PCR assay in 86 patients from Inner Mongolia and Heilongjiang who presented with fever, headache, and a history of tick bites. Serologic assays showed that seroconversion had occurred in all 19 patients for whom specimens were available from the acute phase and the convalescent phase of the illness. CONCLUSIONS: A newly discovered segmented virus was found to be associated with a febrile illness in northeastern China. (Funded by the National Key Research and Development Program of China and the National Natural Science Foundation of China.).

Design and Analysis of the Capacitive RF MEMS Switches with Support Pillars.

Conventional parallel capacitive RF MEMS switches have a large impact during the suction phase. In general, RF MEMS switches have to be switched on and off in a considerably fast manner. Increasing the driving voltage enables fast switching but also increases the impact force, which causes the beam membrane to be prone to failure. In the present study, the addition of two support pillars was proposed for slowing down the fall of the beam membrane based on the conventional RF MEMS parallel switch, so as to reduce the impact velocity. As such, a novel RF MEMS switch was designed. Further, simulation software was used to scan and analyze the positioning and height of the support pillars with respect to electromechanical and electromagnetic performance. The simulation results show that the optimal balance of impact velocity and pull-in time was achieved at a height of 0.8 um, a distance of 10 um from the signal line, and an applied voltage of 50 V. The impact velocity was reduced from 1.8 m/s to 1.1 m/s, decreasing by nearly 40%. The turn off time increased from 3.9 us to 4.2 us, representing an increase of only 0.05%. The insertion loss was less than 0.5 dB at 32 GHz, and the isolation was greater than 50 dB at 40 GHz.

RNAi-mediated silencing of Trichinella spiralis glutaminase results in reduced muscle larval infectivity.

Trichinella spiralis is an important foodborne parasitic nematode distributed worldwide that infects humans and animals. Glutaminase (GLS) is an important gene in the glutamine-dependent acid resistance (AR) system; however, its role in T. spiralis muscle larvae (ML) remains unclear. The present study aimed to characterize T. spiralis GLS (TsGLS) and assess its function in T. spiralis ML AR both in vitro and in vivo using RNA interference. The results indicated that native TsGLS (72 kDa) was recognized by anti-rTsGLS serum at the muscle larvae stage; moreover, an immunofluorescence assay confirmed that TsGLS was located in the epidermis of ML. After silencing the TsGLS gene, the relative expression of TsGLS mRNA and the survival rate of T. spiralis ML were reduced by 60.11% and 16.55%, respectively, compared to those in the PBS and control groups. In vivo AR assays revealed that the worm numbers at 7 and 35 days post-infection (dpi) decreased by 61.64% and 66.71%, respectively, compared to those in the PBS group. The relative expression of TsGLS mRNA in F1 generation T. spiralis ML was reduced by 42.52%, compared to that in the PBS group. To the best of our knowledge, this is the first study to report the presence of the glutamine-dependent AR system in T. spiralis. Our results indicate that TsGLS plays a crucial role in the T. spiralis AR system; thus, it could be used as a potential candidate target molecule for producing vaccines against T. spiralis infection.

Comprehensive analysis of miRNA profiles reveals the role of Schistosoma japonicum miRNAs at different developmental stages.

Schistosomiasis is an important zoonotic disease affecting up to 40 kinds of animals and 250 million people. It has been reported that the miRNAs play a role in the metabolism, differentiation, development and reproduction in many organisms. However, the roles of miRNAs regulating the development, maturation and production in schistosome in both females and males remains unclear. Here we present the dynamic transcriptome analysis of all 79 known Schistosoma japonicum miRNAs from pairing to production, including 14 days post-infection (dpi), 16, 18, 20, 22, 24, 26, 28 dpi female and male, by small RNA sequencing. The miRNA expression profiles showed time-related characteristics in male and female from paring to production, which could be clustered into three patterns, characterized by pairing stage highly expressed (cluster 1), maturating stage highly expressed (cluster 2), and egg producing stage highly expressed (cluster 3). The enrichment of miRNA cluster targeted genes in female and male were distinctly different. Network analysis of miRNAs and their target regulation showed that cluster 1 had 15 miRNAs involved in the regulation of interaction, communication, immune response in female-male and parasite-host. The other 11 miRNAs were involved in gender differentiation and the meiotic cell cycle process. In cluster 2, 11 miRNAs were involved in development and sexual maturation. In cluster 3, 45 miRNAs possibly regulate metabolism and synthesis of the substance for egg production. Analysis of the miRNA regulation network would contribute to understanding the molecular mechanism in S. japonicum development and egg production.

Immunomodulatory effects of Trichinella spiralis excretory-secretory antigens on macrophages.

Helminths and their products can suppress the host immune response and other immunopathologies which may benefit parasite survival. Parasitic nematode Trichinella spiralis (T. spiralis) exert immunomodulatory effect on the host immune response through excretory-secretory (ES) products. However, the immunomodulatory mechanism is not yet completely understood or defined. Macrophages play a key role in modulating the host immune response to helminth parasite infection. Here, we focus on the effect of T. spiralis ES antigens on the immune response by studying the effect of ES antigens on RAW264.7 macrophages in vitro. RAW264.7 macrophages were incubated with ES antigens either alone or in combination with LPS. The cytokine production (TNF-α, IL-10 and IL-12 p70) and the expression of TLR were measured. Moreover, the nuclear translocation of MyD88 and NF-кB was assessed by Western blot analysis. Results indicate that ES products had impacts on reducing the expression of TLRs in LPS-induced macrophages. In addition, ES products inhibited the cytokine production of IL-12 p70 and TNF-α and alone boosted the expression of cytokine IL-10 in RAW264.7 macrophages. In conclusion, our results implied that T. spiralis ES antigens may regulate host immune response at the macrophages level in vitro.

The moving junction protein RON4, although not critical, facilitates host cell invasion and stabilizes MJ members.

Toxoplasma gondii is an obligate intracellular parasite of phylum Apicomplexa. To facilitate high-efficiency invasion of host cells, T. gondii secretes various proteins related to the moving junction (MJ) complex from rhoptries and micronemes into the interface between the parasite and host. AMA1/RON2/4/5/8 is an important MJ complex, but its mechanism of assembly remains unclear. In this study, we used the CRISPR-Cas9 system to generate a derivative of T. gondii strain RH with a null mutation in TgRON4, thought to be an essential MJ component. Deficiency of TgRON4 moderately decreased invasion ability relative to that of the wild-type parasite. In addition, expression of the endogenous N-terminal fragment of RON5 decreased in the mutant. Together, the results improve our understanding of the assembly mechanism of the MJ complex of T. gondii and raise the possibility of developing new therapeutic drugs that target this complex.

Molecular characterization of Enterocytozoon bieneusi isolates in laboratory macaques in north China: zoonotic concerns.

The significance of wild and zoo nonhuman primates (NHPs) as potential sources of human Enterocytozoon bieneusi infections has been increasingly appreciated, while the role of laboratory NHPs in zoonotic transmission of microsporidiosis remains elusive. In this study, the infection rate, genetic characteristic, and zoonotic potential of E. bieneusi were investigated for 205 laboratory macaques in Beijing, north China. The parasite was identified in 37 (18.0%) animals by nested PCR and sequencing of the ribosomal internal transcribed spacer (ITS), with an infection rate of 25.6% in Macaca fascicularis (34/133) and 4.2% in Macaca mulatta (3/72). The differences in infection rate between the two species of macaques and between young macaques aged ≤ 5 years (29.6%, 32/108) and adults aged > 5 years (5.2%, 5/97) were significant (p < 0.01). Analysis of the ITS sequence polymorphisms recognized eight known genotypes (CC4, CM1, CM2, D, Peru8, Peru11, Type IV, and WL21) and two new genotypes (named as CMB1 and CMB2), with well-known human-pathogenic genotypes (D, Peru8, Peru11, and Type IV) most frequently detected. The rest genotypes (CC4, CM1, CM2, WL21, CMB1, and CMB2) were clustered into zoonotic group 1 in phylogenetic analysis. The high diversity and widespread presence of the human-pathogenic or group 1 E. bieneusi genotypes in laboratory NHPs, notably M. fascicularis and the young animals, suggest potential of zoonotic transmission. These findings imply that laboratory rhesus macaques could be significant reservoirs for human microsporidiosis.

Functional characterization of X-prolyl aminopeptidase from Toxoplasma gondii.

In the present study, a recombinant aminopeptidase P (rTgAPP) from Toxoplasma gondii was expressed in Escherichia coli to evaluate its enzyme parameters. The rTgAPP showed strong activity against a synthetic substrate for aminopeptidase P at pH 8·0 with a K m value of 0·255 µ m and a k cat value of 35·6 s-1. The overall catalytic efficiency (k cat/K m) of the rTgAPP was 139·6 × 105 M-1 s-1. The activity of rTgAPP was enhanced by the addition of divalent cations and inhibited by bestatin. Deletion of TgAPP gene in the parasite through a CRISPR/Cas9 system resulted in inhibition of growth indicating the importance of TgAPP. Thus our findings reveal that TgAPP is an active enzyme in T. gondii and provide an insight into the function of TgAPP.

Enterocytozoon bieneusi genotypes in children in Northeast China and assessment of risk of zoonotic transmission.

The prevalence (7.5%, 19/255) and genotypes of Enterocytozoon bieneusi in children of various age categories and clinical presentations were determined herein. The co-occurrence of the known genotypes (CS-4, EbpC, and Henan-IV) in children and pigs in the same study area, the phylogenetic characterization of novel genotypes (NEC1 to NEC5), and the assessment of potential risk factors associated with zoonotic transmission robustly suggested that pigs could be a significant source of human E. bieneusi infections in northeast China.

High diversity of human-pathogenic Enterocytozoon bieneusi genotypes in swine in northeast China.

Despite the advances in defining Enterocytozoon bieneusi genotypes worldwide, rare genotypic surveys have been documented on this ubiquitous pathogenic protozoan in mammals in China, especially the role of pigs in zoonotic transmission of microsporidiosis remains unclear. In this study, the distribution of E. bieneusi genotypes in 113 duodenal mucosal specimens of pigs with acute diarrhea from 15 cities in northeast China was determined by PCR and DNA sequence analysis of the ribosomal internal transcribed spacer. The organism was detected in 51 (45.1%) pigs from 12 cities, with infection rates of the nursery pigs (21/33, 63.6%) significantly higher than the preweaned (25/61, 41.0%; P < 0.05) and the growing (5/19, 26.3%; P < 0.01) ones. E. bieneusi belongs to nine known human-pathogenic genotypes (D, EbpA, EbpC, EbpD, H, Henan-I, Henan-III, Henan-IV, and O) and eight new genotypes (CS-1 to CS-8). Genotypes D, EbpA, EbpC, EbpD, Henan-I, Henan-III, and Henan-IV have been found in human infections and D, EbpA, EbpC, and EbpD in wastewater in central China. The new genotypes were genetically clustered into a group of existing E. bieneusi genotypes with zoonotic potential. Considering the discovery of a high prevalence and wide genetic diversity of E. bieneusi zoonotic strains in pigs in northeast China and the co-occurrence of seven known genotypes in pigs and humans and four in pigs and wastewater, pigs probably served as a reservoir for human microsporidiosis and an important source of water contamination in China.

Curcumin improves the egg quality, antioxidant activity, and intestinal microbiota of quails during the late laying period.

This study aimed to investigate the effects of dietary curcumin supplementation on laying performance, egg quality, egg metabolites, lipid metabolism, antioxidant activity, and intestinal microbial composition of quails in the late laying period. A total of 960 late-laying quails (240-day-old) were randomly divided into 4 groups of 6 replicates each (n = 40/replicate). The experimental diets of the 4 groups consisted of basal diets supplemented with 0, 50, 100, and 200 mg/kg curcumin, respectively. The feeding experiment lasted for 8 wk. The results showed that 200 mg/kg curcumin supplementation decreased mortality and increased eggshell thickness and strength compared with the 0 mg/kg curcumin supplementation during wk 5 to 8. In addition, dietary supplementation of curcumin promoted lipid metabolism, enhanced antioxidant activity, and modified intestinal microbiota structure. In conclusion, dietary supplemented with 200 mg/kg curcumin significantly improved the egg quality of quails in the late laying period, primarily by improving lipid metabolism and selectively regulating the intestinal microbial community.

Molecular characterization of Giardia duodenalis isolates from police and farm dogs in China.

To assess the potential zoonotic transmission of giardiasis from dogs in China, a total of 205 fecal specimens from dogs were screened for Giardia duodenalis using PCR and sequence analysis of the triosephosphate isomerase gene. The prevalence of G. duodenalis in dogs was 13.2% (27/205). The potentially zoonotic assemblage A and the dog-specific assemblage C was identified in 25 (12.2%) and two (1.0%) dogs, respectively. All assemblage A isolates belonged to sub-assemblage AI, genotype AI-1. Likewise, one subtype was found in assemblage C. The high occurrence of potentially zoonotic G. duodenalis subtype AI-1 in dogs that are in close contact with humans is of public health concern.

A lightweight attention deep learning method for human-vehicle recognition based on wireless sensing technology.

Wireless sensing-based human-vehicle recognition (WiHVR) methods have become a hot spot for research due to its non-invasiveness and cost-effective advantages. However, existing WiHVR methods shows limited performance and slow execution time on human-vehicle classification task. To address this issue, a lightweight wireless sensing attention-based deep learning model (LW-WADL) is proposed, which consists of a CBAM module and several depthwise separable convolution blocks in series. LW-WADL takes raw channel state information (CSI) as input, and extracts the advanced features of CSI by jointly using depthwise separable convolution and convolutional block attention mechanism (CBAM). Experimental results show that the proposed model achieves 96.26% accuracy on the constructed CSI-based dataset, and the model size is only 5.89% of the state of the art (SOTA) model. The results demonstrate that the proposed model achieves better performance on WiHVR tasks while reducing the model size compared to SOTA model.

Multivalent Effect of Defect Engineered Ag2S/g-C3N4 3D Porous Floating Catalyst with Enhanced Contaminant Removal Efficiency.

Chlorophenols, as a major environmental pollutant, enter water systems through industrial wastewater, agricultural runoff and chemical spills, and they are stable, persistent under natural conditions, and highly hazardous to water resources. The objective of this article is to prepare Ag2S-modified C3N4 three-dimensional network photocatalyst by calcination method to use photocatalysis as an efficient, safe, and environmentally friendly method to degrade chlorophenols. Ag2S/C3N4 has an excellent visible light absorption range, low band gap, effective separation of photogenerated charges, and active free radicals production, all of which make for the enhancement of photocatalytic degradation performance of the Ag2S/C3N4 system. Under the light irradiation (λ ≥ 420 nm), the photocatalytic degradation efficiency of 2,4,6-Trichlorophenol reach 95% within 150 min, and the stable photocatalytic degradation activity can still be maintained under different pH water environment and four degradation cycles. When Ag2S is loaded on ACNs, more photogenerated electrons are generated and subsequent reactions produce highly reactive groups such as •O2- and •OH that will originally be able to continuously attack TCP molecules to degrade pollutants. Therefore, this study shows that the photocatalyst provides a novel research approach for realizing the application in the field of pollutant degradation.