RESUMO
The study of wearable systems based on surface electromyography (sEMG) signals has attracted widespread attention and plays an important role in human-computer interaction, physiological state monitoring, and other fields. Traditional sEMG signal acquisition systems are primarily targeted at body parts that are not in line with daily wearing habits, such as the arms, legs, and face. In addition, some systems rely on wired connections, which impacts their flexibility and user-friendliness. This paper presents a novel wrist-worn system with four sEMG acquisition channels and a high common-mode rejection ratio (CMRR) greater than 120 dB. The circuit has an overall gain of 2492 V/V and a bandwidth of 15~500 Hz. It is fabricated using flexible circuit technologies and is encapsulated in a soft skin-friendly silicone gel. The system acquires sEMG signals at a sampling rate of over 2000 Hz with a 16-bit resolution and transmits data to a smart device via low-power Bluetooth. Muscle fatigue detection and four-class gesture recognition experiments (accuracy greater than 95%) were conducted to validate its practicality. The system has potential applications in natural and intuitive human-computer interaction and physiological state monitoring.
RESUMO
In the present study, a novel lytic Vibrio parahaemolyticus phage, vB_VpaP_DE10, was isolated from sewage samples collected in Guangzhou city, China. Transmission electron microscopy revealed that phage vB_VpaP_DE10 has an icosahedral head (52.4 ± 2.5 nm) and a short non-contracted tail (21.9 ± 1.0 nm). Phage vB_VpaP_DE10 lysed approximately 31% (8/26) of the antibiotic-resistant V. parahaemolyticus strains tested. A one-step growth curve showed that phage vB_VpaP_DE10 has a relatively long latency time of 25 min and a burst size of ~19 PFU per cell. The genome of phage vB_VpaP_DE10 is a 42,871-bp-long dsDNA molecule with a G + C content of 49.19% and is predicted to contain 46 open reading frames, 26 of which are predicted to be related to functions such as phage structure, packaging, host lysis, and DNA metabolism. Sequence comparisons suggested that vB_VpaP_DE10 is a member of the genus Maculvirus within the family Autographiviridae. Morphological and genomic analysis indicated that vB_VpaP_DE10 is a novel V. parahaemolyticus phage.
Assuntos
Bacteriófagos , Vibrio parahaemolyticus , Bacteriófagos/genética , Composição de Bases , Genoma Viral , Genômica , Fases de Leitura Aberta , Vibrio parahaemolyticus/virologiaRESUMO
Selenium (Se) is essential for human health, however, Se is deficient in soil in many places all around the world, resulting in human diseases, such as notorious Keshan disease and Keshin-Beck disease. Therefore, Se biofortification is a popular approach to improve Se uptake and maintain human health. Beneficial microorganisms, including mycorrhizal and root endophytic fungi, dark septate fungi, and plant growth-promoting rhizobacteria (PGPRs), show multiple functions, especially increased plant nutrition uptake, growth and yield, and resistance to abiotic stresses. Such functions can be used for Se biofortification and increased growth and yield under drought and salt stress. The present review summarizes the use of mycorrhizal fungi and PGPRs in Se biofortification, aiming to improving their practical use.
RESUMO
Accumulating evidence has indicated that the multiple drug resistant Vibrio parahaemolyticus may pose a serious threat to public health and economic concerns for humans globally. Here, two lytic bacteriophages, namely vB_VpS_BA3 and vB_VpS_CA8, were isolated from sewage collected in Guangzhou, China. Electron microscopy studies revealed both virions taxonomically belonged to the Siphoviridae family with icosahedral head and a long non-contractile tail. The double-stranded DNA genome of phage BA3 was composed of 58648 bp with a GC content of 46.30% while phage CA8 was 58480 bp with an average GC content of 46.42%. In total, 85 putative open reading frames (ORFs) were predicted in the phage BA3 genome while 84 were predicted in that of CA8. The ORFs were associated with phage structure, packing, host lysis, DNA metabolism, and additional functions. Furthermore, average nucleotide identity analysis, comparative genomic features and phylogenetic analysis revealed that BA3 and CA8 represented different isolates but novel members of the family, Siphoviridae. Regarding the host range of the 61 V. parahaemolyticus isolates, BA3 and CA8 had an infectivity of 8.2 and 36.1%, respectively. Furthermore, â¼100 plaque-forming units (pfu)/cell for phage BA3 and â¼180 pfu/cell for phage CA8 were determined to be the viral load under laboratory growth conditions. Accordingly, the phage-killing assay in vitro revealed that phage CA8 achieved approximately 3.65 log unit reductions. The present results indicate that CA8 is potentially applicable for biological control of multidrug resistant V. parahaemolyticus.