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Panose is iso-malto-oligosaccharide contained α-1,6 glycosidic bonds, and α-glucosidase is the key enzyme to produce panose. In this study, the α-glucosidase gene in deep-sea hydrothermal vents thermophilic archaea Thermococcus siculi HJ21 was synthesized, and cloned into the vector pET29a. Then expressed in Escherichia coli BL21 and purified by His Trap HP column. The molecular weight of α-glucosidase was determined by SDS-PAGE. The enzymatic properties and transglycosylation were also investigated. The results showed that the gene of α-glucosidase was 729 bp and encoded 242 amino acids. The molecular weight of α-glucosidase was about 27.2 kDa. Its optimal temperature and pH were 40 °C and 6.0 respectively. When the receptor was fructose, and the ratio of fructose and maltose was 1:9, the highest yield of panose could reached 79.1% after 10 h reaction. The results provide a basis for producing high-purity panose by α-glucosidase from archaea. [ABSTRACT FROM AUTHOR]

Dextranase (EC 3.2.1.11) is primarily applied in food, sugar, and pharmaceutical industries. This study focuses on using a cold shock Escherichia coli expression system to express marine dextranase SP5-Badex; enzyme activity increased about 2.2-fold compared to previous expression. This enzyme was employed to produce sweet potato porous starch, with special emphasis on the pore size of the starch. The water and oil adsorption rates of the porous starch increased by 1.43 and 1.51 times, respectively. Extensive Fourier transform infrared spectroscopy and X-ray diffraction revealed that the crystal structure of the sweet potato starch was unaltered by enzymatic hydrolysis. The adsorption capacities of the porous starch for curcumin and proanthocyanidins were 9.59 and 12.29 mg/g, respectively. Notably, the stability of proanthocyanidins was significantly enhanced through their encapsulation in porous starch. After 2.5 h of ultraviolet irradiation, the free radical scavenging rate of the encapsulated proanthocyanidins remained at 95.10%. Additionally, after 30 days of sunlight exposure, the free radical scavenging rate of the encapsulated proanthocyanidins (84.42%) was significantly higher than that (24.34%) observed in the control group. These research findings provide substantial experimental evidence for preparing sweet potato porous starch using marine dextranase. [ABSTRACT FROM AUTHOR]

Due to low costs and high light transmittance, solution-processed NiOx nanocrystals as the hole transport layer (HTL) for inverted perovskite solar cells (PSCs) have attracted great attention recently. Nevertheless, the intrinsic defects (Ni vacancies) in the NiOx film and the I vacancies at the buried interface of the perovskite limit the performance of PSCs. Thus, in this work, iodine-substituted phenyl acids are used to modify the NiOx/perovskite layer interface. Our results show that the acid functional groups have strong coordination with Ni vacancies in the NiOx film, giving rise to a high conductivity of NiOx films and thereby an improved hole transport capacity. The para-iodine gives the molecule a larger dipole moment, leading to a better energy level alignment between NiOx and the perovskite and thereby a favorable hole transfer through the NiOx/perovskite interface. As a result, the PSC based on 4-iodophenylboronic acid yields a champion power conversion efficiency (PCE) of 22.91% and an improved fill factor of 86.18%. The non-encapsulated device maintains above 80% of its initial PCE after storing in N2 for 3000 h, under heating at 60 °C for 1000 h and in air with a relative humidity (RH) of 50–70% for 1000 h. [ABSTRACT FROM AUTHOR]

Enrofloxacin (ENR) is widely used as a synthetic fluoroquinolone antibiotic for disease control in aquatic animals. ENR aptamers were screened in this study using the magnetic bead-SELEX method, and a graphene oxide fluorescent sensor was developed to detect the ENR residues in aquatic products. Firstly, ENR was conjugated to amino magnetic beads by amidation reaction, and then the aptamer sequences showing high affinity to ENR were screened step by step by using the SELEX screening method. Finally, after 10 rounds of SELEX screening, six candidate aptamers with high affinity were obtained. Among these, ENR-Apt 6 was selected based on its secondary structure features, high affinity ( K d = 35.08 nM), and high specificity to ENR. Furthermore, a fluorescent sensor was prepared using graphene oxide and ENR-Apt 6. The results showed that the linear range of the sensor could reach 600 nM (R 2 = 0.986), while its optimal linear range was 1-400 nM (R 2 = 0.991), with the lowest detection limit of 14.72 nM. The prepared sensor was successfully used for the detection of ENR in real samples, with a recovery range of 83.676-114.992% and a relative standard deviation < 10% for most of the samples.

Pure-phase α-FAPbI 3 quantum dots (QDs) are the focus of an increasing interest in photovoltaics due to their superior ambient stability, large absorption coefficient, and long charge-carrier lifetime. However, the trap states induced by the ligand-exchange process limit the photovoltaic performances. Here, a simple post treatment using methylamine thiocyanate is developed to reconstruct the FAPbI 3 -QD film surface, in which a MAPbI 3 capping layer with a thickness of 6.2 nm is formed on the film top. This planar perovskite heterojunction leads to a reduced density of trap-states, a decreased band gap, and a facilitated charge carrier transport. As a result, a record high power conversion efficiency (PCE) of 16.23% with negligible hysteresis is achieved for the FAPbI 3 QD solar cell, and it retains over 90% of the initial PCE after being stored in ambient environment for 1000 h., (© 2023 Wiley-VCH GmbH.)

Objective: To explore the effect of main caregiver ability evaluation index system (MCAEIS) in neonatal intensive care unit (NICU) in the treatment of hypoxic-ischemic encephalopathy (HIE)., Methods: One hundred and eight cases of HIE preterm infants treated in NICU of the First Hospital of Hebei Medical University from August 2018 to August 2019 were retrospectively analyzed. The infants were divided into routine nursing control group and MCAEIS group, 54 cases each. The control group recieved NICU routine care, and the MCAEIS group was given care by NICU MCAEIS. The nursing ability of the main caregivers in the two groups was evaluated by self-made caregiver ability self-assessment questionnaire; the neurological function was assessed by neonatal behavioral neurological score (NBNA) at discharge and one month after discharge; the incidence of neurological sequelae mental retardation [development quotient (DQ) < 75], epilepsy, cerebral palsy and so on were observed., Results: There were no significant differences in the scores of nursing knowledge, nursing technology or nursing ability between the two groups at admission, but the above scores were significantly improved in the two groups at discharge, and the scores of nursing knowledge, nursing technology and nursing ability of main caregivers in the MCAEIS group were significantly higher than those in the routine nursing control group (nursing knowledge score: 29.84±3.47 vs. 20.83±3.94,nursing technology: 31.47±4.56 vs. 25.12±4.18,nursing ability: 17.28±2.39 vs.12.83±4.78), with significant differences (all P < 0.05). One month after discharge, the neurological function score in MCAEIS group was significantly higher than that of routine nursing control group (39.67±3.76 vs. 35.87±5.71, P < 0.001). The incidence of neurological sequelae in MCAEIS group was significantly lower than that in the routine nursing control group [1.85% (1/54) vs. 12.96% (7/54), P = 0.031]., Conclusions: NICU MCAEIS could scientifically and systematically evaluate the nursing ability of the main caregivers, improve the nursing ability of children, and provide a reference for clinical nursing, which is worthy of widely application.