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Summary: Many positive-strand RNA viruses, including all known coronaviruses, employ programmed −1 ribosomal frameshifting (−1 PRF) to regulate the translation of polycistronic viral RNAs. However, only a few host factors have been shown to regulate −1 PRF. Through a genome-wide CRISPR-Cas9 knockout screen, we have identified host factors that either suppress or enhance severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) –1 PRF. Among them, eukaryotic translation initiation factor 2A (eIF2A) specifically and directly enhances −1 PRF independent of changes in initiation. Consistent with the crucial role of efficient −1 PRF in transcriptase/replicase expression, loss of eIF2A reduces SARS-CoV-2 replication in cells. Furthermore, transcriptome-wide analysis shows that eIF2A preferentially binds CG-rich RNA motifs, including a region within 18S ribosomal RNA near the contacts between the SARS-CoV-2 frameshift-stimulatory element (FSE) and the ribosome. Thus, our results indicate a role for eIF2A in modulating the translation of specific RNAs independent of its role during initiation.

Objective To explore whether the abnormality of ambulatory electroencephalogram (AEEG) prior to postoperative drug withdrawal is related to the recurrence of epilepsy after drug discontinuation in patients with glioma related epilepsy (GRE). Methods The clinical data and AEEG of 68 GRE patients who underwent surgical treatment in our hospital with long-term follow-up from January 2014 to June 2020 were collected and retrospectively analyzed. The patients were subsequently divided into seizure group (seizure recurrence after withdrawal of antiepileptic drugs, n=31) and control group (no seizure after withdrawal, n=37). The differences in the occurrence rate and number of spike waves and paroxysmal slow wave events (PSWEs) were analyzed and compared between the 2 groups. The factors affecting the prognosis of epilepsy were discussed through analyzing the data of 47 patients who presented epileptic discharge on AEEG before drug discontinuation. Results ① In the seizure group, 29 patients (93.5%) had epileptic discharges on AEEG before drug withdrawal and 11 (35.5%) showed PSWEs, while there were only 18 (48.6%) and 5 (13.5%) patients correspondingly in the control group, indicating a significant difference in the occurrence rate between the 2 groups (P < 0.05). ② The number of spike and slow waves was significantly larger in the seizure group than the control group. In the seizure group, medium to large number of spike waves (25/29, 86.2%) as well as large number of paroxysmal slow waves (8/11, 72.7%) were predominant, whereas the control group mainly had small amount of spike waves (14/18, 77.8%) and small to medium amount of paroxysmal slow waves (4/5, 80.0%). ③ With epileptic discharge of AEEG, the extent of tumor removal and involvement of cortex were related to the epilepsy prognosis (P < 0.05). Conclusion When the tumor is sub-radical resected or the tumor involves the cortex, and the pre-discontinuation AEEG shows moderate to large number of epileptic discharge and PSWEs, it is necessary to consider suspending drug withdrawal and extending the interval between seizures to reduce the risk of seizure recurrence.

Immunotoxicity evaluation has been crucial in preclinical testing for implantable animal-derived biomaterials due to their prolonged contact with the human body, which requires stringent safety assessments. By creating experimental models with varying levels of immunotoxicity, this study reveals the decisive role of decellularization treatment in diminishing the immunogenicity of materials, thus ensuring clinical safety. Employing cutting-edge differential gene expression analysis, the research not only accurately quantifies gene expression alterations in immune responses but also, through pathway enrichment analysis, identifies gene networks associated with oncogenesis. This offers novel insights into the mechanisms of immune responses following biomaterial implantation. Additionally, the study highlights the importance of developing highly sensitive immunotoxicity testing methods and validates the efficacy of high-throughput sequencing and bioinformatics tools in assessing biomaterial safety, providing robust scientific support for future preclinical evaluations. [ABSTRACT FROM AUTHOR]

Urban forests by the riverside are important habitats for various animals and contribute various soundscapes for citizens. Unfortunately, urban forests are exposed to the influence of riverside traffic noises from freeways. This study aims to explore the spatial and temporal variation of soundscape, conduct soundscape optimization for multiple parameters, and find a balance and its interval of soundscape elements through optimizing a soundscape map. Questionnaires and measuring equipment were used to gather soundscape information in an urban forested area in Fuzhou, China. Diurnal variations and soundscape mapping were used to analyze spatial and psychophysical relationships between soundscape drivers. We then conducted optimization for a soundscape map, which included normalization, critical value determination, target interval of optimal SPL determination, and modification of SPL and mapping. Our findings suggest that biological activities and natural phenomena are potential drivers for diurnal variation of soundscapes, especially tidal phenomena contributing water and shipping soundscapes. Our results also suggest that all the high values of perceived soundscapes were found at the southwest corner of the study area, which includes both riverside and urban forest elements. Furthermore, we suggest combining both optimal soundscape and SPL correction maps to aid in sustainable design in urban forests. This can contribute to the understanding and methodology of soundscape map optimization in urban forests when proposing suitable design plans and conservation of territorial sound.

Objective To investigate the value of high-gamma oscillations (65~100 Hz) in epileptogenic foci localization by analyzing the intraoperative electrocorticography (ECoG) in patients with refractory temporal lobe epilepsy, along with comparing the occurrence rate and distribution characteristics of high-gamma activity as well as spike wave inside and outside the irritative zone and around the foci. Methods A retrospective analysis was carried out on the intraoperative ECoG data of 21 patients with refractory temporal lobe epilepsy in our hospital from January 2013 to January 2019. The channels with interictal epileptiform discharges (IEDs) were defined as irritated area, and those without IEDs as non-irritated area. Based on the preoperative imaging data, intraoperative navigation combined with neurosurgeon's judgment, the monitoring cortical area was divided into focal area, perifocal area and the area away from the focus. Then the occurrence rate and distribution characteristics of IEDs (filter range: 1~30 Hz) and high-gamma were compared, and the distribution of high-gamma activity inside and outside the irritated area, and the incidence of high-gamma around the foci were analyzed. Results ① The overall incidence of IEDs and of high-gamma in the 21 patients were both 100.0% (21/21), and the average number of channels for IEDs, high-gamma and gamma+IEDs was 9.50±2.80, 8.14±2.93 and 6.60±2.40, respectively, indicating notably more IEDs channels than the other 2, by RM one-way ANOVA (P < 0.05). ②The channel numbers of high-gamma were 6.60±2.40 and 1.50±1.30 in the irritated and non-irritated areas respectively, and the event rates were 0.42±0.30 and 0.20±0.20 respectively, showing significant difference between the 2 areas (P < 0.01). ③The event numbers of high-gamma activity were 46.00±42.00, 33.40±32.90 and 8.40±9.40 in the focal area, the perifocal area and the area away from the focus, respectively, with the corresponding event rate of 0.40±0.30, 0.37±0.38 and 0.10±0.10, respectively. There were no significant differences in the event numbers and rates between the focal and perifocal area, though they were both significantly higher than that of the area away from the focus, by paired t-test (P < 0.05). Conclusion Traditional IEDs of ECoG are still an important marker to guide the range of resection intra-operatively in epilepsy surgery, while high-gamma presents great consistency with both IEDs and foci, with more accurate identification of epileptogenic zone than IEDs. Therefore, IEDs combined with high-gamma may have greater value in the localization of epileptogenic zone.

石墨烯具有优异的物理特性,如单原子厚度, 极高的载流子迁移率等。然而,其零带隙的半金 属特性限制了题在高性能场效应晶体管中的应用。为此,研究者们提出了石墨烯纳米化, 外场诱导, 掺杂以及化学图案化等策略,以调控其带隙宽度。但是,这些方法的可控性以及稳定性还需要进一 步改善。在本研究中,我们提出采用电化学溴化并结合光刻图案化调控单层石墨烯的电子传输特性, 通过这种方法,成功制备了图案化的溴化石墨烯(SLGBr)。进一步研究表明,单层石墨烯的电子传 输性能可以通过溴化程度来调控。当溴化程度较小时,SLGBr表现为电阻特性,且其电导随溴化程 度增加而减小;当溴化程度增加到一定值时,SLGBr表现为与半导体类似的特性。本研究将为全石 墨烯器件的制备提供可行的技术路线,拓展其在微电子领域的应用。 [ABSTRACT FROM AUTHOR]

The preparation of active packaging loaded with antimicrobial, antioxidant, and other functional agents has become a hot topic for food preservation in recent years. In this field, active fiber films based on spinning methods have attracted the interest of researchers owing to their high specific surface area, high porosity, high loading capacity, and good controlled release capacity. In the present work, neatly arranged ethyl cellulose (EC)/polyvinyl-pyrrolidone (PVP) fibrous films loaded with natamycin as an antimicrobial agent were prepared by microfluidic spinning. The encapsulation efficiency of natamycin was more than 90% in each group and the loading increased with increasing natamycin content. According to the characterization results of the natamycin-loaded EC/PVP fibrous films, hydrogen bonding was formed between natamycin and EC and PVP in the fibrous films. Meanwhile, the water contact angle of the fibrous films was increased, suggesting the improved hydrophobicity of the films. In the in vitro bacterial inhibition experiments, the active fiber films loaded with natamycin showed good antimicrobial activity, which could significantly inhibit the growth of gray mold. In conclusion, N-EC/PVP fibrous films with antimicrobial activity prepared by microfluidic spinning showed good potential in the field of active packaging. [ABSTRACT FROM AUTHOR]

Taking Chinese fir wood from plantation as the research object, three technological parameters including hot-pressing temperature (160, 180, 200 °C), hot-pressing time (20, 30, 40 min) and compression ratio (30%, 40%, 50%) were selected, and the compression densification modification test of Chinese fir was carried out by using the full factor experimental design. Based on the mechanical properties, microscopic morphology and crystallinity of wood, the effects of different processing parameters on wood properties were analyzed, and the densification process parameters of Chinese fir wood were optimized. The results showed that the properties of the densified wood prepared by Chinese fir were better under the technological conditions of hot pressing temperature of 180 °C, compression ratio of 50%, and pressing time of 40 min. The flexural strength, flexural modulus of elasticity, tensile strength, and hardness of the densified Chinese fir were 130.4 MPa, 12 338 MPa, 113.1 MPa and 1 631 N respectively, which increased by 112%, 113%, 44%, and 55% compared to the untreated wood. The scanning electron microscope observation showed that almost all the early wood cells were crushed, and there were regular folds along the direction of the wood ray, while some of the late wood cells were crushed, and most of them kept the original cavity structure. The hardness and elastic modulus of the cell wall of the densified wood were 16.7% and 45.7% higher than that of the untreated wood. The crystallinity of wood after compression treatment increased. The crystallinity of cellulose in the untreated wood and compressed Chinese fir was 46% and 53%, respectively. [ABSTRACT FROM AUTHOR]