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•A simple and efficient process for the synthesis of hydroxyl functionalized propiolate bio-monomers derived from D/L xylose and 2-deoxy-D-ribose, respectively.•Regio- and ...stereoregular poly(vinyl ether ester)s with high molecular weight (up to 20.4 kg mol−1) can be obtained at ambient temperature by hydroxyl-yne click polymerization, catalyzed by commercially available organic amines.•The incorporation of rigid structure and stereochemistry into the polymer chain simultaneously enhanced the thermal stability (Td,5% up to 340 °C) andglass transition temperatures (Tg up to 143 °C).•These sugar-based click polymers can be selectively depolymerized employing 1-butanethiol in the presence of N-heterocyclic carbene as organocatalyst, yielding valuable monosaccharide derivatives in almost quantitative yields.
The development of sustainable routes to degradable and bio-based polymers offers a promising solution to tackle the global plastic waste crisis. Herein, three hydroxyl functionalized propiolate bio-monomers have been selectively synthesized from D/L xylose and 2-deoxy-D-ribose, and polymerized via hydroxyl-yne click polymerization catalyzed by commercially available organic amines. The polymerization smoothly proceeded at room temperature to produce sequence-defined poly(vinyl ether ester)s with high thermal stability and high glass transition temperatures, due to the introduction of the rigid cyclic structure and specific stereo-configuration into the polymer backbone. More importantly, the resultant sugar-based poly(vinyl ether ester)s can be selectively depolymerized employing 1-butanethiol in the presence of N-heterocyclic carbene as organocatalyst, yielding thioacetal-functionalized monosaccharide derivatives in good to excellent yields.
Residual coal pillars play an important role in mining the adjacent coal seam safely, managing the gobs and maintaining the stability of abandoned coal mines. The height to diameter ratio (
H/D
) ...affects the stability of residual coal pillars. In this study, uniaxial compressive tests of coal specimens with five
H/D
(2.0, 1.5, 1.0, 0.8 and 0.6) were performed, and the stress, strain and acoustic emission (AE) were monitored. Results show that the uniaxial compressive strength (UCS) and peak strain increase with
H/D
decreasing. An empirical equation is proposed to calculate the UCS based on the
H/D
. The AE activities during coal failure process can be separated into four periods. The span of quiet period and rapid decline period shorten with
H/D
decreasing. The smaller the
H/D
is, the more complicated the failure characteristics of coal will be. The failure form of coal with
H/D
of 2.0, 1.5, and 1.0 is primarily shear failure, while splitting failure along the axial direction is the mainly mode when
H/D
is 0.8 or 0.6. The initiation, expansion, aggregation and connection of micro-cracks can be reflected by the real-time spatial evolution of AE event points.
Flow-electrode capacitive deionization (FCDI) has been studied for its ability to perform continuous deionization; however, there are no reports on the degradation of the desalting performance of ...FCDI under short-circuited closed cycle operation (SCC) mode. In this study, we observed a gradual decrease in FCDI desalting performance and weight increase of the flow-electrode under SCC mode, which mixes the cathode and anode flow-electrodes. Through an analysis of NaCl and water accumulation rates obtained from the weight variation of the flow-electrode, the gradual decline in the desalting performance was caused by a decrease in the content of activated carbon (AC) with ion adsorption sites in the flow-electrodes. This was driven by water transfer from the feed stream to the flow-electrodes through the ion exchange membrane attributed to hydrated ions and osmosis. We calculated the salt adsorption capacity (SAC) and salt adsorption rate (SAR) based on the variable weight of the flow-electrode. The maximum SAC (mSAC) and average SAR (ASAR) values of the FCDI were higher and lower than those of conventional capacitive deionization systems, respectively. This was likely due to the repetitive use of the flow-electrode and long ion transport pathways in the flow-electrode, respectively.
We report desalting behaviors of FCDI under short-circuited closed cycle operation of the flow-electrode mixing of cathode and anode flow-electrodes. Display omitted
•Flow-electrode capacitive deionization under short-circuited closed cycle operation mode.•Water transfer from feed stream to flow-electrode by hydration and osmosis during deionization.•Reduction of desalting performances by hydration and osmosis.•Calculation of salt adsorption capacity and rate including water weight increased by hydration and osmosis.
Natural inspiration: A concise total synthesis of (±)‐stemoamide was completed in eight steps with a 37 % overall yield. A bioinspired N‐acyliminium ion cyclization and an unprecedented dynamic ...ruthenium‐catalyzed cyclocarbonylation ensured the high efficiency of the synthesis. A novel silver‐mediated cyclization of an allenic alcohol shows potential for the future asymmetric synthesis of the target. TMS=trimethylsilyl.
Tripartite motif-containing protein 5α (TRIM5α) is generally known to block the postentry events of HIV-1. Here, we report an uncharacterized role for TRIM5α in the maintenance of viral latency. ...Knockdown of TRIM5α potentiates the transcription of HIV-1 in multiple latency models, which is reversed by shRNA-resistant TRIM5α. TRIM5α suppresses TNFα-activated HIV-1 LTR-driven as well as NF-κB- and Sp1-driven gene expression, with the RING and B-box 2 domains being the essential determinants. Mechanistically, TRIM5α binds to and enhances the recruitment of histone deacetylase 1 (HDAC1) to NF-κB p50 and Sp1. ChIP‒qPCR analyses further reveal that the association of TRIM5α with HIV-1 LTR induces HDAC1 recruitment and local H3K9 deacetylation. Conserved suppression effects of TRIM5α orthologs from multiple species on both HIV-1 and endo-retroelement HERV-K LTR activities have also been demonstrated. These findings provide new insights into the molecular mechanisms by which proviral latency is initially established and activatable proviruses are resilenced by histone deacetylase recruitment.
The newly emerged severe acute respiratory syndrome (SARS) coronavirus-2 (SARS-CoV-2) can result in dysregulated interferon (IFN) responses that contribute to disease severity. The papain-like ...protease of SARS-CoV-2 (SCoV2-PLpro) has been previously reported to attenuate IFN responses, but the underlying mechanism is not fully understood. In this study, we found that SCoV2-PLpro potently suppressed IFN production and signaling induced by Sendai virus as well as RIG-I-like receptor (RLR) signaling pathway components, including RIG-I, MAVS, TBK1, TRAF3, TRAF6, and IRF3. SCoV2-PLpro exhibited different specificity and efficiency than SARS-CoV PLpro, with the former exerting a greater inhibitory effect on the RIG-I- and TRAF3-mediated IFN response but a weaker effect on the MAVS-mediated IFN response. Furthermore, we showed that SCoV2-PLpro significantly reduced K63-ubiquitination of RIG-I, MAVS, TBK1, TRAF3, TRAF6, and IRF3 and K48-ubiquitination of IκBα, which are known critical for the innate immune signal transduction. The deubiquitinating (DUB) activity of SCoV2-PLpro required a catalytic residue cysteine 111 (C111) but not the UBL domain. Notably, by utilizing the DUB-defective C111 mutant, we demonstrated that SCoV2-PLpro targeted RLR signaling pathway regulators
deubiquitination-dependent and -independent mechanisms, with the inhibitory activities of RIG-I and TBK1 correlating with DUB function, whereas the antagonism effects on MAVS, TRAF3, TRAF6, and IRF3 independent on DUB activity. Overall, our results reveal that SCoV2-PLpro evolves differential IFN antagonism activity from SCoV1-PLpro and it targets multiple key RLR signaling pathway components
various mechanisms, providing insights into SARS-CoV-2 pathogenesis and clues for developing antiviral therapies for COVID-19.
Magnetic resonance imaging (MRI) is the preferred examination approach for patients with suspected cervical spondylotic myelopathy (CSM).
To investigate the predictive value of MRI spinal cord ...swelling on the prognosis of decompression surgery in patients with CSM.
A retrospective analysis of 115 patients with CSM who underwent decompression surgery was performed. According to whether cervical MRI showed spinal cord swelling, they were divided into a spinal cord swelling group and non-swelling group. The Modified Japanese Orthopaedic Association (MJOA) score, MJOA improvement rate and abnormal spinal cord enhancement rate in the two groups were compared before and after surgery. Multiple linear regression was used to analyse the influencing factors of the MJOA improvement rate.
The time from symptom onset to operation (t= 2.400, p= 0.018) and preoperative MJOA score in the spinal cord swelling group were lower than those in the non-swelling group (t= 3.253, p= 0.002). The body mass index (t= 2.895, p= 0.005), anteroposterior diameter of the spinal canal (t= 4.421, p< 0.001), cross-sectional area (t= 3.136, p= 0.002), postoperative improvement rate (t= 4.277, p< 0.001) and proportion of abnormal enhancement of the spinal cord in the swelling group were higher than those in the non-swelling group (χ2= 3.136, p= 0.002). The preoperative MJOA score in the swelling group was lower than that in the non-swelling group (t= 2.583, p= 0.013). A multivariate linear regression model revealed that age and spinal cord swelling were independent predictors of MJOA score improvement, explaining 33.2% of the total variation.
Patients with CSM with spinal cord swelling have less time from symptoms to surgery, and the degree of preoperative neurological deterioration is more obvious. Spinal cord swelling is an independent predictor of surgical prognosis in patients with CSM.
Here, a facile fabrication of graphene‐based humidity sensors is reported for smart device design. Focused sunlight photoreduction of graphene oxide (GO) helps to remove most of the oxygen‐containing ...groups on GO sheets, which not only recovers their conductivity but also leads to the formation of a highly porous nanostructure, enabling the manufacture of versatile humidity‐sensing smart devices, such as moisture controllers, humidity detector robots, and even a novel electronic harmonica, through a very simple technique. As an uncomplicated and chemical‐free method, focused sunlight photoreduction of GO provides an avenue to produce versatile sensing devices for the development of smart devices.
A facile fabrication of nanostructured graphene layers with high permeability as moisture sensor is reported for smart device design. Focused sunlight irradiation can induce drastic photoreduction of graphene oxides, which helps to recover the conductivity and form a highly porous structure, enabling the facile fabrication of various moisture‐discriminable smart devices such as a novel electronic harmonica.
Schwannomas in the middle ear and external auditory canal are exceedingly rare. The facial nerve, chorda tympani nerve, and Jacobson’s nerve have rarely been reported as the origins of primary ...schwannomas in the middle ear cavity. We experienced a case of carotid sympathetic plexus (CSP) schwannoma that arose from the carotid canal and extended into the middle ear and external auditory canal. The tumor presented bone erosion of the carotid canal, and it adhered tightly to the internal carotid artery. This report represents the first documented case of a CSP schwannoma, which involved the middle ear and external auditory canal.
The fall armyworm (FAW), Spodoptera frugiperda, has colonized and caused consistent damage in the Eastern hemisphere. The identification of various FAW strains is essential for developing precise ...prevention and control measures. The triosephosphate isomerase (Tpi) gene is recognized as an effective marker closely linked to FAW subpopulations. However, most current studies primarily focus on the comparison of variations in specific gene sites of this gene. In this study, we conducted full-length sequencing of the Tpi genes from 5 representative FAW groups. Our findings revealed that the Tpi genes varied in length from 1220 to 1420 bp, with the primary variation occurring within 4 introns. Notably, the exon lengths remained consistent, at 747 bp, with 37 observed base variations; however, no amino acid variations were detected. Through sequence alignment, we identified 8 stable variation sites that can be used to distinguish FAW strains in the Eastern hemisphere. Additionally, we performed strain identification on 1569 FAW samples collected from 19 provinces in China between 2020 and 2021. The extensive analysis indicated the absence of the rice strain in the samples. Instead, we only detected the presence of the corn strain and the Zambia strain, with the Zambia strain being distributed in a very low proportion (3.44%). Furthermore, the corn strain could be further categorized into 2 subgroups. This comprehensive study provides a valuable reference for enhancing our understanding of FAW population differentiation and for improving monitoring and early warning efforts.
