Showing papers by "Yang Yang published in 2022"

Longitudinal analysis of antibody dynamics in COVID-19 convalescents reveals neutralizing responses up to 16 months after infection

Abstract: Elucidating the dynamics of the neutralizing antibody (nAb) response in coronavirus disease 2019 (COVID-19) convalescents is crucial in controlling the pandemic and informing vaccination strategies. Here we measured nAb titres across 411 sequential plasma samples collected during 1-480 d after illness onset or laboratory confirmation (d.a.o.) from 214 COVID-19 convalescents, covering the clinical spectrum of disease and without additional exposure history after recovery or vaccination against SARS-CoV-2, using authentic SARS-CoV-2 microneutralization (MN) assays. Forty-eight samples were also tested for neutralizing activities against the circulating variants using pseudotyped neutralization assay. Results showed that anti-RBD IgG and MN titres peaked at ~120 d.a.o. and subsequently declined, with significantly reduced nAb responses found in 91.67% of COVID-19 convalescents (≥50% decrease in current MN titres compared with the paired peak MN titres). Despite this decline, majority of the COVID-19 convalescents maintained detectable anti-RBD IgG and MN titres at 400-480 d.a.o., with undetectable neutralizing activity found in 14.41% (16/111) of the mild and 50% (5/10) of the asymptomatic infections at 330-480 d.a.o. Persistent antibody-dependent immunity could provide protection against circulating variants after one year, despite significantly decreased neutralizing activities against Beta, Delta and Mu variants. In conclusion, these data show that despite a marked decline in neutralizing activity over time, nAb responses persist for up to 480 d in most convalescents of symptomatic COVID-19, whereas a high rate of undetectable nAb responses was found in convalescents from asymptomatic infections.

Multicenter, single-arm, phase II trial of camrelizumab and chemotherapy as neoadjuvant treatment for locally advanced esophageal squamous cell carcinoma

Abstract: Background Camrelizumab and chemotherapy demonstrated durable antitumor activity with a manageable safety profile as first-line treatment in patients with advanced esophageal squamous cell carcinoma (ESCC). This study aimed to evaluate the safety and efficacy of camrelizumab plus neoadjuvant chemotherapy, using pathologically complete response (pCR) as primary endpoint, in the treatment for locally advanced ESCC. Methods Patients with locally advanced but resectable thoracic ESCC, staged as T1b-4a, N2-3 (≥3 stations), and M0 or M1 lymph node metastasis (confined to the supraclavicular lymph nodes) were enrolled. Eligible patients received intravenous camrelizumab (200 mg, day 1) plus nab-paclitaxel (100 mg/m2, day 1, 8, 15) and carboplatin (area under curve of 5 mg/mL/min, day 1) of each 21-days cycle, for two cycles before surgery. The primary endpoint is pCR rate in the per-protocol population. Safety was assessed in the modified intention-to-treat population that was treated with at least one dose of camrelizumab. Results From November 20, 2019 to December 22, 2020, 60 patients were enrolled. 55 (91.7%) patients completed the full two-cycle treatment successfully. 51 patients underwent surgery and R0 resection was achieved in 50 (98.0%) patients. pCR (ypT0N0) was identified in 20 (39.2%) patients and 5 (9.8%) patients had complete response of the primary tumor but residual disease in lymph nodes alone (ypT0N+). 58 patients (96.7%) had any-grade treatment-related adverse events (TRAEs), with the most common being leukocytopenia (86.7%). 34 patients (56.7%) had adverse events of grade 3 or worse, and one patient (1.7%) occurred a grade 5 adverse event. There was no in-hospital and postoperative 30-day as well as 90-day mortality. Conclusions The robust antitumor activity of camrelizumab and chemotherapy was confirmed and demonstrated without unexpected safety signals. Our findings established camrelizumab and chemotherapy as a promising neoadjuvant treatment for locally advanced ESCC. Trial registration number ChiCTR1900026240.

Joint Task Offloading and Caching for Massive MIMO-Aided Multi-Tier Computing Networks

Abstract: In this paper, a massive multiple-input multiple-output (MIMO) relay assisted multi-tier computing (MC) system is employed to enhance the task computation. We investigate the joint design of the task scheduling, service caching and power allocation to minimize the total task scheduling delay. To this end, we formulate a robust non-convex optimization problem taking into account the impact of imperfect channel state information (CSI). In particular, multiple task nodes (TNs) offload their computational tasks either to computing and caching nodes (CCN) constituted by nearby massive MIMO-aided relay nodes (MRN) or alternatively to the cloud constituted by nearby fog access nodes (FAN). To address the non-convexity of the optimization problem, an efficient alternating optimization algorithm is developed. First, we solve the non-convex power allocation optimization problem by transforming it into a linear optimization problem for a given task offloading and service caching result. Then, we use the classic Lagrange partial relaxation for relaxing the binary task offloading as well as caching constraints and formulate the dual problem to obtain the task allocation and software caching results. Given both the power allocation, as well as the task offloading and caching result, we propose an iterative optimization algorithm for finding the jointly optimized results. The simulation results demonstrate that the proposed scheme outperforms the benchmark schemes, where the power allocation may be controlled by the asymptotic form of the effective signal-to-interference-plus-noise ratio (SINR).

Artificial Heterogeneous Interphase Layer with Boosted Ion Affinity and Diffusion for Na/K‐Metal Batteries

Abstract: Metallic Na (K) are considered a promising anode materials for Na‐metal and K‐metal batteries because of their high theoretical capacity, low electrode potential, and abundant resources. However, the uncontrolled growth of Na (K) dendrites severely damages the stability of the electrode/electrolyte interface, resulting in battery failure. Herein, a heterogeneous interface layer consisting of metal vanadium nanoparticles and sodium sulfide (potassium sulfide) is introduced on the surface of a Na (K) foil (i.e., Na2S/V/Na or K2S/V/K). Experimental studies and theoretical calculations indicate that a heterogeneous Na2S/V (K2S/V) protective layer can effectively improve Na (K)‐ion adsorption and diffusion kinetics, inhibiting the growth of Na (K) dendrites during Na (K) plating/stripping. Based on the novel design of the heterogeneous layer, the symmetric Na2S/V/Na cell displays a long lifespan of over 1000 h in a carbonate‐based electrolyte, and the K2S/V/K electrode can operate for over 1300 h at 0.5 mA cm–2 with a capacity of 0.5 mAh cm–2. Moreover, the Na full cell (Na3V2(PO4)3||Na2S/V/Na) exhibits a high energy density of 375 Wh kg–1 and a high power density of 23.5 kW kg–1. The achievements support the development of heterogeneous protective layers for other high‐energy‐density metal batteries.

Nitrogen fertilization weakens the linkage between soil carbon and microbial diversity: A global meta‐analysis

Abstract: Soil microbes make up a significant portion of the genetic diversity and play a critical role in belowground carbon (C) cycling in terrestrial ecosystems. Soil microbial diversity and organic C are often tightly coupled in C cycling processes; however, this coupling can be weakened or broken by rapid global change. A global meta‐analysis was performed with 1148 paired comparisons extracted from 229 articles published between January 1998 and December 2021 to determine how nitrogen (N) fertilization affects the relationship between soil C content and microbial diversity in terrestrial ecosystems. We found that N fertilization decreased soil bacterial (−11%) and fungal diversity (−17%), but increased soil organic C (SOC) (+19%), microbial biomass C (MBC) (+17%), and dissolved organic C (DOC) (+25%) across different ecosystems. Organic N (urea) fertilization had a greater effect on SOC, MBC, DOC, and bacterial and fungal diversity than inorganic N fertilization. Most importantly, soil microbial diversity decreased with increasing SOC, MBC, and DOC, and the absolute values of the correlation coefficients decreased with increasing N fertilization rate and duration, suggesting that N fertilization weakened the linkage between soil C and microbial diversity. The weakened linkage might negatively impact essential ecosystem services under high rates of N fertilization; this understanding is important for mitigating the negative impact of global N enrichment on soil C cycling.

Global effects on soil respiration and its temperature sensitivity depend on nitrogen addition rate

Abstract: Soil respiration (Rs) plays a crucial role in regulating carbon (C) cycling in terrestrial ecosystems and the atmospheric carbon dioxide (CO2) concentration. However, the impact of nitrogen (N) addition on Rs and its temperature sensitivity (Q10) is poorly understood. Here, we used 1413 paired observations from 261 studies to explore how N addition affects Rs and its Q10 across terrestrial ecosystems on a global scale. Nitrogen addition increased autotrophic respiration in croplands, deserts and shrublands, but decreased it in grasslands, forests (including coniferous and deciduous forests) and wetlands. In contrast, N addition increased heterotrophic respiration in grasslands, wetlands and deserts, but decreased its Q10 across different ecosystem types other than deserts. Nitrogen addition decreased (p < 0.05) the overall Rs and its Q10 by 19.5 and 32.1%, respectively. The decrease in Rs in response to N addition might be attributed to a reduction in heterotrophic respiration. Moreover, the Rs and its Q10 decreased while soil organic C content increased with the increasing rate of N addition up to 100–150 kg ha−1 yr−1. The results suggest that 100–150 kg N ha−1 yr−1 was the optimum N addition rate to maintain the soil as a C sink. In addition, soil pH, C:N ratio and respiratory quotient were significant predictors of soil respiration and its Q10. Our study highlights that the N addition rate-dependent effects on Rs and its Q10, and soil organic C should be incorporated into global C models to improve the assessment of N addition effects on the global C cycle.

Towards a better understanding of the role of Fe cycling in soil for carbon stabilization and degradation

Abstract: Abstract Iron (Fe) minerals play an important role in stabilizing soil organic carbon (SOC). Fe-mediated SOC protection is mainly achieved through adsorption, co-precipitation, or aggregation. However, newly emerging evidence indicates that the electron transfer role of Fe exerts a crucial influence upon SOC turnover. In this review, we address the pathways of Fe mineral-associated soil organic carbon (Fe-SOC) formation and decomposition, and summarize the Fe-mediated biogeochemical, including redox reactions, and physical processes that control SOC cycling. The reduction of Fe can release SOC from Fe-SOC coprecipitates and Fe(III) cemented micro-aggregates, with the process also releasing CO 2 from the metabolic coupling of SOC oxidation and Fe reduction. The abiotic oxidation of Fe(II) by oxidants can also oxidize SOC to produce CO 2 due to reactive oxygen species production. Therefore, the functional roles of Fe on SOC sequestration may be a double-edged sword, and these processes are rarely explored concurrently. We conclude that the roles of Fe minerals in SOC stability depend on the properties of the Fe mineral, edaphic properties, and anthropogenic influence. We highlight knowledge gaps and promising directions of future research in redox-dynamic environments to optimize carbon storage in soil. Graphical Abstract

Fluorogenic DNA-PAINT for faster, low-background super-resolution imaging

Abstract: DNA-based points accumulation for imaging in nanoscale topography (DNA-PAINT) is a powerful super-resolution microscopy method that can acquire high-fidelity images at nanometer resolution. It suffers, however, from high background and slow imaging speed, both of which can be attributed to the presence of unbound fluorophores in solution. Here we present two-color fluorogenic DNA-PAINT, which uses improved imager probe and docking strand designs to solve these problems. These self-quenching single-stranded DNA probes are conjugated with a fluorophore and quencher at the terminals, which permits an increase in fluorescence by up to 57-fold upon binding and unquenching. In addition, the engineering of base pair mismatches between the fluorogenic imager probes and docking strands allowed us to achieve both high fluorogenicity and the fast binding kinetics required for fast imaging. We demonstrate a 26-fold increase in imaging speed over regular DNA-PAINT and show that our new implementation enables three-dimensional super-resolution DNA-PAINT imaging without optical sectioning. Two-color fluorogenic DNA-PAINT introduces self-quenching, kinetics-optimized probe designs. This approach improves imaging speed 26-fold and eliminates the need for optical sectioning.

In Situ Fabrication of Cs3Cu2I5: Tl Nanocrystal Films for High-Resolution and Ultrastable X-ray Imaging.

Abstract: Cs3Cu2I5 nanocrystals (NCs) are considered to be promising materials due to their high photoluminescence efficiency and X-ray hardness. However, the present strategy depends on tedious fabrication with excessive chemical waste. The evasive iodide ion dissociation, inadaptable ligand system, low stability, and relatively low light yield severely impede their applications. Herein, we develop an in situ fabrication strategy for a flexible and large-area Tl-doped Cs3Cu2I5 NC-polymer composite scintillation film with a high light yield (∼48800 photons/MeV) and improved stability. Tween 80 and phosphinic acid successfully inhibit the oxidation of iodide ions, and the films can be stored for at least six months. As a result, a high spatial resolution of 16.3 lp mm-1 and a low detection limit of 305 nGyair s-1 were achieved. A radioluminescence intensity of >80% was maintained after a total irradiation dose of 604.8 Gy. These results indicate the promising application of these copper halide NCs in low-cost, flexible, and high-performance medical imaging.

Gut Microbiome Alterations in Patients With Visceral Obesity Based on Quantitative Computed Tomography

Abstract: The gut microbiota is crucial in the pathogenesis of obesity. Abdominal obesity is known to significantly increase the risk of metabolic syndrome and cardiovascular disease, so further study is needed to investigate the changes of intestinal microorganisms in patients with excessive visceral fat. In our study, 41 people (n = 41) with normal body mass index (BMI) (18.5 ≤ BMI < 23.9) were included and divided into the low visceral fat area (L-VFA) group (n = 23, VFA < 100 cm2) and the high visceral fat area (H-VFA) group (n = 18, VFA ≥ 100 cm2). Several clinical indicators of the H-VFA group were significantly higher than those of the L-VFA group, including the waist circumference (WC), the fasting blood glucose (FBG), the triglyceride (TG), the total cholesterol (TC), the low-density lipoprotein cholesterol (LDL), the serum uric acid (SUA), the white blood cell count (WBC), the blood neutrophil count (NEC), and the blood lymphocyte count (LYC). Using whole-genome shotgun sequencing, we found that the types of the intestinal microbiota of H-VFA patients were different from those of the L-VFA patients, with 18 bacteria enriched in the H-VFA group and nine bacteria in the L-VFA group. A total of 16 species of gut microbes showed a strong correlation with VFA, and Escherichia coli has the strongest correlation, followed by Mitsuokella unclassified, Bifidobacterium longum, Escherichia unclassified, Ruminococcus torques, Dialister succinatiphilus, Eubacterium hallii, and Ruminococcus gnavus. Compared to the VFA, only two species show a strong correlation with BMI and WC. Further functional genetic studies suggested that the degradation of short-chain fatty acids (SCFAs) and the generation of lipopolysaccharide (LPS) might be related to visceral fat accumulation. Together, visceral fat was more closely correlated with the gut microbiome compared with BMI and WC. It suggested an intrinsic connection between the gut microbiome and visceral fat and its related metabolic disorders. Specific microbial species and pathways associated with visceral fat accumulation might contribute to new targeted therapies for visceral fat and its metabolic disorders.

Bi-Directional Progressive Guidance Network for RGB-D Salient Object Detection

Abstract: Most existing RGB-D salient detection models pay more attention to the quality of the depth images, while in some special cases, the quality of RGB images may even have greater impacts on saliency detection, which has long been ignored and underestimated. To address this problem, in this paper, we present a Bi-directional Progressive Guidance Network (BPGNet) for RGB-D salient object detection, where the qualities of both RGB and depth images are involved. Since it is usually difficult to determine which modality data have low quality in advance, a bi-directional framework based on progressive guidance (PG) strategy is employed to extract and enhance the unimodal features with the aid of another modality data via the alternative interactions between the saliency prediction results and the extracted features from the multi-modality input data. Specifically, the proposed PG strategy is achieved by using the proposed Global Context Awareness (GCA), Auxiliary Feature Extraction (AFE) and Cross-modality Feature Enhancement (CFE) modules. Benefiting from the proposed PG strategy, the disturbing information within the input RGB and depth images can be well suppressed, while the discriminative information within the input images gets enhanced. On top of that, a Fusion Prediction Module (FPM) is further designed to adaptively select those features with higher discriminability as well as enhancing the common information for the final saliency prediction. Experimental results demonstrate that our proposed model is comparable to those of state-of-the-art RGB-D SOD models.

Initial soil formation by biocrusts: Nitrogen demand and clay protection control microbial necromass accrual and recycling

Abstract: Microbial biomass is increasingly considered to be the main source of organic carbon (C) sequestration in soils. Quantitative information on the contribution of microbial necromass to soil organic carbon (SOC) formation and the factors driving necromass accumulation, decomposition and stabilization during the initial soil formation in biological crusts (biocrusts) is absent. To address this knowledge gap, we investigated the composition of microbial necromass and its contributions to SOC sequestration in a biocrust formation sequence consisting of five stages: bare sand, cyanobacteria stage, cyanobacteria-moss stage, moss-cyanobacteria stage, and moss stage on sandy parent material on the Loess Plateau. The fungal and bacterial necromass C content in soil was analyzed based on amino sugars - the cell wall biomarker. Microbial necromass was an important source of SOC, and was incorporated into the particulate and mineral-associated organic C (MAOC). Because bacteria have smaller and thinner cell wall fragments as well as more proteins than fungi, bacterial necromass mainly contributed to the MAOC pool, while fungal residues remained more in the particulate organic C (POC). MAOC pool was saturated fast with the increase of microbial necromass, and POC more rapid accumulation than MAOC suggests that the clay content was the limiting factor for stable C accumulation in this sandy soil. The necromass exceeding the MAOC stabilization level was stored in the labile POC pool (especially necromass from fungi). Activities of four enzymes (i.e., β-1,4-glucosidase, β-1,4-N-acetyl-glucosaminidase, leucine aminopeptidase, and alkaline phosphatase) increasing with fungal and bacterial necromass suggest that the raised activity of living microorganisms accelerated the turnover and formation of necromass. Microbial N limitation raised the production of N acquisition enzymes (e.g., β-1,4-N-acetyl-glucosaminidase and leucine aminopeptidase) to break down necromass compounds, leading to further increase of the nutrient pool in soil solution. The decrease of microbial N limitation along the biocrusts formation chronosequence is an important factor for the necromass accumulation during initial soil development. High microbial N demands and insufficient clay protection lead to fast necromass reutilization by microorganisms and thus, result in a low necromass accumulation coefficient, that is, the ratio of microbial necromass to living microbial biomass (on average, 9.6). Consequently, microbial necromass contribution to SOC during initial soil formation by biocrust is lower (12–25%) than in fully developed soils (33%–60%, literature data). Nitrogen (N) limitation of microorganisms and an increased ratio between N-acquiring enzyme activities and microbial N, as well as limited clay protection, resulted in a low contribution of microbial necromass to SOC by initial formation of biocrust-covered sandy soil. Summarizing, soil development leads not only to SOC accumulation, but also to increased contribution of microbial necromass to SOC, whereas the plant litter contribution decreases. • Microbial necromass C contribution to SOC in biocrust-covered sandy soils was less than 25%. • Biocrust-covered sandy soils have a low necromass accumulation coefficient. • Low soil clay content leads to more microbial necromass forming particulate organic carbon. • Microbial nitrogen limitation was common in biocrust formation sequences. • Microbial N limitation and insufficient clay protection control the necromass dynamics.

Switching the NIR upconversion of nanoparticles for the orthogonal activation of photoacoustic imaging and phototherapy

Abstract: Phototheranostics based on upconversion nanoparticles (UCNPs) offer the integration of imaging diagnostics and phototherapeutics. However, the programmable control of the photoactivation of imaging and therapy with minimum side effects is challenging due to the lack of ideal switchable UCNPs agents. Here we demonstrate a facile strategy to switch the near infrared emission at 800 nm from rationally designed UCNPs by modulating the irradiation laser into pulse output. We further synthesize a theranostic nanoagent by combining with a photosensitizer and a photoabsorbing agent assembled on the UCNPs. The orthogonal activation of in vivo photoacoustic imaging and photodynamic therapy can be achieved by altering the excitation modes from pulse to continuous-wave output upon a single 980 nm laser. No obvious harmful effects during photoexcitation was identified, suggesting their use for long-term imaging-guidance and phototherapy. This work provides an approach to the orthogonal activation of imaging diagnostics and photodynamic therapeutics.

Conductive Covalent Organic Frameworks with Conductivity- and Pre-Reduction-Enhanced Electrochemiluminescence for Ultrasensitive Biosensor Construction.

Abstract: Covalent organic frameworks (COFs) have attracted widespread attention in the electrochemiluminescence (ECL) field owing to their high load capacity of ECL luminophores and porous structures, but their ECL performance is still limited by the intrinsic poor conductivity (generally <10-8 S m-1). To address this shortcoming, we used 2,3,6,7,10,11-hexaaminotriphenylene (HATP) and 2,3,6,7,10,11-hexahydroxytriphenylene (HHTP) to synthesize a conductive COF (HHTP-HATP-COF, conductivity = 3.11 × 10-4 S m-1). Compared with HATP, HHTP, and low-conductive HHTP-DABZ-COF, HHTP-HATP-COF exhibited superior ECL performance, not only because HHTP-HATP-COF possessed massive ECL luminophores but also because its conductive porous framework accelerated charge transport in the whole framework and improved the utilization ratio of ECL luminophores. More interestingly, the ECL intensity of the HHTP-HATP-COF/S2O82- system was further improved after pre-reduction electrolysis due to the accumulation of HHTP-HATP-COF cation radicals. The experimental results showed that the ECL intensity of the HHTP-HATP-COF/S2O82- system after pre-reduction was about 1.64-, 3.96-, 6.88-, and 8.09-fold higher than those of HHTP-HATP-COF/S2O82-, HHTP-DABZ-COF/S2O82-, HHTP/S2O82-, and HATP/S2O82- systems, respectively. Considering the superior ECL property of the HHTP-HATP-COF/S2O82- system after pre-reduction, it was used as a high-efficient ECL beacon together with an aptamer/protein proximity binding-induced three-dimensional bipedal DNA walker to construct an ultrasensitive biosensor for thrombin detection, which displayed broad linearity (100 aM to 1 nM) with a detection limit of 62.1 aM. Overall, the work offered effective ways to increase ECL performance by the enhancement of conductivity and by the pre-reduction, proposing new ideas to design high-efficiency COF-based ECL materials and endowing conductive COFs with ECL biosensor application for the first time.

Optimizing the Interlayer Spacing of Heteroatom-Doped Carbon Nanofibers toward Ultrahigh Potassium-Storage Performances.

Abstract: Precise control over the interlayer spacing for K+ intercalation is an effective approach to boost the potassium-storage performances in carbonaceous materials. Herein, we first found that the optimal interlayer spacing for K+ intercalation is around 0.38 nm for N, O codoped carbon nanofibers (NOCNs), displaying a reversible capacity of 627 mAh g-1 at 0.1 A g-1 after 200 cycles, excellent rate capability (123 mAh g-1 at 20 A g-1), and ultrastable cycling stability (262 mAh g-1 at 5 A g-1 after 10 000 cycles). Such good potassium-storage performances have never been reported in carbonaceous materials. The theoretical calculations and electrochemical studies reveal that the optimal interlayer spacing and N, O heteroatom-induced active sites work together to provide an intercalation-adsorption mechanism for storing K+ in carbonaceous materials. This work facilitates the understanding of the role of the critical interlayer spacing for K+ intercalation in carbonaceous materials.

Breaking scaling relationships in alkynol semi-hydrogenation by manipulating interstitial atoms in Pd with d-electron gain

Abstract: Abstract Pd catalysts are widely used in alkynol semi-hydrogenation. However, due to the existence of scaling relationships of adsorption energies between the key adsorbed species, the increase in conversion is frequently accompanied by side reactions, thereby reducing the selectivity to alkenols. We report that the simultaneous increase in alkenol selectivity and alkynol conversion is achieved by manipulating interstitial atoms including B, P, C, S and N in Pd catalysts. A negative linear relationship is observed between the activation entropies of 2-methyl-3-butyn-2-ol and 2-methyl-3-buten-2-ol which is highly related to the filling of d -orbital of Pd catalysts by the modification of p -block elements. A catalyst co-modified by B and C atoms has the maximum d charge of Pd that achieves a 17-fold increase in the turn-over frequency values compared to the Lindlar catalysts in the semi-hydrogenation of 2-methyl-3-butyn-2-ol. When the conversion is close to 100%, the selectivity can be as high as 95%.

Optimizing the nitrogen configuration in interlayer-expanded carbon materials via sulfur-bridged bonds toward remarkable energy storage performances

Abstract: Carbon materials are promising anodes for potassium ion batteries (PIBs) in terms of its high conductivity, structural stability, and abundant resoures, while its capacity and rate capability are still unsatisfactory...

Breaking scaling relationships in alkynol semi-hydrogenation by manipulating interstitial atoms in Pd with d-electron gain

Abstract: Abstract Pd catalysts are widely used in alkynol semi-hydrogenation. However, due to the existence of scaling relationships of adsorption energies between the key adsorbed species, the increase in conversion is frequently accompanied by side reactions, thereby reducing the selectivity to alkenols. We report that the simultaneous increase in alkenol selectivity and alkynol conversion is achieved by manipulating interstitial atoms including B, P, C, S and N in Pd catalysts. A negative linear relationship is observed between the activation entropies of 2-methyl-3-butyn-2-ol and 2-methyl-3-buten-2-ol which is highly related to the filling of d -orbital of Pd catalysts by the modification of p -block elements. A catalyst co-modified by B and C atoms has the maximum d charge of Pd that achieves a 17-fold increase in the turn-over frequency values compared to the Lindlar catalysts in the semi-hydrogenation of 2-methyl-3-butyn-2-ol. When the conversion is close to 100%, the selectivity can be as high as 95%.

Deciphering factors driving soil microbial life‐history strategies in restored grasslands

Abstract: In macroecology, the concept of r- and K-strategy has been widely applied, yet, there have been limited studies on microbial life-history strategies in temperate grasslands using multiple sequencing approaches. Total phospholipid fatty acid (PLFA) analysis, high-throughput meta-genomic sequencing, and GeoChip technologies were used to examine the changes in microbial life-history traits in a chronosequence of restored grasslands (1, 5, 10, 15, 25, and 30 years since restoration). Grassland restoration increased the relative abundances of Actinobacteria, Proteobacteria, and Bacteroidetes but reduced the relative abundances of Acidobacteria, Planctomycetes, and Chloroflexi. PLFA analysis revealed that grassland restoration reduced the fungi:bacteria and Gram-positive:Gram-negative bacteria ratios. Combined with the meta-genomic data, we found that grassland restoration shifted microorganisms from oligotrophic (K-) to copiotrophic (r-) groups, consistent with the increased rRNA operon copy number of the microbial community. Structural equation modeling showed that soil properties positively (p < 0.05) while plant properties negatively (p < 0.05) affected microbial life-history traits. We built a framework to highlight the importance of plant and soil properties in driving microbial life-history traits during grassland restoration. Finally, by incorporating meta-genomic and other microbiological data, this study showed that microbial life-history traits support the idea that rRNA operon copy number is a trait that reflects resource availability to soil microorganisms.

Synergy of Weakly-Solvated Electrolyte and Optimized Interphase Enables Graphite Anode Charge at Low Temperature.

Abstract: Graphite anode suffers from great capacity loss and even fails to charge ( i.e. Li + -intercalation) under low temperature, mainly arising from the large overpotential including sluggish de-solvation process and insufficient ions movement in the solid electrolyte interphase (SEI). Herein, an electrolyte is developed by utilizing weakly solvated molecule ethyl trifluoroacetate and film-forming fluoroethylene carbonate to achieve smooth de-solvation and high ionic conductivity at low temperature. Evolution of SEI formed at different temperatures is further investigated to propose an effective room-temperature SEI formation strategy for low-temperature operations. The synergetic effect of tamed electrolyte and optimized SEI enables graphite with a reversible charge/discharge capacity of 183 mAh g -1 at -30 o C and fast-charge up to 6C-rate at room temperature. Moreover, graphite||LiFePO 4 full cell maintains a capacity retention of 78% at -30°C, and 37% even at super-low temperature of -60°C. This work offers a progressive insight towards fast-charging and low-temperature batteries.

Coronaviruses Nsp5 Antagonizes Porcine Gasdermin D-Mediated Pyroptosis by Cleaving Pore-Forming p30 Fragment

Abstract: Recently, GSDMD has been reported as a key executioner for pyroptosis. This study first demonstrates the molecular mechanism of pGSDMD-mediated pyroptosis and that the pGSDMD-mediated pyroptosis protects host cells against PEDV infection. ABSTRACT Coronaviruses (CoVs) are a family of RNA viruses that typically cause respiratory, enteric, and hepatic diseases in animals and humans. Here, we use porcine epidemic diarrhea virus (PEDV) as a model of CoVs to illustrate the reciprocal regulation between CoV infection and pyroptosis. For the first time, we elucidate the molecular mechanism of porcine gasdermin D (pGSDMD)-mediated pyroptosis and demonstrate that amino acids R238, T239, and F240 within pGSDMD-p30 are critical for pyroptosis. Furthermore, 3C-like protease Nsp5 from SARS-CoV-2, MERS-CoV, PDCoV, and PEDV can cleave pGSDMD at the Q193-G194 junction to produce two fragments unable to trigger pyroptosis. The two cleaved fragments could not inhibit PEDV replication. In addition, Nsp5 from SARS-CoV-2 and MERS-CoV also cleave human GSDMD (hGSDMD). Therefore, we provide clear evidence that PEDV may utilize the Nsp5-GSDMD pathway to inhibit pyroptosis and, thus, facilitate viral replication during the initial period, suggesting an important strategy for the coronaviruses to sustain their infection. IMPORTANCE Recently, GSDMD has been reported as a key executioner for pyroptosis. This study first demonstrates the molecular mechanism of pGSDMD-mediated pyroptosis and that the pGSDMD-mediated pyroptosis protects host cells against PEDV infection. Notably, PEDV employs its Nsp5 to directly cleave pGSDMD in favor of its replication. We found that Nsp5 proteins from other coronaviruses, such as porcine deltacoronavirus, severe acute respiratory syndrome coronavirus 2, and Middle East respiratory syndrome coronavirus, also had the protease activity to cleave human and porcine GSDMD. Thus, we provide clear evidence that the coronaviruses might utilize Nsp5 to inhibit the host pyroptotic cell death and facilitate their replication during the initial period, an important strategy for their sustaining infection. We suppose that GSDMD is an appealing target for the design of anticoronavirus therapies.

6G Network AI Architecture for Everyone-Centric Customized Services

Abstract: Mobile communication standards were developed for enhancing transmission and network performance by using more radio resources and improving spectrum and energy efficiency. How to effectively address diverse user requirements and guarantee everyone's Quality of Experience (QoE) remains an open problem. The Sixth Generation (6G) mobile systems will solve this problem by utilizing heterogenous network resources and pervasive intelligence to support everyone-centric customized services anywhere and anytime. In this article, we first coin the concept of Service Requirement Zone (SRZ) on the user side to characterize and visualize the integrated service requirements and preferences of specific tasks of individual users. On the system side, we further introduce the concept of User Satisfaction Ratio (USR) to evaluate the system's overall service ability of satisfying a variety of tasks with different SRZs. Then, we propose a network Artificial Intelligence (AI) architecture with integrated network resources and pervasive AI capabilities for supporting customized services with guaranteed QoEs. Finally, extensive simulations show that the proposed network AI architecture can consistently offer a higher USR performance than the cloud AI and edge AI architectures with respect to different task scheduling algorithms, random service requirements, and dynamic network conditions.

High sulfur loading and shuttle inhibition of advanced sulfur cathode enabled by graphene network skin and N, P, F-doped mesoporous carbon interfaces for ultra-stable lithium sulfur battery

Abstract: Achieving high loading of active sulfur yet rational regulating the shuttle effect of lithium polysulfide (LiPS) is of great significance in pursuit of high-performance lithium-sulfur (Li-S) battery. Herein, we develop a free-standing graphene-nitrogen (N), phosphorus (P) and fluorine (F) co-doped mesoporous carbon-sulfur (G-NPFMC-S) film, which was used as a binder-free cathode in Li-S battery. The developed mesoporous carbon (MC) achieved a high specific surface area of 921 m²·g^–1 with a uniform pore size distribution of 15 nm. The inserted graphene network inside G-NPFMC-S cathode can effectively improve its electrical conductivity and simultaneously restrict the shuttle of LiPS. A high sulfur loading of 86% was achieved due to the excellent porous structures of graphene-NPFMC (G-NPFMC) composite. When implemented as a freestanding cathode in Li-S battery, this G-NPFMC-S achieved a high specific capacity (1,356 mAh·g^–1), favorable rate capability, and long-term cycling stability up to 500 cycles with a minimum capacity fading rate of 0.025% per cycle, outperforming the corresponding performances of NPFMC-sulfur (NPFMC-S) and MC-sulfur (MC-S). These promising results can be ascribed to the featured structures that formed inside G-NPFMC-S film, as that highly porous NPFMC can provide sufficient storage space for the loading of sulfur, while, the N, P, F-doped carbonic interface and the inserted graphene network help hinder the shuttle of LiPS via chemical adsorption and physical barrier effect. This proposed unique structure can provide a bright prospect in that high mass loading of active sulfur and restriction the shuttle of LiPS can be simultaneously achieved for Li-S battery.