MoO2 nanosheets anchored with Co nanoparticles as a bifunctional electrocatalytic platform for overall water splitting

Electrochemical water splitting is one of the potential commercial techniques to produce clean hydrogen energy because of the high efficiency and environmental friendliness. However, development of low-cost bifunctional electrocatalysts that can replace Pt-based catalysts for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is challenging. Herein, Co nanoparticles (NPs) are anchored on MoO₂ nanosheets (Co/MoO₂) by thermal reduction of the CoMoO₄ nanosheet array in Ar/H₂. The uniformly distributed Co NPs improve the electron transfer capability and modulate the surface states of the MoO₂ nanosheets to enhance hydrogen desorption and HER kinetics. Moreover, the Co/MoO₂ composite is beneficial to the interfacial structure and the MoO₂ nanosheets prevent aggregation of Co NPs to improve the intrinsic OER characteristics in the alkaline electrolyte. As a result, the Co/MoO₂ electrocatalyst shows low HER and OER overpotentials of 178 and 318 mV at a current density of 10 mA cm^-2 in 1 M KOH. The electrolytic cell consisting of the bifunctional Co/MoO₂ electrodes shows a small voltage of 1.72 V for a current density of 10 mA cm^-2 in overall water splitting.

Iterative Synthesis of Inulin-Type Fructooligosaccharides Enabled by Stereoselective β-d-Fructofuranosylation

Inulin-type fructooligosaccharides (FOSs) constitute an abundant subgroup of fructans with important biological activities. However, the availability of individual fructooligosaccharides with an accurate structure in high purity and quality remains challenging. We herein report the first iterative synthesis of five inulin-type FOSs with degrees of polymerization ranging from 3 to 7 via highly stereoselective β-(2 → 1)-d-fructofuranosylation on a gram scale. Central to the synthesis is the decisive use of the 1-O-TIPS-6-O-picoloyl-protected fructofuranosyl thioglycoside donor, which assured the excellent β-selective glycosylation by the hydrogen-bond-mediated aglycone delivery (HAD).

Structural network efficiency mediates the association between glymphatic function and cognition in mild VCI: a DTI-ALPS study

Background and objective: Vascular cognitive impairment (VCI) can be caused by multiple types of cerebrovascular pathology and is considered a network disconnection disorder. The heterogeneity hinders research progress in VCI. Glymphatic failure has been considered as a key common pathway to dementia recently. The emergence of a new method, Diffusion Tensor Image Analysis Along the Perivascular Space (DTI-ALPS), makes it possible to investigate the changes of the glymphatic function in humans non-invasively. We aimed to investigate alterations of glymphatic function in VCI and its potential impact on network connectivity. Methods: We recruited 79 patients with mild VCI, including 40 with cerebral small vessel disease cognitive impairment (SVCI) and 39 with post-stroke cognitive impairment (PSCI); and, 77 normal cognitive (NC) subjects were recruited. All subjects received neuropsychological assessments and multimodal magnetic resonance imaging scans. ALPS-index was calculated and structural networks were constructed by deterministic tractography, and then, the topological metrics of these structural connectivity were evaluated. Results: The ALPS-index of VCI patients was significantly lower than that of NC subjects (P < 0.001). Multiple linear regression analysis showed that ALPS-index affects cognitive function independently (β = 0.411, P < 0.001). The results of correlation analysis showed that the ALPS-index was correlated with overall vascular risk factor burden (r = -0.263, P = 0.001) and multiple cerebrovascular pathologies (P < 0.05). In addition, global efficiency (Eg) of network was correlated with ALPS-index in both SVCI (r = 0.348, P = 0.028) and PSCI (r = 0.732, P < 0.001) patients. Finally, the results of mediation analysis showed that Eg partially mediated in the impact of glymphatic dysfunction on cognitive impairment (indirect effect = 7.46, 95% CI 4.08-11.48). Conclusion: In both major subtypes of VCI, the ALPS-index was decreased, indicating impaired glymphatic function in VCI. Glymphatic dysfunction may affect cognitive function in VCI by disrupting network connectivity, and, may be a potential common pathological mechanism of VCI. ALPS-index is expected to become an emerging imaging marker for VCI.

The Complete Mitochondrial Genome of Entemnotrochus rumphii, a Living Fossil for Vetigastropoda (Mollusca: Gastropoda)

Pleurotomarioidea represents a truly isolated and basally diverging lineage in Vetigastropoda (Mollusca: Gastropoda) whose fossil record can date back to the late Cambrian, thus providing rare insights into the evolutionary history of molluscs. Here, we sequenced and assembled the complete mitochondrial genome of one representative species from Pleurotomarioidea-Entemnotrochus rumphii (Schepman, 1879)-of which the mitogenome is 15,795 bp in length, including 13 protein-coding genes, two ribosomal RNA genes, and 22 transfer RNA genes. The nucleotide composition was biased toward AT, and A + T content reached 65.2%. E. rumphii was recovered as sister to all other living vetigastropods according to mitogenome-based phylogenetic analysis. The mitochondrial gene order was consistent with major vetigastropods and the hypothetical ancestral gastropoda, suggesting the deep conservation of mitogenome arrangement in Vetigastropoda.

Tunability of space-time wave packet carrying tunable and dynamically changing OAM value

Space-time (ST) wave packets have gained much interest due to their dynamic optical properties. Such wave packets can be generated by synthesizing frequency comb lines, each having multiple complex-weighted spatial modes, to carry dynamically changing orbital angular momentum (OAM) values. Here, we investigate the tunability of such ST wave packets by varying the number of frequency comb lines and the combinations of spatial modes on each frequency. We experimentally generate and measure the wave packets with tunable OAM values from +1 to +6 or from +1 to +4 during a ∼5.2-ps period. We also investigate, in simulation, the temporal pulse width of the ST wave packet and the nonlinear variation of the OAM values. The simulation results show that: (i) a pulse width can be narrower for the ST wave packet carrying dynamically changing OAM values using more frequency lines; and (ii) the nonlinearly varying OAM value can result in different frequency chirps along the azimuthal direction at different time instants.

Ultra-compact x-ray spectrometer for high-repetition-rate laser-plasma experiments

We present in this work the development of an ultra-compact, multi-channel x-ray spectrometer (UCXS). This diagnostic has been specially built and adapted to perform at high-repetition-rate (>1 Hz) for high-intensity, short-pulse laser plasma experiments. X-ray filters of varying materials and thicknesses are chosen to provide spectral resolution up to ΔE ≈ 1 keV over the x-ray energy range of 1-30 keV. These filters are distributed over a total of 25 channels, where each x-ray filter is coupled to a single scintillator. The UCXS is designed to detect and resolve a large variety of laser-driven x-ray sources such as low energy bremsstrahlung emission, fluorescence, and betatron radiation (up to 30 keV). Preliminary results from commissioning experiments at the ABL laser facility at Colorado State University are provided.

Turbulence-resilient pilot-assisted self-coherent free-space optical communications using a photodetector array for bandwidth enhancement

We experimentally demonstrate a 4-Gbit/s 16-QAM pilot-assisted, self-coherent, and turbulence-resilient free-space optical link using a photodetector (PD) array. The turbulence resilience is enabled by the efficient optoelectronic mixing of the data and pilot beams in a free-space-coupled receiver, which can automatically compensate for turbulence-induced modal coupling to recover the data's amplitude and phase. For this approach, a sufficient PD area might be needed to collect the beams while the bandwidth of a single larger PD could be limited. In this work, we use an array of smaller PDs instead of a single larger PD to overcome the beam collection and bandwidth response trade-off. In the PD-array-based receiver, the data and pilot beams are efficiently mixed in the aggregated PD area formed by four PDs, and the four mixing outputs are electrically combined for data recovery. The results show that: (i) either with or without turbulence effects (D/r₀ = ∼8.4), the 1-Gbaud 16-QAM signal recovered by the PD array has a lower error vector magnitude than that of a single larger PD; (ii) for 100 turbulence realizations, the pilot-assisted PD-array receiver recovers 1-Gbaud 16-QAM data with a bit-error rate below 7% of the forward error correction limit; and (iii) for 1000 turbulence realizations, the average electrical mixing power loss of a single smaller PD, a single larger PD, and a PD array is ∼5.5 dB, ∼1.2 dB, and ∼1.6 dB, respectively.

Human infection of avian influenza A H3N8 virus and the viral origins: a descriptive study

BACKGROUND

The H3N8 avian influenza virus (AIV) has been circulating in wild birds, with occasional interspecies transmission to mammals. The first human infection of H3N8 subtype occurred in Henan Province, China, in April, 2022. We aimed to investigate clinical, epidemiological, and virological data related to a second case identified soon afterwards in Hunan Province, China.

METHODS

We analysed clinical, epidemiological, and virological data for a 5-year-old boy diagnosed with H3N8 AIV infection in May, 2022, during influenza-like illness surveillance in Changsha City, Hunan Province, China. H3N8 virus strains from chicken flocks from January, 2021, to April, 2022, were retrospectively investigated in China. The genomes of the viruses were sequenced for phylogenetic analysis of all the eight gene segments. We evaluated the receptor-binding properties of the H3N8 viruses by using a solid-phase binding assay. We used sequence alignment and homology-modelling methods to study the effect of specific mutations on the human receptor-binding properties. We also conducted serological surveillance to detect the H3N8 infections among poultry workers in the two provinces with H3N8 cases.

FINDINGS

The clinical symptoms of the patient were mild, including fever, sore throat, chills, and a runny nose. The patient's fever subsided on the same day of hospitalisation, and these symptoms disappeared 7 days later, presenting mild influenza symptoms, with no pneumonia. An H3N8 virus was isolated from the patient's throat swab specimen. The novel H3N8 virus causing human infection was first detected in a chicken farm in Guangdong Province in December, 2021, and subsequently emerged in several provinces. Sequence analyses revealed the novel H3N8 AIVs originated from multiple reassortment events. The haemagglutinin gene could have originated from H3Ny AIVs of duck origin. The neuraminidase gene belongs to North American lineage, and might have originated in Alaska (USA) and been transferred by migratory birds along the east Asian flyway. The six internal genes had originated from G57 genotype H9N2 AIVs that were endemic in chicken flocks. Reassortment events might have occurred in domestic ducks or chickens in the Pearl River Delta area in southern China. The novel H3N8 viruses possess the ability to bind to both avian-type and human-type sialic acid receptors, which pose a threat to human health. No poultry worker in our study was positive for antibodies against the H3N8 virus.

INTERPRETATION

The novel H3N8 virus that caused human infection had originated from chickens, a typical spillover. The virus is a triple reassortment strain with the Eurasian avian H3 gene, North American avian N8 gene, and dynamic internal genes of the H9N2 viruses. The virus already possesses binding ability to human-type receptors, though the risk of the H3N8 virus infection in humans was low, and the cases are rare and sporadic at present. Considering the pandemic potential, comprehensive surveillance of the H3N8 virus in poultry flocks and the environment is imperative, and poultry-to-human transmission should be closely monitored.

FUNDING

National Natural Science Foundation of China, National Key Research and Development Program of China, Strategic Priority Research Program of the Chinese Academy of Sciences, Hunan Provincial Innovative Construction Special Fund: Emergency response to COVID-19 outbreak, Scientific Research Fund of Hunan Provincial Health Department, and the Hunan Provincial Health Commission Foundation.

A Novel Multivariate Cutting Force-Based Tool Wear Monitoring Method Using One-Dimensional Convolutional Neural Network

Tool wear condition monitoring during the machining process is one of the most important considerations in precision manufacturing. Cutting force is one of the signals that has been widely used for tool wear condition monitoring, which contains the dynamical information of tool wear conditions. This paper proposes a novel multivariate cutting force-based tool wear monitoring method using one-dimensional convolutional neural network (1D CNN). Firstly, multivariate variational mode decomposition (MVMD) is used to process the multivariate cutting force signals. The multivariate band-limited intrinsic mode functions (BLIMFs) are obtained, which contain a large number of nonlinear and nonstationary tool wear characteristics. Afterwards, the proposed modified multiscale permutation entropy (MMPE) is used to measure the complexity of multivariate BLIMFs. The entropy values on multiple scales are calculated as condition indicators in tool wear condition monitoring. Finally, the one-dimensional feature vectors are constructed and employed as the input of 1D CNN to achieve accurate and stable tool wear condition monitoring. The results of the research in this paper demonstrate that the proposed approach has broad prospects in tool wear condition monitoring.

Microstructure Reconstruction and Multiphysics Dynamic Distribution Simulation of the Catalyst Layer in PEMFC

Due to the complexity of both material composition and the structure of the catalyst layer (CL) used in the proton-exchange membrane fuel cell (PEMFC), conjugated heat and mass transfer as well as electrochemical processes simultaneously occur through the CL. In this study, a microstructure model of CL was first reconstructed using images acquired by Nano-computed tomography (Nano-CT) of a real sample of CL. Then, the multiphysics dynamic distribution (MPDD) simulation, which is inherently a multiscale approach made of a combination of pore-scale and homogeneous models, was conducted on the reconstructed microstructure model to compute the corresponded heat and mass transport, electrochemical reactions, and water phase-change processes. Considering a computational domain with the size of 4 um and cube shape, this model consisting of mass and heat transport as well as electrochemical reactions reached a stable solution within 3 s as the convergence time. In the presence of sufficient oxygen, proton conduction was identified as the dominant factor determining the strength of the electrochemical reaction. Additionally, it was concluded that current density, temperature, and the distribution of water all exhibit similar distribution trends, which decrease from the interface between CL and the proton-exchange membrane to the interface between CL and the gas-diffusion layer. The present study not only provides an in-depth understanding of the mass and heat transport and electrochemical reaction in the CL microstructure, but it also guides the optimal design and fabrication of CL components and structures, such as improving the local structure to reduce the number of dead pores and large agglomerates, etc.

Highly efficient multiplex base editing: One-shot deactivation of eight genes in Shewanella oneidensis MR-1

Obtaining electroactive microbes capable of efficient extracellular electron transfer is a large undertaking for the scalability of bio-electrochemical systems. Inevitably, researchers need to pursue the co-modification of multiple genes rather than expecting that modification of a single gene would make a significant contribution to improving extracellular electron transfer rates. Base editing has enabled highly-efficient gene deactivation in model electroactive microbe Shewanella oneidensis MR-1. Since multiplexed application of base editing is still limited by its low throughput procedure, we thus here develop a rapid and efficient multiplex base editing system in S. oneidensis. Four approaches to express multiple gRNAs were assessed firstly, and transcription of each gRNA cassette into a monocistronic unit was validated as a more favorable option than transcription of multiple gRNAs into a polycistronic cluster. Then, a smart scheme was designed to deliver one-pot assembly of multiple gRNAs. 3, 5, and 8 genes were deactivated using this system with editing efficiency of 83.3%, 100% and 12.5%, respectively. To offer some nonrepetitive components as alternatives genetic parts of sgRNA cassette, different promoters, handles, and terminators were screened. This multiplex base editing tool was finally adopted to simultaneously deactivate eight genes that were identified as significantly downregulated targets in transcriptome analysis of riboflavin-overproducing strain and control strain. The maximum power density of the multiplex engineered strain HRF(8BE) in microbial fuel cells was 1108.1 mW/m², which was 21.67 times higher than that of the wild-type strain. This highly efficient multiplexed base editing tool elevates our ability of genome manipulation and combinatorial engineering in Shewanella, and may provide valuable insights in fundamental and applied research of extracellular electron transfer.

RGB Tricolor and Multimodal Dynamic Optical Information Encryption and Decoding for Anti-Counterfeiting Applications

Conventional optical anti-counterfeiting strategies are based on the single-color emission, which are easily deciphered and thus greatly limited in the application of information security. Herein, a multimodal dynamic optical information coding with red, green, and blue (RGB) tricolors has been developed by photoluminescence (PL), persistent luminescence (PersL), thermally stimulated luminescence (TSL), and thermally stimulated persistent luminescence (TSPL). The BaSi₂O₂N₂:Eu²⁺ phosphors with a blue emission peak at 494 nm were used as the crucial blue optical information coding material and exhibited the distinctive response properties to light, heat, and force stimuli with intrinsic trap depths of 0.674 and 0.82 eV. More importantly, by combining the red Sr₂Si₅N₈:Eu²⁺,Dy³⁺ and green SrSi₂O₂N₂:Eu²⁺,Dy³⁺ nitride phosphors, a RGB tricolor and multimodal strategy has been successfully developed for anti-counterfeiting applications. The "RGB tricolor flower" with RGB emissions is given as a typical example to achieve the dynamic display of optical information encryption and decoding through the various PL, PersL, TSL, and TSPL modes. Finally, the traditional quick response (QR) code mechanism has been integrated into the design of multi-information encrypted RGB tricolor anti-counterfeiting devices with different identifiabilities of the encrypted information in natural light, PL, PersL, TSL, and TSPL modes. The laminated layers of RGB QR code patterns containing different specific information, such as "DLPU" and "116034", can be effectively recognized in the corresponding modes. The design strategy of RGB tricolor and multimodal optical information encryption and decoding devices in this work greatly improves the security level of advanced optical information technologies and extends the potential applications in dynamic anti-counterfeiting fields.

Hospital procedural volume and clinical outcomes for transcatheter aortic valve replacement – US nationwide readmission database, 2016–2019

Background

The number of hospitals offering transcatheter aortic valve replacement (TAVR) programs has increased exponentially in the United States over past several years. Multiple prior studies indicate relationship between hospital volume and clinical outcomes for various cardiac procedures.

Purpose

The association between the hospital procedural volume and clinical outcomes for TAVR is yet poorly understood. In this study, we aim to examine the in-hospital outcomes after TAVR stratified by hospital volume within a nationally representative, large database.

Methods

The National Readmission Database (NRD) 2016–2019 was used to identify hospitals with established TAVR programs (performing ≥20 TAVRs/year). Based on annualized procedural volume of transfemoral TAVR, hospitals were stratified into tertiles of low, medium, and high volume TAVR centers. Rates of adverse in-hospital events (death, cardiac arrest, stroke, vascular complications, and permanent pacemaker), 30-day mortality, and 30-day readmission rates were examined. Multivariate logistic regression analysis was performed to compare overall outcomes following TAVR in low-, medium-, and high-volume centers; adjusted for baseline characteristics and comorbidity burden.

Results

Of 71 million discharge records reviewed, a total of 232,581 patients underwent transfemoral TAVR between 2016–2019. Of all the TAVR cases, 77,183 (33.2%), 75,987 (32.7%), and 79,411 (34.1%) were performed at low-, medium-, and high-volume hospitals respectively. The median number of annual TAVR procedures was 91, 229, and 456 in low-, medium-, and high-volume centers respectively. Adjusted in-hospital mortality was significantly higher in low-volume (OR: 1.40, 95% CI: 1.21–1.62, p&lt;0.01) and medium-volume (OR: 1.29, 95% CI: 1.11–1.50, p&lt;0.01) hospitals compared with high-volume centers. Similarly, adjusted 30-day mortality (OR: 1.45, 95% CI: 1.27–1.66, p&lt;0.01), 30-day readmission rates (OR: 1.11, 95% CI: 1.05–1.18, p&lt;0.01), and in-hospital cardiac arrest (OR: 1.20, 95% CI: 1.08–1.33, p&lt;0.01) were significantly higher for centers in the lowest-volume tertile compared with those in the highest-volume tertile. There were no significant differences in hospital length of stay (mean, 4.3±6.5 days), in-hospital stroke, acute kidney injury, vascular complications, need for permanent pacemaker, or mechanical circulatory support post-TAVR between the three groups.

Conclusion

In the United States, an inverse volume-mortality relationship was observed for transfemoral TAVR procedures from 2016 through 2019. Mortality and readmission rates at 30 days post-TAVR were significantly higher at low-volume hospitals compared with high-volume hospitals. Further research focusing at establishing protocols and standardized training programs may help mitigate the discrepancy in TAVR outcomes amongst hospitals with discrepant procedural volume.

Funding Acknowledgement

Type of funding sources: None.

Applications of machine learning to a compact magnetic spectrometer for high repetition rate, laser-driven particle acceleration

Accurately and rapidly diagnosing laser-plasma interactions is often difficult due to the time-intensive nature of the analysis and will only become more so with the rise of high repetition rate lasers and the desire to implement feedback on a commensurate timescale. Diagnostic analysis employing machine learning techniques can help address this problem while maintaining a high degree of accuracy. We report on the application of machine learning to the analysis of a scintillator-based electron spectrometer for experiments on high intensity, laser-plasma interactions at the Colorado State University Advanced Lasers and Extreme Photonics facility. Our approach utilizes a neural network trained on synthetic data and tested on experiments to extract the accelerated electron temperature. By leveraging transfer learning, we demonstrate an improvement in the neural network accuracy, decreasing the network error by 50%.

Brassinosteroids enhance resistance to manganese toxicity in Malus robusta Rehd. via modulating polyamines profile

Manganese (Mn) toxicity in soil is a widely observed phenomenon, which seriously restricts growth, quality, and yield of various crops and fruits including apples. However, mechanisms underlying the regulation of polyamines (PAs) by brassinosteroids (BRs) to improve tolerance to Mn stress are still unclear. In this study, we investigated the effects of 2,4-epibrassinolide (EBL; a BR) on the expression of genes involved in BR signaling pathway, Mn accumulation, PAs-mediated responses (PA precursor levels, metabolic enzymes, and genes), and growth parameters in Mn-stressed Malus robusta Rehd. EBL application significantly modulated the expressions of genes related to BR signaling (MdBRI, MdBSK, etc.) and reduced Mn accumulation, along with improving the rate of increase in root length and plant height, relative water content, chlorophyll content, maximum photochemical efficiency of PSII (Fv/Fm), and actual photochemical efficiency (Φ_PSII) and decreasing electrical conductivity. Furthermore, EBL application significantly reduced putrescine (Put) accumulation and increased spermine (Spm) content and (Spd + Spm)/Put ratio. EBL weakened ornithine (Orn) pathway, decreased ornithine decarboxylase (ODC) activity, and increased biosynthesis of Spm from Put via elevating the PA oxidase (PAO) activity and expression of MdSPDS, MdSPMS, and MdPAO. The trends for free, PS-conjugated, and PIS-bound PAs were similar to that of total PAs, except that no significant change was observed in free Spm, PS-conjugated Spd, and Spm, as well as PIS-bound Spd. This study revealed that BR-regulated PAs help in mitigating Mn toxicity and clarified the mechanisms of regulation of PAs by BRs in apple trees.

Homogeneous, Micron-Scale High-Energy-Density Matter Generated by Relativistic Laser-Solid Interactions

Short-pulse, laser-solid interactions provide a unique platform for studying complex high-energy-density matter. We present the first demonstration of solid-density, micron-scale keV plasmas uniformly heated by a high-contrast, 400 nm wavelength laser at intensities up to 2×10^{21}  W/cm^{2}. High-resolution spectral analysis of x-ray emission reveals uniform heating up to 3.0 keV over 1  μm depths. Particle-in-cell simulations indicate the production of a uniformly heated keV plasma to depths of 2  μm. The significant bulk heating and presence of highly ionized ions deep within the target are attributed to the few MeV hot electrons that become trapped and undergo refluxing within the target sheath fields. These conditions enabled the differentiation of atomic physics models of ionization potential depression in high-energy-density environments.

Tailoring head-tail mesoporous silica nanoparticles for enhanced gene transfection

Plasmid DNA (pDNA) delivery has attracted extensive research interest due to its great potential in gene therapy. The design of efficient nano-vectors to promote cellular delivery and transfection of gene molecules is the key to success. Compared to conventional nanocarriers with spherical geometry, asymmetric nanoparticles have been well documented showing enhanced cellular uptake and drug delivery capability. However, the impact of asymmetric nanostructures on pDNA binding and following intracellular delivery performance has been less reported. Herein, asymmetric head-tail mesoporous silica nanoparticles (HTMSNs) with tailored tail lengths were synthesized and employed as nano-vectors for pDNA delivery. The nanostructures of HTMSNs were carefully characterized by electron tomography. The pDNA binding, cellular uptake and gene transfection capabilities of engineered asymmetric nanoparticles were compared with symmetric dendritic mesoporous silica nanoparticles (DMSNs). The results showed that the asymmetric morphology of nanoparticles promoted pDNA binding and cell internalization, where HTMSNs-66 with a specific tail length of 66 nm achieved the highest transfection efficiency. This study reveals the impact of asymmetric nanostructure on DNA interaction, and provides guidance in future designs of non-viral nano-vectors for efficient gene delivery.

Genome Editing by CRISPR/Cas12 Recognizing AT-Rich PAMs in Shewanella oneidensis MR-1

Homologous recombination-mediated genomic editing is urgently needed to obtain high-performance chassis of electroactive microorganisms. However, the existing tools cannot meet the requirement of genome-wide editing in Shewanella oneidensis. Here, we develop different CRISPR-Cas systems that are ideal to be employed in AT-rich sequences as the supplements to Cas9. AsCpf1 and BhCas12b show low cell toxicity and superior ability to target sequences and are thus screened out in S. oneidensis MR-1. The PAMs of AsCpf1 and BhCas12b are 5'-TTTV-3' and 5'-ATTN-3'. For gene deletion, ∼1-kb gene is knocked out and the editing efficiency is 41.67% by BhCas12b-mediated system. For gene replacement, endogenous promoter of nagK was substituted to a constitutive promoter with the efficiency of 25% through BhCas12b system. For gene insertion, the integration efficiency was up to 94.4% and 83.9% via CRISPR-BhCas12b and AsCpf1 tools. This study implies a great potential of CRISPR-BhCas12b/AsCpf1 systems recognizing AT-rich PAMs for genomic editing in S. oneidensis to facilitate multifaceted gene manipulation.

The effects of COVID-19 transmission on environmental sustainability and human health: Paving the way to ensure its sustainable management

The transmission dynamics and health risks of coronavirus disease 2019 (COVID-19) pandemic are inextricably linked to ineract with environment, climate, air pollution, and meteorological conditions. The spread of COVID-19 infection can thus perturb the 'planetary health' and livelihood by exerting impacts on the temporal and spatial variabilities of environmental pollution. Prioritization of COVID-19 by the health-care sector has been posing a serious threat to economic progress while undermining the efforts to meet the United Nations' Sustainable Development Goals (SDGs) for environmental sustainability. Here, we review the multifaceted effects of COVID-19 with respect to environmental quality, climatic variables, SDGs, energy resilience, and sustainability programs. It is well perceived that COVID-19 may have long-lasting and profound effects on socio-economic systems, food security, livelihoods, and the 'nexus' indicators. To seek for the solution of these problems, consensus can be drawn to establish and ensure a sound health-care system, a sustainable environment, and a circular bioeconomy. A holistic analysis of COVID-19's effects on multiple sectors should help develop nature-based solutions, cleaner technologies, and green economic recovery plans to help maintain environmental sustainability, ecosystem resilience, and planetary health.

[Correlation analysis of clock genes and MEN2 medullary thyroid carcinoma]

Objective: To investigate the correlation between CLOCK and BMAL1 genes and MEN2 medullary thyroid carcinoma (MTC). Methods: Thirteen cases with MEN2 MTC and thirteen cases with non-MEN2 MTC were selected who were treated in the Yantai Yuhuangding Hospital between January 2013 and September 2021. Clinical indicators such as blood calcitonin level, tumor diameter and metastatic lymph node of patients were collected. The expression differences of CLOCK and BMAL1 between MEN2 MTC and para-carcinoma tissue as well as between MEN2 MTC and non-MEN2 MTC were detected by immunohistochemistry and qPCR. The correlation between lymph node metastasis and CLOCK or BMAL1 expression was analyzed. Protein-protein interaction (PPI) network analysis combined with qPCR and correlation analysis was used to explore the expression regulation relationship between RET and circadian clock genes. The rhythm disorder of MEN2 cells was verified by lipopolysaccharide cell stimulation experiment after dexamethasone rhythm synchronization. Results: MEN2 MTC exhibited typical RET gene mutation. The mean blood calcitonin level, the tumor diameter and the number of metastatic lymph nodes of patients with MEN2 MTC were higher than those of patients with non-MEN2 MTC (t value was 2.76, 2.53, 2.26, all P<0.05). Immunohistochemical results showed that the expression levels of CLOCK and BMAL1 in MEN2 MTC were higher than those in non-MEN2 MTC, while negatively expressed in para-cancerous thyroid follicle. qPCR displayed that the expression of CLOCK gene in cancer tissues was higher than that in non-MEN2 MTC and para-cancerous tissues (t value was 2.68 and 2.86, all P<0.05); the expression of BMAL1 gene in MEN2 MTC was higher than that in non-MEN2 MTC and para-cancerous tissues (t value was 2.21 and 2.35, all P<0.05). Correlation analysis showed that the expression levels of CLOCK and BMAL1 genes were positively correlated with the number of lymph node metastases in patients with MEN2 MTC (r=0.65, P<0.001; r=0.52, P=0.005). PPI network analysis indicated that the expression of CLOCK gene was positively correlated with the abnormal expression of RET gene (r=0.96, P<0.001). With lipopolysaccharide to stimulate cultured cells in vitro after dexamethasone rhythm synchronization, the expressions of CLOCK and BMAL1 in MEN2 MTC cells (0.47±0.22 and 2.60±1.48) at 12 hours of synchronization were significantly lower than those in para-cancerous tissues (1.70±1.62 and 8.23±2.52), the difference was statistically significant(t=5.04, P=0.007; t=3.34, P=0.029). Conclusion: CLOCK and BMAL1 are correlated with the occurrence and development of MEN2 MTC, and may be potential targets for the development of new therapeutic strategies for MEN2 MTC.

Molecular response and developmental speculations in metamorphosis of the veined rapa whelk, Rapana venosa (Valenciennes, 1846)

Metamorphosis is the short developmental stage characterized by dramatic ontogenetic changes that occurs in most animals. However, this important process remains largely unclear in marine invertebrates. In this study, we performed the sequential RNA sequencing of a representative mollusk, the rapa whelk (Rapana venosa), that is undergoing metamorphosis and conducted differential gene expression analysis and weighted gene co-expression network analysis (WGCNA) to investigate the overall and dynamic transcriptome responses. The results revealed that the expression of cytochrome P450 2A and 3A were upregulated during metamorphosis, while the expression of H/ACA ribonucleoproteins increased 4 h after metamorphosis induction (M4 stage), indicating that R. venosa mainly responded to the pelagobenthic changes. At the M24 stage, the enrichment of V-type proton ATPase and insulin indicated the complete development of secretory organs and initiation of hormone secretion. Furthermore, at the M48 stage, the enrichment of zinc metalloproteinase and conotoxin indicated a well-developed predation system that requires exogenous nutrition. Finally, during the PL stage, the genes associated with growth control were highly enriched, implying that R. venosa had completed metamorphosis and has entered the period of rapid growth. Therefore, our study provides useful transcriptomic resources for R. venosa and contribute new insights that may assist in elucidating the mechanisms underlying metamorphosis in marine invertebrates. This article is protected by copyright. All rights reserved.