Comprehensive genomic analysis of the SARS-CoV-2 Omicron variant BA.2.76 in Jining City, China, 2022.

OBJECTIVE: This study aims to analyze the molecular characteristics of the novel coronavirus (SARS-CoV-2) Omicron variant BA.2.76 in Jining City, China. METHODS: Whole-genome sequencing was performed on 87 cases of SARS-CoV-2 infection. Evolutionary trees were constructed using bioinformatics software to analyze sequence homology, variant sites, N-glycosylation sites, and phosphorylation sites. RESULTS: All 87 SARS-CoV-2 whole-genome sequences were classified under the evolutionary branch of the Omicron variant BA.2.76. Their similarity to the reference strain Wuhan-Hu-1 ranged from 99.72 to 99.74%. In comparison to the reference strain Wuhan-Hu-1, the 87 sequences exhibited 77-84 nucleotide differences and 27 nucleotide deletions. A total of 69 amino acid variant sites, 9 amino acid deletions, and 1 stop codon mutation were identified across 18 proteins. Among them, the spike (S) protein exhibited the highest number of variant sites, and the ORF8 protein showed a Q27 stop mutation. Multiple proteins displayed variations in glycosylation and phosphorylation sites. CONCLUSION: SARS-CoV-2 continues to evolve, giving rise to new strains with enhanced transmission, stronger immune evasion capabilities, and reduced pathogenicity. The application of high-throughput sequencing technologies in the epidemic prevention and control of COVID-19 provides crucial insights into the evolutionary and variant characteristics of the virus at the genomic level, thereby holding significant implications for the prevention and control of the COVID-19 pandemic.

Steering Photooxidation of Methane to Formic Acid over A Priori Screened Supported Catalysts.

Efficient methane photooxidation to formic acid (HCOOH) has emerged as a sustainable approach to simultaneously generate value-added chemicals and harness renewable energy. However, the persistent challenge lies in achieving a high yield and selectivity for HCOOH formation, primarily due to the complexities associated with modulating intermediate conversion and desorption after methane activation. In this study, we employ first-principles calculations as a comprehensive guiding tool and discover that by precisely controlling the O2 activation process on noble metal cocatalysts and the adsorption strength of carbon-containing intermediates on metal oxide supports, one can finely tune the selectivity of methane photooxidation products. Specifically, a bifunctional catalyst comprising Pd nanoparticles and monoclinic WO3 (Pd/WO3) would possess optimal O2 activation kinetics and an intermediate oxidation/desorption barrier, thereby promoting HCOOH formation. As evidenced by experiments, the Pd/WO3 catalyst achieves an exceptional HCOOH yield of 4.67 mmol gcat-1 h-1 with a high selectivity of 62% under full-spectrum light irradiation at room temperature using molecular O2. Notably, these results significantly outperform the state-of-the-art photocatalytic systems operated under identical condition.

DeepLINK: Deep learning inference using knockoffs with applications to genomics.

We propose a deep learning-based knockoffs inference framework, DeepLINK, that guarantees the false discovery rate (FDR) control in high-dimensional settings. DeepLINK is applicable to a broad class of covariate distributions described by the possibly nonlinear latent factor models. It consists of two major parts: an autoencoder network for the knockoff variable construction and a multilayer perceptron network for feature selection with the FDR control. The empirical performance of DeepLINK is investigated through extensive simulation studies, where it is shown to achieve FDR control in feature selection with both high selection power and high prediction accuracy. We also apply DeepLINK to three real data applications to demonstrate its practical utility.

Foodborne Pathogen and Microbial Community Differences in Fresh Processing Tomatoes in Xinjiang, China.

The microbes on fresh processing tomatoes correlate closely with diseases, preservation, and quality control. Investigation of the microbial communities on processing tomatoes from different production regions may help define microbial specificity, inform disease prevention methods, and improve quality. In this study, surface microbes on processing tomatoes from 10 samples in two primary production areas of southern and northern Xinjiang were investigated by sequencing fungal internal transcribed spacer and bacterial 16S rRNA hypervariable sequences. A total of 133 different fungal and bacterial taxonomies were obtained from processing tomatoes in the two regions, of which 63 genera were predominant. Bacterial and fungal communities differed significantly between southern and northern Xinjiang, and fungal diversity was higher in southern Xinjiang. Alternaria and Cladosporium on processing tomatoes in southern Xinjiang were associated with plant pathogenic risk. The plant pathogenic fungi of processing tomatoes in northern Xinjiang were more abundant in Alternaria and Fusarium. The abundance of Alternaria on processing tomatoes was higher in four regions of northern Xinjiang, indicating that there is a greater risk of plant pathogenicity in these areas. Processing tomatoes in northern and southern Xinjiang contained bacterial genera identified as gut microbes, such as Pantoea, Erwinia, Enterobacter, Enterococcus, and Serratia, indicating the potential risk of contamination of processing tomatoes with foodborne pathogens. This study highlighted the microbial specificity of processing tomatoes in two tomato production regions, providing a basis for further investigation and screening for foodborne pathogenic microorganisms.

Photocatalysis with atomically thin sheets.

Atomically thin sheets (e.g., graphene and monolayer molybdenum disulfide) are ideal optical and reaction platforms. They provide opportunities for deciphering some important and often elusive photocatalytic phenomena related to electronic band structures and photo-charges. In parallel, in such thin sheets, fine tuning of photocatalytic properties can be achieved. These include atomic-level regulation of electronic band structures and atomic-level steering of charge separation and transfer. Herein, we review the physics and chemistry of electronic band structures and photo-charges, as well as their state-of-the-art characterization techniques, before delving into their atomic-level deciphering and mastery on the platform of atomically thin sheets.

Seasonal patterns, fate and ecological risk assessment of pharmaceutical compounds in a wastewater treatment plant with Bacillus bio-reactor treatment.

Pharmaceutical compounds (PhCs) pose a growing concern with potential environmental impacts, commonly introduced into the environment via wastewater treatment plants (WWTPs). The occurrence, removal, and season variations of 60 different classes of PhCs were investigated in the baffled bioreactor (BBR) wastewater treatment process during summer and winter. The concentrations of 60 PhCs were 3400 ± 1600 ng/L in the influent, 2700 ± 930 ng/L in the effluent, and 2400 ± 120 ng/g dw in sludge. Valsartan (Val, 1800 ng/L) was the main contaminant found in the influent, declining to 520 ng/L in the effluent. The grit chamber and BBR tank were substantially conducive to the removal of VAL. Nonetheless, the BBR process showcased variable removal efficiencies across different PhC classes. Sulfadimidine had the highest removal efficiency of 87 ± 17% in the final effluent (water plus solid phase). Contrasting seasonal patterns were observed among PhC classes within BBR process units. The concentrations of many PhCs were higher in summer than in winter, while some macrolide antibiotics exhibited opposing seasonal fluctuations. A thorough mass balance analysis revealed quinolone and sulfonamide antibiotics were primarily eliminated through degradation and transformation in the BBR process. Conversely, 40.2 g/d of macrolide antibiotics was released to the natural aquatic environment via effluent discharge. Gastric acid and anticoagulants, as well as cardiovascular PhCs, primarily experienced removal through sludge adsorption. This study provides valuable insights into the intricate dynamics of PhCs in wastewater treatment, emphasizing the need for tailored strategies to effectively mitigate their release and potential environmental risks.

Best Practices for Experiments and Reports in Photocatalytic Methane Conversion.

Efficiently converting methane into valuable chemicals via photocatalysis under mild condition represents a sustainable route to energy storage and value-added manufacture. Despite continued interest in this area, the achievements have been overshadowed by the absence of standardized protocols for conducting photocatalytic methane oxidation experiments as well as evaluating the corresponding performance. In this review, we present a structured solution aimed at addressing these challenges. Firstly, we introduce the norms underlying reactor design and outline various configurations in the gas-solid and gas-solid-liquid reaction systems. This discussion helps choosing the suitable reactors for methane conversion experiments. Subsequently, we offer a comprehensive step-by-step protocol applicable to diverse methane-conversion reactions. Emphasizing meticulous verification and accurate quantification of the products, this protocol highlights the significance of mitigating contamination sources and selecting appropriate detection methods. Lastly, we propose the standardized performance metrics crucial for evaluating photocatalytic methane conversion. By defining these metrics, the community could obtain the consensus of assessing the performance across different studies. Moving forward, the future of photocatalytic methane conversion necessitates further refinement of stringent experimental standards and evaluation criteria. Moreover, development of scalable reactor is essential to facilitate the transition from laboratory proof-of-concept to potentially industrial production.

Enabling Specific Photocatalytic Methane Oxidation by Controlling Free Radical Type.

Selective CH4 oxidation to CH3OH or HCHO with O2 in H2O under mild conditions provides a desired sustainable pathway for synthesis of commodity chemicals. However, manipulating reaction selectivity while maintaining high productivity remains a huge challenge due to the difficulty in the kinetic control of the formation of a desired oxygenate against its overoxidation. Here, we propose a highly efficient strategy, based on the precise control of the type of as-formed radicals by rational design on photocatalysts, to achieve both high selectivity and high productivity of CH3OH and HCHO in CH4 photooxidation for the first time. Through tuning the band structure and the size of active sites (i.e., single atoms or nanoparticles) in our Au/In2O3 catalyst, we show alternative formation of two important radicals, •OOH and •OH, which leads to distinctly different reaction paths to the formation of CH3OH and HCHO, respectively. This approach gives rise to a remarkable HCHO selectivity and yield of 97.62% and 6.09 mmol g-1 on In2O3-supported Au single atoms (Au1/In2O3) and an exceptional CH3OH selectivity and yield of 89.42% and 5.95 mmol g-1 on In2O3-supported Au nanoparticles (AuNPs/In2O3), respectively, upon photocatalytic CH4 oxidation for 3 h at room temperature. This work opens a new avenue toward efficient and selective CH4 oxidation by delicate design of composite photocatalysts.

Characterization of CpCaM, a protein potentially involved in the growth of Cryptosporidium parvum.

Cryptosporidium parvum is an important apicomplexan parasite causing severe diarrhea in both humans and animals. Calmodulin (CaM), a multifunctional and universal calcium-binding protein, contributes to the growth and development of apicomplexan parasites, but the role of CaM in C. parvum remains unknown. In this study, the CaM of C. parvum encoded by the cgd2_810 gene was expressed in Escherichia coli, and the biological functions of CpCaM were preliminarily investigated. The transcriptional level of the cgd2_810 gene peaked at 36 h post infection (pi), and the CpCaM protein was mainly located around the nucleus of the whole oocysts, in the middle of sporozoites and around the nucleus of merozoites. Anti-CpCaM antibody reduced the invasion of C. parvum sporozoites by 30.69%. The present study indicates that CpCaM is potentially involved in the growth of C. parvum. Results of the study expand our knowledge on the interaction between host and Cryptosporidium.

Gossypin exert lipopolysaccharide induced lung inflammation via alteration of Nrf2/HO-1 and NF-κB signaling pathway.

Acute Lung Injury (ALI) is a critical medical condition that induces the injury into the lung tissue, resulting in decreased the oxygen levels in the circulation and finally causes the respiratory failure. In this study, we try to made effort for scrutinized the preventive effect of gossypin against lipopolysaccharide (LPS) induced lung inflammation and explore the underlying mechanism. LPS (7.5 mg/kg) was used for induction the lung inflammation in the rats and rats were received the oral administration of gossypin (5, 10 and 15 mg/kg). The wet to dry weight lung ratio and lung index were estimated. The bronchoalveolar lavage fluid (BALF) were collected to determination the inflammatory cells, total protein, macrophages and neutrophils. ELISA kits were used for the estimation of antioxidant, inflammatory cytokines, inflammatory parameters, nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) parameters. Finally, we used the lung tissue for scrutinize the alteration in the lung histopathology. Gossypin treatment significantly (p < .001) reduced the W/D ratio of lung tissue and lung index. Gossypin significantly (p < .001) decreased the total cells, neutrophils, macrophages and total protein in BALF. It is also altered the level of inflammatory cytokines, antioxidant and inflammatory parameters, respectively. Gossypin improved the level of Nrf2 and HO-1 at dose dependent manner. Gossypin treatment remarkably enhance the ALI severity via balancing the structural integrity of lung tissue, decrease the thickness of the alveolar wall, decline the pulmonary interstitial edema, and number of inflammatory cells in the lung tissue. Gossypin is a promising agent for the treatment of LPS induced lung inflammation via altering Nrf2/HO-1 and NF-κB.

2D Transition Metal Dichalcogenides for Photocatalysis.

Two-dimensional (2D) transition metal dichalcogenides (TMDs), a rising star in the post-graphene era, are fundamentally and technologically intriguing for photocatalysis. Their extraordinary electronic, optical, and chemical properties endow them as promising materials for effectively harvesting light and catalyzing the redox reaction in photocatalysis. Here, we present a tutorial-style review of the field of 2D TMDs for photocatalysis to educate researchers (especially the new-comers), which begins with a brief introduction of the fundamentals of 2D TMDs and photocatalysis along with the synthesis of this type of material, then look deeply into the merits of 2D TMDs as co-catalysts and active photocatalysts, followed by an overview of the challenges and corresponding strategies of 2D TMDs for photocatalysis, and finally look ahead this topic.

AaTAS1 and AaMFS1 Genes for Biosynthesis or Efflux Transport of Tenuazonic Acid and Pathogenicity of Alternaria alternata.

Taking tenuazonic acid (TeA) synthetase 1 (TAS1) in Pyricularia oryzae as a reference, the homolog AaTAS1 was first anchored in Alternaria alternata via de novo sequencing. Subsequently, AaMFS1, as a major facilitator superfamily (MFS) protein-encoding gene in the adjacent upstream region, was followed with interest. As hypothesized, AaTAS1 is required for TeA biosynthesis, while AaMFS1 is an efflux pump for the transmembrane transport of TeA. Comparatively, the TeA yield of ΔAaTAS1 and ΔAaMFS1 dropped significantly compared with that of the wild-type strain. Specifically, the A domain of AaTAS1 catalyzed the start of TeA biosynthesis in vitro. Simultaneously, the pathogenicity of ΔAaTAS1 was also significantly decreased. Transcriptome analysis confirmed the abovementioned consistency between the TeA-producing phenotypes and related gene expression. Moreover, the proteins AaTAS1 and AaMFS1 were found present in the cytoplasm, plasma membrane, and intracellular membrane system, respectively, by fluorescence localization. Namely, AaTAS1 was responsible for the biosynthesis of TeA, and AaMFS1 was responsible for the efflux transport of TeA. Certainly, AaTAS1 indirectly regulated the expression of AaMFS1 through the level of synthetic TeA. Overall, data on the novel AaTAS1 and AaMFS1 genes mainly contribute to theoretical advances in mycotoxin biosynthesis and the pathogenicity of phytopathogens to agricultural foods.[Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Elevating Photooxidation of Methane to Formaldehyde via TiO2 Crystal Phase Engineering.

Photocatalytic conversion of methane to value-added products under mild conditions, which represents a long sought-after goal for industrial sustainable production, remains extremely challenging to afford high production and selectivity using cheap catalysts. Herein, we present the crystal phase engineering of commercially available anatase TiO2 via simple thermal annealing to optimize the structure-property correlation. A biphase catalyst with anatase (90%) and rutile (10%) TiO2 with the optimal phase interface concentration exhibits exceptional performance in the oxidation of methane to formaldehyde under the reaction conditions of water solvent, oxygen atmosphere, and full-spectrum light irradiation. An unprecedented production of 24.27 mmol gcat-1 with an excellent selectivity of 97.4% toward formaldehyde is acquired at room temperature after a 3 h reaction. Both experimental results and theoretical calculations disclose that the crystal phase engineering of TiO2 lengthens the lifetime of photogenerated carriers and favors the formation of intermediate methanol species, thus maximizing the efficiency and selectivity in the aerobic oxidation of methane to formaldehyde. More importantly, the feasibility of the scale-up production of formaldehyde is demonstrated by inventing a "pause-flow" reactor. This work opens the avenue toward industrial methane transformation in a sustainable and economical way.

KIMI: Knockoff Inference for Motif Identification from molecular sequences with controlled false discovery rate.

MOTIVATION: The rapid development of sequencing technologies has enabled us to generate a large number of metagenomic reads from genetic materials in microbial communities, making it possible to gain deep insights into understanding the differences between the genetic materials of different groups of microorganisms, such as bacteria, viruses, plasmids, etc. Computational methods based on k-mer frequencies have been shown to be highly effective for classifying metagenomic sequencing reads into different groups. However, such methods usually use all the k-mers as features for prediction without selecting relevant k-mers for the different groups of sequences, i.e. unique nucleotide patterns containing biological significance. RESULTS: To select k-mers for distinguishing different groups of sequences with guaranteed false discovery rate (FDR) control, we develop KIMI, a general framework based on model-X Knockoffs regarded as the state-of-the-art statistical method for FDR control, for sequence motif discovery with arbitrary target FDR level, such that reproducibility can be theoretically guaranteed. KIMI is shown through simulation studies to be effective in simultaneously controlling FDR and yielding high power, outperforming the broadly used Benjamini-Hochberg procedure and the q-value method for FDR control. To illustrate the usefulness of KIMI in analyzing real datasets, we take the viral motif discovery problem as an example and implement KIMI on a real dataset consisting of viral and bacterial contigs. We show that the accuracy of predicting viral and bacterial contigs can be increased by training the prediction model only on relevant k-mers selected by KIMI. AVAILABILITYAND IMPLEMENTATION: Our implementation of KIMI is available at https://github.com/xinbaiusc/KIMI. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Perspectives on Ligand Properties of N-Heterocyclic Carbenes in Iron Porphyrin Complexes.

There has been considerable research interest in the ligand nature of N-heterocyclic carbenes (NHCs). In this work, two six-coordinate NHC iron porphyrin complexes [FeII(TTP)(1,3-Me2Imd)2] (TTP = tetratolylporphyrin, 1,3-Me2Imd = 1,3-dimethylimidazol-2-ylidene) and [FeIII(TDCPP)(1,3-Me2Imd)2]ClO4 (TDCPP = 5,10,15,20-tetrakis(2,6-dichlorophenyl)porphyrin) are reported. Single-crystal X-ray characterizations demonstrate that both complexes have strongly ruffled conformations and relatively perpendicular ligand orientations which are forced by the sterically bulky 1,3-Me2Imd NHC ligands. Multitemperature (4.2-300 K) and high magnetic field (0-9 T) Mössbauer and low-temperature (4.0 K) EPR spectroscopies definitely confirmed the low-spin states of [FeII(TTP)(1,3-Me2Imd)2] (S = 0) and [FeIII(TDCPP)(1,3-Me2Imd)2]ClO4 (S = 1/2). The similarity of 1,3-Me2Imd and imidazole, as well as the well-established correlations between the ligand nature and spectroscopic characteristics of [FeII,III(Porph)(L)2]0,+ (Porph: porphyrin; L: planar base ligand) species, allowed direct comparisons between the pair of ligands which revealed for the first time that NHC has a stronger π-acceptor ability than imidazoles, in addition to its very strong σ-donation.

Hydrogen-rich and hyperoxygenate saline inhibits lipopolysaccharide-induced lung injury through mediating NF-κB/NLRP3 signaling pathway in C57BL/6 mice.

BACKGROUND: Background: Acute lung injury (ALI) is one kind of frequently occurred emergency in Intensive Care Unite with a high mortality. The underlying causes are uncontrolled inflammatory reactions and intractable hypoxemia, which are difficult to control and improve. In the past 10 years, gas medical studies have found that both hydrogen molecules and oxygen molecules have protective effects on acute lung injury by improving inflammatory reactions and hypoxia, respectively. Oxygen is an oxidant and hydrogen is an antioxidant. In this study, we investigated the combined effect of above two-gas molecular on lipopolysaccharide (LPS) -induced acute lung injury. METHODS: To clarify whether the combination of hydrogen and oxygen could increase or cancel out the protective effect, an ALI mice model induced by intraperitoneal injection of LPS was established, and the degree of lung tissue and mitochondria damage was evaluated based on the pathological sections, inflammatory factors, wet-dry ratio, bronchoalveolar lavage fluid (BALF). Immunohistochemistry, electron microscopy, western blotting and other detection methods also used to evaluate the therapeutic effect on acute lung injury model. RESULTS: We observed that the combined protective effect of hydrogen and oxygen was superior to their respective protective effects, and the specific molecular mechanisms of the two therapies might be different. CONCLUSION: Hydrogen plays a more important role in the inflammatory and anti-apoptosis mechanisms, while oxygen improves hypoxia of the body, and thus, its molecular mechanism may be closely associated to the hypoxia pathways.

Genistein reverses the effect of 17ß-estradiol on exacerbating experimental occlusal interference-induced chronic masseter hyperalgesia in ovariectomised rats.

BACKGROUND: Oro-facial pain is more prevalent in women than in men, and oestrogen may underlie this sex difference. Genistein reversed the potentiation of 17ß-estradiol (E2) on glutamate-induced acute masseter nociceptive behaviour, but its role in dental experimental occlusal interference (EOI)-induced chronic masseter hyperalgesia remains unclear. OBJECTIVE: This study aimed to investigate sex differences, and to explore the role and underlying mechanisms of genistein in E2-potentiated EOI-induced chronic masseter hyperalgesia in rats. METHODS: Female and male rats were prepared to compare the sex differences of masseter hyperalgesia induced by EOI using a 0.4-mm-thick metal crown. Female rats were ovariectomised (OVX) and treated with E2 and genistein, followed by EOI. The head withdrawal threshold (HWT) was examined to assess masseter sensitivity. The protein expression of transient receptor potential vanilloid-1 (TRPV1) in the trigeminal ganglion (TG) was detected using western blotting. Immunofluorescence staining was used to reveal the colocalisation of oestrogen receptors (ERs) with TRPV1 and the percentage of TRPV1-positive neurons in the TG. RESULTS: To some extent, female rats displayed enhanced sensitivity to EOI-induced chronic masseter hyperalgesia compared with males. Female rats showed the lowest HWT in the pro-oestrus phase. Pre-treatment with genistein antagonised E2 potentiation in EOI-induced masseter hyperalgesia and blocked the effect of E2 by downregulating TRPV1 protein expression and the percentage of TRPV1-positive neurons in the TG. CONCLUSION: Female rats showed greater masseter hyperalgesia than males under EOI. Genistein antagonised the facilitation of EOI-induced chronic masseter hyperalgesia by E2 probably through inhibiting TRPV1 in the TG.

A Chimeric Conjugate of Antibody and Programmable DNA Nanoassembly Smartly Activates T Cells for Precise Cancer Cell Targeting.

Synthetically directing T-cells against tumors emerges as a promising strategy in immunotherapy, while it remains challenging to smartly engage T cells with tunable immune response. Herein, we report an intelligent molecular platform to engineer T-cell recognition for selective activation to potently kill cancer cells. To this end, we fabricated a hybrid conjugate that uses a click-type DNA-protein conjugation to equip the T cell-engaging antibody with two distinct programmable DNA nanoassemblies. By integrating multiple aptameric antigen-recognitions within a dynamic DNA circuit, we achieved combinatorial recognition of triple-antigens on cancer cells for selective T-cell activation after high-order logic operation. Moreover, by coupling a DNA nanostructure, we precisely defined the valence of the antigen-binding aptamers to tune avidity, realizing effective tumor elimination in vitro and in vivo. Together, we present a versatile and programmable strategy for synthetic immunotherapy.

Exploiting natural variation in crown root traits via genome-wide association studies in maize.

BACKGROUND: Root system architecture (RSA), which is determined by the crown root angle (CRA), crown root diameter (CRD), and crown root number (CRN), is an important factor affecting the ability of plants to obtain nutrients and water from the soil. However, the genetic mechanisms regulating crown root traits in the field remain unclear. METHODS: In this study, the CRA, CRD, and CRN of 316 diverse maize inbred lines were analysed in three field trials. Substantial phenotypic variations were observed for the three crown root traits in all environments. A genome-wide association study was conducted using two single-locus methods (GLM and MLM) and three multi-locus methods (FarmCPU, FASTmrMLM, and FASTmrEMMA) with 140,421 SNP. RESULTS: A total of 38 QTL including 126 SNPs were detected for CRA, CRD, and CRN. Additionally, 113 candidate genes within 50 kb of the significant SNPs were identified. Combining the gene annotation information and the expression profiles, 3 genes including GRMZM2G141205 (IAA), GRMZM2G138511 (HSP) and GRMZM2G175910 (cytokinin-O-glucosyltransferase) were selected as potentially candidate genes related to crown root development. Moreover, GRMZM2G141205, encoding an AUX/IAA transcriptional regulator, was resequenced in all tested lines. Five variants were identified as significantly associated with CRN in different environments. Four haplotypes were detected based on these significant variants, and Hap1 has more CRN. CONCLUSIONS: These findings may be useful for clarifying the genetic basis of maize root system architecture. Furthermore, the identified candidate genes and variants may be relevant for breeding new maize varieties with root traits suitable for diverse environmental conditions.

Investigation into the Phase-Activity Relationship of MnO2 Nanomaterials toward Ozone-Assisted Catalytic Oxidation of Toluene.

Manganese dioxide (MnO2 ), with naturally abundant crystal phases, is one of the most active candidates for toluene degradation. However, it remains ambiguous and controversial of the phase-activity relationship and the origin of the catalytic activity of these multiphase MnO2 . In this study, six types of MnO2 with crystal phases corresponding to α-, ß-, γ-, ε-, λ-, and δ-MnO2 are prepared, and their catalytic activity toward ozone-assisted catalytic oxidation of toluene at room temperature are studied, which follow the order of δ-MnO2  > α-MnO2  > ε-MnO2  > γ-MnO2  > λ-MnO2  > ß-MnO2 . Further investigation of the specific oxygen species with the toluene oxidation activity indicates that high catalytic activity of MnO2 is originated from the rich oxygen vacancy and the strong mobility of oxygen species. This work illustrates the important role of crystal phase in determining the oxygen vacancies' density and the mobility of oxygen species, thus influencing the catalytic activity of MnO2 catalysts, which sheds light on strategies of rational design and synthesis of multiphase MnO2 catalysts for volatile organic pollutants' (VOCs) degradation.