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Spiders are an abundant group of natural enemies preying on insect pests in agroecosystem. But their potential in biological control has not been fully realized due to difficult mass production. One hindrance is the intense intraspecific aggression in spiders. Neurotransmitters such as serotonin play important roles in modulating aggression. Here, we investigated the regulatory function of serotonin (5‐hydroxytryptamine [5‐HT]) signaling in the intraspecific aggression in a wandering spider Pardosa pseudoannulata (Araneae, Lycosidae). The aggression was quantified with 5 escalated aggression behaviors as approach, chasing, lunging, boxing, and biting. Virgin (VG) females exhibited higher aggression levels but less 5‐HT content than post‐reproductive (PR) females. Systemic increase of 5‐HT via 5‐HT injection decreased aggression, while decrease of 5‐HT via RNA interference (RNAi) of the tryptophan hydroxylase gene, increased aggression. The involvement of the four 5‐HT receptors were determined via individual or combined RNAi. Co‐RNAi of the three 5‐HT1 genes increased overall aggression with decreased incidents of approach, chasing, lunging, and increased biting. RNAi of 5‐HT1B decreased approach and increased biting, whereas RNAi of 5‐HT1A or 5‐HT1C did not affect aggression. RNAi of 5‐HT7 decreased approach only. Therefore, different 5‐HT receptor types contribute to different aspects of the inhibitory effects of 5‐HT on aggression and provide several pharmacological targets for manipulating spider aggression. 5‐HT injection did not affect spiders’ predation on their insect prey, the brown planthopper Nilaparvata lugens. The findings reveal 1 neuronal mechanism regulating intraspecific aggression in spiders and provide an insight in developing aggression suppression strategies for spider mass rearing. [ABSTRACT FROM AUTHOR]

Seagrass meadows are important marine ecosystems in coastal areas, offering ecological and economic services to the mankind. However, these ecosystems are facing declines due to climate changes and human activities. Rhizosphere-associated microbiomes play critical roles in the survival and adaptation of seagrasses. While prior studies have explored the general microbial communities and their roles in seagrass meadows, there is a gap in understanding the specific rhizosphere microbiomes of different seagrass species and their interdependent relationships. Our study analyzed the microbial community composition and their metabolism in the rhizosphere of Ruppia sinensis (RS), Zostera japonica (ZJ), and Zostera marina (ZM) obtained from the coastal area of Shandong, China, using high throughput and metagenome sequencing. We found that Rhodobacteraceae, Desulfocapsaceae, and Sulfurovaceae were enriched in RS, ZJ, and ZM samples, respectively, compared with the other two seagrass species, and the bacterial connections were decreased from RS to ZM and ZJ samples. The abundances of nirKS and norBC , mediating denitrification, were higher in RS samples with 2.38% ± 0.59% and 2.14% ± 0.24%, respectively. RS samples also showed a higher level of genes in assimilatory sulfate reduction but lower levels in dissimilatory sulfate reduction and oxidation, with a greater ability to convert sulfide into L-cysteine and acetate. Metagenome-assembled genomes from metagenome of RS rhizosphere had a higher diversity and were assigned to eight phyla. Our study could provide a typical project to analyze the bacterial community structures and metabolic functions in the rhizosphere microbiomes of different seagrasses., Importance: Seagrasses are indispensable in marine ecosystems, offering numerous critical services, with their health significantly influenced by associated rhizosphere microbiomes. Although studies have investigated the microbial communities and their ecological roles in seagrass meadows, the correlations between rhizosphere microbiome and seagrass species from a particular geographic region are limited. Some studies concentrated on the bacterial composition within the rhizosphere of various seagrasses, but the functional aspects of these microbiomes remain unexplored. Our research delves into this void, revealing that Ruppia sinensis , Zostera japonica , and Zostera marina host diverse bacterial community in the composition, connections, functions, and metabolism, such as nitrogen and sulfur metabolism. Our study revealed that seagrass species play an important role in shaping the rhizosphere microbiomes in an equivalent environment, emphasizing the importance of seagrass species in shaping the rhizosphere microbial communities.

Coral reefs are declining due to the rising seawater temperature. Bacteria within and surrounding corals play key roles in maintaining the homeostasis of the coral holobiont. Research on coral-related bacteria could provide benefits for coral reef restoration. During the isolation of coral-associated bacteria, a Gram-stain-negative, motile bacterium (D5M38 T ) was isolated from seawater surrounding corals in Daya Bay, Shenzhen, PR China. Phylogenetic analysis revealed that strain D5M38 T represents a novel species in the genus Cognatishimia . The temperature range for strain D5M38 T growth was 10-40 °C, and the optimum temperature was 37 °C. The salinity range for the growth of this isolate was from 0 to 4.0 %, with an optimal salinity level of 0.5 %. The pH range necessary for strain D5M38 T growth was between pH 5.0 and 9.0, with an optimal pH being 7.5. The predominant fatty acid was summed feature 8 (65.0 %). The major respiratory quinone was Q-10. The DNA G+C content was 56.8 %. The genome size was 3.88 Mb. The average nucleotide identity (ANI), average amino acid identity (AAI) and digital DNA-DNA hybridization (dDDH) values between strain D5M38 T and its two closest neighbours, Cognatishimia activa LMG 29900 T and Cognatishimia maritima KCTC 23347 T , were 73.2/73.6%, 73.2/73.6% and 19.7/19.5%, respectively. Strain D5M38 T was clearly distinct from its closest neighbours C. activa LMG 29900 T and C. maritima KCTC 23347 T , with 16S rRNA gene sequence similarity values of 97.5 and 97.3 %, respectively. The phylogenetic analysis, along with the ANI, AAI, and dDDH values, demonstrated that strain D5M38 T is a member of the genus Cognatishimia , and is distinct from the other two recognized species within this genus. The physiological, biochemical and chemotaxonomic characteristics also supported the species novelty of strain D5M38 T . Thus, strain D5M38 T is considered to be classified as representing a novel species in the genus Cognatishimia , for which the name Cognatishimia coralii sp. nov. is proposed. The type strain is D5M38 T (=MCCC 1K08692 T =KCTC 8160 T ).

In view of recent advances in photodegradation of antibiotics, low cost and stable photocatalyst remain rare. In this article, shape-controlled Cu 2 O@CuS nanocubes with the larger specific surface area were successfully prepared via a simple template-engaged strategy. Cu 2 O nanocubes were synthesized through a reduction method as original templates, the core-shelled Cu 2 O@CuS nanocubes were formed by sulphuration with Na 2 S as sulphur source, and the Cu 2 O core can be incompletely removed by Na 2 S 2 O 3 to generate the Cu 2 O@CuS nanoboxes. Herein, hierarchical nanoboxes with two-layered Cu 2 O@CuS were used as photocatalyst materials for photocatalytic degradation of tetracycline (TC). The obtained nanocubes manifested high specific surface area (39.65 m 2  g -1 ) and large pore volume (12.3 cm 3  g -1 ). The degradation performance for TC was investigated in detail, including the effect of parameters such as photocatalyst, pH and catalyst dosage. The results indicated that degradation efficiencies were higher than 90% under visible light. Moreover, the degradation efficiency was 71% after six times.

To achieve practical application of fuel cell, it is vital to develop highly efficient and durable Pt-free catalysts. Herein, we prepare atomically dispersed ZnNC catalysts with Zn-Pyrrolic-N 4 moieties and abundant mesoporous structure. The ZnNC-based anion-exchange membrane fuel cell (AEMFC) presents an ultrahigh peak power density of 1.63 and 0.83 W cm -2 in H 2 -O 2 and H 2 -air (CO 2 -free), and also exhibits long-term stability with more than 120 and 100 h for H 2 -air (CO 2 -free) and H 2 -O 2 , respectively. Density functional calculations further unveil that the Zn-Pyrrolic-N 4 structure is the origin of high activity of as-synthesized ZnNC catalyst, while the Zn-Pyridinic-N 4 moiety is inactive for oxygen reduction reaction (ORR), which successfully explain the puzzle why most Zn-metal-organic framework -derived ZnNC catalysts in previous reports did not present good ORR activity because of their Zn-Pyridinic-N 4 moieties. This work offers a new route for speeding up development of AEMFCs., (© 2022 Wiley-VCH GmbH.)

In this work, nitrogen-doped carbon quantum dots from poly(ethyleneimine) (PQDs) were synthesized by a low-cost and facile one-step hydrothermal method without other reagents. A quantum yield (QY) of up to 23.2% with maximum emission at 460 nm under an excitation wavelength of 340 nm was ascribed to the high nitrogen doping (20.59%). The PQDs selectively form a blue complex with Cu 2+ accompanied by strong quenching of the fluorescence emission. Meanwhile, the PQD-Cu 2+ complex exhibited selective fluorescence recovery and color disappearance on exposure to l-cysteine (Cys). The electron transfer from amino or oxygen groups on the PQDs to Cu 2+ leads to fluorescence quenching, and a chromogenic reaction of the cuprammonium complex results in a color change. The strong affinity between Cys and Cu 2+ causes the detachment of Cu 2+ from the surface of PQDs, so the color of the solution disappears and the fluorescence of PQDs recovers. Under the optimized condition, the proposed sensor was applied to detect Cu 2+ in the linear range of 0-280 μM. A detection limit of 4.75 μM is achieved using fluorescence spectroscopy and 4.74 μM by monitoring the absorbance variation at 272 nm. For Cys detection, the linear range of 0-800 μM with detection limits of 28.11 μM (fluorescence determination) and 19.74 μM (peak shift determination at 272 nm) was obtained. Meanwhile, the PQD-Cu 2+ system exhibits distinguishable responses to other biothiols such as l-glutathione (GSH) and dl-homocysteine (Hcy). Based on the multimode signals, an "AND" logic gate was constructed successfully. Interestingly, besides Cu 2+ , Fe 3+ can also quench the fluorescence of PQDs and the PQD-Fe 3+ system exhibits superior selectivity for Cys detection. Most importantly, the proposed assay is not only simple, cheap, and stable but also suitable for detecting Cu 2+ and Cys in some real samples.

Novel Bi 2 Te 3 /graphene quantum dots (Bi 2 Te 3 /GQDs) hybrid nanosheets with a unique structure that GQDs are homogeneously embedded in the Bi 2 Te 3 nanosheet matrix have been synthesized by a simple solution-based synthesis strategy. A significantly reduced thermal conductivity and enhanced powder factor are observed in the Bi 2 Te 3 /GQDs hybrid nanosheets, which is ascribed to the optimized thermoelectric transport properties of the Bi 2 Te 3 /GQDs interface. Furthermore, by varying the size of the GQDs, the thermoelectric performance of Bi 2 Te 3 /GQDs hybrid nanostructures could be further enhanced, which could be attributed to the optimization of the density and dispersion manner of the GQDs in the Bi 2 Te 3 matrix. A maximum ZT of 0.55 is obtained at 425 K for the Bi 2 Te 3 /GQDs-20 nm, which is higher than that of Bi 2 Te 3 without hybrid nanostrucure. This work provides insights for the structural design and synthesis of Bi 2 Te 3 -based hybrid thermoelectric materials, which will be important for future development of broadly functional material systems.