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Government collaboration tasks are integral for grassroots governance and essential for government administration. Large-scale government collaboration tasks often involve multiple departments working together to solve complex tasks that require handling large amounts of data. However, existing offline processes make it difficult to manage complex collaboration scenarios and obtain timely execution results. We introduce the concept of a spatio-temporal task tree and propose a log-based incremental update method for updating statistical values in the tree structure to fulfill the need for real-time aggregation analysis of cross-temporal task execution situations. The spatio-temporal task tree fosters collaboration across various departments and organizational hierarchies to execute complex and large-scale tasks in government effectively. By flexible adaptations to different business models, this framework addresses the shortcomings of conventional systems in promoting inter-organizational collaboration. The log-based incremental update method for calculating statistical values within a tree structure allows for the updating of multi-dimensional data statistics in seconds. This approach effectively decreases computational expenses, enhances query efficiency, and improves real-time computation response. Results from experiments demonstrate the feasibility and high availability of the proposed approach, showcasing their potential to address the challenges associated with large-scale collaborative tasks in government affairs. [ABSTRACT FROM AUTHOR]

The manipulation on dual‐/multi‐band multiphoton pumped lasing in a single microcrystal is critically essential and technologically needed, which still faces difficulties such as the lack of effective approaches to integrate various multiphoton gain media while avoiding undesirable energy transfer processes. Herein, for the first time, the switchable dual‐band two‐photon pumped (TPP) lasing is realized by constructing composition‐graded metal–organic frameworks (MOFs) heterostructures. The epitaxial growth strategy is adopted for the development of heterostructures, which achieves the hierarchical encapsulation of different linear dye molecules along the 1D channels, thereby effectively restraining unnecessary intermolecular interactions. Strong position dependence of emission response in such deliberately designed heterostructures is observed, enabling a switchable dual‐band TPP polarized lasing through precise selection on excited positions. Furthermore, the excitation wavelength dependence of emission also endows such heterostructures with switchable optical behaviors (two‐photon fluorescence or lasing) via controlling the incident wavelength. The novel heterostructures for switchable dual‐band TPP lasing with uniquely position‐dependent and excitation wavelength‐dependent features open an avenue to develop controllable miniaturized lasers and make such MOFs based micro‐lasers promising for practical applications in future optoelectronic devices. [ABSTRACT FROM AUTHOR]

Halide perovskite nanocrystals (NCs) are a unique class of NCs with novel properties distinct from those of traditional semiconductor NCs. These exceptional properties of defect tolerance, large absorption coefficients, high brightness, and narrow emission linewidths stem from their atypical band structure. Their facile synthesis and broad colour tunability have attracted widespread interest for application in light emitting devices and lasers. One fledging niche area is the field of multiphoton excited emission where their giant nonlinear optical action cross-sections are highly favorable for imaging applications. This Frontier article examines the state-of-the-art in perovskite NCs for multiphoton applications from the materials science and physics perspectives that include their synthesis and nonlinear optical characterization. Opportunities and challenges of these exceptional NCs as potential fluorescent labels for multiphoton deep tissue microscopy are also highlighted. [ABSTRACT FROM AUTHOR]

The epidemic diarrheal disease cholera is caused by the Gram-negative bacterium Vibrio cholerae. V. cholerae virulence factors include the toxin-coregulated pilus (TCP) and cholera toxin, which are major factors responsible for host colonization and production of diarrhea. Expression of cholera toxin and TCP genes is controlled by the ToxR regulon. The ToxR regulon includes the transcriptional activators ToxR, TcpP, and ToxT. ToxT directly initiates transcription of the cholera toxin and TCP genes. TcpP and ToxR are necessary for expression of toxT. TcpP and ToxR activity requires TcpH and ToxS, respectively. Additionally, ToxR is able to directly initiate transcription of the cholera toxin genes independent of TcpP and ToxT. TCP is required early in infection to colonize the small intestine, then cholera toxin is expressed later in infection to produce diarrhea. We tested whether stringent response, the low nutrient stress response, was involved in regulation of virulence genes. Using an infant mouse model, we found that V. cholerae strains with deletions of the stringent response genes were unable to colonize the small intestine. We further tested these stringent response-null mutants and found that stringent response was necessary for TCP expression, although effects on cholera toxin expression were not significant. We then tested whether stringent response regulation of TCP occurred through the ToxR regulon. We found that stringent response induced toxT and tcpPH expression, while repressing toxRS. This differential regulation of ToxR and TcpP may explain the differential expression of TCP and cholera toxin in vivo. [ABSTRACT FROM AUTHOR]

Multi-band microlasers based on single microcrystalline materials with Fabry-Perot (F-P) cavities are critically and technologically essential. Here, we demonstrate simultaneous dual-band lasing output (615 and 685 nm) in metal-organic frameworks (MOFs) and organic dyes hybrid single crystals, which support F-P resonances. Through a two-step assembly strategy, two different types of cationic pyridinium hemicyanine dye molecules can be encapsulated into the channel pores of anionic bio-MOF-1-2Me successfully. In addition, the employment of the host-guest system significantly increases the dye loading, enhances luminescent efficiency, and diminishes the aggregation-caused quenching (ACQ) effect in the resultant MOFs/dye composites. This finding not only combines the characteristic of MOFs materials with excellent luminescent properties of organic dyes, but also points out a simple and promising strategy to design multi-band microlasers based on F-P mechanism, opening a low-cost avenue for the rational design of miniaturized lasers in the future. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) have emerged as particularly exciting inorganic–organic hybrid porous materials which can be simply self-assembled from their corresponding inorganic metal ions/clusters with organic linkers. MOFs can combine the inherent physical and chemical properties of both inorganic and organic photonic units due to their inorganic–organic hybrid nature. Furthermore, the pores within MOFs can also be utilized to encapsulate a large number of guest species as photonic units. The vast combination possibilities, synergistic effects, as well as controllable and ordered arrangements of multiple photonic units (MPUs) have distinguished MOFs from other inorganic and organic photonic materials and enabled them to be a promising platform to realize novel photonic functional applications. In this review, we summarize the recent and important progress in the design and construction of photonic MOFs, as well as their various applications in luminescence sensing, white-light emission, photocatalysis, nonlinear optics, lasing devices, data storage, and biomedicine. In addition, we highlight the construction strategy and the synergistic effects of MOFs towards achieving high performance and novel photonic functions. Finally, we also outline the challenges in these fields and put forward the prospects and directions for future development. [ABSTRACT FROM AUTHOR]

Due to the periodically physical/chemical environment and high-efficient confinement effect of the metal-organic framework (MOF) only possessing 1D channels, the authors realize periodically and highly aligned dye molecule integration within the MOF hybrid material ZJU-68⊃DMASM. Such molecule integration can provide an opportunity to directly determine 4-[ p-(dimethylamino)styryl]-1-methylpyridinium (DMASM) molecules in the MOF channels by electron density mapping using X-ray diffraction data. Furthermore, combining the anisotropic emission property of such molecule integration and the perfect crystal morphology of ZJU-68 serving as the natural resonant cavity, the authors obtain a single-mode linearly polarized laser excited by light ranging from visible to near-infrared. [ABSTRACT FROM AUTHOR]

The first luminescent two-dimensional MOF nanosheets NTU-9-NS Ti2(HDOBDC)2(H2DOBDC) (H2DOBDC = 2,5-dihydroxyterephthalic acid) fabricated via top-down delamination have been realized for the highly sensitive sensing of Fe3+ with a fast response. The highly dispersive nature and highly accessible active sites on the surface of the 2D NTU-9-NS nanosheets enable them to have close contact with targeted metal ions, which leads to the highly sensitive sensing of Fe3+ ions, with a fast response time within seconds and the best detection limit performance of 0.45 μM among MOF materials. The fast response and highly sensitive Fe3+ sensing based on the NTU-9-NS nanosheets sensor material highlights the promise of the two-dimensional MOF nanosheet approach for luminescent sensing applications. This work contributes to the development of research on two-dimensional MOF nanosheets materials with targeted and specific recognition for the application of biological and environmental luminescent sensors. [ABSTRACT FROM AUTHOR]

Single crystal perovskite microplates are fundamentally and technologically very important to developing high‐order (n ≥ 3) multiphoton excitation. This study reports the preparation of high‐quality single crystal perovskite microplates through the controlled release of lead ions from the confined species within a metal–organic framework. The resulting free‐standing MAPbBr3 (MA = CH3NH3+) and CsPbBr3 single crystals of rectangular microplates exhibit excellent multiphoton excitation behaviors, as demonstrated in their five‐photon‐excited photoluminescence and three‐photon‐pumped stimulated emission with the threshold of 159 mJ cm−2, providing the promise of exploring high‐quality single crystal perovskite microplates for functional optoelectronic and photonics applications. [ABSTRACT FROM AUTHOR]

Organic lasers have become an important research and application target for the development of optoelectronics and future photonics due to their ease of preparation and miniaturization, low threshold, and wideband tunability, as well as large optical and nonlinear optical cross sections. Recently, the metal–organic framework (MOF) based organic microlasers have received increasing research attention because they not only achieve high gain concentrations while minimizing the common aggregation‐caused quenching effect of organic luminescence systems, but also can optimize and even control the output performance of the laser by manipulating the interaction between the framework and the gain molecules. In this review, the latest advances in MOF‐based organic lasers are explored and insights into future trends are given, providing useful guidance for the design and preparation of new‐type lasers. [ABSTRACT FROM AUTHOR]