Abstract
Background
Currently, clinical laboratories lack an effective method to differentiate between classical
Klebsiella pneumoniae
(cKP) and hypervirulent
Klebsiella pneumoniae
(hvKP) strains, ...leading to delays in diagnosing and treating hvKP infections. Previous studies have identified
peg-344
,
iroB
,
iucA
,
p
rmpA
,
p
rmpA2
, and siderophores (SP) yields greater than 30 μg/ml as reliable markers for distinguishing hvKP from cKp strains. However, these diagnostic tests were conducted on a relatively small study population and lacked sufficient clinical data support. In this study, hvKP strains were identified by biomarker analysis and the Galleria mellonella model. Combined with in vitro and in vivo experiments, the reliability of clinical identification method of hvKP was verified, which provided an experimental basis for timely diagnosis of hvKP infection.
Results
According to the clinical data, a total of 108 strains of hvKP were preliminary screened. Among them, 94 strains were further identified using PCR analysis of biomarkers and quantitative determination of SP. The high virulence of hvKP was subsequently confirmed through infection experiments on Galleria mellonella. Additionally, susceptibility testing revealed the identification of 58 carbapenem-resistant hvKP (CR-hvKP) strains and 36 carbapenem-sensitive hvKP (CS-hvKP) strains. By comparing molecular diagnostic indexes, molecular characteristics such as high SP production of CR-hvKP were found.
Conclusion
The combination of clinical data and molecular diagnostic index analysis effectively enables the identification of hvKP, particularly CR-hvKP. This study provides a scientific basis for accurate clinical identification and timely treatment of hvKP.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Prospective discrimination of rock instability and fracture is a key problem in mining, slope stability, earthquake triggering, and other research fields. Through the rock fracture experiment, ...scientists put forward the load unload response ratio (referred to as LURR) to detect the non-linear deformation process of the strain stress curve, judge the degree of rock damage and instability fracture, which is accepted worldwide and has been widely used in seismic risk assessment. But, the extraction of response parameters (including strain, energy, well water level, etc.) are faced with many difficulties in actual observation, which makes the application of results uncertain. In this paper, the change of relative wave velocity is proposed as the loading unloading response parameter. Through rock mechanics experiments, a prospective discrimination method of rock instability and fracture process is constructed. The change characteristics of the LURR in the process of rock instability and fracture under stress are studied, the experiment result show that: when approaching the main fracture, the LURR calculated by taking the transverse strain energy as the response quantity obviously rises and fall back, the acoustic emission energy release rate and event rate are close to exponential acceleration process; The LURR by taking the change of relative wave velocity as the response parameter, first decreases, then fluctuates near zero, and rapidly decreases to below zero when it reaches the critical failure. The change combination of the above parameters’ response ratio can effectively judge the process of rock deformation, instability and fracture under stress. Moreover, this study of the load unload response ratio which takes the change of relative wave velocity as the response parameter, makes up the deficiency of the traditional load unload response ratio method in judging the rock instability of the medium under stress.
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•MD simulation can reveal the effect of moisture on interfacial behaviors of geopolymer-aggregate interaction;•Wetting characteristics of aggregate surfaces were elucidated and ...compared.•The interfacial mechanism of geopolymer-aggregate with the participation of moisture was explained.•Mechanical behaviors of geopolymer-water-aggregate interface were investigated using peeling and shearing simulation.
The interaction between geopolymer and aggregate largely determines the mechanical properties and durability of the geopolymer concrete. The effects of moisture on interfacial behavior of geopolymer-aggregate interaction are poorly understood, especially at molecular level. Herein, molecular dynamics (MD) simulation was employed to reveal the interactive behaviors of geopolymer-aggregate interfacial system with the participation of moisture. Full atomistic models adopted for MD simulations were constructed using the sodium aluminum silicate hydrate (N-ASH) gel model and the main chemical components of the aggregates, SiO2 and CaCO3. Then the wetting characteristics of aggregate surfaces, interfacial characteristics and mechanical behaviors of the geopolymer-aggregate interfacial systems containing interfacial moisture were elucidated and compared. It is found that the SiO2 surface is hydrophobic while the CaCO3 surface exhibits hydrophilic characteristics. Interfacial moisture participates in electrostatic interaction, H-bond interaction and coordination interaction in geopolymer-aggregate interface area. Appropriate interfacial water is beneficial to the interfacial interaction of geopolymer-aggregate system, but excessive water will increase the risk of interfacial failure. The interfacial moisture affects the diffusion behavior of water molecules and Na+ ions in geopolymer to the interfacial region, and the formation of H-bonds and coordination bonds at the interface. Mechanically, with the participation of interfacial moisture, the geopolymer-SiO2 interfacial system possesses stronger tensile strength, and a greater risk of shear failure than that of geopolymer-CaCO3. The above atomic-level findings may facilitate a better design and fabrication of geopolymer concrete in engineering.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Insects are the most speciose group of animals, but the phylogenetic relationships of many major lineages remain unresolved. We inferred the phylogeny of insects from 1478 protein-coding genes. ...Phylogenomic analyses of nucleotide and amino acid sequences, with site-specific nucleotide or domain-specific amino acid substitution models, produced statistically robust and congruent results resolving previously controversial phylogenetic relationships. We dated the origin of insects to the Early Ordovician ~479 million years ago (Ma), of insect flight to the Early Devonian (~406 Ma), of major extant lineages to the Mississippian (~345 Ma), and the major diversification of holometabolous insects to the Early Cretaceous. Our phylogenomic study provides a comprehensive reliable scaffold for future comparative analyses of evolutionary innovations among insects.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
Pyrene represents one of the most attractive units for building organic optoelectronic materials. Most pyrene derivatives that have been reported are 1,3,6,8-substituted pyrenes, as these positions ...are active to electrophilic reactions. By utilising Ir-catalysed borylation, which is sterically driven, Marder and co-workers have developed an effective way to synthesise 2-, 4-, 2,7-, and 4,9-substituted pyrenes, and the photophysics of these pyrene derivatives has been investigated. Similar methodology has also been used in the study of perylene and others. This review summarises the Ir-catalysed borylation of pyrene and other aromatic hydrocarbons, as well as their contributions to the development of organic optoelectronics.
We summarized the Ir-catalysed borylation of PAHs, especially pyrene, and the optoelectronic materials generated by following this chemistry. The optoelectronic properties of pyrene derivatives have also been discussed.
In many practical many-objective optimization problems, the computational cost of real evaluation is often high. To solve such problems, surrogate-assisted evolutionary algorithms (SAEAs) are ...effective methods that use low-cost surrogate models to approximate expensive real evaluation and select better-performing individuals for further evaluation. However, existing surrogate models accumulate prediction errors with increasing numbers of objectives, and the computational cost of constructing surrogate models also increases sharply. This paper proposes a composite surrogate-assisted evolutionary algorithm for expensive many-objective optimization. The crux of this method involves categorizing the surrogate models into two distinct types: a global model, constructed based on all costly real evaluations, and local models tailored to subsets derived from clustering all evaluations. Additionally, a new filling sampling criteria is proposed to guide the selection of solutions, considering the requirements of convergence, diversity, and uncertainty. Experimental results on multiple benchmark problems demonstrate that the proposed method is competitive compared to other popular surrogate-assisted evolutionary algorithms in solving expensive many-objective optimization problems within limited computational budgets.
•Composite surrogate model combines global & local models for selection.•Filling sampling criterion guides solution selection.•The proposed algorithm is competitive in solving expensive MaOPs.•Experimental results on multiple benchmark problems demonstrate the effectiveness.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The efficacy of photosensitizers in cancer phototherapy is often limited by photobleaching, low tumor selectivity, and tumor hypoxia. Assembling photosensitizers into nanostructures can improve ...photodynamic therapy efficacy and the safety profile of photosensitizers. Herein by employing supramolecular assembly, enhanced theranostic capability of Mn2+‐assisted assembly of a photosensitizer (sinoporphyrin sodium, DVDMS) is demonstrated. A tumor environment‐triggered coassembly strategy is further developed to form Mn/DVDMS nanotheranostics (nanoDVD) for cancer phototherapy. MnO2 nanosheets serve as a highly effective DVDMS carrier and in situ oxygen and nanoDVD generator. In MCF‐7 cells and xenograft tumors, MnO2/DVDMS is reduced by glutathione (GSH) and H2O2 and reassembled into nanoDVD, which can be monitored by activated magnetic resonance/fluorescence/photoacoustic signals. Intriguingly, the decrease of GSH, the production of O2, and the formation of nanoDVD are shown to be synergistic with phototherapy to improve antitumor efficacy in vitro and in vivo, offering a new avenue for cancer theranostics.
A new generation of phototheranostic agents is developed by a tumor‐environment‐triggered coassembly strategy. MnO2 nanosheets serve as a highly effective photosensitizer carrier and in situ oxygen and nanotheranostic generator, with promising properties for trimodal magnetic resonance/fluorescence/photoacoustic‐imaging‐guided phototherapy.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Tumor microenvironment-induced ultrasmall nanodrug generation (TMIUSNG) is an unprecedented approach to overcome the drug penetration barriers across complex biological systems, poor circulation ...stability and limited drug loading efficiency (DLE). Herein, a novel strategy was designed to synthesize metal–organic nanodrug complexes (MONCs) through supramolecular coassembly of photosensitizer sinoporphyrin sodium, chemotherapeutic drug doxorubicin and ferric ions. Compared with the free photosensitizer, MONCs produced 3-fold more reactive oxygen species (ROS) through the energy transfer-mediated fluorescence quenching. Remarkably, the self-delivering supramolecular MONCs with high DLE acted as a potent ultrasmall-nanodrug generator in response to the mild acidic tumor microenvironment to release ultrasmall nanodrugs (5–10 nm in diameter) from larger parental nanoparticles (140 nm in diameter), which in turn enhanced the intratumor permeability and therapeutic efficacy. The key mechanism of MONC synthesis was proposed, and we, for the first time, validated the generation of supramolecular scaffold intermediates between MONCs’ assembly/disassembly states, as well as their involvement in multidrug ligands interactions. This proof-of-concept TMIUSNG strategy provides a foundation for the rational design of analogous carrier-free nanotheranostics through the combination of multiple therapeutic agents and metal ions with imaging functions.
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IJS, KILJ, NUK, PNG, UL, UM
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