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1.
Mol Ecol ; : e17380, 2024 May 14.
Article in English | MEDLINE | ID: mdl-38745400

ABSTRACT

In order to thrive and survive, plant species need to combine stability in the long term and rapid response to environmental challenges in the short term. The former would be reflected by parallel or convergent adaptation across species, and the latter by pronounced local adaptation among populations of the same species. In the present study, we generated a high-quality genome and re-sequenced 177 individuals for Gymnocarpos przewalskii, an important desert plant species from North-West China, to detect local adaptation. We first focus on ancient adaptation to aridity at the molecular level by comparing the genomic data of 15 species that vary in their ability to withstand aridity. We found that a total of 118 genes were shared across xerophytic species but absent from non-xerophytic species. Of the 65 found in G. przewalskii, 63 were under purifying selection and two under positive selection. We then focused on local adaptation. Up to 20% of the G. przewalskii genome showed signatures of local adaptation to aridity during population divergence. Thirteen of the selected shared xerophytic genes were reused in local adaptation after population differentiation. Hence, only about 20% of the genes shared and specific to xerophytic species and associated with adaptation to aridity were later recruited for local adaptation in G. przewalskii.

2.
Phys Chem Chem Phys ; 2024 May 16.
Article in English | MEDLINE | ID: mdl-38752432

ABSTRACT

High-level ab initio calculations are conducted for studying the kinetics of three linear pentanol radicals generated through H-atom abstraction reactions. The species involved are optimized using the M06-2X/6-311++G(d,p) level of theory, while a relaxed scan at the M06-2X/6-31g level of theory with 10° increments is used for the hindrance potential for low-frequency torsional modes. Single-point energies for all stationary points are obtained through the QCISD(T) and MP2 methods in combination with cc-pVDZ, cc-pVTZ, and cc-pVQZ basis sets, which can be extrapolated to the complete basis set (CBS) limit. The rate constants and branching ratios for isomerization and decomposition reactions are computed over a temperature range of 250-2000 K and a pressure range of 0.01-100 atm. Isomerization reactions are dominant at low temperatures, while decomposition reactions are more dominant at high temperatures. The branching ratio of the isomerization reaction exhibits a slight decrease with increasing pressure, while the trend for decomposition reactions depends on the type of the breaking bond. Based on the calculations for five branched pentanol radicals in part I, kinetics of linear and branched pentanol radicals are compared in this work and the results reveal that, for the same kind of ß-scission reaction at similar positions of linear and branched pentanol radicals, the rate constants of branched ones are faster than those of linear ones at low temperatures. The hydroxyl group adjacent to the breaking bond can increase the ß-scission reaction rate constants, while the effect can be ignored when the hydroxyl group is not adjacent to the breaking bond. Moreover, compared to when the hydroxyl group is located in the middle of the carbon chain, its positioning at the chain's end yields a more noticeable impact on the products and rate constants of C-O bond and O-H bond ß-scission reactions. Besides, when incorporating calculated rate constants into the CRECK model, the updated mechanism shows a better performance for ignition delay times of 1-pentanol in the NTC range but exhibits lower reactivity at higher temperatures. The simulation of speciation profiles also shows better agreement with the experimental data obtained using a flow reactor.

3.
Small ; : e2402219, 2024 Apr 18.
Article in English | MEDLINE | ID: mdl-38634337

ABSTRACT

In this work, an intramolecular carbon nitride (CN)-based quaternary homojunction functionalized with pyridine rings is prepared via an in situ alkali-assisted copolymerization strategy of bulk CN and 2-aminopyridine for efficient visible light hydrogen generation. In the obtained structure, triazine-based CN (TCN), heptazine-based CN (HCN), pyridine unit incorporated TCN, and pyridine ring inserted HCN constitute a special multicomponent system and form a built-in electric field between the crystalline semiconductors by the arrangement of energy band levels. The electron-withdrawing function of the conjugated heterocycle can trigger the skeleton delocalization and edge induction effect. Highly accelerated photoelectron-hole transfer rates via multi-stepwise charge migration pathways are achieved by the synergistic effect of the functional group modification and molecular quaternary homojunction. Under the addition of 5 mg 2-aminopyridine, the resulting homojunction framework exhibits a significantly improved hydrogen evolution rate of 6.64 mmol g-1 h-1 with an apparent quantum efficiency of 12.27% at 420 nm. Further, the catalyst verifies its potential commercial value since it can produce hydrogen from various real water environments. This study provides a reliable way for the rational design and fabrication of intramolecular multi-homojunction to obtain high-efficient photocatalytic reactions.

4.
Nano Lett ; 24(14): 4165-4171, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38534019

ABSTRACT

An electrical-controllable antiferromagnet tunnel junction is a key goal in spintronics, holding immense promise for ultradense and ultrastable antiferromagnetic memory with high processing speed for modern information technology. Here, we have advanced toward this goal by achieving an electrical-controllable antiferromagnet-based tunnel junction of Pt/Co/Pt/Co/IrMn/MgO/Pt. The exchange coupling between antiferromagnetic IrMn and Co/Pt perpendicular magnetic multilayers results in the formation of an interfacial exchange bias and exchange spring in IrMn. Encoding information states "0" and "1" is realized through the exchange spring in IrMn, which can be electrically written by spin-orbit torque switching with high cyclability and electrically read by antiferromagnetic tunneling anisotropic magnetoresistance. Combining spin-orbit torque switching of both exchange spring and exchange bias, a 16 Boolean logic operation is successfully demonstrated. With both memory and logic functionalities integrated into our electrically controllable antiferromagnetic-based tunnel junction, we chart the course toward high-performance antiferromagnetic logic-in-memory.

5.
Chem Commun (Camb) ; 60(24): 3217-3225, 2024 Mar 19.
Article in English | MEDLINE | ID: mdl-38436212

ABSTRACT

High-throughput continuous flow technology has emerged as a revolutionary approach in chemical synthesis, offering accelerated experimentation and improved efficiency. With the aid of process analytical technology and automation, this system not only enables rapid optimisation of reaction conditions at the millimole to the picomole scale, but also facilitates automated scale-up synthesis. It can even achieve the self-planning and self-synthesis of small drug molecules with artificial intelligence incorporated in the system. The versatility of the system is highlighted by its compatibility with both electrochemistry and photochemistry, and its significant applications in organic synthesis and drug discovery. This highlight summarises its recent developments and applications, emphasising its significant impact on advancing research across multiple disciplines.

6.
ACS Sustain Chem Eng ; 12(8): 3243-3255, 2024 Feb 26.
Article in English | MEDLINE | ID: mdl-38425833

ABSTRACT

Plastics' long degradation time and their role in adding millions of metric tons of plastic waste to our oceans annually present an acute environmental challenge. Handling end-of-life waste from wind turbine blades (WTBs) is equally pressing. Currently, WTB waste often finds its way into landfills, emphasizing the need for recycling and sustainable solutions. Mechanical recycling of composite WTB presents an avenue for the recovery of glass fibers (GF) for repurposing as fillers or reinforcements. The resulting composite materials exhibit improved properties compared to the pure PAN polymer. Through the employment of the dry-jet wet spinning technique, we have successfully manufactured PAN/GF coaxial-layered fibers with a 0.1 wt % GF content in the middle layer. These fibers demonstrate enhanced mechanical properties and a lightweight nature. Most notably, the composite fiber demonstrates a significant 24.4% increase in strength and a 17.7% increase in modulus. These fibers hold vast potential for various industrial applications, particularly in the production of structural components (e.g., electric vehicles), contributing to enhanced performance and energy efficiency.

7.
Curr Issues Mol Biol ; 46(2): 1047-1063, 2024 Jan 23.
Article in English | MEDLINE | ID: mdl-38392184

ABSTRACT

Due to the extensive genetic and antigenic variation in Porcine Reproductive and Respiratory Syndrome Virus (PRRSV), as well as its rapid mutability and evolution, PRRS prevention and control can be challenging. An expeditious and sensitive neutralization assay for PRRSV is presented to monitor neutralizing antibodies (NAbs) in serum during vaccine research. Here, a PRRSV expressing eGFP was successfully rescued with reverse genetics based on the infectious clone HuN4-F112-eGFP which we constructed. The fluorescent protein expressions of the reporter viruses remained stable for at least five passages. Based on this reporter virus, the neutralization assay can be easily used to evaluate the level of NAbs by counting cells with green fluorescence. Compared with the classical CPE assay, the newly developed assay increases sensitivity by one- to four-fold at the early antibody response stage, thus saving 2 days of assay waiting time. By using this assay to unveil the dynamics of neutralizing antibodies against PRRSV, priming immunity through either a single virulent challenge or only vaccination could produce limited NAbs, but re-infection with PRRSV would induce a faster and stronger NAb response. Overall, the novel HuN4-F112-eGFP-based neutralization assay holds the potential to provide a highly efficient platform for evaluating the next generation of PRRS vaccines.

8.
Small ; 20(6): e2306394, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37775949

ABSTRACT

Nanoparticles form long-range micropatterns via self-assembly or directed self-assembly with superior mechanical, electrical, optical, magnetic, chemical, and other functional properties for broad applications, such as structural supports, thermal exchangers, optoelectronics, microelectronics, and robotics. The precisely defined particle assembly at the nanoscale with simultaneously scalable patterning at the microscale is indispensable for enabling functionality and improving the performance of devices. This article provides a comprehensive review of nanoparticle assembly formed primarily via the balance of forces at the nanoscale (e.g., van der Waals, colloidal, capillary, convection, and chemical forces) and nanoparticle-template interactions (e.g., physical confinement, chemical functionalization, additive layer-upon-layer). The review commences with a general overview of nanoparticle self-assembly, with the state-of-the-art literature review and motivation. It subsequently reviews the recent progress in nanoparticle assembly without the presence of surface templates. Manufacturing techniques for surface template fabrication and their influence on nanoparticle assembly efficiency and effectiveness are then explored. The primary focus is the spatial organization and orientational preference of nanoparticles on non-templated and pre-templated surfaces in a controlled manner. Moreover, the article discusses broad applications of micropatterned surfaces, encompassing various fields. Finally, the review concludes with a summary of manufacturing methods, their limitations, and future trends in nanoparticle assembly.

9.
Small ; 20(2): e2305481, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37658518

ABSTRACT

This work reports a dual heterojunction of etched MIL-68(In)-NH2 (MN) supported heptazine-/triazine-based carbon nitride (HTCN) via a facile hydrothermal process for photocatalytic ammonia (NH3 ) synthesis. By applying the hydrothermal treatment, MN microrods are chemically etched into hollow microtubes, and HTCN with nanorod array structures are simultaneously tightly anchored on the outside surface of the microtubes. With the addition of 9 wt% HTCN, the resulting dual heterojunction presents an enhanced photocatalytic ammonia yield rate of 5.57 mm gcat -1 h-1 with an apparent quantum efficiency of 10.89% at 420 nm. Moreover, stable ammonia generation using seawater, tap water, lake water, and turbid water in the absence of sacrificial reagents verifies the potential of the dual-heterojunction composites as a commercially viable photosystem. The obtained one-dimensional (1D) microtubes and coating of HTCN confers this unique composite with extended visible-light harvesting and accelerated charge carrier migration via a multi-stepwise charge transfer pathway. This work provides a new strategy for optimizing nitrogen (N2 )-into-ammonia conversion efficiency by designing novel dual-heterojunction catalysts.

10.
Mol Biotechnol ; 2023 Nov 02.
Article in English | MEDLINE | ID: mdl-37919618

ABSTRACT

Deep hypothermic circulatory arrest (DHCA) can protect the brain during cardiac and aortic surgery by cooling the body, but meanwhile, temporary or permanent brain injury may arise. H2S protects neurons and the central nervous system, especially from secondary neuronal injury. We aim to unveil part of the mechanism of H2S's attenuating effect on brain injury induced by DHCA by exploring crucial target genes, and further promote the clinical application of H2S in DHCA. Nine SD rats were utilized to provide histological and microarray samples, and further the differential expression analysis. Then we conducted GO and KEGG pathway enrichment analyses on candidate genes. The protein-protein interaction (PPI) networks were performed by STRING and GeneMANIA. Crucial target genes' expression was validated by qRT-PCR and western blot. Histological study proved DHCA's damaging effect and H2S's repairing effect on brain. Next, we got 477 candidate genes by analyzing differentially expressed genes. The candidate genes were enriched in 303 GO terms and 28 KEGG pathways. Then nine genes were selected as crucial target genes. The function prediction by GeneMANIA suggested their close relation to immunity. FGF2 was identified as the crucial gene. FGF2 plays a vital role in the pathway when H2S attenuates brain injury after DHCA. Our research provides more information for understanding the mechanism of H2S attenuating brain injury after DHCA. We infer the process might probably be closely associated with immunity.

11.
Metabolites ; 13(10)2023 Oct 17.
Article in English | MEDLINE | ID: mdl-37887411

ABSTRACT

Growing evidence indicates that metabolites and energy metabolism play an active rather than consequential role in regulating cellular fate. Cardiac development requires dramatic metabolic remodeling from relying primarily on glycolysis in pluripotent stem cells (PSCs) to oxidizing a wide array of energy substrates to match the high bioenergetic demands of continuous contraction in the developed heart. However, a detailed analysis of how remodeling of energy metabolism contributes to human cardiac development is lacking. Using dynamic multiple reaction monitoring metabolomics of central carbon metabolism, we evaluated temporal changes in energy metabolism during human PSC 3D cardiac lineage specification. Significant metabolic remodeling occurs during the complete differentiation, yet temporal analysis revealed that most changes occur during transitions from pluripotency to mesoderm (day 1) and mesoderm to early cardiac (day 5), with limited maturation of cardiac metabolism beyond day 5. Real-time metabolic analysis demonstrated that while hPSC cardiomyocytes (hPSC-CM) showed elevated rates of oxidative metabolism compared to PSCs, they still retained high glycolytic rates, confirming an immature metabolic phenotype. These observations support the opportunity to metabolically optimize the differentiation process to support lineage specification and maturation of hPSC-CMs.

12.
Sci Total Environ ; 900: 166752, 2023 Nov 20.
Article in English | MEDLINE | ID: mdl-37659572

ABSTRACT

Anaerobic oxidation of methane coupled to nitrous oxide reduction (N2O-AOM) is an important microbial pathway for mitigating greenhouse gases. However, it remains largely unknown whether this process could occur in landfills, which are important anthropogenic sources of greenhouse gases emissions. Here, 13CH4 was supplied in microcosm incubations to track potential rates for the N2O-AOM process in landfill cover soils (LCS). The highest rates for the N2O-AOM process were observed in the bottom layers of LCS and it could be remarkably promoted by the addition of electron shuttles. In addition, 2-bromoethanesulfonic sodium inhibited the N2O-AOM process and reduced the expression of the mcrA gene, showing that ANME archaea/methanogens might be the methane oxidizers for the N2O-AOM process. Our results implied that the N2O-AOM process was an overlooked process for synchronous control of methane and nitrous oxide and may contribute to the future management of greenhouse gases emissions from landfills.


Subject(s)
Greenhouse Gases , Anaerobiosis , Nitrous Oxide , Methane , Soil
13.
Small ; 19(50): e2302718, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37501325

ABSTRACT

Lithium-ion batteries (LIBs) have significantly impacted the daily lives, finding broad applications in various industries such as consumer electronics, electric vehicles, medical devices, aerospace, and power tools. However, they still face issues (i.e., safety due to dendrite propagation, manufacturing cost, random porosities, and basic & planar geometries) that hinder their widespread applications as the demand for LIBs rapidly increases in all sectors due to their high energy and power density values compared to other batteries. Additive manufacturing (AM) is a promising technique for creating precise and programmable structures in energy storage devices. This review first summarizes light, filament, powder, and jetting-based 3D printing methods with the status on current trends and limitations for each AM technology. The paper also delves into 3D printing-enabled electrodes (both anodes and cathodes) and solid-state electrolytes for LIBs, emphasizing the current state-of-the-art materials, manufacturing methods, and properties/performance. Additionally, the current challenges in the AM for electrochemical energy storage (EES) applications, including limited materials, low processing precision, codesign/comanufacturing concepts for complete battery printing, machine learning (ML)/artificial intelligence (AI) for processing optimization and data analysis, environmental risks, and the potential of 4D printing in advanced battery applications, are also presented.

14.
Phys Chem Chem Phys ; 25(26): 17320-17336, 2023 Jul 05.
Article in English | MEDLINE | ID: mdl-37345723

ABSTRACT

Theoretical investigations on the kinetics of decomposition and isomerization reactions for five types of branched pentanol radicals are carried out in this work. The M06-2X/6-311++G(d,p) level of theory was used to optimize the geometries of all reactants, transition states, and products, while the hindrance potentials for the lower frequency modes in all of the species were obtained through a relaxed scan with an increment of 10° at the M06-2X/6-31G level of theory. Single-point energies of all species were determined at the QCISD(T)/cc-pVDZ, TZ level of theories with basis set corrections from MP2/cc-pVDZ, TZ, QZ methods. The RRKM/master equation was solved to calculate the pressure- and temperature-dependent rate coefficients for all channels in the pressure range of 0.01-100 atm over 250-2000 K. Pressure and temperature-dependent branching fractions of key species produced from pentanol radicals show that most of the pentanol radical isomers tend to isomerize to alkoxy radicals via a six-membered-ring or five-membered-ring transition state at low temperatures, producing ketones or aldehydes. At higher temperatures, the ß-scission reactions are the main reaction channels for the consumption of pentanol radicals. A weak pressure dependence has been found for all isomerization reactions, and it becomes more and more important as pressure increases. The pressure dependence trends are different for the ß-scission reactions of different branched pentanol radicals. In part I, the results for branched pentanol radical isomers are presented in detail, while in part II the results for linear pentanol radical isomers will be discussed.

15.
Microbiol Spectr ; : e0451922, 2023 Mar 28.
Article in English | MEDLINE | ID: mdl-36975825

ABSTRACT

Infections caused by multidrug-resistant bacteria are becoming increasingly serious. The aminoglycoside antibiotics have been widely used to treat severe Gram-negative bacterial infections. Here, we reported that a class of small molecules, namely, halogenated indoles, can resensitize Pseudomonas aeruginosa PAO1 to aminoglycoside antibiotics such as gentamicin, kanamycin, tobramycin, amikacin, neomycin, ribosomalin sulfate, and cisomicin. We selected 4F-indole as a representative of halogenated indoles to investigate its mechanism and found that the two-component system (TCS) PmrA/PmrB inhibited the expression of multidrug efflux pump MexXY-OprM, allowing kanamycin to act intracellularly. Moreover, 4F-indole inhibited the biosynthesis of several virulence factors, such as pyocyanin, type III secretion system (T3SS), and type VI secretion system (T6SS) exported effectors, and reduced the swimming and twitching motility by suppressing the expression of flagella and type IV pili. This study suggests that the combination of 4F-indole and kanamycin can be more effective against P. aeruginosa PAO1 and affect its multiple physiological activities, providing a novel insight into the reactivation of aminoglycoside antibiotics. IMPORTANCE Infections caused by Pseudomonas aeruginosa have become a major public health crisis. Its resistance to existing antibiotics causes clinical infections that are hard to cure. In this study, we found that halogenated indoles in combination with aminoglycoside antibiotics could be more effective than antibiotics alone against P. aeruginosa PAO1 and preliminarily revealed the mechanism of the 4F-indole-induced regulatory effect. Moreover, the regulatory effect of 4F-indole on different physiological behaviors of P. aeruginosa PAO1 was analyzed by combined transcriptomics and metabolomics. We explain that 4F-indole has potential as a novel antibiotic adjuvant, thus slowing down the further development of bacterial resistance.

16.
J Clin Med ; 12(3)2023 Jan 19.
Article in English | MEDLINE | ID: mdl-36769462

ABSTRACT

Neurological dysfunction is a common complication of deep hypothermic circulatory arrest (DHCA). Endoplasmic reticulum (ER) stress plays a role in neuronal ischemia-reperfusion injury; however, it is unknown whether it contributes to DHCA-induced brain injury. Here, we aimed to investigate the role of ER stress in a rat DHCA model and cell hypothermic oxygen-glucose deprivation reoxygenation (OGD/R) model. ER stress and apoptosis-related protein expression were identified using Western blot analysis. Cell counting assay-8 and flow cytometry were used to determine cell viability and apoptosis, respectively. Brain injury was evaluated using modified neurological severity scores, whereas brain injury markers were detected through histological examinations and immunoassays. We observed significant ER stress molecule upregulation in the DHCA rat hippocampus and in hypothermic OGD/R PC-12 cells. In vivo and in vitro experiments showed that ER stress or activating transcription factor 6 (ATF6) inhibition alleviated rat DHCA-induced brain injury, increased cell viability, and decreased apoptosis accompanied by C/EBP homologous protein (CHOP). ER stress is involved in DHCA-induced brain injury, and the inhibition of the ATF6 branch of ER stress may ameliorate this injury by inhibiting CHOP-mediated apoptosis. This study establishes a scientific foundation for identifying new therapeutic targets for perioperative brain protection in clinical DHCA.

17.
Trends Microbiol ; 31(7): 749-762, 2023 07.
Article in English | MEDLINE | ID: mdl-36849330

ABSTRACT

QseB/QseC is a two-component system that is involved in the regulation of multiple bacterial behaviors by regulating quorum sensing, bacterial pathogenicity, and antibiotic resistance. Thus, QseB/QseC could provide a target for new antibiotic development. Recently, QseB/QseC has been found to confer survival advantages to environmental bacteria under stress conditions. The molecular mechanistic understanding of QseB/QseC has become an active area of research and revealed some emerging themes, including a deeper understanding of QseB/QseC regulation in different pathogens and environmental bacteria, the functional difference of QseB/QseC among species, and the possibility of analyzing QseB/QseC evolution. Here, we discuss the progression of QseB/QseC studies and describe several unresolved issues and future directions. Resolving these issues is among the challenges of future QseB/QseC studies.


Subject(s)
Bacterial Proteins , Escherichia coli Proteins , Bacterial Proteins/metabolism , Escherichia coli/metabolism , Bacteria/genetics , Bacteria/metabolism , Quorum Sensing/genetics , Virulence , Gene Expression Regulation, Bacterial , Escherichia coli Proteins/metabolism
18.
Angew Chem Int Ed Engl ; 62(16): e202301262, 2023 Apr 11.
Article in English | MEDLINE | ID: mdl-36812298

ABSTRACT

TFA promoted deprotection of O-Ts activated N-Boc hydroxylamines triggers aminofunctionalization-based polycyclizations of tethered alkenes. The processes involve intramolecular stereospecific aza-Prilezhaev alkene aziridination in advance of stereospecific C-N cleavage by a pendant nucleophile. Using this approach, a wide range of fully intramolecular alkene anti-1,2-difunctionalizations can be achieved, including diaminations, amino-oxygenations and amino-arylations. Trends associated with the regioselectivity of the C-N cleavage step are outlined. The method provides a broad and predictable platform for accessing diverse C(sp3 )-rich polyheterocycles of relevance to medicinal chemistry.

19.
ChemSusChem ; 16(8): e202202059, 2023 Apr 21.
Article in English | MEDLINE | ID: mdl-36647204

ABSTRACT

Porous triazine-/heptazine-based carbon nitride (THCN) homojunction with chloride (Cl) doping was synthesized by a simple, one-step photochemical synthesis route for efficient visible-light-driven overall water splitting. The phase ratio of triazine-based carbon nitride (TCN) and heptazine-based carbon nitride (HCN), texture and morphology of the THCN isotype junction were finely tuned by varying ultraviolet irradiation time and washing solvents. After washing with acetonitrile, the resulting porous THCN nanosheets with 48 h irradiation contain 21 wt % TCN and 79 wt % HCN units and reveal a significantly improved photocatalytic performance with H2 and O2 production rates up to 7.9 and 4.2 µmol h-1 , respectively, about 3.8 times higher than that of THCN prepared by 36 h illumination. The dual-phase interaction, holey structure, and Cl dopants favor the exposure of active sites, extended visible-light harvesting, accelerated charge transfer, and enhanced photoreduction ability, thereby improving photocatalytic activity.

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