Elucidating the structural and conformational preferences of bioactive chromone and its monohydrate through advanced rotational spectroscopy.

Chromones are a class of naturally occurring compounds, renowned for their diverse biological activities with significant relevance in medicine and biochemistry. This study marks the first analysis of rotational spectra of both the chromone monomer and its monohydrate through Fourier transform microwave spectroscopy. The observation of nine mono-substituted 13C isotopologues facilitated a semi-experimental determination of the equilibrium structure of the chromone monomer. In the case of chromone monohydrate, two distinct isomers were identified, each characterized by a combination of O-H⋯O and C-H⋯O hydrogen bonds involving the chromone's carbonyl group. This study further delved into intermolecular non-covalent interactions, employing different theoretical approaches. The relative population ratio of the two identified isomers was estimated to be about 2:1 within the supersonic jet.

Fluorination effects on non-covalent binding forces: A rotational study on the 2-(trifluoromethyl)acrylic acid-water complex.

This study explores the effects of the -CF3 group on non-covalent interactions through a comprehensive rotational investigation of the 2-(trifluoromethyl)acrylic acid-water complex. Employing Fourier transform microwave spectroscopy complemented by quantum chemical calculations, two isomers, i.e., s-cis and s-trans structures, have been observed in the pulsed jet. Based on relative intensity measurements, the s-cis to the s-trans population ratio was experimentally estimated to be âˆ¼ 1:1.2. Subsequently, a comparison of the non-covalent interactions was carried out between the three similar complexes, acrylic acid-water, methacrylic acid-water, and 2-(trifluoromethyl)acrylic acid-water, offering quantitative insights into fluorination affecting the strength of the formed hydrogen bonds important, e.g., in molecular recognition.

Blood glucose fluctuation and in-hospital mortality among patients with acute myocardial infarction: eICU collaborative research database.

BACKGROUND: To assess the relationship between glycemic variability, glucose fluctuation trajectory and the risk of in-hospital mortality in patients with acute myocardial infarction (AMI). METHODS: This retrospective cohort study included AMI patients from eICU Collaborative Research Database. In-hospital mortality of AMI patients was primary endpoint. Blood glucose levels at admission, glycemic variability, and glucose fluctuation trajectory were three main study variables. Blood glucose levels at admission were stratified into: normal, intermediate, and high. Glycemic variability was evaluated using the coefficient of variation (CV), divided into four groups based on quartiles: quartile 1: CV≤10; quartile 2: 1030. Univariate and multivariate Cox regression models to assess the relationship between blood glucose levels at admission, glycemic variability, glucose fluctuation trajectory, and in-hospital mortality in patients with AMI. RESULTS: 2590 participants were eventually included in this study. There was a positive relationship between high blood glucose level at admission and in-hospital mortality [hazard ratio (HR) = 1.42, 95%confidence interval (CI): 1.06-1.89]. The fourth quartile (CV>30) of CV was associated with increased in-hospital mortality (HR = 2.06, 95% CI: 1.25-3.40). The findings indicated that only AMI individuals in the fourth quartile of glycemic variability, exhibited an elevated in-hospital mortality among those with normal blood glucose levels at admission (HR = 2.33, 95% CI: 1.11-4.87). Additionally, elevated blood glucose level was a risk factor for in-hospital mortality in AMI patients. CONCLUSION: Glycemic variability was correlated with in-hospital mortality, particularly among AMI patients who had normal blood glucose levels at admission. Our study findings also suggest early intervention should be implemented to normalize high blood glucose levels at admission of AMI.

Heavy Metal-Induced Assembly of DNA Network Biosensor from Double-Loop Hairpin Probes for Ultrasensitive Detection of UO22+ in Water and Soil Samples.

The uranyl ion (UO22+) is the most stable form of uranium, which exhibits high toxicity and bioavailability posing a severe risk to human health. The construction of ultrasensitive, reliable, and robust sensing techniques for UO22+ detection in water and soil samples remains a challenge. Herein, a DNA network biosensor was fabricated for UO22+ detection using DNAzyme as the heavy metal recognition element and double-loop hairpin probes as DNA assembly materials. UO22+-activated specific cleavage of the DNAzyme will liberate the triggered DNA fragment, which can be utilized to launch a double-loop hairpin probe assembly among Hab, Hbc, and Hca. Through multiple cyclic cross-hybridization reactions, hexagonal DNA duplex nanostructures (n[Hab•Hbc•Hca]) were formed. This DNA network sensing system generates a high fluorescence response for UO22+ monitoring. The biosensor is ultrasensitive, with a detection limit of 2 pM. This sensing system also displays an excellent selectivity and robustness, enabling the DNA network biosensor to work even in complex water and soil samples with excellent accuracy and reliability. With the advantages of enzyme-free operation, outstanding specificity, and high sensitivity, our proposed DNA network biosensor provides a reliable, simple, and robust method for trace levels of UO22+ detection in environmental samples.

Preparation and Characterization of Chloroprene Latexes Modified with Vinyl-POSS.

Water-based chloroprene latex is a solvent-free, environmentally friendly adhesive. Currently, its market demand is growing rapidly. However, there are problems such as a lack of heat resistance and poor mechanical properties, which limit its application. The introduction of vinyl-POSS (OVS) into the resin structure can effectively improve the thermal stability of chloroprene adhesives. In this paper, modified waterborne chloroprene latex was prepared by copolymerization of methyl methacrylate and OVS with chloroprene latex. The results showed that vinyl-POSS was successfully grafted onto the main chain of the waterborne chloroprene latex, and the modified waterborne chloroprene latex had good storage stability. With the increase in vinyl-POSS, the tensile strength of the chloroprene latex firstly increased and then decreased, the tensile property (peel strength of 20.2 kgf) was maintained well at a high temperature (100 °C), and the thermal stability of the chloroprene latex was improved. When the addition amount was 4%, the comprehensive mechanical properties were their best. This study provides a new idea for the construction of a new and efficient waterborne chloroprene latex system and provides more fields for the practical application of waterborne chloroprene latex. This newly developed vinyl-POSS modified chloroprene latex has great application potential for use in home furniture, bags, and seat cushions.

Intelligent monitoring of the available lead (Pb) and cadmium (Cd) in soil samples based on half adder and half subtractor molecular logic gates.

The available heavy metals in soil samples can cause the direct toxicity on ecosystems, plants, and human health. Traditional chemical extraction and recombinant bacterial methods for the available heavy metals assay often suffer from inaccuracy and poor specificity. In this work, we construct half adder and half subtractor molecular logic gates with molecular-level biocomputation capabilities for the intelligent sensing of the available lead (Pb) and cadmium (Cd). The available Pb and Cd can cleave DNAzyme sequences to release the trigger DNA, which can activate the hairpin probe assembly in the logic system. This multifunctional logic system can not only achieve the intelligent recognition of the available Pb and Cd according to the truth tables, but also can realize the simultaneous quantification with high sensitivity, with the detection limits of 2.8 pM and 25.6 pM, respectively. The logic biosensor is robust and has been applied to determination of the available Pb and Cd in soil samples with good accuracy and reliability. The relative error (Re) between the logic biosensor and the DTPA + ICP-MS method was from -8.1 % to 7.9 %. With the advantages of programmability, scalability, and multicomputing capacity, the molecular logic system can provide a simple, rapid, and smart method for intelligent monitoring of the available Pb and Cd in environmental samples.

The role of AMPK in macrophage metabolism, function and polarisation.

AMP-activated protein kinase (AMPK) is a ubiquitous sensor of energy and nutritional status in eukaryotic cells. It plays a key role in regulating cellular energy homeostasis and multiple aspects of cell metabolism. During macrophage polarisation, AMPK not only guides the metabolic programming of macrophages, but also counter-regulates the inflammatory function of macrophages and promotes their polarisation toward the anti-inflammatory phenotype. AMPK is located at the intersection of macrophage metabolism and inflammation. The metabolic characteristics of macrophages are closely related to immune-related diseases, infectious diseases, cancer progression and immunotherapy. This review discusses the structure of AMPK and its role in the metabolism, function and polarisation of macrophages. In addition, it summarises the important role of the AMPK pathway and AMPK activators in the development of macrophage-related diseases.

Efficient Treatment of Pulpitis via Transplantation of Human Pluripotent Stem Cell-Derived Pericytes Partially through LTBP1-Mediated T Cell Suppression.

Dental pulp pericytes are reported to have the capacity to generate odontoblasts and express multiple cytokines and chemokines that regulate the local immune microenvironment, thus participating in the repair of dental pulp injury in vivo. However, it has not yet been reported whether the transplantation of exogenous pericytes can effectively treat pulpitis, and the underlying molecular mechanism remains unknown. In this study, using a lineage-tracing mouse model, we showed that most dental pulp pericytes are derived from cranial neural crest. Then, we demonstrated that the ablation of pericytes could induce a pulpitis-like phenotype in uninfected dental pulp in mice, and we showed that the significant loss of pericytes occurs during pupal inflammation, implying that the transplantation of pericytes may help to restore dental pulp homeostasis during pulpitis. Subsequently, we successfully generated pericytes with immunomodulatory activity from human pluripotent stem cells through the intermediate stage of the cranial neural crest with a high level of efficiency. Most strikingly, for the first time we showed that, compared with the untreated pulpitis group, the transplantation of hPSC-derived pericytes could substantially inhibit vascular permeability (the extravascular deposition of fibrinogen, ** p < 0.01), alleviate pulpal inflammation (TCR+ cell infiltration, * p < 0.05), and promote the regeneration of dentin (** p < 0.01) in the mouse model of pulpitis. In addition, we discovered that the knockdown of latent transforming growth factor beta binding protein 1 (LTBP1) remarkably suppressed the immunoregulation ability of pericytes in vitro and compromised their in vivo regenerative potential in pulpitis. These results indicate that the transplantation of pericytes could efficiently rescue the aberrant phenotype of pulpal inflammation, which may be partially due to LTBP1-mediated T cell suppression.

Low-Valent-Tungsten-Catalyzed Aerobic Oxidative Cross-Dehydrogenative Coupling Reaction.

A straightforward and convenient protocol was established for the synthesis of thiophosphates and 3-sulfenylated indoles via low-valent-tungsten-catalyzed aerobic oxidative cross-dehydrogenative coupling reactions. These reactions occur under mild conditions and simple operations with commercially available starting materials, processing the advantage of excellent atom and step economy, broad substrate scope, and good functional groups tolerance. Moreover, this transformation could be practiced on the gram scale, which exhibits great potential in the preparation of drug-derived or bioactive molecules.

Evolution of China's interaction with Middle Eastern countries under the Belt and Road Initiative.

The Middle East holds a critical strategic position in global politics, economy, and military affairs, serving as a pivotal hub for the advancement of the Belt and Road Initiative (BRI) through both land and sea routes. Since the proposal of BRI, China's cooperation with Middle Eastern countries has steadily deepened. Consequently, examining the evolution of China's interaction with Middle Eastern nations over the past decade is of paramount significance for future development. This study utilizes the GDELT database to construct formulas for measuring event impact and bilateral relationship intensity. It analyzes the temporal development and spatial patterns of China's interaction with Middle Eastern countries while also examining the types of interactive relationships between China and individual countries in the Middle East under the principle of reciprocity. The findings indicate that the overall interaction between China and Middle Eastern countries remains stable. Cooperative relationships have transitioned from a "single cooperation" approach to a "dual cooperation" model involving Iran and Saudi Arabia. Moreover, the development trajectory has shifted from an imbalanced "north-high, south-low" pattern towards equilibrium, resulting in a general decline in conflict relations and a decrease in inter-country disparities. The prevalent type of interaction between countries is characterized by balance.

The heat response regulators HSFA1s promote Arabidopsis thermomorphogenesis via stabilizing PIF4 during the day.

During summer, plants often experience increased light inputs and high temperatures, two major environmental factors with contrasting effects on thermomorphological traits. The integration of light and temperature signaling to control thermomorphogenesis in plants is critical for their acclimation in such conditions, but the underlying mechanisms remain largely unclear. We found that heat shock transcription factor 1d (HSFA1d) and its homologs are necessary for plant thermomorphogenesis during the day. In response to warm daytime temperature, HSFA1s markedly accumulate and move into the nucleus where they interact with phytochrome-interacting factor 4 (PIF4) and stabilize PIF4 by interfering with phytochrome B-PIF4 interaction. Moreover, we found that the HSFA1d nuclear localization under warm daytime temperature is mediated by constitutive photomorphogenic 1-repressed GSK3-like kinase BIN2. These results support a regulatory mechanism for thermomorphogenesis in the daytime mediated by the HSFA1s-PIF4 module and uncover HSFA1s as critical regulators integrating light and temperature signaling for a better acclimation of plants to the summer high temperature.

n → π* Interaction Enabling Transient Inversion of Chirality.

This study reports the observation and characterization of two isomers of the acrolein dimer by using high-resolution rotational spectroscopy in pulsed jets. The first isomer is stabilized by two hydrogen bonds, adopting a planar configuration, and is energetically favored over the second isomer, which exhibits a dominant n → π* interaction in a nearly orthogonal arrangement. Surprisingly, the n → π* interaction was revealed to enable a concerted tunneling motion of two moieties along the carbonyl group. This motion leads to the inversion of transient chirality associated with the exchange of donor-acceptor roles, as revealed by the spectral feature of quadruplets. Inversion of transient chirality is a fundamental phenomenon in quantum mechanics and commonly observed for only inversional motions of protons. It is the first discovery, to the best of our knowledge, that such heavy moieties can also undergo chirality inversion.

Aqueous Cationic Fluorinated Polyurethane for Application in Novel UV-Curable Cathodic Electrodeposition Coatings.

Aqueous polyurethane is an environmentally friendly, low-cost, high-performance resin with good abrasion resistance and strong adhesion. Cationic aqueous polyurethane is limited in cathodic electrophoretic coatings due to its complicated preparation process and its poor stability and single performance after emulsification and dispersion. The introduction of perfluoropolyether alcohol (PFPE-OH) and light curing technology can effectively improve the stability of aqueous polyurethane emulsions, and thus enhance the functionality of coating films. In this paper, a new UV-curable fluorinated polyurethane-based cathodic electrophoretic coating was prepared using cationic polyurethane as a precursor, introducing PFPE-OH capping, and grafting hydroxyethyl methacrylate (HEMA). The results showed that the presence of perfluoropolyether alcohol in the structure affected the variation of the moisture content of the paint film after flash evaporation. Based on the emulsion particle size and morphology tests, it can be assumed that the fluorinated cationic polyurethane emulsion is a core-shell structure with hydrophobic ends encapsulated in the polymer and hydrophilic ends on the outer surface. After abrasion testing and baking, the fluorine atoms of the coating were found to increase from 8.89% to 27.34%. The static contact angle of the coating to water was 104.6 ± 3°, and the water droplets rolled off without traces, indicating that the coating is hydrophobic. The coating has excellent thermal stability and tensile properties. The coating also passed the tests of impact resistance, flexibility, adhesion, and resistance to chemical corrosion in extreme environments. This study provides a new idea for the construction of a new and efficient cathodic electrophoretic coating system, and also provides more areas for the promotion of cationic polyurethane to practical applications.

Fluorination effects probed in 4-fluoroacetophenone and its monohydrate.

Rotational spectra of the 4-fluoroacetophenone monomer and its monohydrate were investigated by Fourier transform microwave spectroscopy complemented with quantum chemical calculations. One conformer of 4-fluoroacetophenone and two isomers of 4-fluoroacetophenone-H2O have been observed in the pulsed jets. The observation of all mono-substituted 13C isotopologues in natural abundance allows an accurate structural determination of the 4-fluoroacetophenone monomer. Both detected isomers of 4-fluoroacetophenone-H2O are stabilized by a dominant O-H⋯O and a secondary C-H⋯O hydrogen bond. The fluorination effects on the geometries, intermolecular non-covalent interactions and V3 barrier of the methyl internal rotation were analysed. The relative population ratio of the two observed isomers for 4-fluoroacetophenone-H2O was also estimated to be NI/NII ≈ 7/1.

Fluorescence biosensor for ultrasensitive detection of the available lead based on target biorecognition-induced DNA cyclic assembly.

A fluorescence biosensor was developed for the ultrasensitive detection of the available lead in soil samples by coupling with DNAzyme and hairpin DNA cyclic assembly. The biorecognition between lead and 8-17 DNAzyme will cleave the substrate strands (DNA2) and release the trigger DNA (T), which can be used to initiate the DNA assembly reactions among the hairpins (H1, H2, and H3). The formed Y-shaped sensing scaffold (H1-H2-H3) contains active Mg2+-DNAyzmes at three directions. In the presence of Mg2+, the BHQ and FAM modified H4 will be cleaved by the Mg2+-DNAyzme to generate a high fluorescence signal for lead monitoring. The linear range of the fluorescence biosensor is from 1 pM to 100 nM and the detection limit is 0.2 pM. The biosensor also exhibited high selectivity and the nontarget competing heavy metals did not interfere with the detection results. Compare with the traditional method (DTPA+ICP-MS) for the available lead detection, the relative error (Re) is in the range from -8.3 % to 9.5 %. The results indicated that our constructed fluorescence biosensor is robust, accurate, and reliable, and can be applied directly to the detection of the available lead in soil samples without complex extraction steps.

Laboratory Rotational Spectrum and Radio-Astronomical Search of Acetoin.

The rotational spectrum of acetoin (3-hydroxy-2-butanone) was measured by using Fourier transform microwave spectroscopy with the aid of quantum chemical calculations. Only one conformer of acetoin was detected in the pulsed jet, whose spectrum featured the splittings raised from the internal rotation of the methyl top linking to the C═O group. Based on the spectroscopic result, radio-astronomical searches for acetoin were carried out toward the massive star-forming region Sgr B2(N) using the Shanghai Tianma 65 m and IRAM 30 m radio telescopes. No lines belonging to acetoin were detected toward Sgr B2(N). Its upper limit of column density was calculated.

A Study of the Phosphorylcholine Polymer Coating of a Polymethylpentene Hollow Fiber Membrane.

A phosphorylcholine polymer (poly(MPC-co-BMA-co-TSMA), PMBT) was prepared by free radical polymerization and coated on the surface of the polymethylpentene hollow fiber membrane (PMP-HFM). ATR-FTIR and SEM analyses showed that the PMBT polymer containing phosphorylcholine groups was uniformly coated on the surface of the PMP-HFM. Thermogravimetric analysis showed that the PMBT had the best stability when the molar percentage of MPC monomer in the polymer was 35%. The swelling test and static contact angle test indicated that the coating had excellent hydrophilic properties. The fluorescence test results showed that the coating could resist dissolution with 90% (v/v%) ethanol solution and 1% (w/v%) SDS solution. The PMBT coating was shown to be able to decrease platelet adherence to the surface of the hollow fiber membrane, and lower the risk of blood clotting; it had good blood compatibility in tests of whole blood contact and platelet adhesion. These results show that the PMBT polymer may be coated on the surface of the PMP-HFM, and is helpful for improving the blood compatibility of membrane oxygenation.

Whole mandibular canal segmentation using transformed dental CBCT volume in Frenet frame.

Accurate segmentation of the mandibular canal is essential in dental implant and maxillofacial surgery, which can help prevent nerve or vascular damage inside the mandibular canal. Achieving this is challenging because of the low contrast in CBCT scans and the small scales of mandibular canal areas. Several innovative methods have been proposed for mandibular canal segmentation with positive performance. However, most of these methods segment the mandibular canal based on sliding patches, which may adversely affect the morphological integrity of the tubular structure. In this study, we propose whole mandibular canal segmentation using transformed dental CBCT volume in the Frenet frame. Considering the connectivity of the mandibular canal, we propose to transform the CBCT volume to obtain a sub-volume containing the whole mandibular canal based on the Frenet frame to ensure complete 3D structural information. Moreover, to further improve the performance of mandibular canal segmentation, we use clDice to guarantee the integrity of the mandibular canal structure and segment the mandibular canal. Experimental results on our CBCT dataset show that integrating the proposed transformed volume in the Frenet frame into other state-of-the-art methods achieves a 0.5%∼12.1% improvement in Dice performance. Our proposed method can achieve impressive results with a Dice value of 0.865 (±0.035), and a clDice value of 0.971 (±0.020), suggesting that our method can segment the mandibular canal with superior performance.

Integrating CRISPR-Cas12a with catalytic hairpin assembly as a logic gate biosensing platform for the detection of polychlorinated biphenyls in water samples.

Polychlorinated biphenyls (PCBs) are ubiquitous persistent organic pollutants that cause harmful effects on environmental safety and human health. There is an urgent need to develop an intelligent method for PCBs sensing. In this work, we proposed a logic gate biosensing platform for simultaneous detection of multiple PCBs. 2,3',5,5'-tetrachlorobiphenyl (PCB72) and 3,3',4,4'-tetrachlorobiphenyl (PCB77) were used as the two inputs to construct biocomputing logic gates. We used 0 and 1 to encode the inputs and outputs. The aptamer was used to recognize the inputs and release the trigger DNA. A catalytic hairpin assembly (CHA) module is designed to convert and amplify each trigger DNA into multiple programmable DNA duplexes, which initiate the trans-cleavage activity of CRISPR/Cas12a for the signal output. The activated Cas12 cleaves the BHQ-Cy5 modified single-stranded DNA (ssDNA) to yield the fluorescence reporting signals. In the YES logic gate, PCB72 was used as the only input to carry out the logic operation. In the OR, AND, and INHIBIT logic gates, PCB72 and PCB77 were used as the two inputs. The output signals can be visualized by the naked eye under UV light transilluminators or quantified by a microplate reader. Our constructed biosensing platform possesses the merits of multiple combinations of inputs, intuitive digital output, and high flexibility and scalability, which holds great promise for the intelligent detection of different PCBs.

Correction of UAV LiDAR-derived grassland canopy height based on scan angle.

Grassland canopy height is a crucial trait for indicating functional diversity or monitoring species diversity. Compared with traditional field sampling, light detection and ranging (LiDAR) provides new technology for mapping the regional grassland canopy height in a time-saving and cost-effective way. However, the grassland canopy height based on unmanned aerial vehicle (UAV) LiDAR is usually underestimated with height information loss due to the complex structure of grassland and the relatively small size of individual plants. We developed canopy height correction methods based on scan angle to improve the accuracy of height estimation by compensating the loss of grassland height. Our method established the relationships between scan angle and two height loss indicators (height loss and height loss ratio) using the ground-measured canopy height of sample plots with 1×1m and LiDAR-derived heigh. We found that the height loss ratio considering the plant own height had a better performance (R2 = 0.71). We further compared the relationships between scan angle and height loss ratio according to holistic (25-65cm) and segmented (25-40cm, 40-50cm and 50-65cm) height ranges, and applied to correct the estimated grassland canopy height, respectively. Our results showed that the accuracy of grassland height estimation based on UAV LiDAR was significantly improved with R2 from 0.23 to 0.68 for holistic correction and from 0.23 to 0.82 for segmented correction. We highlight the importance of considering the effects of scan angle in LiDAR data preprocessing for estimating grassland canopy height with high accuracy, which also help for monitoring height-related grassland structural and functional parameters by remote sensing.