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Breakthrough hepatitis B virus infection and its associated factors among vaccinated children in Northwest Ethiopia
Excited-state properties of functionalized corrole photosensitizers: Insights from ultrafast experiments and quantum mechanical calculations
Corrole complex, as a new generation of porphyrin photosensitizer, shows promising applications in photodynamic therapy and optical imaging due to their unique structure and properties. However, lack of comprehensive understanding of the relationship between structure and property limits tailored preparation of demanding corroles. Here, we systematically investigate the excited-state properties of corrole complexes with diverse peripheral substitutions and central atom coordination through time-resolved fluorescence, femtosecond transient absorption spectra, and time-dependent density functional theory calculations. The results indicate that aromatic substituents affect frontier molecular orbitals, prompting intramolecular charge transfer. Coordination with main group P(V) and Ga(III) enhances macrocycle rigidity and symmetry, significantly boosting fluorescence emission rates and absorption efficiency of the Soret band, while improving intersystem crossing probabilities. Transition metal Mn(III) accelerates charge transfer from ligands to metal and shortens internal conversion and intersystem crossing times via d–pπ bonding interaction. This study establishes a foundational understanding for designing high-performance photosensitizers.
Mechanical and transport properties of concrete incorporating recycled crushed clay bricks as coarse and fine aggregates
Abstract Recycling crushed clay bricks as both coarse and fine aggregates has shown promising potential for producing eco-friendly concrete, helping to reduce the industry’s environmental footprint while promoting the sustainable reuse of waste materials. However, the inherent variability of these aggregates can lead to inconsistent concrete performance, emphasizing the need for a thorough investigation to assess their suitability for construction applications. For this purpose, a number of concrete mixtures incorporating crushed clay bricks as coarse and/or fine aggregates were produced and tested in this study. Specifically, four mixtures incorporating crushed clay coarse aggregate (CCCA) and another four incorporating crushed clay fine aggregate (CCFA), each at replacement levels of 25%, 50%, 75%, and 100% (by volume). Additionally, one mixture was fully developed using both CCCA and CCFA. For comparison, a control mixture containing 100% natural coarse and fine aggregates was also tested. The properties evaluated for all the developed mixtures included slump, dry density, water absorption, sorptivity, compressive strength, splitting tensile strength, flexural strength, abrasion resistance, impact resistance, ultrasonic pulse velocity, and Schmidt rebound hammer. All results were statistically analyzed to assess the effect of CCCA and/or CCFA on the test outcomes and their significance. The results indicated that replacement levels of CCCA up to 25% and CCFA up to 50% could offer a viable alternative to conventional natural aggregates, while minimizing the deterioration of concrete properties. At any same replacement level, CCFA generally outperformed CCCA, except in abrasion resistance, where CCCA mixtures exhibited better performance. As for the sorptivity, the CCFA improved the capillary structure of concrete leading to lower water ingress, while the CCCA resulted in larger capillary pores and higher sorptivity values compared to the control mix. Under impact loading, replacing more than 25% of the aggregates with either CCCA or CCFA resulted in a significant reduction in the energy absorption capacity of the specimens, thus limiting their suitability for applications exposed to high impact loads. However, combining both CCCA and CCFA at full replacement levels can effectively produce sustainable semi-lightweight concrete with strengths above 25 MPa, making it suitable for various structural applications, although its suitability for environments requiring high abrasion and impact resistance is limited. The findings also suggest that non-destructive tests such as the Schmidt hammer and UPV tests can be used for assessment, with the Schmidt hammer test providing more reliable results for evaluations and estimations. Statistical analysis showed that CCCA, CCFA, and their interaction significantly affected most concrete properties. However, their use resulted in higher variability than natural aggregates, especially in splitting tensile strength, abrasion, and impact energy tests. While CCCA reduces embodied energy compared to natural coarse aggregates, the use of CCFA increases it, though CCFA remains a sustainable alternative for natural sand, aiding in resource conservation.
Nuclear quantum and H/D isotope effects on hydrogen-bond symmetrization in lithium hydroxide crystals at high pressure
Molecular crystals with hydrogen bonds undergo a phase transition and symmetrization of the hydrogen-bond network at high pressures. Lithium hydroxide (LiOH) also undergoes a similar phenomenon; however, the pressure at which it occurs remains unclear. This study employed the path integral molecular dynamics (PIMD) and static density functional theory calculations to investigate hydrogen-bond symmetrization in LiOH crystals at high pressures. The nuclear quantum effects centralized the protons and significantly lowered the pressure required for hydrogen-bond symmetrization (∼500 GPa in PIMD, compared with the 1200 GPa recorded in the static density functional theory calculations). Furthermore, the pressure required for symmetrization in the deuterated system [PIMD(D)] was higher than that required in the nondeuterated system [PIMD(H)]. This indicated that the H/D isotope effect significantly affects the hydrogen-bond symmetrization. These results demonstrate that nuclear quantum and isotope effects significantly affect hydrogen-bond symmetrization in LiOH under extreme conditions.
Experimental investigation of sensitivity changes during encapsulation of piezoelectric composite materials
Abstract Piezoelectric (0-3) composites typically consist of a polymer matrix that contains piezoceramic particles. They can be used as sensors for structural health monitoring due to their lower acoustic impedance and ability to detect high-frequency waves. These composites have two thin electrodes on their surfaces, and cable connections that require electrical insulation. This insulation increases the durability of the sensor and provides additional protection. One way to achieve this is by encapsulating the sensor in polymer films. However, the sensitivity of the sensor may decrease due to an increase in overall stiffness after encapsulation, so this must also be evaluated. This study experimentally investigates and compares three different encapsulation designs with a non-encapsulated reference sample. The designs include (i) gluing and laminating the sensor onto a pre-prepared flexible printed circuit board, (ii) lamination of the sensor with polyethylene terephthalate, and (iii) lamination with polyetherimide. The sensitivity of the encapsulated sensors to low and high frequency vibrations was evaluated. The results show that an encapsulation sensor with adhesive tape and polyetherimide results in slightly lower sensitivity at lower frequencies, but almost no difference at higher frequencies. These results suggest that the proposed method is suitable for encapsulating sensors for use in structural health monitoring applications.
Asymmetric hydrophilic/hydrophobic nanoconfinement directs novel two-dimensional ice structures and phase transitions
Understanding the phase and dynamic behaviors of nanoconfined water is of critical importance for both fundamental scientific research and technological applications. Although numerous studies have investigated nanoconfined water systems, most have exclusively focused on symmetric hydrophobic confinement. In contrast, the phase behavior of water under asymmetric hydrophobic/hydrophilic confinement remains poorly understood. Here, we systematically studied the compression properties, phase diagram, and freezing/melting transitions of two-dimensional (2D) water/ice (monolayer to trilayer) confined between mica and graphene nanoslits. We establish a compression phase diagram in the plane of nanocapillary width and pressure, revealing that symmetry breaking of water–surface interactions induces unique 2D ice structures. In particular, we report four previously unidentified 2D ice phases: monolayer triangular ice (ML-TI), bilayer AA- and AB-stacked triangular/hexagonal mixed ice (BL-AB-THMI and BL-AA-THMI), and trilayer triangular/hexagonal mixed ice (TL-THMI). These structures emerge from the synergistic interplay between the templating effect of the mica surface and confinement effects. Our study fills a fundamental gap in the physics of asymmetric nanoconfinement, provides new mechanistic insights into structural transitions, and offers guidance for nanotechnology applications.
Cross-talk between dopamine and noradrenaline modulates glutamatergic transmission in the deep cerebellar nuclei
High-precision quantum dynamics of He2 over the b 3Πg–c 3Σg+ electronic subspace by including non-adiabatic, relativistic, and QED corrections and couplings
Relativistic, quantum electrodynamics, and non-adiabatic corrections and couplings are computed for the b 3Πg and c3Σg+ electronic states of the helium dimer. The underlying Born–Oppenheimer potential energy curves are converged to 1 ppm (1: 106) relative precision using a variational explicitly correlated Gaussian approach. The quantum nuclear motion is computed over the b 3Πg–c3Σg+ (and B 1Πg–C1Σg+) 9-(12-)dimensional electronic-spin subspace coupled by non-adiabatic and relativistic (magnetic) interactions. The electron’s anomalous magnetic moment is also included; its effect is expected to be visible in high-resolution experiments. The computed rovibronic energy intervals are in excellent agreement with the available high-resolution spectroscopy data, including the rovibronic b 3Πg-state fine structure. Fine-structure splittings are also predicted for the c3Σg+ levels, which have not been fully resolved experimentally, yet.
Decades of land use change and its impact on air quality in Egypt’s Middle Nile Delta observed from space
Abstract Air pollution has become one of the most pressing environmental challenges globally, with significant consequences for public health and ecosystems. Recently, Gharbia Governorate has undergone remarkable changes in land use/land cover (LULC), leading to a variety of environmental impacts. These transformations have raised concerns about their potential influence on air quality, making it crucial to investigate how shifts in LULC are affecting pollution levels in the region. Understanding this relationship is vital for developing sustainable land management strategies and improving air quality monitoring in the area. This study aims to employ remotely sensed data integrated with Geographic Information System (GIS) to monitor the LULC changes and evaluate their influences on the governorate’s air quality. Two Landsat 8 Operational Land Imager data, as OLI acquired in 2023, 2013, and Landsat 5 Thematic Mapper data, as TM 5 acquired in 2003, were used. A maximum likelihood classifier was used to produce a land cover map and track changes in land cover of the study area. Aqua, Terra, and Sentinel-5P were employed to measure the PM2.5, CO, NO2, and SO2 concentrations. The classification results identified two dominant LULC classes: cultivated land and urban area. Between 2003 and 2023, urban areas increased by 136.2 km2, while cultivated lands declined by 135.94 km2, reflecting significant urban expansion. This land conversion was associated with a marked impact on air quality. PM2.5 concentrations ranged between 7.12 and 8.66 µg/m3 during the study period. Notably, NO2 levels peaked during autumn (3.13 µg/m3), while elevated CO and SO2 concentrations were observed in summer (946.79 µg/m3) and winter (8 µg/m3), respectively. The highest pollutant levels were consistently recorded in the recently expanded urban areas compared to other land use categories. These findings demonstrate that urban sprawl has a significant and direct impact on air quality, highlighting the need for integrated land-use planning and air pollution control. The generated data provides a valuable foundation for sustainable development and environmental decision-making in Gharbia Governorate.
Note: Improved boundary homogenization for a sphere with an absorbing cap of arbitrary size
Finding accurate approximations for the effective reactivity of a structured spherical target with a circular absorbing patch of arbitrary size is a long-standing problem in chemical physics. In this Note, we reveal the limitations of the empirical approximation proposed in Dagdug et al., [J. Chem. Phys. 145, 214101 (2016)]. We show that the original approximation fails at large patch surface fractions σ and propose a simple amendment. The improved approximation is validated against a semi-analytical solution and is shown to be accurate over the entire range of σ from 0 to 1. This approximation also determines the probability of reaction on the patch and the capacitance of such a structured target.
Performance analysis of concatenated Reed–Solomon and next generation polar codes for 6G communication systems
Study of concentration dependent microstructures and dynamic behaviors of aqueous CaCl2 solutions via deep potential with electrostatic interactions
Salt solutions have long been a subject of scientific interest owing to their significant role in various applications. Despite advances in experimental techniques and simulation methods, contradictions persist in describing the solvation structure and dynamic behavior of ions and water molecules in salt solutions, especially for non-monovalent salt solutions. In this study, we focus on the aqueous CaCl2 system and developed an advanced machine learning force field that incorporates electrostatic interactions, enabling high-accuracy molecular dynamics simulations at the SCAN functional level on nanosecond timescales. Benchmark tests confirmed that our model closely matches both density functional theory results and experimental data. Through comprehensive analysis, the concentration dependence of the microscopic structure and dynamics of CaCl2 solutions was revealed, highlighting significant effects arising from ion species. In addition, we performed the first high-precision infrared spectroscopy simulation of CaCl2 solutions, validating changes in hydrogen bond networks, ion solvation shells, and water molecule dynamics. Our results describe the dependence of solvation structure and diffusion behavior in CaCl2 solutions, offering the theoretical foundation for future research in this field.
Enhancement solar dryer performance and collector efficiency of paraffin PCM/copper fin featured solar dryer
When will dengue strike? Outbreaks sync with heat and rain
Generalizing machine learning models from clinical free text
Abstract To assess strategies for enhancing the generalizability of healthcare artificial intelligence models, we analyzed the impact of preprocessing approaches applied to medical free text, compared single- versus multiple-institution data models, and evaluated data divergence metrics. From 1,607,393 procedures across 44 U.S. institutions, deep neural network models were created to classify anesthesiology Current Procedural Terminology codes from medical free text. Three levels of text preprocessing were analyzed from minimal to automated (cSpell) with comprehensive physician review. Kullback–Leibler Divergence and k-medoid clustering were used to predict single- vs multiple-institutional model performances. Single-institution models showed a mean accuracy of 92.5% [2.8% SD] and 0.923 [0.029] F1 on internal data but generalized poorly on external data (− 22.4% [7.0%]; − 0.223 [0.081]). Free text preprocessing minimally altered performance (+ 0.51% [2.23]; + 0.004 [0.020]). An all-institution model performed worse on internal data (-4.88% [2.43%]; − 0.045 [0.020]), but improved generalizability to external data (+ 17.1% [8.7%]; + 0.182 [0.073]). Compared to vocabulary overlap and Jaccard similarity, Kullback–Leibler Divergence correlated with model performance (R2 of 0.41 vs 0.16 vs 0.08, respectively) and was successful clustering institutions and identifying outlier data. Overall, pre-processing medical free text showed limited utility improving generalization of machine learning models, single institution models performed best but generalized poorly, while combined data models improved generalization but never achieved performance of single-institutional models. Kullback–Leibler Divergence provided valuable insight as a reliable heuristic to evaluate generalizability. These results have important implications in developing broad use artificial intelligence healthcare applications, providing valuable insight into their development and evaluations.
Investigation of antibacterial and wound healing activities of the extract of Rhodotorula mucilaginosa endophyte isolated from cucumber leaves
Abstract Endophytic fungi represent a reservoir of pharmacologically essential secondary metabolites. The current study focused on the antibacterial properties of the endophytic yeast-like fungus Rhodotorula mucilaginosa (R. mucilaginosa) isolated for the first time from Cucumis sativus (cucumber) leaves. After isolation, R. mucilaginosa was identified by 18S rRNA gene sequencing and was cultured on Asian rice for production of fungal metabolites. Then, its phytochemical profile was elucidated using LC–HRESI–MS/MS technique to reveal 22 compounds which are mainly carotenoids and fatty acids in nature. Dried ethyl acetate extract of R. mucilaginosa was tested for antimicrobial activity against Pseudomonas aeruginosa isolates. The extract of R. mucilaginosa (ERM) showed minimum inhibitory concentrations with a range from 64 to 512 µg/mL. The crystal violet assay was utilized to determine the effect of ERM on the tested isolates’ ability to produce biofilms. The percentage of strong biofilm-forming isolates dropped from 20 to 3.3% and 10%, respectively, after the treatment with ½ and ¼ MICs of ERM. When tested isolates of P. aeruginosa were exposed to sub-MICs of ERM, their cell size significantly decreased, and their biofilm matrix was reduced. The in vitro anti-inflammatory activity of ERM was supported by the marked decrease in TNF-α gene expression in the cells treated with either ERM or piroxicam compared to the control cells. The wound healing effect of ERM was investigated in vitro, where ERM showed improvement in the wound healing process. In addition, the wound healing effect of ERM was investigated in vivo using a model of infection in rats, where the wounds were infected with P. aeruginosa. The histological investigation of the wound showed a remarkable improvement in the group treated with ERM. Therefore, further investigation is required to explore the possible application of ERM as a potential antibacterial agent, which could aid in our fight against pathogenic microbes that have become resistant.