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Hydrogen-atom-assisted thione–thiol tautomerization of thiourea derivatives in <i>para</i>-H2 matrix

Thiourea (TU) and its N-methylated derivative, N-methyl thiourea (NMTU), were exposed to H atoms generated in cryogenic para-H2 matrices. The reactions were followed online by FT-IR spectroscopy. The freshly deposited matrices exclusively contained the more stable thione tautomeric forms. However, upon exposure to H atoms, the peaks belonging to the precursor molecules clearly decreased along with the simultaneous appearance of new signals. These new bands could be attributed to the corresponding higher-energy thiol forms (in the case of TU) and, tentatively, to an intermediate radical (in both the TU and NMTU experiments). The radicals are suggested to be the H-atom-addition products of the TU and NMTU thione precursors, with the addition occurring on the S atom. These intermediates may then react with another free H atom, leading to the formation of the more energetic thiol tautomers, following an H-atom-abstraction process. As such, these radicals act as the centerpiece of the reaction scheme, enabling the thione–thiol tautomerization. This H-atom-assisted process is similar to that observed for the related molecule, thioacetamide. The interpretation of the experimental results was supplemented by quantum-chemical computations, which predicted all the above-mentioned reactions to be barrierless. The presence of H atoms opens a barrierless pathway; thus, the process does not necessarily require activation through irradiation (e.g., broadband UV). These findings point to the ubiquitous nature of the facile hydrogenation/dehydrogenation of the S atom, implying that thione–thiol tautomerization may occur easily.

Discovery of Carbodiimide Warheads to Selectively and Covalently Target Aspartic Acid in KRAS^G12D

Assessment of knowledge and preventive behavior regarding rubella virus among females in Riyadh, Saudi Arabia: A cross-sectional study

Background Rubella is an acute viral infection that is influenced by various factors, e.g., climate, dietary habits, and hygiene practices. This study evaluated the knowledge and preventive behaviors regarding Rubella infection among females in Riyadh, Saudi Arabia. Methods In this cross-sectional study, an online Arabic and English survey was administered using Google Forms. The survey was distributed to female participants from March 25, 2024 to May 27, 2024. The first section of the online survey covered age, gender, education level, and marital status information. The second section assessed the participants’ knowledge of rubella, including its transmission methods, symptoms, severity, concerns, and effects on pregnant females and their embryos. Finally, immunization status and prevention mechanisms were addressed in the third section. Results The online survey was completed by a total of 448 female participants. The participants consisted of 53.8% young participants (ages 18–25) from a variety of educational backgrounds, with 62.3% of them being single. The Rubella virus was acknowledged by the majority of participants (57.6%). Specifically, 57.6% of the participants asserted that they were aware of the rubella infection. Nevertheless, 51.6% were unaware of the methods by which rubella is transmitted. Furthermore, 55.4% of the participants reported that they were unaware of the significant health risks associated with rubella. The fact that 59.8% of the participants were unaware of rubella complications raises several significant questions. Fever and skin rash were identified as the most frequently reported symptoms, accounting for 23.4% of all cases. We examined the reasons for non-vaccination among the unvaccinated participants and discovered that 36.2% cited a lack of awareness. More than half of the participants (64.1%) consistently adhere to hygienic practices. Conclusion The findings of the study indicates that females in Riyadh possess adequate knowledge concerning the rubella virus. When information is available, there exists a readiness to acquire knowledge and implement preventive measures. Increased education regarding the rubella virus may enhance individuals’ willingness to engage and adopt proactive measures. Therefore, enhancing rubella prevention behaviors is crucial to mitigate the risk of infection, notwithstanding the advantages of general hygiene practices.

Pulpal responses to mineral trioxide aggregate with and without zinc oxide addition in mature canine teeth after full pulpotomy

Quantum electrodynamics formulation of multidimensional spectroscopy

We present a description of multidimensional spectroscopy, where all the light pulses are treated quantum-mechanically and the signal is expressed as a quantum dynamical map of the broadband light fields. Focusing in particular on the rephasing contribution to two-dimensional spectroscopy, we demonstrate how the semiclassical description emerges naturally as a limiting case of the quantum description. Our work establishes a formalism to apply quantum information methods to the optimization of multidimensional spectroscopy and address, e.g., fundamental resolution limits from a quantum metrological perspective.

Selective Binding and Light-Driven Release of Fluorous PF₆^– and Radioactive ⁹⁹TcO₄^– Anions for All-to-Nothing Liquid–Liquid Extraction

Genetic analysis and phytochemical profile of soursop (Annona muricata L.) cultivated in family orchards in southeastern Mexico

Annona muricata is an important and widespread neotropical perennial fruit tree, that has received increasing attention in recent years for its pharmaceutical potential, particularly for the presence of metabolites with reported anti-tumoral properties. In this study, 191 samples of this species were collected from homegardens across four states of southern Mexico. and analyzed using a dual approach, including genetic and chemical analyses. The local genetic diversity and population structure was determined through the analysis of 10 microsatellite loci- The metabolic content of flavonoids and polyphenols was analyzed at ten localities. Genetic diversity was found to be low to moderate in all populations with values of expected heterozygosity (He) ranging from 0.28 to 0.52. Our research indicated the presence of three distinct genetic groups, which did not appear to be associated with geographical origin. Variations in the chemical content of flavonoids and polyphenols were observed among the different locations examined, with flavonoid values ranging between 73.48 and 592.70 mg RE/gE and polyphenol values ranging from 13.10 to 126.59 mg GAE/gE. Accessions from Champoton and Emiliano Zapata demonstrated the highest flavonoid content, while Palenque, Champoton and Centro presented the highest polyphenol content. Multidimensional scaling (MDS) analysis revealed a correlation between genetic profiles, chemical profiles and the influence of human activity in the populations examined. This analysis revealed significant genetic differences between these populations, suggesting that they are associated with different levels of chemical contents. Remarkably, highly disturbed sites appeared to correlate with a considerable increase in chemical content.

A Radiomic-based model to predict the depth of myometrial invasion in endometrial cancer on ultrasound images

Ag/Cu2O nanoarray sensors for rapid detection of Bio-H2S in human blood

The concentration of hydrogen sulfide (H2S) in human blood is closely associated with various chronic diseases. Therefore, it is imperative to design a sensor that can conveniently, rapidly, and accurately detect H2S in human blood at room temperature. In this work, we developed an Ag/Cu2O-based sensor using a two-dimensional electrodeposition in situ assembly method for detecting biological hydrogen sulfide (bio-H2S). The morphological and structural properties indicate that a distinct contact interface has been established between Ag and Cu2O. The sensor exhibits high selectivity, good stability, and a strong linear response within the range of 50–250 μM (R2 = 0.999 58). At room temperature, the sensor displayed a remarkable response of up to 12 704.35% when exposed to 250 μM bio-H2S in blood, with a response time of just 40 s. The great sensing ability of Ag/Cu2O nanoarray for bio-H2S detection is mainly attributed to Schottky barrier modulation of Ag/Cu2O, catalytic sensitization of Ag nanowires, and vulcanization reaction of Cu2O. These results provide significant perspectives for the early diagnosis of chronic diseases and the real-time monitoring of blood-related diseases.

Proteomic Ligandability Maps of Phosphorus(V) Stereoprobes Identify Covalent TLCD1 Inhibitors

Knowledge and attitude of pregnant women about preeclampsia in King Abdulaziz Medical City, Western Region: A cross-sectional study

Introduction Preeclampsia is a serious obstetrics condition generally diagnosed by the presence of high blood pressure (≥140/90 mmHg) and significant protein in urine (≥ 2++ on dipstick urine test) developing for the first time after 20 weeks of pregnancy. It poses severe risks to both mother and newborn, including the potential for maternal and neonatal mortality and morbidity. Although preeclampsia is a well-recognized pregnancy-related complication, there is a notable lack of knowledge and awareness among pregnant women in Saudi Arabia, particularly concerning its signs, symptoms, risk factors, and the importance of timely medical intervention. This study aims to assess the level of knowledge and attitude regarding preeclampsia among pregnant women attending King Abdulaziz Medical City in Jeddah, Saudi Arabia. Methods In this quantitative cross-sectional study, 122 pregnant women visiting the Obstetrics and Gynecology Outpatient Department were surveyed from April to June 2023. The research employed a structured questionnaire to collect detailed information on participants’ sociodemographic backgrounds, knowledge about preeclampsia symptoms, risk factors, complications, and attitudes toward its prevention and the recognition of danger signs. Data were analyzed using descriptive statistics as well as ANOVA test, T-test, and Pearson correlation to explore relationships and significance among study variables. Results The study revealed an average knowledge score of 25.43 (SD = 5.67), indicating that many participants demonstrated a moderate understanding of preeclampsia. On the other hand, the attitude score averaged 23.39 (SD = 3.11), showing that participants held favorable attitudes toward the risk factors, prevention, and complications of preeclampsia. Notably, participants with higher education levels and those who were employed demonstrated higher knowledge scores. Conclusion The findings reflect a moderate level of understanding among participants but also highlight critical areas where knowledge enhancement is necessary to enable timely intervention and reduce adverse maternal and neonatal outcomes.

Dyads use heuristics to minimise time costs during joint action

Abstract Research on joint action planning has demonstrated that, when acting with others, individuals will choose more effortful actions if it improves co-efficiency by reducing the overall effort exerted by the group. However, because these studies use actions for which time and effort costs are confounded, it is unclear which costs participants sought to minimise and what processes underlie decision-making about individual contributions to joint actions. Across three experiments, we tested (1) whether dyads aim to minimise effort vs. time costs (Experiments 1–2) and (2) whether individuals choose actions based on a rational, deliberative process or a heuristic (Experiment 3). Data from a joint object-dragging computer task revealed that participants chose to drag objects to the closer of two goals even when it required more effort from the dyad (Experiments 1–2). Participants preferred closer goals when time and effort costs were equal (Experiment 3a), but only when the objects’ locations were salient (Experiment 3b). Together, these results suggest that: (1) individuals minimise time, rather than effort, when sharing object-moving tasks, and (2) they do so – at least in part - by using distance as a heuristic. Our findings also replicate and extend earlier work showing that people prefer acting together versus alone, even when this is less efficient.

Analysis of variants of non-adiabatic ring polymer molecular dynamics for calculating excited state dynamics

The non-adiabatic ring polymer molecular dynamics (NRPMD) method, which combines the path-integral ring polymer molecular dynamics framework for the nuclei with the Meyer–Miller–Stock–Thoss mapping of the electronic states, is a powerful tool for simulating non-adiabatic dynamics including nuclear quantum effects. However, challenges arise in utilizing NRPMD associated with zero-point energy leakage between the electronic and nuclear degrees of freedom and ambiguities in how to apply the method under non-equilibrium conditions. Here, we explore several variants of NRPMD and compare their performance using a set of benchmark systems for excited-state electronic population dynamics. Within this context, we adopt an idea from recent work on the linearized semi-classical initial value representation and derive a new NRPMD correlation function for the population of the electronic states in terms of a trace-less operator and the identity operator. The in-depth analysis of the different choices when utilizing NRPMD provides new insight into the practical implementation of the method and related techniques.

Enhanced Catalytic Activity via Rapid Two-Electron Transfer in Low-Spin Fe(II) Complex and Spin-State Dependent Proton Reduction Pathways

Immunization status of children with cerebral palsy: A cross-sectional hospital-based study in Vietnam

Aim To describe the immunization status of children with CP in Vietnam and identify factors associated with vaccine non-uptake in this group. Methods We conducted an active prospective case ascertainment of children with cerebral palsy (CP) attending the National Children’s Hospital in Hanoi between June to November 2017, following the model proposed by the Paediatric Active Enhanced Disease Surveillance system in Australia. All children were assessed by trained paediatricians at the hospital and their immunization history was recorded. Results Data were collected from 765 children with CP (median age = 1.7 years, IQR = 2.7 years). Of these children, 82.7% were fully immunized for their age (compared to 96.4% of the general child population) according to the Vietnamese Expanded Programme on Immunization (EPI) schedule. A BCG vaccination scar was present in 94.0% of children with CP, and 95.9% of eligible children had received the measles-rubella vaccine as part of the national campaign (compared with 96.0% and 98.2% of the general population respectively). Incomplete vaccination according to the EPI was associated with younger age, living in an earth/sand house, homebirth, low-level maternal education, being diagnosed with CP before the age of three, having bilateral CP, having associated impairments (i.e., epilepsy, intellectual, visual, speech), being at level IV-V on the Gross Motor Function Classification System, and being undernutrition. Conclusion This is the first study to document the immunization status of children with CP in Vietnam. A large proportion had not received the measles-rubella vaccine and 17.3% were not fully immunized. To increase vaccination coverage, interventions and strategies are required to ensure that all children with CP have equitable access to early diagnosis, immunization, health education programs, outreach programs, and frequent follow-up. Early diagnosis and focused intervention in early life could further improve vaccination coverage in children with CP.

Establishing altitude-based coagulation reference ranges in Western Sichuan

Low energy electron induced fragmentation of hot asparagine and aspartic acid molecules

Asparagine (Asn) and aspartic acid (Asp) are not only amino acids found in proteins but also building blocks for synthesis of eco-friendly polymers with techniques such those in which electrons play a role. In this contribution, we present a comparative study of dissociative electron attachment (DEA) to Asn and Asp under gas-phase conditions by means of DEA spectroscopy. In contrast to a number of amino acids studied so far, the formation of the dehydrogenated parent anion, (M – H)−, at about 1.2 eV from both investigated compounds is not the most intense dissociation channel. On the other hand, prominent negative ion resonances are observed peaking below 0.5 eV, resulting in the formation of fragment anions generated from a loss of a neutral –COOH group or neutral H2O2 molecule or leading to the production of HCOO− from both asparagine and aspartic acid. It should be stressed here that the surrogation of one hydroxyl group by an amino group in aspartic acid, which results in the formation of asparagine, sensitizes the latter compound for the loss of an entire neutral carboxyl group. Indeed, the formation of the (Asn – COOH)− anion from DEA to asparagine is more efficient by about an order of magnitude than the formation of the (Asp – COOH)− anion from DEA to aspartic acid.

Insight into the Catalytic Nature of Lithiophilicity for High-Energy-Density Lithium Metal Batteries

Animal models in preclinical metastatic breast cancer immunotherapy research: A systematic review and meta-analysis of efficacy outcomes

Breast cancer, particularly metastatic breast cancer (MBC), presents aggressive clinical challenges with limited treatment success. Immunotherapy has emerged as a promising approach, however, discrepancies between preclinical animal models and human cancers complicate translation to clinical outcomes. This systematic review and meta-analysis evaluated the effect of immunotherapy on primary and metastatic tumor regression in animal models of MBC and assessed the models’ appropriateness and reproducibility to improve future preclinical study design. Following a preregistered protocol in PROSPERO (CRD42021207033), we conducted searches in MEDLINE, Embase, and Web of Science databases, yielding 2255 studies for title/abstract screening and 108 studies included after full-text screening. All included studies used mouse models, assessing primary outcomes through tumor volume or weight and metastatic outcomes via nodule count or bioluminescence. Only 14% of studies fully reported experimental animal characteristics, and 43% provided detailed experimental procedures. Of 105 articles (293 comparisons) included in the meta-analysis, pooled effect sizes indicated significant reductions in both primary and metastatic tumors. However, high heterogeneity across studies and wide prediction intervals suggested substantial variability in model responses to immunotherapy. Univariable and multivariable meta-regressions failed to significantly explain this heterogeneity, suggesting additional factors may influence outcomes. Trim-and-fill and Egger’s regression tests indicated funnel plot asymmetry, implying potential publication bias and small study effects. While our analysis demonstrated positive effects of immunotherapy on MBC and highlighted variability in animal tumor models, addressing model-related heterogeneity and enhancing methodological transparency are essential to improve reproducibility and clinical translatability.

Establishment and solution of a three-zone radial composite well test model for mixed gas drive production wells

Abstract In the process of gas flooding, the underground miscible law and oil displacement characteristics are complex, and there is no effective evaluation method. As an effective method to invert reservoir parameters and analyze seepage law, well test can be used to analyze the law of underground gas and oil action. This study focuses on the mechanism of gas-crude oil interaction, and establishes a three-zone radial composite well test model including interface skin effect and power-law change of physical properties of transition zone. The model innovatively introduces the interface coefficient to characterize the phase transition effect of the regional boundary, which is solved by dimensionless transformation, Laplace transformation and Stehfest numerical inversion method. Get the fluid phase distribution evaluation chart in the process of gas flooding. The results show that the radius of the crude oil zone (R 1 ) determines the duration of the radial flow, the radius of the gas-oil transition zone (R 2 ) regulates the seepage range, the power law index (θ) controls the derivative curve shape, and the energy storage index (I) has a weak influence on the curve shape. This study establishes a theoretical framework for dynamic monitoring of miscible gas drive wells and nonlinear reservoir parameter inversion.