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Retraction Note: Effect of radiotherapy on head and neck cancer tissues in patients receiving radiotherapy: a bioinformatics analysis-based study
Cold collisions of highly vibrationally excited and aligned D2 with Ne
Resonant scattering of highly vibrationally excited and aligned D2 in cold collisions with Ne has recently been probed experimentally using the Stark-induced adiabatic Raman passage technique [Perreault et al., J. Chem. Phys. 157, 144301 (2022)]. A partial-wave analysis and numerical fitting of the experimental data attributed the measured angular distribution to an l = 2 shape resonance near Ec/kB = 1 K (≈0.7 cm−1). Here, we report the computation of a new potential energy surface for the Ne–H2 interaction suitable for the study of collisions between highly vibrationally excited H2/D2 with Ne as well as quantum scattering calculations of stereodynamics of D2 (v = 4, j = 2) + Ne collisions probing Δj = −2 rotational transition in D2. Our results show that collisions are dominated by a strong l = 5 resonance near 3 K (≈2.09 cm−1) and a weaker l = 6 resonance near 8 K (≈5.56 cm−1) and not an l = 2 resonance, as suggested in the analysis of the experimental data. A reasonable agreement between our calculations and the experiments is obtained only when an artificial energy cutoff is applied to the integral over the collision energy to exclude contributions from the l = 5 resonance while retaining contributions from l = 0, 1, and 2. However, our calculations do not support the claim that the measured angular distributions are dominated by a single l = 2 partial-wave resonance characteristic of orbiting collisions.
Axial compression behavior and failure mechanism of CFRP-confined circular hollow steel tube short columns: Theoretical and numerical analysis
Circular hollow steel tubes (CHST) are widely employed as short columns in various infrastructure applications. This study comprehensively investigates the mechanical behavior of CFRP-Confined CHST (CFRP-CHST) short columns under axial compression through theoretical research, finite element analysis, and existing experimental data. New theoretical formulas for calculating the yield and ultimate bearing capacities of CFRP-CHST short columns under axial loading are developed based on continuum mechanics and the limit equilibrium method. The accuracy and reliability of these formulas are validated through comparisons with finite element simulations and experimental results. Theoretical analysis reveals that CFRP provides only a modest enhancement to the yield-bearing capacity of CHST short columns. However, within a certain range of CFRP layers, the ultimate bearing capacity is significantly improved, albeit with limitations. The concept of the CFRP confinement coefficient is introduced to define the effective range in which CFRP reinforcement substantially enhances the bearing capacity of CHST short columns. The mechanisms restricting this enhancement are investigated in detail through experimental data and finite element analysis. This research offers valuable design and analysis methods for the engineering applications of CFRP-CHST short columns.
An open source simulator for prism sensors based on lossy mode resonance effect
Double aromaticity in the triplet ground state of Be2©Be6H6: A 4π Baird and 6σ Hückel electron system
The lowest-energy structure of Be8H6 adopts a distinctive star-like configuration (Be2©Be6H6), consisting of a Be2 dimer oriented orthogonally to a planar hexagonal Be6H6 ring, with hydrogen atoms bridging the outer edges. This system, characterized by D6h symmetry and a triplet ground state (3A1g), features an exceptionally short Be–Be bond length of 1.874 Å. Chemical bonding analysis reveals a rare dual aromaticity: six delocalized σ electrons conform to the 4n + 2 Hückel rule, while four delocalized π electrons satisfy the 4n Baird rule. Notably, Be2©Be6H6 represents the first example exhibiting both π-Baird and σ-Hückel dual aromaticity. Covalent dative interactions between the s/p orbitals of the Be2 dimer and the delocalized Be6H6 framework contribute to the exceptional stability of this system. This study demonstrates the effectiveness of integrating multiple aromaticity frameworks, specifically Hückel and Baird aromaticity, in designing and stabilizing novel inorganic systems.
Evaluating the effectiveness of speed humps and rumble strips in improving pedestrian safety in Addis Ababa, Ethiopia
Pedestrian fatalities remain a major road safety problem in Addis Ababa. To address this problem, speed humps and rumble strips were introduced on high-crash road segments in the city in 2017. As a case study that can be useful elsewhere, the aim of this research is to evaluate the effectiveness of speed hump with rumble strips in Addis Ababa. This study uses descriptive and inferential statistics to evaluate the impact of these interventions. Crash data between 2014 and 2021, excluding 2017 when the measures were implemented, is used in the analysis. The interventions led to a 25.08% reduction in operating speeds, with statistically significant speed reductions for passenger cars. Our findings on the extent to which speed humps and rumble strips lowered the speed of buses and trucks are not conclusive. Notable speed drops were observed at humps in some road segments while humps had no appreciable effect on speed in others. This underscores the need for additional measures or other approaches to reduce the operating speed of buses and trucks. The equivalent crash number for pedestrian crashes reduced by 24.45% and total crashes dropped by 51.14%. While crashes involving pedestrians crossing roads reduced, those involving pedestrians walking along travel lanes increased by 15.94%. These mixed results suggests that the effectiveness of speed humps and rumble strips depends on the type of crash being addressed and the category of vehicle involved.
Characterization of pain behaviors in kittens following ovariohysterectomy using video assessment
Thermodynamic insights into polyelectrolyte complexation: A theoretical framework
In this study, we propose a theoretical framework to explore the interactions between flexible polymer chains, specifically polyelectrolytes (PEs). Our analysis reaffirms that the thermodynamic drive for complex coacervation is influenced by key factors such as the number of ions bound to the polymer backbone and the entropy associated with free ions. By calculating the free energy of the system while considering position-dependent mutual interactions and chain conformations, we gain valuable insights into the local dielectricity as PEs overlap. Our findings indicate that global thermodynamic behavior is significantly shaped by local factors such as dielectric constant, providing an explanation for the discrepancies observed between experimental and computational studies. In addition, we found that entropy gain is inversely proportional to the local dielectric constant, provided that the electrostatic temperature remains constant. This relationship underscores the importance of polymer-specific parameters when examining the thermodynamic behavior of charged polymer complexation.
Are you with me? Co-occurrence tests from community ecology can identify positive and negative epistasis between inversions in Mimulus guttatus
Chromosomal inversions are structural genetic variants that can play a crucial role in adaptive evolution and speciation. Patterns of attraction and repulsion among unlinked inversions — whether they tend to be carried by the same or different individuals— can indicate how selection is acting on these polymorphisms. In this study, we compare analytical techniques using data from 64 inversions that segregate among 1373 F2 plants of the yellow monkeyflower Mimulus guttatus. Mendelian assortment provides a strong null hypothesis for χ2 contingency tests. Here, we show how co-occurrence metrics used in community ecology can provide additional insight regarding coupling and repulsion of inversions at genotypic level. The centered Jaccard/Tanimoto index and the affinity score describe the specific way that inversions interact to generate epistasis for plant survival. We further explore the use of network analysis to visualize inversion interactions and to identify essential third and fourth order interactions, which expand the traditional pairwise scope of the co-occurrence metrics. We suggest that a combination of different statistical approaches will provide the most complete characterization of the fitness effects, both for inversions and other polymorphisms essential to adaptation and speciation.
Choroidal vessel changes in acute and chronic central serous chorioretinopathy assessed by en-face Layer-by-Layer comparison and correlation
Ostwald ripening of buoyancy-driven microbubbles
Microbubble solutions have a wide range of industrial applications, including heat transfer, agriculture, and water treatment. Therefore, understanding and controlling the variation in bubble sizes is critical. In this study, we develop a theoretical framework for Ostwald ripening of buoyancy-driven microbubbles by introducing a height-dependent size distribution function. For the first time, we show that the population balance equation in steady state can be interpreted within the Lifshitz–Slyozov–Wagner theory when the distribution function is redefined as the density distribution of the buoyancy-induced flux. Notably, in this form of Ostwald ripening, the distribution function approaches a scaled universal distribution, not over time, but as a function of height. We analytically derive the scaled universal distribution and show that the fifth power of the mean radius of the bubbles grows linearly with height.
Psycho-oncology practice for cancer patients during the pandemic lockdown in Italy: A qualitative mixed-method study with psychotherapists
Background At the beginning of the COVID-19 outbreak, psychotherapy practice underwent a drastic reorganization. To enhance knowledge of the challenges healthcare professionals faced during the pandemic, this study explores the experiences and practices of Italian psychotherapists caring for cancer patients during the first phase of the COVID-19 pandemic. Method This mixed-method study consists of a qualitative cross-sectional survey followed by open-ended semi-structured interviews with a subsample of survey respondents. The data were then triangulated to depict better the experience of caring for cancer patients from the psychotherapists’ perspective. Results The final dataset included 102 valid responses. Subsequently, one male and 21 females participated in the interview-based study. Qualitative analysis revealed four themes and specific subthemes: 1. patient relationships (the impact of restrictions on family ties, the impact of restrictions within the healthcare environment), 2. clinical practice management (the use of technologies for psychological interventions, timing and continuity of care, changes in the number of requests for psychological interventions), 3. emotional aspects (emotions captured in patients, emotions captured in other professionals, the inner world of the psychotherapists), and 4. organizational recognition (investments in psychological support and service coordination, issues related to employment status). Conclusion Our findings provide knowledge of the pandemic’s impact on psycho-oncology practice, offering further input for research on innovative tools in psychotherapy and staff support programs and the development of psycho-oncology services that can systematically respond to the multifaceted needs of cancer patients, relatives, and healthcare professionals.
Projectile weapon injuries in the Riparo Tagliente burial (Veneto, Italy) provide early evidence of Late Upper Paleolithic intergroup conflict
Improved heteronuclear decoupling performance under fast MAS by Slightly Desynchronized Phase Alternated Cycles (SDPACs)
A new version of the recently introduced Rotor-Synchronized Phase-Alternated Cycle (ROSPAC) heteronuclear decoupling pulse sequence [Simion et al., J. Chem. Phys. 157, 014202 (2022)] is proposed, where the delay between the pulses is not perfectly rotor synchronized, dubbed slightly desynchronized phase alternated cycles. Its efficiency in terms of the spectral line’s intensity and robustness toward 1H offset and flip angle is analyzed by experimental measurements at 100 kHz magic-angle spinning and theoretically explored by using a generalized theoretical framework based on Floquet theory. The best decoupling was found for a delay between the pulses that has a deviation of about 10% from the perfect synchronization condition, with an enhancement of the signal’s intensity of up to 20% compared to the original ROSPAC sequence.
Research on the performance of phase change energy storage devices based on solar energy
This article designs a high-altitude border guard post that can fully utilize the heat absorbed by solar collectors to continuously store thermal energy during the day and stably release heat at night. This device is a spherical encapsulated paraffin phase change heat exchanger device (stainless steel shell diameter: 80mm),By conducting thermal storage and release experiments on the device, the performance of the device was analyzed. The experimental results showed that in the thermal storage experiment, the outlet temperature of the hot fluid reached about 97 °C at about 500 minutes and tended to stabilize. The wall temperature and center temperature of the encapsulated paraffin sphere began to stabilize at about 450 minutes and stopped absorbing heat; In the heat release experiment, the wall temperature and core temperature of the encapsulated paraffin spheres stabilized at about 400 minutes and stopped releasing heat; In this way, it can meet the heating needs of storing heat for about 8 hours during the day and continuously releasing heat for 6.5 hours at night.
Designing sustainable cement free compositions with rice husk ash to improve mechanical performance in next generation ecoblocks
Conformational equilibrium of aminoethanol in the gas phase and in solution driven by intra- and intermolecular interactions and solvent polarity
The study on the conformational equilibrium of small flexible molecules under different environments is essential to understand the folding motives in complex molecules. Aminoethanol (NH2CH2CH2OH) is a typical flexible molecule with rich conformational isomerism, but its conformational diversity in the gas phase or solutions is not yet fully understood. Owing to well-separated peaks and the absence of intermolecular interactions, gas-phase Raman spectroscopy is a valuable tool for characterizing molecular conformations. Using temperature-dependent photoacoustic Raman spectroscopy (PARS), the gas-phase Raman spectra of aminoethanol were measured in the O–H and C–H stretching regions. The analysis of the observed gas-phase Raman spectra, together with theoretical calculations, allows us to identify one O–H⋯N intramolecular H-bonded conformer (g′Gg′) and four free-OH conformers (gGt and tGt, gGg and tGg). Furthermore, using the assigned gas-phase conformers, the conformational changes of aminoethanol were investigated in the nonpolar CCl4 and polar water solutions, respectively. It was shown that intramolecular H-bonds are unlikely to be a significant factor in the conformational equilibrium of liquid aminoethanol, whereas the gauche effect is clearly very important. In addition, the concentration-dependent Raman spectra in aqueous solution revealed that aminoethanol molecules prefer the tGt conformation upon dilution with water. This can be ascribed to the fact that polar water molecules push aminoethanol conformers toward a higher dipole moment rather than a lower one, which is in good agreement with recent molecular dynamic simulations. Our findings deepen the understanding of the effect of ruling conformational stability and shed light on molecular switches that are activated in different solvent environments.
Prevalence, risk and protective factors of burnout among Korean hospitalists
Background Burnout among healthcare professionals is a critical factor which affects patient safety, treatment outcomes, and the quality of care. This is especially important for hospitalists who manage inpatient care, yet no studies have been conducted on this issue in Korea. This study aimed to investigate burnout and psychiatric symptoms among hospitalists in Korea, as well as to identify the risk and protective factors associated with these issues. Materials and methods A cross-sectional online survey was conducted targeting all hospitalists in Korea (n=303), and 24.1% (n=79) completed the survey. The Maslach Burnout Inventory–Human Services Survey was used to measure burnout; the Depression, Anxiety, and Stress Scales was used to assess psychiatric symptoms; and the Insomnia Severity Index was used to evaluate sleep disturbances. Risk and protective factors against burnout were assessed using a 5-point Likert scale. Results More than half of the respondents reported high graded burnout for two domains: depersonalization (50.6%) and reduced personal accomplishment (57%). Conflicts with caregivers, excessive workload, and long working hours were common risk factors for both burnout domains. The satisfaction with nonclinical work was identified as protective factor in depersonalization, and the availability of a research mentor and cap on daily inpatient load per hospitalist were protective factors in reduced personal accomplishment. In the correlation analysis, the maximum number of inpatients and hospitalists per hospital was a significant factor in reducing burnout. Conclusions This study revealed a high graded burnout rate of more than 50% in depersonalization and reduced personal accomplishments domain among Korean hospitalists, and found the risk and protective factors against burnout. The development of targeted interventions to mitigate burnout based on this study could enhance the mental well-being of healthcare professionals and improve the overall quality of medical care.