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Mineral composition and ratios in aortic valves, serum, and epicardial fat among patients with aortic stenosis undergoing aortic valve replacement
Higher-order transient structures and the principle of dynamic connectivity in membrane signaling
We examine the role of higher-order transient structures (HOTS) in M2R regulation of GIRK channels. Electron microscopic membrane protein location maps show that both proteins form HOTS that exhibit a statistical bias to be near each other. Theoretical calculations and electrophysiological measurements suggest that channel activity is isolated near larger M2R HOTS. By invoking weak interactions that permit transient binding of M2R to M2R and GIRK to GIRK ( i-i interactions) and M2R to GIRK ( i-j interactions), the distribution patterns and electrophysiological properties of HL-1 cells are replicated in a reaction-diffusion simulation. We propose the principle of dynamic connectivity to explain communication between protein components of a membrane signaling pathway. Dynamic connectivity is mediated by weak, transient interactions between proteins. HOTS created by weak i-i interactions, and statistical biases created by weak i-j interactions promoted by the multivalence of HOTS, are the key elements of dynamic connectivity.
Research on boundary control of vehicle-mounted flexible manipulator based on partial differential equations
Vehicle-mounted flexible robotic arms (VFRAs) are crucial in enhancing operational capabilities in sectors where human intervention is limited due to accessibility or safety concerns, such as hazardous environments or precision surgery. This paper introduces the latest generation of VFRAs that utilize advanced soft materials and are designed with elongated structures to provide greater flexibility and control. We present a novel mathematical model, derived using Hamilton’s principle, which simplifies the analysis of the arm’s dynamic behaviors by employing partial differential equations (PDEs). This model allows us to understand how these arms behave over time and space, classifying them as distributed parameter systems. Furthermore, we enhance the practical utility of these robotic arms by implementing a proportional-derivative (PD) based boundary control law to achieve precise control of movement and suppression of vibrations, which are critical for operations requiring high accuracy. Our approach’s effectiveness and practical utility are evidenced by numerical simulations, which verify that our advanced control strategy greatly enhances the performance and dependability of VFRAs in actual applications. These advancements not only pave the way for more sophisticated robotic implementations but also have broad implications for the future of automated systems in various industries.
Enhancing repeatability of follicle counting with deep learning reconstruction high-resolution MRI in PCOS patients
Abstract Follicle count, a pivotal metric in the adjunct diagnosis of polycystic ovary syndrome (PCOS), is often underestimated when assessed via transvaginal ultrasonography compared to MRI. Nevertheless, the repeatability of follicle counting using traditional MR images is still compromised by motion artifacts or inadequate spatial resolution. In this prospective study involving 22 PCOS patients, we employed periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) and single-shot fast spin-echo (SSFSE) T2-weighted sequences to suppress motion artifacts in high-resolution ovarian MRI. Additionally, deep learning (DL) reconstruction was utilized to compensate noise in SSFSE imaging. We compared the performance of DL reconstruction SSFSE (SSFSE-DL) images with conventional reconstruction SSFSE (SSFSE-C) and PROPELLER images in follicle detection, employing qualitative indices (blurring artifacts, subjective noise, and conspicuity of follicles) and the repeatability of follicle number per ovary (FNPO) assessment. Despite similar subjective noise between SSFSE-DL and PROPELLER as assessed by one observer, SSFSE-DL images outperformed SSFSE-C and PROPELLER images across all three qualitative indices, resulting in enhanced repeatability in FNPO assessment. These results highlighted the potential of DL reconstruction high-resolution SSFSE imaging as a more dependable method for identifying polycystic ovary, thus facilitating more accurate diagnosis of PCOS in future clinical practices.
Conservation of symbiotic signaling since the most recent common ancestor of land plants
Plants have colonized lands 450 million years ago. This terrestrialization was facilitated by developmental and functional innovations. Recent evo-devo approaches have demonstrated that one of these innovations was the mutualistic arbuscular mycorrhizal symbiosis (AMS). The genetic pathways that have been involved in the establishment and functioning of AMS since its evolution remain poorly described. Here, we found that intracellular colonization by AM fungi induces a transcriptional reporter of the common symbiosis pathway, well-described in angiosperms, in the liverwort Marchantia paleacea . Mutants of either of the three main genes of this pathway, SYMRK , CCaMK, and CYCLOPS, disrupt the ability of M. paleacea to associate with AM fungi. Finally, overexpressing gain-of-function CCaMK or CYCLOPS leads to convergent transcriptomic signatures that partially overlap with AMS. Altogether, our data indicate that plants have maintained three genes of the common symbiotic pathway to support symbiotic interactions since their most recent common ancestor.
Using the Behaviour Change Wheel to develop an intervention to improve conversations about recovery on the stroke unit
Background Understanding recovery is important for patients with stroke and their families, including how much recovery is expected and how long it might take. These conversations can however be uncomfortable for stroke unit staff, particularly when they involve breaking bad news. This study aimed to begin development of a novel complex intervention to improve conversations about recovery on stroke units. Methods Informed by previously collected qualitative data, we used the Behaviour Change Wheel (BCW) approach to identify possible 1. barriers to communication about recovery on stroke units; 2. Intervention Functions; 3. Behaviour Change Techniques (BCTs) to incorporate in an intervention. We subsequently sought stroke professionals’ perspectives through an online survey. Respondents rated the importance of barriers for intervention inclusion and evaluated the usefulness and feasibility of the suggested BCTs. Results Our behavioural diagnosis identified a target behaviour of provision of information about recovery by stroke unit professionals to patients and carers. Twelve possible barriers to this behaviour were identified, with six potential Intervention Functions to address them, and 29 BCTs. Forty-eight multidisciplinary professionals responded to the survey. The six barriers rated as most important to address were: lack of confidence; perceptions of insufficient communication skills; lack of knowledge of the benefits; difficulties in deciding when and in what format to provide information; absence of private spaces for discussions; and lack of generic written information to support conversations. The developed intervention strategy comprised twelve clinically feasible and useful BCTs, encompassing the Intervention Functions of Training, Enablement, Persuasion, and Environmental restructuring. Conclusions The BCW approach was successfully used to begin development of an intervention to improve conversations about recovery on the stroke unit; our survey enabled incorporation of stakeholder perspectives. Further development work is required to design intervention materials and test whether the strategies are effective in improving staff and patient outcomes.
Strength prediction of ECC-CES columns under eccentric compression using adaptive sampling and ML techniques
AbstractA novel type of concrete-encased steel (CES) composite column implementing Engineered Cementitious Composites (ECC) confinement (ECC-CES) has recently been introduced, offering significantly enhanced failure behavior, ductility, and toughness when compared to conventional CES columns. This study presents an innovative method for predicting the eccentric compressive capacity of ECC-CES columns, utilizing adaptive sampling and machine learning (ML) techniques. Initially, the research introduces a finite element (FE) model for ECC-CES columns, incorporating material and geometric nonlinearities to capture the inelastic behavior of both ECC and steel through appropriate constitutive material laws. The FE model was validated against experimental data, demonstrating strong predictive accuracy. An adaptive sampling process was employed to efficiently explore the design space, resulting in a database of 2,908 FE models. Subsequently, six machine learning models were used to predict the eccentric compressive capacity based on the generated FE database. These models were thoroughly evaluated and demonstrated superior prediction accuracy compared to established design standards like EC4 and AISC360. Based on evaluation metrics, the Gaussian Process Regression (GPR), CatBoost (CATB), and LightGBM (LGBM) models emerged as the most accurate and reliable, with over 97% of the finite element (FE) samples falling within a 10% error range. While the ML models demonstrate impressive performance, their black-box nature restricts their practical use in design applications. Consequently, this study introduces a proposed design that offers competitive performance metrics. The novelty of this work lies in integrating adaptive sampling through Bayesian Optimization (BO) with the power of machine learning (ML) to generate training data that effectively covers a large input space while minimizing error. SVR, CatBoost, and GPR models demonstrated mean μ, R2, and a20-index values near 1.0, with CoV and MAPE% values consistently low, indicating highly accurate predictions across testing subsets.
The carnivorous plant <i>Genlisea</i> harnesses active particle dynamics to prey on microfauna
Carnivory in plants is an unusual trait that has arisen multiple times, independently, throughout evolutionary history. Plants in the genus Genlisea are carnivorous and feed on microorganisms that live in soil using modified subterranean leaf structures (rhizophylls). A surprisingly broad array of microfauna has been observed in the plants’ digestive chambers, including ciliates, amoebae, and soil mites. Here, we show, through experiments and simulations, that Genlisea exploit active matter physics to “rectify” bacterial swimming and establish a local flux of bacteria through the structured environment of the rhizophyll toward the plant’s digestion vesicle. In contrast, macromolecular digestion products are free to diffuse away from the digestion vesicle and establish a concentration gradient of carbon sources to draw larger microorganisms further inside the plant. Our experiments and simulations show that this mechanism is likely to be a localized one and that no large-scale efflux of digested matter is present.
Parental effects provide an opportunity for coral resilience following major bleaching events
Identifying processes that promote coral reef recovery and resilience is crucial as ocean warming becomes more frequent and severe. Sexual reproduction is essential for the replenishment of coral populations and maintenance of genetic diversity; however, the ability for corals to reproduce may be impaired by marine heatwaves that cause coral bleaching. In 2014 and 2015, the Hawaiian Islands experienced coral bleaching with differential bleaching susceptibility in the species Montipora capitata, a dominant reef-building coral in the region. We tested the hypothesis that coral bleaching resistance enhances reproductive capacity and offspring performance by examining the reproductive biology of colonies that bleached and recovered (B) and colonies that did not bleach (NB) in 2015 in the subsequent spawning seasons. The proportion of colonies that spawned was higher in 2016 than in 2017. Regardless of parental bleaching history, we found eggs with higher abnormality and bundles with fewer eggs in 2016 than 2017. While reproductive output was similar between B and NB colonies in 2016, survivorship of offspring that year were significantly influenced by the parental bleaching history (egg donor × sperm donor: B × B, B × NB, NB × B, and NB × NB). Offspring produced by NB egg donors had the highest survivorship, while offspring from previously bleached colonies had the lowest survivorship, highlighting the negative effects of bleaching on parental investment and offspring performance. While sexual reproduction continues in M. capitata post-bleaching, gametes are differentially impacted by recovery time following a bleaching event and by parental bleaching resistance. Our results demonstrate the importance of identifying bleaching resistant individuals during and after heating events. This study further highlights the significance of maternal effects through potential egg provisioning for offspring survivorship and provides a baseline for human-assisted intervention (i.e., selective breeding) to mitigate the effects of climate change on coral reefs.
New fruit waste-derived activated carbons of high adsorption performance towards metal, metalloid, and polymer species in multicomponent systems
Abstract The main aim of the study was to develop new fruit waste-derived activated carbons of high adsorption performance towards metals, metalloids, and polymers by the use of carbon dioxide (CO 2 )-consuming, microwave-assisted activation. The authors compared morphology, surface chemistry, textural parameters, and elemental composition of precursors (chokeberry seeds, black currant seeds, orange peels), as well as biochars (BCs) and activated carbons (ACs) obtained from them. The adsorption mechanisms of metals (copper, cadmium), metalloids (arsenic, selenium), and macromolecular compounds (bacterial exopolysaccharide, ionic polyacrylamides) on the surface of selected materials were investigated in one- and two-component systems. Consequently, the capacities of BCs and ACs prepared through direct/indirect physical activation, using conventional/microwave heating were determined. It was noted that microwave heating favoured surface development and thus enhanced adsorbent ability to bind ions or macromolecules. Direct biomass activation led to higher microporosity compared to indirect (two-stage) one, whilst CO 2 -consuming activation increased aromaticity and hydrophobicity of the solids. In the two-component systems, polymers could favour metal/metalloid adsorption based on complexation phenomena. However, the most efficient and environmentally safe activated carbon turned out to be the one obtained from orange peels by microwave-assisted, direct activation at 800 °C in the CO 2 atmosphere.
Evolution takes multiple paths to evolvability when facing environmental change
Life at all scales is surprisingly effective at exploiting new opportunities, as demonstrated by the rapid emergence of antimicrobial resistance and novel pathogens. How populations acquire this level of evolvability and the various ways it aids survival are major open questions with direct implications for human health. Here, we use digital evolution to show that changing environments facilitate the simultaneous evolution of high mutation rates and a distribution of mutational effects skewed toward beneficial phenotypes. The evolved mutational neighborhoods allow rapid adaptation to previously encountered environments, whereas higher mutation rates aid adaptation to completely new environmental conditions. By precisely tracking evolving lineages and the phenotypes of their mutants, we show that evolving populations localize on phenotypic boundaries between distinct regions of genotype space. Our results demonstrate how evolution shapes multiple determinants of evolvability concurrently, fine-tuning a population’s adaptive responses to unpredictable or recurrent environmental shifts.
Negligible contribution of body density to in-water vertical jump performance in elite male water polo players
The aim of this study was to investigate the associations among in-water vertical jump and various dry-land physical measures by taking the law of Archimedes into consideration, and by normalizing the dry-land measures both to body density and body mass. Seventeen elite water polo players from Hungarian first league were tested for dry-land counter movement and squat jump mechanical impulse, isometric squat force, and in-water vertical jump height. Body density was estimated by anthropometric measurements. Body density alone did not influence in-water vertical jump height. Both the impulse of counter movement jump normalized to body mass (9.42±0.86 N·s/kg) and impulse of counter movement jump normalized to body density (773.92±109.68 N·s/kg/g/cm3) correlated with the in water vertical jump height (69.37±6.12 cm) (p≤0.05), but the magnitudes of the correlation coefficients 0.49 vs. 0.50 were not statistically different (p = 0.480, z = 0.04). Neither the impulse of squat jump normalized to body mass (7.07±0.59 N·s/kg) nor impulse of squat jump normalized to body density (577.87±89.16 N·s/kg/g/cm3) correlated with the in water vertical jump height (both p>0.05). The correlation between the force of the maximum voluntary isometric contraction normalized to body density (1052.13±244.65 N/kg/g/cm3) and the in water vertical jump height only approached the level of significance (p = 0.077). We concluded that dry-land reactive strength determines the ability to jump out of water, but players’ body density does not seem to contribute to jump height.
Spectral scattering characteristics of subwavelength-sized spherical particles near Mie resonance modes probed by tightly focused Terahertz waves
Dual-action kinase inhibitors influence p38α MAP kinase dephosphorylation
Reversible protein phosphorylation directs essential cellular processes including cell division, cell growth, cell death, inflammation, and differentiation. Because protein phosphorylation drives diverse diseases, kinases and phosphatases have been targets for drug discovery, with some achieving remarkable clinical success. Most protein kinases are activated by phosphorylation of their activation loops, which shifts the conformational equilibrium of the kinase toward the active state. To turn off the kinase, protein phosphatases dephosphorylate these sites, but how the conformation of the dynamic activation loop contributes to dephosphorylation was not known. To answer this, we modulated the activation loop conformational equilibrium of human p38α ΜΑP kinase with existing kinase inhibitors that bind and stabilize specific inactive activation loop conformations. From this, we identified three inhibitors that increase the rate of dephosphorylation of the activation loop phospho-threonine by the PPM serine/threonine phosphatase WIP1. Hence, these compounds are “dual-action” inhibitors that simultaneously block the active site and promote p38α dephosphorylation. Our X-ray crystal structures of phosphorylated p38α bound to the dual-action inhibitors reveal a shared flipped conformation of the activation loop with a fully accessible phospho-threonine. In contrast, our X-ray crystal structure of phosphorylated apo human p38α reveals a different activation loop conformation with an inaccessible phospho-threonine, thereby explaining the increased rate of dephosphorylation upon inhibitor binding. These findings reveal a conformational preference of phosphatases for their targets and suggest a unique approach to achieving improved potency and specificity for therapeutic kinase inhibitors.
Length of stay in the pediatrics emergency department and associated factors among pediatrics patients in Eastern Ethiopia public hospital, Ethiopia 2022
Introduction Patient length of stay is a crucial measure of the emergency department, and it is a vital indicator of health services to evaluate its efficacy, patient care, organizational management, and health care system. Despite this, there are a few studies conducted on pediatric emergency length of stay in developing countries. Therefore, this study serves as input for evidence of pediatric emergency length of stay and associated factors in public hospitals. Methods An institution-based cross-sectional study was conducted among children who attended in pediatric emergency department of Eastern Ethiopia public hospital from May 01 to Jun 31, 2022. A total of 761 children were selected by systematic sampling technique and interview using structured questionnaires. After data is collected and cleaned, entered using Epi data version 4.6 and then exported to Stata version 14.1 for analysis. Finally, an AOR with a 95% CI was computed, and variables with a P-value < 0.05 in the multivariable analysis were taken as significant factors for prolonged length of stay. Result The prevalence of prolonged length of stay in the emergency ward was 214 (72%). Living in a rural residence ([AOR = 1.65, 95% CI (1.10–2.48)], having a duration of pain > = 12 ([AOR = 1.92, 95% CI (1.13–3.25)], waiting time > = 5 minute ([AOR = 2.24, 95% CI (1.1–4.248541)], having comorbid illness ([AOR = 1.92, 95%CI, 1.13–3.25)], and higher acuity level and absence of medication in the hospital were ([AOR = 2.26, 95%CI (1.02–2.46]) were significantly associated factors for prolonged length of stay. Conclusion and recommendation This study revealed that more than two-thirds of children admitted to pediatric emergency had prolonged lengths of stay. This result indicated that higher proportion of the length of stay in pediatric emergency in Eastern Ethiopian public hospitals compare to national. Hence, it is better to give priority to strengthening the focused evaluation of important variables and manage accordingly.
A comprehensive guide to selecting suitable wavelet decomposition level and functions in discrete wavelet transform for fault detection in distribution networks
AbstractThe paper presents a comprehensive analysis of the IEEE-16 bus system under different operating conditions. It discusses the selection of suitable decomposition level and wavelet function for analyzing non-stationary signals to enhance power distribution network fault detection. MATLAB/Simulink is used to simulate the system, and transient fault current signals are processed with the MATLAB Wavelet Toolbox. The optimal decomposition level is determined by energy concentration, with the highest energy found in scales D9 (b4), D8 (b5), and D7 (b6), and D8 having the most concentration. Using MATLAB classifier learner, the article evaluates seven common mother wavelets with 53 wavelet functions, and sym3 is found to be the most efficient wavelet function in terms of training time, prediction speed, and accuracy of SVM classifiers. All fault types both symmetrical/unsymmetrical types, and various normal transient conditions such as load/capacitor/DG switching are detected/discriminated with nearly 100% accuracy at the midpoint of line 6–7 with various fault conditions, inception angles (0, 30, 45, 60, 90 and 120°) and a fault resistance of (5,10, 15, and 20 ohms). Additionally, 9 MW wind Farm is integrated at busbar 10, and various fault scenarios are simulated to assess system performance with 100% Accuracy.
Structural and functional dynamics of human cone cGMP-phosphodiesterase important for photopic vision
Cone cGMP-phosphodiesterase (PDE6) is the key effector enzyme for daylight vision, and its properties are critical for shaping distinct physiology of cone photoreceptors. We determined the structures of human cone PDE6C in various liganded states by single-particle cryo-EM that reveal essential functional dynamics and adaptations of the enzyme. Our analysis exposed the dynamic nature of PDE6C association with its regulatory γ-subunit (Pγ) which allows openings of the catalytic pocket in the absence of phototransduction signaling, thereby controlling photoreceptor noise and sensitivity. We demonstrate evolutionarily recent adaptations of PDE6C stemming from residue substitutions in the Pγ subunit and the noncatalytic cGMP binding site and influencing the Pγ dynamics in holoPDE6C. Thus, our structural analysis sheds light on the previously unrecognized molecular evolution of the effector enzyme in cones that advances adaptation for photopic vision.
Association of varicose veins with the risk of heart failure: A nationwide cohort study
Background Research investigating the association between varicose veins (VV) and heart failure has been limited. Here, we examine this association within a nationwide longitudinal cohort, hypothesizing an increased risk of heart failure associated with the presence of VV. Methods Our study included 390,436 participants based on health screening results conducted from 2005 to 2010 in the South Korean health screening cohort database. Presence of VV was defined as having at least two claims based on International Classification of Diseases, Tenth Revision (ICD-10) codes I830-832, I839, or I868. Propensity score matching (PSM) at a ratio of 1:5 was employed to categorize the participants into two groups based on the presence of VV. The primary outcome, heart failure incidence, was defined as two or more claims with ICD-10 code I50 during follow-up. Results Among the participants, presence of VV was noted in 5,008 (1.28%) individuals. Over a median follow-up period of 13.33 years (interquartile range 10.4–16.26), 55,023 cases of heart failure (14.0%) occurred. In the multivariable analysis, the group with VV consistently showed an increased incidence risk of heart failure compared to the group without VV, both before (hazard ratios [HR], 1.174; 95% confidence interval [CI], 1.089–1.265) and after PSM (HR, 1.171; 95% CI, 1.070–1.283). Landmark analysis also found a consistent relationship between the presence of VV and the incidence risk of heart failure before (HR, 1.190; 95% CI, 1.103–1.285) and after PSM (HR, 1.144; 95% CI, 1.044–1.254). Conclusions This study revealed a significant increase in the risk of heart failure among patients with VV in the general population of South Korea. Given that the presence of VV is likely associated with an increased risk of heart failure in the general population, the potential for future heart failure should be taken into consideration when VV are present.