bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and application of ZnO rod-shaped nanoparticles for the optimal operation of the plate heat exchanger
Authors: Hosseini Seyed Mohammad Sadegh , Sadeghipour Ali Mohammad , Shafiey Dehaj Mohammad
Published: September 2022

ZnO nanoparticles with tunable morphology exhibit attractive behaviors in transport phenomena, which make them valuable for thermal applications. The present study focuses on the synthesis and application of ZnO nanoparticles with two different shapes for the preparation of the working heat transfer nanofluid. First, the rod-shaped and spherical-shaped nanoparticles were synthesized by simple chemical methods and then ultrasonically dispersed in pure water to prepare a set of stable nanofluids with concentrations between 0.2% and 1% of nanoparticles. The nanofluid samples were analyzed thermo-physically to obtain the optimal nanoparticles volume fraction for presenting the best thermal properties. In the following, a brazed plate heat exchanger was examined to evaluate the heat transfer characteristics of the selected nanofluids as a coolant fluid at flow rates between 1 and 3.5 l/min. The experimental results showed that the lowest Prandtl number appeared at the volume fraction of 0.4%. This concentration was considered the operating basis of the heat exchanger. ZnO nanoparticles had the considerable effect on the thermal characteristics of water as a working fluid. The maximum growth in the heat transfer rate was found for the nanofluid with the rod-shaped nanoparticles at the lowest flow rate (1 l/min), which were 29.2% more than pure water and 7.5% higher than the nanofluid with spherical-shaped nanoparticles. Additionally, due to the exponential increase in the pumping power, there was a flow rate range (less than 2 l/min) in which the energetic performance of the nanofluids was higher than water.
Unsupervised Recognition of Informative Features via Tensor Network Machine Learning and Quantum Entanglement Variations
Authors: Bai Sheng-Chen , Tang Yi-Cheng , Ran Shi-Ju
Published: September 2022

Given an image of a white shoe drawn on a blackboard, how are the white pixels deemed (say by human minds) to be informative for recognizing the shoe without any labeling information on the pixels? Here we investigate such a “white shoe” recognition problem from the perspective of tensor network (TN) machine learning and quantum entanglement. Utilizing a generative TN that captures the probability distribution of the features as quantum amplitudes, we propose an unsupervised recognition scheme of informative features with variations of entanglement entropy (EE) caused by designed measurements. In this way, a given sample, where the values of its features are statistically meaningless, is mapped to the variations of EE that statistically characterize the gain of information. We show that the EE variations identify the features that are critical to recognize this specific sample, and the EE itself reveals the information distribution of the probabilities represented by the TN model. The signs of the variations further reveal the entanglement structures among the features. We test the validity of our scheme on a toy dataset of strip images, the MNIST dataset of hand-drawn digits, the fashion-MNIST dataset of the pictures of fashion articles, and the images of nerve cord. Our scheme opens the avenue to the quantum-inspired and interpreted unsupervised learning, which can be applied to, e.g., image segmentation and object detection.
Rotating alternating current field measurement testing system with TMR arrays for arbitrary-angle crack on nonferromagnetic pipes
Authors: Zhao Jianming , Li Wei , Yuan Xin’an , Yin Xiaokang , Ding Jianxi , Chen Qinyu , Yang Huimin
Published: September 2022

Nonferromagnetic pipes are widely used in power plants such as fluid transportation and heat exchanger devices. Due to the severity of the environments, including corrosion, high temperature, etc, they are subject to surface arbitrary-angle cracks. In view of this background, this paper proposed a rotating alternating current field measurement (RACFM) testing system for arbitrary-angle cracks on nonferromagnetic pipes. The RACFM pipe detection model is established and the unidirectional excitation coil and the orthogonal excitation coils are simulated separately. The testing system and the probe with tunnel magneto resistance sensor arrays and flexible orthogonal excitation coils are built to detect cracks at different angles on the pipe. The simulation and experimental results reveal that the RACFM detection system has high sensitivity for arbitrary-angle cracks on the outer surface of the pipe, and it can effectively measure the lengths and angles of the cracks.
Analytical approximations for the self-field distribution of a superconducting tape between iron cores
Authors: Hao Luning , Dong Fangliang , Yang Jiabin , Patel Ismail , Wei Haigening , Wang Qi , Hu Jintao , Tian Mengyuan , Shah Adil , Shen Boyang , Coombs Tim
Published: September 2022

Magnetic switches apply AC magnetic fields to DC current-carrying high temperature superconducting (HTS) tapes to generate DC voltages and are commonly used in the persistent current switches (PCSs) and flux pumps to charge HTS-coated conductor magnets. Normally, they are made of copper field coils and iron cores with narrow air gaps for the HTS tape to pass through. However, the perpendicular components of the self-field of the HTS tape in the air gap can be enhanced by the iron cores and cause a critical current reduction of up to 40% to the tape. If ignored, this reduction, rather than the magnets themselves, will limit the current carrying capability of the HTS magnets. To tackle this problem, we present analytical approximations to calculate the self-field distribution of a superconducting tape between iron cores. The approximate solutions are based on the method of images in electromagnetics to simplify the derivation and are then verified by the experiments and 3D finite element method models using the T–A formulation. The solutions are universal and can be applied to almost all the magnetic switches currently in use. A case study of typical magnetic switches shows that the solutions can be used to determine the critical current reduction quickly and accurately, analyse the influence of different parameters, and simplify the design process of magnetic switches. The results can significantly benefit the design and optimisation of PCSs and flux pumps for HTS magnet charging systems in the future.
Noisy pursuit and pattern formation of self-steering active particles
Authors: Goh Segun , Winkler Roland G , Gompper Gerhard
Published: September 2022

We consider a moving target and an active pursing agent, modeled as an intelligent active Brownian particle capable of sensing the instantaneous target location and adjusting its direction of motion accordingly. An analytical and simulation study in two spatial dimensions reveals that pursuit performance depends on the interplay between self-propulsion, active reorientation, limited maneuverability, and random noise. Noise is found to have two opposing effects: (i) it is necessary to disturb regular, quasi-elliptical orbits around the target, and (ii) slows down pursuit by increasing the traveled distance of the pursuer. For a stationary target, we predict a universal scaling behavior of the mean pursuer–target distance and of the mean first-passage time as a function of Pe2/Ω, where the Péclet number Pe characterizes the activity and Ω the maneuverability. Importantly, the scaling variable Pe2/Ω depends implicitly on the level of thermal or active noise. A similar behavior is found for a moving target, but modified by the velocity ratio α = u
0/v
0 of target and pursuer velocities u
0 and v
0, respectively. We also propose a strategy to sort active pursuers according to their motility by circular target trajectories.
Performance optimization of electret air filter
Authors: Li Xiaohui , Ma Xingchen , Chang Li , Liu Jianqing , Liao Julong , Zhang Xiaoqing
Published: September 2022

With the rapid development of the society, the severe haze weather caused by particulate matters (PMs) occurs frequently. Electret air filters have been playing an important role in purifying the air and alleviating the pollution. In this work, electret air filters were fabricated based on the polypropylene (PP) materials to investigate their filtering performance to the PMs. First, the electret performance of the PP-based films was mainly focused on. The charge storage stability of the electret films was found to be associated with the material recipe and the electret technique. Introducing 1% of tourmaline into the isotactic PP can realize the best charge storage stability, while adding the graphene can weaken the charge stability. And the electret techniques including the high-temperature pre-aging and polarization at elevated temperature were adopted to optimize the charge storage performance. Then, based on the optimized electret materials and electret technique, the purification performance of the electret filter elements dependent on the polarization condition was evaluated. The present work can provide an optimization strategy to improve the performance of electret materials and electret air filters.
Bilayer metal halide perovskite for efficient and stable solar cells and modules
Authors: Zhu Yanqing , Hu Min , Xu Mi , Zhang Bo , Huang Fuzhi , Cheng Yi-Bing , Lu Jianfeng
Published: September 2022

To reach the target of carbon neutral, a transition from fossil energy to renewable energy is unavoidable. Photovoltaic technology is considered one of the most prominent sources of renewable energy. Recently, metal halide perovskite materials have attracted tremendous interest in the areas of optoelectronic devices due to their ease of processing and outstanding performance. To date, perovskite solar cells (PSCs) have shown high power conversion efficiency up to 25.7% and 31.3% for the perovskite-silicon tandem solar cells, which promises to revolutionize the PV landscape. However, the stability of PSCs under operating conditions has yet to match state-of-the-art silicon-based solar cell technology, in which the stability of the absorbing layer and relevant interfaces is the primary challenge. These issues become more serious in the larger area solar modules due to the additional interfaces and more defects within the perovskite. Bilayer perovskite film composed of a thin low dimensional perovskite layer and a three-dimensional perovskite layer shows great potential in fabricating solar cells with high efficiency and stability simultaneously. In this review, recent advancements, including composition design and processing methods for constructing bilayer perovskite films are discussed. We then analyze the challenges and resolutions in deposition bilayer perovskite films with scalable techniques. After summarizing the beneficial effect of the bilayer structure, we propose our thinking of feasible strategies to fabricate high efficiency perovskite solar modules with a long lifetime. Finally, we outline the directions for future work that will push the perovskite PV technology toward commercialization.
Hydraulic characteristics and carbon metabolism of Haloxylon ammodendron under different water–salt content
Authors: Yang Fang , Lv Guanghui , Qie Yadong
Published: September 2022

Drought and salt stress are important abiotic stressors that adversely affect the growth, resistance and survival of plants. Haloxylon ammodendron is a strong halophyte, and its hydraulic characteristics and carbon metabolism response to drought and salt stress under natural conditions have not been widely studied. With H. ammodendron as the research object, three sample plots with different water and salt contents (high water and high salt, medium salt in reclaimed water, low water and low salt) were selected to determine their water physiology, photosynthetic physiology, carbon physiology and growth status under different water and salt conditions. Studies have shown that drought and salinity affect the hydraulic properties of H. ammodendron, reducing the water content and water potential of assimilation branches and secondary branches and increasing the hydraulic conductivity per unit cross-sectional area of biennial shoots. Affected by drought, the content of non-structural carbohydrates (NSCs) in assimilation branches and secondary branches was significantly reduced, and the NSC content of assimilating branches was significantly higher than that in secondary branches. The transportation of NSCs to the secondary branches caused obstacles, and more accumulated in the assimilating branches. In addition, drought reduced H. ammodendron photosynthesis and carbon assimilation and limited carbon uptake, resulting in slower growth. Under the influence of drought and salinity, the anisohydric properties of H. ammodendron weakened its stomatal regulation ability and made it susceptible to water transport obstacles, but the degree of carbon limitation was relatively small.
A chronotherapeutics-applicable multi-target therapeutics based on AI: Example of therapeutic hypothermia
Authors: Liu Fei , Jiang Xiangkang , Yang Jingyuan , Tao Jiawei , Zhang Mao
Published: September 2022

Nowadays, the complexity of disease mechanisms and the inadequacy of single-target therapies in restoring the biological system have inevitably instigated the strategy of multi-target therapeutics with the analysis of each target individually. However, it is not suitable for dealing with the conflicts between targets or between drugs. With the release of high-precision protein structure prediction artificial intelligence, large-scale high-precision protein structure prediction and docking have become possible. In this article, we propose a multi-target drug discovery method by the example of therapeutic hypothermia (TH). First, we performed protein structure prediction for all protein targets of each group by AlphaFold2 and RoseTTAFold. Then, QuickVina 2 is used for molecular docking between the proteins and drugs. After docking, we use PageRank to rank single drugs and drug combinations of each group. The ePharmaLib was used for predicting the side effect targets. Given the differences in the weights of different targets, the method can effectively avoid inhibiting beneficial proteins while inhibiting harmful proteins. So it could minimize the conflicts between different doses and be friendly to chronotherapeutics. Besides, this method also has potential in precision medicine for its high compatibility with bioinformatics and promotes the development of pharmacogenomics and bioinfo-pharmacology.
TPD: a web tool for tipping-point detection based on dynamic network biomarker
Authors: Chen Pei , Zhong Jiayuan , Yang Kun , Zhang Xuhang , Chen Yingqi , Liu Rui
Published: September 2022

Tipping points or critical transitions widely exist during the progression of many biological processes. It is of great importance to detect the tipping point with the measured omics data, which may be a key to achieving predictive or preventive medicine. We present the tipping point detector (TPD), a web tool for the detection of the tipping point during the dynamic process of biological systems, and further its leading molecules or network, based on the input high-dimensional time series or stage course data. With the solid theoretical background of dynamic network biomarker (DNB) and a series of computational methods for DNB detection, TPD detects the potential tipping point/critical state from the input omics data and outputs multifarious visualized results, including a suggested tipping point with a statistically significant P value, the identified key genes and their functional biological information, the dynamic change in the DNB/leading network that may drive the critical transition and the survival analysis based on DNB scores that may help to identify ‘dark’ genes (nondifferential in terms of expression but differential in terms of DNB scores). TPD fits all current browsers, such as Chrome, Firefox, Edge, Opera, Safari and Internet Explorer. TPD is freely accessible at http://www.rpcomputationalbiology.cn/TPD.
Temporal origin of mouse claustrum and development of its cortical projections
Authors: Hoerder-Suabedissen Anna , Ocana-Santero Gabriel , Draper Thomas H , Scott Sophie A , Kimani Jesse G , Shelton Andrew M , Butt Simon J B , Molnár Zoltán , Packer Adam M
Published: September 2022

The claustrum is known for its extensive connectivity with many other forebrain regions, but its elongated shape and deep location have made further study difficult. We have sought to understand when mouse claustrum neurons are born, where they are located in developing brains, and when they develop their widespread connections to the cortex. We established that a well-characterized parvalbumin plexus, which identifies the claustrum in adults, is only present from postnatal day (P) 21. A myeloarchitectonic outline of the claustrum can be derived from a triangular fiber arrangement from P15. A dense patch of Nurr1+ cells is present at its core and is already evident at birth. Bromodeoxyuridine birth dating of forebrain progenitors reveals that the majority of claustrum neurons are born during a narrow time window centered on embryonic day 12.5, which is later than the adjacent subplate and endopiriform nucleus. Retrograde tracing revealed that claustrum projections to anterior cingulate (ACA) and retrosplenial cortex (RSP) follow distinct developmental trajectories. Claustrum–ACA connectivity matures rapidly and reaches adult-like innervation density by P10, whereas claustrum–RSP innervation emerges later over a protracted time window. This work establishes the timeline of claustrum development and provides a framework for understanding how the claustrum is built and develops its unique connectivity.
Dynamic Energy Budget models: fertile ground for understanding resource allocation in plants in a changing world
Authors: Russo Sabrina E , Ledder Glenn , Muller Erik B , Nisbet Roger M
Published: September 2022

Climate change is having dramatic effects on the diversity and distribution of species. Many of these effects are mediated by how an organism’s physiological patterns of resource allocation translate into fitness through effects on growth, survival and reproduction. Empirically, resource allocation is challenging to measure directly and so has often been approached using mathematical models, such as Dynamic Energy Budget (DEB) models. The fact that all plants require a very similar set of exogenous resources, namely light, water and nutrients, integrates well with the DEB framework in which a small number of variables and processes linked through pathways represent an organism’s state as it changes through time. Most DEB theory has been developed in reference to animals and microorganisms. However, terrestrial vascular plants differ from these organisms in fundamental ways that make resource allocation, and the trade-offs and feedbacks arising from it, particularly fundamental to their life histories, but also challenging to represent using existing DEB theory. Here, we describe key features of the anatomy, morphology, physiology, biochemistry, and ecology of terrestrial vascular plants that should be considered in the development of a generic DEB model for plants. We then describe possible approaches to doing so using existing DEB theory and point out features that may require significant development for DEB theory to accommodate them. We end by presenting a generic DEB model for plants that accounts for many of these key features and describing gaps that would need to be addressed for DEB theory to predict the responses of plants to climate change. DEB models offer a powerful and generalizable framework for modelling resource allocation in terrestrial vascular plants, and our review contributes a framework for expansion and development of DEB theory to address how plants respond to anthropogenic change.
Impact of anti-arrhythmic drugs and catheter ablation on the survival of patients with atrial fibrillation: a population study based on 199 433 new-onset atrial fibrillation patients in the UK
Authors: Chung Sheng-Chia , Lai Alvina , Lip Gregory Y H , Lambiase Pier D , Providencia Rui
Published: September 2022

Aims

Utilizing real-world UK data, we aimed to understand: (i) whether anti-arrhythmic drugs and catheter ablation are effective in improving the survival of atrial fibrillation (AF) patients and (ii) which rhythm control option produces better results for the whole AF population and for specific groups of patients, stratified by age, sex, and history of heart failure.

Methods and results

We identified 199 433 individuals (mean age at diagnosis 75.7 ± 12.7 years; 50.2% women) with new-onset AF diagnosis in nationwide electronic health records linking primary care consultation with hospital data and death registry data from 1998 to 2016. We investigated the survival and causes of death of new-onset AF patients receiving vs. not-receiving rhythm control therapies. During a median follow-up of 2.7 (0.7–6.0) years, we observed a significantly lower mortality in patients receiving rhythm control [multivariate-adjusted hazard ratio (HR) = 0.86, 95% confidence interval (CI) 0.84–0.88]. Pulmonary vein isolation was associated with a two-third significant mortality reduction compared with no rhythm control (HR = 0.36, 95% CI 0.28–0.48), flecainide with 50% reduction (HR = 0.52, 95% CI 0.48–0.57), and propafenone and sotalol with reduction by a third (HR = 0.63, 95% CI 0.50–0.81, 0.71, 95% CI 0.68–0.74, respectively). Amiodarone showed no survival benefit in individuals <70 years (HR = 0.99, 95% CI 0.97–1.02). Otherwise, the effect of rhythm control on survival did not differ by age, sex, nor history of heart failure.

Conclusion

Among individuals with new-onset AF, favourable survival was observed for patients receiving rhythm control treatment. Among different rhythm control strategies, pulmonary vein isolation showed the most pronounced survival benefit.
Assessment of electrical dyssynchrony in cardiac resynchronization therapy: 12-lead electrocardiogram vs. 96-lead body surface map
Authors: Sedova Ksenia A , van Dam Peter M , Sbrollini Agnese , Burattini Laura , Necasova Lucie , Blahova Marie , Bocek Jan , Sramko Marek , Kautzner Josef
Published: September 2022

Aims

The standard deviation of activation time (SDAT) derived from body surface maps (BSMs) has been proposed as an optimal measure of electrical dyssynchrony in patients with cardiac resynchronization therapy (CRT). The goal of this study was two-fold: (i) to compare the values of SDAT in individual CRT patients with reconstructed myocardial metrics of depolarization heterogeneity using an inverse solution algorithm and (ii) to compare SDAT calculated from 96-lead BSM with a clinically easily applicable 12-lead electrocardiogram (ECG).

Methods and results

Cardiac resynchronization therapy patients with sinus rhythm and left bundle branch block at baseline (n = 19, 58% males, age 60 ± 11 years, New York Heart Association Classes II and III, QRS 167 ± 16) were studied using a 96-lead BSM. The activation time (AT) was automatically detected for each ECG lead, and SDAT was calculated using either 96 leads or standard 12 leads. Standard deviation of activation time was assessed in sinus rhythm and during six different pacing modes, including atrial pacing, sequential left or right ventricular, and biventricular pacing. Changes in SDAT calculated both from BSM and from 12-lead ECG corresponded to changes in reconstructed myocardial ATs. A high degree of reliability was found between SDAT values obtained from 12-lead ECG and BSM for different pacing modes, and the intraclass correlation coefficient varied between 0.78 and 0.96 (P < 0.001).

Conclusion

Standard deviation of activation time measurement from BSM correlated with reconstructed myocardial ATs, supporting its utility in the assessment of electrical dyssynchrony in CRT. Importantly, 12-lead ECG provided similar information as BSM. Further prospective studies are necessary to verify the clinical utility of SDAT from 12-lead ECG in larger patient cohorts, including those with ischaemic cardiomyopathy.
Rapid detection of isthmus block and rhythm change using local electrogram changes during complex atrial flutter ablation
Authors: Padanilam Benzy J , Whittam Sarah W , Clark Brad A , Olson Jeffrey A , Nair Girish V , Joshi Sandeep A , Prystowsky Eric N , Patel Parin J , Gilge Jasen L
Published: September 2022

Aims

Multiple re-entry circuits may operate simultaneously in the atria in the form of dual loop re-entry using a common isthmus, or multiple re-entrant loops without a common isthmus. When two or more re-entrant circuits coexist, ablation of an individual isthmus may lead to a seamless transition (without significant changes in surface electrocardiogram, coronary sinus activation or tachycardia cycle length) to a second rhythm, and the isthmus block can go unnoticed.

Methods and results

We hypothesize and subsequently illustrate in three patient cases, methods to rapidly identify a transition in the rhythm and isthmus block using local electrogram changes at the ablation site.

Conclusion

Local activation sequence changes, electrogram timing, and the behaviour of pre-existing double potentials can reveal isthmus block promptly when rhythm transitions occur during ablation of multiloop re-entry tachycardias.
Assessing the use of a clinical decision support tool for pain management in primary care
Authors: Apathy Nate C , Sanner Lindsey , Adams Meredith C B , Mamlin Burke W , Grout Randall W , Fortin Saura , Hillstrom Jennifer , Saha Amit , Teal Evgenia , Vest Joshua R , Menachemi Nir , Hurley Robert W , Harle Christopher A , Mazurenko Olena
Published: September 2022

Objective

Given time constraints, poorly organized information, and complex patients, primary care providers (PCPs) can benefit from clinical decision support (CDS) tools that aggregate and synthesize problem-specific patient information. First, this article describes the design and functionality of a CDS tool for chronic noncancer pain in primary care. Second, we report on the retrospective analysis of real-world usage of the tool in the context of a pragmatic trial.

Materials and methods

The tool known as OneSheet was developed using user-centered principles and built in the Epic electronic health record (EHR) of 2 health systems. For each relevant patient, OneSheet presents pertinent information in a single EHR view to assist PCPs in completing guideline-recommended opioid risk mitigation tasks, review previous and current patient treatments, view patient-reported pain, physical function, and pain-related goals.

Results

Overall, 69 PCPs accessed OneSheet 2411 times (since November 2020). PCP use of OneSheet varied significantly by provider and was highly skewed (site 1: median accesses per provider: 17 [interquartile range (IQR) 9–32]; site 2: median: 8 [IQR 5–16]). Seven “power users” accounted for 70% of the overall access instances across both sites. OneSheet has been accessed an average of 20 times weekly between the 2 sites.

Discussion

Modest OneSheet use was observed relative to the number of eligible patients seen with chronic pain.

Conclusions

Organizations implementing CDS tools are likely to see considerable provider-level variation in usage, suggesting that CDS tools may vary in their utility across PCPs, even for the same condition, because of differences in provider and care team workflows.
Natural borneol enhances the anti-cerebral ischaemia efficacy of formononetin in MCAO/R rats by promoting its delivery in the brain
Authors: Li Jia-Yu , Wang Jin-Xin , Li Qiu-Hao , Li Xiao-Feng , Xiao Jun-Ping , Li Shan-Shan , Shen Xiu-Ping , Zhang Wei-Dong , Shen Yun-Heng
Published: September 2022

Objectives Due to its high morbidity, high mortality, and high disability, stroke has been the first cause of death and the major cause of adult disability in China. Natural borneol has been widely utilized in Traditional Chinese Medicine to promote drug absorption. Formononetin is a natural isoflavonoid with potent neuroprotective activity but poor brain delivery.

Methods This study aimed to screen the optimum proportion that natural borneol promotes formononetin entry into the brain, evaluate the anti-cerebral ischaemia efficacy of formononetin/natural borneol combination in middle cerebral artery occlusion/reperfusion model rats, and clarify the possible mechanism for natural borneol’s promoting formononetin delivery in the brain.

Key findings Our studies exhibited that natural borneol remarkably promoted formononetin entry into the brain when combined with formononetin in a 1 : 1 molar ratio and notably improved neuro-behavioural scores and reduced the infarct of middle cerebral artery occlusion/reperfusion model rats. This study further discovered that the enhanced anti-cerebral ischaemia effect resulted from natural borneol increasing the permeability of the blood-brain barrier to elevate formononetin concentration in the brain rather than the pharmacodynamic synergy or addition between formononetin and natural borneol.

Conclusions The study provides a good strategy to screen drug combinations for the treatment of brain disease by combining natural borneol with other drugs.
An exploration of the properties of cluster profiles for the thermal and kinetic Sunyaev–Zel’dovich effects
Authors: Lee Billy K K , Coulton William R , Thiele Leander , Ho Shirley
Published: September 2022

With the advent of high-resolution, low-noise CMB measurements, the ability to extract cosmological information from thermal Sunyaev–Zel’dovich effect and kinetic Sunyaev–Zel’dovich effect will be limited not by statistical uncertainties but rather by systematic and theoretical uncertainties. The theoretical uncertainty is driven by the lack of knowledge about the electron pressure and density. Thus, we explore the electron pressure and density distributions in the IllustrisTNG hydrodynamical simulations, and we demonstrate that the cluster properties exhibit a strong dependence on the halo concentration – providing some of the first evidence of cluster assembly bias in the electron pressure and density. Further, our work shows evidence for a broken power-law mass dependence, with lower pressure in lower mass haloes than previous work and a strong evolution with mass of the radial correlations in the electron density and pressure. Both of these effects highlight the differing impact of active galactic nuclei and supernova feedback on the gas in galaxy groups compared to massive clusters. We verified that we see qualitatively similar features in the SIMBA hydrodynamical simulations, suggesting these effects could be generic features. Finally, we provide a parametric formula for the electron pressure and density profile as a function of dark matter halo mass, halo concentration, and redshift. Despite our extensions, the best-fitting formulae are not able to fully capture the features seen in certain mass, radius, and redshift regimes, thereby highlighting the challenges of precision modelling gas profiles.
Double-strand break toxicity is chromatin context independent
Authors: Friskes Anoek , Koob Lisa , Krenning Lenno , Severson Tesa M , Koeleman Emma S , Vergara Xabier , Schubert Michael , van den Berg Jeroen , Evers Bastiaan , Manjón Anna G , Joosten Stacey , Kim Yongsoo , Zwart Wilbert , Medema René H
Published: September 2022

Cells respond to double-strand breaks (DSBs) by activating DNA damage response pathways, including cell cycle arrest. We have previously shown that a single double-strand break generated via CRISPR/Cas9 is sufficient to delay cell cycle progression and compromise cell viability. However, we also found that the cellular response to DSBs can vary, independent of the number of lesions. This implies that not all DSBs are equally toxic, and raises the question if the location of a single double-strand break could influence its toxicity. To systematically investigate if DSB-location is a determinant of toxicity we performed a CRISPR/Cas9 screen targeting 6237 single sites in the human genome. Next, we developed a data-driven framework to design CRISPR/Cas9 sgRNA (crRNA) pools targeting specific chromatin features. The chromatin context was defined using ChromHMM states, Lamin-B1 DAM-iD, DNAseI hypersensitivity, and RNA-sequencing data. We computationally designed 6 distinct crRNA pools, each containing 10 crRNAs targeting the same chromatin state. We show that the toxicity of a DSB is highly similar across the different ChromHMM states. Rather, we find that the major determinants of toxicity of a sgRNA are cutting efficiency and off-target effects. Thus, chromatin features have little to no effect on the toxicity of a single CRISPR/Cas9-induced DSB.
Correlation of SARS-CoV-2 Nasopharyngeal CT Values With Viremia and Mortality in Adults Hospitalized With COVID-19
Authors: Hagman Karl , Hedenstierna Magnus , Widaeus Jacob , Arvidsson Emelie , Hammas Berit , Grillner Lena , Jakobsson Jan , Gille-Johnson Patrik , Ursing Johan
Published: September 2022

Background

Both severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viremia and nasopharyngeal viral load have been suggested to be predictors of unfavorable outcome in coronavirus disease 2019 (COVID-19). This study aimed to investigate whether nasopharyngeal viral load is correlated with viremia and unfavorable outcome.

Methods

The presence of SARS-CoV-2 RNA was determined in paired nasopharyngeal and serum samples collected at admission from patients hospitalized for COVID-19. Standardized cycle threshold values (CT values) were used as an indicator of viral load. An adjusted logistic regression was used to estimate the risk of viremia at different nasopharyngeal CT values. A Cox regression was used to estimate the risk of 60-day mortality.

Results

A total of 688 patients were included. Viremia at admission was detected in 63% (146/230), 46% (105/226), and 31% (73/232) of patients with low, intermediate, and high nasopharyngeal CT values. The adjusted odds ratios of being viremic were 4.4 (95% CI, 2.9–6.8) and 2.0 (95% CI, 1.4–3.0) for patients with low and intermediate CT values, compared with high CT values. The 60-day mortality rate was 37% (84/230), 15% (36/226), and 10% (23/232) for patients with low, intermediate, and high nasopharyngeal CT values at admission, respectively. Adjusted hazard ratios were 2.6 (95% CI, 1.6–4.2) and 1.4 (95% CI, 0.8–2.4) for patients with low and intermediate CT values compared with high CT values.

Conclusions

There was a dose-dependent correlation between nasopharyngeal CT values and viremia at admission for COVID-19. Moreover, there was an increased risk of 60-day mortality for patients with low, compared with high, nasopharyngeal CT values.
Insights into the molecular mechanisms of CRISPR/Cas9-mediated gene targeting at multiple loci in Arabidopsis
Authors: Zhang Zhengjing , Zeng Wenjie , Zhang Wenxin , Li Jing , Kong Dali , Zhang Lei , Wang Rui , Peng Fangnan , Kong Zhe , Ke Yongping , Zhang Heng , Kim Chanhong , Zhang Huiming , Botella Jose Ramón , Zhu Jian-Kang , Miki Daisuke
Published: September 2022

Homologous recombination-mediated gene targeting (GT) enables precise sequence knockin or sequence replacement, and thus is a powerful tool for heritable precision genome engineering. We recently established a clustered regularly interspaced short palindromic repeats/clustered regularly interspaced short palindromic repeats-associated protein 9 (CRISPR/Cas9)-mediated approach for heritable GT in Arabidopsis (Arabidopsis thaliana), but its broad utility was not tested, and the underlying molecular mechanism was unclear. Here, we achieved precise GT at 14 out of 27 tested endogenous target loci using the sequential transformation approach and obtained vector-free GT plants by backcrossing. Thus, the sequential transformation GT method provides a broadly applicable technology for precise genome manipulation. We show that our approach generates heritable GT in the egg cell or early embryo of T1 Arabidopsis plants. Analysis of imprecise GT events suggested that single-stranded transfer DNA (T-DNA)/VirD2 complexes produced during the Agrobacterium (Agrobacterium tumefaciens) transformation process may serve as the donor templates for homologous recombination-mediated repair in the GT process. This study provides new insights into the molecular mechanisms of CRISPR/Cas9-mediated GT in Arabidopsis.
Evaluating the Effectiveness of Joint Specialist Case Conferences in Improving Diabetes Control in Patients With Schizophrenia on Clozapine
Authors: Zheng Yu , Meyerowitz-Katz Gideon , Bramwell Sian , Jayaballa Rajini , Assur Yolinda , Vasani Deepali , Ganapathy Ramanathan , Maberly Glen , Brakoulias Vlasios
Published: September 2022

Clozapine treatment for schizophrenia is typically long-term and is associated with a high rate of diabetes. Mental health and diabetes specialist teams at a local hospital in Australia have undertaken a series of joint specialist case conferences (JSCCs) where the diabetes team works with the psychiatry team to improve diabetes management. In this retrospective cohort study conducted between 2013 and 2018, we found that glycemic control in clozapine clinics linked with JSCCs was improved significantly compared with that in the non-JSCC clinics. In the non-JSCC clozapine clinics (control), the poor glycemic control rates stayed at a similar level: 23% in 2013 and 24% in 2018. In contrast, whereas the control patients' poor glycemic rate in JSCC clozapine clinics in 2013 was 24%, it decreased markedly in 2018 to 13%. This study indicates that JSCCs can improve diabetes outcomes in a group of patients with severe mental illness.
Effect of Plasma Resuscitation with Adjunctive Peritoneal Resuscitation on Hepatic Blood Flow and End-Organ Damage after Hemorrhagic Shock
Authors: Smith Jason W , Schucht Jessica E , Harbrecht Brian G , Bond Logan M , Matheson Paul J
Published: September 2022

BACKGROUND:

Intestinal injury from resuscitated hemorrhagic shock (HS) disrupts intestinal microvascular flow and causes enterocyte apoptosis, intestinal barrier breakdown, and injury to multiple organs. Fresh frozen plasma (FFP) resuscitation or directed peritoneal (DPR) resuscitation protect endothelial glycocalyx, improve intestinal blood flow, and alleviate intestinal injury. We postulated that FFP plus DPR might improve effective hepatic blood flow (EHBF) and prevent associated organ injury (liver, heart).

STUDY DESIGN:

Anesthetized Sprague-Dawley rats underwent HS (40% mean arterial pressure, 60 minutes) and were randomly assigned to groups (n = 8 per group): Sham; crystalloid resuscitation (CR; shed blood + 2 volumes CR); DPR (intraperitoneal 2.5% peritoneal dialysis fluid); FFP (shed blood + 1 vol IV FFP); FFP + DPR. EHBF was measured at postresuscitation timepoints. Organ injury was evaluated by serum ELISA (fatty acid-binding protein [FABP]-1 [liver], FABP-3 [heart], Troponin-I [heart], and Troponin-C [heart]) and hematoxylin and eosin. Differences were evaluated by 1-way ANOVA and 2-way repeated-measures ANOVA.

RESULTS:

CR resuscitation alone did not sustain EHBF. FFP resuscitation restored EHBF after resuscitation (2 hours, 3 hours, and 4 hours). DPR resuscitation restored EHBF throughout the postresuscitation period but failed to restore serum FABP-1 VS other groups. Combination FFP + DPR rapidly and sustainably restored EHBF and decreased organ injury. CR and DPR alone had elevated organ injury (FABP-1 [hepatocyte], FABP-3 [cardiac], and Troponin-I/C), whereas FFP or FFP + DPR demonstrated reduced injury at 4 hours after resuscitation.

CONCLUSION:

HS decreased EHBF, hepatocyte injury, and cardiac injury as evidenced by serology. FFP resuscitation improved EHBF and decreased organ damage. Although DPR resuscitation resulted in sustained EHBF, this alone failed to decrease hepatocyte or cardiac injury. Combination therapy with DPR and FFP may be a novel method to improve intestinal and hepatic blood flow and decrease organ injury after HS/resuscitation.
Observation of anomalous spectral downshifting of waves in the Okhotsk Sea Marginal Ice Zone
Authors: Waseda Takuji , Alberello Alberto , Nose Takehiko , Toyota Takenobu , Kodaira Tsubasa , Fujiwara Yasushi
Published: September 2022

Waves in the Marginal Ice Zone in the Okhotsk Sea are less studied compared to the Antarctic and Arctic. In February 2020, wave observations were conducted for the first time in the Okhotsk Sea, during the observational program by Patrol Vessel Soya. A wave buoy was deployed on the ice, and
in situ
wave observations were made by a ship-borne stereo imaging system and Inertial Measurement Unit. Sea ice was observed visually and by aerial photographs by drone, while satellite synthetic aperture radar provided basin-wide spatial distribution. On 12 February, a swell system propagating from east northeast was detected by both the stereo imaging system and the buoy-on-ice. The wave system attenuated from 0.34 m significant wave height to 0.25 m in about 90 km, while the wave period increased from 10 s to 15–17 s. This anomalous spectral downshifting was not reproduced by numerical hindcast and by applying conventional frequency-dependent exponential attenuation to the incoming frequency spectrum. The estimated rate of spectral downshifting, defined as a ratio of momentum and energy losses, was close to that of uni-directional wave evolution accompanied by breaking dissipation: this indicates that dissipation-driven nonlinear downshifting may be at work for waves propagating in ice.

This article is part of the theme issue 'Theory, modelling and observations of marginal ice zone dynamics: multidisciplinary perspectives and outlooks'.
Theoretical framework for the emergent floe size distribution in the marginal ice zone: the case for log-normality
Authors: Montiel Fabien , Mokus Nicolas
Published: September 2022

Sea ice is not horizontally homogeneous on large scales. Its morphology is inherently discrete and made of individual floes. In recent years, sea ice models have incorporated this horizontal heterogeneity. The modelling framework considers an evolution equation for the probability density function of the floe size distribution (FSD) with forcing terms that represent the effects of several physical processes. Despite the modelling effort, a key question remains: What is the FSD emerging from the collection of all forcing processes? Field observations have long suggested that the FSD follows a power law, but this result has not been reproduced by models or laboratory experiments. The theoretical framework for FSD dynamics in response to physical forcings is presented. Wave-induced breakup is further examined with an emphasis on how it affects the FSD. Recent modelling results suggesting the consistent emergence of a log-normal distribution as a result of that process are further discussed. Log-normality is also found in a dataset of floe sizes, which was originally analysed under the power law hypothesis. A simple stochastic process of FSD dynamics, based on random fragmentation theory, is further shown to predict log-normality. We therefore conjecture that, in some situations, the emergent FSD follows a log-normal distribution.

This article is part of the theme issue ‘Theory, modelling and observations of marginal ice zone dynamics: multidisciplinary perspectives and outlooks’.
Multi-scale satellite observations of Arctic sea ice: new insight into the life cycle of the floe size distribution
Authors: Hwang Byongjun , Wang Yanan
Published: September 2022

This study provides a new conceptional framework to understand the life cycle of the floe size distribution of Arctic sea ice and the associated processes. We derived the floe size distribution from selected multi-scale satellite imagery data acquired from different locations and times in the Arctic. Our study identifies three stages of the floe size evolution during summer – ‘fracturing’, ‘transition’ and ‘melt/wave fragmentation’. Fracturing defines the initial floe size distribution (
N
 ∼ 

d
−α

, where
d
is floe size) formed from the spring breakup, characterized by the single power-law regime over
d
 = 30–3000 m with
α
 

≈

 2. The initial floe size distribution is then modified by various floe fragmentation processes during the transition period, which is characterized by ‘selective’ fragmentation of large floes (
d
 > 200–300 m) with variable
α
 = 2.5–3.5 depending on the degree of fragmentation. As ice melt intensifies, the melt fragmentation expands the single power-law regime into smaller floes (
d
 = 70 m) with
α
 = 2.4–3.8, while a significant reduction of small floes (
d
 < 30–40 m) occurs due to lateral melt. The shape factor shows an overall progression from elongated floes into rounded floes. The effects of scaling and wave-fracture are also discussed.

This article is part of the theme issue 'Theory, modelling and observations of marginal ice zone dynamics: multidisciplinary perspectives and outlooks'.
Granular effects in sea ice rheology in the marginal ice zone
Authors: Herman A.
Published: September 2022

Sea ice in the marginal ice zone (MIZ) consists of relatively small floes with a wide size span. In response to oceanic and atmospheric forcing, it behaves as an approximately two-dimensional, highly polydisperse granular material. The established viscous-plastic rheologies used in continuum sea ice models are not suitable for the MIZ; the collisional rheology, in which sea ice is treated as a granular gas, captures only one aspect of the granular behaviour, typical for a narrow range of conditions when dynamics is dominated by binary floe collisions. This paper reviews rheology models and concepts from research on granular materials relevant for MIZ dynamics (average stress as a result of ‘microscopic’ interactions of grains;

μ
(
I
)

and collisional rheologies). Idealized discrete-element simulations are used to illustrate granular effects and strong influence of the floe size distribution on strain–stress relationships in sheared sea ice, demonstrating the need for an MIZ rheology model capturing the whole range of ‘regimes’, from quasi-static/dense flow in the inner MIZ to the inertial flow in the outer MIZ.

This article is part of the theme issue ‘Theory, modelling and observations of marginal ice zone dynamics: multidisciplinary perspectives and outlooks’.
A model study of convergent dynamics in the marginal ice zone
Authors: Auclair Jean-Pierre , Dumont Dany , Lemieux Jean-François , Ritchie Hal
Published: September 2022

With the increasing resolution of operational forecasting models, the marginal ice zone (MIZ), the area where waves and sea ice interact, can now be better represented. However, the proper mechanics of wave propagation and attenuation in ice, and especially their influence on sea ice dynamics, still remain poorly understood and constrained in models. Observations have shown exponential wave energy decrease with distance in sea ice, particularly strong at higher frequencies. Some of this energy is transferred to the ice, breaking it into smaller floes and weakening it, as well as exerting a stress on the ice similar to winds and currents. In this article, we present a one-dimensional, fully integrated wave and ice model that has been developed to test different parameterizations of wave–ice interactions. The response of the ice cover to the wind and wave radiative stresses is investigated for a variety of wind, wave and ice conditions at different scales. Results of sensitivity analyses reveal the complex interplay between wave attenuation and rheological parameters and suggest that the compressive strength of the MIZ may be better represented by a Mohr-Coulomb parameterization with a nonlinear dependence on thickness.

This article is part of the theme issue ‘Theory, modelling and observations of marginal ice zone dynamics: multidisciplinary perspectives and outlooks’.