bluuebunny/crossref_metadata_2025 huggingface dataset:
Chaotic dynamics in refraction galactic billiards
Authors: Barutello Vivina L , De Blasi Irene , Terracini Susanna
Published: June 2023

We prove the presence of topological chaos at high internal energies for a new class of mechanical refraction billiards coming from Celestial Mechanics. Given an open and bounded domainD∈R2with smooth boundary, a central mass generates a Keplerian potential in it, while, inR2∖D‾, a harmonic oscillator-type potential acts. At the interface, Snell’s law of refraction holds. The chaoticity result is obtained by imposing progressive assumptions on the domain, arriving to geometric conditions which holds generically in. The workflow starts with the existence of a symbolic dynamics and ends with the proof of topological chaos. Intermediate results will be the analytic non-integrability and the presence of multiple heteroclinic connections between different equilibrium saddle points. This work can be considered as the final step of the investigation carried on in De Blasi and Terracini (2022Nonlinear Anal.218112766; 2023Discrete Contin. Dyn. Syst.431269–318).
Human-sized quantitative imaging of magnetic nanoparticles with nonlinear magnetorelaxometry
Authors: Schier Peter , Jaufenthaler Aaron , Liebl Maik , Arsalani Soudabeh , Wiekhorst Frank , Baumgarten Daniel
Published: June 2023

Objective. Magnetorelaxomety imaging (MRXI) is a noninvasive imaging technique for quantitative detection of magnetic nanoparticles (MNPs). The qualitative and quantitative knowledge of the MNP distribution inside the body is a prerequisite for a number of arising biomedical applications, such as magnetic drug targeting and magnetic hyperthermia therapy. It was shown throughout numerous studies that MRXI is able to successfully localize and quantify MNP ensembles in volumes up to the size of a human head. However, deeper regions that lie far from the excitation coils and the magnetic sensors are harder to reconstruct due to the weaker signals from the MNPs in these areas. On the one hand, stronger magnetic fields need to be applied to produce measurable signals from such MNP distributions to further upscale MRXI, on the other hand, this invalidates the assumption of a linear relation between applied magnetic field and particle magnetization in the current MRXI forward model which is required for the imaging procedure. Approach. We tackle this problem by introducing a nonlinear MRXI forward model that is also valid for strong magnetic excitation fields. Main results. We demonstrate in our experimental feasibility study that scaling up the imaging region to the size of a human torso using nonlinear MRXI is possible. Despite the extreme simplicity of the imaging setup applied in this study, an immobilized MNP sample with 6.3 cm3 and 12 mg Fe could be localized and quantified with an acceptable quality. Significance. A well-engineered MRXI setup could provide much better imaging qualities in shorter data acquisition times, making nonlinear MRXI a viable option for the supervision of MNP related therapies in all regions of the human body, specifically magnetic hyperthermia.
Graph ‘texture’ features as novel metrics that can summarize complex biological graphs
Authors: Barker-Clarke R , Weaver D T , Scott J G
Published: June 2023

Objective. Image texture features, such as those derived by Haralick et al, are a powerful metric for image classification and are used across fields including cancer research. Our aim is to demonstrate how analogous texture features can be derived for graphs and networks. We also aim to illustrate how these new metrics summarize graphs, may aid comparative graph studies, may help classify biological graphs, and might assist in detecting dysregulation in cancer. Approach. We generate the first analogies of image texture for graphs and networks. Co-occurrence matrices for graphs are generated by summing over all pairs of neighboring nodes in the graph. We generate metrics for fitness landscapes, gene co-expression and regulatory networks, and protein interaction networks. To assess metric sensitivity we varied discretization parameters and noise. To examine these metrics in the cancer context we compare metrics for both simulated and publicly available experimental gene expression and build random forest classifiers for cancer cell lineage. Main results. Our novel graph ‘texture’ features are shown to be informative of graph structure and node label distributions. The metrics are sensitive to discretization parameters and noise in node labels. We demonstrate that graph texture features vary across different biological graph topologies and node labelings. We show how our texture metrics can be used to classify cell line expression by lineage, demonstrating classifiers with 82% and 89% accuracy. Significance. New metrics provide opportunities for better comparative analyzes and new models for classification. Our texture features are novel second-order graph features for networks or graphs with ordered node labels. In the complex cancer informatics setting, evolutionary analyses and drug response prediction are two examples where new network science approaches like this may prove fruitful.
Dosimetric comparison of autocontouring techniques for online adaptive proton therapy
Authors: Smolders A , Choulilitsa E , Czerska K , Bizzocchi N , Krcek R , Lomax A , Weber D C , Albertini F
Published: June 2023

Objective. Anatomical and daily set-up uncertainties impede high precision delivery of proton therapy. With online adaptation, the daily plan is reoptimized on an image taken shortly before the treatment, reducing these uncertainties and, hence, allowing a more accurate delivery. This reoptimization requires target and organs-at-risk (OAR) contours on the daily image, which need to be delineated automatically since manual contouring is too slow. Whereas multiple methods for autocontouring exist, none of them are fully accurate, which affects the daily dose. This work aims to quantify the magnitude of this dosimetric effect for four contouring techniques. Approach. Plans reoptimized on automatic contours are compared with plans reoptimized on manual contours. The methods include rigid and deformable registration (DIR), deep-learning based segmentation and patient-specific segmentation. Main results. It was found that independently of the contouring method, the dosimetric influence of using automatic OAR contours is small (<5% prescribed dose in most cases), with DIR yielding the best results. Contrarily, the dosimetric effect of using the automatic target contour was larger (>5% prescribed dose in most cases), indicating that manual verification of that contour remains necessary. However, when compared to non-adaptive therapy, the dose differences caused by automatically contouring the target were small and target coverage was improved, especially for DIR. Significance. The results show that manual adjustment of OARs is rarely necessary and that several autocontouring techniques are directly usable. Contrarily, manual adjustment of the target is important. This allows prioritizing tasks during time-critical online adaptive proton therapy and therefore supports its further clinical implementation.
Phase-tunable multiple Andreev reflections in a quantum spin Hall strip
Authors: Yang Xue , Burset Pablo , Lu Bo
Published: June 2023

A quantum spin Hall strip where different edges are contacted by s-wave superconductors with a phase difference φ supports Majorana bound states protected by time-reversal symmetry. We study signatures of these states in a four-terminal setup where two Josephson junctions are built on opposite edges of the strip and the phase difference between superconductors can be controlled by an external flux. Applying a voltage bias across the quantum spin Hall strip results in a sequence of conductance peaks from multiple Andreev reflections (MARs). We find that this so-called subharmonic gap structure is very sensitive to the phase difference and displays a phase-controlled even–odd effect, where all odd spikes disappear when the Majorana states are formed for

ϕ
=
π

. Moreover, the remaining even spikes split when the superconductors forming the junction have different gap size. We explain these features by showing that any midgap bound states enhance the transmission of the even order MARs, while the reduced density of states at the gap edges suppresses the odd order ones.
Coherent population transfer in the interaction of five-state nuclei with x-ray lasers using chain-STIRAP technique
Authors: Amiri Mehdi , Saadati-Niari Maghsoud
Published: June 2023

The complete population transfer from the first state to the fifth one in a five-state nuclear system that interacts with four x-ray laser pulses has been theoretically studied using the chain-STIRAP technique. In this scheme, it is assumed that the accelerated nucleus interacts with four x-ray laser pulses, and the relativistic factor is adjusted so that the resonance condition is established between the x-ray laser frequencies and the transition frequency of the nucleus. In this study, by establishing the adiabatic condition, the Hamiltonian of the system remains in the dark state. Therefore, the second and fourth states are not populated during the time evolution. Also, to eliminate the population of the third state during the interaction, the middle pulses are considered more significant compared to the first and last pulses. For the numerical study, 168Er is considered and, it is shown that the population is completely transferred from the first state to the fifth state.
Reconstructing the cosmological density and velocity fields from redshifted galaxy distributions using V-net
Authors: Qin Fei , Parkinson David , Hong Sungwook E. , Sabiu Cristiano G.
Published: June 2023

The distribution of matter that is measured through galaxy redshift and peculiar velocity surveys can be harnessed to learn about the physics of dark matter, dark energy, and the nature of gravity. To improve our understanding of the matter of the Universe, we can reconstruct the full density and velocity fields from the galaxies that act as tracer particles. In this paper, we use
the simulated halos as proxies for the galaxies. We use a convolutional neural network, a V-net, trained on numerical simulations of structure formation to reconstruct the density and velocity fields. We find that, with detailed tuning of the loss function, the V-net could produce better fits to the density field in the high-density and low-density regions, and improved predictions for the probability distribution of the amplitudes of the velocities. However, the weights will reduce the precision of the estimated β parameter. We also find that the redshift-space distortions of the halo catalogue do not significantly contaminate the reconstructed real-space density and velocity field. We estimate the velocity field β parameter by comparing the peculiar velocities of halo catalogues to the reconstructed velocity fields, and find the estimated β values agree with the fiducial value at the 68% confidence level.
Low-power blue LED and red laser effects on plasmid DNA, survival, and photolyase mRNA levels in Escherichia coli cultures
Authors: Ribeiro Rickson Souza , Rodrigues Juliana Alves , Mencalha Andre Luiz , da Fonseca Adenilson de Souza
Published: June 2023

Low-power lasers and light-emitting diodes (LEDs) are used for photobiomodulation therapy, but the photobiological effects on DNA repair mechanisms in bacteria cells are disputed yet. This work aimed to evaluate the induction of DNA damages in plasmids, bacterial survival and proliferation, and photolyase mRNA levels in E. coli cultures exposed to low-power blue LED and red laser, followed by ultraviolet c (UVC) radiation. Aliquots of pUC19 plasmids and E. coli C600 cultures were exposed to low-power blue LED (470 nm) and red laser (658 nm) at different fluences. Other E. coli C600 cultures were exposed to UVC radiation after exposure to low-power blue LED and red laser. After irradiations, plasmids were submitted to agarose gel electrophoresis to evaluate DNA damage, bacterial cultures were spread onto Petri dishes content rich medium and incubated to evaluate bacterial survival and proliferation, and photolyase mRNA levels in bacterial cells were evaluated by reverse transcription-quantitative polymerase chain reaction. The results suggest that exposure to blue and red lights emitted from low-power LEDs and lasers does not cause DNA strand breaks in bacterial plasmids and does not alter the survival and mRNA levels from photolyase gene in E. coli cells, but increases bacterial survival and proliferation in E. coli cultures exposed to UVC radiation depending on LED and laser fluences.
Disruption prediction on EAST with different wall conditions based on a multi-scale deep hybrid neural network
Authors: Guo B.H. , Chen D.L. , Rea C. , Wu M.Q. , Shen B. , Granetz R.S. , Zhang Z.C. , Huang Y. , Duan Y.M. , Zeng L. , Xiao B.J.
Published: June 2023

Plasma disruption is a very dangerous event for future tokamaks and fusion reactors. Therefore, predicting disruption is crucial for ensuring the safety and performance of reactors. In this study, the features of two deep learning algorithms are integrated to establish a multi-scale hybrid network disruption predictor. Firstly, 43 diagnostic signals are extracted by a convolutional neural network (CNN), and the time information is learned by a long short-term memory network. The predictor is trained and tested on a database containing

∼

10
4

non-all-metal wall discharges. Its area under the receiver operator characteristic curve (AUC), which is a common performance metric for deep learning algorithms, reaches 0.97, and the true positive rate is

∼

95.3
%

, while the false positive rate is

∼

8
%

. Since EAST was upgraded in 2020, the wall condition has been upgraded from non-all-metal to all-metal. To examine the robustness of the predictor, the EAST disruption predictor is migrated to the all-metal wall experiment for the first time. It is again tested under the all-metal wall experimental data, and its warning performance decreases significantly, with an AUC of only 0.79. To improve the robustness and sensitivity of the predictor against disruptions, the convolutional attention mechanism is introduced into the CNN. After training and testing with the same data set, the warning performance for the all-metal wall data is improved, with the AUC value increasing to 0.84. To further improve the robustness of the predictor, the t-distributed stochastic neighbor embedding algorithm is employed to explore the difference of the sample distribution before and after EAST upgradation, and the transfer learning algorithm is used to reduce this difference. By applying transfer learning to a small amount of discharges from the all-metal wall data, the warning performance in the all-metal wall experiment is further improved, and the AUC value increases to 0.93. Overall, the proposed data-driven predictor is promising for applications in future devices such as ITER.
The phase-space structure of a nonlinear ion diffusion tensor in ion-temperature-gradient-driven turbulence
Authors: Sun Shiqiao , Li Yuesong , Wang Zihao , Wang Shaojie
Published: June 2023

The phase-space structure of an ion diffusion tensor in ion temperature gradient (ITG)-driven turbulence is studied using the newly developed numerical code Numerical Diagnosis of Transport Matrix. The numerical results show that at both the linear and nonlinear stage, the diffusion tensor of ITG turbulence presents a typical ballooning structure in the poloidal direction and a magnetic drift resonance structure in velocity space. The D

rr
and D

rK
components of the diffusion tensor satisfy the Stokes–Einstein relation. It is found that the phase-space structure of the ion diffusion tensor at the linear stage is induced by the resonance between ions and ITG eigenmodes, while that at the nonlinear stage is induced by the resonance between ions and the daughter ballooning modes under the poloidal acceleration of nonlinear zonal radial electric fields.
Neon seeding effects on two high-performance baseline plasmas on the Joint European Torus
Authors: Gabriellini S. , Garzotti L. , Zotta V.K. , Bourdelle C. , Casson F.J. , Citrin J. , Frigione D. , Gatto R. , Giroud C. , Koechl F. , Lomas P. , Marin M. , Menmuir S. , Pucella G. , Rimini F. , van Eester D.
Published: June 2023

We present the JETTO-QuaLiKiz-SANCO fully predictive modelling of two JET-ILW high-performance baseline plasmas, a Ne seeded shot and an equivalent unseeded one. The motivation of the work lies in the experimental observation of a slightly higher confinement and performance of the Ne seeded shot with respect to the unseeded one, despite sharing the same main plasma parameters and heating powers. Moreover, the neon seeded shot shows a lower pedestal electron density and a higher core ion temperature with respect to the unseeded one. Integrated modelling is performed in order to understand if the cause of the improved confinement has to be ascribed to the improved pedestal parameters with neon seeding or if an impurity-induced turbulence stabilization is at play. The QuaLiKiz transport model is used for predicting the electron density, electron and ion temperatures and rotation in the core up to the pedestal top, while the pedestal is empirically modelled to reproduce the experimental kinetic profiles. The thermal diffusivities of the two shots, computed by QuaLiKiz, are compared, as well as the turbulence spectra, suggesting that the reduced transport found in the neon seeded shot is due in part to the stabilization of ion temperature gradient and electron temperature gradient modes. Further modelling is performed in order to disentangle the neon seeding effects, which are a direct effect on the turbulence stabilization and an indirect effect on the pedestal parameters. The results suggest that the improved performance with neon is due to a combination of turbulence stabilization and improved pedestal parameters.
The vibration of the double-plated structure containing the inner fluid and elastic connections
Authors: Wen Shitian , Chen Meixia
Published: June 2023

Analytical studies of the vibration characteristics of double-plated structure containing the inner fluid and elastic connections have been performed. An analytical model is first derived to predict the vibration characteristics of the double-plated structure. The transverse displacements of plate and the sound pressure of inner fluid are described by the improved Fourier series. Elastic connections are regarded as springs. In order to simulate arbitrary boundary conditions, the virtual spring technology is applied along each side of the plates. The vibration and sound pressure can be obtained by the Fourier coefficients which calculated by the Rayleigh-Ritz technique. Results from the finite element method (FEM) are well consistent with ones calculated by the analytical method. The effects of parameters on vibration are studied by analytical analyses. It is found that the inner air shows well vibration isolation, while inner water acts as a short circuit in vibration transmission. The stiffness of the elastic connection has significant effects only when the inner fluid is air. When the inner fluid is water, the effect of the spring will be greatly weakened.
Size dependence for mechanical properties of Ti/Cu multilayered nanowire with a semi-coherent interface
Authors: Liu Lanting , Wang Ruifeng , Su Mengjia , An Minrong , Wu Zhibo
Published: June 2023

Metallic multilayered nanowires have a wide application prospect in micro-nano devices because of their superior physical and chemical properties and microstructure designability. Size effects on the tensile behaviors of Ti/Cu multilayered nanowires are investigated by molecular dynamic simulations. Aspect ratios of 1:4, 1:3, 1:2, 1:1, 1:0.75, and 1:0.67 and sectional dimensions of 3, 4, 5, 6, and 7 nm are adopted to construct nanowires with different sizes. Simulation results indicate that the strength of Ti/Cu nanowires decreases with the decrease of aspect ratio in the large aspect ratio range (>1:2) and all simulated sectional dimension ranges, showing a reverse Hall-Petch effect. The Hall-Petch law can only be satisfied in a small aspect ratio range (<1:2). Deformation mechanism transition is found in the critical aspect ratio of 1:2. When the aspect ratio is larger than 1:2, crystalline phases of Ti and Cu layers dominate the plastic deformation of Ti/Cu nanowires. Crystal phases and interface both bear plastic deformation when the aspect ratio is smaller than 1:2. Interface is an important factor in the strength and deformation of Ti/Cu nanowires. The variation of interface fraction and interaction between interface and dislocation motion determine the tendency of strength variation for Ti/Cu nanowires.
A non-Fourier magneto-thermo-viscoelastic problem of a two-dimensional plate
Authors: Li Peng , Zhang Hui
Published: June 2023

Viscoelastic materials is a kind of damping materials which has been wildly applied in vibration control of ocean and civil engineering, and viscoelastic materials mostly work in a complex thermoelectric multi-field coupled environment. In this work, a two-dimensional viscoelastic plate is studied with stain relaxation time and viscoelastic relaxation time. The two-dimensional viscoelastic plate is placed in a magnetic field, and the upper surface is subjected to a thermal shock. The problem is investigated by a modified L-S thermo-viscoelastic model with stain, viscoelastic relaxation time, and magnetic field. Normal mode analysis is used to achieve exact analytical expressions of temperature distribution, displacement component and thermal stresses. Numerical computations are conducted for copper-like material and dimensionless results are illustrated graphically. Based on the results, the influence of magnetic field on the distributions of the nondimensional temperature, displacement and stresses are discussed.
The kinematics and deformation of bubbles when impacting the curved boundary with hydrophilicity and hydrophobicity
Authors: Tang Zijian , Wei Du , Li Guanghua , Du Peng , Hu Haibao , Chen Xiaopeng , Wen Jun , Xie Luo
Published: June 2023

Research on the behavior of bubble collision has always been one of the focuses in the scientific field. This work focuses on the kinematics and deformation of bubbles when impacting the curved boundary with hydrophilicity and hydrophobicity. The impact process of bubbles colliding with the curved wall was recorded by a high-speed camera. The effects of wettability and radius of curvature were analyzed. The results show that when the bubble collides with the hydrophilic curved wall, it will bounce many times until it leaves the wall. Aiming at the phenomenon of liquid film extrusion rupture, a theoretical model is established to deduce the prediction formula of liquid film induction time, which is mainly related to the thickness, the critical rupture thickness, and the compression speed of the liquid film. The prediction error is less than 5.0%.
Appearance of sexaquark in the core of neutron stars as a candidate of dark matter
Authors: Shahrbaf Mahboubeh
Published: June 2023

We study the appearance of sexaquark (uuddss) as a candidate of dark matter in the core of neutron stars while there has been no experimental evidence of this particle in laboratories so far. Regarding the observational constraints of supermassive pulsars as well as gravitational waves, we encounter a sexaquark dilemma for which we introduce a solution by quark deconfinement fulfilling all present constraints from multi-messenger astronomy, i.e., tidal deformability in accordance with GW170817 and maximum mass above the lower limit from PSR J0740+6620.
Can the MDCDW condensate withstand the heat of a cold neutron star?
Authors: Gyory W.
Published: June 2023

The correct description of strongly interacting matter at low temperatures and moderately high densities—in particular the conditions realized inside neutron stars—is still unknown. We review some recent results on the magnetic dual chiral density wave (MDCDW) phase, a candidate phase of quark matter for this region of the QCD phase diagram. We highlight the effects of magnetic fields and temperature on the condensate, which can be explored using a high-order Ginzburg-Landau (GL) expansion. We also explain how the condensate’s nontrivial topology, which arises due to the asymmetry in the lowest Landau level modes, affects its physical properties. Finally, we comment on the possible relevance of these results to neutron star applications. Over a wide range of densities and magnetic field strengths, MDCDW is preferred over the chirally symmetric ground state at temperatures consistent with typical cold neutron stars, and in some cases, even hot ones.
Polymer-mixed Sb2Te3/Te nanocomposites exhibiting p-type to n-type conduction reversal and thermal conductivity reduction
Authors: Meena Dilip Kumar , Bose Rapaka S C , Umarji A M , Babu D Arvindha
Published: June 2023

Sb2Te3-based materials are potential room-temperature thermoelectric materials. In the present work, we choose polycrystalline Sb2Te3/Te nanocomposites and utilize Poly Methyl Methacrylate (PMMA) to reduce the thermal conductivity of Sb2Te3 samples. PMMA and polycrystalline Sb2Te3/Te were well mixed using ball milling. Pellets have been made by the cold press method. Thermoelectric transport properties of Sb2Te3/Te nanocomposites: composition, microstructure, and analysis are found to be influenced by PMMA. With increasing PMMA concentration a p-type to n-type transition has been observed because there are fewer charge carriers or the composites have a higher resistance. It is also observed that the thermal conductivity of Sb2Te3/Te nanocomposites decreases as the PMMA increases. This research paves the way for making the best thermoelectric materials by reducing thermal conductivity through the use of polymers.
The effect of boron oxide on the microstructure and hydration of calcium sulfoaluminate phase
Authors: Ma Qinchuan , Song Fei , Lyu Yinong , Li Geng , Peng Meixun , Zhao Hongwei
Published: June 2023

Boron-rich waste causes numerous environmental problems when discharged directly into the environment. Here, various quantities of boron oxide (B2O3) were added to calcium sulfoaluminate (C4A3$) during the sintering process to demonstrate a potential use of boron-rich waste. The microstructure and hydration performance of C4A3$ with various B2O3contents were investigated with scanning electron microscopy, x-ray diffraction, isothermal conduction calorimetry, thermogravimetric studies and compressive strength tests. B2O3-doped C4A3$ had a larger grain size than the pure phase; and were surrounded by amorphous phases. The presence of B2O3was shown to promote the phase transition process through which C4A3$ changes from the orthorhombic to the cubic structure; and the substitution of Al3+for B3+in AlO4tetrahedra was surveyed by structural refinements. As the B2O3content increased, the induction period of C4A3$ increased while the hydration rate decreased because of the amorphous phases around the C4A3$. However, the hydration degree of doped C4A3$ increased due to the slower reaction rate. Thus, when an appropriate amount of B2O3was added to the C4A3$ during sintering, a significant improvement in the compressive strength of pastes was observed.
Applications and resource reductions in measurement-based variational quantum eigensolvers
Authors: Marqversen Frederik Kofoed , Zinner Nikolaj Thomas
Published: June 2023

We discuss the procedure for obtaining measurement-based implementations of quantum algorithms given by quantum circuit diagrams and how to reduce the required resources needed for a given measurement-based computation. This forms the foundation for quantum computing on photonic systems in the near term. To demonstrate that these ideas are well grounded we present three different problems which are solved by employing a measurement-based implementation of the variational quantum eigensolver algorithm (MBVQE). We show that by utilising native measurement-based gates rather than standard gates, such as the standard controlled not gate (CNOT), measurement-based quantum computations may be obtained that are both shallow and have simple connectivity while simultaneously exhibiting a large expressibility. We conclude that MBVQE has promising prospects for resource states that are not far from what is already available today.
Potential impact of stratospheric aerosol geoengineering on projected temperature and precipitation extremes in South Africa
Authors: Patel Trisha D , Odoulami Romaric C , Pinto Izidine , Egbebiyi Temitope S , Lennard Christopher , Abiodun Babatunde J , New Mark
Published: June 2023

Stratospheric aerosol injection (SAI) is the theoretical deployment of sulphate particles into the stratosphere to reflect incoming solar radiation and trigger a cooling impact at the Earth’s surface. This study assessed the potential impact of SAI geoengineering on temperature and precipitation extremes over South Africa (SAF) and its climatic zones in the future (2075–2095) using simulations from the Stratospheric Aerosol Geoengineering Large Ensemble (GLENS) project. We analyse three different experiments from the GLENS project, each of which simulate stratospheric SO2 injection under the representative concentration pathway 8.5 (RCP8.5) emissions scenario: (i) tropical injection around 22.8–25 km altitude (GLENS), (ii) tropical injection around 1 km above the tropopause (GLENS_low), and (iii) injection near the equator around 20–25 km (GLENS_eq). The study used a set of the Expert Team on Climate Change Detection and Indices describing temperature and rainfall extremes to assess the impact of the three SAI experiments on extreme weather in the future over SAF. The results of this study indicate that, relative to the baseline period (2010–2030), all three SAI experiments are mostly over-effective in offsetting the projected RCP8.5 increase in the frequency of hot (up to −60%) and decrease (up to +10%) in cold temperature extremes over SAF and its climatic zones. These findings suggest that SAI could cause over-cooling in SAF. However, SAI impact on precipitation extremes is less linear and varies across the country’s climatic zones. For example, SAI could reinforce the projected decrease in precipitation extremes across most of SAF, although it could exacerbate heavy precipitation over the KwaZulu-Natal Coast. These findings are consistent across SAI experiments except in magnitude, as GLENS_eq and GLENS_low could cause larger decreases in precipitation extremes than GLENS. These findings imply that SAI could alleviate heat stress on human health, agriculture, and vulnerable communities while simultaneously decreasing infrastructure and crops’ vulnerability to flooding. It is, however, essential to interpret these findings cautiously as they are specific to the SAI experiments and modelling settings considered in the GLENS project.
Sex Differences in Atrial Fibrillation and Associated Complications in Hypertensive Patients with Left Ventricular Hypertrophy: The LIFE Study
Authors: Feinberg Joshua B , Nielsen Emil E , Kjeldsen Sverre E , Devereux Richard B , Gerdts Eva , Wachtell Kristian , Olsen Michael H
Published: June 2023

BACKGROUND

There is no consensus on whether biological differences account for the higher risk of stroke seen in females compared to males with atrial fibrillation (AF).

METHODS

Capitalizing on The Losartan Intervention for Endpoint study, a multicenter randomized clinical trial randomizing 9,193 patients and followed for at least four years, we aimed to identify sex differences in the risk of stroke in the presence of AF in patients with hypertension and left ventricular hypertrophy (LVH).

RESULTS

342 Patients had a history of AF, and 669 developed new-onset AF. History of AF and new-onset AF were more prevalent among males (5.0% vs. 2.9% and 3.0% vs. 0.9%) in patients aged 55–63 years, but the relative difference decreased with age. Females with new-onset AF tended to have a higher risk of stroke than males (HR 1.52 [95% CI 0.95–2.43]). However, females with a history of AF did not have a higher risk than males (HR 0.88 [95% CI 0.5–1.6]). In patients with new-onset AF, the relative higher stroke risk in females increased with age. Among patients with a history of AF, stroke risk was comparable and increased with age in both sexes.

CONCLUSIONS

Among patients with hypertension and LVH, females with new-onset AF had a higher risk of stroke than males, especially in patients above 64 years. However, the risk did not differ between the sexes among patients with a history of AF.
Exposed anthocyanic leaves of Prunus cerasifera are special shade leaves with high resistance to blue light but low resistance to red light against photoinhibition of photosynthesis
Authors: Liu Lu , Fu Zengjuan , Wang Xiangping , Xu Chengyang , Gan Changqing , Fan Dayong , Soon Chow Wah
Published: June 2023

Background and Aims

The photoprotective role of foliar anthocyanins has long been ambiguous: exacerbating, being indifferent to or ameliorating the photoinhibition of photosynthesis. The photoinhibitory light spectrum and failure to separate photo-resistance from repair, as well as the different methods used to quantify the photo-susceptibility of the photosystems, could lead to such a discrepancy.

Methods

We selected two congeneric deciduous shrubs, Prunus cerasifera with anthocyanic leaves and Prunus triloba with green leaves, grown under identical growth conditions in an open field. The photo-susceptibilities of photosystem II (PSII) and photosystem I (PSI) to red light and blue light, in the presence of lincomycin (to block the repair), of exposed leaves were quantified by a non-intrusive P700+ signal from PSI. Leaf absorption, pigments, gas exchange and Chl a fluorescence were also measured.

Key Results

The content of anthocyanins in red leaves (P. cerasifera) was >13 times greater than that in green leaves (P. triloba). With no difference in maximum quantum efficiency of PSII photochemistry (Fv/Fm) and apparent CO2 quantum yield (AQY) in red light, anthocyanic leaves (P. cerasifera) showed some shade-acclimated suites, including lower Chl a/b ratio, lower photosynthesis rate, lower stomatal conductance and lower PSII/PSI ratio (on an arbitrary scale), compared with green leaves (P. triloba). In the absence of repair of PSII, anthocyanic leaves (P. cerasifera) showed a rate coefficient of PSII photoinactivation (ki) that was 1.8 times higher than that of green leaves (P. triloba) under red light, but significantly lower (−18 %) under blue light. PSI of both types of leaves was not photoinactivated under blue or red light.

Conclusions

In the absence of repair, anthocyanic leaves exhibited an exacerbation of PSII photoinactivation under red light and a mitigation under blue light, which can partially reconcile the existing controversy in terms of the photoprotection by anthocyanins. Overall, the results demonstrate that appropriate methodology applied to test the photoprotection hypothesis of anthocyanins is critical.
Shareholder reflective loss: a bogeyman in investment treaty arbitration?
Authors: Ren Raphael
Published: June 2023

Most advanced national legal systems bar shareholders from claiming the diminution in value of their shareholding in a company arising from wrongful acts committed against the company. In contrast, investment arbitral tribunals consistently allow investors to recover such loss because most investment treaties are formulated broadly to protect investments in the form of direct and indirect shareholding. Despite recent calls for reform by governments and inter-governmental organizations, there is nothing inherently wrong with such dissonance. First, the recoverability of ‘shareholder reflective loss’ is doctrinally in sync with the lex specialis characteristics of investment treaty claims. Second, as recently and rightly recognized by the apex courts of the UK and Singapore, the principle of ‘no reflective loss’ is founded upon separation of legal personality rather than prevention of double recovery. In investment treaty arbitration, the latter concern is sufficiently addressed by solutions ranging from jurisdictional barriers (fork-in-the-road and denial of benefits clauses), procedural devices (consolidation and joinder), and substantive defences (res judicata, collateral estoppel, and abuse of process). Hence, the growing fear of shareholder reflective loss undermining the investor–State dispute settlement system is but a bogeyman that States need not be afraid of.
LEGO-CSM: a tool for functional characterization of proteins
Authors: Nguyen Thanh Binh , de Sá Alex G C , Rodrigues Carlos H M , Pires Douglas E V , Ascher David B
Published: June 2023

Motivation

With the development of sequencing techniques, the discovery of new proteins significantly exceeds the human capacity and resources for experimentally characterizing protein functions. Localization, EC numbers, and GO terms with the structure-based Cutoff Scanning Matrix (LEGO-CSM) is a comprehensive web-based resource that fills this gap by leveraging the well-established and robust graph-based signatures to supervised learning models using both protein sequence and structure information to accurately model protein function in terms of Subcellular Localization, Enzyme Commission (EC) numbers, and Gene Ontology (GO) terms.

Results

We show our models perform as well as or better than alternative approaches, achieving area under the receiver operating characteristic curve of up to 0.93 for subcellular localization, up to 0.93 for EC, and up to 0.81 for GO terms on independent blind tests.

Availability and implementation

LEGO-CSM’s web server is freely available at https://biosig.lab.uq.edu.au/lego_csm. In addition, all datasets used to train and test LEGO-CSM’s models can be downloaded at https://biosig.lab.uq.edu.au/lego_csm/data.
Robust joint clustering of multi-omics single-cell data via multi-modal high-order neighborhood Laplacian matrix optimization
Authors: Jiang Hao , Zhan Senwen , Ching Wai-Ki , Chen Luonan
Published: June 2023

Motivation

Simultaneous profiling of multi-omics single-cell data represents exciting technological advancements for understanding cellular states and heterogeneity. Cellular indexing of transcriptomes and epitopes by sequencing allowed for parallel quantification of cell-surface protein expression and transcriptome profiling in the same cells; methylome and transcriptome sequencing from single cells allows for analysis of transcriptomic and epigenomic profiling in the same individual cells. However, effective integration method for mining the heterogeneity of cells over the noisy, sparse, and complex multi-modal data is in growing need.

Results

In this article, we propose a multi-modal high-order neighborhood Laplacian matrix optimization framework for integrating the multi-omics single-cell data: scHoML. Hierarchical clustering method was presented for analyzing the optimal embedding representation and identifying cell clusters in a robust manner. This novel method by integrating high-order and multi-modal Laplacian matrices would robustly represent the complex data structures and allow for systematic analysis at the multi-omics single-cell level, thus promoting further biological discoveries.

Availability and implementation

Matlab code is available at https://github.com/jianghruc/scHoML.
Information-incorporated sparse convex clustering for disease subtyping
Authors: Zhang Xiaoyu , Liu Ching-Ti
Published: June 2023

Motivation

Heterogeneity in human diseases presents clinical challenges in accurate disease characterization and treatment. Recently available high throughput multi-omics data may offer a great opportunity to explore the underlying mechanisms of diseases and improve disease heterogeneity assessment throughout the treatment course. In addition, increasingly accumulated data from existing literature may be informative about disease subtyping. However, the existing clustering procedures, such as Sparse Convex Clustering (SCC), cannot directly utilize the prior information even though SCC produces stable clusters.

Results

We develop a clustering procedure, information-incorporated Sparse Convex Clustering, to respond to the need for disease subtyping in precision medicine. Utilizing the text mining approach, the proposed method leverages the existing information from previously published studies through a group lasso penalty to improve disease subtyping and biomarker identification. The proposed method allows taking heterogeneous information, such as multi-omics data. We conduct simulation studies under several scenarios with various accuracy of the prior information to evaluate the performance of our method. The proposed method outperforms other clustering methods, such as SCC, K-means, Sparse K-means, iCluster+, and Bayesian Consensus Clustering. In addition, the proposed method generates more accurate disease subtypes and identifies important biomarkers for future studies in real data analysis of breast and lung cancer-related omics data. In conclusion, we present an information-incorporated clustering procedure that allows coherent pattern discovery and feature selection.

Availability and implementation

The code is available upon request.
Cytomolecular characterization of early and late condensing chromosome regions in some Annonaceae species
Authors: Santos Amanda , Nascimento Thiago , ﻿Felix Leonardo P , Guerra Marcelo
Published: June 2023

The condensation patterns (CPs) of prophase chromosomes represent poorly explored and little understood karyotype features. Three distinct chromosome domains are observed in conventionally stained prophases of most angiosperms with small chromosomes: heterochromatin and early condensing euchromatin (ECEu), which are observed as early condensing regions (ECRs), and late condensing euchromatin or late condensing regions (LCRs). All three prophase domains have been often reported in the Annonaceae species. To gain a better understanding of these regions, we investigated the CPs, heterochromatic bands, and rDNA sites in seven Annona species with 2n = 14, 28, and 54 and Xylopiafrutescens with 2n = 16. Besides, histone H4K5 acetylation, telomeric sites, and DNA methylation were analysed in some of these species. LCRs corresponded to a small hyperacetylated, and hypomethylated fraction of the metaphase chromosomes. During interphase, the chromocentres displayed variable proportions of heterochromatin and ECEu. The LCRs and ECRs were conserved even between disploid and polyploid species, whereas rDNA sites and heterochromatic bands varied in number and location. Our data suggest that chromatin compartmentalization in ECR and LCR regions may represent the simplest functional organization of the small chromosomes of Annonaceae, while the remaining characters are less relevant.
Notch4 participates in mesenchymal stem cell-induced differentiation in 3D-printed matrix and is implicated in eccrine sweat gland morphogenesis
Authors: Wang Yuzhen , Zhang Fanliang , Yao Bin , Hou Linhao , Li Zhao , Song Wei , Kong Yi , Tan Yaxin , Fu Xiaobing , Huang Sha
Published: June 2023

Background

Eccrine sweat gland (SG) plays a crucial role in thermoregulation but exhibits very limited regenerative potential. Although SG lineage-restricted niches dominate SG morphogenesis and benefit SG regeneration, rebuilding niches in vivo is challenging for stem cell therapeutic applications. Hence, we attempted to screen and tune the critical niche-responding genes that dually respond to both biochemical and structural cues, which might be a promising strategy for SG regeneration.

Methods

An artificial SG lineage-restricted niche consisting of mouse plantar dermis homogenates (i.e. biochemical cues) and 3D architecture (i.e. structural cues) was built in vitro by using an extrusion-based 3D bioprinting approach. Mouse bone marrow-derived mesenchymal stem cells (MSCs) were then differentiated into the induced SG cells in the artificial SG lineage-restricted niche. To decouple biochemical cues from structural cues, the transcriptional changes aroused by pure biochemical cues, pure structural cues and synergistic effects of both cues were analyzed pairwise, respectively. Notably, only niche-dual-responding genes that are differentially expressed in response to both biochemical and structural cues and participate in switching MSC fates towards SG lineage were screened out. Validations in vitro and in vivo were respectively conducted by inhibiting or activating the candidate niche-dual-responding gene(s) to explore the consequent effects on SG differentiation.

Results

Notch4 is one of the niche-dual-responding genes that enhanced MSC stemness and promoted SG differentiation in 3D-printed matrix in vitro. Furthermore, inhibiting Notch4 specifically reduced keratin 19-positive epidermal stem cells and keratin 14-positive SG progenitor cells, thus further delaying embryonic SG morphogenesis in vivo.

Conclusions

Notch4 not only participates in mouse MSC-induced SG differentiation in vitro but is also implicated in mouse eccrine SG morphogenesis in vivo.
A Multicenter Retrospective Cohort Study to Characterize Patients Hospitalized With Multisystem Inflammatory Syndrome in Adults and Coronavirus Disease 2019 in the United States, 2020–2021
Authors: Melgar Michael , Abrams Joseph Y , Godfred-Cato Shana , Shah Ami B , Garg Amit , Strunk Andrew , Narasimhan Mangala , Koptyev Jonathan , Norden Alexandra , Musheyev David , Rashid Fahmida , Tannenbaum Rachel , Estrada-Y-Martin Rosa M , Patel Bela , Karanth Siddharth , Achenbach Chad J , Hall Gavin T , Hockney Sara M , Caputo Matthew , Abbo Lilian M , Beauchamps Laura , Morris Stephen , Cifuentes Renzo O , de St Maurice Annabelle , Bell Douglas S , Prabaker Kavitha K , Sanz Vidorreta Fernando J , Bryant Evan , Cohen David K , Mohan Rohith , Libby Christopher P , SooHoo Spencer , Domingo Tristel J , Campbell Angela P , Belay Ermias D
Published: June 2023

Background

The diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)–associated multisystem inflammatory syndrome in adults (MIS-A) requires distinguishing it from acute coronavirus disease 2019 (COVID-19) and may affect clinical management.

Methods

In this retrospective cohort study, we applied the US Centers for Disease Control and Prevention case definition to identify adults hospitalized with MIS-A at 6 academic medical centers from 1 March 2020 to 31 December 2021. Patients MIS-A were matched by age group, sex, site, and admission date at a 1:2 ratio to patients hospitalized with acute symptomatic COVID-19. Conditional logistic regression was used to compare demographic characteristics, presenting symptoms, laboratory and imaging results, treatments administered, and outcomes between cohorts.

Results

Through medical record review of 10 223 patients hospitalized with SARS-CoV-2–associated illness, we identified 53 MIS-A cases. Compared with 106 matched patients with COVID-19, those with MIS-A were more likely to be non-Hispanic black and less likely to be non-Hispanic white. They more likely had laboratory-confirmed COVID-19 ≥14 days before hospitalization, more likely had positive in-hospital SARS-CoV-2 serologic testing, and more often presented with gastrointestinal symptoms and chest pain. They were less likely to have underlying medical conditions and to present with cough and dyspnea. On admission, patients with MIS-A had higher neutrophil-to-lymphocyte ratio and higher levels of C-reactive protein, ferritin, procalcitonin, and D-dimer than patients with COVID-19. They also had longer hospitalization and more likely required intensive care admission, invasive mechanical ventilation, and vasopressors. The mortality rate was 6% in both cohorts.

Conclusions

Compared with patients with acute symptomatic COVID-19, adults with MIS-A more often manifest certain symptoms and laboratory findings early during hospitalization. These features may facilitate diagnosis and management.