bluuebunny/crossref_metadata_2025 huggingface dataset:
Mobility and phone call behavior explain patterns in poverty at high-resolution across multiple settings
Authors: Steele Jessica E. , Pezzulo Carla , Albert Maximilian , Brooks Christopher J. , zu Erbach-Schoenberg Elisabeth , O’Connor Siobhán B. , Sundsøy Pål R. , Engø-Monsen Kenth , Nilsen Kristine , Graupe Bonita , Nyachhyon Rajesh Lal , Silpakar Pradeep , Tatem Andrew J.
Published: November 2021

Call detail records (CDRs) from mobile phone metadata are a promising data source for mapping poverty indicators in low- and middle-income countries. These data provide information on social networks, call behavior, and mobility patterns in a population, which are correlated with measures of socioeconomic status. CDRs are passively collected and provide information with high spatial and temporal resolution. Identifying features from these data that are generalizable and able to predict poverty and wealth beyond a single context could promote broader usage of mobile data, contribute to a reduction in the cost of socioeconomic data collection and processing, as well as complement existing census and survey-based methods of poverty estimation with improved temporal resolution. This is especially important within the context of the sustainable development goals (SDGs), where poverty and related health indicators are to be reduced significantly across subnational geographies by 2030. Here we utilize measures of cell phone user behavior derived from three CDR datasets within a Bayesian modeling framework to map poverty and wealth patterns across Namibia, Nepal, and Bangladesh. We demonstrate five metrics of user mobility and call behavior that are able to explain between 50% and 65% of the variance in socioeconomic status nationally for these three countries. These key metrics prove useful in very different contexts and can be readily provided as part of an existing CDR platform or software package. This paper provides a key contribution in this regard by identifying such metrics relevant to estimating poverty. We highlight the inclusion of ancillary data and local context as an important factor in understanding model outputs when targeting poverty alleviation strategies.
Scientific Value Relativism
Authors: Ruiz-Gallardón Isabel
Published: November 2021

Relativism stresses that value judgements are statements about meaning and not about facts, about “ought” and not about “is”. Professor Arnold Brecht explained and substantiated the existence of a link between “is” and “ought”, which does not have a logical character, but does indeed have a “factual” one; a link that, being so evident and intersubjectively transmissible, makes doctrine based on logical separation less important. Suffice it to observe this factual link in a sufficient number of individual cases to arrive inductively at the conclusion of its universal presence with the same certainty or uncertainty as any other inductive conclusion. This paper studies the considerations made by Brecht in the first half of the twentieth century on universal elements that do not derive from arbitrary decisions on justice, but can stem from the necessary feelings inherent to human beings. Confirming this is within the bounds of scientific research. And if these elements are considered as a whole and combined with the two methods proposed by the relativists—clarifying the meaning of the proposed interpretations and analysing their implications—the demonstrable elements obtained are of considerable worth.
Line-solitons of a two-component KP hierarchy
Authors: Hu Changgen , Li Chuanzhong
Published: November 2021

In this paper, we mainly study the line-solitons’ solutions of a two-component coupled Kadomtsev–Petviashvili hierarchy on Grassmannian $Gr (N, M)$ and also represent the interaction between two layers of fluids. Its solutions are given by $u (x, y, t)$ and $\hat {u} (x, y, t)$ if we focus on the first three variables. Such solutions $u$ and $\hat {u}$ are defined by a point of the totally non-negative Grassmannian $Gr (N, M)$. In addition, we also describe the interaction law between $u$ and $\hat {u}$ by studying the relationship between $u$, $\hat {u}$ and the coefficient $\epsilon$.
A full relativistic model of electron cyclotron current drive efficiency in tokamak plasmas
Authors: Hu Y. M. , Hu Y. J. , Chen J. L. , Huang Y. H. , Tao J. , Ma L. H. , Wang L. Q.
Published: November 2021

A fully relativistic model of electron cyclotron current drive (ECCD) efficiency based on the adjoint function techniques is considered. Numerical calculations of the current drive efficiency in a tokamak by using the variational approach are performed. A fully relativistic extension of the variational principle with the modified test function for the Spitzer function with momentum conservation in the electron–electron collision is described in general tokamak geometry. The model developed has generalized that of Marushchenko et al., which is extended for arbitrary temperatures and covers exactly the asymptotic for u≫1 when Zeff≫1, and is suited to ray-tracing and beam-tracing calculations. As a demonstration, the new model is applied in one of widely used ray-tracing codes, TORAY-GA, and yields distinct improvement on the fidelity for the calculation of ECCD in the hybrid operating scenario for the China fusion engineering test reactor.
Massively parallel linear-scaling Hartree–Fock exchange and hybrid exchange–correlation functionals with plane wave basis set accuracy
Authors: Dziedzic Jacek , Womack James C. , Ali Rozh , Skylaris Chris-Kriton
Published: November 2021

We extend our linear-scaling approach for the calculation of Hartree–Fock exchange energy using localized in situ optimized orbitals [Dziedzic et al., J. Chem. Phys. 139, 214103 (2013)] to leverage massive parallelism. Our approach has been implemented in the onetep (Order-N Electronic Total Energy Package) density functional theory framework, which employs a basis of non-orthogonal generalized Wannier functions (NGWFs) to achieve linear scaling with system size while retaining controllable near-complete-basis-set accuracy. For the calculation of Hartree–Fock exchange, we use a resolution-of-identity approach, where an auxiliary basis set of truncated spherical waves is used to fit products of NGWFs. The fact that the electrostatic potential of spherical waves (SWs) is known analytically, combined with the use of a distance-based cutoff for exchange interactions, leads to a calculation cost that scales linearly with the system size. Our new implementation, which we describe in detail, combines distributed memory parallelism (using the message passing interface) with shared memory parallelism (OpenMP threads) to efficiently utilize numbers of central processing unit cores comparable to, or exceeding, the number of atoms in the system. We show how the use of multiple time-memory trade-offs substantially increases performance, enabling our approach to achieve superlinear strong parallel scaling in many cases and excellent, although sublinear, parallel scaling otherwise. We demonstrate that in scenarios with low available memory, which preclude or limit the use of time-memory trade-offs, the performance degradation of our algorithm is graceful. We show that, crucially, linear scaling with system size is maintained in all cases. We demonstrate the practicability of our approach by performing a set of fully converged production calculations with a hybrid functional on large imogolite nanotubes up to over 1400 atoms. We finish with a brief study of how the employed approximations (exchange cutoff and the quality of the SW basis) affect the calculation walltime and the accuracy of the obtained results.
Bifurcations of clusters and collective oscillations in networks of bistable units
Authors: Salman Munir , Bick Christian , Krischer Katharina
Published: November 2021

We investigate dynamics and bifurcations in a mathematical model that captures electrochemical experiments on arrays of microelectrodes. In isolation, each individual microelectrode is described by a one-dimensional unit with a bistable current-potential response. When an array of such electrodes is coupled by controlling the total electric current, the common electric potential of all electrodes oscillates in some interval of the current. These coupling-induced collective oscillations of bistable one-dimensional units are captured by the model. Moreover, any equilibrium is contained in a cluster subspace, where the electrodes take at most three distinct states. We systematically analyze the dynamics and bifurcations of the model equations: We consider the dynamics on cluster subspaces of successively increasing dimension and analyze the bifurcations occurring therein. Most importantly, the system exhibits an equivariant transcritical bifurcation of limit cycles. From this bifurcation, several limit cycles branch, one of which is stable for arbitrarily many bistable units.
The influence of the Nb:Ta ratio on the microstructural evolution in refractory metal superalloy systems
Authors: Whitfield T. E. , Wise G. J. , Stone H. J. , Jones N. G.
Published: November 2021

Refractory metal superalloys have the potential to facilitate a significant increase in gas turbine operating temperatures that would enhance efficiency and reduce emissions. However, fulfilling this potential requires a much more detailed understanding of the underlying metallurgy and how it is influenced by alloying additions. Here, the influence of systematically varying the Nb:Ta ratio in a series of Ti–Zr–Nb–Ta alloys has been studied and compared to thermodynamic predictions. The experimental results show that higher Nb:Ta ratios suppress phase separation but lower the inter-phase misfit. As such, optimizing these alloys for specific applications will require careful balancing of these effects.
omg blueprint for trapped ion quantum computing with metastable states
Authors: Allcock D. T. C. , Campbell W. C. , Chiaverini J. , Chuang I. L. , Hudson E. R. , Moore I. D. , Ransford A. , Roman C. , Sage J. M. , Wineland D. J.
Published: November 2021

Quantum computers, much like their classical counterparts, will likely benefit from flexible qubit encodings that can be matched to different tasks. For trapped ion quantum processors, a common way to access multiple encodings is to use multiple, co-trapped atomic species. Here, we outline an alternative approach that allows flexible encoding capabilities in single-species systems through the use of long-lived metastable states as an effective, programmable second species. We describe the set of additional trapped ion primitives needed to enable this protocol and show that they are compatible with large-scale systems that are already in operation.
Monopoles in a zonal flow with constant shear on a quasi-geostrophic f-plane: Effects of Galilean non-invariance
Authors: Reznik Gregory , Kravtsov Sergey
Published: November 2021

Building on the work of Kravtsov and Reznik [J. Fluid Mech. 909, A23 (2021); hereafter KR21], we studied the interactions of a localized monopole with a rectilinear, constant-shear flow in a 1½-layer, f-plane, quasi-geostrophic model. The non-invariance of this model with respect to Galilean transformations plays a crucial role in the dynamics of such interactions. Of particular importance here are two configurations in which the center of the vortex is located on the line of zero zonal current and remains motionless in the background of a nonstationary flow field generated via interactions of the vortex with the zonal flow. In configuration I (II), the vortex is prograde (retrograde), that is, its vorticity is of the same (opposite) sign with the vorticity of the background flow. Configuration I is stable, whereas configuration II eventually breaks down: a retrograde vortex drifts off of the zero-current line, rapidly accelerates and radiates intense Rossby waves, which results in a gradual weakening of the vortex. Naturally, the same scenario plays out if a retrograde vortex is initially off of the zero-current line. On the other hand, a prograde vortex initially located at some distance from the zero-current line drifts toward this line, albeit at a rate that decreases with time, so the solution always tends to configuration I. Therefore, the line of zero zonal current “attracts” prograde vortices and “repels” retrograde vortices. The present numerical experiments with singular vortices, using the scheme developed in KR21, confirm the above scenarios and clarify their dynamics.
Highly efficient spin-current generation from Pt/Ru multilayers
Authors: Bai Qiaoning , Zhai Yongbo , Yun Jijun , Zhang Jianrong , Chang Meixia , Zuo Yalu , Xi Li
Published: November 2021

Increasing spin Hall angle of heavy metals has attracted considerable attention due to their potential applications in spintronic technology. Here, we demonstrate that the spin Hall angle could be enhanced dramatically in the Ta/[Pt/Ru]n/Pt/Co/Ta multilayers. The spin Hall angle reaches a maximum value of 0.28 when n = 5 from the loop-shift method with a relative low resistivity of approximately 48 μΩ cm. Meanwhile a minimum critical switching current density approximately 3.2 × 106 A/cm2 under an in-plane bias magnetic field around 5% of the perpendicular anisotropy field was obtained for the sample with n = 5 in current-induced magnetization switching experiment. We find that the extrinsic spin Hall mechanism changes from the spin skew scattering when n < 2 to spin side-jump mechanism when n > 2. This work provides an effective way in increasing spin Hall angle for low-power consumption spintronics devices.
Terahertz pulse-induced Néel vector switching in α-Fe2O3/Pt heterostructures
Authors: Huang Lin , Zhou Yongjian , Qiu Hongsong , Guo Tingwen , Pan Feng , Jin Biaobing , Song Cheng
Published: November 2021

The increasing interest in antiferromagnetic electronics is driven by the vision of the operation in the terahertz regime and ultrahigh density memories. The use of a terahertz wave to scale up the writing speed to terahertz has been reported in the antiferromagnetic single layer CuMnAs with sublattice symmetry broken. Here, a reversible and reproducible switching in antiferromagnetic insulators α-Fe2O3 is achieved in α-Fe2O3/Pt heterostructures by a terahertz wave pulse, and the switching capability is consistent with the current pulse-induced switching counterpart. The temperature variation during the terahertz pulse is simulated by finite element simulation analysis, for extreme (∼1.5 ps) short terahertz pulses, the thermal effect can be negligible and the mechanism responsible for the terahertz pulse-induced antiferromagnetic switching points to the dampinglike spin–orbit torque. Our finding paves the way for the antiferromagnet/heavy metal bilayers for ultrahigh density memories and high-frequency devices up to terahertz operation.
Mitigation of breathing oscillations and focusing of the plume in a segmented electrode wall-less Hall thruster
Authors: Simmonds J. , Raitses Y.
Published: November 2021

In the absence of the channel walls bounding the plasma, a wall-less Hall thruster is a promising configuration with a potentially longer lifetime and easier scalability than conventional Hall thrusters. Because the ion acceleration takes place in the fringing magnetic field with a strong axial component, the operation of a typical wall-less thruster is characterized by a large beam divergence of the plasma flow, which reduces the thrust. In this work, the addition of a biased segmented electrode to the wall-less thruster is shown to significantly narrow the plasma plume and suppress large amplitude breathing oscillations of the discharge current commonly associated with ionization instability. Both effects result in improvements to the thruster performance. Physical mechanisms responsible for these effects are unclear, but they are apparently associated with the reduction of the electron cross field transport to the anode and a transition in the breathing mode frequency.
Rayleigh–Bénard convection in non-Newtonian fluids: Experimental and theoretical investigations
Authors: Bouteraa Mondher , Varé Thomas , Nouar Chérif , Becker Simon , Ouhajjou Jamal
Published: November 2021

We present an experimental and theoretical study of Rayleigh–Bénard convection in shear-thinning fluids with temperature-dependent properties. Experiments were performed using a cylindrical cell with a radius R̂=60  mm and height adjustable at d̂=15 and 20  mm giving a radius-to-height ratio L = 4 and 3, respectively. The fluids used are glycerol (Newtonian fluid) and aqueous xanthan gum solutions (shear-thinning fluids) at 1000 and 1200 ppm. Convection patterns are visualized by the shadowgraph method. In the theoretical part of this study, the weakly nonlinear analysis performed by Varé et al. [J. Fluid Mech. 905, A33 (2020)] is extended to take into account the variation of the thermal expansion coefficient with temperature. For the xanthan gum solutions used, the temperature dependence of the fluid parameters is sufficiently strong to obtain hexagonal cells at the onset of convection. It has been observed that their size decreases with the increase in the temperature difference across the fluid layer above the critical value. This result provides an experimental support to our theoretical study where it is shown that for hexagons, the band of stable wavenumbers is bent toward higher wavenumbers. For the glycerol, Newtonian fluid with a large Prandtl number, a slight increase in the wavelength of rolls is observed in agreement with the literature.
Generalized Kohn–Sham equations with accurate total energy and single-particle eigenvalue spectrum
Authors: Pitts Thomas C. , Lathiotakis Nektarios N. , Gidopoulos Nikitas
Published: November 2021

We propose a new generalized Kohn–Sham or constrained hybrid method, where the exchange potential is the (equally weighted) average of the nonlocal Fock–exchange term and the self-interaction-corrected exchange potential, as obtained from our constrained minimization method of semi-local approximations. The new method gives an accurate single-particle eigenvalue spectrum with an average deviation between (the negative of) the valence orbital eigenvalues and the experimental ionization potentials of about 0.5 eV, while the deviation of core orbitals is within 2 eV. The improvement in the eigenvalue spectrum is achieved with a minimal increase in the total energy.
Chemical bonding theories as guides for self-interaction corrected solutions: Multiple local minima and symmetry breaking
Authors: Trepte Kai , Schwalbe Sebastian , Liebing Simon , Schulze Wanja T. , Kortus Jens , Myneni Hemanadhan , Ivanov Aleksei V. , Lehtola Susi
Published: November 2021

Fermi–Löwdin orbitals (FLOs) are a special set of localized orbitals, which have become commonly used in combination with the Perdew–Zunger self-interaction correction (SIC) in the FLO-SIC method. The FLOs are obtained for a set of occupied orbitals by specifying a classical position for each electron. These positions are known as Fermi-orbital descriptors (FODs), and they have a clear relation to chemical bonding. In this study, we show how FLOs and FODs can be used to initialize, interpret, and justify SIC solutions in a common chemical picture, both within FLO-SIC and in traditional variational SIC, and to locate distinct local minima in either of these approaches. We demonstrate that FLOs based on Lewis theory lead to symmetry breaking for benzene—the electron density is found to break symmetry already at the symmetric molecular structure—while ones from Linnett’s double-quartet theory reproduce symmetric electron densities and molecular geometries. Introducing a benchmark set of 16 planar cyclic molecules, we show that using Lewis theory as the starting point can lead to artifactual dipole moments of up to 1 D, while Linnett SIC dipole moments are in better agreement with experimental values. We suggest using the dipole moment as a diagnostic of symmetry breaking in SIC and monitoring it in all SIC calculations. We show that Linnett structures can often be seen as superpositions of Lewis structures and propose Linnett structures as a simple way to describe aromatic systems in SIC with reduced symmetry breaking. The role of hovering FODs is also briefly discussed.
Interconversion-controlled liquid–liquid phase separation in a molecular chiral model
Authors: Uralcan Betul , Longo Thomas J. , Anisimov Mikhail A. , Stillinger Frank H. , Debenedetti Pablo G.
Published: November 2021

Liquid–liquid phase separation of fluids exhibiting interconversion between alternative states has been proposed as an underlying mechanism for fluid polyamorphism and may be of relevance to the protein function and intracellular organization. However, molecular-level insight into the interplay between competing forces that can drive or restrict phase separation in interconverting fluids remains elusive. Here, we utilize an off-lattice model of enantiomers with tunable chiral interconversion and interaction properties to elucidate the physics underlying the stabilization and tunability of phase separation in fluids with interconverting states. We show that introducing an imbalance in the intermolecular forces between two enantiomers results in nonequilibrium, arrested phase separation into microdomains. We also find that in the equilibrium case, when all interaction forces are conservative, the growth of the phase domain is restricted only by the system size. In this case, we observe phase amplification, in which one of the two alternative phases grows at the expense of the other. These findings provide novel insights on how the interplay between dynamics and thermodynamics defines the equilibrium and steady-state morphologies of phase transitions in fluids with interconverting molecular or supramolecular states.
Three-dimensional spatial-temporal evolution and dynamics of the tip leakage vortex in an oil–gas multiphase pump
Authors: Shu Zekui , Shi Guangtai , Tao Sijia , Tang Wanqi , Li Changxu
Published: November 2021

To explore the spatial-temporal evolution and dynamics of the tip leakage vortex (TLV) in an oil–gas multiphase pump, the TLV was captured accurately and vortex structures were analyzed in detail under different operating conditions. Results revealed that the TLV structures included the leading edge vortex, tip separation vortex, primary tip leakage vortex (PTLV), secondary tip leakage vortex (STLV), and trailing edge vortex. In one impeller rotation period, the three-dimensional spatial-temporal evolution of the TLV could be divided into three stages: splitting, shrinking, and merging. In this process, the spatial-temporal evolution of the PTLV and STLV was closely correlated. In addition, the relative vorticity transport equation was used to analyze the TLV near the tip clearance region of the impeller. Results showed that the relative vortex stretching item (RVS), Coriolis force (CORF), and viscous diffusion (VISD) jointly controlled the spatial-temporal evolution of the TLV and were the dynamic sources of variation in the vorticity and trajectory of the TLV. In particular, the gas phase changed the distributions of the RVS, CORF, and VISD on the intensity isosurface of the TLV and had a significant effect on the spatial-temporal evolution of the TLV.
Evaluation of an online toolkit for carers of people with a life-limiting illness at the end-of-life: health professionals’ perspectives
Authors: Parker D. , Hudson P. , Tieman J. , Thomas K. , Saward D. , Ivynian S.
Published: November 2021

Carers of people with a life-limiting illness report unmet information, practical, and emotional support needs, and are often unaware of services available to help improve preparedness, wellbeing, and reduce strain. CarerHelp is the first e-health toolkit that focuses on the information and support needs of carers of people with a life-limiting illness at the end-of-life, using a pathway approach. This study investigated the usefulness of CarerHelp, from the perspective of health professionals who care for these people. Through a 10-min online survey, health professionals provided feedback about their user experience and perceived usefulness of the website. Their expert opinion was sought to ascertain whether CarerHelp could increase carers’ preparedness and confidence to support the person for whom they are caring and thereby improve carers’ own psychological wellbeing. Health professionals also evaluated whether CarerHelp adequately raised awareness of support services available. CarerHelp was perceived as a useful resource for increasing preparedness for the caring role, including physical tasks and emotional support. Health professionals reported that CarerHelp would increase carers’ knowledge of services, confidence to care and ability for self-care. Health professionals endorsed CarerHelp as a useful information source, guide for support, and would promote CarerHelp to clients and their families.
Choice of monitoring method can influence estimates of usage of artificial hollows by vertebrate fauna
Authors: Honey Reannan , McLean Christopher M. , Murray Brad R. , Callan Michael N. , Webb Jonathan K.
Published: November 2021

The loss of hollow-bearing trees is a key threat for many hollow-dependent taxa. Nesting boxes have been widely used to offset tree hollow loss, but they have high rates of attrition, and, often, low rates of usage by target species. To counter these problems, chainsaw carved hollows (artificial cavities cut into trees) have become a popular alternative, yet little research has been published on their effectiveness. We examined the usage of 150 chainsaw carved hollows by cavity-dependent fauna in the central west of New South Wales using observations from traditional inspection methods and remote cameras. Between October 2017 and April 2019, we detected 21 species of vertebrates (two reptile, one amphibian, 10 bird, and eight mammal species) inside chainsaw carved hollows, but the number of species detected was dependent on the chosen monitoring method. We detected six species inside hollows during physical inspections, whereas remote cameras detected 21 species entering hollows. Cameras detected eight species using hollows as breeding sites, whereas physical inspections detected just four species. Cameras detected two threatened mammals (squirrel glider (Petaurus norfolcensis) and greater glider (Petauroides volans)) raising young inside hollows, yet we failed to detect these species during physical inspections. For birds, the two methods yielded equivalent results for detection of breeding events. Overall, our study showed that few cavity-dependent species used chainsaw carved hollows as breeding sites. This highlights how artificial hollows are not a substitute for retaining naturally occurring hollows in large trees and revegetation programs.
Click chemistry–enabled CRISPR screening reveals GSK3 as a regulator of PLD signaling
Authors: Bumpus Timothy W. , Huang Shiying , Tei Reika , Baskin Jeremy M.
Published: November 2021

Significance

The application of CRISPR-Cas9 to genome-wide screening has revolutionized our ability to discover new functions for genes and regulators of physiological processes. However, a major constraint placed on such screens is the choice of phenotypic selection step, typically limited to live/dead or conventional fluorescent reporter/labeling. Here, we develop a CRISPR interference–based screening platform harnessing click chemistry tagging to reveal regulators of a specific signaling pathway. Using this tool, we discovered a regulatory circuit involving glycogen synthase kinase 3 and protein kinase C in the control of phospholipase D signaling. More broadly, this work illustrates how emergent chemical biology approaches can expand the power of genome-wide CRISPR screening to elucidate mechanisms regulating specific enzyme-driven signaling pathways.
Lymph node formation and B cell homeostasis require IKK-α in distinct endothelial cell–derived compartments
Authors: McCorkell Kelly A. , Jayachandran Nipun , Cully Michelle D. , Freund-Brown Jacquelyn , Weinkopff Tiffany , Monslow James , Hu Yinling , Puré Ellen , Freedman Bruce D. , Alvarez Jorge I. , Cancro Michael P. , May Michael J.
Published: November 2021

Significance

Noncanonical NF-κB controls lymph node (LN) formation and B cell homeostasis. We previously demonstrated that IKK-α–dependent noncanonical NF-κB signaling is activated in vascular endothelial cells (ECs). Here, we find that ablation of IKK-α in ECs leads to complete loss of LNs and markedly reduced B cell numbers, recapitulating the phenotype of global IKK-α inactivation. Using cell type–specific conditional knockout models, we find that loss of IKK-α in hematopoietic cells underlies the B cell defect, whereas deletion in lymphatic ECs (LECs) results in the absence of LNs. Thus, our findings reveal that IKK-α in distinct EC-derived compartments is uniquely required to promote B cell homeostasis and LN development and demonstrate that LEC-intrinsic IKK-α is essential for LN formation.
The physical basis of mollusk shell chiral coiling
Authors: Chirat Régis , Goriely Alain , Moulton Derek E.
Published: November 2021

Significance

A theoretical model suggests that a mechanically induced twist of the soft body underlies the formation of helicospiral shells in snails and ammonites and also accounts for the startling and unique meandering shells observed in certain species. This theory addresses fundamental developmental issues of chirality and symmetry breaking: in the case of ammonites, how a bilaterally symmetric body can sometimes secrete a nonsymmetric shell; for gastropods, how an intrinsic twist possibly due to the asymmetric development of musculature can provide a mechanical motor for generating a chiral shell. Our model highlights the importance of physical forces in biological development and sheds light on shell coiling in snails, which have been used for a century as model organisms in genetic research.
Claudin-2 and claudin-12 form independent, complementary pores required to maintain calcium homeostasis
Authors: Beggs Megan R. , Young Kennedi , Pan Wanling , O’Neill Debbie D. , Saurette Matthew , Plain Allein , Rievaj Juraj , Doschak Michael R. , Cordat Emmanuelle , Dimke Henrik , Alexander R. Todd
Published: November 2021

Significance

Significant calcium absorption across renal and intestinal epithelia occurs via the paracellular pathway. However, the identity of the paracellular pore involved is unknown. Claudin-2 and claudin-12 contribute paracellular calcium permeability in cell models, but single knockout animals don’t have altered serum calcium or bone mineralization. To investigate this,
Cldn2/12
double knockout mice were generated. They display decreased intestinal calcium absorption and renal calcium wasting, resulting in hypocalcemia and markedly reduced bone mineralization. Claudin-2 and claudin-12 don’t physically interact in vitro, and coexpression has an additive effect on calcium permeability. Our work identifies claudin-2 and claudin-12 as important constituents of the paracellular Ca
2+
pathway in intestine and kidney enabling calcium transport and highlights their important complementary roles in maintaining calcium homeostasis.
Scaling concepts in ‘omics: Nuclear lamin-B scales with tumor growth and often predicts poor prognosis, unlike fibrosis
Authors: Vashisth Manasvita , Cho Sangkyun , Irianto Jerome , Xia Yuntao , Wang Mai , Hayes Brandon , Wieland Daniel , Wells Rebecca , Jafarpour Farshid , Liu Andrea , Discher Dennis E.
Published: November 2021

Significance

Nonlinear scaling analyses pervade polymer physics and chemistry, yielding characteristic exponents that conceivably apply to expressed genes and their assemblies. Stoichiometric scaling and fractal scaling indeed emerge as gene-gene power laws in human cancer data for key structural polymers in nuclei or extracellular matrix. Only one nuclear envelope factor, lamin-B1, scales with tumor proliferation genes, predicting poor survival for multiple cancers, including liver cancer. These genes include one transcription factor that directly regulates lamin-B1 and broadly categorizes prognosis. In contrast, collagen-1 scales with fibrosis genes, increases in tumors relative to adjacent tissue, and predicts “wound that heals”–type survival only for liver cancer—albeit intertumor comparisons show no correlation without adjacent referencing. Scaling thus identifies and characterizes fundamental gene-gene interrelationships.
Tailoring of electronic and surface structures boosts exciton-triggering photocatalysis for singlet oxygen generation
Authors: Zhang Dongpeng , Wang Pengfei , Wang Junhui , Li Yanxiao , Xia Yuguo , Zhan Sihui
Published: November 2021

Significance

As the dielectric confinement effects in ultrathin two-dimensional photocatalysts, excitonic effects originating from the Coulomb interactions between photogenerated electrons and holes can be significantly promoted, which would endow the systems with distinct photoexcitation scenarios. A significant challenge is achieving nontrivial excitonic regulation, especially for inorganic semiconductors, to efficiently use solar energy. This research presents a strategy of modifications in both electronic and surface structures caused by surface Pt dopants to enhance the propensity to generate
1
O
2
by triplet energy transfer. This design concept highlights a promising exciton control strategy in two-dimensional inorganic semiconductors and demonstrates the importance of impurity states in the energy transfer process.
Vitexin inhibits APEX1 to counteract the flow-induced endothelial inflammation
Authors: Zhao Chuan-Rong , Yang Fang-Fang , Cui Qinghua , Wang Dong , Zhou Yiran , Li Yi-Shuan , Zhang Yun-Peng , Tang Run-Ze , Yao Wei-Juan , Wang Xiaohong , Pang Wei , Zhao Jia-Nan , Jiang Zhi-Tong , Zhu Juan-Juan , Chien Shu , Zhou Jing
Published: November 2021

Significance

This work identifies apurinic/apyrimidinic endonuclease1 (APEX1) as a shear stress-sensitive molecule that plays a crucial role in the atherogenic flow-induced endothelial proinflammatory responses. Depletion of endothelial Apex1 in mice ameliorated atherogenesis. We demonstrate that vitexin, a natural flavonoid, can inhibit the activation of APEX1 to protect vascular endothelium against the adverse effects of atherogenic stimuli. Mechanistically, vitexin associates directly with APEX1 to inhibit the atherogenic flow-induced interaction of APEX1 with acetyltransferase p300, its acetylation, and nuclear translocation. The action of APEX1 in the flow-evoked responses is dependent on NF-κB signaling. The translational significance of these findings is that targeting APEX1 with vitexin may represent a potential therapeutic strategy for the treatment endothelial inflammation and the related diseases.
Land and the limits of liberal legalism: property, transitional justice and non-reformist reforms in post-apartheid South Africa
Authors: Evans Matthew
Published: November 2021

Critical scholarship on transitional justice, in Africa and globally, has drawn attention both to limits of liberalism and legalism (such as inattention to structural injustices) and to normatively more expansive – transformative, and even revolutionary – approaches to justice. Focusing particularly on South Africa, this debate piece considers the roles of liberal property relations and conceptions of the rule of law in producing and maintaining injustices related to land and property in (post-)transitional societies in Africa and beyond. Moreover, the extent to which transitional justice might contribute to revolutionary aspirations of overcoming capitalist social and economic relations (as espoused, at least rhetorically, by liberation movements throughout Africa) is considered. It is suggested that while this is unlikely, non-reformist reforms offer one avenue by which more expansive (transformative or revolutionary) goals might be pursued, in part, in and through transitional justice.
GPCR signaling is highly compartmentalized in human cardiomyocytes and severely remodeled in atrial fibrillation
Authors: Beneke Kira , Pavlidou Nefeli Grammatika , Schäfer Andreas , Nikolaev Viacheslav O. , Molina Cristina E.
Published: November 2021

Atrial fibrillation (AF) has been linked to the remodeling of membrane receptors and alterations in downstream cAMP-dependent regulation. However, to date, no study has elucidated how the increase on cAMP upon different G-protein-coupled receptors (GPCRs) can lead to different physiological compartmentalized responses. The aim of this study was to investigate the compartmentally specific effects of GPCRs on cAMP levels in human atrial myocytes (HAMs) from patients with AF and control patients without AF (Ctl), and how these compartmentalized effects are altered in AF. HAMs were isolated from 60 AF and 76 Ctl patient tissues. Cells were transduced with adenoviruses (Epac1-camps, pm-Epac1-camps and Epac1-JNC) and cultured for 48 hours to express the FRET-based cAMP sensor in the cytosolic, membrane, and RYR2 nanodomains. Förster-resonance energy transfer (FRET) was used to measure cAMP levels in 525 HAMs stimulated with isoprenaline (100 µM), serotonin (100 µM), or the A2AR agonist CGS (200 nM). A desensitization to β-adrenergic receptor stimulation was exclusively found in the cytosol of AF myocytes, while no difference was seen in the RYR2 or LTCC compartment. Similar effects were observed upon serotonin stimulation with a significant desensitization in the cytosol, and no difference in the RYR2 compartment. In response to A2ARs stimulation AF myocytes displayed a significantly higher cytosolic increase in cAMP levels. However, no response was seen in the LTCC compartment in response to serotonin or A2AR stimulation. Collectively, our data show that cAMP levels are highly compartmentalized and differentially regulated by GPCRs. Furthermore, these results provide a mechanistic insight for the previously reported functional effects seen upon stimulation of these three receptors.
A hollow microlattice based ultralight active thermal control device and its fabrication techniques and thermal performances
Authors: Xu Wenjun , Liu Longquan , Chen Junming , Lv Xinying , Yao Yongtao
Published: November 2021

This paper introduces a new thermal control device (TCD) which has not only low weight and high efficiency but also passive and active cooling capabilities. The TCD mainly consists of hollow graphene-enhanced-metallic microlattice material, phase change material (PCM) and a peristatic pump. The PCM is inside the spatial-interconnected millimeter-scale diameter tubes, which are the basic constitution of the hollow microlattice material, in addition, the peristatic pump was connected with the tubes and used to force the liquid-state PCM to circulate inside the interconnected thin tubes. Thus, the proposed TCD takes combined advantages of the ultralight and high thermal transfer properties of the hollow graphene-enhanced-metallic microlattice materials, the thermal storage capability of the PCM and forced convection of the PCM driven by the peristatic pump as the PCM is in liquid state. The manufacturing process of the active TCD was also developed and proposed, which mainly includes additive manufacturing, composite electroless plating, polymer etching, liquid PCM injecting and the peristatic pump connecting. In addition to that, a thermal test system was built and the effective thermal conductivities of the TCD in passive cooling and with active cooling modes were experimentally studied. The TCD can absorb heat and actively dissipate heat by means of forced convection. Consequently, the proposed active TCD can be used to guarantee the electronic components and spacecrafts operate in a specific temperature range.
Electron beam-plasma discharge in GDT mirror trap: experiments on plasma start-up with electron gun
Authors: Soldatkina E.I. , Pinzhenin E.I. , Korobeynikova O.A. , Maximov V.V. , Yakovlev D.V. , Solomakhin A.L. , Savkin V.Ya. , Kolesnichenko K.S. , Ivanov A.A. , Trunev Yu.A. , Voskoboynikov R.V. , Shulzhenko G.I. , Annenkov V.V. , Volchok E.P. , Timofeev I.V. , Bagryansky P.A.
Published: November 2021

The paper describes experiments on the injection of an electron beam into a gas at the gas dynamic trap (GDT) and develops a technique for creating a starting plasma with parameters sufficient for its subsequent heating by neutral beams. It is found that a relatively thin electron beam is capable of ionizing plasma in the entire volume of the trap, and the plasma turbulence it excites is capable of accelerating some of the electrons to energies tens of times higher than the initial energy of the beam. It is shown that, in contrast to early experiments on tabletop open traps, collective beam relaxation under GDT conditions occurs in the vicinity of the entrance magnetic mirror. Since the electron cyclotron frequency in this region significantly exceeds the plasma frequency, it is necessary to study the mechanism of a beam-plasma discharge under these conditions. As a first step along this path, we measure the radial diffusion coefficient of fast particles, as well as the rate at which they gain energy.
Identifying the microtearing modes in the pedestal of DIII-D H-modes using gyrokinetic simulations
Authors: Hassan Ehab , Hatch D.R. , Halfmoon M.R. , Curie M. , Kotchenreuther M.T. , Mahajan S.M. , Merlo G. , Groebner R.J. , Nelson A.O. , Diallo A.
Published: November 2021

Recent evidence points toward the microtearing mode (MTM) as an important fluctuation in the H-mode pedestal for anomalous electron heat transport. A study of the instabilities in the pedestal region carried out using gyrokinetic simulations to model an ELMy H-mode DIII-D discharge (USN configuration, 1.4 MA plasma current, and 3 MW heating power) is presented. The simulations produce MTMs, identified by predominantly electromagnetic heat flux, small particle flux, and a substantial degree of tearing parity. The magnetic spectrogram from Mirnov coils exhibits three distinct frequency bands—two narrow bands at lower frequency (∼35–55 kHz and ∼70–105 kHz) and a broader band at higher frequency (∼300–500 kHz). Global linear GENE simulations produce MTMs that are centered at the peak of theω*profile and correspond closely with the bands in the spectrogram. The three distinctive frequency bands can be understood from the basic physical mechanisms underlying the instabilities. For example (i) instability of certain toroidal mode numbers (n) is controlled by the alignment of their rational surfaces with the peak in theω* profile, and (ii) MTM instabilities in the lowernbands are the conventional collisional slab MTM, whereas the highernband depends on curvature drive. While many features of the modes can be captured with the local approximation, a global treatment is necessary to quantitatively reproduce the detailed band gaps of the low-nfluctuations. Notably, the transport signatures of the MTM are consistent with careful edge modeling by SOLPS.
Overview of the Load-source Duality Modeling for Demand Side
Authors: Wang Xueying , Xue Yawei , Peng Dong , Zhao Lang , Liu Hongyang , Li Yizheng , Zhang Tianqi
Published: November 2021

With the increase of load and clean-green energy connect to the power system, big challenges are brought to the traditional control method of generation-follows-load (GFL). Therefore, it is important to study the load-follows-generation (LFG) models which can achieve active demand response by changing the load temporarily to reduce the difference between maximum and minimum load. This paper introduces the concept of LFG and GFL models, summarizes the difference between them and puts forward the concept of load-source duality at first. Then, introduces load response modeling, optimization objectives, constraints, scheduling methods and control methods of six LFG models based on the recent research results in this area. Each model can alleviate the pressure in maintaining stability on the generation side, improving the safety and reliability of the power system. Finally, this paper puts forward the future development trend of LFG models based on the overviews.
Single-phase-to-ground Fault Line Selection Method Based on STOA-SVM
Authors: Liu Yicen , Liu Xiaojiang , Fan Songhai , Ma Xiaomin , Deng Sijing
Published: November 2021

In view of the complex characteristics of nonlinearity and non-stableness of the zero-order current of each line after the single-phase ground fault of the distribution network, a distribution network fault selection method based on Sooty Tern Optimization Algorithm(STOA) and the combination of support vector machine is proposed. At first, the zero-sequence current before and after fault is obtained, then five kinds of IMFs including different components are obtained by ensemble empirical mode decomposition, and the energy entropy of the fault transient zero-sequence current is obtained by Hilbert transform, the results of training and testing are obtained by inputting the feature vector. The simulation results show that the accuracy of the proposed line selection model is 97.5%.
Improved UKF-SLAM with Lie Group Operation and Robust Feature Tracking for Motion Vehicles
Authors: Huang Xin , Liang Zuoxian , Zhang Kai , Liu Pingyuan
Published: November 2021

This paper proposes an improved simultaneous localization and mapping (SLAM) algorithm based on tightly coupled camera images and IMU data, which provides accurate and robust localization for autonomous vehicles and unmanned aerial vehicles (UAV), especially for those in GPS-denied environments. Many research efforts have demonstrated the effectiveness of fusing camera images and inertial data with the Unscented Kalman filter (UKF), but there is still one tricky problem about the non-linearity of the kinematics of rotations. To address this issue, we propose a novel UKF-SLAM approach by rebuilding system and measurement models based on the Lie group and Lie algebra, which obtains state estimates with reasonably high accuracy. Besides, we also offer a new method to handle corner matching outliers, which only causes slightly additional computation costs but eliminates outliers and enhances corner tracking robustness. Results from extensive experimental data have validated the effectiveness of the proposed approach, and this method also achieves comparable precision to the state-of-art.
Research on Intelligent Control System Based on Feature Recognition
Authors: Wu Jinghong , Liu Qian , Chen Jian
Published: November 2021

Fountain is an important facility in modern landscape art. Ordinary fountains are regulated by water valves, which makes the water column of the fountain very high, so the height of the fountain cannot be changed flexibly, the fountain is the product of the combination of the most popular garden architecture and appreciation in recent years. In this paper, intelligent control system based on feature recognition is designed. According to the system, fountain forms and features can be recognized automatically. At the same time, the system can also be integrated with computer animation, which makes the melody, emotion, rhythm and waterscape art to realize harmonious and unified.
Research on Aging Resistance of Three Phase Composites for Anti-collision Intelligent Control of Bridge Engineering
Authors: Wang Jifeng , Guan Liangchao , Ge Jing
Published: November 2021

Aminated Carbon Nanotubes (CNTs) and Carbon Fiber (CF) materials for anticollision intelligent control of Bridge Engineering were used to enhance the properties of Bismaleimide Resin (BMI) matrix resin and then tested the moist heat aging, salt spray aging and erosion resistance in this study. The resulted show that when the aging time was 168h, after wet heat and salt spray, the flexural strength and impact strength of three-phase composites with 1.5wt% MWNTs-NH2 content can reach maximum, and the wet heat aging bending performance is 45% better than that of non-added carbon nanotubes, the impact performance is 41% higher, the salt spray aging bending performance is 43% higher and the salt spray aging impact performance is 32% higher.