bluuebunny/crossref_metadata_2025 huggingface dataset:
Nonvolatile modulation of spin transport in PMN-PT/LiFe5O8/Pt multiferroic heterostructures
Authors: Chen Shiwei , Cao Cuimei , Shen Lvkang , Liu Ming , Jiang Changjun , Zhan Qingfeng , Qiu Xuepeng
Published: December 2021

Beside playing a keystone role in spin-field-effect transistor, electrical control of spin transport is also of fundamental and practical importance for many other spintronic devices due to the advantages of energy efficiency and versatility. In this work, we demonstrate a significant electrical modulation of spin transport in the PMN-PT/LiFe5O8/Pt heterostructures. The key spin transport parameters, including the spin Hall angle, spin diffusion length, and spin mixing conductance, were extracted through the thickness dependence of spin Hall magnetoresistance. It is found that the spin Hall angle decreases with the decrease in temperature, while the spin diffusion length keeps invariant with temperature, revealing the dominance of D'yakonov–Perel' type spin transport in LiFe5O8/Pt. Remarkably, by applying the electric field onto the piezoelectric PMN-PT substrate, the spin Hall angle of Pt can be modulated 28% and exhibits a nonvolatile hysteresis relationship with the applied electric field, which primarily originates from the modulation of Pt resistivity induced by the strain coupling through the ferroelastic domain switching of the ferroelectric PMN-PT substrate. Our results elucidate the spin transport characteristics in PMN-PT/LiFe5O8/Pt heterostructures and pave the way toward novel spintronic devices with electrically tunable spin current generation and transport processes.
Thermodynamically consistent generalized hydrodynamic theory of thermal conduction and integral equations of thermal conductivity of simple fluids in electromagnetic fields
Authors: Eu Byung
Published: December 2021

We have reviewed thermodynamically consistent evolution equations of fluids in an invited review article in the McGill University bicentennial memorial issue [B. C. Eu, Can. J. Chem. (in press) (2021)]. In this article, we apply the generalized hydrodynamic evolution equations of heat fluxes to derive integral equations for thermal conductivity coefficients of fluids in electromagnetic fields, which generalize the linear response theory formula of Green and Kubo to nonlinear heat conduction phenomena. The constitutive equation for the temperature field derived is compared with the temperature evolution equation obtained by Guo et al. [Physica D 342, 24 (2017)] on the basis of extended irreversible thermodynamics. They are considerably different.
Voltage-controlled precision electronic power regulator
Authors: Rutin S. B.
Published: December 2021

The architecture of a novel electronic power regulator, which allows a set value of constant power on a wire probe to be maintained, is presented. A gain in the negative feedback loop of ≈2 · 103 allows the set power value in the series of pulses to be accurately maintained at the level of 99.95% (proximity 0.05). In order to study short term processes, the response time of the described regulator is in the order of 2 μs. The created architecture is easily scalable for various tasks, ranging from the well-known transient hot-wire method to other applications, examples of which are given in this article (unsteady heat transfer in supercritical-pressure fluids and unstable mixtures having lower critical solution temperature). A comparison of the presented controller architecture with the previously described solutions from the point of view of operational stability is given.
A comparison of Boltzmann and Gibbs definitions of microcanonical entropy for small systems
Authors: Shirts Randall B.
Published: December 2021

Two different definitions of entropy, S = k ln W, in the microcanonical ensemble have been competing for over 100 years. The Boltzmann/Planck definition is that W is the number of states accessible to the system at its energy E (also called the surface entropy). The Gibbs/Hertz definition is that W is the number of states of the system up to the energy E (also called the volume entropy). These two definitions agree for large systems but differ by terms of order N−1 for small systems, where N is the number of particles in the system. For three analytical examples (a generalized classical Hamiltonian, identical quantum harmonic oscillators, and the spinless quantum ideal gas), neither the Boltzmann/Planck entropy nor heat capacity is extensive because it is always proportional to N − 1 rather than N, but the Gibbs/Hertz entropy is extensive and, in addition, gives thermodynamic quantities, which are in remarkable agreement with canonical ensemble calculations for systems of even a few particles. In a fourth example, a collection of two-level atoms, the Boltzmann/Planck entropy is in somewhat better agreement with canonical ensemble results. Similar model systems show that temperature changes when two subsystems come to thermal equilibrium are in better agreement with expectations for the Gibbs/Hertz temperature than for the Boltzmann/Planck temperature, except when the density of states is decreasing. I conclude that the Gibbs/Hertz entropy is more useful than the Boltzmann/Planck entropy for comparing microcanonical simulations with canonical molecular dynamics simulations of small systems.
An integrated widefield probe for practical diamond nitrogen-vacancy microscopy
Authors: Abrahams G. J. , Scholten S. C. , Healey A. J. , Robertson I. O. , Dontschuk N. , Lim S. Q. , Johnson B. C. , Simpson D. A. , Hollenberg L. C. L. , Tetienne J.-P.
Published: December 2021

The widefield diamond nitrogen-vacancy (NV) microscope is a powerful instrument for imaging magnetic fields. However, a key limitation impeding its wider adoption is its complex operation, in part due to the difficulty of precisely interfacing the sensor and sample to achieve optimum spatial resolution. Here, we demonstrate a solution to this interfacing problem that is practical and reliably minimizes NV-sample standoff. We built a compact widefield NV microscope, which incorporates an integrated widefield diamond probe with full position and angular control, and developed a systematic alignment procedure based on optical interference fringes. Using this platform, we imaged an ultrathin (1 nm) magnetic film test sample and conducted a detailed study of the spatial resolution. We reproducibly achieved an estimated NV-sample standoff (and hence spatial resolution) of at most ∼2 μm across a ∼0.5 mm field of view. Guided by these results, we suggest future improvements for approaching the optical diffraction limit. This work is a step toward realizing a widefield NV microscope suitable for routine high-throughput mapping of magnetic fields.
PT symmetric dynamics in counter-rotating gyroscopic mechanical systems
Authors: Dong Bin , Shi Chengzhi , Parker Robert G.
Published: December 2021

Parity-time (PT) symmetry was first studied in quantum mechanical systems with a non-Hermitian Hamiltonian whose observables are real-valued. Most existing designs of PT symmetric systems in electronics, optics, and acoustics rely on an exact balance of loss and gain in the media to achieve PT symmetry. However, the dispersive behavior of most loss and gain materials restricts the frequency range where the system is PT symmetric. This makes it challenging to access the exceptional points of the system to observe the PT symmetric transition dynamics. Here, we propose a new path to realize PT symmetric systems based on gyroscopic effects instead of using loss and gain units. We demonstrate that PT symmetry and the occurrence of exceptional points are preserved for inversive, counter-rotating gyroscopic systems even with dispersive sub-units. In a gyroscopic system with two circular rings rotating in opposite directions at the same speed, the spontaneous symmetry breaking across the exceptional points results in a phase transition from a moving maximum deformation location to a motionless maximum point. The motionless maximum point occurs despite the externally imposed rotation of the two rings. The results set the foundation to study nonlinear dispersive physics in PT symmetric systems, including solitary waves and inelastic wave scattering.
Ultra-thin AlGaN/GaN HFET with a high breakdown voltage on sapphire substrates
Authors: Liang Zhiwen , Du Hanghai , Yuan Ye , Wang Qi , Kang Junjie , Zhou Hong , Zhang Jincheng , Hao Yue , Wang Xinqiang , Zhang Guoyi
Published: December 2021

In this Letter, an ultra-thin AlGaN/GaN heterostructure field effect transistor (HFET) with a total thickness of ∼200 nm was fabricated on sapphire substrates by combing physical vapor deposition and metal organic chemical vapor deposition growth methods. Thanks to the absence of a conventional semi-insulating thick GaN buffer by taking advantage of an ex situ sputtered AlN nucleation layer, we achieved a profound soft breakdown voltage of 1700 V accompanied by a 12.5 Ω·mm on-resistance and a low off-state leakage of 0.1 μA/mm in such ultra-thin HFET devices. Our work demonstrates an alternative strategy to fabricate GaN based power devices with high breakdown voltage and low cost.
Metallic waveguide transmitarrays for dual-band multibeam terahertz antennas
Authors: Liang Jiaxuan , Ning Tingyin , Fan Jiayu , Zhang Min , Su Hong , Zeng Yu-Jia , Liang Huawei
Published: December 2021

A metallic waveguide transmitarray antenna (MWTA) is proposed to attain dual-band multibeams with high gain in the terahertz (THz) range, which is realized by independently controlling the phases of the two bands with orthogonal polarizations simultaneously. The phase distribution of each polarization on the MWTA for attaining the corresponding multibeam radiation pattern is calculated by using the Gerchberg–Saxton algorithm based on Fresnel diffraction theory. Furthermore, the phase delay of each unit cell is adjusted by varying the waveguide dimension to achieve the corresponding phase distributions. As a proof of concept, a dual-band MWTA with a diameter of 48 mm is designed and simulated to transform plane waves into triple beams at 0.14 THz and dual beams at 0.1 THz, respectively. Their peak gains are ∼30 and ∼28 dBi and the aperture efficiencies are 67% and 56%, respectively. Their 1 dB gain bandwidths can reach 10 GHz (136.5–146.5 GHz) and 11 GHz (94.7–105.6 GHz), respectively. The measured far-field results agree well with the simulations. The proposed dual-band THz antennas are very promising for applications in wireless and satellite communications.
Path integral simulations of confined parahydrogen molecules within clathrate hydrates: Merging low temperature dynamics with the zero-temperature limit
Authors: Schmidt Matthew , Millar Jayme , Roy Pierre-Nicholas
Published: December 2021

Clathrate hydrates, or cages comprised solely of water molecules, have long been investigated as a clean storage facility for hydrogen molecules. A breakthrough occurred when hydrogen molecules were experimentally placed within a structure-II clathrate hydrate, which sparked much interest to determine their feasibility for energy storage [Mao et al., Science 297, 2247–2249 (2002)]. We use Path Integral Molecular Dynamics (PIMD) and Langevin equation Path Integral Ground State (LePIGS) for finite temperature and zero-temperature studies, respectively, to determine parahydrogen occupancy properties in the small dodecahedral (512) and large hexakaidecahedral (51264) sized cages that comprise the structure-II unit cell. We look at energetic and structural properties of small clusters of hydrogen, treated as point-like particles, confined within each of the different sized clathrates, and treated as rigid, to determine energetic and structural properties in the zero-temperature limit. Our predicted hydrogen occupancy within these two cage sizes is consistent with previous literature values. We then calculate the energies as a function of temperature and merge the low temperature results calculated using finite temperature PIMD with the zero-temperature results using LePIGS, demonstrating that the two methods are compatible.
BiGlobal stability analysis of planar fountains
Authors: Srinivasan Kumanan , Shrimali Uttam Sunilbhai , Vinoth B. R.
Published: December 2021

The linear BiGlobal stability analysis is used to investigate the transition from a globally stable state to a globally unstable state (flapping oscillation) in planar fountains (negatively buoyant jets). The critical conditions for the onset of flapping oscillation and its corresponding frequency are predicted using global stability analysis for fountains with a jet-to-ambient density ratio of 0.95. The results from the global stability analysis are favorably compared with unsteady numerical simulations and the available experiments in the literature.
Magnetoelectric effect in a flexible heterostructure comprising magnetostrictive fiber composite and piezopolymer PVDF
Authors: Fetisov Leonid Y. , Saveliev Dmitriy V. , Dzhaparidze Mikhail V. , Musatov Vladimir I. , Fetisov Yuri K.
Published: December 2021

Linear and nonlinear magnetoelectric (ME) effects in flexible composite heterostructures comprising layers of magnetostrictive fiber composite (MFC) and poly(vinylidene fluoride) (PVDF) piezopolymer have been observed and investigated. MFC consists of a set of Ni-wires with a diameter of 100, 150, or 200 μm arranged in parallel close to each other in one layer and placed in a polymer matrix. The structure was excited by an ac magnetic field in the frequency range of 1–15 kHz and simultaneously magnetized in the plane by a dc field H. The voltage generated by the PVDF layer was recorded at the frequency of the structure bending resonance. The ME coefficient of 5.8 V/(Oe cm) was obtained for a heterostructure with Ni-wires 150 μm in diameter at a frequency of 5.1 kHz when magnetized along the wires. The ME effect magnitude depends on the H-field orientation relative to the Ni-wires due to the magnetostriction anisotropy arising from demagnetization effects. The generation of ME voltage second harmonic with an efficiency of 26 mV/(Oe2·cm) was observed in the heterostructure with an increase in the excitation field.
A partially linearized spin-mapping approach for simulating nonlinear optical spectra
Authors: Mannouch Jonathan R. , Richardson Jeremy O.
Published: December 2021

We present a partially linearized method based on spin-mapping for computing both linear and nonlinear optical spectra. As observables are obtained from ensembles of classical trajectories, the approach can be applied to the large condensed-phase systems that undergo photosynthetic light-harvesting processes. In particular, the recently derived spin partially linearized density matrix method has been shown to exhibit superior accuracy in computing population dynamics compared to other related classical-trajectory methods. Such a method should also be ideally suited to describing the quantum coherences generated by interaction with light. We demonstrate that this is, indeed, the case by calculating the nonlinear optical response functions relevant for the pump–probe and 2D photon-echo spectra for a Frenkel biexciton model and the Fenna–Matthews–Olsen light-harvesting complex. One especially desirable feature of our approach is that the full spectrum can be decomposed into its constituent components associated with the various Liouville-space pathways, offering a greater insight beyond what can be directly obtained from experiments.
Distinctive ionic transport of freshly excised human epileptogenic brain tissue
Authors: Emin David , Fallah Aria , Salamon Noriko , Mathern Gary , Akhtari Massoud
Published: December 2021

Epileptogenic lesions have higher concentrations of sodium than does normal brain tissue. Such lesions are palpably recognized by a surgeon and then excised in order to eliminate epileptic seizures with their associated abnormal electrical behavior. Here, we study the frequency-dependent electrical conductivities of lesion-laden tissues excised from the brains of epilepsy patients. The low-frequency (<1000 Hz) conductivity of biological tissue primarily probes extracellular solvated sodium-cations traveling parallel to membranes within regions bounded by blockages. This conductivity rises monotonically toward saturation as the frequency surpasses the rate with which diffusing solvated sodium cations encounter blockages. We find that saturation occurs at dramatically higher frequencies in excised brain tissue containing epileptogenic lesions than it does in normal brain tissue. By contrast, such an effect is not reported for tumors embedded in other excised biological tissue. All told, epileptogenic lesions generate frequency-dependent conductivities that differ qualitatively from those of both normal brain tissues and tumors.
Genome evolution in an agricultural pest following adoption of transgenic crops
Authors: Taylor Katherine L. , Hamby Kelly A. , DeYonke Alexandra M. , Gould Fred , Fritz Megan L.
Published: December 2021

Significance

Evolution of resistance to management approaches in agricultural landscapes is common and results in economic losses. Early detection of pest resistance prior to significant crop damage would benefit the agricultural community. It has been hypothesized that new genomic approaches could track molecular signals of emerging resistance and trigger efforts to preempt widespread damage. We tested this hypothesis by quantifying genomic changes in the pestHelicoverpa zeaover a 15-y period concurrent with commercialization of transgenicBacillus thuringiensis–expressing crops and their subsequent loss of efficacy. Our results demonstrate the complex nature of evolution in agricultural ecosystems and provide insight into the potential and pitfalls of using genomic approaches for resistance monitoring.
Cytoglobin has potent superoxide dismutase function
Authors: Zweier Jay L. , Hemann Craig , Kundu Tapan , Ewees Mohamed G. , Khaleel Sahar A. , Samouilov Alexandre , Ilangovan Govindasamy , El-Mahdy Mohamed A.
Published: December 2021

Significance

We identified a novel function of cytoglobin (Cygb) as an efficient superoxide dismutase (SOD) with a high–bimolecular dismutation rate on the order of 10
8
M
−1
⋅ s
−1
. It is the first Fe-centered SOD identified in mammalian cells and the only member of the globin family shown to have potent SOD activity. This SOD function of Cygb may serve to explain the prior reports of its antioxidative activity and the toxicities and disease seen with its genetic deletion, including the increased incidence of tumors. Combined with its potent NO dioxygenase activity, Cygb would be highly effective in decreasing both O
2
•−
and NO levels, serving to decrease the formation of peroxynitrite and secondary oxidative injury.
Late Pleistocene shrub expansion preceded megafauna turnover and extinctions in eastern Beringia
Authors: Monteath Alistair J. , Gaglioti Benjamin V. , Edwards Mary E. , Froese Duane
Published: December 2021

Significance

Megafauna strongly influence vegetation structure, and population declines can alter ecosystem functioning. Overhunting of grazing megafauna is argued to have driven the collapse of widespread, northern steppe-tundra and its replacement by woody vegetation at the end of the ice age. However, in Alaska and Yukon, mammoth and horse became extinct around the time that steppe-tundra was replaced by shrub tundra, leaving it unclear whether this vegetation change caused, or was caused by, reduced megafauna populations. Comparison of accurately dated pollen records with a radiocarbon-dated bone chronology shows that shrubs began expanding before grazer populations declined. This indicates that climate was the primary control of steppe-tundra persistence and that climate-driven vegetation change may pose threats to faunal diversity in the future.
The effectiveness of China’s regional carbon market pilots in reducing firm emissions
Authors: Cui Jingbo , Wang Chunhua , Zhang Junjie , Zheng Yang
Published: December 2021

Significance

The emission trading system (ETS) is an important policy instrument for China to achieve its climate targets. However, the effectiveness of ETS in emission reductions and its economic consequences are unknown. Using a unique dataset of firm tax records, we comprehensively assess the impacts of China’s regional ETS pilots, taking advantage of the policy experiments in certain sectors across seven jurisdictions. We demonstrate unambiguous evidence that China’s ETS leads to a reduction in carbon emissions despite low carbon prices and infrequent trading. We also identify the channels through which firms respond to ETS by adjusting energy consumption and sources, employment, capital, and productivity. The lessons learned from the regional pilots shed light on the design of China’s national carbon ETS.
Coxiella burnetii
inhibits host immunity by a protein phosphatase adapted from glycolysis
Authors: Zhang Yong , Fu Jiaqi , Liu Shuxin , Wang Lidong , Qiu Jiazhang , van Schaik Erin J. , Samuel James E. , Song Lei , Luo Zhao-Qing
Published: December 2021

Significance

Many effectors of the
Coxiella burnetii
Dot/Icm transporter are important for its virulence, but the lack of understanding of their biochemical activity prevents the use of them as potential therapeutic targets. Here, we found that the effector Cbu0513 (CinF) is a protein phosphatase that attacks IκBα, a key regulatory protein in NF-κB signaling. Unlike its homologs such as ST0318 from the archaeon
Sulfolobus tokodaii
, CinF has lost the enzymatic activity as a fructose-1,6-bisphosphate aldolase/phosphatase. Instead, it specifically targets IκBα to make it resistant to proteasome-mediated degradation in cells stimulated with NF-κB agonists. Our finding has expanded the strategy used by bacterial pathogens to inhibit host immunity, which may provide leads for the development of immune modulators for disease treatment.
The role of non–COVID-specific and COVID-specific factors in predicting a shift in willingness to vaccinate: A panel study
Authors: Jamieson Kathleen Hall , Romer Daniel , Jamieson Patrick E. , Winneg Kenneth M. , Pasek Josh
Published: December 2021

Significance

In communities that remain below the immunity threshold needed to blunt COVID-19’s spread, SARS-CoV-2 has a greater chance of mutating to evade vaccines. This study underscores the central role of trust and knowledge in increasing the likelihood of vaccinating. Trust in scientific institutions and spokespersons anchors time 1 vaccination intentions and knowledge affects them at both times 1 and 2. These background (non–COVID-specific) factors as well as flu vaccination history and patterns of media reliance played a more prominent role in shifting individuals from vaccination hesitance to acceptance than did COVID-specific ones. The study underscores the need for ongoing community engagement and trust building, proactive communication about vaccination, motivating vaccination against seasonal flu, and deploying science-consistent, provaccination voices across media.
Photodissociation of dicarbon: How nature breaks an unusual multiple bond
Authors: Borsovszky Jasmin , Nauta Klaas , Jiang Jun , Hansen Christopher S. , McKemmish Laura K. , Field Robert W. , Stanton John F. , Kable Scott H. , Schmidt Timothy W.
Published: December 2021

Significance

It has long been observed that the coma of a comet is often green while its tail is not. While the explanation for this must be that the molecules responsible for the green emission, C
2
, are photodissociated, the mechanism was, until now, unknown. We have observed the photodissociation of C
2
in the laboratory for the first time and, in doing so, have determined its bond dissociation energy with unprecedented precision. Invoking the observed mechanism, the calculated lifetime of cometary C
2
is found to be consistent with astronomical observations.
Leveraging cell-type-specific regulatory networks to interpret genetic variants in abdominal aortic aneurysm
Authors: Ma Shining , Chen Xi , Zhu Xiang , Tsao Philip S. , Wong Wing Hung
Published: December 2021

Significance

Abdominal aortic aneurysm (AAA) is a common and severe disease with major genetic risk factors. In this study we generated enhancer-promoter contact data to identify regulatory elements in AAA-relevant cell types and identified changes in their predicted chromatin accessibility between AAA patients and controls. We integrated this information with disease-associated variants in regulatory elements and gene bodies to further understand the etiology and pathogenetic mechanisms of AAA. Our study combined whole-genome sequencing data with gene regulatory relations in disease-relevant cell types to reveal the important roles of the interleukin 6 pathway and
ERG
and
KLF
regulation in AAA pathogenesis.
Mechanism of shaping membrane nanostructures of endoplasmic reticulum
Authors: Zucker Ben , Kozlov Michael M.
Published: December 2021

Significance

A highly intricate architecture of endoplasmic reticulum (ER) membrane is crucial for the organelle functioning. Recent super-resolution microscopy studies discovered a nanoscopic level of ER organization characterized by 10- to 100-nm internal length scales. Deciphering the physical mechanisms of forming the ER nanostructures is a base for understanding the cell control of ER dynamics. Here, we proposed and computationally substantiated a common mechanism of shaping of all currently known ER nanostructures based on the intrinsic membrane curvature and ultra-low tensions as, respectively, a primary and a modulating factor.
Asymptotic symmetries at null-infinity for the Rarita–Schwinger field with magnetic term
Authors: Tomova Bilyana L
Published: December 2021

In this paper we study the magnetic charges of the free massless Rarita–Schwinger field in four dimensional asymptotically flat space-time. This is the first step towards extending the study of the dual BMS charges to supergravity. The magnetic charges appear due to the addition of a boundary term in the action. This term is similar to the theta term in Yang–Mills theory. At null-infinity an infinite dimensional algebra is discovered, both for the electric and magnetic charge.
Phase composition, morphology, properties and improved catalytic activity of hydrothermally-derived manganese-doped ceria nanoparticles
Authors: Kurajica S , Ivković I K , Dražić G , Shvalya V , Duplančić M , Matijašić G , Cvelbar U , Mužina K
Published: December 2021

Manganese-doped ceria nanoparticles were prepared by hydrothermal synthesis and the prepared samples were thermally treated at 500 °C for 2 h. The samples were investigated using x-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), energy-dispersive x-ray spectroscopy (EDS), N2 adsorption and x-ray photoelectron spectroscopy (XPS). XRD revealed that nanocrystalline ceria is the main phase in all samples, while a romanechite-like phase (Na2Mn5O10) appears in the sample doped with 30% of Mn. TEM coupled with EDS exposed the presence of the same phase in the sample doped with 20% Mn. While ceria particles have spherical morphology and particle size ranging from 4.3 to 9.2 nm, the rare crystals of the romanechite-like phase adopt a tubular morphology with a length of at least 1 μm. However, the decrease in the ceria lattice constant and the EDS spectra of the ceria nanoparticles clearly indicate that a substantial amount of manganese entered the ceria crystal lattice. Manganese doping has a beneficial impact on the specific surface area of ceria. XPS measurements reveal a decrease in the Ce3+/Ce3+ + Ce4+ content in the doped samples which is replaced by Mn3+. Moreover, a drastic increase in adsorbed oxygen is observed in the doped samples which is the consequence of the increase in Mn3+ species that promotes oxygen migrations to the surface of the sample. Compared to the pure sample, the doped samples showed significantly higher catalytic activity for the process of toluene oxidation.
Network Analysis to Determine the Optimal Route for Firefighters in Makassar City
Authors: Widyantoro Bimo Aji , Santosa Purnama Budi
Published: December 2021

Makassar city experiences many residential fire disasters during the last years. One of the causes of fires is difficult to overcome due to the firefighters’ late response. The number of fires occurred due to the ineffectiveness of the fire fighting road, obstructed by traffic conditions, in its operation. Developing a geospatial route analysis can help firefighters quickly find the best route to a fire point to overcome this problem. Geospatial route analysis is currently a key role in emergency responses for urban fire disasters. A routing system can provide network analysis that allows users to navigate between source and destination points. In this case, the system can help firefighters to arrive as quickly as possible. On complicated road networks, some impedance factors would slow down drivers on a particular road. This study aims to provide firefighters from the base stations to residential fire disaster locations. The method used in the studies is Dijkstra’s algorithms to calculate weights of the impedance factors to optimal routing based on length of the road, speed drive, and traffic conditions. Implementation of routing analysis using open source geospatial software, PostgreSQL as database management system with PostGIS, and pgrouting as extensions. The modeling results show that the optimal route selection with speed parameters based on road classification has a low weight value. Therefore, it can be used as a reference for selecting a firefighter’s routing.
Analysis of accuracy comparison tidal global (FES2014, TPXO9) and regional (BIG Prediction) models to the existing tides in Surabaya and surrounding waters
Authors: Khomsin  , Pratomo D G , Rohmawati C N
Published: December 2021

Tidal data has a significant role in various fields in hydrographic surveys and navigation, port planning, and other coastal management. The number of fixed tide stations in Indonesia is minimal compared to the vast territorial waters in Indonesia. So that for areas that are not covered by tidal fixed stations, direct tidal observation with a certain length of observation is necessary, and of course, this requires quite expensive costs. Fortunately, there are regional and global tidal data predictions that can be used to determine tidal conditions in Indonesian waters. In this study, the regional (BIG) and the global (FES2014 and TPXO9) tidal data prediction models were validated with direct observation in the five locations such as Surabaya, Gresik1, Gresik2, Bangkalan, and Giligenting for 39 hours. The root means square error (rmse) calculation results show that in the five locations, the BIG tidal prediction has the smallest rmse value in three tidal stations at Gresik 1, Gresik 2, and Gili Genting with 0.303 m, 0.050 m, and 0.155 m respectively. At the same time, the TPXO9 tidal model shows the biggest rmse at Gresik 1, Gresik 2, and Bangkalan with 0.420 m, 0.195 m, and 0.630 m, respectively.
Approximate decoherence free subspaces for distributed sensing
Authors: Hamann Arne , Sekatski Pavel , Dür Wolfgang
Published: December 2021

We consider the sensing of scalar valued fields with specific spatial dependence using a network of sensors, e.g. multiple atoms located at different positions within a trap. We show how to harness the spatial correlations to sense only a specific signal, and be insensitive to others at different positions or with unequal spatial dependence by constructing a decoherence-free subspace for noise sources at fixed, known positions. This can be extended to noise sources lying on certain surfaces, where we encounter a connection to mirror charges and equipotential surfaces in classical electrostatics. For general situations, we introduce the notion of an approximate decoherence-free subspace, where noise for all sources within some volume is significantly suppressed, at the cost of reducing the signal strength in a controlled way. We show that one can use this approach to maintain Heisenberg-scaling over long times and for a large number of sensors, despite the presence of multiple noise sources in large volumes. We introduce an efficient formalism to construct internal states and sensor configurations, and apply it to several examples to demonstrate the usefulness and wide applicability of our approach.
Factors influencing household-level positive and negative solid waste management practices in rapidly urbanizing cities: insights from Santa Cruz de la Sierra, Bolivia
Authors: Lozano Lazo Denise P , Gasparatos Alexandros
Published: December 2021

Household solid waste management (HSWM) practices are a critical aspect of municipal solid waste management (MSWM) systems. Despite efforts to implement source separation and recycling at the household level in developing countries, negative practices such as illegal dumping and backyard burning remain ubiquitous, particularly in rapidly urbanizing cities. Source separation and recycling behaviors have been rarely studied in such cities. Moreover, studies on illegal dumping and backyard burning using robust tools and frameworks are practically non-existent. This study aims to (a) estimate the prevalence of ‘negative’ and ‘positive’ behaviors for different HSWM practices, and (b) identify their observable and non-observable influencing factors. The focus is Santa Cruz, a rapidly urbanizing city of Bolivia. Household surveys (n = 305) are used to establish the connections between latent constructs (e.g. awareness, satisfaction), and observable variables (e.g. location, socio-demographic characteristics) with each behavior. This is achieved through the combination of exploratory factor analysis to validate the constructs to be included in the analysis, and structural equation modeling to identify the most influential factors. Two causal models are developed, one for the positive behaviors (i.e. source separation, recyclables donation, recyclables selling, and use of drop-off facilities), and the other for the negative behaviors (i.e. illegal dumping and backyard burning). Results indicate that, satisfaction with the MSWM service has a negative and significant influence on the prevalence of illegal dumping and backyard burning behaviors, while the remoteness of the household (i.e. distance to the city center) has a positive significant effect on the prevalence of these behaviors. Source separation and recyclable donation are influenced positively by latent constructs such as attitudes, knowledge, and awareness. For recyclables selling and use of drop-off stations, income and location are the most relevant factors, although with smaller effects.
Chemometric and DoE-Based Analytical Quality Risk Management to HPTLC Method for Simultaneous Estimation of Metronidazole and Norfloxacin
Authors: Prajapati Pintu B , Patel Payal R , Shah Shailesh A
Published: December 2021

According to the upcoming ICH Q14 guideline, the development of an analytical method by the implementation of the AQbD approach based on analytical quality risk management and design of experiments will become a regulatory requirement for the registration of new drug substances and products. In literature, the HPTLC method has not been reported yet for simultaneous estimation of metronidazole and norfloxacin. Hence, the robust HPTLC method has been developed and validated for simultaneous estimation of metronidazole and norfloxacin using QRM and the DoE-based enhanced AQbD approach. The principal component analysis was applied for chemometric-based risk assessment of method risk parameters. The high-risk method parameters were optimized by a DoE-based full-factorial design. The MODR and control strategy was estimated for quality risk management throughout the lifecycle of the HPTLC method. The HPTLC method was developed using silica gel 60 F254 as stationary phase and acetonitrile-methanol-formic acid-ammonia (9.5 + 0.5 + 0.5 + 0.3, v/v) as mobile phase. The developed method was validated as per ICH Q2 (R1) guideline. The developed method was applied for the assay of combined pharmaceutical dosage forms of metronidazole and norfloxacin and results were found in compliance with their respective labeled claim.
Sex Difference and Interaction of SIRT1 and FOXO3 Candidate Longevity Genes on Life Expectancy: A 10-Year Prospective Longitudinal Cohort Study
Authors: Ji John S , Liu Linxin , Shu Chang , Yan Lijing L , Zeng Yi
Published: December 2021

SIRT1 and FOXO3 are both associated with longevity. Molecular biology research in many organisms (yeast, nematode worm Caenorhabditis elegans, and mice mammalian models) shows SIRT1 acts on the FOXO family of forkhead transcription factors to respond to oxidative stress better, shifting processes away from cell death toward stress resistance. Human population studies need epidemiologic evidence. We used an open cohort of 3 166 community-dwelling participants in China with follow-up from 2008 to 2018. The mean age at baseline was 84.6 years. In 16 375 person-years of follow-up, there were 1 968 mortality events. SIRT1 and FOXO3 exhibited Mendelian randomization as there was no correlation with each other and with baseline study population characteristics. Some SIRT1 and FOXO3 single-nucleotide polymorphisms showed protective effects for mortality risk. The FOXO3 protective effect was stronger in females, and the SIRT1 protective effect was stronger in male study participants. We did not see evidence of a synergistic effect of being carriers of both SIRT1 and FOXO3 advantageous alleles.
Trans-dimensional imaging of the random inhomogeneity structure in the southern Ryukyu arc, Japan
Authors: Takahashi Tsutomu , Kaiho Yuka , Ishihara Yasushi , Obana Koichiro , Miura Seiichi , Kodaira Shuichi , Kaneda Yoshiyuki
Published: December 2021

The seismic velocity structure of the lithosphere shows various inhomogeneities over a wide range of scales, and such inhomogeneity causes complex seismic waves above a few hertz due to multiple scattering. Medium around active volcanoes and large faults tends to show strong random inhomogeneity in relatively small areas. For a more precise understanding of such random velocity inhomogeneities, it is necessary to estimate their detailed spatial variation without smoothing constraints. This study introduces a trans-dimensional approach for the 3-D imaging of random inhomogeneity using the reversible jump Markov chain Monte Carlo (rjMCMC) method, and set the number of structural parameters and their spatial layout as unknown parameters. Since the scale dependence of the random inhomogeneity is related to the frequency dependence of seismic wave scattering, the covariance matrix of the likelihood function was defined to be non-diagonal so that residuals at different frequencies in each ray path are correlated. A synthetic test showed this covariance matrix worked adequately for estimating parameters of a power-law-type spectrum of random inhomogeneity. Analysis of seismic data at the southern Ryukyu arc in the southwest Japan found anomalies with strong and weak inhomogeneities. A strongly inhomogeneous band with a width of 20–30 km was distributed in the Okinawa Trough at depths of 0–20 km. In part of this area, magma intrusions and associated complex structures have been detected by a seismic reflection survey. The scale of the structures discussed in this study is almost the same with that discussed in the reflection survey. The rjMCMC-based analysis made it possible to compare random inhomogeneities with the structural variations estimated by the deterministic seismic reflection survey. Since analyses of scattered seismic waves can examine much greater depths than seismic reflection surveys, further comparisons between the two methods in the shallow crust could provide useful insights for detailed interpretation of complex structures at deeper depth.
Investigations into the relationship between domoic acid and copepods in Scottish waters
Authors: Cook Kathryn B , Lacaze Jean-Pierre , Machairopoulou Margarita , Bresnan Eileen
Published: December 2021

This study investigated impacts of the algal toxin domoic acid (DA) on copepods in Scottish waters. Inspection of seasonal patterns revealed that several common copepods (Acartia spp. Dana, 1846, Calanus spp. Leach, 1816, Centropages spp. Krøyer, 1849, Pseudocalanus spp. Boeck, 1872, and Temora longicornis (Müller O.F., 1785)) regularly coexist with potentially toxic species from the diatom genus Pseudo-nitzschia H. Peragallo in H. Peragallo and M Peragallo, 1900. A short field study investigating the DA content of Calanus spp. at the Scottish Coastal Observatory site at Stonehaven recorded DA during every sampling event. The highest DA levels were associated with a July bloom (∼135000 cells L−1) of Pseudo-nitzschia cf. plurisecta Orive & Pérez-Aicua 2013. Several studies have previously investigated effects of ingested DA on copepods but information on effects of dissolved DA is lacking, therefore, simple exposure experiments were carried out to measure mortality of copepod species at ecologically relevant concentrations of dissolved DA. The highest concentrations tested (≥ 50 ng DA mL−1) decreased survival in Temora longicornis only; survival of other copepod species was unaffected. However, T. longicornis feeding on non-toxic algae in the presence of dissolved DA did not accumulate DA in their tissue. This study provides evidence of the potential for Calanus spp. to act as vectors for DA to higher trophic levels in Scottish waters.
Shifts in neritic copepod communities off the Basque coast (southeastern Bay of Biscay) between 1998 and 2015
Authors: Iriarte Arantza , Villate Fernando , Uriarte Ibon , Bidegain Gorka , Barroeta Ziortza
Published: December 2021

The interannual variations in absolute and relative densities of copepods from the neritic waters of the southeastern Bay of Biscay and their relationship to climate teleconnections and local environmental factors were assessed using time series for the 1998–2015 period. Opposite patterns of variation of the absolute densities of spring Acartia clausi and Centropages typicusspecies vs. summer/autumn species, mainly Oncaea media, but also Ditrichocorycaeus anglicus, Oithona nana, Temora stylifera, and Oithona plumifera were detected. This type of opposite patterns were also observed between the relative densities of the spring A. clausi and summer Paracalanus parvus species. These opposite density patterns were positively correlated to all seasons North Atlantic Oscillation (NAO), spring East Atlantic pattern (EA), summer and autumn water temperature and summer chlorophyll a. They were negatively correlated to summer EA pattern, the winter and spring Atlantic Multidecadal Oscillation (AMO) and water temperature, and the upwelling index of all seasons. In these patterns of copepod variation two regime shifts were detected, one in 2008 towards an increase in the spring species and the other one in 2014–2015 towards an increase of summer species. This latter regime shift coincides in time with the abrupt community shifts predicted in the literature for 2014.
Pipecolic Acid, a Putative Mediator of the Encephalopathy of Cerebral Malaria and the Experimental Model of Cerebral Malaria
Authors: Keswani Tarun , Obeidallah Aisha , Nieves Edward , Sidoli Simone , Fazzari Melissa , Taylor Terrie , Seydel Karl , Daily Johanna P
Published: December 2021

Background

We explored a metabolic etiology of cerebral malaria (CM) coma.

Methods

Plasma metabolites were compared between Malawian children with CM and mild Plasmodium falciparum malaria. A candidate molecule was further studied in animal models of malaria.

Results

Clinically abnormal concentrations of pipecolic acid (PA) were present in CM plasma, and nearly normal in mild malaria samples. PA is renally cleared and the elevated PA blood levels were associated with renal insufficiency, which was present only in CM subjects. Prior studies demonstrate that PA has neuromodulatory effects and is generated by malaria parasites. PA brain levels in Plasmodium berghei ANKA–infected animals in the experimental cerebral malaria (ECM) model inversely correlated with normal behavior and correlated with blood-brain barrier (BBB) permeability. Mice infected with malaria species that do not induce neurological abnormalities or manifest BBB permeability had elevated plasma PA levels similar to ECM plasma at 7 days postinfection; however, they had low PA levels in the brain compared to ECM mice brains at 7 days postinfection.

Conclusions

Our model suggests that malaria-generated PA induces coma in CM and in ECM. The role of BBB permeability and the mechanisms of PA neuromodulation in CM will require additional investigation.
Unequal order T-spline meshes for fracture in poroelastic media
Authors: Hageman Tim , de Borst René
Published: December 2021

Spline-based meshes allow for a higher inter-element continuity. For coupled problems, e.g. poroelasticity, different meshes with different orders of interpolation are normally used for the various fields in order to avoid spurious oscillations. When including discontinuities in these meshes, there exist several options for the discretisation. Herein we will discuss two options which use T-splines, one aiming at a minimum number of degrees of freedom around the crack tip, the other trying to maximise this number. Both meshes retain a higher-order continuity along the fracture, but the mesh which maximises the number of degrees of freedom mesh introduces two additional degrees of freedom around the crack tip to allow for a sharper crack. The two discretisations are used to simulate a pressurised fracture inside a poroelastic material and the results are compared to results obtained using a Non-Uniform Rational B-Spline (NURBS) mesh. A comparison between the two discretisations shows the effect of including additional degrees of freedom close to the crack tip. However, both meshes yield similar results further away from the crack tip. It is shown that both T-spline meshes capture a fully closed discontinuity at the fracture tip, whereas the NURBS mesh retains a small opening due to the discontinuity which exists for the cracked as well as the intact elements. A fully closed fracture aperture results in T-splines with a lower discontinuity pressure compared to NURBS, making T-splines more suitable for simulations in which the fracture propagation is limited by the fluid transport within the fracture.
The weak dependence of velocity dispersion on disc fractions, mass-to-light ratio, and redshift: implications for galaxy and black hole evolution
Authors: Marsden Christopher , Shankar Francesco , Bernardi Mariangela , Sheth Ravi K , Fu Hao , Lapi Andrea
Published: December 2021

Velocity dispersion (σ) is a key driver for galaxy structure and evolution. We here present a comprehensive semi-empirical approach to compute σ via detailed Jeans modelling assuming both a constant and scale-dependent mass-to-light ratio M*/L. We compare with a large sample of local galaxies from MaNGA and find that both models can reproduce the Faber–Jackson (FJ) relation and the weak dependence of σ on bulge-to-total (B/T) ratio (for B/T ≳ 0.25). The dynamical-to-stellar mass ratio within R ≲ Re can be fully accounted for by a gradient in M*/L. We then build velocity dispersion evolutionary tracks σap[M*, z] (within an aperture) along the main progenitor dark matter haloes assigning stellar masses, effective radii, and Sérsic  indices via a variety of abundance matching and empirically motivated relations. We find: (1) clear evidence for downsizing in σap[M*, z] along the progenitor tracks; (2) at fixed stellar mass σ ∝ (1 + z)0.2−0.3 depending on the presence or not of a gradient in M*/L. We extract σap[M*, z] from the TNG50 hydrodynamic simulation and find very similar results to our models with constant M*/L. The increasing dark matter fraction within Re tends to flatten the σap[M*, z] along the progenitors at z ≳ 1 in constant M*/L models, while σap[M*, z] have a steeper evolution in the presence of a stellar gradient. We then show that a combination of mergers and gas accretion is likely responsible for the constant or increasing σap[M*, z] with time. Finally, our σap[M*, z] are consistent with a nearly constant and steep Mbh − σ relation at z ≲ 2, with black hole masses derived from the LX − M* relation.