bluuebunny/crossref_metadata_2025 huggingface dataset:
The Double Stitch Everting Technique in the End-to-Side Microvascular Anastomosis: Validation of the Technique Using a Randomized N-of-1 Trial
Authors: Dindelegan George C. , Dammers Ruben , Oradan Alex V. , Vinasi Ramona C. , Dindelegan Maximilian , Volovici Victor
Published: October 2020

Background The double stitch everting (DSE) technique, in which time is won by leaving the needle inside the vessel wall in-between stitching, is a modification of the end-to-side (ETS) anastomosis in the interest of reducing anastomosis time. This ensures proper wall eversion, intima-to-intima contact, and improved suture symmetry.

Methods We designed an N-of-1 randomized trial with each microsurgeon as their own control. We included 10 microsurgeons of different levels of experience who were then asked to perform classic and DSE ETS anastomoses on the chicken leg and rat femoral models. Every anastomosis was cut and evaluated using blinded assessment. Two-way analysis of variance (ANOVA) and multivariable logistic regression were used to analyze the results and for confounder adjustment.

Results A total of 210 anastomoses were performed, of which 177 on the chicken leg and 43 on the rat femoral artery and vein. From the 210 anastomoses, 111 were performed using the classic technique and 99 using the DSE technique. The mean anastomosis time was 28.8 ± 11.3 minutes in the classic group and 24.6 ± 12 minutes in the DSE group (p < 0.001, t-test). There was a significant reduction (p < 0.001, two-way ANOVA) in the number of mistakes when using the DSE technique (mean 5.5 ± 2.6) compared with those using the classic technique (mean 7.7 ± 3.4).

Conclusion The DSE technique for ETS anastomoses improves anastomoses times in experienced and moderately experienced microsurgeons while also improving or maintaining suture symmetry and lowering the number of mistakes.
Intraoperative Real-Time Visualization of the Lymphatic Vessels Using Microscope-Integrated Laser Tomography
Authors: Hayashi Akitatsu , Yoshimatsu Hidehiko , Visconti Giuseppe , Sujarittanakarn Sasithorn , Giacalone Guido , Hayashi Nobuko , Yamamoto Takumi , Yang Johnson Chia-Shen , Hong Joon Pio
Published: October 2020

Background Detection and selection of the lymphatic vessels are important for maximizing therapeutic efficacy of lymphaticovenular anastomosis (LVA). Some imaging modalities have been reported to be useful for intraoperative identification of the lymphatic vessels, but they have limitations. In this article, we present new capabilities of intraoperative laser tomography, which was used to evaluate the lumen of the lymphatic vessel and to validate the patency of anastomosis.

Methods Fifty-two patients with upper extremity lymphedema secondary to breast cancer treatment underwent indocyanine green (ICG) lymphography and real-time laser tomography imaging of ICG-enhanced lymphatic vessels intraoperatively before transecting the vessels during LVA. The imaging findings of the lymphatic vessels in laser tomography were investigated. Time required for scanning of the lymphatic vessels was compared between laser tomography and ultrasonography. The correlation between the thickness of the lymphatic vessel wall measured with laser tomographic imaging and the histologically measured thickness of the lymphatic vessel wall was examined. The patency of anastomosis sites was determined based on the image using laser tomography immediately after establishment of LVA.

Results A total of 132 ICG-enhanced lymphatic vessels were scanned with laser tomography showing clear lumen with surrounding vessel wall. The required time for lymphatic vessel scanning was significantly shorter with laser tomography than with ultrasonography (1.6 ± 0.3 vs. 4.8 ± 1.2 minutes; p = 0.016). Strong correlation was seen between the thickness of the lymphatic vessels wall measured using laser tomography and the histologically measured thickness of the lymphatic vessel wall (r = 0.977, 95% confidence interval: 0.897–0.992, p < 0.001). The quality of patency was evaluated immediately after anastomosis, which assisted in deciding whether reanastomosis was needed.

Conclusion Microscope-integrated laser tomography provides real-time images of the lymphatic vessels in extremely high resolution and enables evaluation of lymphatic lumen condition and objective post-LVA anastomosis status.
Magnetic steps on the threshold of the normal state
Authors: Assaad W.
Published: October 2020

Superconductivity in the presence of a step magnetic field has recently been the focus of many works. This contribution examines the behavior of a two-dimensional superconducting domain when superconductivity is lost in the whole domain except near the intersection points of the discontinuity edge and the boundary. The problem involves its own effective energy. We provide local estimates of the minimizers in the neighborhoods of the intersection points. Consequently, we introduce new critical fields marking the loss of superconductivity in the vicinity of these points. This study is modeled by the Ginzburg–Landau theory, and large Ginzburg–Landau parameters are considered.
High thermopower and power factors in EuFeO3 for high temperature thermoelectric applications: A first-principles approach
Authors: Iyyappa Rajan P. , Baldo Carlos , Enamullah  , Mahalakshmi S. , Navamathavan R. , Adinaveen T.
Published: October 2020

Thermoelectric materials that can work at operating temperatures of T ≥ 900 K are highly desirable since the key thermoelectric factors of most thermoelectric materials degrade at high temperatures. In this work, we investigate the high temperature thermoelectric performance of EuFeO3 using a combination of first-principles methods and semi-classical Boltzmann transport theory. High temperature thermoelectric performance is achieved owing to the presence of corrugated flatbands in the valence band region and extremely flatbands in the conduction band region. The lowest energetic structure of EuFeO3 lies within a G-type antiferromagnetic configuration, and the effect of compressive and tensile strains (−7% to +7%) along the (a, b) axes on thermoelectric performance is systematically analyzed. An extremely high value of the Seebeck coefficient (more than 1000 μV/K) is consistently recorded in the high temperature region between 900 K and 1400 K in this material. Furthermore, electrical conductivities and power factors are high and electronic thermal conductivities are low in the considered range of temperatures. The calculated theoretical minimum lattice conductivity is small, estimated at around 1.47–1.54 W m−1 K−1. A compressive strain of −3% is revealed to be the optimum level of strain for enhancing the key thermoelectric factors. Overall, p-type doping shows better thermoelectric performance than n-type doping in EuFeO3.
Generalized inverse matrix normalization algorithm to extract high-temperature data from multiwavelength pyrometry
Authors: Xing Jian , Liu Zhijun , Luo Jiashun , Han Bing
Published: October 2020

Multiwavelength pyrometry (MWP) is one of the most powerful tools for the precise measurement of high temperatures on the surfaces of non-gray materials. However, the unknown spectral emissivity of target materials is the most difficult obstacle to overcome in processing temperature inversion data using MWP. A direct and fast generalized inverse matrix normalization (GIM-NOR) data processing algorithm based on GIM theory for underdetermined equations is proposed in order to minimize the effects arising from unknown emissivity. The shape of the emissivity distribution is obtained so that the channel with the greatest emissivity can be selected in order to obtain a value close to the real temperature. The final inversion accuracy is then further improved using a NOR compensation method. Six kinds of materials with a distribution of emissivities at 1800 K were used to simulate and verify the proposed algorithm. The results show that the average relative error of temperature inversion was 0.63%, obtained within 8 ms computation time using a standard desktop computer, and the accuracy and efficiency were largely unaffected when 5% random noise was inserted into the simulation data. A set of experimental data for rocket nozzle temperature measurements with MWP were also processed based on the proposed novel algorithm. The results show that the relative error on the temperature was less than 0.50%, for a design temperature of 2490 K, and that the processing efficiency was very high, that is, within 9 ms. Simulation and experiment both proved that the proposed efficient data processing algorithm for MWP based on GIM theory was unaffected by emissivity and achieved good inversion precision and fast data processing. Therefore, the proposed new data processing algorithm for MWP data for measuring transient high temperatures has very broad potential applications, and it also provides a theoretical basis for measuring high-temperature fields using MWP.
A minimum quantum chemistry CCSD(T)/CBS dataset of dimeric interaction energies for small organic functional groups
Authors: Chang Yu-Ming , Wang Yi-Siang , Chao Sheng D.
Published: October 2020

We have performed a quantum chemistry study on the bonding patterns and interaction energies for 31 dimers of small organic functional groups (dubbed the SOFG-31 dataset), including the alkane–alkene–alkyne (6 + 4 + 4 = 14, AAA) groups, alcohol–aldehyde–ketone (4 + 4 + 3 = 11, AAK) groups, and carboxylic acid-amide (3 + 3 = 6, CAA) groups. The basis set superposition error corrected super-molecule approach using the second order Møller–Plesset perturbation theory (MP2) with the Dunning’s aug-cc-pVXZ (X = D, T, Q) basis sets has been employed in the geometry optimization and energy calculations. To calibrate the MP2 calculated interaction energies for these dimeric complexes, we perform single-point calculations with the coupled cluster with single, double, and perturbative triple excitations method at the complete basis set limit [CCSD(T)/CBS] using the well-tested extrapolation methods. In order to gain more physical insights, we also perform a parallel series of energy decomposition calculations based on the symmetry adapted perturbation theory (SAPT). The collection of these CCSD(T)/CBS interaction energy values can serve as a minimum quantum chemistry dataset for testing or training less accurate but more efficient calculation methods. As an application, we further propose a segmental SAPT model based on chemically recognizable segments in a specific functional group. These model interactions can be used to construct coarse-grained force fields for larger molecular systems.
Confinement of an alkaline-earth element in a grating magneto-optical trap
Authors: Sitaram A. , Elgee P. K. , Campbell G. K. , Klimov N. N. , Eckel S. , Barker D. S.
Published: October 2020

We demonstrate a compact magneto-optical trap (MOT) of alkaline-earth atoms using a nanofabricated diffraction grating chip. A single input laser beam, resonant with the broad 1S0 → 1P1 transition of strontium, forms the MOT in combination with three diffracted beams from the grating chip and a magnetic field produced by permanent magnets. A differential pumping tube limits the effect of the heated, effusive source on the background pressure in the trapping region. The system has a total volume of around 2.4 l. With our setup, we have trapped up to 5 × 106 88Sr atoms at a temperature of ∼6 mK, and with a trap lifetime of ∼1 s. Our results will aid the effort to miniaturize quantum technologies based on alkaline-earth atoms.
A density-functional theory study of the Al/AlOx/Al tunnel junction
Authors: Kim Chang-Eun , Ray Keith G. , Lordi Vincenzo
Published: October 2020

The aluminum oxide tunnel junction is a key component of the majority of superconducting quantum devices. For high-quality, reproducible, and scalably manufacturable qubits, the ability to fabricate Josephson junctions (JJs) with a targeted critical current and high uniformity is essential. We use first-principles modeling to assess fundamental aspects of the atomic structure of both amorphous and crystalline aluminum oxide tunnel junctions and relate the structure to predicted performance metrics. We use modified ab initio molecular dynamics to develop realistic models of the tunnel junction, from which interface roughness and local thickness fluctuations are analyzed in an unbiased manner by training a neural network to identify the boundary between metal and oxide. We show that the effective thickness of the insulating part of the junction can be different from the apparent physical thickness. We calculate the rate of Cooper pair tunneling for the atomically resolved electrostatic potential using direct numerical solution in 3D, which shows a channeling effect that impacts the junction critical current. The predicted critical current is a useful JJ design parameter that can be accessed from the ab initio calculations without fitting parameters. To assess the limits of uniformity and fabrication choices (e.g., oxidation vs epitaxy), we compare the amorphous junctions to crystalline models, which show order of magnitude more efficient tunneling compared to the amorphous case, underlining the connection between atomistic structure and Cooper pair tunneling efficiency. Further, this work provides a foundation for ab initio materials design and evaluation to help accelerate future development of improved tunnel junctions.
Velocity bunching dynamics of attosecond electron beam in a DC-gun based high repetition-rate beamline
Authors: Zhou Zheng , Li Peng , Wu Dai , Li Ming
Published: October 2020

We investigate the possibility of generating attosecond electron beams with sub-fC charges and a beam energy of a few MeV from a DC-gun and two super-conducting linac based high repetition-rate photoinjector, a promising candidate for next-generation high-flux ultrafast electron diffraction (UED). Using two super-conducting linac photoinjectors, a cascade velocity bunching scheme is adopted to compress the picosecond long e-beam generated by the DC-gun. Thorough dynamic simulations showed that an electron bunch with 2×103 electrons could be compressed to a few hundreds of attoseconds. In such an ultra-low charge domain, space charge induced slice energy spread is identified to be the main obstacle for further compression, and the final bunch length will become shorter with the reduction of the bunch charge in the power function. Combining merits of the ultra-short bunch duration and the high repetition-rate, such extraordinary electron beams should have great potential to further improve the temporal resolving power of UED facilities.
Temperature dependent charge transport of acid-treated poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) thin films
Authors: Sharma Meenu , Maity K. P. , Rani Sonam , Prasad V. , Sameera I. , Bhatia Ravi
Published: October 2020

Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is an important opto-electronic material, and its room temperature electrical conductivity can be prominently enhanced by chemical treatment; it is technologically significant to investigate its temperature and magnetic field dependent charge transport characteristics. Here, we analyzed the low temperature charge transport properties of pristine and acid-treated PEDOT:PSS thin films by studying the variation in resistance as a function of temperature and magnetic field (T ∼ 300 to 4.2 K, H ∼ up to 5 T). The acid-treated sample exhibited much improved charge transport behavior at low T, with a resistivity ratio [ρ(4.2 K)/ρ(300 K)] of ∼5.7 × 102, which is three orders of magnitude smaller than that of the pristine sample. Nevertheless, both pristine and acid-treated samples followed hopping conduction, obeying R(T)∝expT−1/2andR(T)∝expT−1/3, respectively, in the low T regime. Furthermore, positive magnetoresistance of ∼16% (at 4.2 K and 5 T) was displayed by acid-treated samples that could be due to the wave function shrinkage phenomenon.
Role of local order in anomalous ion diffusion: Interrogation through tetrahedral entropy of aqueous solvation shells
Authors: Banerjee Puja , Bagchi Biman
Published: October 2020

Small rigid ions perturb the water structure around them significantly. At constant viscosity, alkali cations (Li+, Na+, and so on) exhibit an anomalous non-monotonic dependence of diffusivity on ion-size, in stark violation of the Stokes–Einstein expression. Although this is a well-known problem, we find that an entropic view of the problem can be developed, which provides valuable insight. The local entropy experienced by the solute ion is relevant here, which leads to the connection with local viscosity, discussed earlier by many. Due to the strong interactions with ions, the translational and rotational entropy of solvation water decreases sharply; however, an opposite effect comes from the disruption of the tetrahedral network structure of water near the charges. We compute the tetrahedral order of water molecules (qtet) around the ion and suitably defined tetrahedral entropy [S(qtet)] that is a contribution to the excess entropy of the system. Our results reveal that although the structural properties of the second shell become nearly identical to the bulk, S(qtet) of the second shell is found to play an important role in giving rise to the non-monotonic ion-size dependence. The detailed study of the static and dynamic fluctuations in qtet and the number of hydration water molecules provides interesting insights into correlation between the structure and dynamics; the smallest static fluctuation of qtet for the first hydration shell water molecules of Li+ is indicative of the iceberg picture. The study of fluctuation properties of qtet and the coordination number also reveals the role of the second hydration layer and could explain the anomalous behavior of the Rb+ ion.
Energy barriers and cooperative motion at the surface of freestanding glassy polystyrene films
Authors: Fujimoto D. , MacFarlane W. A. , Rottler J.
Published: October 2020

We investigate the near-surface relaxation of freestanding atactic polystyrene films with molecular dynamics simulations. As in previous coarse-grained simulations, relaxation times for backbone segments and phenyl rings are linked to their bulk relaxation times via a power-law coupling relation. Variation of the coupling exponent with distance from the surface is consistent with depth-dependent activation barriers. We also quantify a reduction in dynamical heterogeneity at the interface, which can be interpreted in the framework of cooperative models for glassy dynamics.
Recent advances in understanding propeller jet flow and its impact on scour
Authors: Wei Maoxing , Chiew Yee-Meng , Cheng Nian-Sheng
Published: October 2020

This paper presents an extensive review of the characteristics of a propeller jet-induced flow field and its impact on scour formation. As the driving force of scour, the jet flow behavior is first explored, including both the free and bounded jets under various boundary conditions. Accordingly, their resulting scour, namely, unconfined and confined scour, are expounded in terms of the temporal and spatial development of the scour depth. Hitherto, existing methods for predicting the scour depth are principally developed empirically, which exclude in-depth scrutiny into the mechanism governing the scouring process. With the detailed flow fields obtained in recent research, this paper aims to piece together a state-of-the-art understanding of the scouring mechanism governing confined propeller scour, that is, the combined effect of jet flow and junction flow on the scour hole development. By comparing the similarities and differences between the scouring mechanisms in open and closed quays, this paper provides a comprehensive insight into the scouring process associated with bounded propeller jets. Moreover, in terms of the near-bed flow variations during the scouring process, implications for sediment transport under highly turbulent flow are discussed. Finally, future research needs are identified.
Non-adiabatic effects of nuclear motion in quantum transport of electrons: A self-consistent Keldysh–Langevin study
Authors: Kershaw Vincent F. , Kosov Daniel S.
Published: October 2020

The molecular junction geometry is modeled in terms of nuclear degrees of freedom that are embedded in a stochastic quantum environment of non-equilibrium electrons. The time-evolution of the molecular geometry is governed via a mean force, a frictional force, and a stochastic force, forces arising from many electrons tunneling across the junction for a given nuclear vibration. Conversely, the current-driven nuclear dynamics feed back to the electronic current, which can be captured according to the extended expressions for the current that have explicit dependences on classical nuclear velocities and accelerations. Current-induced nuclear forces and the non-adiabatic electric current are computed using non-equilibrium Green’s functions via a timescale separation solution of Keldysh–Kadanoff–Baym equations in the Wigner space. Applying the theory to molecular junctions demonstrated that non-adiabatic corrections play an important role when nuclear motion is considered non-equilibrium and, in particular, showed that non-equilibrium and equilibrium descriptions of nuclear motion produce significantly different current characteristics. It is observed that non-equilibrium descriptions generally produce heightened conductance profiles relative to the equilibrium descriptions and provide evidence that the effective temperature is an effective measure of the steady-state characteristics. Finally, we observe that the non-equilibrium descriptions of nuclear motion can give rise to the Landauer blowtorch effect via the emergence of multi-minima potential energy surfaces in conjunction with non-uniform temperature profiles. The Landauer blowtorch effect and its impact on the current characteristics, waiting times, and the Fano factor are explored for an effective adiabatic potential that morphs between a single, double, and triple potential as a function of voltage.
Computation of solid–fluid interfacial free energy in molecular systems using thermodynamic integration
Authors: Addula Ravi Kumar Reddy , Punnathanam Sudeep N.
Published: October 2020

In this article, we present two methods based on thermodynamic integration for computing solid–fluid interfacial free energy for a molecular system. As a representative system, we choose two crystal polymorphs of orcinol (5-methylbenzene-1,3-diol) as the solid phase and chloroform and nitromethane as the liquid phase. The computed values of the interfacial free energy are then used in combination with the classical nucleation theory to predict solvent induced polymorph selectivity during crystallization of orcinol from solution.
Increasing early life growth of hatchery-reared freshwater fish can improve stocking outcomes
Authors: Barrow Joshua S. , Yen Jian D. L. , Koehn John D. , Morrongiello John R.
Published: October 2020

Stock enhancement is an important tool used to rebuild depleted fish populations or enhance recreational fishing. Hatchery-reared individuals can express trait differences, such as growth, which may affect later survival. However, there is little understanding of how early life growth variation affects stocking success. We examined early life growth of golden perch Macquaria ambigua and assessed how growth within hatcheries affects the survival of stocked fish. We measured daily otolith increment widths at 10, 20 and 30 days after hatching, but before stocking into lakes in south-eastern Australia. Mean growth decreased with age, but variation in growth increased. We then compared the early life growth of these individuals to those recaptured after 2 years at liberty (age-2+). Faster individual growth between 20 and 30 days was positively correlated with increased length at stocking. Mean growth between 20 and 30 days of age-2+ fish was higher than that of young-of-year fish, but among-individual variation in growth did not differ between the two groups. These results suggest that individuals with fast hatchery growth have increased survival to 2 years. We propose that enhancing growth within hatcheries may increase the survival of stocked fish, and thus the cost-effectiveness of fish stocking.
Soil moisture as an indicator of growing-season herbaceous fuel moisture and curing rate in grasslands
Authors: Sharma Sonisa , Carlson J. D. , Krueger Erik S. , Engle David M. , Twidwell Dirac , Fuhlendorf Samuel D. , Patrignani Andres , Feng Lei , Ochsner Tyson E.
Published: October 2020

Soil moisture depletion during the growing season can induce plant water stress, thereby driving declines in grassland fuel moisture and accelerating curing. These drying and curing dynamics and their dependencies on soil moisture are inadequately represented in fire danger models. To elucidate these relationships, grassland fuelbed characteristics and soil moisture were monitored in nine patches of tallgrass prairie under patch-burn management in Oklahoma, USA, during two growing seasons. This study period included a severe drought (in 2012), which resulted in a large wildfire outbreak near the study site. Fuel moisture of the mixed live and dead herbaceous fuels (MFM) clearly tracked soil moisture, expressed as fraction of available water capacity (FAW). MFM decreased with decreasing soil moisture below an FAW threshold of 0.59 and fell below 30% only when FAW fell below 0.30. Likewise, the curing rate increased linearly as FAW declined below 0.30, while Normalized Difference Vegetation Index (NDVI) readings failed to adequately respond to rapid drying and curing of the fuelbed. Incorporating soil moisture observations into grassland fuelbed models could result in more accurate fuel moisture and curing estimates, contributing to improved wildfire danger assessments and reduced losses of life and property due to wildfire outbreaks.
Design principles for self-forming interfaces enabling stable lithium-metal anodes
Authors: Zhu Yingying , Pande Vikram , Li Linsen , Wen Bohua , Pan Menghsuan Sam , Wang David , Ma Zi-Feng , Viswanathan Venkatasubramanian , Chiang Yet-Ming
Published: October 2020

Significance

It is possible to nearly double the energy density of existing lithium-ion batteries by using lithium metal anodes. However, it has been known for decades that the lithium dendrites and mossy lithium formed during charging (electrodeposition) limit the cycle life of the batteries. It is important to change the growth behavior of lithium metal, which is closely related to the properties of the solid–electrolyte interface (SEI) formed via spontaneous reactions between the lithium metal and the electrolyte. In this experimental-modeling integrated study, we reveal the design principles of the SEI that facilitates the dendrite-free and dense deposition of lithium and demonstrate one of the best cycling performances of lithium metal anode to date under practically relevant conditions.
Horizontal gene transfer potentiates adaptation by reducing selective constraints on the spread of genetic variation
Authors: Woods Laura C. , Gorrell Rebecca J. , Taylor Frank , Connallon Tim , Kwok Terry , McDonald Michael J.
Published: October 2020

Significance

Bacteria can obtain genes from other bacteria, or the surrounding environment, by horizontal gene transfer (HGT). While it is clear that HGT is very important for microbial populations, it is not understood how HGT changes the rate or mechanisms of adaptation. In this study, we evolve populations of the bacteria
Helicobacter pylori
and use DNA sequencing to track the movement of HGT genes as they spread through the population. We show that HGT can help antibiotic resistance genes establish at a low frequency in a population, even in the absence of the antibiotic. We find that these HGT treatment populations flourish when treated with antibiotics, showing how HGT can potentiate adaptation to future environmental change.
The
Chlamydia
effector CT622/TaiP targets a nonautophagy related function of ATG16L1
Authors: Hamaoui Daniel , Cossé Mathilde M. , Mohan Jagan , Lystad Alf Håkon , Wollert Thomas , Subtil Agathe
Published: October 2020

Significance

Some intracellular bacteria develop inside a vacuole, which expands during the infection process. We show, here, that the protein ATG16L1 restricts the expansion of the
Chlamydia trachomatis
vacuole. ATG16L1 is well known for its role in autophagy, a process that contributes to the elimination of intracellular microbes. However, the restriction exerted by ATG16L1 on vacuole expansion relies on a different ATG16L1 function. We demonstrate that the bacteria secrete an effector protein that prevents ATG16L1 binding to TMEM59 and allows rerouting of vesicular traffic to the vacuole. The discovery that one bacterial effector evolved to target ATG16L1’s engagement in intracellular traffic emphasizes the importance this secondary activity of ATG16L1 for maintaining host cell homeostasis.
Interspecific competition slows range expansion and shapes range boundaries
Authors: Legault Geoffrey , Bitters Matthew E. , Hastings Alan , Melbourne Brett A.
Published: October 2020

Significance

Range expansion is how invasive species spread and how species track habitats shifting from climate change, so understanding this process is a key applied and basic challenge. Ecologists have long theorized that a competitor can slow or even halt range expansion. However, there has never been definitive empirical evidence of interspecific competition affecting expansion dynamics, and forecasts of spread generally do not consider competitive interactions. We demonstrate experimentally that competition between species can slow range expansion across multiple generations. We also show that competition and density-dependent dispersal continuously alter the shape of the expanding range boundary such that the shape changes over time. Therefore, accurate forecasts of range expansion must account for interactions between competing species.
Mobile device data reveal the dynamics in a positive relationship between human mobility and COVID-19 infections
Authors: Xiong Chenfeng , Hu Songhua , Yang Mofeng , Luo Weiyu , Zhang Lei
Published: October 2020

Accurately estimating human mobility and gauging its relationship with virus transmission is critical for the control of COVID-19 spreading. Using mobile device location data of over 100 million monthly active samples, we compute origin–destination travel demand and aggregate mobility inflow at each US county from March 1 to June 9, 2020. Then, we quantify the change of mobility inflow across the nation and statistically model the time-varying relationship between inflow and the infections. We find that external travel to other counties decreased by 35% soon after the nation entered the emergency situation, but recovered rapidly during the partial reopening phase. Moreover, our simultaneous equations analysis highlights the dynamics in a positive relationship between mobility inflow and the number of infections during the COVID-19 onset. This relationship is found to be increasingly stronger in partially reopened regions. Our study provides a quick reference and timely data availability for researchers and decision makers to understand the national mobility trends before and during the pandemic. The modeling results can be used to predict mobility and transmissions risks and integrated with epidemics models to further assess the public health outcomes.
Model-free decision making is prioritized when learning to avoid harming others
Authors: Lockwood Patricia L. , Klein-Flügge Miriam C. , Abdurahman Ayat , Crockett Molly J.
Published: October 2020

Significance

“Do no harm” is a universal principle of human social life. But how do we learn which of our actions help or harm others? Learning theory suggests there are two different systems that govern how we link actions and outcomes: a model-free system that is efficient and a model-based system that is deliberative. Here we show that people rely more on model-free decision making when learning to avoid harming others compared to themselves. Model-free neural signals that distinguish self and other are observed in the thalamus/caudate, and reliance on model-free moral learning for others varies with individual differences in moral judgment. These findings suggest that moral decision making for others is more model-free and has a specific neural signature.
Toxin-like neuropeptides in the sea anemone
Nematostella
unravel recruitment from the nervous system to venom
Authors: Sachkova Maria Y. , Landau Morani , Surm Joachim M. , Macrander Jason , Singer Shir A. , Reitzel Adam M. , Moran Yehu
Published: October 2020

Significance

Although venom has evolved independently numerous times in animals, the origin of many proteins composing venom remains poorly characterized. We report a case of protein recruitment from the nervous to venom system in the sea anemone
Nematostella
. We discovered a toxin packaged in the stinging cells and with lethal activity against fish. Surprisingly, it is similar to a peptide from the nervous system (neuropeptide) regulating
Nematostella
development. Comparisons with other sea anemones showed that these two functionally different peptides originated due to a duplication of a neuropeptide gene followed by recruitment of one of the copies into venom. Additionally, we characterized four other toxin-like neuropeptides, suggesting a recurring pattern of venom recruitment from neuropeptides in sea anemones.
TLR4 signaling and macrophage inflammatory responses are dampened by GIV/Girdin
Authors: Swanson Lee , Katkar Gajanan D. , Tam Julian , Pranadinata Rama F. , Chareddy Yogitha , Coates Jane , Anandachar Mahitha Shree , Castillo Vanessa , Olson Joshua , Nizet Victor , Kufareva Irina , Das Soumita , Ghosh Pradipta
Published: October 2020

Significance

To ensure immunity, and yet limit pathology, inflammatory responses must be confined within the proverbial “Goldilocks zone.” TLR4 is the prototypical sensor that orchestrates inflammatory responses through a series of well-characterized downstream cascades. How TLR4 signals are confined remains incompletely understood. Using trans-scale approaches ranging from disease modeling in live animals, through cell-based interventional studies, to structure-guided biochemical studies that offer an atomic-level resolution, this study unravels the existence of a “brake” within the TLR4-signaling cascade, i.e., GIV; the latter is a prototypical member of an emerging class of scaffold proteins. By showing that GIV uses conserved mechanisms to impact multi-TLR signaling, this work unravels a multiscale point of convergence of immune signaling of broader impact beyond TLR4.
Stimulator of interferon genes (STING) is an essential proviral host factor for human rhinovirus species A and C
Authors: McKnight Kevin L. , Swanson Karen V. , Austgen Kathryn , Richards Cindy , Mitchell Jonathan K. , McGivern David R. , Fritch Ethan , Johnson John , Remlinger Katja , Magid-Slav Michal , Kapustina Maryna , You Shihyun , Lemon Stanley M.
Published: October 2020

Significance

We show here that efficient replication of RV-A and RV-C viruses, common respiratory pathogens with positive-strand RNA genomes, requires STING, a host protein with canonical function in innate immune responses to DNA viruses. STING is enriched in PI4P-containing membranes of RV-A replication organelles and is essential for a step in replication of the viral RNA genome. Its host factor activity is highly species-specific, and adaptation of the RV-16 virus to murine STING promotes RV-16 replication in cells of murine origin. These findings add substantially to the current understanding of essential host factors that restrict the host species range of RVs and limit the development of small animal models.
The language of exclusion
Authors: Talay Louis
Published: October 2020

It has been argued that far-right populist parties (FRPP) distinguish themselves from other parties on the right of the political spectrum through their strong association with nationalism, anti-elitism, authoritarianism and historical mythologizing. These features typically manifest in discourse that attempts to justify exclusionist immigration and asylum policies by presenting Islam as an existential threat to predominantly white societies. This paper seeks to establish whether a conservative party that has never been considered populist could possess the same features as an FRPP by comparing three selected discursive texts – one from mainstream conservative party leader John Howard and two from prominent European FRPP leaders. The analysis revealed that the key difference between the three leaders was Howard’s failure to satisfy the authoritarianism criterion, which was interpreted as a decisive factor in his party’s moderate guise. This suggests that some mainstream parties may be more ideologically extremist than they are perceived to be.
Animals vs. armies
Authors: Hart Christopher
Published: October 2020

Within the emerging paradigm of experimental Critical Discourse Analysis, this paper investigates the framing effects of dehumanising vs militarising metaphors in anti-immigration discourses. These metaphors are characterised as ‘extreme metaphors’ in so far as they are manifestly metaphorical and obviously inflammatory. Attested examples of these metaphors in political and media discourses are identified and critically analysed before their potential framing effects are investigated experimentally.

Contrary to predictions, alternative metaphors did not increase support for actions and evaluations consistent with the unique framings that they present. In fact, extreme metaphors decreased support for anti-immigration sentiments and hostile immigration policies compared to literal framings. It seems that extreme metaphors alert readers to the metaphorical framing being presented so that, among certain groups of people, the framing is more readily scrutinised and rejected, prompting readers adopt more sympathetic attitudes toward immigration. The implications of these findings for Critical Discourse Analysis are discussed.
Structural Domain Imaging and Direct Determination of Crystallographic Orientation in Noncentrosymmetric Ca3Ru2O7 Using Polarized Light Reflectance*
Authors: Tang Guoxiong , Wen Libin , Xing Hui , Liu Wenjie , Peng Jin , Wang Yu , Li Yupeng , Lv Baijiang , Yang Yusen , Yao Chao , Wu Yueshen , Sun Hong , Xu Zhu-An , Mao Zhiqiang , Liu Ying
Published: October 2020

The noncentrosymmetricity of a prototypical correlated electron system Ca3Ru2O7 renders extensive interest in the possible polar metallic state, along with multiple other closely competing interactions. However, the structural domain formation in this material often complicates the study of intrinsic material properties. It is crucial to fully characterize the structural domains for unrevealing underlying physics. Here, we report the domain imaging on Ca3Ru2O7 crystal using the reflection of polarized light at normal incidence. The reflection anisotropy measurement utilizes the relative orientation between electric field component of the incident polarized light and the principal axis of the crystal, and gives rise to a peculiar contrast. The domain walls are found to be the interfaces between 90° rotated twin crystals by complementary magnetization measurements. A distinct contrast in reflectance is also found in the opposite cleavage surfaces, owing to the polar mode of the RuO6 octahedra. More importantly, the analysis of the contrast between all inequivalent cleavage surfaces enables a direct determination of the crystallographic orientation of each domain. Such an approach provides an efficient yet feasible method for structural domain characterization, which can also find applications in noncentrosymmetric crystals in general.
Perovskite Termination-Dependent Charge Transport Behaviors of the CsPbI3/Black Phosphorus van der Waals Heterostructure*
Authors: Cao Yong-Hua , Bai Jin-Tao , Feng Hong-Jian
Published: October 2020

Fundamental understanding of interfacial charge behaviors is of great significance for the optoelectronic and photovoltaic applications. However, the crucial roles of perovskite terminations in charge transport processes have not been completely clear. We investigate the charge transfer behaviors of the CsPbI3/black phosphorus (BP) van der Waals heterostructure by using the density functional theory calculations with a self-energy correction. The calculations at the atomic level demonstrate the type-II band alignments of the CsPbI3/BP heterostructure, which make electrons transfer from the perovskite side to monolayer BP. Moreover, the stronger interaction and narrower physical separation of the interfaces can lead to higher charge tunneling probabilities in the CsPbI3/BP heterostructure. Due to different electron affinities, the PbI2-terminated perovskite slab tends to collect electrons from the adjacent materials, whereas the CsI-termination prefers to inject electrons into transport materials. In addition, the interface coupling effect enhances the visible-light-region absorption of the CsPbI3/BP heterostructure. This study highlights the importance of the perovskite termination in the charge transport processes and provides theoretical guidelines to develop high-performance photovoltaic and optoelectronic devices.
Acceleration of charged particles from near-extremal rotating black holes embedded in magnetic fields
Authors: Coimbra-Araújo C H , Anjos R C
Published: October 2020

The aim of the present article is to evaluate the motion of neutral and charged test particles in the vicinity of a near-extremal rotating black hole (BH) in the presence of magnetic fields. Euler–Lagrange motion equations and effective potential methods are used to characterize the motion out of the equatorial plane. Such approach is of peculiar significance if it is considered, e.g., accretion processes onto rotating BHs. In general, investigations concerning accretion focus mostly on the simplest case of particles moving in the equatorial plane. Here it will be considered that particles initially moving around some particular orbit may be perturbed by a kick along the θ direction, giving rise to other possible orbits. We confirm the possibility that ultra high energy cosmic rays would be produced at the very center of AGNs, for a specific range of magnetic field magnitudes, since it is possible that ultra-high center-of-mass energies can be produced by particles colliding near the horizon of rotating BHs whose angular momentum tends to the Thorne limit.
High intensity x-ray interaction with a model bio-molecule system: double-core-hole states and fragmentation of formamide
Authors: Koulentianos D , Fouda A E A , Southworth S H , Bozek J D , Küpper J , Santra R , Kryzhevoi N V , Cederbaum L S , Bostedt C , Messerschmidt M , Berrah N , Fang L , Murphy B , Osipov T , Cryan J P , Glownia J , Ghimire S , Ho P J , Krässig B , Ray D , Li Y , Kanter E P , Young L , Doumy G
Published: October 2020

Formamide, a simple model bio-molecule (HCONH2), is irradiated with high intensity, ultrashort pulses from an x-ray free electron laser. Ionic fragments resulting from photoionization and subsequent decay processes are recorded, as well as the electronic signature of the different inner shell ionization events that can take place during the x-ray pulses. The formation of double-core-hole states, where a second inner shell electron is removed before the first core hole has been refilled is observed in the electron spectra, recorded at all three sites (C, N, O) of the molecule. The individual ionization potentials are compared with results of ab initio calculations at different level of theory. Based on our results, future opportunities for advanced studies of inner-shell-induced electronic and nuclear dynamics are explored.
Current-induced nonreciprocity and refraction-suppressed propagation in a multilayered graphene-dielectric crystal
Authors: Huang D P , Xu K Y
Published: October 2020

Nonreciprocal photonic devices play a significant role in regulating the propagation of electromagnetic waves. Here we theoretically investigate the nonreciprocal properties of transverse magnetic modes in a multilayered graphene-dielectric crystal under an applied DC bias. We find that drifting electrons driven by the external DC electric field can give rise to extremely asymmetric dispersion diagrams. Furthermore, when the drifting electrons travel antiparallel to the normal component of the incident wave vector, negative refraction can be strongly suppressed, causing the energy of light to flow along the direction of the electric current. Our theoretical findings can be used to design nonreciprocal optoelectronic devices and enable light to propagate without refraction.
Utilization of group 10 2D TMDs-PdSe2 as a nonlinear optical material for obtaining switchable laser pulse generation modes
Authors: Cheng Ping Kwong , Tang Chun Yin , Ahmed Safayet , Qiao Junpeng , Zeng Long-Hui , Tsang Yuen Hong
Published: October 2020

In-plane anisotropic two-dimensional (2D) materials have gained considerable interest in the field of research, due to having the potential of being used in different device applications. Recently, among these 2D materials, group 10 transition metal dichalcogenides (TMDs) pentagonal Palladium diselenide (PdSe2) is utilized in various sections of researches like nanoelectronics, thermoelectric, spintronics, optoelectronics, and ultrafast photonics, owing to its high air stability and broad absorption spectrum properties. In this paper, it is demonstrated that by utilizing this novel 2D layered PdSe2 material as a saturable absorber (SA) in an EDF laser system, it is possible to obtain switchable laser pulse generation modes. At first, the Q-switching operation mode is attained at a threshold pump power of 56.8 mW at 1564 nm, where the modulation range of pulse duration and repetition rate is 18.5 μs–2.0 μs and 16.4 kHz–57.0 kHz, respectively. Afterward, the laser pulse generation mode is switched to the mode-locked state at a pump power of 63.1 mW (threshold value) by changing the polarization condition inside the laser cavity, and this phenomenon persists until the maximum pump power of 230.4 mW. For this mode-locking operation, the achieved pulse duration is 766 fs, corresponding to the central wavelength and 3 dB bandwidth of 1566 nm and 4.16 nm, respectively. Finally, it is illustrated that PdSe2 exhibits a modulation depth of 7.01%, which substantiates the high nonlinearity of the material. To the best of the authors’ knowledge, this is the first time of switchable modes for laser pulse generation are achieved by using this PdSe2 SA. Therefore, this work will encourage the research community to carry out further studies with this PdSe2 material in the future.
Internal friction behavior of Zr59Fe18Al10Ni10Nb3 metallic glass under different aging temperatures
Authors: Faisal Ghazi Israa , Meften Hashim Israa , Surendar Aravindhan , Salikhovich Tuguz Nalbiy , Aljeboree Aseel M. , Alkaim Ayad F. , Geetha Nisith
Published: October 2020

We investigate the role of aging temperature on relaxation of internal friction in Zr59Fe18Al10Ni10Nb3 metallic glass. For this purpose, dynamic mechanical analysis with different annealing temperatures and frequency values is applied. The results indicate that the aging process leads to decrease in the dissipated energy in the temperature range of glass transition. It is also found that the increase in applied frequency weakens the loss factor intensity in the metallic glass. Moreover, the Kohlrausch–Williams–Watts (KWW) equation is used to evaluate the evolution of internal friction during the aging process. According to the results, higher annealing temperature will make the primary internal friction in the material increase; however, a sharp decline is observed with the time. The drop in characteristic time of internal friction is also closely correlated to the rate of atomic rearrangement under the dynamic excitation so that at higher annealing temperatures, the driving force for the collaborative movement of atoms is easily provided and the mean relaxation time significantly decreases.