bluuebunny/crossref_metadata_2025 huggingface dataset:
Measurements of the imploding plasma sheath in triple-nozzle gas-puff z pinches
Authors: Lavine E. S. , Rocco S. V. R. , Potter W. M. , Angel J. , Freeman E. , Banasek J. T. , Lawson J. , Greenly J. B. , Wilhelm H. , Hammer D. A. , Kusse B. R.
Published: June 2022

Gas-puff z-pinch implosions are characterized by the formation of a dense annular plasma shell, the sheath, that is driven to the axis by magnetic forces and therefore subject to the magneto-Rayleigh–Taylor instability. Here, the conditions within these sheaths are measured on the 1-MA COBRA generator at Cornell University [Greenly et al., Rev. Sci. Instrum. 79, 073501 (2008)] for various gas species and initial fill densities. The gas-puff loads are initialized by a 7 cm diameter triple-nozzle gas valve assembly with concentric outer and inner annular nozzles and a central gas jet. Thomson scattering and laser interferometry provide spatially resolved flow, temperature, and electron density profiles midway through the implosion, while extreme ultraviolet pinhole cameras record the evolution of the plasma column and photoconducting diodes measure x-ray emission. Analysis of the scattering spectra includes a means of discriminating between thermal and non-thermal broadening to test for the presence of hydrodynamic turbulence. Two types of sheath profiles are observed, those with sharp discontinuities at the leading edge and those with smooth gradients. In both cases, non-thermal broadening is generally peaked at the front of the sheath and exhibits a characteristic decay length that roughly scales with the sheath ion mean free path. We demonstrate that this non-thermal broadening term is inconsistent with laminar velocity gradients and is more consistent with dissipative turbulence driven by unstable plasma waves in a collisionless shock. The resulting differences in sheath profile are then set by the sheath ion collisionality in a manner consistent with recent 1D kinetic simulations [Angus et al., Phys. Plasmas 28, 010701 (2021)].
Adaptive backstepping sliding mode control of permanent magnet spherical motor based on disturbance observer
Authors: Lu Zongchen , Li Guoli , Wang Qunjing , Zhou Sili , Gao Shihao
Published: June 2022

This paper proposes an adaptive backstepping sliding mode control method based on a nonlinear disturbance observer (NDO) to solve the problem that the tracking performance of the motion system of a permanent magnet spherical motor (PMSpM) is degraded due to the influence of external nonlinear disturbance. First, the dynamic model of the PMSpM under the compound interference is established. Second, an NDO and an adaptive backstepping sliding mode controller are designed to compensate for the external disturbances and modeling uncertainties, and the stability of the closed-loop system using the proposed method is confirmed through the Lyapunov theorem. Then, compared with the results of proportion differentiation control and conventional sliding mode control, the simulation results show that the proposed method can significantly reduce input signal chattering and improve the trajectory tracking performance of the PMSpM. Finally, experimental results are provided to validate the effectiveness of the proposed method.
Fabrication of soft x-ray monolithic Wolter mirror based on surface scanning measurement using touch probe
Authors: Kume Takehiro , Hiraguri Kentaro , Imamura Yoichi , Matsuzawa Yusuke , Saito Takahiro , Miyashita Hiroaki , Takeo Yoko , Senba Yasunori , Kishimoto Hikaru , Ohashi Haruhiko , Hashizume Hirokazu , Mimura Hidekazu
Published: June 2022

The monolithic Wolter mirror is an ideal optical device for focusing soft x rays to a submicron-sized spot, with the advantages of high efficiency, large acceptance, achromaticity, and robustness to alignment error. The fabrication process for this type of mirror has not been established because of the difficulty in highly accurate figure measurement of free-form surfaces with small radii of curvature and steep profiles. In this study, we employed tactile scanning measurement for surface characterization to fabricate a high-precision Wolter mirror. First, it was demonstrated that the touch probe measurement did not leave scratches on the raw surface of the mirror substrate. Next, the measurement capability of the surface profiler was assessed, and the data analysis conditions were determined. Finally, the Wolter mirror was fabricated through repeated figure correction based on the tactile measurement, and the figure error of the final surface was evaluated. Wave-optical simulations that used this error as reference suggested that the size of the beam focused by the mirror was equivalent to the theoretical value at 1000 eV. The reflected image with uniform intensity distribution obtained at SPring-8 also revealed the effectiveness of the present fabrication approach based on tactile measurement.
Enhanced electrochemical performance of vanadium carbide MXene composites for supercapacitors
Authors: Zahra Syedah Afsheen , Anasori Babak , Iqbal Muhammad Z. , Ravaux Florent , Al Tarawneh Mohammednoor , Rizwan Syed
Published: June 2022

Two-dimensional (2D) surface-terminated layered transition metal carbide MXenes with high electrochemical performance paved the way for robust energy storage supercapacitor devices. However, because of the 2D nature of the MXene flakes, self-restacking of 2D MXene flakes limits the use of all the flake functionalized surfaces in MXene electrodes. Here, we report the synthesis of V2CTx MXene and multiwall carbon nanotube (MWCNT)/V2CTx composites as a promising electrode material for hybrid energy storage devices. Our hybrid electrodes exhibited enhanced electrochemical performance and a gravimetric capacitance of 1842 F g−1 at a scan rate of 2 mV s−1, with a specific charge capacity of 62.5 A h/g. Moreover, the electrodes presented an excellent rate performance, durability, and retention capacity of 94% lasted up to 10 000 cycles. Density functional theory calculations provided electronic and structural properties of the considered MWCNT@V2CTx. Therefore, the introduction of MWCNTs enhanced the conductivity and reaction kinetics of the MXenes and facilitates the charge storage mechanism useful for next-generation smart energy storage devices.
Quantitative spatiotemporal density evolution of aluminum heated purely by monochromatic electrons
Authors: Coleman J. E. , Koglin J. E. , Morris H. E. , Ramey N. B. , Offermann D. T.
Published: June 2022

A spatially resolved air-wedge shearing interferometer and shadowgraph diagnostic provides measurements of electron density with a resolution of ∼40 μm. A ∼100-ns-long, monoenergetic electron bunch at 19.8 MeV and a current of 1.4 kA (8.5×1014 e−) heats 100-μm-thick aluminum (Al) foils in a 1-mm-spot to Te∼1 eV. A 5-ns-long, ∼60 mJ, frequency doubled Nd:YAG laser probes the dense Al plasma. Electron densities up to 1020cm−3 are resolved; the maximum resolvable density is limited by opacity, transmission, and spatial fringe density achievable with the detector. This diagnostic provides measurements of the total phase shift, transmission, and electron density. Several measurements at different time slices provide the ability to determine the velocity of the leading edge of the shadowgraph and compare it to the motion of different density shells. These measurements are also compared to radiation hydrodynamics simulations. A rough quantitative agreement is shown between the hydro simulations and the measurements; there are differences in the exact density distributions.
CH4, an ab initio story of an archetypal species
Authors: Kalemos Apostolos
Published: June 2022

The methane molecule is an archetypal species in the whole of chemistry for its ability to form four bonds that result in a myriad of compounds of chemical and biological importance. The hybrid orbitals involved in the bonding have been scrutinized for too many decades but only lately under the ab initio microscope. In this study, we detail the formation routes CHn + (4 − n) H → CH4 (n = 0, 1, and 2) both diabatically and adiabatically with the help of established computational techniques. The evolution of the Mulliken populations, of the non-adiabatic matrix coupling elements, and of the Kotani spin functions along the dissociation paths and finally the shape of the diabatic curves unambiguously point to a parental C atom of an excited 2s12p3 electronic configuration.
Entropy and freezing in Gaussian models
Authors: Koukiou Flora
Published: June 2022

A new definition of the freezing phenomenon is given in relation with the behavior of the entropy of Gibbs measures at low temperatures. In particular, for uncorrelated and log-correlated Gaussian models, we show that freezing arises when the entropy of the corresponding Gibbs measures vanishes.
Microlayer evaporation governs heat transfer enhancement during pool boiling from microstructured surfaces
Authors: Bongarala Manohar , Hu Han , Weibel Justin A. , Garimella Suresh V.
Published: June 2022

Enhancement of the rate of boiling heat transfer, a critically significant need across a range of industrial transport processes, can be achieved by the introduction of surface microstructures. However, the precise mechanism of such enhancement is not definitively understood. We establish microlayer evaporation from the imbibed liquid layer underneath the growing vapor bubbles as the key mechanism of enhancement in boiling heat transfer coefficient for microstructured surfaces. We experimentally characterize nucleate boiling heat transfer performance on silicon surfaces custom-fabricated with controlled microstructures using HFE-7100 as the working fluid. We then undertake an analytical prediction of the microlayer evaporation from the microstructured surface. A clear dependence of the measured boiling heat transfer coefficients from microstructures of different dimensions on the predicted evaporation heat transfer coefficients allows us to conclude that microlayer evaporation governs the boiling enhancement from microstructured surfaces.
Medium vacuum feasible displacement calibration of an optically levitated Duffing nonlinear oscillator
Authors: Tian Yuan , Zheng Yu , Liu Lyu-Hang , Guo Guang-Can , Sun Fang-Wen
Published: June 2022

Optical levitation in vacuum has been proved as a promising platform for precision measurement and research on microscopic thermodynamics and the macroscopic quantum system. The performance of these applications is highly determined by the detection of the trapped particle's displacement, which is linked with the detection signal through a calibration coefficient. However, it is still a challenge to get the calibration coefficient in medium vacuum. Here, we present a nonlinear method to obtain the calibration coefficient with high accuracy to fill the pressure gap between 5×10−3 and 50 mbar. By averaging the trajectory segments with the same initial displacement, we analyze the relationship between the nonlinearity induced frequency shift and the amplitude, where the calibration coefficient can be obtained without a priori knowledge about mass and temperature of the trapped particle or the assistance with external force. We further apply this method to detect the mass and density of the trapped nanoparticle and observe the mass variation under different pressures. Therefore, it will pave the way to study the physical processes in medium vacuum based on the precision measurement of nanoparticle's mass, density, and other properties.
Emission of anomalously hard x-ray radiation by a target upon exposition with an electron beam, ejected by a low-energy vacuum discharge with laser ignition
Authors: Paperny V. L. , Romanov I. V. , Kologrivov A. A. , Krasov V. I. , Korobkin Yu. V. , Rupasov A. A.
Published: June 2022

The characteristics of x-ray radiation of a target that is bombarded by a beam of accelerated electrons ejected by a low-power vacuum discharge with laser ignition are studied. It is shown that the maximum radiation energy exceeds the applied potential difference across the discharge gap by almost an order of magnitude and is inversely proportional to the mass of the cathode material ablated by laser radiation. The energy spectrum of x-ray radiation reconstructed from the radiation attenuation curve by filters-absorbers of various thicknesses showed that in the maximum acceleration mode the average energy of the main part of the spectrum is more than four times higher than the voltage across the discharge gap at the moment of beam emission. Possible mechanisms providing anomalous acceleration of electrons in the discharge are considered.
MEMS based bimorph optical temperature sensor
Authors: Shukla Kaushik , Datta Tanmoy , Sen Mrinal
Published: June 2022

The paper proposes a novel microcantilever based optical temperature sensor/calorimeter for use in applications requiring high-resolution measurements. The cantilever beam is made of bi-material that deflects in response to the change in temperature because of the difference that exists between the thermal expansion coefficients of the respective two materials. The deflection of the cantilever is then detected by an equivalent change in the optical intensity received by an optical setup. Analyses of the sensitivity have been carried out for different materials for the bimorph. The proposed sensor demonstrates a resolution of 110 nK as a temperature sensor and 0.5 pW as a calorimeter at 5% error for Al/SiO2 bimorph. Such a high sensitivity in the said context has never been reported earlier.
Toolbox for modeling frequency-domain photothermal experiments on multilayers
Authors: Chirtoc M. , Horny N.
Published: June 2022

A general expression (master equation, ME) is derived for the thermal impedance in photothermal experiments in a multilayer system, based on one-dimensional (1D) periodic heat diffusion. The ME in a compact form benefits from newly defined generalized, higher-order thermal reflection and transmission coefficients. The modeled system comprises seven layers among which a semitransparent sample and a transducer that integrates the temperature field within it (e.g., a pyroelectric sensor). The ME can be adapted to various experimental cell structures used in photopyroelectric, photoacoustic, photothermal radiometry, or thermoreflectance methods using volume- or surface-temperature detection, in view of spectroscopic applications or thermophysical properties determination. The derivation of special cases is facilitated by applying simple contraction rules to dimensionless quantities. Modeling multiple heat sources in the system is done by superposition of individual solutions. The possible extension of the 1D model to 2D geometry is demonstrated, in general, and practical criteria are discussed.
Topological acoustic tweezer and pseudo-spin states of acoustic topological insulators
Authors: Liu Peng , Li Hangyu , Zhou Zhitao , Pei Yongmao
Published: June 2022

Topological protection wave engineering in artificially structured media is at the forefront of metamaterials research. Acoustic analogs of electronic topological insulators have brought a lot of new opportunities for manipulating sound propagation and have attracted the attention of many scholars. A variety of artificial acoustic systems hosting topological edge states have been proposed. However, the pseudo-spin edge states at a boundary have not been clearly and intuitively characterized. In this article, we provide experimental verification of pseudo-spin states by the method of acoustic particle manipulation by using the rotation of the particle to describe the pseudo-spin sound field characteristics at the boundary of the acoustic topological insulator in detail. It indicates the existence of pseudo-spin–orbit coupling effects and pseudo-spin-related acoustic unidirectional transmission even if the defect exists. Furthermore, the pseudo-spin sound field can be used to control the rotation of multiple particles and droplets. This kind of topological acoustic tweezer with defect immunity has great application potential in the fields of biomedicine and materials science.
Network resilience of non-hub nodes failure under memory and non-memory based attacks with limited information
Authors: Dong Gaogao , Wang Nan , Wang Fan , Qing Ting , Liu Yangyang , Vilela André L. M.
Published: June 2022

Previous studies on network robustness mainly concentrated on hub node failures with fully known network structure information. However, hub nodes are often well protected and not accessible to damage or malfunction in a real-world networked system. In addition, one can only gain insight into limited network connectivity knowledge due to large-scale properties and dynamic changes of the network itself. In particular, two different aggression patterns are present in a network attack: memory based attack, in which failed nodes are not attacked again, or non-memory based attack; that is, nodes can be repeatedly attacked. Inspired by these motivations, we propose an attack pattern with and without memory based on randomly choosing n non-hub nodes with known connectivity information. We use a network system with the Poisson and power-law degree distribution to study the network robustness after applying two failure strategies of non-hub nodes. Additionally, the critical threshold 1−pc and the size of the giant component S are determined for a network configuration model with an arbitrary degree distribution. The results indicate that the system undergoes a continuous second-order phase transition subject to the above attack strategies. We find that 1−pc gradually tends to be stable after increasing rapidly with n. Moreover, the failure of non-hub nodes with a higher degree is more destructive to the network system and makes it more vulnerable. Furthermore, from comparing the attack strategies with and without memory, the results highlight that the system shows better robustness under a non-memory based attack relative to memory based attacks for n>1. Attacks with memory can block the system’s connectivity more efficiently, which has potential applications in real-world systems. Our model sheds light on network resilience under memory and non-memory based attacks with limited information attacks and provides valuable insights into designing robust real-world systems.
Bending effect on the synaptic behavior of WO3-based flexible memristor under variable temperatures
Authors: Qi Shuai-Shuai , Yang Fei , Li Jian-Chang
Published: June 2022

We systematically study the fatigue failure of the Ag/Poly (3-hexylthiophene-2,5-diyl)(P3HT)/WO3/ITO/PET flexible memristor under variable temperatures, which simulates essential synaptic learning functions. The theoretical calculations and finite element analysis results indicate that the P3HT/WO3 interface plays a key role in device fatigue failure at variable temperatures. As the temperature dropped from 100 to −30 °C, a significant decrease in the loosely adsorbed polymer chains and flattened chains occurs at the P3HT/WO3 interface and thus leads to the deterioration of the P3HT/WO3 interface. The weak P3HT/WO3 interfacial bonding substantially accelerates the crack propagation under low-temperature flexural cycles, which will ultimately cause the device to deteriorate. Our work may provide some useful information for future achievement of flexible memory synapses utilized in cryogenic environments.
Emergency rate-driven control for rotor angle instability in power systems
Authors: K. S. Suchithra , E. A. Gopalakrishnan , Kurths Jürgen , Surovyatkina E.
Published: June 2022

Renewable energy sources in modern power systems pose a serious challenge to the power system stability in the presence of stochastic fluctuations. Many efforts have been made to assess power system stability from the viewpoint of the bifurcation theory. However, these studies have not covered the dynamic evolution of renewable energy integrated, non-autonomous power systems. Here, we numerically explore the transition phenomena exhibited by a non-autonomous stochastic bi-stable power system oscillator model. We use additive white Gaussian noise to model the stochasticity in power systems. We observe that the delay in the transition observed for the variation of mechanical power as a function of time shows significant variations in the presence of noise. We identify that if the angular velocity approaches the noise floor before crossing the unstable manifold, the rate at which the parameter evolves has no control over the transition characteristics. In such cases, the response of the system is purely controlled by the noise, and the system undergoes noise-induced transitions to limit-cycle oscillations. Furthermore, we employ an emergency control strategy to maintain the stable non-oscillatory state once the system has crossed the quasi-static bifurcation point. We demonstrate an effective control strategy that opens a possibility of maintaining the stability of electric utility that operates near the physical limits.
Researchers’ transfer network reveals the evolution of national science and technology capabilities
Authors: Yang Yating , Zhao Chengli , Zhang Xue , Wang Zhengming
Published: June 2022

Science and technology capability refers to the comprehensive capability of all factors that affect the development of science and technology, mainly referring to human and material factors related to science and technology, among which human resources are the foundation and driving force. Therefore, researchers become a unique research perspective for the evaluation of national science and technology capabilities. Taking the integrated circuit field as the analysis case, this article proposed a researchers’ transfer network model based on the online open source literature database. From the published literature information, the model obtains the researchers’ transfer network that has a core-periphery structure. The core nodes are the European Union, the United States, China, etc., and these nodes are the most closely connected. A country/region role evolution model is also proposed, which reveals the characteristics of the role evolution of the European Union, the United States, China, and other countries from the perspective of researchers’ transfer, especially their transfer between countries.
Engineering the charge extraction and trap states of Sb2S3 solar cells
Authors: Qi Yiming , Li Yanyan , Lin Qianqian
Published: June 2022

Antimony sulfide (Sb2S3) as a binary chalcogenide has emerged as a promising candidate for next-generation thin-film photovoltaics. Although breakthroughs have been made in terms of device performance in recent years, the power conversion efficiency is still far from the Shockley–Queisser limit. It is mainly attributed to the poor charge transport and abundant defects, which deteriorate the fill factor and result in grievous open-circuit voltage loss. Here, we improved the device performance through a synergetic approach: (i) by introducing ZnSnO3 as the second electron transport layer, the current leakage was effectively reduced, and the charge extraction was enhanced; then, (ii) the prepared Sb2S3 films were treated via a low-temperature and short-time post-treatment with thiourea, which significantly suppressed the carrier recombination and increased the open-circuit voltage. More importantly, we systematically analyzed the trap features of the Sb2S3 films with/without treatment, mainly including the trap density, trap level, and trap capture cross section. We found that defects near the surface due to elemental inhomogeneity by the hydrothermal method could be effectively passivated, and defect-assisted recombination was suppressed after the thiourea treatment.
Investigating the effects of electron bounce-cyclotron resonance on plasma dynamics in capacitive discharges operated in the presence of a weak transverse magnetic field
Authors: Sharma Sarveshwar , Patil Sanket , Sengupta Sudip , Sen Abhijit , Khrabrov Alexander , Kaganovich Igor
Published: June 2022

Recently, Patil et al. [Phys. Rev. Res. 4, 013059 (2022)] have reported the existence of an enhanced operating regime when a low-pressure (5 mTorr) capacitively coupled discharge (CCP) is driven by a very high radio frequency (60 MHz) source in the presence of a weak external magnetic field applied parallel to its electrodes. Their particle-in-cell simulations show that a significantly higher bulk plasma density and ion flux can be achieved at the electrode when the electron cyclotron frequency equals half of the applied radio frequency for a given fixed voltage. In the present work, we take a detailed look at this phenomenon and further delineate the effect of this “electron bounce-cyclotron resonance (EBCR)” on the electron and ion dynamics of the system. We find that the ionization collision rate and stochastic heating are maximum under resonance condition. The electron energy distribution function also indicates that the population of tail-end electrons is highest for the case where EBCR is maximum. Formation of electric field transients in the bulk plasma region is also seen at lower values of applied magnetic field. Finally, we demonstrate that the EBCR-induced effect is a low-pressure phenomenon and weakens as the neutral gas pressure increases. The potential utility of this effect to advance the operational performance of CCP devices for industrial purposes is discussed.
U
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h
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-free modules over the super-Galilean conformal algebras
Authors: Xie Qiang , Sun Jiancai , Yang Hengyun
Published: June 2022

In this paper, we study non-weight modules over the super-Galilean conformal algebra. We construct and classify U(H)-free modules of rank 1 over the Ramond-type algebra and U(h)-free modules of rank 2 over the Neveu–Schwarz-type algebra, where H is a subalgebra of the Ramond-type algebra and h is the Cartan algebra of the Neveu–Schwarz-type algebra. We find that these modules are reducible and isomorphic.
L2Ti0.85(Mg1/3Nb2/3)0.15O3/MgTiO3/L2Ti0.85 (Mg1/3Nb2/3)0.15O3 tri-layer co-fired microwave dielectric ceramics: A strategy to suppress non-linear variation of resonant frequency with temperature and achieve a high Q value
Authors: Li Lingxia , He Xuerui , Yue Tao , Zhan Yu , Du Mingkun
Published: June 2022

In many microwave dielectric ceramics systems, like MgTiO3–CaTiO3, MgTiO3–SrTiO3, and tri-layer MgTiO3/TiO2/MgTiO3, the resonant frequency shows a non-linear variation over a wide temperature range (−40 – 105 °C), indicating that the negative τf (−40 – 25 °C) value deviates from zero when the positive τf (25–105 °C) value is tuned to zero. To suppress the non-linear variation of resonant frequency in the range of −40 – 105 °C, a well-established and efficacious method has been proposed by introducing Li2Ti0.85(Mg1/3Nb2/3)0.15O3 ceramic to the MgTiO3 system. Furthermore, a tri-layer architecture ceramic was designed to improve the dielectric properties. Compared with randomly distributed samples, the Q × f value can be increased by up to 51%. Moreover, the electric field distribution was simulated by the finite element method with the aid of the eigenmode solver of high frequency structure simulator (HFSS) to clarify the dielectric mechanism and predict the microwave dielectric characteristics of the tri-layer structure ceramics. Finally, tri-layer Li2Ti0.85(Mg1/3Nb2/3)0.15O3/MgTiO3/Li2Ti0.85(Mg1/3Nb2/3)0.15O3 ceramic with wide temperature stability and high Q × f value was obtained [εr = 18.4, Q × f = 85 000 GHz, τf+ = −3.8 ppm/°C (25–105 °C), τf− = 4.0 ppm/°C (−40 – 25 °C)], which refines the theory of non-linear variation of resonant frequency and holds promise for application in the 5G communication system.
Entropy and order work together in an artificial spin ice
Authors: Miller Johanna L.
Published: June 2022

The very factor that propels most of the universe toward disorder pushes an array of nanomagnets into a visibly ordered state.
Ultrafast two-photon fluorescence imaging of cerebral blood circulation in the mouse brain in vivo
Authors: Meng Guanghan , Zhong Jian , Zhang Qinrong , Wong Justin S. J. , Wu Jianglai , Tsia Kevin K. , Ji Na
Published: June 2022

Significance

Characterizing blood flow by tracking individual red blood cells as they move through vessels is essential for understanding vascular function. With high spatial resolution, two-photon fluorescence microscopy is the method of choice for imaging blood flow at the cellular level. However, its application is limited to a low flow speed regimen in anesthetized animals by its slow focus scanning mechanism. Using an ultrafast scanning module, we demonstrated two-photon fluorescence imaging of blood flow at 1,000 two-dimensional frames and 1,000,000 one-dimensional line scans per second in the brains of awake mice. These ultrafast measurements enabled us to study hemodynamic and fluid mechanical regimens beyond the reach of conventional methods.
A predictive microfluidic model of human glioblastoma to assess trafficking of blood–brain barrier-penetrant nanoparticles
Authors: Straehla Joelle P. , Hajal Cynthia , Safford Hannah C. , Offeddu Giovanni S. , Boehnke Natalie , Dacoba Tamara G. , Wyckoff Jeffrey , Kamm Roger D. , Hammond Paula T.
Published: June 2022

Significance

The blood–brain barrier represents a major therapeutic challenge for the treatment of glioblastoma, and there is an unmet need for in vitro models that recapitulate human biology and are predictive of in vivo response. Here, we present a microfluidic model of vascularized glioblastoma featuring a tumor spheroid in direct contact with self-assembled vascular networks comprising human endothelial cells, astrocytes, and pericytes. This model was designed to accelerate the development of targeted nanotherapeutics and enabled rigorous assessment of a panel of surface-functionalized nanoparticles designed to exploit a receptor overexpressed in tumor-associated vasculature. Trafficking and efficacy data in the in vitro model compared favorably to parallel in vivo data, highlighting the utility of the vascularized glioblastoma model for therapeutic development.
Artificial neuromorphic cognitive skins based on distributed biaxially stretchable elastomeric synaptic transistors
Authors: Shim Hyunseok , Jang Seonmin , Thukral Anish , Jeong Seongsik , Jo Hyeseon , Kan Bin , Patel Shubham , Wei Guodan , Lan Wei , Kim Hae-Jin , Yu Cunjiang
Published: June 2022

Significance

Enabling distributed neurologic and cognitive functions in soft deformable devices, such as robotics, wearables, skin prosthetics, bioelectronics, etc., represents a massive leap in their development. The results presented here reveal the device characteristics of the building block, i.e., a stretchable elastomeric synaptic transistor, its characteristics under various levels of biaxial strain, and performances of various stretchy distributed neuromorphic devices. The stretchable neuromorphic array of synaptic transistors and the neuromorphic imaging sensory skin enable platforms to create a wide range of soft devices and systems with implemented neuromorphic and cognitive functions, including artificial cognitive skins, wearable neuromorphic computing, artificial organs, neurorobotics, and skin prosthetics.
Origins of Dogon NP tonosyntax
Authors: Heath Jeffrey
Published: June 2022

Like other complex morphosyntactic and morphophonological structures that are endemic to single language families, Dogon NP tonosyntax is the result of the fortuitous interlocking of diachronically unrelated processes and constructions. It arose due to the following combination: (a) right-headed prosodic pattern in noun-modifier sequences; (b) loss of numeral classifiers which had previously protected nouns from the right-headed prosodic pattern when followed by numerals; and (c) transfer of tones from possessors to following possessums. Although none of these phenomena were semantically driven, the resulting configuration could only be reinterpreted by native speakers in semantic terms, creating a completely new system unique to Dogon. In spite of having arisen accidentally, this tonosyntactic system is quite stable. One of its benefits is the unusual solution it provided (at no extra charge) to a perennial problem in the design of relative constructions.
Anisotropic upper critical field, Seebeck and Nernst coefficient of Nb0.20Bi2Se3 superconductor
Authors: Sharma Shailja , Yadav C S
Published: June 2022

We present the magneto-transport and the thermoelectric (Seebeck and Nernst coefficient) studies of the Nb-doped Bi2Se3 superconductor. The angle-dependent magnetoresistance study highlights the anisotropy of upper critical field (Hc

2) for in-plane and out-of-plane magnetic field orientation with the anisotropy parameter Γ ∼ 1.3. The estimated value of the carrier concentration (∼1019 cm−3) for Nb0.2Bi2Se3 is one order larger than for Bi2Se3. Doping of Nb shows a significant decrease in the Seebeck coefficient value and the estimated Fermi temperature of the three-dimensional Fermi surface at the centre of Brillouin zone in the zero-temperature limit enhances by ∼4 times in comparison to pristine Bi2Se3. We have observed a large value (∼2.3 µV K−1T−1) of Nernst coefficient for Bi2Se3 at room temperature, which decreases with Nb doping (∼0.5 µV K−1 T−1).
Superconductivity in silicon
Authors: Moun Monika , Sheet Goutam
Published: June 2022

Silicon, one of the most abundant elements found on Earth, has been an excellent choice of the semiconductor industry for ages. Despite its remarkable applications in modern semiconductor-based electronic devices, the potential of cubic silicon in superconducting electronics remained a challenge because even heavily doped silicon crystals do not superconduct under normal conditions. It is apparent that if superconductivity can be introduced in cubic silicon, that will bring a breakthrough in low-dissipation electronic circuitry. Motivated by this, attempts have been made by several research groups to induce superconductivity in silicon through a number of different routes. Some of the other structural phases of silicon like β-Sn and simple hexagonal are, however, known to display superconductivity. In the present review article, various theoretical and experimental aspects of superconductivity in silicon are discussed. Superconductivity in different phases and different structural forms of silicon are also reviewed. We also highlight the potential of superconducting phases of silicon for technological applications in superconducting nano-electronics.
Improvement in hyperexpression with a combination of truncated scmp promoter and Streptomyces lividans
Authors: Uraji Misugi , Yang Lingli , Hatanaka Tadashi
Published: June 2022

We have previously reported a powerful promoter from the Streptomyces cinnamoneus TH-2 strain named ‘scmp’ and created an expression vector of pTONA5a for expression using S. lividans. The full-length scmp promoter sequence consists of 424 bp upstream of a metalloendoprotease gene in the S. cinnamoneus TH-2 genome. The promoter works in the presence of inorganic phosphate and glucose. In this study, we present the essential region of the scmp promoter (promoter C), which lacks 358 bp of the 5′ region of the full-length promoter. Promoter C was very short and contained only 63 bp. Using promoter C, we succeeded in the extracellular production of the Streptomyces enzymes of leucine aminopeptidase, ferulic acid esterase, and transglutaminase, which possessed signal peptides for secretion via the type II secretion pathway, at high levels.
Comparison of right hemicolectomies with and without complete mesocolic excision (CME)
Authors: Cathomas M , Galli R , Heigl A , Lamm S , Glaser C , Cathomas G , Rosenberg R
Published: June 2022

Objective

Since the concept of complete mesocolic excision (CME) in right hemicolectomies was introduced, it is still under debate if all patients require this radical technique.

Methods

Patients with adenocarcinoma of the colon undergoing right hemicolectomies at our hospital were retrospectively analyzed and stratified in a non-CME group (08/2014-04/2018) and a CME group (05/2018-11/2021). Patients were compared in regard to clinical, histopathological and prognostic parameters. CME were classified according to Benz et al.

Results

A total of 130 right hemicolectomies were performed, 33 (25.4%) patients were excluded due to other pathologies or emergency patients. Finally, 97 patients were included (53 in the CME group, 39 in the non-CME group). No difference in patient's characteristics were found except more male patients in the CME group (20 vs. 6; p=0.02). Tumors in the CME group were mainly located in the colon ascendens (66.0%), in the non-CME group in the coecum (48.7%; n.s.). In the CME group, 26 of 53 (49.1%) patients were operated laparoscopically compared to 10 of 39 (25.6%) patients in the non-CME group. Da Vinci system were used exclusively in the CME group (5 of 53 (9.4%); p=0.003). TNM classification, histology and UICC stadium showed no significant difference. In total, 50 (94.3%) surgical specimen were classification either as CME 0 or 1. In average, 35.2 lymph nodes (8.2% positive) were found in the CME group compared to 32.7 (16.2% positive) lymph nodes in the non-CME group (p=0.9). No relevant intraoperative complications occurred in both groups. Distance of the mesocolon were available in 39 (73.6%) patients in the CME group and 34 (37.1%) in the non-CME group; the distance tended to be longer in the CME group (mean 116.0 mm in CME group vs. 96.6 mm in non-CME group; p=0.09). Follow-up were 336.4 days in CME-group and 1210.4 days in the non-CME group. In the follow-up, 2 (5.1%) patients in the non-CME group developed a local recurrence in the smaller pelvis. No local recurrence occurred in the CME group (p=0.18). Distant metastasis occurred in 5 of 53 (9.4%) patients in the CME group and in 2 of 39 (5.4%) patients in the non-CME group (p=0.7).

Conclusion

This study shows that the benefit for CME in all performed right hemicolectomies is marginal and that the surgical standards was already high in the pre-CME era.
Between Us and Them: Deaf Bedouin Women’s Perception of the Role of Social Workers
Authors: Allassad Alhuzail Nuzha , Levinger Miriam
Published: June 2022

Israel’s Bedouin minority, with unique socio-demographic and cultural characteristics, has a higher incidence of deafness than that reported worldwide. Because they lack suitable social services, local access to information and public transportation, deaf Bedouins live in a challenging social context. Most social workers are hearing people untrained regarding this population and lacking proficiency in sign language. This complicates the therapeutic encounter. Most of the Bedouin service users are women, who contend with triple discrimination deriving from their gender, disability and socio-ethnic affiliation. Therefore, this qualitative study using semi-structured interviews of twenty-three deaf Bedouin women focuses on how they perceive the social workers in the local social services bureaus. We found that they view the social worker as a person to whom one can complain, who is supposed to look out for one’s rights, whom it is unpleasant to meet and who abandons them in a struggle. They also expressed ambivalent feelings towards their social workers: anger and frustration but also compassion and pity. The discussion focuses on the role of the social worker, the influence of acculturation and the three-way therapeutic encounter. Recommendations include equipping social workers with communication skills, knowledge about the population and skills for changing oppressive policy.
Increased TNF-α production in response to IL-6 in patients with systemic inflammation without infection
Authors: Cabrera-Rivera Graciela L , Madera-Sandoval Ruth L , León-Pedroza José Israel , Ferat-Osorio Eduardo , Salazar-Rios Enrique , Hernández-Aceves Juan A , Guadarrama-Aranda Uriel , López-Macías Constantino , Wong-Baeza Isabel , Arriaga-Pizano Lourdes A
Published: June 2022

Acute systemic inflammation can lead to life-threatening organ dysfunction. In patients with sepsis, systemic inflammation is triggered in response to infection, but in other patients, a systemic inflammatory response syndrome (SIRS) is triggered by non-infectious events. IL-6 is a major mediator of inflammation, including systemic inflammatory responses. In homeostatic conditions, when IL-6 engages its membrane-bound receptor on myeloid cells, it promotes pro-inflammatory cytokine production, phagocytosis, and cell migration. However, under non-physiologic conditions, such as SIRS and sepsis, leucocyte dysfunction could modify the response of these cells to IL-6. So, our aim was to evaluate the response to IL-6 of monocytes from patients diagnosed with SIRS or sepsis. We observed that monocytes from patients with SIRS, but not from patients with sepsis, produced significantly more TNF-α than monocytes from healthy volunteers, after stimulation with IL-6. Monocytes from SIRS patients had a significantly increased baseline phosphorylation of the p65 subunit of NF-κB, with no differences in STAT3 phosphorylation or SOCS3 levels, compared with monocytes from septic patients, and this increased phosphorylation was maintained during the IL-6 activation. We found no significant differences in the expression levels of the membrane-bound IL-6 receptor, or the serum levels of IL-6, soluble IL-6 receptor, or soluble gp130, between patients with SIRS and patients with sepsis. Our results suggest that, during systemic inflammation in the absence of infection, IL-6 promotes TNF-α production by activating NF-κB, and not the canonical STAT3 pathway.
Moving without sensory feedback: online TMS over the dorsal premotor cortex impairs motor performance during ischemic nerve block
Authors: Bruno Valentina , Castellani Nicolò , Garbarini Francesca , Christensen Mark Schram
Published: June 2022

The study investigates the role of dorsal premotor cortex (PMd) in generating predicted sensory consequences of movements, i.e. corollary discharges. In 2 different sessions, we disrupted PMd and parietal hand’s multisensory integration site (control area) with transcranial magnetic stimulation (TMS) during a finger-sequence-tapping motor task. In this TMS sham-controlled design, the task was performed with normal sensory feedback and during upper-limb ischemic nerve block (INB), in a time-window where participants moved without somatosensation. Errors and movement timing (objective measures) and ratings about movement perception (subjective measures) were collected. We found that INB overall worsens objective and subjective measures, but crucially in the PMd session, the absence of somatosensation together with TMS disruption induced more errors, less synchronized movements, and increased subjective difficulty ratings as compared with the parietal control session (despite a carryover effect between real and sham stimulation to be addressed in future studies). Contrarily, after parietal area interference session, when sensory information is already missing due to INB, motor performance was not aggravated. Altogether these findings suggest that the loss of actual (through INB) and predicted (through PMd disruption) somatosensory feedback degraded motor performance and perception, highlighting the crucial role of PMd in generating corollary discharge.
Robust sex differences in functional brain connectivity are present in utero
Authors: Cook Kevin M , De Asis-Cruz Josepheen , Lopez Catherine , Quistorff Jessica , Kapse Kushal , Andersen Nicole , Vezina Gilbert , Limperopoulos Catherine
Published: June 2022

Sex-based differences in brain structure and function are observable throughout development and are thought to contribute to differences in behavior, cognition, and the presentation of neurodevelopmental disorders. Using multiple support vector machine (SVM) models as a data-driven approach to assess sex differences, we sought to identify regions exhibiting sex-dependent differences in functional connectivity and determine whether they were robust and sufficiently reliable to classify sex even prior to birth. To accomplish this, we used a sample of 110 human fetal resting state fMRI scans from 95 fetuses, performed between 19 and 40 gestational weeks. Functional brain connectivity patterns classified fetal sex with 73% accuracy. Across SVM models, we identified features (functional connections) that reliably differentiated fetal sex. Highly consistent predictors included connections in the somatomotor and frontal areas alongside the hippocampus, cerebellum, and basal ganglia. Moreover, high consistency features also implicated a greater magnitude of cross-region connections in females, while male weighted features were predominately within anatomically bounded regions. Our findings indicate that these differences, which have been observed later in childhood, are present and reliably detectable even before birth. These results show that sex differences arise before birth in a manner that is consistent and reliable enough to be highly identifiable.
On the importance of concomitant conditions: light and conspecific presence modulate prey response to predation cue
Authors: Jermacz Łukasz , Kobak Jarosław
Published: June 2022

Assessment of individual costs of the anti-predator defence translating into changes in population parameters is meagre. This is because prey responses are likely to be modulated by additional factors, commonly present in the environment, but often neglected in experimental studies. To evaluate the effect of external factors on prey behavior and physiology, we exposed amphipods Dikerogammarus villosus and Gammarus jazdzewskii to the predation cue of Perca fluviatilis in different densities and light conditions. Singletons of both species exposed to the predation cue in light modified their oxygen consumption (D. villosus: reduction, G. jadzewskii: increase) compared to their respiration in predator-free conditions. However, in the presence of conspecifics or in darkness, their respiration became insensitive to the predation cue. On the other hand, the swimming activity of prey was reduced in the presence of the predation cue irrespective of prey density and light conditions, but singletons were consistently more active than groups. Thus, external factors, such as conspecifics and darkness, constantly or periodically occurring in the field, may reduce the costs of predator non-consumptive effects compared to the costs measured under laboratory conditions (in light or absence of conspecifics). Moreover, we showed that behavioral and physiological parameters of prey may change differently in response to predation risk. Thus, conclusions drawn on the basis of single defence mechanisms and/or results obtained in artificial conditions, not reflecting the environmental complexity, strongly depend on the experimental design and endpoint selection and therefore should be treated with care.