bluuebunny/crossref_metadata_2025 huggingface dataset:
Finite-difference multiple fluid solution for source-driven rotation in highly magnetized linear plasma device
Authors: Rubin T. , Kolmes E. J. , Ochs I. E. , Mlodik M. E. , Fisch N. J.
Published: December 2021

The rotation profile of a magnetized plasma cylinder composed of multiple fluids is investigated analytically, expanding on previous results. The analytic steady-state solution is used as a benchmark for a time-dependent multiple-fluid finite-difference code, MITNS: Multiple-Ion Transport Numerical Solver. Magnetic field evolution is taken into account, both analytically and numerically. Its details are shown to be of importance when particles are allowed out of the domain. MITNS reproduces the asymptotic expansion results for a small parameter δ⋘1. For me/mi∼δ≪1, a slightly different regime, dominated by viscosity-induced transport of ions, is found numerically and analytically. This verification supports the use of this code for more complex time-dependent calculations in the future. Additionally, we derive the angular velocity profile of each species due to radial particle and charge fluxes of various strengths.
A compact nanosecond pulse generator for x-ray radiographies
Authors: Zhou Lin , Ye Mingtian , Qi Jianming , Chu Yanyun , Wang Zhen
Published: December 2021

A compact nanosecond pulse generator was developed, aiming at producing high-energy flash x rays with a long lifetime. The generator was designed on the basis of a 0.67-ns pulse forming line (PFL), which is charged to ∼700 kV by an air core Tesla transformer and switched by a fast spark gap. The Tesla transformer consists of a single turn primary coil surrounding a 44-turn secondary coil using no magnetic cores. 2D magnetostatic and electrostatic simulations were carried out, and the inductance and stray capacitance of the transformer were calculated. The transformer was powered by a 40-nF capacitor bank via a hydrogen thyratron. An effective coupling co-efficiency keff of 0.55 was achieved. The PFL voltage reached its second peak of 680 kV in 395 ns when the capacitor bank was switched at 25 kV. A nanosecond pulse with a peak voltage of 510 kV, a peak power of 2.6 GW, and a pulse width of 2.1 ns was generated on a 100-Ω ceramic resistor, which is going to be replaced by a vacuum x-ray tube. Since the pulse energy is small, the x-ray tube is expected to have a long lifetime. The generator is 285 mm in diameter, 800 mm in length, and 35 kg in weight, providing a compact means for high-energy x-ray radiographies both in scientific research and industrial applications.
Electrostatic weak turbulence theory for warm magnetized plasmas
Authors: Yoon Peter H. , Ziebell Luiz F.
Published: December 2021

Electrostatic weak turbulence theory for plasmas immersed in an ambient magnetic field is developed by employing a hybrid two-fluid and kinetic theories. The nonlinear susceptibility response function is calculated with the use of warm two-fluid equations. The linear dispersion relations for longitudinal electrostatic waves in magnetized plasmas are also obtained within the warm two-fluid theoretical scheme. However, dissipations that arise from linear and nonlinear wave–particle interactions cannot be discussed with the macroscopic two-fluid theory. To compute such collisionless dissipation effects, linearized kinetic theory is utilized. Moreover, a particle kinetic equation, which is necessary for a self-consistent description of the problem, is derived from the quasilinear kinetic theory. The final set of equations directly generalizes the electrostatic weak turbulence theory in unmagnetized plasmas, which could be applied for a variety of problems including the electron beam–plasma interactions in magnetized plasma environments.
Features of FeB pair light-induced dissociation and repair in silicon n+-p-p+ structures under ultrasound loading
Authors: Olikh O. , Kostylyov V. , Vlasiuk V. , Korkishko R. , Olikh Ya. , Chupryna R.
Published: December 2021

The experimental research in ultrasound impact on iron–boron pair transformation in silicon n+-p-p+ structures has revealed the decrease in concentration of pairs dissociated by light, as well as in the time of pair associations. The FeB pair changes were monitored by measuring short circuit current kinetics. The ultrasound influence was investigated at different light intensities, temperatures, frequencies, and power of acoustic waves. The possible mechanisms underlying the revealed effects were analyzed.
Electroosmotic flow of viscoelastic fluid through a microchannel with slip-dependent zeta potential
Authors: Vasista Kasavajhula Naga , Mehta Sumit Kumar , Pati Sukumar , Sarkar Sandip
Published: December 2021

We investigate flow characteristics for an electroosmotic flow of viscoelastic fluids through a hydrophobic plane microchannel, considering the coupled effect of interfacial slip and zeta potential. We employ a simplified Phan–Thien–Tanner model to describe the constitutive behavior of the fluid. The governing equations are solved analytically to obtain electric double layer (EDL) potential distribution, flow velocity, flow rate, stresses, and viscosity. We have compared the obtained analytical flow field with the established theoretical and experimental works at the limiting cases. We demonstrate that ignoring the effect of the interfacial slip on zeta potential will lead to underprediction of the flow rate, and this underprediction is amplified with the increase in the Deborah number, decrease in the EDL thickness, and increase in the slip coefficient. Moreover, the relative flow rate augmentation by the rheological behavior strictly depends on the range of slip coefficients with the change in the EDL thickness. Accordingly, we have identified three regions of the slip coefficient. In addition, the viscosity near the wall decreases with the slip coefficient for the slip dependent zeta potential model. In contrast, the normal and shear stresses are augmented with the slip coefficient. Outcomes of the present investigation may help one to understand the enhanced flow behavior for the transport of complex fluids through a hydrophobic microchannel.
Benzvalyne: Real or imaginary?
Authors: Poland Kimberley N. , Westbrook Brent R. , Magers David H. , Fortenberry Ryan C. , Davis Steven R.
Published: December 2021

Benzvalyne (C6H4) is a bicyclic structural isomer of o-benzyne that some typically trusted levels of theory do not report as a minimum on the potential energy surface (PES). The structure was found to be a C2v minimum at the MCSCF, MP2, coupled-cluster single double, coupled-cluster single double triple (CCSDT)-1b, and CCSDT-2 levels of theory. Density functionals at the B3LYP-D3, B2PLYP-D3, and M06-D3 levels also produced a minimum structure. On the other hand, the CCSD(T), CCSD(T)-F12, and CCSDT-1a methods produced a single imaginary frequency for benzvalyne. However, the increase in the correlation for the CCSDT-1b and CCSDT-2 methods implies that benzvalyne is, in fact, a true, if highly strained, minimum on the PES. The C–C≡C bond angle was found to be only 108°; this angle is 180° for an unstrained C–C≡C triple bond moiety. As a result, the strain energy is notably high at 159 kcal mol−1. Comparing the strain energy of the rest of the molecule gives a strain energy of 92 kcal mol−1 for this triple bond region alone. The computed harmonic frequencies contain normal modes consisting of two hindered rotations of the C≡C diatomic part of the molecule, suggesting that the dissociation of this diatomic from the bicylobutane moiety may be important in the chemistry of this molecule. Because the putative C2v minimum is predicted to have a significant dipole moment (2.6 D), benzvalyne may be detectable in TMC-1, where the related o-benzyne molecule has recently been observed by radio astronomy.
Analysis of flow-field characteristics and pressure gain in air-breathing rotating detonation combustor
Authors: Wu Kevin , Zhang Shu-jie , She Da-wen , Wang Jian-ping
Published: December 2021

Three-dimensional numerical simulations are performed on air-breathing rotating detonation combustors with detailed H2/air chemistry. Detonation-related flow structures and pressure gain performance have been investigated. Emphasis is placed on the effects of the upstream oblique shock wave that is attached with detonation. This unsteady oblique shock wave is found to rotate along the chamber in the pre-detonation region. The angle of the upstream oblique shock wave shows a negative correlation with chamber pressure. Moreover, particle trajectory analysis shows that particles cross the unsteady upstream oblique shock wave twice or three times before being consumed by detonation, with obvious deflections in the radial direction due to the curvature effect, while particles collide with the downstream oblique shock wave in the post-detonation region once. At the exit, more than 96% of kinetic energy is still concentrated in the axial direction. Furthermore, the pressure gain performance is investigated by the integral of total pressure over the averaged area in the axial direction and individual particles. The results show that detonation-related flow structures in the current chamber configuration fail to achieve positive pressure gain. −17.2%, −16.4%, and −17.8% of total pressure gain are obtained in three numerical simulations. Further analysis shows that though the total pressure of particles increases instantly when encountering the upstream oblique shock wave, 25% of total pressure is lost before detonation combustion due to the large angle of the upstream oblique shock wave and the geometry. The cumulative effect of the pre-detonation region on the total pressure is equivalent to flows with Mach 1.94 crossing a normal shock wave.
How the experience of different non-acute bed-based mental health services reinforces the need for tailored stepped care
Authors: Hopkins Liza , Lee Stuart , Collister Laura , Smart Paul , Birks Susanne
Published: December 2021

Objective Stepped care as a model of provision of mental health services has been frequently described from clinical or health administration perspectives, but less is known about the consumer perspective of stepped models of care. Method Qualitative interviews were undertaken with 18 consumers across a range of residential mental health services in Melbourne, Australia. Interviews were designed to help understand consumers’ needs and experiences in navigating different services to meet their needs at different times in their mental health journey. Results Consumers experience fluctuations in their mental state that are best responded to by having access to a range of services, as well as to services that can respond flexibly to changing needs. Consumers do not necessarily progress through stepped care in a linear or step-up, step-down fashion. Conclusion Stepped care services need to be flexible in accommodating people along a continuum of care and responsive to where the consumer is at on their journey, rather than predetermining the trajectory of care. What is known about the topic? Stepped care has been identified as a critical component of comprehensive mental health care, bridging the gap between primary care and acute mental health services. The components of effective stepped care models have been broadly articulated, but the experience of moving through different components of care in response to changing needs has not previously been well described. What does the paper add? This paper presents consumer perspectives on a model of stepped care that is designed to respond flexibly to the changing needs of consumers, rather than representing a linear model of progress through the system. What are the implications for practitioners? Mental health services are increasingly grappling with provision of care to the ‘missing middle’: people with chronic mental illness yet not in an acute phase requiring in-patient hospital care. This paper presents a model of stepped care that responds to the fluctuating needs of consumers
Reporting all results efficiently: A RARE proposal to open up the file drawer
Authors: Laitin David D. , Miguel Edward , Alrababa’h Ala’ , Bogdanoski Aleksandar , Grant Sean , Hoeberling Katherine , Hyunjung Mo Cecilia , Moore Don A. , Vazire Simine , Weinstein Jeremy , Williamson Scott
Published: December 2021

While the social sciences have made impressive progress in adopting transparent research practices that facilitate verification, replication, and reuse of materials, the problem of publication bias persists. Bias on the part of peer reviewers and journal editors, as well as the use of outdated research practices by authors, continues to skew literature toward statistically significant effects, many of which may be false positives. To mitigate this bias, we propose a framework to enable authors to report all results efficiently (RARE), with an initial focus on experimental and other prospective empirical social science research that utilizes public study registries. This framework depicts an integrated system that leverages the capacities of existing infrastructure in the form of public registries, institutional review boards, journals, and granting agencies, as well as investigators themselves, to efficiently incentivize full reporting and thereby, improve confidence in social science findings. In addition to increasing access to the results of scientific endeavors, a well-coordinated research ecosystem can prevent scholars from wasting time investigating the same questions in ways that have not worked in the past and reduce wasted funds on the part of granting agencies.
The infant’s view redefines the problem of referential uncertainty in early word learning
Authors: Yu Chen , Zhang Yayun , Slone Lauren K. , Smith Linda B.
Published: December 2021

Significance

Human infants learn object names by mapping heard names to perceived things. The key challenge to this learning is referential uncertainty: For any heard name, there are many candidate referents with variable perceptual properties. Previous experimental research on how infants solve this problem has been based on different assumptions about the nature of this uncertainty. The present study quantifies the degrees of referential uncertainty by measuring infants’ real-time attention to the potential referents when parents name unfamiliar objects. We discovered an unexpected bimodal distribution of infant attention to the intended referents in parent speech during everyday parent–infant interactions, which redefines the century-long puzzle of referential uncertainty as a problem in the sampling of data for learning.
On the mechanism of tissue-specific mRNA delivery by selective organ targeting nanoparticles
Authors: Dilliard Sean A. , Cheng Qiang , Siegwart Daniel J.
Published: December 2021

Significance

Liver accumulation represents a significant barrier in the development of therapeutically efficacious nanoparticle drug delivery systems. Using a series of lipid nanoparticles with distinct organ-targeting properties, we provide evidence for a plausible mechanism of action for nanoparticle delivery to non-liver tissues. Following intravenous injection, specific proteins in the blood are recruited to the nanoparticle’s surface based on its molecular composition and they endow it with a unique biological identity that governs its ultimate fate in the body. An innovative paradigm emerges from this mechanistic understanding of nanoparticle delivery—endogenous targeting—wherein the molecular composition of a nanoparticle is rationally engineered to interact with specific proteins in the blood to overcome liver accumulation and to target specific organs.
Elastic forces drive nonequilibrium pattern formation in a model of nanocrystal ion exchange
Authors: Frechette Layne B. , Dellago Christoph , Geissler Phillip L.
Published: December 2021

Significance

The widely used process of nanocrystal ion exchange operates out of thermodynamic equilibrium and can require mixing components of varying sizes. Here we use theory and computer simulation to study a simple model which captures these two basic features of ion exchange reactions. We show that a strong driving force for exchange among different-sized species creates nonequilibrium patterns within model nanocrystals. We further demonstrate that such patterns can be thermodynamically stable within core/shell nanocrystals. These results help us understand the heterostructures formed in ion-exchanged nanocrystals and suggest strategies for leveraging elasticity to design patterns in nanoscale materials.
A world of two agendas
Authors: Minooie Milad
Published: December 2021

This article studies the efficiency of different samples for content analysis of news in media effects studies by comparing the agenda-setting effect of a classic sample with the effect of a sample drawn based on audiences’ self-reported media habits. Contrary to the belief that exposure to sampled media content is necessary for observation of media effects, samples drawn based on overall readership/viewership of the media are more efficient than samples based on audiences’ actual consumption habits. A traditional media sample yields a stronger agenda-setting effect compared to a sample drawn based on self-reported media habits. But correlations between the two media samples are also strong. The findings suggest that a broad intermedia agenda-setting process makes it possible for researchers to draw a traditional sample that is representative of the issues salient to audiences regardless of their level of exposure to the sampled media. In other words, even in a demassified media environment, traditional samples are still the best option for media effects researchers.
As if irony was in stock
Authors: Lehmann Claudia , Bergs Alexander
Published: December 2021

The linguistic treatment of verbal irony1has more often than not focused on novel, ad hoc ironies. Research in the last decade, however, suggests that there is a considerable number of utterances that are either schematic or lexically filled and interpreted as ironic by convention. By analyzing three of these, i.e.Tell me about it, XP pro BE not(A Michelangelo he is not) and stand-alone insubordinateas if(As if anyone could pronounce that), the present paper will show that these expressions are best analyzed as constructions (Goldberg 1995,2006). The paper will further show that the Viewpoint account of irony (Dancygier 2017;Tobin & Israel 2012) describes the data at hand most adequately.
Direct measurement of electron Bernstein waves in Low Aspect ratio Torus Experiment (LATE)
Authors: Guo Xingyu , Ashida Ryo , Noguchi Yuto , Kajita Ryusuke , Tanaka Hitoshi , Uchida Masaki , Maekawa Takashi
Published: December 2021

By using a newly developed five-pin probe antenna and two-dimensional mechanical probe driving system, the 2D wave pattern of phase and amplitude has been directly measured in the Low Aspect ratio Torus Experiment (LATE) device, for an overdense ECR plasma with microwave obliquely injected. In the case of O-mode injection, an electron Bernstein wave (EBW)-like wave pattern has been detected for the first time, in a localized region near the upper hybrid resonance layer. The pattern has a short wavelength of about 2 mm and is also electrostatic and backward. In the case of X-mode injection, the 2D wave pattern is quite different and no EBW signal can be observed. By adjusting the toroidal magnetic field in O-mode injection, it is found that both the position and size of the EBW region have changed, which suggests the localized condition of efficient O-X-B conversion and high collisional damping rate of EBWs in these experiments.
Preparation and performance of graphene oxide/self-healing microcapsule composite mortar
Authors: Tang Liang , Cheng Zhihe , Ling Xianzhang , Cong Shengyi , Nan Jiaming
Published: December 2021

In order to solve the special needs for the durability and resistance of concrete materials in power transmission projects in Northwest China. Using sodium silicate and bentonite as capsule core and ethyl cellulose as capsule wall, microcapsules were synthesized by physical method. Standard specimens of cement-based materials were prepared by adding graphene oxide as conductive medium. Indoor experiments and micro technology were used to determine the optimal ratio of graphene-microcapsules, study the effects of graphene content, microcapsule content, and curing age on compressive strength, resistance, and self-repairing effect of the composite material. The results show that the average size of microcapsules was about 1.25 mm. The microcapsule was a relatively regular sphere with rough surface and dense structure. The recommended content was 2% microcapsules and 0.1% graphene oxide. With the increase of microcapsules and graphene oxide, the compressive strength first increased and then decreased, and the resistance increased gradually. After the cracks were repaired, the repairing rate of compressive strength was 57% and the recovery rate was 81%.
Trapping a magnetic field of 17.89 T in stacked coated conductors by suppression of flux jumps
Authors: Suyama Masahiro , Pyon Sunseng , Iijima Yasuhiro , Awaji Satoshi , Tamegai Tsuyoshi
Published: December 2021

We have successfully trapped a field of 17.89 T at 6.5 K at the center of a compact coated-conductor (CC) stacks (13

×

12

×

11.7 mm3) within 75 min by suppressing flux jumps. The CC stack consists of 200 sheets of EuBa2Cu3O7 CCs with BaHfO3 nanorods to increase the critical current density at high fields and low temperatures. To enhance thermomagnetic stability, the central 50 CCs are coated with 1 µm thick Pb with large specific heat at low temperatures. Numerical calculations based on the actual J
c–H characteristics reproduces the trapped field quantitatively. New directions for achieving even higher trapped field at higher temperatures and making use of the trapped field are discussed.
Predictive 3D modelling of erosion and deposition in ITER with ERO2.0: from beryllium main wall, tungsten divertor to full-tungsten device
Authors: Eksaeva A , Kirschner A , Romazanov J , Brezinsek S , Linsmeier Ch , Maviglia F , Siccinio M , Ciattaglia S
Published: December 2021

Erosion and deposition is modelled with ERO2.0 for a hypothetical full-tungsten ITER for an ELM-free H-Mode baseline deuterium discharge. A parameter study considering seeding impurities (Ne, Ar, Kr, Xe) at constant percentages (0.05% to 1.0%) of the deuterium ion flux is done while neglecting their radiation cooling and core plasma compatibility. With pure deuterium plasma, tungsten main wall erosion is only due to charge exchange deuterium atoms and self-sputtering and there is only minor tungsten divertor sputtering. With a beryllium main wall, beryllium erosion is due to deuterium ions, charge exchange deuterium neutrals and self-sputtering. For this case, tungsten in the divertor is eroded by beryllium ions and self-sputtering. The simulations for full-tungsten device including seeded impurities leads to significant tungsten erosion in the divertor. In general, tungsten erosion, self-sputtering and deposition increase by factors larger than 50 at the main wall and 5000 in the divertor compared to pure deuterium plasma.
Shift-symmetric 𝖲𝖮(𝖭) multi-Galileon
Authors: Aoki Katsuki , Manita Yusuke , Mukohyama Shinji
Published: December 2021

A Poincarè invariant, local scalar field theory in which the Lagrangian and the equation of motion contain only up to second-order derivatives of the fields is called generalized Galileon. The covariant version of it in four dimensions is called Horndeski theory, and has been vigorously studied in applications to inflation and dark energy. In this paper, we study a class of multi-field extensions of the generalized Galileon theory. By imposing shift and SO(N) symmetries on all the currently known multi-Galileon terms in general dimensions, we find that the structure of the Lagrangian is uniquely determined and parameterized by a series of coupling constants. We also study tensor perturbation in the shift-symmetric SO(3) multi-Galileon theory in four dimensions. The tensor perturbations can obtain a mass term stemming from the same symmetry breaking pattern as the solid inflation. We also find that the shift-symmetric SO(3) multi-Galileon theory gives rise to new cubic interactions of the tensor modes, suggesting the existence of a new type of tensor primordial non-Gaussianity.
An integrated analytical model for the forecasting of the molten pool dimensions in Selective Laser Melting
Authors: Angelastro Andrea , Campanelli Sabina Luisa
Published: December 2021

Selective laser melting (SLM) is one of the most promising processes in the Additive Manufacturing of metals because of the possibility to fabricate complex geometry parts with a wide range of materials. The molten pool dimensions are notoriously crucial for the production of high quality parts, in terms of mechanical properties and roughness, and to control the ‘balling’ phenomenon. In the past, several studies have been conducted to monitor temperature gradient and thermal history, stress and deformation field, balling occurrence, effect of volume shrinkage and the effect of process parameters on temperature evolution. Up to now, very few works are available in literature on the effects of the process parameters on the molten pool shape and dimensions: moreover, they also neglect the simultaneously effect of various physical factors. In this work, an integrated analytical model, consisting of three sub-models (thermal, optical and melting sub-models), with the purpose to forecast the molten pool dimensions in terms of width and depth, was developed. An experimental plan has been carried out, processing the 18 maraging 300 steel, to demonstrate the capability and the accuracy of the presented model. The obtained results demonstrate that the integrated analytical model led to optimal forecasting.
Persistent and enhanced spin-nematic squeezing in a spinor Bose–Einstein condensate
Authors: Li Xinfang , Liu Jianning , Seth Osei , Xiong Heng-Na , Tan Qing-Shou , Huang Yixiao
Published: December 2021

We propose a simple scheme to realize the persistent spin-nematic squeezing in a spinor Bose–Einstein condensate by rapidly turning-off the external magnetic field at a time that maximal spin-nematic squeezing occurs. We observe that the optimal spin-nematic squeezing can be maintained in a nearly fixed direction. For a proper initial magnetic field, the optimal squeezing can be obviously enhanced. We further construct a spin-mixing interferometer, where the quantum correlation of the squeezed state (generated by our scheme) is fully utilized in the phase measurement, and show the phase sensitivity of the interferometer has a significant enhancement.
Predictive modeling to determine oxygen and ozone doses applicable to in situ remediation of polluted water bodies
Authors: Tabla-Hernandez Jacobo , Dellepere Alejandro V , Mangas-Ramírez Ernesto
Published: December 2021

This work shows the results for the first time of calibrating and validating a mathematical model, capable of predicting the amounts of O3 and O2 necessary to reduce pollution levels in a lake based on the chemical oxygen demand (COD), biochemical oxygen demand (BOD5), total nitrogen (TN), total phosphorus (TP) and fecal coliforms (FC) concentrations. The model was designed to treat a natural or artificial lake as though it were an aerated lagoon operating as an idealized continuous flow complete-mix reactor. The O3 yield constant for eliminating the non-biodegradable fraction of COD and for deactivating fecal coliforms were laboratory derived and calibrated with field values. Based on the field parameters, the model accurately predicted a reduction in BOD5, COD, TN, TP and FC of 53%, 51%, 39%, 42% and 98%, respectively. The model proved to be effective in predicting O2 and O3 demand and time of recovery of a polluted water body.
Thermalization of small quantum systems: from the zeroth law of thermodynamics
Authors: Wang Jiaozi , Wang Wen-ge , Wang Jiao
Published: December 2021

Thermalization of isolated quantum systems has been studied intensively in recent years and significant progresses have been achieved. Here, we study thermalization of small quantum systems that interact with large chaotic environments under the consideration of Schrödinger evolution of composite systems, from the perspective of the zeroth law of thermodynamics. Namely, we consider a small quantum system that is brought into contact with a large environmental system; after they have relaxed, they are separated and their temperatures are studied. Our question is under what conditions the small system may have a detectable temperature that is identical with the environmental temperature. This should be a necessary condition for the small quantum system to be thermalized and to have a well-defined temperature. By using a two-level probe quantum system that plays the role of a thermometer, we find that the zeroth law is applicable to quantum chaotic systems, but not to integrable systems.
An electroceutical approach enhances myelination via upregulation of lipid biosynthesis in the dorsal root ganglion
Authors: Intisar Aseer , Kim Woon-Hae , Shin Hyun Young , Kim Min Young , Kim Yu Seon , Lim Heejin , Kang Hyun Gyu , Mo Yun Jeoung , Aly Mohamed Aly Saad , Lee Yun-Il , Kim Minseok S
Published: December 2021

As the myelin sheath is crucial for neuronal saltatory conduction, loss of myelin in the peripheral nervous system (PNS) leads to demyelinating neuropathies causing muscular atrophy, numbness, foot deformities and paralysis. Unfortunately, few interventions are available for such neuropathies, because previous pharmaceuticals have shown severe side effects and failed in clinical trials. Therefore, exploring new strategies to enhance PNS myelination is critical to provide solution for such intractable diseases. This study aimed to investigate the effectiveness of electrical stimulation (ES) to enhance myelination in the mouse dorsal root ganglion (DRG)—an ex vivo model of the PNS. Mouse embryonic DRGs were extracted at E13 and seeded onto Matrigel-coated surfaces. After sufficient growth and differentiation, screening was carried out by applying ES in the 1–100 Hz range at the beginning of the myelination process. DRG myelination was evaluated via immunostaining at the intermediate (19 days in vitro (DIV)) and mature (30 DIV) stages. Further biochemical analyses were carried out by utilizing ribonucleic acid sequencing, quantitative polymerase chain reaction and biochemical assays at both intermediate and mature myelination stages. Imaging of DRG myelin lipids was carried out via time-of-flight secondary ion mass spectrometry (ToF-SIMS). With screening ES conditions, optimal condition was identified at 20 Hz, which enhanced the percentage of myelinated neurons and average myelin length not only at intermediate (129% and 61%) but also at mature (72% and 17%) myelination stages. Further biochemical analyses elucidated that ES promoted lipid biosynthesis in the DRG. ToF-SIMS imaging showed higher abundance of the structural lipids, cholesterol and sphingomyelin, in the myelin membrane. Therefore, promotion of lipid biosynthesis and higher abundance of myelin lipids led to ES-mediated myelination enhancement. Given that myelin lipid deficiency is culpable for most demyelinating PNS neuropathies, the results might pave a new way to treat such diseases via electroceuticals.
Shape and scaling of the mean-velocity profile in thermally-stratified plane-Couette flows
Authors: Zhang Dongrong
Published: December 2021

It has long been known from measurements that buoyant motions cause the mean-velocity profile (MVP) in thermally-stratified, wall-bounded turbulent flows to significantly deviate from its constant-density counterpart. Theoretical analysis has restricted attention to an ‘intermediate layer’ of the MVP, akin to the celebrated ‘log layer’ in the constant-density case. Here, for thermally-stratified plane-Couette flows, we study the shape and scaling of the whole MVP. We elucidate the mechanisms that dictate the shape of the MVP by using the framework of the spectral link (Gioia et al 2010 Phys. Rev. Lett.
105 184501), and obtain scaling laws for the whole MVP by generalizing the Monin-Obukhov similarity theory.
The Role of Board Leadership Structure in Firm Governance
Authors: Bement Danuse , Krause Ryan
Published: December 2021

Boards of directors are governing bodies that reside at the apex of the modern corporation. Boards monitor the behavior of firm management, provide managers access to knowledge, expertise, and external networks, and serve as advisors and sounding boards for the CEO. Board attributes such as board size and independence, director demographics, and firm ownership have all been studied as antecedents of effective board functioning and, ultimately, firm performance. Steady progress has been made toward understanding how boards influence firm outcomes, but several key questions about board leadership structure remain unresolved.

Research on board leadership structure encompasses the study of board chairs, lead independent directors, and board committees. Board chair research indicates that when held by competent individuals, this key leadership position has the potential to contribute to efficient board functioning and firm performance. Researchers have found conflicting evidence regarding CEO duality, the practice of the CEO also serving as the board chair. The effect of this phenomenon—once ubiquitous among U.S. boards—ranges widely based on circumstances such as board independence, CEO power, and/or environmental conditions. Progressively, however, potential negative consequences of CEO duality proposed by agency theory appear to be counterbalanced by other governance mechanisms and regulatory changes.

A popular mechanism for a compromise between the benefits of CEO duality and independent monitoring is to establish the role of a lead independent director. Although research on this role is in its early stage, results suggest that when implemented properly, the lead independent director can aid board monitoring without adding confusion to a unified chain of command. Board oversight committees, another key board leadership mechanism, improve directors’ access to information, enhance decision-making quality by allowing directors to focus on specialized topics outside of board meetings, and increase the speed of response to critical matters. Future research on the governance roles of boards, leadership configurations, and board committees is likely to explore theories beyond agency and resource dependence, as well as rely less on collecting archival data and more on finding creative ways to access rarely examined board interactions, such as board and committee meetings and executive sessions.
Risk in Strategic Management
Authors: Puia George M. , Potts Mark D.
Published: December 2021

Although risk is an essential element of the business landscape and one of the more widely researched topics in business, there is noticeably less scholarship on strategic risk. Business risk literature tends to only delineate characteristics of risk that are operational rather than strategic in nature. The current operational risk paradigm focuses primarily on only two dimensions of risk: the probability of its occurrence and the severity of its outcomes. In contrast, literature in the natural and social sciences exhibits greater dimensionality in the risk lexicon, including temporal risk dimensions absent from academic business discussions. Additionally, descriptions of operational risk included minimal linkage to strategic outcomes that could constrain or enable resources, markets, or competition.

When working with a multidimensional model of risk, one can adjust the process of environmental scanning and risk assessment in ways that were potentially more measurable. Given the temporal dimensions of risk, risk management cannot always function proactively. In risk environments with short risk horizons, rapid risk acceleration, or limited risk reaction time, firms must utilize dynamic capabilities.

The literature proposes multiple approaches to managing risk that are often focused on single challenges or solutions. By combining a strategic management focus with a multidimensional model of strategic risk, one can match risk management protocols to specific strategic challenges. Lastly, one of more powerful dimensions of risky events is their ability to differentially affect competitors, changing the basis of competition. Risk need not solely be viewed as defending against potential losses; many risky occurrences may represent new strategic opportunities.
Expert Networking and International Governance: Questions of Democracy
Authors: Eriksen Andreas
Published: December 2021

Networks of experts coordinated or orchestrated by international bodies have become so widespread and influential that they are said to shape a new world order. Standards for consumer safety, investor protection, and environmental sustainability are governed by appeals to the epistemic authority of experts. Typically, formal international organizations orchestrate cross-border constellations of public–private collaborations between groups that are deemed to have relevant knowledge. This trend is part of a depoliticization of decision-making; policy issues are framed as technical problems that should be kept at a distance from party politics. The question here is how to conceptualize and assess this development in democratic terms.

In political theory, three kinds of approach have evolved in response to this trend. At one extreme, the argument is that governance beyond the state cannot be legitimate until it has implemented modes of representation and contestation familiar from the domestic context. At the other extreme, the argument is that legitimacy beyond the state should be decoupled from democratic concerns and be legitimated on technocratic grounds. Between these two poles is the argument that democracy does not have to resemble the domestic model in organizational terms and can fruitfully be reconceived or reinterpreted in the international context. Versions of the reinterpretive approach are currently popular under different theoretical labels. It is fruitful to use it as a model for considering questions of democratic legitimacy for the expert networks that constitute or interact with international organizations.

In following the reinterpretive route, a natural starting point is to consider what the key evaluative dimensions of democracy are. At an abstract level, democracy is about three main considerations:

1. Authorization: The people are the rightful principals of public action. It is necessary to consider how people can be empowered to challenge and potentially veto opinions that flow from expert networks.

2. Attitude: Democratically justified institutions express the right kind of concern for people as equals. There are important questions about how the technical rationalities of expert networks can show consideration for a reasonable pluralism of perspectives and how “soft law” can address subjects with appropriate respect for citizens’ claim to justification and rule of law.

3. Area: The authority of democratically legitimate institutions must be matched by a defined sphere of answerability. For the area of expert networks, this issue concerns both the scope of expert mandates and whether there is a fit between mandate and actual practice.

The task for an assessment of the democratic legitimacy of expert networks is to consider more fully what each of these evaluative dimensions imply in the relevant context.
Difference, Intersectionality, and Organizing
Authors: McDonald Jamie
Published: December 2021

In organizational scholarship, difference is broadly conceptualized as the ways in which individuals differ from each other along the lines of socially significant identities and characteristics. As such, difference encompasses social identities related to gender, race, class, sexuality, ability, and national origin. In addition to social identities, difference also encompasses individual characteristics, such as education level, family type, and health conditions. Organizational scholarship increasingly considers difference to be a constitutive feature of organizing. As such, difference is not merely one aspect of organizing that is only relevant in some circumstances, but a defining feature of organizing processes to which it is always important to attend because dominant discourses and value systems privilege certain differences over others. Central to difference scholarship is the concept of intersectionality, which holds that various identities intersect with each other to shape social and organizational experiences in ways that are intertwined with privilege and/or disadvantage. Scholarship on difference, intersectionality, and organizing has drawn from multiple critical theoretical frameworks, such as critical race theory, standpoint feminism, postmodern feminism, queer theory, and postcolonial theory. A growing amount of scholarship on difference, intersectionality, and organizing is also empirical and sheds light on how overlapping, intersectional identities matter in organizational settings and how they are embedded in power relations.
The Regulation of Sleep
Authors: Heller Craig
Published: December 2021

The words “regulation” and “control” have different meanings. A rich literature exists on the control mechanisms of sleep—the genomic, molecular, cellular, and circuit processes responsible for arousal state changes and characteristics. The regulation of sleep refers to functions and homeostatic maintenance of those functions. Much less is known about sleep regulation than sleep control, largely because functions of sleep are still unknown. Regulation requires information about the regulated variable that can be used as feedback information to achieve optimal levels. The circadian timing of sleep is regulated, and the feedback information is entraining stimuli such as the light–dark cycle. Sleep itself is homeostatically regulated, as evidenced by sleep deprivation experiments. Eletroenceophalography (EEG) slow-wave activity (SWA) is regulated, and it appears that adenosine is the major source of feedback information, and that fact indicates an energetic function for sleep. The last aspect of sleep regulation discussed in this short article is the non-rapid eye movement (NREM) and rapid eye movement (REM) sleep cycling. Evidence is discussed that supports the argument that NREM sleep is in a homeostatic relationship with wake, and REM sleep is in a homeostatic relationship with NREM sleep.
Homeschooling in the Educational Landscape of Latin America
Authors: Muniz Ribeiro Barbosa Luciane
Published: December 2021

A number of developments stemmed from reforms to Latin America’s educational landscape beginning in 1990, with the regulamentation of homeschooling differing in countries across this region. Academic research and literature on homeschooling in these countries are just beginning, but it is clear that there is a “normative void” on this topic that is experienced by almost all Latin American countries despite the growing number of families choosing this form of education. There is a need to broaden the debate regarding the regulation of homeschooling in Latin America by analyzing local particularities in view of the commitment to protect the right to education for Latin American children and adolescents.
Commercial Networks Connecting Southeast Asia with the Indian Ocean
Authors: Hoogervorst Tom
Published: December 2021

Southeast Asian history has seen remarkable levels of mobility and durable connections with the rest of the Indian Ocean. The archaeological record points to prehistoric circulations of material culture within the region. Through the power of monsoon sailing, these small-scale circuits coalesced into larger networks by the 5th century bce. Commercial relations with Chinese, Indian, and West Asian traders brought great prosperity to a number of Southeast Asian ports, which were described as places of immense wealth. Professional shipping, facilitated by local watercraft and crews, reveals the indigenous agency behind such long-distance maritime contacts. By the second half of the first millennium ce, ships from the Indo-Malayan world could be found as far west as coastal East Africa. Arabic and Persian merchants started to play a larger role in the Indian Ocean trade by the 8th century, importing spices and aromatic tree resins from sea-oriented polities such as Srivijaya and later Majapahit. From the 15th century, many coastal settlements in Southeast Asia embraced Islam, partly motivated by commercial interests. The arrival of Portuguese, Dutch, and British ships increased the scale of Indian Ocean commerce, including in the domains of capitalist production systems, conquest, slavery, indentured labor, and eventually free trade. During the colonial period, the Indian Ocean was incorporated into a truly global economy. While cultural and intellectual links between Southeast Asia and the wider Indian Ocean have persisted in the 21st century, commercial networks have declined in importance.
Clements Musa Kadalie and the Industrial and Commercial Workers’ Union of Africa
Authors: Dee Henry
Published: December 2021

Between 1919 and 1929, Clements Musa Kadalie rose to worldwide fame as secretary of the Industrial and Commercial Workers’ Union of Africa (ICU). Under his leadership, the ICU transformed Southern Africa’s labor movement. Organizing black railway, dock and factory workers, miners, domestic servants, and farm laborers across South Africa, South West Africa (modern-day Namibia), Basutoland (Lesotho), and Southern Rhodesia (Zimbabwe) into “One Big Union,” the ICU led a number of strikes, challenged pass laws and unionized anywhere between 100,000 and 250,000 members. Over six foot tall and always dressed in an immaculate suit, Kadalie regularly addressed mass meetings of thousands of people across rural and urban South Africa.

Kadalie was born in Chifira, Tongaland, British Central Africa Protectorate (modern-day Malawi) around 1895. After being expelled from the local mission school, he migrated via Southern Rhodesia to South Africa. He was elected as the ICU’s secretary at its first meeting. The ICU took a leading role in the 1919 Cape Town dock strike and won wage increases for dock workers in 1920. By 1925, the trade union had over 50 branches across Southern Africa and a widely circulating newspaper, The Workers’ Herald. In 1927, Kadalie toured Europe, calling on the international labor movement to campaign against a raft of repressive legislation. Amid fractious internal disputes, however, Kadalie’s “czarlike” character, frivolous expenditure and “foreign” birth were publicly denounced by rivals, and the financial contributions of ICU members collapsed. Kadalie led a breakaway Independent ICU from February 1929 and called a general strike in East London in January 1930. He passed away on November 28, 1951, leaving a complicated legacy. The ICU’s radical rhetoric and mass mobilization, nevertheless, demonstrated both the possibility and necessity of organizing black workers and inspired black leaders across the world for decades to come.