Technological Capability Building in the Automotive Industry: Comparing China with South Korea

Why has China developed a huge automotive market without building up autonomous technological capability? While comparing China with South Korea’s experience, we argue that this phenomenon has to be understood in the context of a misleading and ineffective policy regime and a fragmented political structure, which in turn are associated with a disincentive market environment (sizable but unsophisticated demand) and China’s ongoing systemic restructuring that has so far been oriented toward management fragmentation. Keywords: China versus Korea; automotive industry; technological capabilit

Unilateral Auditory Neuropathy Caused by Cochlear Nerve Deficiency

Objective. To explore possible corelationship between the cochlear nerve deficiency (CND) and unilateral auditory neuropathy (AN). Methods. From a database of 85 patients with unilateral profound sensorineural hearing loss, eight who presented with evoked otoacoustic emissions (EOAEs) or cochlear microphonic (CM) in the affected ear were diagnosed with unilateral AN. Audiological and radiological records in eight patients with unilateral AN were retrospectively reviewed. Results. Eight cases were diagnosed as having unilateral AN caused by CND. Seven had type “A” tympanogram with normal EOAE in both ears. The other patient had unilateral type “B” tympanogram and absent OAE but CM recorded, consistent with middle ear effusion in the affected ear. For all the ears involved in the study, auditory brainstem responses (ABRs) were either absent or responded to the maximum output and the neural responses from the cochlea were not revealed when viewed by means of the oblique sagittal MRI on the internal auditory canal. Conclusion. Cochlear nerve deficiency can be seen by electrophysiological evidence and may be a significant cause of unilateral AN. Inclined sagittal MRI of the internal auditory canal is recommended for the diagnosis of this disorder

N-(2-Hy­droxy­eth­yl)-5-(4-meth­oxy­phen­yl)-4H-pyrazole-3-carboxamide

In the title compound, C13H15N3O3, the dihedral angle between the benzene and pyrazole rings is 7.7 (1)° and the O—C—C—N torsion angle of the side chain is 74.1 (2)°. In the crystal, mol­ecules are linked by O—H⋯O, N—H⋯O and N—H⋯N hydrogen bonds

Recipe for single-pair-Weyl-points phonons carrying the same chiral charges

Recently, Wang et al. [Phys. Rev. B, 106, 195129 (2022)] challenged a widely held belief in the field of Weyl physics, demonstrating that single-pair-Weyl-points (SP-WPs) can exist in nonmagnetic spinless systems, contrary to previous assumptions that they could only exist in magnetic systems. Wang et al. observed that the SP-WPs with opposite and even chiral charges (i.e., |C| = 2 or 4) could also exist in nonmagnetic spinless systems. In this Letter, we present a novel finding in which SP-WPs have a partner, namely a charged nodal surface, in nonmagnetic spinless systems. In contrast to previous observations, we show that the SP-WPs can have uneven chiral charges (i.e., |C| = 1). We identify 6 (out of 230) space groups (SGs) that contain such SP-WPs by searching the encyclopedia of emergent particles in three-dimensional crystals. Our finds were confirmed through the phonon spectra of two specific materials Zr3O (with SG 182) and NaPH2NO3 (with SG 173). This discovery broadens the range of materials that can host SP-WPs and applies to other nonmagnetic spinless crystals

Cr3_3X4_4 (X=Se, Te) monolayers as new platform to realize robust spin filter, spin diode and spin valve

Two-dimensional ferromagnetic (FM) half-metals are promising candidates for advanced spintronic devices with small-size and high-capacity. Motivated by recent report on controlling synthesis of FM Cr$_3$Te$_4$ nanosheet, herein, to explore the potential application in spintronics, we designed spintronic devices based on Cr$_3$X$_4$ (X=Se, Te) monolayers and investigated their spin transport properties. We found that Cr$_3$Te$_4$ monolayer based device shows spin filtering and dual spin diode effect when applying bias voltage, while Cr$_3$S$_4$ monolayer is an excellent platform to realize a spin valve. The different transport properties are primarily ascribed to the semiconducting spin channel, which is close to and away from the Fermi level in Cr$_3$Te$_4$ and Cr$_3$Se$_4$ monolayers, respectively. Interestingly, the current in monolayer Cr$_3$Se$_4$ based device also displays a negative differential resistance effect (NDRE) and a high magnetoresistance ratio (up to 2*10$^3$). Moreover, we found thermally induced spin filtering effect and NDRE in Cr$_3$Se$_4$ junction when applying temperature gradient instead of bias voltage. These theoretical findings highlight the potential of Cr$_3$X$_4$ (X=Se, Te) monolayers in spintronic applications and put forward realistic materials to realize nanosale spintronic device

Universal relation with regime transition for sediment transport in fine-grained rivers

Fine-grained sediment (grain size under 2,000 μm) builds floodplains and deltas, and shapes the coastlines where much of humanity lives. However, a universal, physically based predictor of sediment flux for fine-grained rivers remains to be developed. Herein, a comprehensive sediment load database for fine-grained channels, ranging from small experimental flumes to megarivers, is used to find a predictive algorithm. Two distinct transport regimes emerge, separated by a discontinuous transition for median bed grain size within the very fine sand range (81 to 154 μm), whereby sediment flux decreases by up to 100-fold for coarser sand-bedded rivers compared to river with silt and very fine sand beds. Evidence suggests that the discontinuous change in sediment load originates from a transition of transport mode between mixed suspended bed load transport and suspension-dominated transport. Events that alter bed sediment size near the transition may significantly affect fluviocoastal morphology by drastically changing sediment flux, as shown by data from the Yellow River, China, which, over time, transitioned back and forth 3 times between states of high and low transport efficiency in response to anthropic activities

Universal relation with regime transition for sediment transport in fine-grained rivers

Fine-grained sediment (grain size under 2,000 μm) builds floodplains and deltas, and shapes the coastlines where much of humanity lives. However, a universal, physically based predictor of sediment flux for fine-grained rivers remains to be developed. Herein, a comprehensive sediment load database for fine-grained channels, ranging from small experimental flumes to megarivers, is used to find a predictive algorithm. Two distinct transport regimes emerge, separated by a discontinuous transition for median bed grain size within the very fine sand range (81 to 154 μm), whereby sediment flux decreases by up to 100-fold for coarser sand-bedded rivers compared to river with silt and very fine sand beds. Evidence suggests that the discontinuous change in sediment load originates from a transition of transport mode between mixed suspended bed load transport and suspension-dominated transport. Events that alter bed sediment size near the transition may significantly affect fluviocoastal morphology by drastically changing sediment flux, as shown by data from the Yellow River, China, which, over time, transitioned back and forth 3 times between states of high and low transport efficiency in response to anthropic activities