Anode-less seawater batteries with a Na-ion conducting solid-polymer electrolyte for power to metal and metal to power energy storage

Seawater batteries (SWBs) have been mostly researched for large scale energy storage and (sub-)marine applications. In a SWB, the aqueous catholyte (seawater) and a non-aqueous anolyte (aprotic solvent solution) are physically separated by a NASICON solid electrolyte membrane. Given the practically unlimited Na+ ion supply from seawater, the energy storage is only limited by the amount of Na stored in the negative electrode. Therefore, the highest volumetric and gravimetric energy densities can be achieved by storing Na metal without the need for a host material. To achieve safe realization of such a cell, a compact, metal-less anode design is herein demonstrated for the first time. The anode compartment integrates the NASICON solid electrolyte, a Na-ion conductive solid-state polymer electrolyte (Na-SPE), having a high ionic conductivity (over 1 mS cm−1 at moderate room temperature), and a negative electrode current collector. The reactive Na metal is not employed in the cell construction, but it is harvested from seawater upon charge (power to metal) and reconverted into energy upon the discharge process (metal to power). The overall round-trip energy efficiency (RTE) of the devices is over 85% at room temperature

Observation of transverse spin Nernst magnetoresistance induced by thermal spin current in ferromagnet/non-magnet bilayers

Electric generation of spin current via spin Hall effect is of great interest as it allows an efficient manipulation of magnetization in spintronic devices. Theoretically, spin current can be also created by a temperature gradient, which is known as spin Nernst effect. Here, we report spin Nernst effect-induced transverse magnetoresistance in ferromagnet (FM)/non-magnetic heavy metal (HM) bilayers. We observe that the magnitude of transverse magnetoresistance (i.e., planar Nernst signal) in FM/HM bilayers is significantly modified by HM and its thickness. This strong dependence of transverse magnetoresistance on HM evidences the spin Nernst effect in HM; the generation of thermally-induced spin current in HM and its subsequent reflection at the FM/HM interface. Our analysis of transverse magnetoresistance shows that the spin Nernst angles of W and Pt have the opposite sign to their spin Hall angles. Moreover, our estimate implies that the magnitude of the spin Nernst angle would be comparable to that of the spin Hall angle, suggesting an efficient generation of spin current by the spin Nernst effect

Treatment of Thoracolumbar Fracture

The most common fractures of the spine are associated with the thoracolumbar junction. The goals of treatment of thoracolumbar fracture are leading to early mobilization and rehabilitation by restoring mechanical stability of fracture and inducing neurologic recovery, thereby enabling patients to return to the workplace. However, it is still debatable about the treatment methods. Neurologic injury should be identified by thorough physical examination for motor and sensory nerve system in order to determine the appropriate treatment. The mechanical stability of fracture also should be evaluated by plain radiographs and computed tomography. In some cases, magnetic resonance imaging is required to evaluate soft tissue injury involving neurologic structure or posterior ligament complex. Based on these physical examinations and imaging studies, fracture stability is evaluated and it is determined whether to use the conservative or operative treatment. The development of instruments have led to more interests on the operative treatment which saves mobile segments without fusion and on instrumentation through minimal invasive approach in recent years. It is still controversial for the use of these treatments because there have not been verified evidences yet. However, the morbidity of patients can be decreased and good clinical and radiologic outcomes can be achieved if the recent operative treatments are used carefully considering the fracture pattern and the injury severity

Side Channel Attacks and Countermeasures on Pairing Based Cryptosystems over Binary Fields

Pairings on elliptic curves have been used as cryptographic primitives for the development of new applications such as identity based schemes. For the practical applications, it is crucial to provide efficient and secure implementations of the pairings. There have been several works on efficient implementations of the pairings. However, the research for secure implementations of the pairings has not been thoroughly investigated. In this paper, we investigate vulnerability of the pairing used in some pairing based protocols against side channel attacks. We propose an efficient algorithm secure against such side channel attacks of the eta pairing using randomized projective coordinate systems for the pairing computation

GAP: Born to Break Hiding

Recently, Machine Learning (ML) is widely investigated in the side-channel analysis (SCA) community. As an artificial neural network can extract the feature without preprocessing, ML-based SCA methods relatively less rely on the attacker\u27s ability. Consequently, they outperform traditional methods. Hiding is a countermeasure against SCA that randomizes the moments of manipulating sensitive data. Since hiding could disturb the neural network\u27s learning, an attacker should design a proper architecture against hiding. In this paper, we propose inherently robust architecture against every kind of desynchronization. We demonstrated the proposed method with plenty of datasets, including open datasets. As a result, our method outperforms state-of-the-art on every dataset

Novel Single-Trace ML Profiling Attacks on NIST 3 Round candidate Dilithium

Dilithium is a lattice-based digital signature, one of the finalist candidates in the NIST\u27s standardization process for post-quantum cryptography. In this paper, we propose a first side-channel attack on the process of signature generation of Dilithium. During the Dilithium signature generation process, we used NTT encryption single-trace for machine learning-based profiling attacks. In addition, it is possible to attack masked Dilithium using sparse multiplication. The proposed method is shown through experiments that all key values can be exposed 100% through a single-trace regardless of the optimization level

The possible roles of hyperpolarization-activated cyclic nucleotide channels in regulating pacemaker activity in colonic interstitial cells of Cajal

BACKGROUND: Hyperpolarization-activated cyclic nucleotide (HCN) channels are pacemaker channels that regulate heart rate and neuronal rhythm in spontaneously active cardiac and neuronal cells. Interstitial cells of Cajal (ICCs) are also spontaneously active pacemaker cells in the gastrointestinal tract. Here, we investigated the existence of HCN channel and its role on pacemaker activity in colonic ICCs. METHODS: We performed whole-cell patch clamp, RT-PCR, and Ca(2+)-imaging in cultured ICCs from mouse mid colon. RESULTS: SQ-22536 and dideoxyadenosine (adenylate cyclase inhibitors) decreased the frequency of pacemaker potentials, whereas both rolipram (cAMP-specific phosphodiesterase inhibitor) and cell-permeable 8-bromo-cAMP increased the frequency of pacemaker potentials. CsCl, ZD7288, zatebradine, clonidine (HCN channel blockers), and genistein (a tyrosine kinase inhibitor) suppressed the pacemaker activity. RT-PCR revealed expression of HCN1 and HCN3 channels in c-kit and Ano1 positive colonic ICCs. In recordings of spontaneous intracellular Ca(2+) [Ca(2+)](i) oscillations, rolipram and 8-bromo-cAMP increased [Ca(2+)](i) oscillations, whereas SQ-22536, CsCl, ZD7288, and genistein decreased [Ca(2+)](i) oscillations. CONCLUSIONS: HCN channels in colonic ICCs are tonically activated by basal cAMP production and participate in regulation of pacemaking activity