The learning and inference efficiencies of an artificial neural network represented by a cross‐point synaptic memristor array can be achieved using a selector, with high selectivity (Ion/Ioff) and ...sufficient death region, stacked vertically on a synaptic memristor. This can prevent a sneak current in the memristor array. A selector with multiple jar‐shaped conductive Cu filaments in the resistive switching layer is precisely fabricated by designing the Cu ion concentration depth profile of the CuGeSe layer as a filament source, TiN diffusion barrier layer, and Ge3Se7 switching layer. The selector performs super‐linear‐threshold‐switching with a selectivity of > 107, death region of −0.70–0.65 V, holding time of 300 ns, switching speed of 25 ns, and endurance cycle of > 106. In addition, the mechanism of switching is proven by the formation of conductive Cu filaments between the CuGeSe and Ge3Se7 layers under a positive bias on the top Pt electrode and an automatic rupture of the filaments after the holding time. Particularly, a spiking deep neural network using the designed one‐selector‐one‐memory cross‐point array improves the Modified National Institute of Standards and Technology classification accuracy by ≈3.8% by eliminating the sneak current in the cross‐point array during the inference process.
An artificial neural network consisting of a hardware‐based cross‐point synaptic memristor array should employ selectors with two‐terminal electrodes to prevent an undesired sneak current and to improve learning and inference efficiencies. Here, a highly reliable super‐linear‐threshold‐switching selector with multiple jar‐shaped Cu‐filaments in the amorphous Ge3Se7 resistive switching layer by controlling the Cu ion concentration depth profile is developed.
Black melanin inks are prepared to selectively exhibit colors under strong light, inspired by human hair. High absorbance of melanin suppresses multiple scattering, causing resonant Mie scattering ...predominant. Various colors can be developed as the resonant wavelength dictated by nanosphere diameter. Therefore, the melanin inks can be used to encrypt and selectively disclose multicolor patterns for anticounterfeiting applications.
Black melanin inks are prepared to selectively exhibit colors under strong light, inspired by human hair. The high absorbance of melanin suppresses multiple scattering, causing resonant Mie scattering to be predominant. Various colors can be developed as the resonant wavelength dictated by nanosphere diameter. Therefore, the melanin inks can be used to encrypt and selectively disclose multicolor patterns for anticounterfeiting applications.
This study projected the future changes in the climate‐type distribution in South Korea according to the Köppen–Trewartha climate classification (KTCC) under the representative concentration pathway ...(RCP) 4.5/8.5 scenarios and the future change of cultivation area of apple (Malus domestica Borkh.) and mandarin (Citrus unshiu Marc.), which are major fruit crops in South Korea, using five regional climate models with a 12.5 km horizontal resolution. According to KTCC, type temperate (D)s is dominant in most of South Korea during the reference period (1981–2005). On the other hand, it is projected that the area of Type D and Type subtropical (C) will decrease and increase, respectively, towards higher latitudes and elevations in the future under RCP4.5/8.5 scenarios. Accordingly, the cultivation areas of major fruit crops in South Korea are projected to change significantly. The cultivation area of apple (mandarin), which is a major current fruit crop in Type D (C), is projected to be reduced (expanded) as it moves towards higher latitudes and elevations in the future. Apples grown throughout South Korea in the present climate (reference period) are not expected to be cultivated in the late‐21C due to climate change. On the other hand, the cultivation area of mandarins is projected to increase steadily in the future. At present, mandarins are cultivated only in Jeju Island, which is located in the south of the South Korea. However, the cultivation area is expected to increase by 1323% in late‐21C under the RCP8.5 scenario compared to the reference period. Moreover, mandarin cultivation is projected to be possible anywhere in South Korea. Nevertheless, in late‐21C, excessive increases in temperature that exceeds the appropriate temperature for mandarin in Jeju Island and the southern part of South Korea will eventually decrease the cultivation area of mandarins.
Possible and suitable cultivation areas of apple (left two columns) and mandarin (right two columns) from early‐21C to late‐21C under RCP4.5/8.5 scenarios. Grid points with black shading denote the mountainous terrain.
This study provides novel insights into the policy effects of timber legality verification methods, specifically Due-diligence (under the European Union Timber Regulation (EUTR)) and Due-care (under ...the Lacey Act), on coniferous and non-coniferous lumber trade, highlighting their significance in the context of global lumber trade. Timber legality verification plays a pivotal role in the global timber trade. We comprehensively assess the impact of verification methods on coniferous and non-coniferous lumber trade, utilizing two decades of trade data (1997–2017) across approximately 160 countries. We employ the difference-in-differences method based on the gravity model of international trade, utilizing robust export–import data and demographic profiles. Our findings demonstrate that the effect of EUTR on coniferous lumber imports ranged between −0.32% and −0.05%, and that on non-coniferous lumber imports ranged between −0.44% and −0.05%, whereas the effect of the Lacey Act on coniferous lumber imports ranged between −0.93% and −0.09%. Non-coniferous lumber imports remained unaffected. The Voluntary Partnership Agreement (VPA) led to decreased exports to the EU and US. Our findings hold two key implications. First, Due-diligence exhibits more consistent policy effects than Due-care. Second, supporting VPA-participating countries is crucial for facilitating timber trade. These insights inform timber trade policies and sustainable practices.
Li‐O2 batteries are promising next‐generation energy storage systems because of their exceptionally high energy density (≈3500 W h kg−1). However, to achieve stable operation, grand challenges remain ...to be resolved, such as preventing electrolyte decomposition and degradation of carbon, a commonly used air electrode in Li‐O2 batteries. In this work, using in situ differential electrochemical mass spectrometry, it is demonstrated that the application of a ZnO coating on the carbon electrode can effectively suppress side reactions occurring in the Li‐O2 battery. By probing the CO2 evolution during charging of 13C‐labeled air electrodes, the major sources of parasitic reactions are precisely identified, which further reveals that the ZnO coating retards the degradation of both the carbon electrode and electrolyte. The successful suppression of the degradation results in a higher oxygen efficiency, leading to enhanced stability for more than 100 cycles. Nevertheless, the degradation of the carbon electrode is not completely prevented by the coating, because the Li2O2 discharge product gradually grows at the interface between the ZnO and carbon, which eventually results in detachment of the ZnO particles from the electrode and subsequent deterioration of the performance. This finding implies that surface protection of the carbon electrode is a viable option to enhance the stability of Li‐O2 batteries; however, fundamental studies on the growth mechanism of the discharge product on the carbon surface are required along with more effective coating strategies.
The effect of the atomic layer deposition coating on the stability of the carbon cathode and electrolyte in Li‐O2 batteries is studied using isotope 13C carbon to distinguish side reactions from the electrolyte decomposition and carbon degradation. Degradation kinetics of both the air electrode and electrolyte during cycles can be significantly retarded by shielding defect sites of carbon cathode, which result in enhanced cycle stability.
Analytical models of low-frequency noise (LFN) characteristics for planar-type tunnel field-effect-transistors (TFETs) are proposed. A surface-potential-based current-voltage model is developed to ...physically represent the current fluctuation due to charge trapping/detrapping in the gate dielectric. An LFN model can be analytically derived from the current fluctuation with a reasonable approximation. The proposed model is verified using Technology Computer Aided Design (TCAD) and measurement data, which are in good agreement with each other. The analytical model can not only serve as a valuable reference and tool for low-power analog circuit design but also provide physical insights into the LFN of TFETs.
Macroautophagy mediates the selective degradation of proteins and non-proteinaceous cellular constituents. Here, we show that the N-end rule pathway modulates macroautophagy. In this mechanism, the ...autophagic adapter p62/SQSTM1/Sequestosome-1 is an N-recognin that binds type-1 and type-2 N-terminal degrons (N-degrons), including arginine (Nt-Arg). Both types of N-degrons bind its ZZ domain. By employing three-dimensional modeling, we developed synthetic ligands to p62 ZZ domain. The binding of Nt-Arg and synthetic ligands to ZZ domain facilitates disulfide bond-linked aggregation of p62 and p62 interaction with LC3, leading to the delivery of p62 and its cargoes to the autophagosome. Upon binding to its ligand, p62 acts as a modulator of macroautophagy, inducing autophagosome biogenesis. Through these dual functions, cells can activate p62 and induce selective autophagy upon the accumulation of autophagic cargoes. We also propose that p62 mediates the crosstalk between the ubiquitin-proteasome system and autophagy through its binding Nt-Arg and other N-degrons.Soluble misfolded proteins that fail to be degraded by the ubiquitin proteasome system (UPS) are redirected to autophagy via specific adaptors, such as p62. Here the authors show that p62 recognises N-degrons in these proteins, acting as a N-recognin from the proteolytic N-end rule pathway, and targets these cargos to autophagosomal degradation.
Rice production in the Korean Peninsula (KP) in the near future (2021–2050) is analysed in terms of the climatic yield potential (CYP) index for Japonica‐type rice. Data obtained from the dynamically ...downscaled daily temperature and sunshine duration for the Historical period (1981–2010) and near future under two Representative Concentration Pathway (RCP4.5 and RCP8.5) scenarios are utilized. To reduce uncertainties that might be induced by using a Coupled General Circulation Model (CGCM)—a Regional Climate Model (RCM) chain in dynamical downscaling, two CGCM—three RCM chains are used to estimate the CYP index. The results show that the mean rice production decreases, mainly due to the increase of the temperature during the grain‐filling period (40 days after the heading date). According to multi model ensemble, the optimum heading date in the near future will be approximately 12 days later and the maximum CYP will be even higher than in the Historical. This implies that the rice production is projected to decrease if the heading date is selected based on the optimum heading date of Historical, but to increase if based on that of near future. The mean rice production during the period of ripening is projected to decrease (to about 95% (RCP4.5) and 93% (RCP8.5) of the Historical) in the western and southern regions of the KP, but to increase (to about 104% (RCP4.5) and 106% (RCP8.5) of the Historical) in the northeastern coastal regions of the KP. However, if the optimum heading date is selected in the near future climate, the peak rice production is projected to increase (to about 105% (RCP4.5) and 104% (RCP8.5) of the Historical) in the western, southern and northeastern coastal regions of the KP, but to decrease (to about 98% (RCP4.5) and 96% (RCP8.5) of the Historical) in the southeastern coastal regions of the KP.
Peak rice production is projected to increase (to about 105% (RCP4.5) and 104% (RCP8.5) of the Historical; red colour) in the western, southern and northeastern coastal regions of the Korean Peninsula, but to decrease (to about 98% (RCP4.5) and 96% (RCP8. 5) of the Historical; blue colour) in the southeastern coastal regions of the Korean Peninsula, if the optimum heading date is selected approximately 12 days later than the Historical period in the near future.
Stress-induced depression and anxiety (DA) are closely connected to gastrointestinal inflammation and dysbiosis, which can suppress brain-derived neurotrophic factor (BDNF) in the brain. Herein, we ...isolated the BDNF expression-inducing probiotics
HY2782 and
HY8002 in lipopolysaccharide-stimulated SH-SY5Y cells. Then, we investigated the effects of HY2782, HY8002, anti-inflammatory L-theanine, and their supplement (PfS, probiotics-fermented L-theanine-containing supplement) on DA in mice exposed to restraint stress (RS) or the fecal microbiota of patients with inflammatory bowel disease and depression (FMd). Oral administration of HY2782, HY8002, or L-theanine alleviated RS-induced DA-like behaviors. They also decreased RS-induced hippocampal interleukin (IL)-1β and IL-6 levels, as well as NF-κB-positive cell numbers, blood corticosterone level, and colonic IL-1β and IL-6 levels and NF-κB-positive cell numbers. L-theanine more potently suppressed DA-like behaviors and inflammation-related marker levels than probiotics. However, these probiotics more potently increased RS-suppressed hippocampal BDNF level and BDNF
NeuN
cell numbers than L-theanine. Furthermore, HY2782 and HY8002 suppressed RS-increased
and
populations in gut microbiota. In particular, they increased
and
populations, which are closely positively associated with hippocampal BDNF expression, and suppressed
,
,
, and
populations, which are closely positively associated with hippocampal IL-1β expression. HY2782 and HY8002 potently alleviated FMd-induced DA-like behaviors and increased FMd-suppressed BDNF, serotonin levels, and BDNF-positive neuronal cell numbers in the brain. They alleviated blood corticosterone level and colonic IL-1β α and IL-6 levels. However, L-theanine weakly, but not significantly, alleviated FMd-induced DA-like behaviors and gut inflammation. BDNF expression-inducing probiotic (HY2782, HY8002,
, and
)-fermented and anti-inflammatory L-theanine-containing supplement PfS alleviated DA-like behaviors, inflammation-related biomarker levels, and gut dysbiosis more than probiotics or L-theanine. Based on these findings, a combination of BDNF expression-inducing probiotics with anti-inflammatory L-theanine may additively or synergistically alleviate DA and gut dysbiosis by regulating gut microbiota-mediated inflammation and BDNF expression, thereby being beneficial for DA.
Recently, "hidden hearing loss" with cochlear synaptopathy has been suggested as a potential pathophysiology of tinnitus in individuals with a normal hearing threshold. Several studies have ...demonstrated that subjects with tinnitus and normal audiograms show significantly reduced auditory brainstem response (ABR) wave I amplitudes compared with control subjects, but normal wave V amplitudes, suggesting increased central auditory gain. We aimed to reconfirm the "hidden hearing loss" theory through a within-subject comparison of wave I and wave V amplitudes and uncomfortable loudness level (UCL), which might be decreased with increased central gain, in tinnitus ears (TEs) and non-tinnitus ears (NTEs).
Human subjects included 43 unilateral tinnitus patients (19 males, 24 females) with normal and symmetric hearing thresholds and 18 control subjects with normal audiograms. The amplitudes of wave I and V from the peak to the following trough were measured twice at 90 dB nHL and we separately assessed UCLs at 500 Hz and 3000 Hz pure tones in each TE and NTE.
The within-subject comparison between TEs and NTEs showed no significant differences in wave I and wave V amplitude, or wave V/I ratio in both the male and female groups. Individual data revealed increased V/I amplitude ratios > mean + 2 SD in 3 TEs, but not in any control ears. We found no significant differences in UCL at 500 Hz or 3000 Hz between the TEs and NTEs, but the UCLs of both TEs and NTEs were lower than those of the control ears.
Our ABR data do not represent meaningful evidence supporting the hypothesis of cochlear synaptopathy with increased central gain in tinnitus subjects with normal audiograms. However, reduced sound level tolerance in both TEs and NTEs might reflect increased central gain consequent on hidden synaptopathy that was subsequently balanced between the ears by lateral olivocochlear efferents.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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