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By introducing a thin non-stoichiometric CeO2-x switching layer between the high oxygen affinity metal TaN top electrode and the TiO2 layer in a TaN/CeO2-x/TiO2/Pt bilayer (BL) device, it is possible to enhance the endurance characteristics and overcome the reliability issue. Compared with a single layer device, a BL device significantly enhances the number of direct current overswitching cycles to >1.2 × 104, non-destructive retention (>104 s), and switching uniformity. A TaON interface layer is formed which served as a reservoir of oxygen ions (O2−) in the SET-process and acts as an O2− supplier to refill the oxygen vacancies in the RESET-process and so plays a key role in the formation and rupture of conductive filaments. This study demonstrates that simply introducing a thin non-stoichiometric CeO2-x switching layer into TiO2-based devices can facilitate the enhancement of the endurance property for future nonvolatile memory applications. [ABSTRACT FROM AUTHOR]

In this letter, we report the coexistence of unipolar and bipolar switching in a solution-based nanocrystalline spinel ferrite ZnFe2O4 thin film prepared by the sol-gel method. It is seen that the Au/ZnFe2O4/Pt device could be activated between unipolar and bipolar switching modes just by choosing RESET-voltage polarity. Conversions between unipolar to bipolar switching modes are reversible and controllable. The results show that the SET-voltage of unipolar switching is smaller than that of bipolar switching, while memory windows (ON/OFF ratio) are identical. Furthermore, filaments are induced by the migration of oxygen vacancies (VOs), which are responsible for reducing variations in SET voltages of unipolar switching. By analyzing the current transport conduction mechanism, the electrode-limited Schottky emission mechanism is dominated in the high field region. Temperature dependence of low and high resistance states indicates that conductive filaments are composed of VOs and metallic Zn atoms, involving Joule heating and electrochemical redox reaction effects. Investigation on coexisting both unipolar and bipolar switching modes in a single Au/ZnFe2O4/Pt memory cell would open a pathway for spinel ferrite based low-cost nonvolatile memory. [ABSTRACT FROM AUTHOR]

The subcellular localization of vitamin E in the membranes of single, isolated neurons from a widely studied neurobiological model, Aplysia californica is studied using time-of-flight secondary ion mass spectrometry (ToF-SIMS). The concentration of vitamin E in the junction region between the cell soma and the low levels in the neurite itself is a new finding that is consistent with several reported roles of the molecule.

The influence of deuterium sintering on improving the reliability of complementary metal oxide semiconductor transistors with nitride sidewall spacers is studied. Comparison of electrical measurements and SIMS depth profiles suggest that the lifetime improvement of wafers with deuterium sintering at the Metal-1 and Metal-4 steps is directly related to the amount of deuterium present at the oxide/silicon interface.

Drawing on various studies, we provide a holistic view incorporating different nested cultural contexts, organizational shame, and health outcomes. We introduce the concept of organizational shame and explain its two key domains: conformity and status/competition. Then, we comprehensively review prior studies on cultural approaches to shame and propose our cultural variance model of organizational shame. Our model illustrates an equilibrium, exhibiting dominant and stable patterns of shame domains formed by reinforcing relationships among three key nested contextual layers: individuals (workers), organizations (firms), and the labor market. We apply our model to discuss general and occupational implications and outline future research directions. Thus, we hope to conceptualize organizational shame within the dynamic contexts of organizations and cultures. [ABSTRACT FROM AUTHOR]

Memory devices with bilayer CeO2−x/ZnO and ZnO/CeO2−x heterostructures sandwiched between Ti top and Pt bottom electrodes were fabricated by RF-magnetron sputtering at room temperature. N-type semiconductor materials were used in both device heterostructures, but interestingly, change in heterostructure and electroforming polarity caused significant variations in resistive switching (RS) properties. Results have revealed that the electroforming polarity has great influence on both CeO2−x/ZnO and ZnO/CeO2−x heterostructure performance such as electroforming voltage, good switching cycle-to-cycle endurance (~ 102), and ON/OFF ratio. A device with CeO2−x/ZnO heterostructure reveals good RS performance due to the formation of Schottky barrier at top and bottom interfaces. Dominant conduction mechanism of high resistance state (HRS) was Schottky emission in high field region. Nature of the temperature dependence of low resistance state and HRS confirmed that RS is caused by the formation and rupture of conductive filaments composed of oxygen vacancies. [ABSTRACT FROM AUTHOR]

The threshold energy barrier for hydrogen desorption from the SiO[sub 2]-Si interface has been assumed to be the Si-H bond energy with the value of 3.6 eV. Based on the uniform Si-H bond energy and diffusion-limited degradation, the time-dependent hot-carrier degradation of metal-oxide-semiconductor (MOS) devices has been described by the so-called power law. In this letter, by investigating the degradation of submicron n-channel MOS devices at various stress conditions and over a large time scale (0.01-10000 s), we present experimental evidence that contradicts the uniform bond energy theory and supports the bond energy variation theory proposed recently by Hess and co-workers [Appl. Phys. Lett. 75, 3147 (1999); Physica B 272, 527 (1999)]. We find that, instead of a constant power factor of n=0.5 predicted by the uniform bond/diffusion-limited energy theory, n varies from ∼0.8 at the initial stress stage to ∼0.2 at the final stress stage consistent with the bond energy variation theory. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Compared to the significant development of creativity studies, individual creativity research has not reached a meaningful consensus regarding the most valid and reliable method for assessing individual creativity. This study revisited 2 of the most popular methods for assessing individual creativity: subjective and objective methods. This study analyzed 1,500 individuals to investigate whether the methods for assessing individual creativity affect the measurement outcomes of individual creativity. Findings indicated that subjective assessments have a smaller variance a higher mean and a moderate but significant correlation with objective assessment methods. Such differences can be motivated by social desirability, consistency motif, illusory superiority, and leniency biases. Based on these findings, this study highlighted the need to acknowledge how subjective and objective assessment methods may affect individual creativity assessment outcomes. [ABSTRACT FROM PUBLISHER]

Precise switchover of numerous resistance states is desirable to achieve repeatable multilevel data storage memory windows. However, this could be hindered by the inherent random nature of oxygen vacancy creation. In this study, oxygen-deficient CeO 2− x thin films were fabricated on indium tin oxide (ITO)-coated/glass substrates using radio-frequency magnetron sputtering at room temperature to obtain simple Ni/CeO 2− x /ITO/glass devices. Multilevel bipolar resistive switching characteristics were investigated by controlling the RESET voltage and current compliance. The device could be regarded as four-level switching memory, controlled by the RESET voltage. An increase in the RESET-stop voltage from −1.5 to −2.0 V increased the Schottky barrier height, leading to an improvement in the ON/OFF ratio. The multilevel resistive switching behavior could be attributed to the formation and partial rupture of conductive filaments owing to interfacial oxygen ion migration. This study shows the potentials of the Ni/CeO 2− x /ITO/glass devices for multilevel data storage resistive random-access memory applications. Unlabelled Image • Oxygen deficient CeO 2-x film is deposited on ITO coated/glass substrate using rf-magnetron sputtering at room temperature. • Multilevel bipolar resistive switching are investigated by controlling the RESET-voltage and current compliance. • Device demonstrated four level switching memory that could be determined by controlling RESET-voltage. • By increasing the RESET-stop voltage from −1.5 to −2.0 V will increases the Schottky barrier height. [ABSTRACT FROM AUTHOR]

Due to paleoparasitology's relatively late beginnings, the fundamental data necessary for any reasonably complete understanding of parasitic infection patterns in Korean history remains insufficient. Especially with respect to ancient samples dating to before the Joseon Dynasty (1392–1910 CE), few cases have been analyzed by parasitological techniques. In the present study, we therefore undertook a series of paleoparasitological examinations of archaeological samples from the ancient Silla Kingdom (57 BCE–935 CE). Specifically, in soil samples obtained from shell midden and mountain top fortress sites, we observed Ascaris lumbricoides , Trichuris trichiura , Dicrocoelid and Taenia sp. eggs. The results of our current investigation of strata and samples from the prosperous first-millennium era of the Silla Kingdom are encouraging for a comprehensive understanding of the parasitic infection patterns in the earlier days of Korean history that could not be obtained by any previous studies. [ABSTRACT FROM AUTHOR]

• A mitochondria-targetable fluorogenic quinone dehydrogenase chemosensor was developed. • Probe consists of the mitochondria-targetable trimethyl lock quinone (TLQ)-linked hemicyanine. • This exhibited fluorescence Off-On and visual color change from yellow to orange. • Probe underwent a fluorogenic reaction through a quinone reduction-sensitive electron transport chain (ETC). • Probe could be used to detect the mitochondrial ETC in the live cells. A trimethyl lock quinone (TLQ)-linked hemicyanine (probe 1) is developed for imaging mitochondrial dehydrogenase activity in the live human cells. In aqueous environment, the system underwent a fluorogenic reduction of TLQ moiety upon incubation with human recombinant NQO1, providing a fluorescence Off-On with a concomitant visual color change from yellow to orange. In contrast to other TLQ-based fluorescent probes, probe 1 is localized to the mitochondria of living cells where little NQO1 exist. And, it can provide a fluorescence turn-on response which was selectively modulated by antimycin A and myxothiazol, a potent inhibitor of the complex III in the electron transfer chain and showed poor response to dicoumarol, a potent inhibitor of NQO1. Likely, probe 1 acts as a fluorogenic chemosensor for the mitochondrial electron transferring reaction in the live cells. [ABSTRACT FROM AUTHOR]

We investigated the effects of the Gibbs free energy difference (∆G o ) and distribution of oxygen vacancies in a bilayer ZnO/ZrO 2 structure. The device exhibited high endurance characteristics of up to 1000 DC repetitive resistive cycles, long retention (104), and a low coefficient of variation of SET and RESET-voltages (6% and 5%, respectively). In addition, X-ray photoelectron spectroscopy (XPS) analysis of the ZnO and ZrO 2 layers indicated that the oxygen vacancies/defects in the ZnO layer (44.13%) were larger than in the ZrO 2 layer (34.11%), and that the oxygen ions of O Zr (65.89%) were larger than those of O Zn (55.87). This XPS analysis confirmed that the differing oxygen vacancy distributions in the ZnO/ZrO 2 layer are responsible for improving the switching performance. The switching behavior, endurance, and retention time strongly depend on the types of electrode and switching materials used. We obtained qualitative and quantitative evidence that ∆G o of the oxide materials plays a significant role in determining the resistive switching characteristics. Bipolar switching mechanisms are explained by considering ∆G o in the ZnO and ZrO 2 layers, where the formation and rupture of conductive filaments are caused by oxygen vacancies. Our findings suggest that a bilayer ZnO/ZrO 2 structure is promising for application to non-volatile memory. • Effects of Gibbs free energy difference and oxygen vacancies distribution in a bilayer ZnO/ZrO 2 structure are studied. • High endurance characteristics of up to 1000 cycles, long data retention (104), and a lower variation are demonstrated • XPS conforms the different oxygen vacancies distribution in two layers are responsible for improving the switching. • Bipolar resistive switching mechanisms are explained by considering Gibbs free energy of ZnO and ZrO 2 layers. [ABSTRACT FROM AUTHOR]

Background: Mitochondrial dysfunction in the thyroid due to defective mitophagy has been observed in lymphocytic thyroiditis (LT). However, the effect of impaired mitophagy on the pathogenesis of LT is not well understood. The aim of this study is to investigate the role of mitophagy dysregulation in the thyroid gland. Methods: We analyzed RNA sequencing data of human thyroid glands with/without LT from Genotype-Tissue Expression (GTEx; n = 653) and performed RNA sequencing in thyroid glands of phosphatase and tensin homolog-induced putative protein kinase 1 ( Pink1 ) knock-out and wild-type mice. We evaluated the phenotypic and histopathologic characteristics of the human ( n = 16) and mouse thyroids. Additionally, we assessed cell proliferation, reactive oxygen species (ROS) production, and cytokine secretion of human thyroid epithelial cells (HTori-3) treated with PINK1 siRNA or a mitophagy inhibitor. Results: We found that expression of PINK1 , a key regulator of mitophagy, was compromised in human thyroids with LT. Thyroid glands of Pink1 -deficient mice exhibited increased inflammatory responses and nodular hyperplasia. Furthermore, mitophagy defects led to the production of pro-inflammatory cytokines and ROS in thyroid cells, resulting in immune cell recruitment. Notably, these mitophagy defects upregulated both the RNA expression and protein secretion of amphiregulin (AREG), an epidermal growth factor receptor (EGFR) ligand, in thyroid cells, while decreasing the protein expression of cAMP response element-binding protein (CREB), a transcription factor that suppresses AREG transcription. Finally, we demonstrated that aberrant cell proliferation in thyroid cells, driven by mitophagy defects, was mitigated after treatment with cetuximab, an EGFR inhibitor. Conclusions: In this study, we observed that mitophagy defects in the thyroid not only intensify inflammation through the accumulation of ROS, cytokine production, and immune cell recruitment but also contribute to hyperplasia via the EGFR pathway, facilitated by increased secretion of AREG from thyroid cells.

Background: Psoriasis is an inflammatory skin disease characterized by the hyperproliferative epidermal keratinocytes and significant immune cells infiltration, leading to cytokines production such as IL-1β, TNF-α, IL-23, and IL-17. Recent study highlights the critical role of IL-1β in the induction and activation of pathogenic Th17 and IL-17-producing γδ T cells, contributing to psoriasis. However, the mechanism underlying IL-1β dysregulation in psoriasis pathogenesis is unclear. Autophagy regulates IL-1β production and has a pleiotropic effect on inflammatory disorders. Previous studies showed controversial role of autophagy in psoriasis pathogenesis, either pro-inflammatory in autophagy-deficient keratinocyte or anti-inflammatory in pharmacologically autophagy-promoting macrophages. Thus, the direct role of autophagy and its therapeutic potential in psoriasis remains unclear., Methods: We used myeloid cell-specific autophagy-related gene 7 (Atg7)-deficient mice and determined the effect of autophagy deficiency in myeloid cells on neutrophilia and disease pathogenesis in an imiquimod-induced psoriasis mouse model. We then assessed the pathogenic mechanism focusing on immune cells producing IL-1β and IL-17 along with gene expression profiles associated with psoriasis in mouse model and public database on patients. Moreover, therapeutic potential of IL-1β blocking in such context was assessed., Results: We found that autophagy deficiency in myeloid cells exacerbated neutrophilic inflammation and disease pathogenesis in mice with psoriasis. This autophagy-dependent effect was associated with a significant increase in IL-1β production from myeloid cells, particularly macrophages, Cxcl2 expression, and IL-17 A producing T cells including γδ T cells. Supporting this, treatment with systemic IL-1 receptor blocking antibody or topical saccharin, a disaccharide suppressing pro-IL-1β expression, led to the alleviation of neutrophilia and psoriatic skin inflammation linked to autophagy deficiency. The pathophysiological relevance of this finding was supported by dysregulation of autophagy-related genes and their correlation with Th17 cytokines in psoriatic skin lesion from patients with psoriasis., Conclusions: Our results suggest that autophagy dysfunction in myeloid cells, especially macrophages, along with IL-1β dysregulation has a causal role in neutrophilic inflammation and psoriasis pathogenesis., (© 2024. The Author(s).)

Background: The use of flash glucose monitoring (FGM) in conjunction with proper education has been reported to improve glycemic control in people with diabetes on insulin therapy. However, there are still few randomized controlled trials on the educational effect, and an ideal educational model has not been established. This study aimed to estimate the efficacy of remote intervention for glycemic control in adults with type 1 diabetes using FGM., Methods: In this single-center, randomized controlled trial, we enrolled adults with type 1 diabetes (HbA1c ≥7.0%). The participants were randomly assigned (1:1) to either FGM use with remote intervention (intervention group) or FGM use only (control group). Changes in glycemic outcomes such as HbA1c levels and continuous glucose monitoring metrics were evaluated at 12 weeks., Results: Among 36 randomized participants (mean age, 44.3 years; mean baseline HbA1c, 8.9%), 34 completed the study. The remote intervention did not significantly reduce HbA1c levels. FGM use significantly improved HbA1c levels by -1.4% and -0.8% in both groups with and without remote intervention, respectively ( P =0.003 and P =0.004, respectively). However, the intervention group showed significant increases in time with glucose in the range of 70-180 mg/dL (TIR; from 49.8% to 60.9%, P =0.001) and significant decreases in time with hyperglycemia ( P =0.002) and mean glucose ( P =0.017), but the control group did not. Moreover, the TIR ( P =0.019), time with hyperglycemia >250 mg/dL ( P =0.019), and coefficient of variation ( P =0.018) were significantly improved in the intervention group compared to the control group. In particular, the CGM metrics improved gradually as the remote intervention was repeated. Furthermore, the intervention group reported higher treatment satisfaction ( P =0.016)., Conclusions: Ongoing, personalized education during FGM use may lead to amelioration of glycemic control in adults with type 1 diabetes, even remotely., Clinical Trial Registration: https://clinicaltrials.gov/ct2/show/NCT04936633, identifier NCT04936633., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Lee, Lee, Park, Kim, Kim, Cho, Han and Song.)