Beyond the Blockchain Address: Zero-Knowledge Address Abstraction

Integrating traditional Internet (web2) identities with blockchain (web3) identities presents considerable obstacles. Conventional solutions typically employ a mapping strategy, linking web2 identities directly to specific blockchain addresses. However, this method can lead to complications such as fragmentation of identifiers across disparate networks. To address these challenges, we propose a novel scheme, Address Abstraction (AA), that circumvents the need for direct mapping. AA scheme replaces the existing blockchain address system while maintaining essential properties including a unique identifier, immutability of requests, and privacy preservation. This capability allows users to interact with the blockchain via their web2 identities, irrespective of the specific blockchain address, thereby eliminating limitations tied to a blockchain-specific address system. This mechanism fosters the seamless integration of web2 identities within the web3, in addition, promotes cross-chain compatibility. We also provide an application of AA, denoted as zero-knowledge Address Abstraction (zkAA). It mainly leverages the zero-knowledge proofs to ensure the properties of AA. zkAA has been implemented as a smart contract — compatible with any existing contract-enabled blockchains. Our evaluation of zkAA on Ethereum demonstrates its efficiency. The average cost for registering an abstracted identity is approximate \$7.66, whereas publishing an abstracted transaction costs around \$4.75. In contrast, on Polygon, the associated costs are markedly lower: \$0.02 for registration and \$0.01 for publication, as of January 13, 2023. This empirical evaluation substantiates the feasibility of our proposed solution

CdS/CdSe co-sensitized brookite H:TiO2 nanostructures: Charge carrier dynamics and photoelectrochemical hydrogen generation

In this study, we have synthesized CdS/CdSe co-sensitized brookite TiO2 nanostructures with hydrogen doping (H:TiO2/CdS/CdSe) in a facile solution reaction and studied their PEC performances. Compared to undoped brookite TiO2, the H:TiO2/CdS/CdSe composites exhibit much enhanced photocurrent generation, which originates from the improved charge transfer kinetics endowed by hydrogen doping and sensitization. Time-resolved photoluminescence (PL) and electrochemical impendence spectroscopy (EIS) are employed to explore the charge transfer dynamics between sensitizers and TiO2 and charge carrier kinetics at the semiconductor/electrolyte interface. According to the analytical results, sensitizations of TiO2 are found to enhance the charge separation efficiency. Besides, the hydrogen doping into TiO2 generates oxygen vacancy states, providing additional charge transfer pathway and prohibiting charge recombination, beneficial for enhancing the PEC performances as well. Based on the charge dynamics data, we further develop charge transfer models for TiO2/CdS/CdSe and H:TiO2/CdS/CdSe. The findings from this work can help understanding the charge transfer dynamics in brookite TiO(2)based composite systems as well as designing versatile photoelectrodes for solar energy conversion.1113sciescopu

The Potential of Chatbots for Emotional Support and Promoting Mental Well-Being in Different Cultures: Mixed Methods Study

BACKGROUND: Artificial intelligence chatbot research has focused on technical advances in natural language processing and validating the effectiveness of human-machine conversations in specific settings. However, real-world chat data remain proprietary and unexplored despite their growing popularity, and new analyses of chatbot uses and their effects on mitigating negative moods are urgently needed. OBJECTIVE: In this study, we investigated whether and how artificial intelligence chatbots facilitate the expression of user emotions, specifically sadness and depression. We also examined cultural differences in the expression of depressive moods among users in Western and Eastern countries. METHODS: This study used SimSimi, a global open-domain social chatbot, to analyze 152,783 conversation utterances containing the terms depress and sad in 3 Western countries (Canada, the United Kingdom, and the United States) and 5 Eastern countries (Indonesia, India, Malaysia, the Philippines, and Thailand). Study 1 reports new findings on the cultural differences in how people talk about depression and sadness to chatbots based on Linguistic Inquiry and Word Count and n-gram analyses. In study 2, we classified chat conversations into predefined topics using semisupervised classification techniques to better understand the types of depressive moods prevalent in chats. We then identified the distinguishing features of chat-based depressive discourse data and the disparity between Eastern and Western users. RESULTS: Our data revealed intriguing cultural differences. Chatbot users in Eastern countries indicated stronger emotions about depression than users in Western countries (positive: P<.001; negative: P=.01); for example, Eastern users used more words associated with sadness (P=.01). However, Western users were more likely to share vulnerable topics such as mental health (P<.001), and this group also had a greater tendency to discuss sensitive topics such as swear words (P<.001) and death (P<.001). In addition, when talking to chatbots, people expressed their depressive moods differently than on other platforms. Users were more open to expressing emotional vulnerability related to depressive or sad moods to chatbots (74,045/148,590, 49.83%) than on social media (149/1978, 7.53%). Chatbot conversations tended not to broach topics that require social support from others, such as seeking advice on daily life difficulties, unlike on social media. However, chatbot users acted in anticipation of conversational agents that exhibit active listening skills and foster a safe space where they can openly share emotional states such as sadness or depression. CONCLUSIONS: The findings highlight the potential of chatbot-assisted mental health support, emphasizing the importance of continued technical and policy-wise efforts to improve chatbot interactions for those in need of emotional assistance. Our data indicate the possibility of chatbots providing helpful information about depressive moods, especially for users who have difficulty communicating emotions to other humans. ©Hyojin Chin, Hyeonho Song, Gumhee Baek, Mingi Shin, Chani Jung, Meeyoung Cha, Junghoi Choi, Chiyoung Cha. Originally published in the Journal of Medical Internet Research (https://www.jmir.org), 20.10.2023.11Nsciescopu

Elevated id2 expression results in precocious neural stem cell depletion and abnormal brain development.

Id2 is a helix-loop-helix transcription factor essential for normal development, and its expression is dysregulated in many human neurological conditions. Although it is speculated that elevated Id2 levels contribute to the pathogenesis of these disorders, it is unknown whether dysregulated Id2 expression is sufficient to perturb normal brain development or function. Here, we show that mice with elevated Id2 expression during embryonic stages develop microcephaly, and that females in particular are prone to generalized tonic-clonic seizures. Analyses of Id2 transgenic brains indicate that Id2 activity is highly cell context specific: elevated Id2 expression in naive neural stem cells (NSCs) in early neuroepithelium induces apoptosis and loss of NSCs and intermediate progenitors. Activation of Id2 in maturing neuroepithelium results in less severe phenotypes and is accompanied by elevation of G1 cyclin expression and p53 target gene expression. In contrast, activation of Id2 in committed intermediate progenitors has no significant phenotype. Functional analysis with Id2-overexpressing and Id2-null NSCs shows that Id2 negatively regulates NSC self-renewal in vivo, in contrast to previous cell culture experiments. Deletion of p53 function from Id2-transgenic brains rescues apoptosis and results in increased incidence of brain tumors. Furthermore, Id2 overexpression normalizes the increased self-renewal of p53-null NSCs, suggesting that Id2 activates and modulates the p53 pathway in NSCs. Together, these data suggest that elevated Id2 expression in embryonic brains can cause deregulated NSC self-renewal, differentiation, and survival that manifest in multiple neurological outcomes in mature brains, including microcephaly, seizures, and brain tumors. STEM CELLS 2013;31:1010-1021

Large Transconductance of Electrochemical Transistors Based on Fluorinated Donor-Acceptor Conjugated Polymers

Organic electrochemical transistors (OECTs) have enor-mous potential for use in biosignal amplifiers, analyte sensors, and neuromorphic electronics owing to their exceptionally large trans-conductance. However, it is challenging to simultaneously achieve high charge carrier mobility and volumetric capacitance, the two most important figures of merit in OECTs. Herein, a method of achieving high-performance OECT with donor-acceptor conjugated copolymers by introducing fluorine units is proposed. A series of cyclopentadithiophene- benzothiadiazole (CDT-BT) copolymers for use in high-performance OECTs with enhanced charge carrier mobility (from 0.65 to 1.73 cm2 center dot V-1 center dot s-1) and extended volumetric capacitance (from 44.8 to 57.6 F center dot cm-3) by fluorine substitution is achieved. The increase in the volumetric capacitance of the fluorinated polymers is attributed to either an increase in the volume at which ions can enter the film or a decrease in the effective distance between the ions and polymer backbones. The fluorine substitution increases the backbone planarity of the CDT-BT copolymers, enabling more efficient charge carrier transport. The fluorination strategy of this work suggests the more versatile use of conjugated polymers for high-performance OECTs

Chemically Engineered Au–Ag Plasmonic Nanostructures to Realize Large Area and Flexible Metamaterials

We developed a simple and systematic method to fabricate optically tunable and thermally and chemically stable Au–Ag nanocrystal-based plasmonic metamaterials. An Ag nanocrystal-based metamaterial with desirable optical properties was fabricated via nanoimprinting and ligand-exchange process. Its optical properties were controlled by selectively substituting Ag atoms with Au atoms through a spontaneous galvanic replacement reaction. The developed Au–Ag-based metamaterials provide excellent tunable plasmonic properties required for various applications in the visible and near-infrared regions by controlling the Au–Ag composition according to the conditions of the galvanic displacement. Furthermore, their thermal and chemical stabilities significantly improved because of the protective Au thin layer on the surface. Using this developed process, chemically and thermally stable and flexible plasmonic metamaterials were successfully fabricated on a flexible polyester terephthalate substrate

Fluorescence-based immunosensor using three-dimensional CNT network structure for sensitive and reproducible detection of oral squamous cell carcinoma biomarker

A hierarchical three-dimensional network of carbon nanotubes on Si pillar substrate (3DN-CNTs) was developed for the accurate detection of oral squamous cell carcinoma (OSCC) in clinical saliva samples. The 3DN-CNTs were uniformly coated with a layer of aluminum oxides to enhance structural stability during biomarker detection. Cytokeratin-19 antigen (Cyfra 21-1) was utilized as a model biomarker of OSCC for fluorescence-based immunosensor using 3DN-CNTs (3DN-CNTs sensor). The 3DN-CNTs sensor enhances the sensitivity of Cyfra 21-1 detection by increasing the density of immobilized antibody through high surface area of 3DN-CNTs and enhancing the accessibility of biomolecules through the ordered pathway of hierarchical structure. The reliable detection limit for sensing of Cyfra 21-1 was estimated as in the level of 0.5 ng/mL and the quantitative estimation of Cyfra 21-1 was analyzed by 4-parameter logistic (4-PL) model for curve-fitting analysis. Clinical applicability of 3DN-CNTs sensor was evaluated through correlation with the commercially available electrochemiluminescence (ECL) detection system in the hospital. The assay results of the two systems for clinical saliva samples showed a good linear correlation. The 3DN-CNTs sensor offers great potential for accurate diagnosis of OSCC using Cyfra 21-1 biomarker in clinical fluids.NRF (Natl Research Foundation, S’pore)MOE (Min. of Education, S’pore

Elucidation of Relevant Neuroinflammation Mechanisms Using Gene Expression Profiling in Patients with Amyotrophic Lateral Sclerosis

<div><p>Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder characterized by damage of motor neurons. Recent reports indicate that inflammatory responses occurring within the central nervous system contribute to the pathogenesis of ALS. We aimed to investigate disease-specific gene expression associated with neuroinflammation by conducting transcriptome analysis on fibroblasts from three patients with sporadic ALS and three normal controls. Several pathways were found to be upregulated in patients with ALS, among which the toll-like receptor (TLR) and NOD-like receptor (NLR) signaling pathways are related to the immune response. Genes—toll-interacting protein (<i>TOLLIP</i>), mitogen-activated protein kinase 9 (<i>MAPK9</i>), interleukin-1β (<i>IL-1β</i>), interleukin-8 (<i>IL-8</i>), and chemokine (C-X-C motif) ligand 1 (<i>CXCL1</i>)—related to these two pathways were validated using western blotting. This study validated the genes that are associated with TLR and NLR signaling pathways from different types of patient-derived cells. Not only fibroblasts but also induced pluripotent stem cells (iPSCs) and neural rosettes from the same origins showed similar expression patterns. Furthermore, expression of TOLLIP, a regulator of TLR signaling pathway, decreased with cellular aging as judged by changes in its expression through multiple passages. TOLLIP expression was downregulated in ALS cells under conditions of inflammation induced by lipopolysaccharide. Our data suggest that the TLR and NLR signaling pathways are involved in pathological innate immunity and neuroinflammation associated with ALS and that TOLLIP, MAPK9, IL-1β, IL-8, and CXCL1 play a role in ALS-specific immune responses. Moreover, changes of TOLLIP expression might be associated with progression of ALS.</p></div

Validation of identified genes by RT-qPCR and western blotting.

<p>(A) Quantitative comparison of relative gene expressions between normal subjects and ALS patients by RT-qPCR. (B) TOLLIP, IL-1β, IL-8, MAPK9, and CXCL1 proteins were overexpressed in the subjects with ALS by western blotting. (C) Comparison of relative expression from normal subjects and patients with ALS for the five proteins verified by western blotting. *<i>P</i> < 0.05, ^†<i>P</i> < 0.1</p

RT-PCR verification of genes identified in transcriptome analysis.

<p>(A) RT-PCR analysis of 11 genes. (B) Comparison of relative gene expression in normal subjects and patients with ALS. Eleven genes from the Toll-like receptor and NOD-like receptor signaling pathways were verified using RT-PCR and genes—<i>CD14</i>, interferon-α/β receptor-1 (<i>IFNAR-1</i>), toll-interacting protein (<i>TOLLIP</i>), mitogen-activated protein kinase 9 (<i>MAPK9</i>), interleukin 1 beta (<i>IL-1β</i>), interleukin 8 (<i>IL-8</i>), and chemokine (C-X-C motif) ligand 1 (<i>CXCL1</i>)—were upregulated in the ALS group. *<i>P</i> < 0.05, ^†<i>P</i> < 0.1</p