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The origin and early dispersal of speakers of Transeurasian languages-that is, Japanese, Korean, Tungusic, Mongolic and Turkic-is among the most disputed issues of Eurasian population history1-3. A key problem is the relationship between linguistic dispersals, agricultural expansions and population movements4,5. Here we address this question by 'triangulating' genetics, archaeology and linguistics in a unified perspective. We report wide-ranging datasets from these disciplines, including a comprehensive Transeurasian agropastoral and basic vocabulary; an archaeological database of 255 Neolithic-Bronze Age sites from Northeast Asia; and a collection of ancient genomes from Korea, the Ryukyu islands and early cereal farmers in Japan, complementing previously published genomes from East Asia. Challenging the traditional 'pastoralist hypothesis'6-8, we show that the common ancestry and primary dispersals of Transeurasian languages can be traced back to the first farmers moving across Northeast Asia from the Early Neolithic onwards, but that this shared heritage has been masked by extensive cultural interaction since the Bronze Age. As well as marking considerable progress in the three individual disciplines, by combining their converging evidence we show that the early spread of Transeurasian speakers was driven by agriculture.
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Agricultura/história , Arqueologia , Genética Populacional , Migração Humana/história , Idioma/história , Linguística , China , Conjuntos de Dados como Assunto , Mapeamento Geográfico , História Antiga , Humanos , Japão , Coreia (Geográfico) , MongóliaRESUMO
The brain's remarkable and efficient information processing capability is driving research into brain-inspired (neuromorphic) computing paradigms. Artificial aqueous ion channels are emerging as an exciting platform for neuromorphic computing, representing a departure from conventional solid-state devices by directly mimicking the brain's fluidic ion transport. Supported by a quantitative theoretical model, we present easy-to-fabricate tapered microchannels that embed a conducting network of fluidic nanochannels between a colloidal structure. Due to transient salt concentration polarization, our devices are volatile memristors (memory resistors) that are remarkably stable. The voltage-driven net salt flux and accumulation, that underpin the concentration polarization, surprisingly combine into a diffusionlike quadratic dependence of the memory retention time on the channel length, allowing channel design for a specific timescale. We implement our device as a synaptic element for neuromorphic reservoir computing. Individual channels distinguish various time series, that together represent (handwritten) numbers, for subsequent in silico classification with a simple readout function. Our results represent a significant step toward realizing the promise of fluidic ion channels as a platform to emulate the rich aqueous dynamics of the brain.
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Porous carbon is a pivotal material for electrochemical applications. The manufacture of porous carbon has relied on chemical treatments (etching or template) that require processing in all areas of the carbon/carbon precursor. We present a unique approach to preparing porous carbon nanospheres by inhibiting the pyrolytic condensation of polymers. Specifically, the porous carbon nanospheres are obtained by coating a thin film of ZnO on polystyrene spheres. The porosity of the porous carbon nanospheres is controlled by the thickness of the ZnO shell, achieving a BET-specific area of 1,124 m2/g with a specific volume of 1.09 cm3/g. We confirm that under the support force by the ZnO shell, a hierarchical pore structure in which small mesopores are connected by large mesopores is formed and that the pore-associated sp3 defects are enriched. These features allow full utilization of the surface area of the carbon pores. The electrochemical capacitive performance of porous carbon nanospheres was evaluated, achieving a high capacitance of 389 F/g at 1 A/g, capacitance retention of 71% at a 20-fold increase in current density, and stability up to 30,000 cycles. In particular, we achieve a specific area-normalized capacitance of 34.6 µF/cm2, which overcomes the limitations of conventional carbon materials.
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Although recent studies demonstrate active mitochondrial metabolism in cancers, the precise mechanisms through which mitochondrial factors contribute to cancer metastasis remain elusive. Through a customized mitochondrion RNAi screen, we identified succinyl-CoA ligase ADP-forming subunit beta (SUCLA2) as a critical anoikis resistance and metastasis driver in human cancers. Mechanistically, SUCLA2, but not the alpha subunit of its enzyme complex, relocates from mitochondria to the cytosol upon cell detachment where SUCLA2 then binds to and promotes the formation of stress granules. SUCLA2-mediated stress granules facilitate the protein translation of antioxidant enzymes including catalase, which mitigates oxidative stress and renders cancer cells resistant to anoikis. We provide clinical evidence that SUCLA2 expression correlates with catalase levels as well as metastatic potential in lung and breast cancer patients. These findings not only implicate SUCLA2 as an anticancer target, but also provide insight into a unique, noncanonical function of SUCLA2 that cancer cells co-opt to metastasize.
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Neoplasias , Succinato-CoA Ligases , Humanos , Catalase/metabolismo , Grânulos de Estresse , Succinato-CoA Ligases/metabolismo , OxirreduçãoRESUMO
The adolescent social experience is essential for the maturation of the prefrontal cortex in mammalian species. However, it still needs to be determined which cortical circuits mature with such experience and how it shapes adult social behaviors in a sex-specific manner. Here, we examined social-approaching behaviors in male and female mice after postweaning social isolation (PWSI), which deprives social experience during adolescence. We found that the PWSI, particularly isolation during late adolescence, caused an abnormal increase in social approaches (hypersociability) only in female mice. We further found that the PWSI female mice showed reduced parvalbumin (PV) expression in the left orbitofrontal cortex (OFCL). When we measured neural activity in the female OFCL, a substantial number of neurons showed higher activity when mice sniffed other mice (social sniffing) than when they sniffed an object (object sniffing). Interestingly, the PWSI significantly reduced both the number of activated neurons and the activity level during social sniffing in female mice. Similarly, the CRISPR/Cas9-mediated knockdown of PV in the OFCL during late adolescence enhanced sociability and reduced the social sniffing-induced activity in adult female mice via decreased excitability of PV+ neurons and reduced synaptic inhibition in the OFCL Moreover, optogenetic activation of excitatory neurons or optogenetic inhibition of PV+ neurons in the OFCL enhanced sociability in female mice. Our data demonstrate that the adolescent social experience is critical for the maturation of PV+ inhibitory circuits in the OFCL; this maturation shapes female social behavior via enhancing social representation in the OFCL SIGNIFICANCE STATEMENT Adolescent social isolation often changes adult social behaviors in mammals. Yet, we do not fully understand the sex-specific effects of social isolation and the brain areas and circuits that mediate such changes. Here, we found that adolescent social isolation causes three abnormal phenotypes in female but not male mice: hypersociability, decreased PV+ neurons in the left orbitofrontal cortex (OFCL), and decreased socially evoked activity in the OFCL Moreover, parvalbumin (PV) deletion in the OFCL in vivo caused the same phenotypes in female mice by increasing excitation compared with inhibition within the OFCL Our data suggest that adolescent social experience is required for PV maturation in the OFCL, which is critical for evoking OFCL activity that shapes social behaviors in female mice.
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Neurônios , Parvalbuminas , Masculino , Camundongos , Animais , Feminino , Parvalbuminas/metabolismo , Neurônios/fisiologia , Córtex Pré-Frontal/fisiologia , Comportamento Social , Isolamento Social , Interneurônios/fisiologia , MamíferosRESUMO
The ubiquitin system plays pivotal roles in diverse cellular processes, including signal transduction, transcription and translation, organelle quality control, and protein degradation. Recent investigations have revealed the regulatory influence of ubiquitin systems on RNA metabolism. Previously, we reported that the deubiquitinating enzyme, ubiquitin specific peptidase 15 (USP15), promotes deubiquitination of terminal uridylyl transferase 1 (TUT1), a key regulator within the U4/U6 spliceosome, thereby instigating significant alterations in global RNA splicing [1]. In this study, we report that ubiquitin specific peptidase 4 (USP4), a homologous protein to USP15, also exerts control over the ubiquitination status of TUT1. Analogous to USP15, the expression of USP4 results in a reduction of TUT1 ubiquitination. Furthermore, squamous cell carcinoma antigen recognized by T-cells 3 (SART3) collaborates in enhancing the deubiquitinating activity of USP4 towards TUT1. A crucial revelation is that USP4 orchestrates the subnuclear relocation of TUT1 from the nucleolus to the nucleoplasm and facilitates the stability of U6 small nuclear RNA (snRNA). Notably, USP4 has a more profound effect on TUT1 redistribution compared to USP15. Our findings suggest that USP4 intricately modulates the ubiquitination status of TUT1, thereby exerting pronounced effects on the spliceosome functions.
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Nucleotidiltransferases , Proteínas de Ligação a RNA , Spliceossomos , Proteases Específicas de Ubiquitina , Proteínas de Ligação a RNA/metabolismo , Spliceossomos/metabolismo , Ubiquitina/metabolismo , Proteases Específicas de Ubiquitina/genética , Proteases Específicas de Ubiquitina/metabolismo , Ubiquitinação , Humanos , Nucleotidiltransferases/metabolismoRESUMO
Compact but precise feature-extracting ability is core to processing complex computational tasks in neuromorphic hardware. Physical reservoir computing (RC) offers a robust framework to map temporal data into a high-dimensional space using the time dynamics of a material system, such as a volatile memristor. However, conventional physical RC systems have limited dynamics for the given material properties, restricting the methods to increase their dimensionality. This study proposes an integrated temporal kernel composed of a 2-memristor and 1-capacitor (2M1C) using a W/HfO2/TiN memristor and TiN/ZrO2/Al2O3/ZrO2/TiN capacitor to achieve higher dimensionality and tunable dynamics. The kernel elements are carefully designed and fabricated into an integrated array, of which performances are evaluated under diverse conditions. By optimizing the time dynamics of the 2M1C kernel, each memristor simultaneously extracts complementary information from input signals. The MNIST benchmark digit classification task achieves a high accuracy of 94.3% with a (196×10) single-layer network. Analog input mapping ability is tested with a Mackey-Glass time series prediction, and the system records a normalized root mean square error of 0.04 with a 20×1 readout network, the smallest readout network ever used for Mackey-Glass prediction in RC. These performances demonstrate its high potential for efficient temporal data analysis.
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A multi-objective genetic algorithm (MOGA) is a powerful global optimization tool, but its results are considerably affected by the crossover parameter ηc. Finding an appropriate ηc demands too much computing time because MOGA needs be run several times in order to find a good ηc. In this paper, a self-adaptive crossover parameter is introduced in a strategy to adopt a new ηc for every generation while running MOGA. This new scheme has also been adopted for a multi-generation Gaussian process optimization (MGGPO) when producing trial solutions. Compared with the existing MGGPO and MOGA, the MGGPO and MOGA with the new strategy show better performance in nonlinear optimization for the design of low-emittance storage rings.
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Osteogenesis imperfecta (OI) is the most common inherited form of bone fragility and includes a heterogeneous group of genetic disorders that most commonly result from defects associated with type I collagen. Although genetic analyses have been developed, nationwide research on the incidence and associated fractures in OI is lacking. This study aimed to investigate the patterns of OI prevalence, incidence, fracture rate, etc. in South Korea using National Health Insurance Service (NHIS) claims data. We found 1596 patients newly diagnosed with OI between March 2002 and February 2020. We evaluated the incidence, prevalence, and history of fractures, fracture site, prescription of anti-osteoporosis drugs, etc. To compare medical costs, fracture rates, and scoliosis rates, we created a control group comprising patients without OI using 1:1 propensity score matching. The prevalence of OI increased slightly each year, with an annual incidence of 20.20 per 100,000 live births. Mean fracture frequency in OI patients was 17 (2-32) times per patient and the most frequent fracture site was the lower leg. A total of 21.4% patients were prescribed anti-osteoporosis drugs, and the most popular drug was pamidronate. After 1:1 propensity score matching, in terms of scoliosis, OI patients had a 3.91 times higher prevalence of scoliosis than in healthy patients which was statistically significant. The sum of medical care expenses for patients with OI was 3.5 times higher than that for patients without OI. We identified nationwide trends in OI occurrence, fractures, and medication use. This study also highlighted the real-world data of scoliosis and medical costs compared to the control group.
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Background and Objectives: The older members of a population might experience unmet medical needs, despite desiring medical care due to activity limitations driven by their perception of aging. This study conducted a cross-sectional analysis of the association between perceived activity restriction (PAR) due to people's own perception of aging and unmet medical needs (UMN) in late middle-aged and older Koreans based on the Korean National Health and Nutrition Examination Survey (KNHANES). Materials and Methods: The 2016-2020 KNHANES was used to analyze a total of 2008 participants among groups aged 45 years or older by applying individual weights imposed from the raw data. The independent variable of PAR was assessed using self-reported questionnaires based on the global activity limitation indicator. Also, the dependent variable of UMN, referring to the state in which a patient's medical care or service was insufficient, inadequate, or lacking, was assessed using a single question. After excluding missing values, the data on 2008 individuals were analyzed using a chi-square test, weighted logistic regression, and a stratified analysis of gender, age, and the presence of chronic illnesses. Results: The group that experienced PAR had an OR 2.13 higher (odds ratio [OR]: 2.13; 95% confidence interval [CI]: 1.27-3.56) to present UMN than the group that did not experience PAR. Furthermore, the results of the stratified analysis indicated that, in the group of female participants with chronic illness and in the group of elderly people, experiencing PAR was associated with a higher experience of UMN. Conclusions: There was a close association between PAR and UMN. In particular, when PAR occurred in the group of female participants with chronic illness and in the group of elderly people, the incidence rate of UMN was also found to be high. This finding highlights the need for policies and institutional measures to reduce UMN within vulnerable groups with an increased risk of medical inaccessibility due to activity restriction.
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Envelhecimento , Percepção , Idoso , Pessoa de Meia-Idade , Humanos , Feminino , Estudos Transversais , Inquéritos Nutricionais , Doença CrônicaRESUMO
Colloidal colorimetric microsensors enable the in-situ detection of mechanical strains within materials. Enhancing the sensitivity of these sensors to small scale deformation while enabling reversibility of the sensing capability would expand their utility in applications including biosensing and chemical sensing. In this study, we introduce the synthesis of colloidal colorimetric nano-sensors using a simple and readily scalable fabrication method. Colloidal nano sensors are prepared by emulsion-templated assembly of polymer-grafted gold nanoparticles (AuNP). To direct the adsorption of AuNP to the oil-water interface of emulsion droplets, AuNP (≈11nm) are functionalized with thiol-terminated polystyrene (PS, Mn = 11k). These PS-grafted gold nanoparticles are suspended in toluene and subsequently emulsified to form droplets with a diameter of ≈30µm. By evaporating the solvent of the oil-inwater emulsion, we form nanocapsules (AuNC) (diameter < 1µm) decorated by PS-grafted AuNP. To test mechanical sensing, the AuNC are embedded in an elastomer matrix. The addition of a plasticizer reduces the glass transition temperature of the PS brushes, and in turn imparts reversible deformability to the AuNC. The plasmonic peak of the AuNC shifts towards lower wavelengths upon application of uniaxial tensile tension, indicating increased inter-nanoparticle distance, and reverts back as the tension is released.
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Broad spectral response and high photoelectric conversion efficiency are key milestones for realizing multifunctional, low-power optoelectronic devices such as artificial synapse and reconfigurable memory devices. Nevertheless, the wide bandgap and narrow spectral response of metal-oxide semiconductors are problematic for efficient metal-oxide optoelectronic devices such as photonic synapse and optical memory devices. Here, a simple titania (TiO2 )/indium-gallium-zinc-oxide (IGZO) heterojunction structure is proposed for efficient multifunctional optoelectronic devices, enabling widen spectral response range and high photoresponsivity. By overlaying a TiO2 film on IGZO, the light absorption range extends to red light, along with enhanced photoresponsivity in the full visible light region. By implementing the TiO2 /IGZO heterojunction structure, various synaptic behaviors are successfully emulated such as short-term memory/long-term memory and paired pulse facilitation. Also, the TiO2 /IGZO synaptic transistor exhibits a recognition rate up to 90.3% in recognizing handwritten digit images. Moreover, by regulating the photocarrier dynamics and retention behavior using gate-bias modulation, a reconfigurable multilevel (≥8 states) memory is demonstrated using visible light.
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Gammaherpesviruses, including Epstein-Barr virus (EBV), are important human pathogens because they are associated with various tumors. Poly(ADP-ribose) polymerase 1 (PARP1) is a multifunctional host nuclear protein responsible for poly(ADP-ribosyl)ation (PARylation) of target proteins. While PARP1 acts as a negative regulator that suppresses the lytic replication of gammaherpesviruses, viruses are often equipped with various strategies to overcome PARP1 inhibition. However, the mechanisms of how EBV may modulate a repressive host protein, PARP1, are still elusive. In this study, we found that EBV reactivation induced PARP1 downregulation in EBV-infected cells. EBV DNA polymerase processivity factor EA-D, encoded by the BMRF1 gene, directly interacted with the central automodification domain (AD) of PARP1 and was necessary and sufficient to downregulate PARP1 via K29-linked polyubiquitination. Moreover, knockdown of EA-D in B95.8 cells restored PARP1 levels and abrogated the expression of ZTA (also known as ZEBRA), a switch molecule of the EBV life cycle during reactivation. Interestingly, PARP1 PARylated RTA, another key switch molecule, and decreased RTA transactivation on the promoters of the ZTA, BMRF1, and BMLF1 genes. EA-D alleviated the PARylation of RTA and further enhanced RTA-mediated transactivation of these lytic promoters in reporter assays. Taken together, our results suggest that EBV viral processivity factor plays a key role in facilitating lytic replication by inducing PARP1 degradation via its interaction with the PARP1 AD, which is a highly conserved mechanism among gammaherpesviruses to counteract host repressive activity of PARP1 against viral lytic replication. IMPORTANCE PARP1 acts as a negative regulator of lytic replication in EBV. To successfully enter the reactivation cycle, EBV has developed multiple strategies to counteract the host's repressive mechanisms. In this study, we investigated how EBV manipulated the host repressive factor PARP1 to facilitate lytic replication. The EBV processivity factor EA-D downregulated PARP1 in a proteasome-dependent manner via its direct binding with PARP1 AD. The knockdown of EA-D restored the PARP1 level and inhibited ZTA expression during reactivation. Interestingly, PARP1 PARylated RTA and EA-D reduced the PARylation of RTA, thereby promoting the ZTA promoter activity. These results suggest that EA-D plays a key role in EBV lytic replication by inducing PARP1 degradation in addition to supporting DNA replication as a viral processivity factor. Given that the KSHV processivity factor also induces PARP1 degradation and enhances RTA function, gammaherpesviruses share a conserved molecular mechanism to overcome the inhibitory effects of PARP1, promoting lytic replication.
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Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Humanos , Fator D do Complemento/genética , Infecções por Vírus Epstein-Barr/genética , Regulação Viral da Expressão Gênica , Herpesvirus Humano 4/genética , Regiões Promotoras Genéticas , Replicação Viral/genética , Poli(ADP-Ribose) Polimerases/metabolismoRESUMO
OBJECTIVES: This study aimed to examine the association of absolute and relative hand grip strength (HGS) with the risk of all-cause mortality among middle-aged and old-aged people in South Korea. Considering that both absolute HGS and relative HGS could be effective measures, an in-depth investigation is necessary to compare the effects of both measures on mortality. METHODS: Data of 9,102 participants, derived from the Korean Longitudinal Study of Aging from 2006 to 2018, were examined. HGS was divided into two categories: absolute HGS and relative HGS (defined as HGS divided by body mass index). The risk of all-cause mortality was the dependent variable. Cox proportional hazard regression was used to analyze the association between HGS and all-cause mortality. RESULTS: The average of absolute and relative HGS were 25.6 ± 8.7 kg and 1.1 ± 0.4 kg/BMI, respectively. The all-cause mortality rate decreased by 3.2% as absolute HGS increased by 1 kg (adjusted hazard ratio [HR] = 0.968, 95% CI = 0.958-0.978). An increase in relative HGS by 1 kg/BMI was associated with a 22% reduction in risk of all-cause mortality (adjusted HR = 0.780, 95% CI = 0.634-0.960). Individuals with more than two chronic diseases, there was a decrease in all-cause mortality as absolute HGS increased by 1 kg and relative HGS by 1 kg/BMI (absolute HGS; adjusted HR = 0.97, 95% CI = 0.959-0.982, relative HGS; adjusted HR = 0.483, 95% CI = 0.325-0.718). CONCLUSIONS: Our study findings showed that both absolute and relative HGS were inversely associated with the risk of all-cause mortality; a higher absolute/relative HGS was associated with a lower risk of all-cause mortality. Moreover, these findings highlight the importance of improving HGS to alleviate the burden of adverse health problems.
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Envelhecimento , Força da Mão , Mortalidade , Idoso , Humanos , Pessoa de Meia-Idade , Povo Asiático , Índice de Massa Corporal , Estudos Longitudinais , República da CoreiaRESUMO
BACKGROUND: This study investigated the relationship between fibroblast growth factor 21 (FGF21) levels and growth in children with growth hormone deficiency (GHD) and idiopathic short stature (ISS), and the effects of the FGF21 level on response to growth hormone (GH) treatment. METHODS: We included 171 pre-pubertal children with a GHD (n = 54), ISS (n = 46), and normal height (n = 71). Fasting FGF21 levels were measured at baseline and every 6 months during GH treatment. Factors associated with growth velocity (GV) after GH therapy were investigated. RESULTS: The FGF21 level was higher in short children than in the controls without significant difference between the GHD and ISS groups. In the GHD group, the FGF21 level was inversely associated with the free fatty acid (FFA) level at baseline (r = -0.28, P = 0.039), however, was positively correlated with the FFA level at 12 months (r = 0.62, P = 0.016). The GV over 12 months of GH therapy was positively associated with the delta insulin-like growth factor 1 level (ß = 0.003, P = 0.020). The baseline log-transformed FGF21 level was inversely associated with GV with marginal significance (ß = -0.64, P = 0.070). CONCLUSION: The FGF21 level was higher in children of short stature, both those with GHD and the ISS, than in children with normal growth. The pretreatment FGF21 level negatively affected the GV of children with GH-treated GHD. These results suggest the existence of a GH/FFA/FGF21 axis in children.
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Nanismo Hipofisário , Hormônio do Crescimento Humano , Humanos , Criança , Transtornos do Crescimento , Fatores de Crescimento de Fibroblastos , Fator de Crescimento Insulin-Like I , EstaturaRESUMO
BACKGROUND: While the importance of mental health is well-recognized in the field of occupational health, implementation of effective strategies in the workplace has been limited by gaps in infrastructure, program comprehensiveness, coverage, and adherence. The authors developed a Screening, Brief Intervention, and Referral to Treatment (SBIRT) model based occupational mental health intervention, and implemented in a web-based format with a smartphone application. METHODS: The SBIRT-based intervention was developed by a multidisciplinary team, including occupational health physicians, nurses, psychiatrists, and software developers. The following mental health areas were included, based on outcomes of an epidemiological survey conducted: insomnia, depression, anxiety, problematic alcohol use, and suicidal risk. The viability of the two-step evaluation process utilizing a combination of the brief version and the full-length version of the questionnaire was examined using responses from the survey. The intervention was adjusted according to the survey results and expert opinions. RESULTS: The epidemiological survey included 346 employees who completed the long-form version of mental health scales. These data were the used to confirm the diagnostic value of using a combination of short-form and long-form version of the scales for screening in the SBIRT model. The model uses a smartphone application for screening, provision of psychoeducation, and for surveillance. The universal methods of the model ensure it can be implemented by all occupational managers, regardless of their specialization in mental health. In addition to the two-step screening procedure to identify employees at-risk for mental health problems, the model includes a stepped care approach, based on risk stratification, to promote mental health education, management, and follow-up for continuous care. CONCLUSION: The SBIRT model-based intervention provides an easy-to-implement approach for the management of mental health in the workplace. Further studies are required to examine the effectiveness and feasibility of the model.
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Saúde Ocupacional , Transtornos Relacionados ao Uso de Substâncias , Humanos , Intervenção em Crise , Smartphone , Saúde Mental , Encaminhamento e Consulta , Inquéritos e Questionários , Internet , Programas de Rastreamento/métodos , Transtornos Relacionados ao Uso de Substâncias/diagnósticoRESUMO
This paper proposes a near-central camera model and its solution approach. 'Near-central' refers to cases in which the rays do not converge to a point and do not have severely arbitrary directions (non-central cases). Conventional calibration methods are difficult to apply in such cases. Although the generalized camera model can be applied, dense observation points are required for accurate calibration. Moreover, this approach is computationally expensive in the iterative projection framework. We developed a noniterative ray correction method based on sparse observation points to address this problem. First, we established a smoothed three-dimensional (3D) residual framework using a backbone to avoid using the iterative framework. Second, we interpolated the residual by applying local inverse distance weighting on the nearest neighbor of a given point. Specifically, we prevented excessive computation and the deterioration in accuracy that may occur in inverse projection through the 3D smoothed residual vectors. Moreover, the 3D vectors can represent the ray directions more accurately than the 2D entities. Synthetic experiments show that the proposed method can achieve prompt and accurate calibration. The depth error is reduced by approximately 63% in the bumpy shield dataset, and the proposed approach is noted to be two digits faster than the iterative methods.
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Calibragem , Análise por ConglomeradosRESUMO
Research on video anomaly detection has mainly been based on video data. However, many real-world cases involve users who can conceive potential normal and abnormal situations within the anomaly detection domain. This domain knowledge can be conveniently expressed as text descriptions, such as "walking" or "people fighting", which can be easily obtained, customized for specific applications, and applied to unseen abnormal videos not included in the training dataset. We explore the potential of using these text descriptions with unlabeled video datasets. We use large language models to obtain text descriptions and leverage them to detect abnormal frames by calculating the cosine similarity between the input frame and text descriptions using the CLIP visual language model. To enhance the performance, we refined the CLIP-derived cosine similarity using an unlabeled dataset and the proposed text-conditional similarity, which is a similarity measure between two vectors based on additional learnable parameters and a triplet loss. The proposed method has a simple training and inference process that avoids the computationally intensive analyses of optical flow or multiple frames. The experimental results demonstrate that the proposed method outperforms unsupervised methods by showing 8% and 13% better AUC scores for the ShanghaiTech and UCFcrime datasets, respectively. Although the proposed method shows -6% and -5% than weakly supervised methods for those datasets, in abnormal videos, the proposed method shows 17% and 5% better AUC scores, which means that the proposed method shows comparable results with weakly supervised methods that require resource-intensive dataset labeling. These outcomes validate the potential of using text descriptions in unsupervised video anomaly detection.
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A camera equipped with a transparent shield can be modeled using the pinhole camera model and residual error vectors defined by the difference between the estimated ray from the pinhole camera model and the actual three-dimensional (3D) point. To calculate the residual error vectors, we employ sparse calibration data consisting of 3D points and their corresponding 2D points on the image. However, the observation noise and sparsity of the 3D calibration points pose challenges in determining the residual error vectors. To address this, we first fit Gaussian Process Regression (GPR) operating robustly against data noise to the observed residual error vectors from the sparse calibration data to obtain dense residual error vectors. Subsequently, to improve performance in unobserved areas due to data sparsity, we use an additional constraint; the 3D points on the estimated ray should be projected to one 2D image point, called the ray constraint. Finally, we optimize the radial basis function (RBF)-based regression model to reduce the residual error vector differences with GPR at the predetermined dense set of 3D points while reflecting the ray constraint. The proposed RBF-based camera model reduces the error of the estimated rays by 6% on average and the reprojection error by 26% on average.
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In resistive switching memories or artificial synaptic devices, halide perovskites have attracted attention for their unusual features such as rapid ion migration, adjustable composition, and facile synthesis. Herein, the environmentally friendly and highly air stable CsCu2I3 perovskite films are used as the active layer in the Au/CsCu2I3/ITO/glass artificial synapses. The device shows variable synaptic plasticities such as long-term and short-term synaptic plasticity, paired-pulse facilitation, and spike-timing-dependent plasticity by combining potentiation and depression along the formation of conductive filaments. The performances of the devices are maintained for 160 days under ambient conditions. Additionally, the accuracy evaluation of the CsCu2I3-based artificial synapses performs exceptionally well with the MNIST and Fashion MNIST data sets, demonstrating high learning accuracy in deep neural networks. Using the novel B-site engineered halide perovskite material with extreme air stability, this study paves the way for artificial synaptic devices for next-generation in-memory hardware.