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Background Visual assessment of amyloid PET scans relies on the availability of radiologist expertise, whereas quantification of amyloid burden typically involves MRI for processing and analysis, which can be computationally expensive. Purpose To develop a deep learning model to classify minimally processed brain PET scans as amyloid positive or negative, evaluate its performance on independent data sets and different tracers, and compare it with human visual reads. Materials and Methods This retrospective study used 8476 PET scans (6722 patients) obtained from late 2004 to early 2023 that were analyzed across five different data sets. A deep learning model, AmyloidPETNet, was trained on 1538 scans from 766 patients, validated on 205 scans from 95 patients, and internally tested on 184 scans from 95 patients in the Alzheimer's Disease Neuroimaging Initiative (ADNI) fluorine 18 (18F) florbetapir (FBP) data set. It was tested on ADNI scans using different tracers and scans from independent data sets. Scan amyloid positivity was based on mean cortical standardized uptake value ratio cutoffs. To compare with model performance, each scan from both the Centiloid Project and a subset of the Anti-Amyloid Treatment in Asymptomatic Alzheimer's Disease (A4) study were visually interpreted with a confidence level (low, intermediate, high) of amyloid positivity/negativity. The area under the receiver operating characteristic curve (AUC) and other performance metrics were calculated, and Cohen κ was used to measure physician-model agreement. Results The model achieved an AUC of 0.97 (95% CI: 0.95, 0.99) on test ADNI 18F-FBP scans, which generalized well to 18F-FBP scans from the Open Access Series of Imaging Studies (AUC, 0.95; 95% CI: 0.93, 0.97) and the A4 study (AUC, 0.98; 95% CI: 0.98, 0.98). Model performance was high when applied to data sets with different tracers (AUC ≥ 0.97). Other performance metrics provided converging evidence. Physician-model agreement ranged from fair (Cohen κ = 0.39; 95% CI: 0.16, 0.60) on a sample of mostly equivocal cases from the A4 study to almost perfect (Cohen κ = 0.93; 95% CI: 0.86, 1.0) on the Centiloid Project. Conclusion The developed model was capable of automatically and accurately classifying brain PET scans as amyloid positive or negative without relying on experienced readers or requiring structural MRI. Clinical trial registration no. NCT00106899 © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Bryan and Forghani in this issue.
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Enfermedad de Alzheimer , Encéfalo , Aprendizaje Profundo , Tomografía de Emisión de Positrones , Humanos , Tomografía de Emisión de Positrones/métodos , Estudios Retrospectivos , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/clasificación , Masculino , Femenino , Anciano , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Amiloide/metabolismo , Anciano de 80 o más AñosRESUMEN
Extracellular matrix metalloproteinase inducer CD147 is a glycoprotein on the cell surface. There is minimal expression of CD147 in normal epithelial and fetal tissues, but it is highly expressed in a number of aggressive tumors. CD147 has been implicated in pan-cancer immunity and progression. With the development of CD147-targeting therapeutic strategy, accurate detection of CD147 expression in tumors and its changes during the therapy is necessary. In this study we constructed a novel radiotracer by labeling the anti-CD147 mAb with radionuclide 124/125I (124/125I-anti-CD147) for noninvasive detection of CD147 expression in pan-cancers, and characterized its physicochemical properties, affinity, metabolic characteristics, biodistribution and immunoPET imaging with 124I-IgG and 18F-FDG as controls. By examining the expression of CD147 in cancer cell lines, we found high CD147 expression in colon cancer cells LS174T, FADU human pharyngeal squamous cancer cells and 22RV1 human prostate cancer cells, and low expression of CD147 in human pancreatic cancer cells ASPC1 and human gastric cancer cells BGC823. 124/125I-anti-CD147 was prepared using N-bromine succinimide (NBS) as oxidant and purified by PD-10 column. Its radiochemical purity (RCP) was over 99% and maintained over 85% in saline or 5% human serum albumin (HSA) for more than 7 d; the RCP of 125I-anti-CD147 in blood was over 90% at 3 h post injection (p.i.) in healthy mice. The Kd value of 125I-anti-CD147 to CD147 protein was 6.344 nM, while that of 125I-IgG was over 100 nM. 125I-anti-CD147 showed much greater uptake in CD147 high-expression cancer cells compared to CD147 low-expression cancer cells. After intravenous injection in healthy mice, 125I-anti-CD147 showed high initial uptake in blood pool and liver, the uptake was decreased with time. The biological half-life of distribution and clearance phases in healthy mice were 0.63 h and 19.60 h, respectively. The effective dose of 124I-anti-CD147 was estimated as 0.104 mSv/MBq. We conducted immunoPET imaging in tumor-bearing mice, and demonstrated a significantly higher tumor-to-muscle ratio of 124I-anti-CD147 compared to that of 124I-IgG and 18F-FDG in CD147 (+) tumors. The expression levels of CD147 in cells and tumors were positively correlated with the maximum standardized uptake value (SUVmax) (P < 0.01). In conclusion, 124/125I-anti-CD147 displays high affinity to CD147, and represents potential for the imaging of CD147-positive tumors. The development of 124I-anti-CD147 may provide new insights into the regulation of tumor microenvironment and formulation of precision diagnosis and treatment programs for tumors.
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Fluorodesoxiglucosa F18 , Neoplasias de la Próstata , Masculino , Humanos , Ratones , Animales , Distribución Tisular , Radiofármacos , Radioisótopos de Yodo , Inmunoglobulina G , Línea Celular Tumoral , Microambiente TumoralRESUMEN
BACKGROUND: Essential tremor (ET) and Parkinson's disease (PD) are the two most prevalent movement disorders, sharing several overlapping tremor clinical features. Although growing evidence pointed out that changes in similar brain network nodes are associated with these two diseases, the brain network topological properties are still not very clear. OBJECTIVE: The combination of graph theory analysis with machine learning (ML) algorithms provides a promising way to reveal the topological pathogenesis in ET and tremor-dominant PD (tPD). METHODS: Topological metrics were extracted from Resting-state functional images of 86 ET patients, 86 tPD patients, and 86 age- and sex-matched healthy controls (HCs). Three steps were conducted to feature dimensionality reduction and four frequently used classifiers were adopted to discriminate ET, tPD, and HCs. RESULTS: A support vector machine classifier achieved the best classification performance of four classifiers for discriminating ET, tPD, and HCs with 89.0% mean accuracy (mACC) and was used for binary classification. Particularly, the binary classification performances among ET vs. tPD, ET vs. HCs, and tPD vs. HCs were with 94.2% mACC, 86.0% mACC, and 86.3% mACC, respectively. The most power discriminative features were mainly located in the default, frontal-parietal, cingulo-opercular, sensorimotor, and cerebellum networks. Correlation analysis results showed that 2 topological features negatively and 1 positively correlated with clinical characteristics. CONCLUSIONS: These results demonstrated that combining topological metrics with ML algorithms could not only achieve high classification accuracy for discrimination ET, tPD, and HCs but also help to reveal the potential brain topological network pathogenesis in ET and tPD.
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Encéfalo , Temblor Esencial , Aprendizaje Automático , Imagen por Resonancia Magnética , Enfermedad de Parkinson , Humanos , Temblor Esencial/diagnóstico , Temblor Esencial/diagnóstico por imagen , Enfermedad de Parkinson/diagnóstico por imagen , Enfermedad de Parkinson/diagnóstico , Enfermedad de Parkinson/fisiopatología , Femenino , Masculino , Anciano , Persona de Mediana Edad , Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Máquina de Vectores de Soporte , Diagnóstico DiferencialRESUMEN
Children are often third-party observers of conversations between informants and receivers. Although 5- and 6-year-olds can identify and reject informants' false testimony, it remains unclear whether they expect others to do the same. Accurately assessing others' impressions of informants and their testimony in a conversational setting is essential for children's navigation of the social world. Using a novel second-order lie detection task, the current study examined whether 4- to 7-year-olds (N = 74; Mage = 69 months) take receivers' epistemic states into account when predicting whether a receiver would think an informant is truthful or deceptive. We pitted children's firsthand observations of reality against informants' false testimony while manipulating receivers' perceptual access to a sticker-hiding event. Results showed that when the receiver had perceptual access and was knowledgeable, children predicted that the receiver would think the informant is lying. Critically, when the receiver lacked perceptual access and was ignorant, children were significantly more likely to predict that the receiver would think the informant is telling the truth. Second-order theory of mind and executive function strengthened this effect. Findings are interpreted using a dual-process framework and provide new insights into children's understanding of others' selective trust and susceptibility to deception.
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Señales (Psicología) , Juicio , Niño , Humanos , Preescolar , Confianza , Función Ejecutiva , DecepciónRESUMEN
The distribution of cellular resources across bacterial proteins has been quantified through phenomenological growth laws. Here, we describe a complementary bacterial growth law for RNA composition, emerging from optimal cellular resource allocation into ribosomes and ternary complexes. The predicted decline of the tRNA/rRNA ratio with growth rate agrees quantitatively with experimental data. Its regulation appears to be implemented in part through chromosomal localization, as rRNA genes are typically closer to the origin of replication than tRNA genes and thus have increasingly higher gene dosage at faster growth. At the highest growth rates in E. coli, the tRNA/rRNA gene dosage ratio based on chromosomal positions is almost identical to the observed and theoretically optimal tRNA/rRNA expression ratio, indicating that the chromosomal arrangement has evolved to favor maximal transcription of both types of genes at this condition.
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Escherichia coli/genética , Genoma Bacteriano/genética , Ribosomas/genética , Transcripción Genética , Cromosomas Bacterianos/genética , Escherichia coli/crecimiento & desarrollo , Dosificación de Gen/genética , ARN Bacteriano/genética , ARN Ribosómico/genética , ARN de Transferencia/genéticaRESUMEN
The direct 1,6-nucleophilic difluoromethylation, trifluoromethylation, and difluoroalkylation of para-quinone methides (p-QMs) with Me3SiRf (Rf = CF2H, CF3, CF2CF3, CF2COOEt, and CF2SPh) under mild conditions are described. Although Me3SiCF2H shows lower reactivity than Me3SiCF3, it can react with p-QMs promoted by CsF/18-Crown-6 to give structurally diverse difluoromethyl products in good yields. The products can then be further converted into fluoroalkylated para-quinone methides and α-fluoroalkylated diarylmethanes.
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The increasing interest in two-dimensional materials with unique crystal structures and novel band characteristics has provided numerous new strategies and paradigms in the field of photodetection. However, as the demand for wide-spectrum detection increases, the size of integrated systems and the limitations of mission modules pose significant challenges to existing devices. In this paper, we present a van der Waals heterostructure photodetector based on Ta2NiSe5/WSe2, leveraging the inherent characteristics of heterostructures. Our results demonstrate that this detector exhibits excellent broad-spectrum detection ability from the visible to the infrared bands at room temperature, achieving an extremely high on/off ratio, without the need for an external bias voltage. Furthermore, compared to a pure material detector, it exhibits a fast response and low dark currents (~3.6 pA), with rise and fall times of 278 µs and 283 µs for the response rate, respectively. Our findings provide a promising method for wide-spectrum detection and enrich the diversity of room-temperature photoelectric detection.
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At present, phenolic acid derivatives and triazole derivatives have a good antifungal effect, which has attracted widespread attention. A series of novel phenolic acid triazole derivatives were synthesized, and their structures were characterized by IR, MS, NMR, and X-ray crystal diffraction. Compound methyl 4-(2-bromoethoxy)benzoate, methyl 4-(2-(1H-1,2,4-triazol-1-yl) ethoxy)benzoate, 4-(2-(1H-1,2,4-triazol-1-yl)ethoxy)benzoic acid and 4-(2-(1H-1,2,4-triazol-1-yl) ethoxy)-3-methoxybenzoic acid crystallize in the monoclinic system with space group P21/n, the monoclinic system with space group P21, the monoclinic system with space group P21 and the orthorhombic system with space group Pca21, respectively. At a concentration of 100 µg/mL and 200 µg/mL, the antifungal activity against seven plant pathogen fungi was determined. Compound methyl 4-(2-bromoethoxy)benzoate has the best inhibitory effect on Rhizoctonia solani AG1, and the inhibitory rate reached 88.6% at 200 µg/mL. The inhibitory rates of compound methyl 4-(2-(1H-1,2,4-triazol-1-yl) ethoxy)benzoate against Fusarium moniliforme and Sphaeropsis sapinea at a concentration of 200 µg/mL were 76.1% and 75.4%, respectively, which were better than that of carbendazim.
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Bladder cancer is a common malignant tumor of the urinary system.The prognosis of patients with positive lymph nodes is worse than that of patients with negative lymph nodes.An accurate assessment of preoperative lymph node statushelps to make treatmentdecisions,such as the extent of pelvic lymphadenectomy and the use of neoadjuvant chemotherapy.Imaging examination and pathological examination are the primary methods used to assess the lymph node status of bladder cancer patients before surgery.However,these methods have low sensitivity and may lead to inaccuate staging of patients.We reviewed the research progress and made an outlook on the application of clinical diagnosis,imaging techniques,radiomics,and genomics in the preoperative evaluation of lymph node metastasis in bladder cancer patients at different stages.
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Cistectomía , Neoplasias de la Vejiga Urinaria , Humanos , Metástasis Linfática , Estadificación de Neoplasias , Cistectomía/métodos , Neoplasias de la Vejiga Urinaria/patología , Escisión del Ganglio Linfático/métodos , Ganglios Linfáticos/patologíaRESUMEN
Mn2+ doped colloidal three-dimensional (3D) lead halide perovskite nanocrystal (PNC) has attracted intensive research attention; however, the low exciton binding energy and fatal optical instability of 3D PNC seriously hinder the optoelectronic application. Therefore, it remains significant to explore new stable host perovskite with strongly bound exciton to realize more desirable luminescent property. In this work, we utilized bulk one-dimensional (1D) hybrid perovskite of [AEP]PbBr5 â H2 O (AEP=N-aminoethylpiperazine) as structural platform to rationally optimize the luminescent property by a controllable Mn2+ doping strategy. Significantly, the series of Mn2+ -doped 1D [AEP]PbBr5 â H2 O show enhanced energy transfer efficiency from the strongly bound excitons of host material to 3d electrons of Mn2+ ions, resulting in tunable broadband light emissions from weak yellow to strong red spectral range with highest photoluminescence quantum yield up to 28.41 %. More importantly, these Mn2+ -doped 1D perovskites display ultrahigh structural and optical stabilities in humid atmosphere, water and high temperature exceeding the conventional 3D PNC. Combined highly efficient, tunable and stable broadband light emissions enable Mn2+ -doped 1D perovskite as excellent down-converting phosphor showcasing the potential application in white light emitting diode. This work not only provides a profound understanding of low-dimensional perovskites but also opens a new way to rationally design high-performance broadband light emitting perovskites for solid-state lighting and displaying devices.
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A variety of functionalized sulfonium ylides were prepared in good yields through MnSO4-promoted S-O bond cleavage from activated alkynes and sulfoxides. Experimental results showed that the MnSO4 catalyst played important roles in accelerating the reaction and promoting the [1,3]-rearrangement of the S-O bond. Furthermore, the product was easily obtained on a gram scale by simple recrystallization without column chromatography. The obtained product can be converted to new sulfonium ylides and undergo cycloaddition with an alkyne to afford a trisubstituted furan scaffold.
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An easily prepared fluoro-functionalized ionic covalent organic framework (F-iCOF) has been implemented into MALDI-TOF MS, enabling the highly selective enrichment and sensitive determination of perfluorinated sulfonate (PFS) contaminants in a rapid and convenient manner. The good thermal stability and excellent optical absorption properties of F-iCOF makes it a brilliant matrix with no background noise. Moreover, benefitting from the large surface area, appropriate pore size, good water dispersibility, and abundant fluorine atom and cationic characteristic of F-iCOF, it exhibited superior adsorption capacity and enrichment selectivity towards PFSs. Good signal responses for PFSs were obtained in the presence of various interfering compounds such as BSA, HA, or even more than 100-fold excess of glutamic acid and similar in structure sodium alkyl sulfonates, highlighting the specific selectivity of F-iCOF. Calibration curves for potassium perflurobutane sulfonate (PFBSK) in tap water and whole blood were established with good linear correlation in the range 1-500 pg mL-1. The limits of detection and quantification for PFBSK were as low as 0.04 pg mL-1 and 0.05 pg mL-1, respectively, which are comparable or better than the existing methods for the determination of PFSs.
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Estructuras Metalorgánicas , Estructuras Metalorgánicas/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Adsorción , Iones , Alcanosulfonatos , Agua/químicaRESUMEN
Decarboxylation strategy has been emerging as a powerful tool for the synthesis of fluorine-containing organic compounds that play important roles in various fields such as pharmaceuticals, agrochemicals, and materials science. Considerable progress in decarboxylation has been made over the past decade towards the construction of diverse valuable fluorinated fine chemicals for which the fluorinated part can be brought in two ways. The first way is described as the reaction of non-fluorinated carboxylic acids (and their derivatives) with fluorinating reagents, as well as fluorine-containing building blocks. The second way is dedicated to the exploration and the use of fluorine-containing carboxylic acids (and their derivatives) in decarboxylative transformations. This review aims to provide a comprehensive summary of the development and applications of decarboxylative radical, nucleophilic and cross-coupling strategies in organofluorine chemistry.
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Research has explored age-related and cultural differences in moral evaluations of dishonesty; however, this has not yet been examined in an aging context. The present study provided a novel account of how younger and older adults (in Canada, Singapore, and China; N = 401) morally evaluate adults' truths and lies in antisocial, modesty, and politeness settings. Participants completed a questionnaire assessing how acceptable it is for adults to tell the truth or a lie in given social scenarios, and they reported on their levels of collectivism and individualism. In all countries, older adults provided more favorable evaluations to blunt and immodest truths than younger adults did. Compared with younger adults, older adults provided harsher evaluations to Polite Lies (in Canada and China) and Modesty Lies (in Canada and Singapore). Thus, there may be an age-related increase in the acceptability of direct honesty over good-intentioned lies, and this age effect is somewhat stable across cultures. Older adults were also more lenient in evaluations of an antisocial lie to conceal an affair compared to younger adults. Overall, adults in China tended to rate lies less negatively, and their greater levels of collectivism mediated their greater approval of polite lies. The present results demonstrate that evaluations of (dis)honesty differ as a function of age and culture and these results can assist in developing a more complete lifespan model of the morality of dishonesty. Supplementary Information: The online version contains supplementary material available at 10.1007/s12144-022-03785-6.
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Low-dimensional organic-inorganic hybrid metal halide materials have been extensively studied due to their excellent optoelectronic performances. Herein, by using the facile wet-chemistry method, we designed one new hybrid cadmium bromide of (H3AEP)2CdBr6·2Br based on discrete octahedral [CdBr6]4- units. Remarkably, the bulk crystal of (H3AEP)2CdBr6·2Br exhibits strong broadband orange-red light emission from the radiative recombination of self-trapped excitons (STEs) with a high photoluminescence quantum yield (PLQY) of 9%. Benefiting from the highly efficient luminescent performance, this 0D cadmium perovskite can be utilized as an excellent down-conversion red phosphor to assemble a white light-emitting diode, and a high color rendering index (CRI) of 93 is realized. As far as we know, this is the first orange-red light-emitting hybrid cadmium perovskite which promotes the full-color display in this system.
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Palladium-catalyzed aerobic oxidative cyclizations of substituted 2-(1H-pyrrol-1-yl)phenols with isocyanides via an O-H/C-H insertion cascade have been developed. This strategy provides facile access to pyrrolo[2,1-c][1,4]benzoxazine derivatives in good to excellent yields under an O2 atmosphere. The notable features of this protocol include its mild reaction conditions, atom-economy, and broad functional group tolerance.
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Scientific research on how children learn to tell lies has existed for more than a century. Earlier studies mainly focused on moral, social, and situational factors contributing to the development of lying. Researchers have only begun to explore the cognitive correlations of children's lying in the last two decades. Cognitive theories suggest that theory of mind (ToM) and executive function (EF) should be closely related to the development of lying since lying is, in essence, ToM and EF in action. Yet, findings from empirical studies are mixed. To address this issue, the current meta-analysis reviewed all prior literature that examined the relations between children's lying and ToM and/or between children's lying and EF. In total, 47 papers consisting of 5099 participants between 2 and 19 years of age were included, which yielded 74 effect sizes for ToM and 94 effect sizes for EF. Statistically significant but relatively small effects were found between children's lying and ToM (r = .17) and between lying and EF (r = .13). Furthermore, EF's correlation with children's initial lies was significantly smaller than its correlation with children's ability to maintain lies. This comprehensive meta-analysis provides a clear picture of the associations between children's ToM/EF and their lying behavior and confirms that ToM and EF indeed play a positive role in children's lying and its development.
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Función Ejecutiva , Teoría de la Mente , Niño , Desarrollo Infantil , Humanos , Principios MoralesRESUMEN
Previous studies showed that the cortical reward system plays an important role in deceptive behavior. However, how the reward system activates during the whole course of dishonest behavior and how it affects dishonest decisions remain unclear. The current study investigated these questions. One hundred and two participants were included in the final analysis. They completed two tasks: monetary incentive delay (MID) task and an honesty task. The MID task served as the localizer task and the honesty task was used to measure participants' deceptive behaviors. Participants' spontaneous responses in the honesty task were categorized into three conditions: Correct-Truth condition (tell the truth after guessing correctly), Incorrect-Truth condition (tell the truth after guessing incorrectly), and Incorrect-Lie condition (tell lies after guessing incorrectly). To reduce contamination from neighboring functional regions as well as to increase sensitivity to small effects (Powell et al., Devel Sci 21:e12595, 2018), we adopted the individual functional channel of interest (fCOI) approach to analyze the data. Specially, we identified the channels of interest in the MID task in individual participants and then applied them to the honesty task. The result suggested that the reward system showed different activation patterns during different phases: In the pre-decision phase, the reward system was activated with the winning of the reward. During the decision and feedback phase, the reward system was activated when people made the decisions to be dishonest and when they evaluated the outcome of their decisions. Furthermore, the result showed that neural activity of the reward system toward the outcome of their decision was related to subsequent dishonest behaviors. Thus, the present study confirmed the important role of the reward system in deception. These results can also shed light on how one could use neuroimaging techniques to perform lie-detection.
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Mapeo Encefálico , Espectroscopía Infrarroja Corta , Decepción , Humanos , Motivación , RecompensaRESUMEN
Understanding the interactions between planar defects and complex dislocation structures in a material is of great significance to simplify its design. In this paper, we show that, from an atomistic perspective, by using molecular dynamics simulations on nanoindentations, a prismatic dislocation loop in Ni3Al appears in pairs with a butterfly-like shape. The planar defects in Ni3Al can effectively block the movement of the prismatic dislocation loop pairs and play a hardening role. Among the impediment factors, twinning boundaries are the strongest and antiphase boundaries are the weakest. Superlattice intrinsic and complex stacking faults have basically the same blocking effect. Furthermore, we systematically elucidate the hardening effects and interaction mechanisms between the prismatic dislocation loop pairs and planar defects. These findings provide novel insights into the nanostructured design of materials with excellent mechanical properties.
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To fully participate in the human information-sharing ecosystem that allows for efficient knowledge dissemination and creation, children need to be able to teach others effectively. The current research is the first to investigate links between children's teaching abilities and their developing theory of mind abilities in a non-Western sample. In a sample of 4- to 6-year-old Singaporean children (N = 49), we examined relations between specific components of theory of mind abilities and teaching ability on a social cognitive task. We found that both false belief understanding and the ability to make mental state inferences in a teaching context were associated with effective teaching even after controlling for age and language ability. These findings provide a nuanced picture of the links between mental state reasoning and teaching ability. More broadly, they provide evidence that these links extend beyond Western cultures and generalize to social-cognitive teaching contexts.