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The development of new materials and their compositional and microstructural optimization are essential in regard to next-generation technologies such as clean energy and environmental sustainability. However, materials discovery and optimization have been a frustratingly slow process. The Edisonian trial-and-error process is time consuming and resource inefficient, particularly when contrasted with vast materials design spaces1. Whereas traditional combinatorial deposition methods can generate material libraries2,3, these suffer from limited material options and inability to leverage major breakthroughs in nanomaterial synthesis. Here we report a high-throughput combinatorial printing method capable of fabricating materials with compositional gradients at microscale spatial resolution. In situ mixing and printing in the aerosol phase allows instantaneous tuning of the mixing ratio of a broad range of materials on the fly, which is an important feature unobtainable in conventional multimaterials printing using feedstocks in liquid-liquid or solid-solid phases4-6. We demonstrate a variety of high-throughput printing strategies and applications in combinatorial doping, functional grading and chemical reaction, enabling materials exploration of doped chalcogenides and compositionally graded materials with gradient properties. The ability to combine the top-down design freedom of additive manufacturing with bottom-up control over local material compositions promises the development of compositionally complex materials inaccessible via conventional manufacturing approaches.
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The regulation of autophagy initiation is a key step in autophagosome biogenesis. However, our understanding of the molecular mechanisms underlying the stepwise assembly of ATG proteins during this process remains incomplete. The Rab GTPase Ypt1/Rab1 is recognized as an essential autophagy regulator. Here, we identify Atg23 and Atg17 as binding partners of Ypt1, with their direct interaction proving crucial for the stepwise assembly of autophagy initiation complexes. Disruption of Ypt1-Atg23 binding results in significantly reduced Atg9 interactions with Atg11, Atg13, and Atg17, thus preventing the recruitment of Atg9 vesicles to the phagophore assembly site (PAS). Likewise, Ypt1-Atg17 binding contributes to the PAS recruitment of Ypt1 and Atg1. Importantly, we found that Ypt1 is phosphorylated by TOR at the Ser174 residue. Converting this residue to alanine blocks Ypt1 phosphorylation by TOR and enhances autophagy. Conversely, the Ypt1S174D phosphorylation mimic impairs both PAS recruitment and activation of Atg1, thus inhibiting subsequent autophagy. Thus, we propose TOR-mediated Ypt1 as a multifunctional assembly factor that controls autophagy initiation via its regulation of the stepwise assembly of ATG proteins.
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Proteínas de Saccharomyces cerevisiae , Autofagia/fisiología , Proteínas Relacionadas con la Autofagia/metabolismo , Fagosomas/metabolismo , Fosforilación , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismoRESUMEN
CFAP58 is a testis-enriched gene that plays an important role in the sperm flagellogenesis of humans and mice. However, the effect of CFAP58 on bull semen quality and the underlying molecular mechanisms involved in spermatogenesis remain unknown. Here, we identified two single-nucleotide polymorphisms (rs110610797, A>G and rs133760846, G>T) and one indel (g.-1811_ g.-1810 ins147bp) in the promoter of CFAP58 that were significantly associated with semen quality of bulls, including sperm deformity rate and ejaculate volume. Moreover, by generating gene knockout mice, we found for the first time that the loss of Cfap58 not only causes severe defects in the sperm tail, but also affects the manchette structure, resulting in abnormal sperm head shaping. Cfap58 deficiency causes an increase in spermatozoa apoptosis. Further experiments confirmed that CFAP58 interacts with IFT88 and CCDC42. Moreover, it may be a transported cargo protein that plays a role in stabilizing other cargo proteins, such as CCDC42, in the intra-manchette transport/intra-flagellar transport pathway. Collectively, our findings reveal that CFAP58 is required for spermatogenesis and provide genetic markers for evaluating semen quality in cattle.
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Análisis de Semen , Semen , Humanos , Bovinos , Masculino , Animales , Ratones , Cabeza del Espermatozoide , Espermatozoides , Ratones NoqueadosRESUMEN
It has long been assumed that lifespan and healthspan correlate strongly, yet the two can be clearly dissociated1-6. Although there has been a global increase in human life expectancy, increasing longevity is rarely accompanied by an extended healthspan4,7. Thus, understanding the origin of healthy behaviours in old people remains an important and challenging task. Here we report a conserved epigenetic mechanism underlying healthy ageing. Through genome-wide RNA-interference-based screening of genes that regulate behavioural deterioration in ageing Caenorhabditis elegans, we identify 59 genes as potential modulators of the rate of age-related behavioural deterioration. Among these modulators, we found that a neuronal epigenetic reader, BAZ-2, and a neuronal histone 3 lysine 9 methyltransferase, SET-6, accelerate behavioural deterioration in C. elegans by reducing mitochondrial function, repressing the expression of nuclear-encoded mitochondrial proteins. This mechanism is conserved in cultured mouse neurons and human cells. Examination of human databases8,9 shows that expression of the human orthologues of these C. elegans regulators, BAZ2B and EHMT1, in the frontal cortex increases with age and correlates positively with the progression of Alzheimer's disease. Furthermore, ablation of Baz2b, the mouse orthologue of BAZ-2, attenuates age-dependent body-weight gain and prevents cognitive decline in ageing mice. Thus our genome-wide RNA-interference screen in C. elegans has unravelled conserved epigenetic negative regulators of ageing, suggesting possible ways to achieve healthy ageing.
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Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/genética , Epigénesis Genética , Envejecimiento Saludable/genética , N-Metiltransferasa de Histona-Lisina/metabolismo , Factores Generales de Transcripción/metabolismo , Envejecimiento/genética , Animales , Proteínas de Caenorhabditis elegans/genética , Cognición , Disfunción Cognitiva , N-Metiltransferasa de Histona-Lisina/deficiencia , N-Metiltransferasa de Histona-Lisina/genética , Histonas/química , Histonas/metabolismo , Humanos , Longevidad/genética , Lisina/metabolismo , Masculino , Memoria , Metilación , Ratones , Mitocondrias/metabolismo , Neuronas/metabolismo , Proteínas/genética , Interferencia de ARN , Aprendizaje Espacial , Factores Generales de Transcripción/deficiencia , Factores Generales de Transcripción/genéticaRESUMEN
Mec1 is a DNA damage sensor, which performs an essential role in the DNA damage response pathway and glucose starvation-induced autophagy. However, the functions of Mec1 in autophagy remain unclear. In response to glucose starvation, Mec1 forms puncta, which are recruited to mitochondria through the adaptor protein Ggc1. Here, we show that Mec1 puncta also contact the phagophore assembly site (PAS) via direct binding with Atg13. Functional analysis of the Atg13-Mec1 interaction revealed two previously unrecognized protein regions, the Mec1-Binding Region (MBR) on Atg13 and the Atg13-Binding Region (ABR) on Mec1, which mediate their mutual association under glucose starvation conditions. Disruption of the MBR or ABR impairs the recruitment of Mec1 puncta and Atg13 to the PAS, consequently blocking glucose starvation-induced autophagy. Additionally, the MBR and ABR regions are also crucial for DNA damage-induced autophagy. We thus propose that Mec1 regulates glucose starvation-induced autophagy by controlling Atg13 recruitment to the PAS.
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Proteínas de Saccharomyces cerevisiae , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas Quinasas/metabolismo , Glucosa/metabolismo , Autofagia/fisiología , Proteínas Relacionadas con la Autofagia/genética , Proteínas Relacionadas con la Autofagia/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismoRESUMEN
Tetrameric assembly of channel subunits in the endoplasmic reticulum (ER) is essential for surface expression and function of K+ channels, but the molecular mechanism underlying this process remains unclear. In this study, we found through genetic screening that ER-located J-domain-containing chaperone proteins (J-proteins) are critical for the biogenesis and physiological function of ether-a-go-go-related gene (ERG) K+ channels in both Caenorhabditis elegans and human cells. Human J-proteins DNAJB12 and DNAJB14 promoted tetrameric assembly of ERG (and Kv4.2) K+ channel subunits through a heat shock protein (HSP) 70-independent mechanism, whereas a mutated DNAJB12 that did not undergo oligomerization itself failed to assemble ERG channel subunits into tetramers in vitro and in C. elegans. Overexpressing DNAJB14 significantly rescued the defective function of human ether-a-go-go-related gene (hERG) mutant channels associated with long QT syndrome (LQTS), a condition that predisposes to life-threatening arrhythmia, by stabilizing the mutated proteins. Thus, chaperone proteins are required for subunit stability and assembly of K+ channels.
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Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Canal de Potasio ERG1/metabolismo , Retículo Endoplásmico/metabolismo , Proteínas del Choque Térmico HSP40/metabolismo , Proteínas del Choque Térmico HSP47/metabolismo , Canales de Potasio/metabolismo , Animales , Animales Modificados Genéticamente , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/química , Proteínas de Caenorhabditis elegans/genética , Línea Celular Tumoral , Canal de Potasio ERG1/química , Canal de Potasio ERG1/genética , Células HEK293 , Proteínas del Choque Térmico HSP40/química , Proteínas del Choque Térmico HSP40/genética , Proteínas del Choque Térmico HSP47/química , Proteínas del Choque Térmico HSP47/genética , Proteínas HSP70 de Choque Térmico/metabolismo , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Síndrome de QT Prolongado/genética , Síndrome de QT Prolongado/metabolismo , Potenciales de la Membrana , Chaperonas Moleculares , Mutación , Miocitos Cardíacos/metabolismo , Canales de Potasio/química , Canales de Potasio/genética , Multimerización de Proteína , Estabilidad Proteica , Estructura Cuaternaria de Proteína , Interferencia de ARN , Canales de Potasio Shal/genética , Canales de Potasio Shal/metabolismo , Factores de Tiempo , TransfecciónRESUMEN
The emplacement of large igneous provinces (LIPs) has been linked to catastrophic mass extinctions in Earth's history, but some LIPs are only associated with less severe oceanic anoxic events, and others have negligible environmental effects. Although it is widely accepted that massive magma outpouring can affect the environment through volatile degassing, it remains debated what controls the severity of environmental crises. Here, we demonstrate that the second-most-voluminous Phanerozoic LIP, the Kerguelen LIP, may have contributed to the early Aptian oceanic anoxic event 1a, a global event previously believed to have been caused by the Ontong Java LIP. Geochronological data show that the earliest eruptions of the Kerguelen LIP preceded the onset of oceanic anoxic event 1a by at least â¼5 million years. Analyses of CO2 abundances in melt inclusions combined with Monte Carlo simulations reveal that the volume and degassing rate of CO2 emissions from the Kerguelen LIP are an order of magnitude lower compared to LIPs that caused severe mass extinctions. We propose that the severity of volcanism-related environmental and biotic perturbations is positively correlated with the volume and rate of CO2 emissions. Our results highlight the significant importance of reducing and slowing down CO2 emission in preventing future disastrous environmental consequences.
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The advent of 3D printing has facilitated the rapid fabrication of microfluidic devices that are accessible and cost-effective. However, it remains a challenge to fabricate sophisticated microfluidic devices with integrated structural and functional components due to limited material options of existing printing methods and their stringent requirement on feedstock material properties. Here, a multi-materials multi-scale hybrid printing method that enables seamless integration of a broad range of structural and functional materials into complex devices is reported. A fully printed and assembly-free microfluidic biosensor with embedded fluidic channels and functionalized electrodes at sub-100 µm spatial resolution for the amperometric sensing of lactate in sweat is demonstrated. The sensors present a sensitive response with a limit of detection of 442 nm and a linear dynamic range of 1-10 mm, which are performance characteristics relevant to physiological levels of lactate in sweat. The versatile hybrid printing method offers a new pathway toward facile fabrication of next-generation integrated devices for broad applications in point-of-care health monitoring and sensing.
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Técnicas Biosensibles , Dispositivos Laboratorio en un Chip , Microfluídica , Técnicas Biosensibles/métodos , Impresión Tridimensional , LactatosRESUMEN
BACKGROUND: Chest CT scan is an effective way to detect and diagnose COVID-19 infection. However, features of COVID-19 infection in chest CT images are very complex and heterogeneous, which make segmentation of COVID-19 lesions from CT images quite challenging. OBJECTIVE: To overcome this challenge, this study proposes and tests an end-to-end deep learning method called dual attention fusion UNet (DAF-UNet). METHODS: The proposed DAF-UNet improves the typical UNet into an advanced architecture. The dense-connected convolution is adopted to replace the convolution operation. The mixture of average-pooling and max-pooling acts as the down-sampling in the encoder. Bridge-connected layers, including convolution, batch normalization, and leaky rectified linear unit (leaky ReLU) activation, serve as the skip connections between the encoder and decoder to bridge the semantic gap differences. A multiscale pyramid pooling module acts as the bottleneck to fit the features of COVID-19 lesion with complexity. Furthermore, dual attention feature (DAF) fusion containing channel and position attentions followed the improved UNet to learn the long-dependency contextual features of COVID-19 and further enhance the capacity of the proposed DAF-UNet. The proposed model is first pre-trained on the pseudo label dataset (generated by Inf-Net) containing many samples, then fine-tuned on the standard annotation dataset (provided by the Italian Society of Medical and Interventional Radiology) with high-quality but limited samples to improve performance of COVID-19 lesion segmentation on chest CT images. RESULTS: The Dice coefficient and Sensitivity are 0.778 and 0.798 respectively. The proposed DAF-UNet has higher scores than the popular models (Att-UNet, Dense-UNet, Inf-Net, COPLE-Net) tested using the same dataset as our model. CONCLUSION: The study demonstrates that the proposed DAF-UNet achieves superior performance for precisely segmenting COVID-19 lesions from chest CT scans compared with the state-of-the-art approaches. Thus, the DAF-UNet has promising potential for assisting COVID-19 disease screening and detection.
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COVID-19 , Humanos , COVID-19/diagnóstico por imagen , Tomografía Computarizada por Rayos XRESUMEN
[This corrects the article DOI: 10.1371/journal.ppat.1007484.].
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Metasurfaces have been widely studied for arbitrary manipulation of the amplitude, phase and polarization of a field at the sub-wavelength scale. However, realizing a high efficiency metasurface with simultaneous and independent control of the amplitude and phase in visible remains a challenge. In this work, an ultrathin single-cell dielectric metasurface which can modulate arbitrary complex amplitude in transmission mode is proposed. The amplitude is controlled by adjusting the dipoles and quadrupoles by tuning the geometric size, while the phase is manipulated based on the Pancharatnam-Berry phase by rotating the meta-atom. Complex amplitude fields for generating holographic images and structure light are utilized to verify the reliability of the proposed structure. It has been experimentally demonstrated that the quality of holographic image of complex-amplitude hologram encoded on the proposed metasurface is better than that of phase-only holograms and verified by simulation that complex structure light can be generated by the proposed structure. Our work expands the superior limits of various applications, including arbitrary beam shaping, 3D biological imaging, optical computing, and optics-on-chip devices.
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Metasurfaces are promising platforms for integrated compact optical systems. Traditional metasurface holography design algorithms are limited to information capacity due to finite spatial bandwidth production, which is insufficient for the growing demand for big data storage and encryption. Here, we propose and demonstrate deep learning empowered ultra-dense complex-amplitude holography using step-moving cascaded metasurfaces. Using deep learning artificial intelligence optimization strategy, the barriers of traditional algorithms can be conquered to meet diverse practical requirements. Two metasurfaces are cascaded to form the desired holography. One of them can move to switch the reconstruction images due to diffraction propagation accumulated during the cascaded path. The diffraction pattern from the first metasurface propagates at a different distance and meets with the second metasurface, reconstructing the target holographic reconstructions in the far-field. Such a technique can provide a new solution for multi-dimensional beam shaping, optical encryption, camouflage, integrated on-chip ultra-high-density storage, etc.
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Domestication and subsequent selection of cattle to form breeds and biological types that can adapt to different environments partitioned ancestral genetic diversity into distinct modern lineages. Genome-wide selection particularly for adaptation to extreme environments left detectable signatures genome-wide. We used high-density genotype data for 42 cattle breeds and identified the influence of Bos grunniens and Bos javanicus on the formation of Chinese indicine breeds that led to their divergence from India-origin zebu. We also found evidence for introgression, admixture, and migration in most of the Chinese breeds. Selection signature analyses between high-altitude (≥1800 m) and low-altitude adapted breeds (<1500 m) revealed candidate genes (ACSS2, ALDOC, EPAS1, EGLN1, NUCB2) and pathways that are putatively involved in hypoxia adaptation. Immunohistochemical, real-time PCR and CRISPR/cas9 ACSS2-knockout analyses suggest that the up-regulation of ACSS2 expression in the liver promotes the metabolic adaptation of cells to hypoxia via the hypoxia-inducible factor pathway. High altitude adaptation involved the introgression of alleles from high-altitude adapted yaks into Chinese Bos taurus taurus prior to their formation into recognized breeds and followed by selection. In addition to selection, adaptation to high altitude environments has been facilitated by admixture and introgression with locally adapted cattle populations.
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Altitud , Polimorfismo de Nucleótido Simple , Aclimatación/genética , Alelos , Animales , Bovinos/genética , Genotipo , Selección GenéticaRESUMEN
BACKGROUND: To reduce incision complications, minimally invasive operative approaches for treatment with acute Achilles tendon rupture have been developed, such as Mini-open repair and percutaneous repair. Which technique is the better surgical option? In the present study, we compared the two surgical procedures- modified Mini-open repair versus percutaneous repair-in the treatment of acute Achilles tendon rupture. METHODS: From January 2016 to November 2018, 68 matched patients with acute Achilles tendon rupture were divided into treatment group (Mini-open with modified Ma-Griffith technique) and control group (the Ma-Griffith technique). The patients were then treated with different surgical techniques and followed up for no less than 24 months, and the functional outcome scores and complications were retrospectively evaluated. RESULTS: The mean follow-up time in Mini-open repair group was 29.0±2.9 months, and that in control group was 27.9±2.9 months (P=0.147). The Mini-open repair group showed reliably higher American Orthopedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Score and Achilles tendon Total Rupture Score (ATRS) than the control group in functional assessment (95.0±3.8 vs. 92.3±5.3, P=0.000; 93.8±3.8 vs. 90.9±4.5,P=0.000). There was no cases of sural nerve injury in Mini-open repair group, whereas the percutaneous repair group had 5 cases of the same (P=0.027). No significant differences were found in the calf circumference (32.3±3.9 vs. 31.8±3.6) (P=0.564), range of motion of the ankle (51.3±4.8 vs. 50.5±4.2, P=0.362), or wound complications (34/0 vs. 34/0) (P=1.000) between the two groups at the end of the follow-up time. However, the percutaneous repair group had a shorter average operating time (23.1±5.2 min) than that of the Mini-open repair group (27.7±4.3 min) (P=0.000). CONCLUSIONS: Acute Achilles tendon ruptures may be treated successfully with a new Mini-open repair system or percutaneous repair technique. However, the Mini-open repair system may represent a superior surgical option, since it offers advantages in terms of direct visual control of the repair, AOFAS Ankle-Hindfoot Score, Achilles tendon Total Rupture Score and risk of sural nerve palsy. STUDY DESIGN: Case-control studies, Level of evidence, 3.
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Tendón Calcáneo , Procedimientos Ortopédicos , Tendón Calcáneo/cirugía , Humanos , Procedimientos Ortopédicos/efectos adversos , Estudios Retrospectivos , Rotura/cirugía , Resultado del TratamientoRESUMEN
BACKGROUND: Neutrophils are the first effectors of inflammatory response triggered by mastitis infection, and are important defense cells against pathogenic Escherichia coli (E. coli). DNA methylation, as a critical epigenetic mechanism for regulating gene function, is involved in bovine mastitis. RESULTS: In this study, we sequenced the blood neutrophils of healthy and E. coli-infected mastitic half-sib cows for the overall DNA methylation levels using transcriptome sequencing and reduced representation bisulfite sequencing. The methylation levels in the mastitis cows (MCs) were decreased compared with healthy cows (HCs). A total of 494 differentially methylated regions were identified, among which 61 were up-methylated and 433 were down-methylated (MCs vs. HCs). The expression levels of 1094 differentially expressed genes were up-regulated, and 245 genes were down-regulated. Twenty-nine genes were found in methylation and transcription data, among which seven genes' promoter methylation levels were negatively correlated with expression levels, and 11 genes were differentially methylated in the exon regions. The bisulfite sequencing PCR and quantitative real-time PCR validation results demonstrated that the promoter methylation of CITED2 and SLC40A1 genes affected differential expression. The methylation of LGR4 exon 5 regulated its own alternative splicing. The promoter methylation of bta-miR-15a has an indirect effect on the expression of its target gene CD163. The CITED2, SLC40A1, and LGR4 genes can be used as candidates for E. coli-induced mastitis resistance. CONCLUSIONS: This study explored the roles of DNA methylation in affecting transcription of protein-coding genes and miRNAs in E. coli-induced mastitis, thereby helping explain the function of DNA methylation in the pathogenesis of mastitis and provided new target genes and epigenetic markers for mastitis resistance breeding in dairy cattle.
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Metilación de ADN , Infecciones por Escherichia coli/veterinaria , Perfilación de la Expresión Génica/veterinaria , Mastitis Bovina/genética , Neutrófilos/química , Secuenciación Completa del Genoma/veterinaria , Animales , Estudios de Casos y Controles , Bovinos , Epigénesis Genética , Infecciones por Escherichia coli/genética , Femenino , Regulación de la Expresión Génica , Redes Reguladoras de Genes , Mastitis Bovina/microbiología , MicroARNs/genética , Regiones Promotoras Genéticas , Análisis de Secuencia de ARN/veterinariaRESUMEN
Abnormal metabolism and uncontrolled angiogenesis are two important characteristics of malignant tumors. The occurrence of both events involves many key molecular changes including miRNA. However, EBV encoded miRNAs are rarely mentioned as capable of regulating tumor metabolism and tumor angiogenesis. Here, we reported that one of the key miRNAs encoded by EBV, EBV-miR-Bart1-5P, can significantly promote nasopharyngeal carcinoma (NPC) cell glycolysis and induces angiogenesis in vitro and in vivo. Mechanistically, EBV-miR-Bart1-5P directly targets the α1 catalytic subunit of AMP-activated protein kinase (AMPKα1) and consequently regulates the AMPK/mTOR/HIF1 pathway which impelled NPC cell anomalous aerobic glycolysis and angiogenesis, ultimately leads to uncontrolled growth of NPC. Our findings provide new insights into metabolism and angiogenesis of NPC and new opportunities for the development of targeted NPC therapy in the future.
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Infecciones por Virus de Epstein-Barr , Glucólisis/genética , Carcinoma Nasofaríngeo/virología , Neovascularización Patológica/genética , ARN Viral , Transducción de Señal/fisiología , Adenilato Quinasa/metabolismo , Línea Celular Tumoral , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/metabolismo , Infecciones por Virus de Epstein-Barr/fisiopatología , Herpesvirus Humano 4 , Humanos , Factor 1 Inducible por Hipoxia/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Carcinoma Nasofaríngeo/metabolismo , Carcinoma Nasofaríngeo/patología , Fosfohidrolasa PTEN/metabolismo , ARN Viral/genética , ARN Viral/metabolismo , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
Herein, an efficient visible-light-mediated N-H heteroarylation via remote heteroaryl ipso-migration has been accomplished. Moderate to good yields were obtained with good functional group tolerance. Moreover, a simple and readily available organic photoredox catalyst was employed, avoiding the use of complex and costly noble metal compounds.
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Cowan, Donnell, and Saults [(2013). A list-length constraint on incidental item-to-item associations. Psychonomic Bulletin & Review, 20, 1253-1258] examined incidental memory of whether two words had occurred in the same list or different lists, after the lists had been presented with an orienting task that did not require memorisation. Performance was superior for 3-word lists compared to 6- or 9-word lists, with memory for the longer lists near chance levels. Here we re-examine this phenomenon with methodological modifications to ensure that learning was incidental: we removed potential clues that a memory test would follow, eliminated trials with special mnemonic cues related to the orienting task, eliminated participants who suspected a memory test according to a post-experimental questionnaire, used signal detection measures to distinguish between memory sensitivity and bias, and tested list length with the relative serial position controlled. Incidental memory formed primarily for the most recent part of each list, an effect that was stronger than that of list length. The new evidence helps to constrain theories about the relation between working memory and incidental learning. A capacity-limited approach to the incidental-learning process still is possible but must be modified compared to Cowan et al., and the evidence is favourable to other theoretical approaches as well.
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Memoria a Corto Plazo , Aprendizaje Seriado , Atención , Femenino , Humanos , MasculinoRESUMEN
Metal-organic framework cathodes usually exhibit low capacity and poor electrochemical performance for Li-ion storage owing to intrinsic low conductivity and inferior redox activity. Now a redox-active 2D copper-benzoquinoid (Cu-THQ) MOF has been synthesized by a simple solvothermal method. The abundant porosity and intrinsic redox character endow the 2D Cu-THQ MOF with promising electrochemical activity. Superior performance is achieved as a Li-ion battery cathode with a high reversible capacity (387â mA h g-1 ), large specific energy density (775â Wh kg-1 ), and good cycling stability. The reaction mechanism is unveiled by comprehensive spectroscopic techniques: a three-electron redox reaction per coordination unit and one-electron redox reaction per copper ion mechanism is demonstrated. This elucidatory understanding sheds new light on future rational design of high-performance MOF-based cathode materials for efficient energy storage and conversion.
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Complex-amplitude hologram can provide a high-quality image that is free of twin image and zero-order noise. Multi-SLMs methods, single SLM with space-division modulations and super pixel methods were striving to meet the requirements of complex amplitude modulation. In this work, we propose an ultra-thin dielectric metasurface to improve the quality of holographic image by loading complex amplitude hologram. This metasurface controls the amplitude and phase simultaneously and independently in transmission mode. The multipole expansion method is applied to analyze the mechanism. The polarization conversion efficiency can be up to 99% and the diffraction efficiency is 71%. The simulations verify that the quality of holographic image could be greatly improved by a complex-amplitude metasurface.