Publications by authors named "Tang Shiming"

Hubel and Wiesel's ice-cube model proposed that V1 orientation and ocular dominance functional maps intersect orthogonally to optimize wiring efficiency. Here, we revisited this model and additional arrangements at both cellular and pixel levels in awake macaques using two-photon calcium imaging. The recorded response fields of view were similar in size to hypercolumns, each containing up to 2,000 identified neurons and representing full periods of orientation preferences and ocular dominance.

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Hydroxytyrosol has been proven beneficial to human health. However, the process involving the conversion of L-DOPA to 3,4-dihydroxyphenylacetaldehyde (3,4-DHPAA) in hydroxytyrosol biosynthesis typically required the simultaneous use of decarboxylase and oxidative deaminase. In addition, phenylacetaldehyde reductase from Solanum lycopersicum (SlPAR) in hydroxytyrosol biosynthesis exhibits poor thermal stability.

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Laccases are extensively used in the textile industry due to their ability to decolorize dyes, modify fabric surfaces, and bleach textiles. Identifying a laccase with both high thermal stability and alkali tolerance suitable for textile applications presents a significant challenge. A novel alkaline laccase, LacCT, was discovered from Caldalkalibacillus thermarum and successfully expressed it in Escherichia coli.

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Biological visual systems have evolved to process natural scenes. A full understanding of visual cortical functions requires a comprehensive characterization of how neuronal populations in each visual area encode natural scenes. Here, we utilized widefield calcium imaging to record V4 cortical response to tens of thousands of natural images in male macaques.

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Object recognition often involves the brain segregating objects from their surroundings. Neurophysiological studies of figure-ground texture segregation have yielded inconsistent results, particularly on whether V1 neurons can perform figure-ground texture segregation or just detect texture borders. To address this issue from a population perspective, we utilized two-photon calcium imaging to simultaneously record the responses of large samples of V1 and V4 neurons to figure-ground texture stimuli in awake, fixating macaques.

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There are various types of land use in the agricultural and pastoral areas of northern China, including natural grassland and artificial grassland, scrub land, forest land and farmland, may change the soil microbial community However, the soil microbial communities in these different land use types remain poorly understood. In this study, we compared soil microbial communities in these five land use types within the agro-pastoral ecotone of northern China. Our results showed that land use has had a considerable impact on soil bacterial and fungal community structures.

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Primates rely on two eyes to perceive depth, while maintaining stable vision when either one eye or both eyes are open. Although psychophysical and modeling studies have investigated how monocular signals are combined to form binocular vision, the underlying neuronal mechanisms, particularly in V1 where most neurons exhibit binocularity with varying eye preferences, remain poorly understood. Here, we used two-photon calcium imaging to compare the monocular and binocular responses of thousands of simultaneously recorded V1 superficial-layer neurons in three awake macaques.

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Grazing causes great disturbances in grassland ecosystems and may change the abundance, diversity, and ecological function of soil biota. Because of their important role in nutrient cycling and as good environmental indicators, nematodes are very representative soil organisms. However, the mechanisms by which grazing intensity, livestock type, duration, and environmental factors (e.

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Although soil microbial biomass responses to experimental warming have been extensively studied, the mechanisms through which elevated temperatures influence soil microbial biomass remain unclear. In this study, we performed a global meta-analysis to quantify the global pattern of soil microbial biomass in response to warming. Our findings suggest that global warming effect is not apparent when all the data are pooled together, while warming does increase microbial biomass under specific conditions (Δ°C ≥ 2 °C).

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Background: The relationship between chronotype and anxiety, depression, and insomnia was inconsistent. We aimed to assess the association between chronotype and mental health and the potential moderating effect of age and socioeconomic status (SES).

Methods: A multi-stage sampling cross-sectional study with 12,544 adults was conducted.

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Multiple global change drivers typically co-occur in terrestrial ecosystems, usually with complex interactions on ecosystem carbon fluxes. However, how they interactively impact terrestrial carbon sinks remains unknown. Here, we synthesized 82 field experiments that studied the individual and pairwise effects among nitrogen addition (N), increased precipitation (IP), elevated CO (eCO) and warming, with direct measurements of net ecosystem productivity (NEP), gross ecosystem productivity (GEP) and ecosystem respiration (ER).

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Grazing disturbance can change the structure of plant rhizosphere microbial communities and thereby alter the feedback to promote plant growth or induce plant defenses. However, little is known about how such changes occur and vary under different grazing pressures or the roles of root metabolites in altering the composition of rhizosphere microbial communities. In this study, the effects of different grazing pressures on the composition of microbial communities were investigated, and the mechanisms by which different grazing pressures changed rhizosphere microbiomes were explored with metabolomics.

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Nitrogen enrichment and land use are known to influence various ecosystems, but how these anthropogenic changes influence community and ecosystem responses to disturbance remains poorly understood. Here we investigated the effects of increased nitrogen input and mowing on the resistance and recovery of temperate semiarid grassland experiencing a three-year drought. Nitrogen addition increased grassland biomass recovery but decreased structural recovery after drought, whereas annual mowing increased grassland biomass recovery and structural recovery but reduced structural resistance to drought.

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Article Synopsis
  • Grazing significantly affects grassland plant reproductive traits, leading to an increase in the number of tillers and vegetative branches but a decrease in the number of flowers and reproductive branches, especially in grasses.
  • Grazing encourages plants to shift from sexual to asexual reproduction, particularly under varying conditions of grazing intensity, precipitation, and duration.
  • This meta-analysis of 114 studies highlights the need for sustainable grazing management strategies to support both human needs and ecosystem health.
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Pomelo peel, as a by-product of pomelo consumption, is rich in various fiber and functional compounds. The utilization of the valuable components found in pomelo peel may mitigate environmental concerns. In this study, pomelo peel rich in lignin and oxygen-containing functional groups was used to prepare pomelo peel biochar (PPB) via temperature-programmed pyrolysis at different temperatures (800 ℃ and 1000 ℃).

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Natural images comprise contours and boundaries defined by 1st-order luminance-modulated (LM) cues that are readily encoded by V1 neurons, and 2nd-order contrast-modulated (CM) cues that carry local, but not over-the-space, luminance changes. The neurophysiological foundations for CM processing remain unsolved. Here we used two-photon calcium imaging to demonstrate that V1 superficial-layer neurons respond to both LM and CM gratings in awake, fixating, macaques, with overall LM responses stronger than CM responses.

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Overgrazing directly and indirectly affects soil microorganisms, which can have feedback effects on plant growth. Little is known about the root metabolites plants produce and whether they recruit beneficial microbes in response to overgrazing. Here, we used the dominant grassland species Leymus chinensis to explore correlations between root metabolites and the rhizosphere microbiome shaped by long-term overgrazing, which was determined by using LC-MS technology and high-throughput sequencing.

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Images of visual scenes comprise essential features important for visual cognition of the brain. The complexity of visual features lies at different levels, from simple artificial patterns to natural images with different scenes. It has been a focus of using stimulus images to predict neural responses.

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Motivation: Microscopic images are widely used in basic biomedical research, disease diagnosis and medical discovery. Obtaining high-quality in-focus microscopy images has been a cornerstone of the microscopy. However, images obtained by microscopes are often out-of-focus, resulting in poor performance in research and diagnosis.

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Humans perceive millions of colors along three dimensions of color space: hue, lightness, and chroma. A major gap in knowledge is where the brain represents these specific dimensions in cortex, and how they relate to each other. Previous studies have shown that brain areas V4 and the posterior inferotemporal cortex (PIT) are central to computing color dimensions.

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How the brain stores a sequence in memory remains largely unknown. We investigated the neural code underlying sequence working memory using two-photon calcium imaging to record thousands of neurons in the prefrontal cortex of macaque monkeys memorizing and then reproducing a sequence of locations after a delay. We discovered a regular geometrical organization: The high-dimensional neural state space during the delay could be decomposed into a sum of low-dimensional subspaces, each storing the spatial location at a given ordinal rank, which could be generalized to novel sequences and explain monkey behavior.

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The denitrification process profoundly affects soil nitrogen (N) availability and generates its byproduct, nitrous oxide, as a potent greenhouse gas. There are large uncertainties in predicting global denitrification because its controlling factors remain elusive. In this study, we compiled 4301 observations of denitrification rates across a variety of terrestrial ecosystems from 214 papers published in the literature.

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System identification techniques-projection pursuit regression models (PPRs) and convolutional neural networks (CNNs)-provide state-of-the-art performance in predicting visual cortical neurons' responses to arbitrary input stimuli. However, the constituent kernels recovered by these methods are often noisy and lack coherent structure, making it difficult to understand the underlying component features of a neuron's receptive field. In this paper, we show that using a dictionary of diverse kernels with complex shapes learned from natural scenes based on efficient coding theory, as the front-end for PPRs and CNNs can improve their performance in neuronal response prediction as well as algorithmic data efficiency and convergence speed.

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The modification of intracellular metabolic pathways by metabolic engineering has generated many engineered strains with relatively high yields of various target products in the past few decades. However, the unpredictable accumulation of toxic products, the cell membrane barrier, and competition between the carbon flux of cell growth and product synthesis have severely retarded progress toward the industrial-scale production of many essential chemicals. On the basis of an in-depth understanding of intracellular metabolic pathways, scientists intend to explore more sustainable methods and construct a cell-free biosynthesis system in vitro.

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