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18 June 2024, Volume 41 Issue 3 Previous Issue   
Research status and development trends of bioleaching technology
YANG Baojun, LIU Yang, LIU Hongchang, LI Yongmei, GAN Min, WANG Jun, LIAO Rui, ZHANG Ke, ZHU Zhenyu, QIU Guanzhou
2024, 41 (3):  1.  doi: 10.3969/j.issn.2095-1736.2024.03.001
Abstract ( 70 )   PDF  
The development and the utilization of low-grade mineral resources constrain global green and sustainable development. Bioleaching technology is a cutting-edge technology for achieving green and sustainable development in mineral processing and non-ferrous metal metallurgy and plays an important role inin-situremediation of heavy metal pollution sites in mines. This article reviewed the basic concepts, microbial physiological characteristics, and mechanisms of action of biotechnology, as well as the application and research status of biotechnology in copper ore extraction, refractory gold ore oxidation pretreatment, uranium ore extraction, and rare earth extraction. In the future, research should be conducted on the selection of high-efficiency leaching microorganisms, the interface mechanism of bioleaching, high-efficiency energy-saving devices, and engineering technologies, and further expanding the application fields of bioleaching technology.
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Comparative study on interactions between Myxococcus xanthus/Pseudomonas aeruginosa and ionic rare earth minerals #br#
WANG Mengyuan, HUANG Shiyun, LIU Hongchang, LIU Yang, LI Jingna, NIE Zhenyuan, XIA Jinlan, WANG Jun
2024, 41 (3):  11.  doi: 10.3969/j.issn.2095-1736.2024.03.011
Abstract ( 48 )   PDF  
In this paper,Myxococcus xanthusandPseudomonas aeruginosa, which are common in the rare earth mining environment, were prepared, and the solution behaviors of the two bacteria and their fermentation broth during the interaction with ion-type rare earth ore were comparatively studied. The morphology, structure, distribution of rare earth elements and functional groups of the cells and mineral phases were analyzed by means of scanning electron microscopy, transmission electron microscopy, X-ray diffraction and Fourier infrared spectroscopy. The results showed that there were some differences in the interaction processes of theM. xanthusandP. aeruginosaon rare earth minerals. In the leaching process of rare earth minerals, the direct-action system ofP. aeruginosawas better than that of the indirect-action system of the fermentation broth, while the direct-action system of theM. xanthuswas weaker than that of the indirect action system of the fermentation liquid. In addition, the presence of rare earth minerals can promote the secretion of lipid and protein components ofM. xanthusand inhibit the secretion of polysaccharide components, while forP. aeruginosa, the presence of rare earth minerals has little effect on the secretion of lipid and protein components but promotes the secretion of polysaccharide components.
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Study on the effect of different proportions of pyrite on the interaction between acidophilic microorganisms and stibnite
WANG Yirong, CHEN Lu, LIU Hongchang, ZHOU Yuhang, NIE Zhenyuan, CHEN Yuxin, CHEN Hao, XIA Jinlan
2024, 41 (3):  21.  doi: 10.3969/j.issn.2095-1736.2024.03.021
Abstract ( 37 )   PDF  
This study focused on the acidophilic microbial dissolution process of stibnite and investigated the effect of different proportions of pyrite on the interaction between acidophilic microorganisms and stibnite. The results showed that the Proteobacteria had the highest abundance at the phylum level, it was the main stibnite-tolerant bacterium.Acidithiobacillushad the highest level of abundance at the genus level, which was the representative dominant genus in acid mine environments. Additionally, SEM-EDS results showed that for microbial action systems with Sb2S3∶FeS21∶1 and 1∶2 , more corrosion pits and fine particles were found on the surface of mineral residues, and for the microbial action system with Sb2S3∶FeS21∶1, the interfacial reaction between stibnite and pyrite was stronger. XRD and XPS results indicated that the addition of pyrite could promote the oxidative decomposition of stibnite and sulfur oxidation by acidophilic microorganisms. Tafel polarization curves and EIS impedance results showed that when Sb2S3∶FeS2was 1∶1, the microbial system had the highest corrosion current density and the smallest charge-transfer impedance. The above results were of great significance for understanding the migration, transformation, and environmental fate of stibnite in antimony mining areas, and further promoting the development of antimony pollution control technologies.
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Study on arsenic tolerance of moderately thermophilic bacteria Leptospirillum ferrooxidans and Acidithiobacillus caldus
CHEN Yanzhen, ZHANG Guangji, GUO Jiale, YANG Chao
2024, 41 (3):  34.  doi: 10.3969/j.issn.2095-1736.2024.03.034
Abstract ( 42 )   PDF  
In this study, two moderately thermophilic bacteria, includingL. ferrooxidans(Leptospirillum ferrooxidans) andA. caldus(Acidithiobacillus caldus), used in bioleaching processes of refractory gold ores were taken as the main research objects. The effects of valence of arsenic (As(Ⅲ) and As(Ⅴ)) on the bio-oxidation of two moderately thermophilic bacteria were investigated through studied by shake flask experiment. The results were compared with two mesophilic bacteria,A. ferrooxidans(Acidithiobacillus ferrooxidans) andT. thiooxidans(Thiobacillus thiooxidans). The results showed that the tolerance to As(Ⅲ) of moderately thermophilic bacteria was significantly weaker than that of mesophilic bacteria, but both of thermophilic and mesophilic bacteria showed similar tolerance to As(Ⅴ). At the same time, the effect of As(Ⅲ) on iron-oxidizing bacteria in growth was greater than that on sulfur-oxidizing bacteria. It was found that increasing the bacteria inoculation amount and domesticating bacteria was conducive to the adaptation of moderately thermophilic bacteria to arsenic toxicity. In the actual ore pulp system, increasing the inoculation amount could make moderately thermophilic bacteria finally to adapt to the high arsenic environment and obtain better ore bioleaching effect. The highest mass concentration can reach about 1.54 g/L, and the arsenic leaching rate can be up to 70% in only 10 days.
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Optimization of enhanced leaching copper with Acidithiobacillus thiooxidans from waste printed circuit boards using microwave #br#
LIU Qian, LI Ruyan, LI Xiang, MA Changwen, TIAN Zhen, LIU Wenwen
2024, 41 (3):  40.  doi: 10.3969/j.issn.2095-1736.2024.03.040
Abstract ( 30 )   PDF  
In order to improve the leaching copper efficiency, microwave was used to enhance the leaching system ofA. thiooxidans. Plackett-Burman and Box-Behnken methods were used to optimize the enhanced bioleaching condition. Firstly, the significant factors identified by Plackett-Burman method were microwave power, irradiation time and leaching time. Secondly, the central values of above-mentioned three factors of Box-Behnken test were identified by the steepest ascent experiment, which were microwave power of 340 W, irradiation time of 3.60 min and leaching time of 6.80 d. And then, the experimental conditions of bioleaching copper withA. thiooxidanswere optimized using Box-Behnken method. The research showed that the microwave power, leaching time, the interactions of microwave power and leaching time plus irradiation time and leaching time had the significant influence on the bioleaching copper, whereas the effect of irradiation time was not significant. The optimal experimental condition predicted by model was as follows: microwave power 336.10 W, irradiation time 3.59 min and leaching time 6.82 d, and the predicted optimal value was 75.69%. The adjusted optimal condition was microwave power 336 W, irradiation time 3.60 min and leaching time 6.80 d, the experimental value was 75.41%±0.76%, indicating a high agreement between the predicted and experimental values.
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Response surface methodology for optimization of process parameters for indirect bioleaching of valuable metals from copper and cobalt ores
TIAN Bingyang, LI Jingze, SHANG He, LIU Xue, GAO Wencheng, WEN Jiankang
2024, 41 (3):  46.  doi: 10.3969/j.issn.2095-1736.2024.03.046
Abstract ( 31 )   PDF  
在生物浸出铜钴矿的基础上,采用生物活性沥浸液为浸出剂和响应面法优化浸出工艺参数以实现铜钴矿的高效生物浸出。菌液体系包含氧化硫硫杆菌,氧化亚铁硫杆菌和嗜铁钩端螺旋菌的混合体系。经30组实验结果统计分析发现,显著影响铜钴矿中Cu和Co浸出的因素为温度、固液比、初始pH、转速,以及温度-固液比、固液比-初始pH、固液比2和初始pH2的交互影响,而显著影响Fe浸出的因素为温度、固液比、初始pH和固液比2的交互影响。此外,针对生物浸出铜钴矿中Cu、Co和Fe浸出率的3个预测模型R2分别为0.9864、0.9687和0.9381,表明预测模型具有较高真实性。最终,铜钴矿的最优生物浸出参数为温度47.08 ℃、固液比1.17%、初始pH 0.81、转速120 r/min。在优化条件下,预测值分别为Cu 99.36%、Co 91.87%、Fe 88.43%,浸出24 h后实测值分别为100%、96.53%、86.11%。
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砷黄铁矿生物氧化影响因素及控制方法
HONG Maoxin, LIU Yuling, YANG Baojun, WANG Jun
2024, 41 (3):  52.  doi: 10.3969/j.issn.2095-1736.2024.03.052
Abstract ( 38 )   PDF  
Bio-oxidation of arsenopyrite is a major contributor to the generation of arsenic-containing acid mine drainage. This paper summarized the research status of key influencing factors and source control technologies related to arsenopyrite bio-oxidation. The physical and chemical properties, as well as the chemical and biological oxidation processes, of arsenopyrite were introduced. Detailed explanations were provided regarding the impact and mechanisms of environmental factors, such as microorganisms, co-existing ions, organic matters, and associated minerals, on arsenopyrite bio-oxidation. The oxidation of arsenopyrite and the release of arsenic into the environment are predominantly driven by water, oxygen, and microorganisms. The process can be inhibited by isolating any of these components, thereby preventing the formation of acid mine drainage. Consequently, the advantages and disadvantages of present source control methods such as oxygen barriers, bactericides, co-disposal, and passivation were analyzed and compared. Besides, potential research directions in this field were also outlined, providing a theoretical foundation for evaluating and mitigating arsenic-containing acid mine drainage caused by arsenopyrite bio-oxidation.
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Research progress on bioleaching of yttrium from rare earths #br#
YAN Linlin, WANG Hailan, XIAO Chunqiao, FANG Yun
2024, 41 (3):  61.  doi: 10.3969/j.issn.2095-1736.2024.03.061
Abstract ( 29 )   PDF  
The occurrence and distribution of rare earth yttrium (Y) in nature, the main chemical extraction and biological extraction methods were reviewed, and the relationship between rare earth yttrium and microorganisms was discussed from the aspects of rare earth yttrium bioleaching (microbial adsorption, microbial metabolite leaching) and the effect of rare earth yttrium on microorganisms. The biological extraction of rare earth yttrium has broad prospects, but it still faces many problems, such as the lack of dominant leaching strains and the unclear mechanism of mineral-microbial interaction. On this basis, this paper further put forward some suggestions, such as establishing a high-throughput microbial screening method and rapid identification of functional strains, strengthening the interaction mechanism between microorganisms and yttrium at the molecular level and the selective leaching of yttrium by microorganisms, popularizing the biological leaching of microbial metabolites, and optimizing the in-situ extraction technology, hoping to provide reference for the design and development of yttrium resources in China.
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Research progress and application in biomineralization of acidophilic iron-oxidizing bacteria
ZHOU Yi, WANG Jun, LIU Yang, YANG Baojun, WU Baiqiang, LI Huiying, LIU Hongchang, YU Shichao, LIU Shitong, LIAO Rui
2024, 41 (3):  69.  doi: 10.3969/j.issn.2095-1736.2024.03.069
Abstract ( 25 )   PDF  
This article focused on the research progress on intracellular and extracellular mineralization of acidophilic iron-oxidizing bacteria. It summarized the properties of intracellular mineralization products of acidophilic iron-oxidizing bacteria and factors affecting the synthesis of mineralized products, and sorted the synthesis mechanism of magnetic nanoparticles at this stage. The synthesis principles and influencing factors of extracellular mineralization products of acidophilic iron-oxidizing bacteria were also summarized. Finally, the application prospects of mineralization products of acidophilic iron-oxidizing bacteria were introduced, and the shortcomings of current research on magnetic nanoparticles were pointed out. Based on the current research status, this article proposed new ideas for relying on molecular biology to analyze intracellular mineralization mechanisms and expand its application scope in the future. It was expected to provide theoretical guidance for further research on intracellular and extracellular mineralization of acidophilic iron-oxidizing bacteria and its applications.
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An initial exploration synergistic anti-aging effects and mechanisms of acetaminophen and N-acetylcysteine
JIANG Lixiang, HAN Qiong, DUAN Jiaxin, LI Han, CAO Qian, HUANG Xinhe
2024, 41 (3):  77.  doi: 10.3969/j.issn.2095-1736.2024.03.077
Abstract ( 33 )   PDF  
Drug synergy is a promising new anti-aging strategy. Construction of the aging model induced by D-galactose in HUVEC cells was aimed to explore the potential synergistic anti-aging effect of acetylsalicylic acid and acetylcysteine, and to investigate the underlying mechanisms of their synergy in anti-aging. Network pharmacology was used to screen a group of small molecules with potential anti-aging activity. D-galactose-induced HUVEC cells was employed to detect the anti-aging activity of small molecules, and Chou-Talalay model was used to screen two small molecule combinations with synergistic anti-aging effects. Further investigation of the mechanisms underlying the anti-aging activity mediated by the selected small molecule combinations was conducted using biochemical and cell biological approaches. Results showed that acetaminophen acid and acetylcysteine were a highly effective pair of small molecules with anti-aging activity, which could produce synergistic effects in mediating anti-aging. The synergistic combination significantly reduced intracellular reactive oxygen species levels, effectively relieved cell cycle arrest induced by D-galactose, and significantly reduced the transcription levels of early inflammatory factors (IL-1β, COX-2). In addition, the synergistic combination significantly reduced the protein levels of cell senescence markers (p53, p16), as well as p-p38 and nuclear p65 protein levels, indicating that the acetylsalicylic acid and N-acetylcysteine synergistic combination may inhibit cell aging via the MAPK/NF-κB pathway. These results provide a theoretical basis for the further development and utilization of acetylsalicylic acid and N-acetylcysteine as a synergistic anti-aging combination.
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β淀粉样蛋白寡聚体毒性环境下Bryostatin-1对神经突触活性的影响和潜在机制
PAN Wenyang, CHEN Peng, SUN Miao, BAO Xiaofeng
2024, 41 (3):  85.  doi: 10.3969/j.issn.2095-1736.2024.03.085
Abstract ( 34 )   PDF  
By using Western Blot, kinase activity assay, confocolmicroscopy, and electrophysiology recording methods, the synapse toxicity induced by Bryostatin-1 protects Aβ oligomers was studied and its potential mechanisms was investigated. Results showed that in the present of Aβ oligomers, Bryostatin-1 could significantly protect the morphology of dendritic spines, and promote the maturation of dendritic spines. Furthermore, electrophysiology recording result also showed that Aβ oligomers could inhibit mEPSC and Bryostatin-1 could rescue it. The AMPA/NMDA ratio did not change significantly among each group. Western Blot results also showed higher pre- and post-synaptic markers in the present of Bryostatin-1. The mechanisms underlying the protective effect of Bryostatin-1 was investigated. Western Blot results showed that Bryostatin-1 could activate mTOR-S6K1 signal pathway. At last, GFP-RFP-LC3 plasmid was transfected into primary hippocampus neuron culture. Confocolmicroscopy results showed that Aβ oligomers could inhibit the autophagic flux, and Bryostatin-1could promote the autophagic flux in the present of Aβ oligomers. In summary, the present study showed that Bryostatin-1 could activate mTOR-S6K1 signal pathway and then promote autophagic flux in the present of Aβ oligomers, which may be the mechanisms underlying the protective effect of PKC against Aβ oligomers induced synaptic toxicity.
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Utilization of proximity labeling-mass spectrometry technique to identify Ebola virus-associated host factor in Human
ZHANG Xun, BAI Yu, LIU Hainan, LIU Xuan, CAO Cheng
2024, 41 (3):  92.  doi: 10.3969/j.issn.2095-1736.2024.03.092
Abstract ( 30 )   PDF  
The fusion protein of VP35 and biotin ligase TurboID was generated, and the Ebola virus minigenome system (EBOV MG) was utilized to simulate the Ebola virus lifecycle and formation of virus inclusion bodies (VIB) in cells. The introduction of exogenous biotin enabled the labeling of proteins to interact with VP35. Among all proximity labeling (PL) labeled proteins, 537 potential VP35-associated host proteins were identified by differential abundance analysis after quantitative mass spectrometry detection. Gene Ontology (GO) analysis found that many enriched proteins were involved in RNA binding related functions. Subsequently, the association of EBOV VP35 with RNA binding proteins EIF4B and ZNF598 was confirmed. Interruption of EIF4B and ZNF598 expression significantly inhibited EBOV trVLP replication. The study highlighted the effectiveness of PL-quantitative mass spectrometry in identifying virus-host interaction proteins, providing a valuable tool for investigating viral pathogenesis and identifying potential antiviral targets.
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Construction and degradation kinetics of phenol-degrading mixed bacteria
YANG Zongzheng, LIU Weimeng, WU Zhiguo, ZHAO Wenli
2024, 41 (3):  98.  doi: 10.3969/j.issn.2095-1736.2024.03.098
Abstract ( 34 )   PDF  
To improve the degradation efficiency of phenol in wastewater, mixed bacteria were constructed by using the synergistic effects among three bacterial strains. The proportion of strains was optimized with orthogonal experiment. Then the mixed bacteria were adopted to degrade phenol with an initial mass concentration ranging from 400 to 1400 mg/L. Meanwhile, Three-half-order model was proposed for the first time to describe the degradation kinetic of phenol. The results showed that the mixed bacteria with optimized composition and proportion were able to increase the degradation efficiency of phenol to 99.85%. Compared with first order kinetic model, Three-half-order model with fitted parameters brought better prediction of the degradation kinetics of phenol. This study provides an insight into the biological degradation of phenol wastewater with mixed strains and its degradation kinetics.
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#br# Screening of a salt-tolerant PHE-degrading bacterium and its physiological response to salt stresses #br#
LI Wenjing, JI Lei, LI Tianyuan, XING Yingna, LI Qi, ZHANG Qiang, FU Xiaowen
2024, 41 (3):  103.  doi: 10.3969/j.issn.2095-1736.2024.03.103
Abstract ( 38 )   PDF  
Through the high-throughput screening technique, a highly effective phenanthrene-degrading bacterium was screened and isolated from the oil sludge of the Shengli Oilfield, China. By means of 16S rDNA sequencing, the strain was identified asPseudarthrobacter phenanthrenivoransand named as A-5. Physiological responses of strain A-5 were investigated in the face of different levels of salt stresses (with 0, 1%, 3%, 5% and 7% NaCl added, respectively). The results showed that the strain A-5 exhibited a high degradation capacity of phenanthrene under salinities of less than 3%, with a weekly degradation rate of 95.45%, 91.20% and 79.54%, respectively. However, when added NaCl above 5%, its degradation efficiency decreased significantly to 2.98% and 1.56%, respectively. The growth rate of strain A-5 was gradually inhibited with the increase of LB medium salinity. When the ambient salinity increased, contents of saturated fatty acids in cell membrane of strain A-5 decreased, while the contents of unsaturated fatty acids and the intracellular ectoine increased.
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Research progress of ubiquitination modification and its regulation of fruits responding to environmental stresses
SUN Wenwen, LYU Meng, GU Yefei, ZHANG Xinhua, LI Xiaoan, LI Fujun
2024, 41 (3):  109.  doi: 10.3969/j.issn.2095-1736.2024.03.109
Abstract ( 38 )   PDF  
The important regulation roles of a process called ubiquitination in fruits to withstand environmental stress conditions were introduced in this work. Moreover, the constituent of ubiquitination system, especial the E3 ubiquitin ligase and the 26S proteosome that can specially recognized and hydrolyze the target proteins, and their modification process were described. Based on these, this work focused on the regulation and possible mechanism of ubiquitination modification process, taking the E3 ubiquitin ligase as core. This modification process helps fruits respond to different stresses like drought, salt, cold, heavy metals, aging, and even attacks from pathogenic bacteria. Additionally, the study highlighted several unresolved questions concerning how ubiquitination alterations work in fruits, including the inadequacy of ubiquitination-related genes and enzymes function identification, the spatial and temporal control of ubiquitination modification and its deubiquitination, and the lack of means to identify the ubiquitination modification sites. Ultimately, this work aimed to provide valuable insights into how modifications in ubiquitination contribute to the fruit quality formation and maintenance.
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Study on the environmental DNA preservation conditions of fishes
LIU Yang, YING Fang, YANG Jun, WANG Huanying, HONG Wenjie, WANG Tingzhang
2024, 41 (3):  114.  doi: 10.3969/j.issn.2095-1736.2024.03.114
Abstract ( 28 )   PDF  
The optimal preservation method and preservation time for DNA from the simulated water samples of reared fish was studied. Water samples at the same volume were pretreated with 0.45 μm filter membranes inanucleic acid-free environment. Comparison of the obtained quality of eDNA, PCR concentrations of fish 12S rRNA gene, and the amplicon sequencing results based on the available amplicon sequence variant method by combination of different preservation method and preservation time were studied. The results showed that with six preservation methods (-20 ℃ freezing, -80 ℃ freezing, ethyl alcohol at room temperature, 75% ethanol at room temperature, Longmire buffer at room temperature, and TK buffer at room temperature), the TK buffer at room temperature was the best eDNA captured methods, followed by freezing (-20 ℃, -80 ℃). And the -20 ℃, -80 ℃, and TK buffer at room temperature had good stability under the same preservation time respectively, and could stably preserve the filter membrane within two weeks to maximize the genetic information of fish in water samples. This study provided technical reference for third-party gene detection laboratories for fish eDNA preservation strategies and facilitating the development of eDNA metabarcoding technology.
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Construction and application of virtual simulation experiment teaching center for biological science and technology
WANG Tian, ZHANG Dawei, LI Fosheng, XIONG Li, LIN Honghui
2024, 41 (3):  121.  doi: 10.3969/j.issn.2095-1736.2024.03.121
Abstract ( 44 )   PDF  
Through the transformation of excellent scientific research projects and cooperation with high-tech enterprises, Virtual Simulation Experiment Teaching Center for Biological Science and Technology built a batch of high-quality virtual simulation experiment teaching resources. The multi-level and diversified resources provide a favorable environment for students to learn frontier scientific knowledge, comprehensive scientific research training, and biological downstream industry technology training, at the same time,they realize the learning and extension of interdisciplinary knowledge, and reform the teaching modes effectively. The 24/7 open and shared virtual simulation experimental teaching platform achieves the organic integration of online teaching resources such as virtual simulation experimental teaching software, standardized experimental videos, teaching courseware and test question banks, meets the needs of experimental teaching anytime and anywhere, and supports a series of mixed online and offline experimental teaching courses. The center, in collaboration with National Demonstration Center for Experimental Biology Education, forms a "dual center" integrated development of innovative talent training experimental teaching system. The experimental teaching mode of "combining virtuality and reality" improves the comprehensive scientific research ability of students and the professional level of teachers, and cultivates the practical talents of biotechnology innovation to meet the needs of society.
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Research and practice on the multidimensional collaborative model for cultivating top innovative talents in biological sciences #br#
ZHOU Ling, HUANG Mingmin, HE Xiaoxiao, TU Haijun, XU Xianghui, GU Xuyang, WAN Muyang, CHEN Yan, GUO Xinhong
2024, 41 (3):  127.  doi: 10.3969/j.issn.2095-1736.2024.03.127
Abstract ( 30 )   PDF  
Cultivating top-notch innovative talents in life sciences is one of the important strategic measures of the country. In response to the problems in cultivating top-notch innovative talents in the field of biological sciences in universities, we actively explored the deep integration of biological science professional knowledge education and innovation and entrepreneurship education, as well as the reform, integration, and innovation of teaching resource organization forms and education models. We built excellent teachers, high-quality curriculum systems, and high-end education platforms, and constructed a “six in one” multi-dimensional collaborative cultivation model for top-notch innovative talents centered on curriculum guidance, integration of science and education, practical teaching, scientific research training, competition traction, and innovation platforms. We embarked on a path of talent cultivation that emphasized multi-dimensional collaboration and the pursuit of excellence. By promoting the implementation of this model, our university has achieved good results in cultivating top-notch innovative talents in the field of bioscience, which can provide a useful inspiration and reference for other universities at home and abroad.
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