Research
·
2023
·
IF 11
Yaxin Chen,Rong Wang,Minbiao Ji
Jade is most valued in Chinese culture since ancient times. For unearthed jade artifacts, the alteration color resulting from weathering effects and human activities provides information for cultural heritage conservation, archaeology, and history. Currently, the noninvasive 3-dimensional characterization of jade artifacts with high chemical and spatial resolution remains challenging. In this work, we applied femtosecond pump–probe microscopy and second harmonic generation microscopy techniques to study the black alteration of an ancient jade artifact of the late Spring and Autumn period (546 to 476 BC). The direct cause of the “mercury alteration” phenomena was discovered to be the conversion of metacinnabar from buried cinnabar in the tomb. Furthermore, a 3-dimensional optical reconstruction of the black alteration was achieved, providing a high-resolution method for analyzing the blackening mechanism without the need of sample damage. Our approach opens up new opportunities to extract microscopic spatiochemical information for a broad range of alteration colors in jade artifacts.
研究领域:
考古学
·
材料科学
·
光学
✓ 已验证
DOI
高影响因子
NATURE METHODS
·
2025
·
IF 32.1
Cao Ruijie,Li Yaning,Zhou Yao,Li Meiqi,Lin Fangrui,Wang Wenyi,Zhang Guoxun,Wang Gang,Jin Boya,Ren Wei,Sun Yu,Zhao Zhifeng,Zhang Wei,Sun Jing,Hou Yiwei,Xu Xinzhu,Hu Jiakui,Shi Wei,Fu Shuang,Liang Qianxi,Lu Yanye,Li Changhui,Zhao Yuxuan,Li Yiming,Kuang Dong,Wu Jiamin,Fei Peng,Qu Junle,Xi Peng
In fluorescence microscopy, a persistent challenge is the defocused background that obscures cellular details and introduces artifacts. Here, we introduce Dark sectioning, a method inspired by natural image dehazing for removing backgrounds that leverages dark channel prior and dual frequency separation to provide single-frame optical sectioning. Unlike denoising or deconvolution, Dark sectioning specifically targets and removes out-of-focus backgrounds, stably improving the signal-to-background ratio by nearly 10 dB and structural similarity index measure of images by approximately tenfold. Dark sectioning was validated using wide-field, confocal, two/three-dimensional structured illumination and one/two-photon microscopy with high-fidelity reconstruction. We further demonstrate its potential to improve the segmentation accuracy in deep tissues, resulting in better recognition of neurons in the mouse brain and accurate assessment of nuclei in prostate lesions or mouse brain sections. Dark sectioning is compatible with many other microscopy modalities, including light-sheet and light-field microscopy, as well as processing algorithms, including deconvolution and super-resolution optical fluctuation imaging.
研究领域:
显微镜技术
·
生物成像
·
计算成像
·
细胞生物学
·
神经科学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MATERIALS LETTERS
·
2012
·
IF 2.307
Shilu Wang,Guoming Zhao
Nanofibers were electrospun from gelatin and chitosan at different mass ratios (gelatin/chitosan: 0/100, 25/75, 50/50, 75/25, 100/0). Atomic force microscopy (AFM) combined with scanning electron microscopy (SEM) was utilized in this study to evaluate the morphological and mechanical properties of the gelatin–chitosan nanofibers. The SEM images showed that the electrospun gelatin–chitosan nanofibers possessed more uniform morphologies than the pure gelatin or chitosan nanofibers. Moreover, AFM-HarmoniX mode was used to quantitatively assess the Derjaguin–Müller–Toporov (DMT) modulus of gelatin–chitosan nanofibers. After modified by two correction factors, the DMT modulus of gelatin–chitosan nanofibers showed higher values than the pure gelatin or chitosan nanofibers, which indicated the existence of intermolecular interaction within the electrospun gelatin–chitosan nanofibers.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
DOI
高影响因子
ADVANCED MATERIALS
·
2025
·
IF 26.8
Chenyang Shi,Yuna Bae,Mingyi Zhang,James J. De Yoreo
Silk is a unique and exceptionally strong biological material. However, no synthetic method has yet come close to replicating the properties of natural silk. This shortfall is attributed to an insufficient understanding of both silk nanofibril structure and the mechanism of formation. Here in situ atomic force microscopy (AFM) and photo-induced force microscopy (PiFM) is utilized to investigate the formation process and define the basic structural paradigm of individual silk nanofibrils. By visualizing the multistage process of silk nanofibril formation, the importance of conformational transformations along the assembly pathway is revealed. Unfolded silk structures initially accumulate into amorphous clusters, which then evolve into crystal nuclei via conformational transformation into β-crystallites. Nanofibril elongation then occurs through the attachment of silk molecules at a single end of the nanofibril tip; this is facilitated through the formation of a new amorphous cluster that then repeats the aforementioned conformational transformation. However, enzymatic digestion of the amorphous regions leads to direct, rapid elongation of β-crystalline fibers. These findings imply that the energy landscape is characterized by shallow minima associated with intermediate states, which can be eliminated by introducing β-crystallites, and motivate research into the directed modification of the silk assembly pathway to select for features beneficial to specific applications.
研究领域:
生物材料学
·
结构生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Nano
·
2023
·
IF 17.1
Song Zhang,Zhe Li,Yu Bao,Song Lu,Zheng Gong,Hu-jun Qian,Zhong-yuan Lu,Shuxun Cui
As the initially discovered allotrope of boron, amorphous elementary boron (AE-B) has been reported for more than two centuries. Several possible structures of AE-B have been proposed during the past decades. Due to its noncrystalline nature, however, the structure of AE-B has not yet been determined. We notice that AE-B can be dissolved in organic solvents, although the solubility is very low. After surface adsorption from solution, the individual or the self-assembled structure of AE-B molecules can be characterized at the single-molecule or nanoscopic level, which may be helpful to reveal the molecular structure of AE-B. Atomic force microscopy (AFM) imaging shows that AE-B is a chain-like molecule with a thickness (or height) of 0.17 ± 0.01 nm, which agrees well with the diameter of a B atom, demonstrating that the structure of an AE-B molecule contains only one layer of B atoms. Results from high-resolution transmission electron microscopy (HRTEM) indicate that AE-B molecules can be self-assembled into a nanosheet with parallel lines. The width of each line is 0.27 nm, and the periodical length along the chain axial direction is 0.32 ± 0.01 nm. These results indicate that AE-B is composed of a ladder-like inorganic polymer with B4 as the structural unit. This conclusion is supported by the single-chain elasticity obtained by single-molecule AFM and quantum mechanical calculations. We expect that this fundamental study is not only an ending of the two-century-old scientific mystery but also the beginning of the research and applications of AE-B (ladder B) as a polymeric material. The research strategy may be also used to study other amorphous inorganic materials.
研究领域:
材料科学
·
纳米技术
✓ 已验证
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2021
·
IF 6.707
Fanfan Zhang,Haichang Yang,Xiahui Gui,Han Guo,Yijun Cao,Yaowen Xing
To develop interfacial nanobubbles (INBs) into application fields, it is of great significance to understand the properties of INBs and their effect on the interaction of inter-particles. In this paper, the morphology of INBs on different hydrophobic surfaces was researched by total internal reflection fluorescence microscopy (TIRF) and atomic force microscope (AFM). A hydrophobic AFM colloid cantilever was used to measure the interaction of inter-particles in the absence and presence of INBs. The results confirm that the formation of INBs is closely related to the hydrophobicity of substrates, more large INBs form on the strong hydrophobic surface (SS). Furthermore, the magnitude and range of the hydrophobic interaction force are positive related to the dimension of INBs. Besides, multiple approaches of hydrophobic colloid to SS, the hydrophobic interaction is further enhanced due to the merging and cavitation of INBs. Therefore, the results presented here provide the relationship between INBs formation and surface hydrophobicity , as well as the effect of INBs on particles interaction. The formation of INBs should be responsible for the hydrophobic interaction of inter-particles, which is a basic insight into the hydrophobic interaction between particles.
研究领域:
物理化学
·
表面科学
·
胶体科学
✓ 已验证
DOI
高影响因子
FOOD RESEARCH INTERNATIONAL
·
2021
·
IF 6.475
Zheng Wan,Huiping Xia,Shiyin Guo,Chaoxi Zeng
In this study, stable water-in-oil emulsions stabilized solely by a naturally occurring steroidal sapogenin was reported for the first time. The results show that a concentrated emulsion with an internal water ratio of up to 60% can be obtained with only 3% of diosgenin concentration. The concentration of diosgenin had a significant effect on the microstructure and rheological properties of the emulsions. More importantly, the emulsion has excellent freeze/thaw stability and thermal stability. The results of polarized light microscopy, CLSM, and XRD indicate that the great structural properties and high stability of the emulsion can be attributed to the combined action of the diosgenin crystal shells on the droplet surface and needle-crystals in the continuous phase. That is, Pickering stabilization and network stabilization acting synergistically on stabilization of the emulsions. This novel food grade water-in-oil emulsions demonstrated great potential for application in food and biomedical-related fields.
研究领域:
食品科学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2025
·
IF 9.8
Yong Xie,Qingqing Liu,Jia Shi,Renwei Zhu,Xiong Liu
Thermal processing of barley grains is a useful technique for modelling the physicochemical properties of β-glucans and their food applications. This study investigated the impacts of different thermal processing techniques—including flaking-roasting (FR), stir-frying (SF), steam flash-explosion (SFE), and popping expansion (PE)—on the gelation properties of hulless barley β-glucan. Results showed that PE-β-glucan showed the highest molecular weight ( M w 5243.6 ± 0.3 kDa), water holding capacity, solubility, zeta potential, gel stability, and texture properties, followed by native, SF-, and FR-β-glucan. However, SFE-β-glucan (lowest M w , 89.9 ± 0.2 kDa) failed to gel even at 60 mg/mL. Microstructure observations by atomic force microscope (AFM), confocal laser scanning microscope (CLSM), and transmission electron microscopy (TEM) indicated that PE-induced chain conformation changes primarily augmented cluster stability of β-glucan, strengthening gelation. Hence, β-glucan gel performance is jointly governed by molecular weight and chain conformation, both significantly altered by thermal processing.
研究领域:
食品科学
·
高分子科学
·
材料科学
·
农产品加工
·
生物物理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PHOTOCHEMICAL & PHOTOBIOLOGICAL SCIENCES
·
2020
·Vol. 19
·期 4
·485-494
·
IF 2.831
Ma Wenpeng,Liu Chengcheng,Li Jiao,Hao Ming,Ji Yanhong,Zeng Xiaoyan
The extensive and repetitive use of antifungal drugs has led to the development of drug-resistant Candida albicans . Antimicrobial photodynamic therapy (aPDT) has received considerable attention as an emerging and promising approach to combat drug-resistant microbes. This study evaluated the photodynamic effects mediated by aloe emodin (AE), a natural compound isolated from Aloe vera and Rheum palmatum, on azole-sensitive and azole-resistant C. albicans in vitro . AE exhibited no significant dark toxicity, but in the presence of light, effectively inactivated C. albicans cells in a concentration-dependent manner. The uptake of AE by fungal cells was investigated by confocal laser scanning microscopy (CLSM), and the results showed that AE possessed stronger ability to enter into C. albicans cells following light irradiation. Transmission electron microscopy analysis suggested that AE-mediated aPDT could induce damage to the cell wall, cytoplasm, and nucleus. Damage to the surface of C. albicans was observed by scanning electron microscopy. These results suggest that AE is a potential PS for use in aPDT of drug-resistant C. albicans strains, and AE-mediated aPDT shows promise as an antifungal treatment.
研究领域:
微生物学
·
药理学
·
抗菌治疗
·
真菌病理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Photodiagnosis and Photodynamic Therapy
·
2019
·
IF 2.589
Asif Jan,Chengcheng Liu,Hong Deng,Jiao Li,Wenpeng Ma,Xiaoyan Zeng,Yanhong Ji
Background and aim The extensive use of antifungal drugs has led to resistance from Candida albicans . The search for alternative treatment against drug-resistant C. albicans is highly desirable. Antimicrobial photodynamic therapy (aPDT) is an emerging and promising approach for treating localized and superficial C. albicans infections. The aim of this study was to investigate the photodynamic inactivation (PDI) effects of hypocrellin B (HB) on azole-sensitive and resistant C. albicans in vitro . Methods The PDI efficacies of HB on standard C. albicans strain (ATCC 10231), azole-sensitive clinical isolate of C. albicans , and azole-resistant clinical isolate of C. albicans were assessed. The uptake of HB in C. albicans cells was investigated by confocal laser scanning microscopy (CLSM). The PDI effects on cellular structure and surface characteristics were investigated by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Results HB exhibited no significant dark toxicity, but inactivated the azole-sensitive and resistant C. albicans in a light-dose and PS concentration-dependent manner. CLSM images indicated that PDI treated C. albicans cells showed stronger fluorescence compared to untreated cells. TEM images suggested that significant damage to the cell wall, membrane, and cytoplasm were induced by HB-mediated PDI. SEM analysis revealed that the surface of C. albicans cells became twisted and ruptured after PDI treatment. Conclusions Azole-sensitive and resistant C. albicans could be effectively inactivated by HB in the presence of light, and HB-mediated aPDT shows promise as an antifungal treatment for C. albicans .
研究领域:
微生物学
·
药理学
·
医学研究
✓ 已验证
产品关联
DOI
PubMed
高影响因子
NANOTECHNOLOGY
·
2021
·Vol. 32
·期 36
·365601
·
IF 3.874
Yankun Tang,Ming Zhang,Sher Ali Nawaz,Xianqing Tian,Hairong Wang,Jiuhong Wang
To achieve an ultra-low concentration formaldehyde detection at low temperature, a platinum (Pt) assisted TiO2 hierarchical nano blooming-flower sphere material is synthesized through hydrothermal method. SEM and transmission electron microscope characterizations show that the diameter of the nano sphere was around 2 μm with dissilient rods of 60 nm in diameter and 1 μm in length on the surface. The response (Ra/Rg) achieved form this nanomaterial to HCHO is 1.08 (100 ppb) and 5.82 (5 ppm) at 130 °C without an involvement of any light source or solution. The relationship curve between the responses and concentrations shows regular exponential trend. The verification of sensor stability done by a 3 month reliability test shows no response-degradation. The optimal response and stability is attributed to the massive dissilient rods on the surface of TiO2 spheres and the assistance of Pt as a catalyzer disperses to intensify the formation of depletion area on the surface of TiO2. This study provide an attractive and cost effective solution for the detection of HCHO in air at a relatively low temperature.
研究领域:
材料科学
·
环境科学
·
纳米技术
·
传感器技术
✓ 已验证
DOI
高影响因子
STAR Protocols
·
2023
·
IF 0
Xiao Chen,Xu-Man Chen,Quan Li
Summary Here, we present a protocol for the construction of a hierarchical host-guest supramolecular self-assembly system in water. We describe steps for determining the binding levels and capturing the morphologies of hierarchical self-assembly. We detail procedures for using UV-vis spectra, nuclear magnetic resonance spectra, scanning electron microscopy, and transmission electron microscopy for the assembly. This protocol is useful for analyzing the detailed chemical structure and morphological variation of hierarchical host-guest supramolecular self-assembly systems. For complete details on the use and execution of this protocol, please refer to Chen et al. (2022). 1
研究领域:
化学
·
材料科学
·
纳米技术
✓ 已验证
DOI
PubMed
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