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1.
Opt Express ; 32(11): 19146-19162, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38859056

RESUMO

Fringe projection profilometry plays an important role for quality control in production line. However, it is facing challenges in the measurement of objects with intricate structures and high dynamic range that involved in precision manufacturing and semiconductor packaging. In this paper, a multi-view fringe projection profilometry system, which deploys a vertical telecentric projector and four oblique tilt-shift cameras, is presented to address the "blind spots" caused by shadowing, occlusion and local specular reflection. A flexible and accurate system calibration method is proposed, in which the corrected pinhole imaging model is used to calibrate the telecentric projection, and the unified calibration is performed by bundle adjustment. Experimental results show that the 3D repeated measurement error and standard deviation are no more than 10 µm within a measurable volume of 70 × 40 × 20 mm3. Furthermore, a group of experiments prove that the developed system can achieve complete and accurate 3D measurement for high dynamic range surfaces with complex structures.

2.
Microsyst Nanoeng ; 10: 81, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38911343

RESUMO

Photodetectors (PDs) play a crucial role in imaging, sensing, communication systems, etc. Graphene (Gr), a leading two-dimensional material, has demonstrated significant potential for photodetection in recent years. However, its relatively weak interaction with light poses challenges for practical applications. The integration of silicon (Si) and perovskite quantum dots (PQDs) has opened new avenues for Gr in the realm of next-generation optoelectronics. This review provides a comprehensive investigation of Gr/Si Schottky junction PDs and Gr/PQD hybrid PDs as well as their heterostructures. The operating principles, design, fabrication, optimization strategies, and typical applications of these devices are studied and summarized. Through these discussions, we aim to illuminate the current challenges and offer insights into future directions in this rapidly evolving field.

3.
Neurobiol Dis ; 199: 106584, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38945496

RESUMO

The temporal component of episodic memory has been recognized as a sensitive behavioral marker in early stage of Alzheimer's disease (AD) patients. However, parallel studies in AD animals are currently lacking, and the underlying neural circuit mechanisms remain poorly understood. Using a novel AppNL-G-F knock-in (APP-KI) rat model, the developmental changes of temporal order memory (TOM) and the relationship with medial prefrontal cortex and perirhinal cortex (mPFC-PRH) circuit were determined through in vivo electrophysiology and microimaging technique. We observed a deficit in TOM performance during the object temporal order memory task (OTOMT) in APP-KI rats at 6 month old, which was not evident at 3 or 4 months of age. Alongside behavioral changes, we identified a gradually extensive and aggravated regional activation and functional alterations in the mPFC and PRH during the performance of OTOMT, which occurred prior to the onset of TOM deficits. Moreover, coherence analysis showed that the functional connectivity between the mPFC and PRH could predict the extent of future behavioral performance. Further analysis revealed that the aberrant mPFC-PRH interaction mainly attributed to the progressive deterioration of synaptic transmission, information flow and network coordination from mPFC to PRH, suggesting the mPFC dysfunction maybe the key area of origin underlying the early changes of TOM. These findings identify a pivotal role of the mPFC-PRH circuit in mediating the TOM deficits in the early stage of AD, which holds promising clinical translational value and offers potential early biological markers for predicting AD memory progression.

4.
J Affect Disord ; 352: 525-535, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38403135

RESUMO

BACKGROUND: Adolescence is a period characterized by a high vulnerability to emotional disorders, which are modulated by biological, psychological, and social factors. However, the underlying mechanisms remain poorly understood. METHODS: Combining physical or emotional social defeat stress (PS and ES) and pair or isolation rearing conditions, we investigated the effects of stress type and social support on emotional behavior and central immune molecules in adolescent mice, including anxiety, social fear, and social interaction strategies, as well as changes in microglia-specific molecules (ionized calcium-binding adaptor molecule 1 (Iba1) and a cluster of differentiation molecule 11b (CD11b)) in the medial prefrontal cortex (mPFC), hippocampus (HIP), amygdala (AMY), and nucleus accumbens (NAc). RESULTS: Mice exposed to both physical stress and isolated rearing condition exhibited the highest levels of anxiety, social fear, and microglial CD11b expression in the NAc. In terms of social support, pair-housing with siblings ameliorated social fear and NAc molecular changes in ES mice, but not in PS mice. The reason for the differential benefit from social support was attributed to the fact that ES mice exhibited more active and less passive social strategies in social environment compared to PS mice. Further, the levels of stress-induced social fear were positively associated with the expression of microglial CD11b in the NAc. CONCLUSION: These findings offer extensive evidence regarding the intricate effects of multiple social factors on social anxiety and immune alteration in the NAc of adolescent mice. Additionally, they suggest potential behavioral and immune intervention strategies for anxiety-related disorders in adolescents.


Assuntos
Microglia , Núcleo Accumbens , Camundongos , Masculino , Animais , Núcleo Accumbens/metabolismo , Microglia/metabolismo , Interação Social , Fatores Sociais , Ansiedade , Estresse Psicológico/psicologia , Camundongos Endogâmicos C57BL
5.
Adv Mater ; 36(21): e2312137, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38350009

RESUMO

Manipulation of directional magnon propagation, known as magnon spin current, is essential for developing magnonic devices featuring nonvolatile functionalities and ultralow power consumption. Magnon spin current can usually be modulated by magnetic field or current-induced spin torques. However, these approaches may lead to energy dissipation due to Joule heating. Electric-field switching of magnon spin current without charge current is highly preferred but challenging to realize. By integrating magnonic and piezoelectric materials, the manipulation of the magnon spin current generated by the spin Seebeck effect in the ferrimagnetic insulator Gd3Fe5O12 (GdIG) film on a piezoelectric substrate is demonstrated. Reversible electric-field switching of magnon polarization without applied charge current is observed. Through strain-mediated magnetoelectric coupling, the electric field induces the magnetic compensation transition between two magnetic states of the GdIG, resulting in its magnetization reversal and the simultaneous switching of magnon spin current. This work establishes a prototype material platform that paves the way for developing magnon logic devices characterized by all electric field reading and writing and reveals the underlying physics principles of their functions.

7.
Microsyst Nanoeng ; 9: 84, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37408537

RESUMO

Flexible photodetectors are fundamental components for developing wearable systems, which can be widely used for medical detection, environmental monitoring and flexible imaging. However, compared with 3D materials, low-dimensional materials have degraded performance, a key challenge for current flexible photodetectors. Here, a high-performance broadband photodetector has been proposed and fabricated. By combining the high mobility of graphene (Gr) with the strong light-matter interactions of single-walled carbon nanotubes (SWCNTs) and molybdenum disulfide (MoS2), the flexible photodetector exhibits a greatly improved photoresponse covering the visible to near-infrared range. Additionally, a thin layer of gadolinium iron garnet (Gd3Fe5O12, GdlG) film is introduced to improve the interface of the double van der Waals heterojunctions to reduce the dark current. The SWCNT/GdIG/Gr/GdIG/MoS2 flexible photodetector exhibits a high photoresponsivity of 47.375 A/W and a high detectivity of 1.952 × 1012 Jones at 450 nm, a high photoresponsivity of 109.311 A/W and a high detectivity of 4.504 × 1012 Jones at 1080 nm, and good mechanical stability at room temperature. This work demonstrates the good capacity of GdIG-assisted double van der Waals heterojunctions on flexible substrates and provides a new solution for constructing high-performance flexible photodetectors.

8.
Opt Express ; 31(2): 3092-3113, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785308

RESUMO

3D imaging and metrology of complex micro-structures is a critical task for precision manufacturing and inspection. In this paper, an accurate and flexible calibration method for 3D microscopic structured light system with telecentric imaging and Scheimpflug projector is proposed. Firstly, a fringe projection 3D microscopy (FP-3DM) system consisting of a telecentric camera and a Scheimpflug projector is developed, which can take full advantage of the depth of field (DOF) and increase the measurement depth range. Secondly, an accurate and flexible joint calibration method is proposed to calibrate the developed system, which utilizes the established pinhole imaging model and Scheimpflug distortion model to calibrate telecentric imaging, and fully considers the correction and error optimization of the Scheimpflug projection model. Meanwhile, the optimized local homography is calculated to obtain more accurate sub-pixel correspondence between the camera and the projector, and the perspective-n-point (PnP) method make the 3D coordinate estimation of the feature point more accurate. Finally, a prototype and a dedicated calibration program are developed to realize high-resolution and high-precision 3D imaging. The experimental results demonstrate that the re-projection error is less than 1µm, and the 3D repeated measurement error based on feature fitting is less than 4µm, within the calibrated volume of 10(H)mm × 50(W)mm × 40(D)mm.

9.
RSC Adv ; 13(2): 1223-1228, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36686922

RESUMO

The liquid phase exfoliation (LPE) of layered black phosphorus (BP) material is essential in the field of electronics. N-Methyl-2-pyrrolidone (NMP) is one of the most promising precursors for obtaining BP nanosheets/nanoparticles, but the longer sonication time leads to smaller production of phosphorene. Herein, for the first time, the large lateral size fabrication of phosphorene was attained through NMP solvent by optimizing the process parameters. The resultant dispersions were characterized by atomic force microscopy, X-ray powder diffraction, Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, and ultraviolet-visible spectroscopy. The characterization results revealed that the average lateral sizes of BP nanoparticles were found to be 67.8 ± 18.6 nm and the lateral size of fabricated BP nanosheets was found to be 5.37 µm. Moreover, this research provides a strategic approach for the mass production of phosphorene for photodetection applications.

10.
Opt Express ; 30(24): 44321-44338, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36523110

RESUMO

Various micro-structure surface texturing methods have been used to produce optical functional surface in the grinding, such as the textured grinding wheel, wheel path control and off-spindle-axis grinding. However, those grinding technologies are inherently challenged to employ in large-scale surface grinding due to the extremely high requirement for wheel cutting profile dressing. In this study, a novel phase shift modulation based on wheel oscillation motion was proposed to generate the micro-structure array in ultra-precision grinding. The phase shift effect involved in the surface micro-structure generation is investigated, in which the role of the second phase shift on superimposed mode and micro-waviness forms is discussed. A theoretical model based on the tool superimposed oscillation is established to study the micro-structure texture generation mechanism by considering the second phase shift. The influence of modulation frequency in the case of phase shift and out of phase shift on the surface texture generation both for the striation pattern and micro-structure is compared to clarify the transition between the continuous grooves and the discrete micro-structure array. The study indicates that the phase shift modulation represents a novel paradigm for fabricating micro-structure array with considerable capability and high efficiency in ultra-precision grinding.

11.
Food Chem ; 393: 133334, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35653989

RESUMO

Merchants used frozen chicken to pass it off as chilled chicken, resulting in Economically Motivated Adulteration incidents. Here in this work, firstly, we established OPLS-DA and OPLS-R models based on metabolomics to obtain differential metabolites in chilled and frozen chicken (with different storage times), the PLS-DA model based on above differential compounds could achieve accuracy of 91% (training) and 100% (testing) for the adulteration identification of uncooked chilled and frozen chicken. Secondly, cooking study was carried out to identify the discrepancy of the cooked chilled and frozen chicken. Higher nicotinamide, o-acetyl-l-carnitine, hypoxanthine, and IMP levels indicated better nutrition quality and more desirable flavor in chilled chicken nuggets, while higher bitter and sour peptides in frozen chicken nuggets indicated the loss of freshness.


Assuntos
Galinhas , Culinária , Animais , Biomarcadores , Culinária/métodos , Congelamento , Metabolômica
12.
Pathol Oncol Res ; 28: 1610288, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35769830

RESUMO

Background: Histone deacetylase (HDAC) plays a crucial role in regulating the expression and activity of a variety of genes associated with tumor progression and immunotherapeutic processes. The aim of this study was to characterize HDAC pathway copy number variation (CNV) in pan-cancer. Methods: A total of 10,678 tumor samples involving 33 types of tumors from The Cancer Genome Atlas (TCGA) were included in the study. Results: HDAC pathway CNV and CNV gain were identified as prognostic risk factors for pan-cancer species. The differences of tumor characteristics including tumor mutational burden, tumor neoantigen burden, high-microsatellite instability, and microsatellite stable between HDAC pathway CNV altered-type group and wild-type group varied among the various cancer species. In some cancer types, HDAC pathway CNV alteration was positively correlated with loss of heterozygosity, CNV burden, ploidy, and homologous recombination defect score markers, while it was significantly negatively correlated with immune score and stroma score. There were significant differences in immune characteristics such as major histocompatibility complex class I (MHC-I), MHC-II, chemokines, cytolytic-activity, and IFN-γ between the two groups. Immune cycle characteristics varied from one cancer type to another. Conclusion: This study reveals a tumor and immune profile of HDAC pathway CNV as well as its unlimited potential in immune prognosis.


Assuntos
Variações do Número de Cópias de DNA , Neoplasias , Variações do Número de Cópias de DNA/genética , Histona Desacetilases/genética , Humanos , Instabilidade de Microssatélites , Neoplasias/genética , Prognóstico
13.
Front Microbiol ; 13: 811784, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35602084

RESUMO

Natural antimicrobials (NAM) are promising candidates for the successful control of poultry-borne bacteria, carrying potent antimicrobial activity (AMA) against a wide range of multidrug-resistant pathogens. Individual activities of carvacrol, eugenol, trans-cinnamaldehyde, oregano, and thymol, along with the combined activity of paired compounds, were examined using broth microdilution and checkerboard techniques. The characteristic interactions between the compounds were calculated using an improved method, based on combination index (CI) values. The bacteria examined herein were selected due to their known genetic resistance to at least one antibiotic. Our results indicated that thymol was most effective, exhibiting the lowest minimum inhibitory concentration (MIC) value against Salmonella pullorum, Escherichia coli, and Klebsiella pneumoniae, establishing the order of antimicrobial efficacy as: thymol > oregano > carvacrol > trans-cinnamaldehyde > eugenol. In the interaction study, the paired combination of carvacrol and thymol showed synergistic effects and was highly effective in reducing the antibiotic resistance of all the evaluated pathogens. Notably, all CI values were <1.0 in evaluations of S. pullorum, indicating the absence of antagonism between eugenol and thymol (or oregano). In K. pneumoniae, majority of CI values, which had a few concentration points, were smaller than 1.0, indicating a synergistic effect between eugenol and carvacrol (oregano or thymol), and trans-cinnamaldehyde and carvacrol. In E. coli, apart from some concentration points, some CI values were smaller than 1.0, demonstrating a synergistic effect between eugenol and carvacrol, and thymol and carvacrol (eugenol or oregano). It is therefore of great significance to investigate and illuminate the minimal effect concentration of these five components when they are used in combination as feed additives. Moreover, the improved evaluation method of this study provides a precise and extensive means to assess the synergistic effects of NAM.

14.
Front Microbiol ; 13: 820833, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35432247

RESUMO

With widespread use of antibiotics in the aquaculture industry, bacterial resistance has recently attracted increasing attention. Continuous emergence of multi-resistant bacteria has greatly threatened human and animal health, as well as the quality and safety of livestock products. To control bacterial resistance, the effect of bacterial resistance needs to be well understood. The purpose of this study was to explore the factors influencing Escherichia coli (E. coli) drug resistance in large-scale pig farms. In this study, 296 strains of E. coli isolated and identified from large-scale pig farms in Beijing were used as the research objects. In vitro drug sensitivity tests were used to determine the sensitivity to 10 antibiotics of pig-derived E. coli. SPSS logistic regression was employed to analyze the effects of the season, pig type, sampling point (medication type) and sampling location on resistance and multi-drug resistance of E. coli from pigs. The degrees of drug resistance to 10 antibiotics of the 296 strains of pig-derived E. coli were varied, their resistance rates were between 4.05 and 97.64%, and their multi-drug resistance was appalling, with the highest resistance to six antibiotics being 26.35%. The isolated strains were proven more resistant to tetracyclines, penicillin and chloramphenicol, which are commonly used for disease prevention in pig farms, and less resistant to quinolones and aminoglycosides, which are not used in pig farms. The resistance of the isolated strains in spring and summer was generally higher than that in winter. E. coli resistance in piglets, fattening pigs and sows was more serious than that in nursery and sick pigs. The results showed that the season, type of medication and type of pig had an influence on the pig-derived E. coli resistance, among which the type of medication was the most influencing factor.

15.
Molecules ; 27(6)2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35335150

RESUMO

The solvent extraction, complexing ability, and basicity of tetradentate N-donor 2,9-bis(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-1,2,4-benzotriazin-3-yl)-1,10-phenanthroline (CyMe4-BT- Phen) and its derivatives functionalized by Br, hydroxyphenyl, nitryl were discussed and compared. It was demonstrated that four BTPhen ligands are able to selectively extract Am(lll) over Eu(lll). It was notable that the distribution ratio of 5-nitryl-CyMe4-BTPhen for Eu(lll) was suppressed under 0.02, which was much lower compared to DEu(lll) = 1 by CyMe4-BTPhen. The analysis of the effect of the substituent on the affinity to lanthanides was conducted by UV/vis and fluorescence spectroscopic titration. The stability constants of various ligands with Eu(lll) were obtained by fitting titration curve. Additionally, the basicity of various ligands was determined to be 3.1 ± 0.1, 2.3 ± 0.2, 0.9 ± 0.2, 0.5 ± 0.1 by NMR in the media of CD3OD with the addition of DClO4. The basicity of ligands follows the order of L1 > L2 > L3 > L4, indicating the tendency of protonation decreases with the electron-withdrawing ability increase.

16.
Foods ; 11(6)2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35327268

RESUMO

For the protection of Protected Geographical Indication (PGI) Sunite lamb, PGI Sunite lamb samples and lamb samples from two other banners in the Inner Mongolia autonomous region were distinguished by stable isotopes (δ13C, δ15N, δ2H, and δ18O) and two local modeling approaches. In terms of the main characteristics and predictive performance, local modeling was better than global modeling. The accuracies of five local models (LDA, RF, SVM, BPNN, and KNN) obtained by the Adaptive Kennard-Stone algorithm were 91.30%, 95.65%, 91.30%, 100%, and 91.30%, respectively. The accuracies of the five local models obtained by an approach of PCA-Full distance based on DD-SIMCA were 91.30%, 91.30%, 91.30%, 100%, and 95.65%, respectively. The accuracies of the five global models were 91.30%, 91.30%, 91.30%, 100%, and 91.30%, respectively. Stable isotope ratio analysis combined with local modeling can be used as an effective indicator for protecting PGI Sunite lamb.

17.
Opt Express ; 30(2): 2390-2401, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35209380

RESUMO

A chromatic confocal measurement method based on a phase Fresnel zone plate (FZP) is described. Strong dispersion of FZP results in significant axial focal shift. The axial dispersion curve is close to linear within a certain wavelength range determined by the quantitative calculation using the vectorial angular spectrum theory. A 11.27 mm diameter phase FZP with a primary focal length of 50 mm was processed using standard photolithography technology and used as the dispersive objective in a homemade chromatic confocal measurement system. The calibrated axial measurement range exceeds 16 mm, the axial resolution reaches 0.8 µm, and the measurement accuracy of displacement is better than 0.4%. This chromatic confocal sensor has been practically used in the measurement of step height, glass thickness, and 3D surface profile. The proposed method has the obvious characteristics of simplicity, greatly reduced cost and superior performance. It is believed that this sensing method has broad application prospects in glass, coating, machinery, electronics, optics and other industries.

18.
Opt Express ; 30(4): 5329-5346, 2022 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-35209499

RESUMO

Ultra-precision grinding is crucial for manufacturing high-end optics and molds, while the unbalanced wheel vibration is inevitable and becomes even more critical in surface generation, which resulted in undesired waviness and micro-texture on the ground surface. In this paper, to understand and control the micro-texture generation, a theoretical model has been developed to predict the deterministic surface micro-texture generation resulted from unbalanced tool vibration in ultra-precision grinding, in which the overlap trajectories of grinding wheel with an arc cutting edge were analyzed and calculated. The simulation work was performed and a double phase mechanism involved in deterministic textural pattern and structure has been revealed. Both theoretical and experimental results proved that phase shift is an important factor to determine micro-texture evolution in the ultra-precision grinding process. On this basis, a novel tool path strategy has been proposed to fabricate deterministic micro-structure by coordinating oscillation motion of the grinding wheel and phase shift control, in which a rhombus-shaped micro-structure array can be generated. A small adjustment for the phase shift was conducted and it was found that the more complex micro-texture with different textural patterns and micro-structure can be machined. The results indicated that the phase control for the tool path planning is an effective method to fabricate flexible and tunable micro-texture surfaces in ultra-precision grinding.

19.
Microsyst Nanoeng ; 8: 9, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35070351

RESUMO

Graphene/silicon Schottky junctions have been proven efficient for photodetection, but the existing high dark current seriously restricts applications such as weak signal detection. In this paper, a thin layer of gadolinium iron garnet (Gd3Fe5O12, GdIG) film is introduced to engineer the interface of a graphene/silicon Schottky photodetector. The novel structure shows a significant decrease in dark current by 54 times at a -2 V bias. It also exhibits high performance in a self-powered mode in terms of an Ilight/Idark ratio up to 8.2 × 106 and a specific detectivity of 1.35 × 1013 Jones at 633 nm, showing appealing potential for weak-light detection. Practical suitability characterizations reveal a broadband absorption covering ultraviolet to near-infrared light and a large linear response with a wide range of light intensities. The device holds an operation speed of 0.15 ms, a stable response for 500 continuous working cycles, and long-term environmental stability after several months. Theoretical analysis shows that the interlayer increases the barrier height and passivates the contact surface so that the dark current is suppressed. This work demonstrates the good capacity of GdIG thin films as interlayer materials and provides a new solution for high-performance photodetectors.

20.
Appl Opt ; 61(32): 9625-9633, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36606903

RESUMO

The measurement accuracy of telecentric imaging technique straightforwardly depends on the calibration of the telecentric camera. We present a flexible and simple calibration method based on a telecentric imaging model and orthogonality of rotation matrix. First, we use the orthogonality of rotation matrix to solve the magnification. Second, the external parameters are solved by the imaging model, and the ambiguity of sign is solved. Finally, we use the LM nonlinear optimization method to solve the distortion parameters. Experimental results show that the reprojection error is 0.7 pixels, which represents the actual dimension of 6.37 µm. In addition, the standard measuring block and real objects are measured, and the results verify the measurement accuracy and robustness of the proposed method.

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