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关键词： Gold nanoparticles   Turkevich method   functionalization   thioureas   absorption spectra  

摘要： Understanding the impact of functionalizing gold nanoparticles with thiourea derivatives is essential for optimizing their physicochemical properties and developing platforms based on the integration of these systems for specific applications. Gold nanoparticles functionalization with acylthioureas is a novel approach due to the lack of prior literature on this class of compounds. In this work, gold nanoparticles were obtained by the Turkevich method using a gold precursor/reducing agent ratio of 1/10.5. The nanoparticles were characterized using UV-Vis spectroscopy, electrophoretic light scattering, and transmission electron microscopy. The surface plasmon resonance band of the nanoparticles was used to evaluate the impact of their interaction with thiourea and 1-(2-furoyl)-3-phenylthiourea in aqueous media, and the electrochemical response of the thiourea derivative was previously evaluated on an Au(111) electrode. Finally, solid-phase diffuse reflectance spectra of the samples involved in this system were obtained as direct evidence of the functionalization of the gold nanoparticles. This multi-technique characterization provided robust evidence of successful surface modification and colloidal stability. Crucially, this study provides the first evidence of a key advantage: 1-(2-furoyl)-3-phenylthiourea effectively modifies the nanoparticle surface without inducing significant aggregation, a common limitation with simple thiourea. Additionally, an insightful discussion on tautomerism and substituent effects in explaining the differences in aggregation behavior between both compounds is addressed.

关键词： aqueous humor   carbonic anhydrase-1   cytokine   diabetic macular edema   diabetic retinopathy  

摘要： Purpose: This study aimed to investigate the expression of carbonic anhydrase-1 (CA-1) in the aqueous humor of patients with diabetic macular edema (DME) and to explore its correlations with other cytokines and macular structure in a real-world setting. Methods: This was a retrospective cross-sectional study. A total of 74 patients were enrolled in the DME group, and 30 patients were included in the control group. Aqueous samples were collected before intravitreal injections or relevant surgical procedures. The concentrations of CA-1, prekallikrein (PK), intercellular adhesion molecule-1 (ICAM-1), vascular intercellular adhesion molecule-1 (VCAM-1), monocyte chemoattractant protein-1 (MCP-1), vascular endothelial growth factor (VEGF), interleukin-6 (IL-6), and interleukin-8 (IL-8) were measured using a cytometric bead array (CBA). Retinal structural biomarkers were examined using optical coherence tomography (OCT) and fundus photography. Results: The levels of CA-1 in the aqueous humor were markedly elevated in patients with DME compared to the control group. The DME group showed a significantly higher geometric mean CA-1 level than the control group (geometric mean ratio = 10.65, 95% CI: 3.64-31.14, p < 0.001). Receiver-operating characteristic curve analyses (AUC = 0.89;95% CI: 0.871-0.981, p < 0.001) revealed that CA-1 has a strong discriminatory ability for distinguishing DME patients. In addition, other cytokines (PK, ICAM-1, VCAM-1, and IL-8) in the aqueous humor were elevated in the DME group compared to the control group (p < 0.05). In the DME group, CA-1 levels exhibited positive correlations with PK, ICAM-1, VCAM-1, MCP-1, VEGF, IL-6, and IL-8 (r = 0.306, 0.551, 0.347, 0.589, 0.349, 0.248, and 0.538, respectively;all p < 0.05). Conversely, CA-1 levels showed a negative correlation with retinal hemorrhage (r = -0.330, p = 0.016) and did not show significant association with other macular structural parameters. Conclusion: In DME patients, CA-1 levels were s

关键词： Feeds   Radio broadcasting   Frequency modulation   Circuits   Very large scale integration   Capacitors   Voltage multipliers   Integrated circuits   Circuits and systems   Latches   Computing-in-memory (CIM)   pipeline   resistive random access memory (ReRAM)   successive approximation (SAR)  

摘要： Computing-in-memory (CIM) based on resistive random access memory (ReRAM) has emerged as a promising solution for energy-efficient edge intelligence. However, existing analog-domain CIM systems still face significant challenges, including limited sensing margin, pronounced nonlinearity, and excessive hardware overhead in multibit computing scenarios. This article presents a 65-nm ReRAM-based nvCIM macro to address these limitations through several key innovations. A cascode-structured 3T2R memory cell is proposed to enhance read linearity and significantly improve the sensing margin (with 2.1 & times;and 29 & times;higher on/off current ratio than the WH-2T1R and 1T1R cell, respectively), while suppressing leakage-induced sensing margin degradation. It also mitigates the current deviation induced by IR-drop, ensuring accurate large-scale parallel MAC operations. A charge-sharing and clock-feedthrough compensation scheme is implemented to stabilize analog MAC outputs and expand the sensing window. For the readout stage, a 2-bit output comparator with a successive approximation (SAR)-like architecture is designed, requiring only a single external reference voltage. Additionally, a 4-bit two-stage pipelined comparator is further integrated to achieve 1-GS/s 4-bit quantization while reducing the time window without sacrificing accuracy. Simulation results demonstrate that the proposed macro successfully operates up to 1 GHz for 2/2/4b input/weight/output precision, achieving an energy efficiency of 142 TOPS/W with only 0.8% and 3.3% degradation in inference accuracy for the MNIST and CIFAR-10 datasets. These results validate the scalability, high throughput, and energy efficiency of the proposed design for next-generation ReRAM-based CIM architectures.

关键词： Genotyping   Expression   Growth   IGF1   Sheep  

摘要： Background Growth traits are critical determinants of productivity and profitability in sheep breeding programs. The Insulin-like growth factor-1 (IGF-1) gene plays a key role in regulating growth, metabolism, and carcass traits. The genetic analysis of IGF-1 genetic polymorphism, circulating hormone levels and age-specific gene expression at different growth stages in Muzaffarnagari sheep has not been previously reported. The present study was designed to analyze IGF-1 polymorphism, plasma IGF-1 concentration and gene expression pattern across different age groups in Muzaffarnagari sheep breed. Methods and results Genotyping of IGF-1 gene was carried out using high resolution melting (HRM) analysis and revealed three genotypes in the population. The percent distribution of AA, AB and BB genotypes were 91.6%, 6.3% and 2.1%, respectively. The plasma IGF-1 concentration was measured by ELISA at various age groups such as 3 months, 9 months, and adults (> 18 months). The least squares means of plasma IGF1 concentration was 7.76, 9.63 and 12.69 ng/mL at 3, 9 months of age and adults, respectively, which was significantly higher (p < 0.05) in adults. Gene expression analysis was carried out using peripheral blood mononuclear cells (PBMCs), which provides a reliable source for assessing the endocrine-related transcriptional activity. The m-RNA expression pattern of IGF-1 at 3, 9 months and adult age groups had 1.867, 3.052 and 1.701-fold as compared to the control. Conclusion The IGF plays a significant role in growth regulation during multiple development stages in sheep, however, it required to understand the role of IGF-1 at cellular level as well establish the association with production performance in-vivo. Overall, the present study provides novel insights into the genetic polymorphism, endocrine, and transcriptional regulation of IGF-1 gene in Muzaffarnagari sheep with implications for marker-assisted selection in growth-oriented breeding programs.