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Label-free optical biosensors have become powerful tools in the study of biomolecular interactions without the need for labels. High throughput and low detection limit are desirable for rapid and accurate biomolecule detection. The oblique-incidence reflectivity difference (OI-RD) technique is capable of detecting thousands of biomolecular interactions in a high-throughput mode, specifically for biomolecules larger than 1000 Da. In order to enhance the detection capability of OI-RD for small molecules (typically

Optical biosensors have a significant impact on various aspects of our lives. In many applications of optical biosensors, fluidic chambers play a crucial role in facilitating controlled fluid delivery. It is essential to achieve complete liquid replacement in order to obtain accurate and reliable results. However, the configurations of fluidic chambers vary across different optical biosensors, resulting in diverse fluidic volumes and flow rates, and there are no standardized guidelines for liquid replacement. In this paper, we utilize COMSOL Multiphysics, a finite element analysis software, to investigate the optimal fluid volume required for two types of fluidic chambers in the context of the oblique-incidence reflectivity difference (OI-RD) biosensor. We found that the depth of the fluidic chamber is the most crucial factor influencing the required liquid volume, with the volume being a quadratic function of the depth. Additionally, the required fluid volume is also influenced by the positions on the substrate surface bearing samples, while the flow rate has no impact on the fluid volume.

The oblique-incidence reflectivity difference (OI-RD) microscope is a label-free detection system for microarrays that has many successful applications in high throughput drug screening. The increase and optimization of the detection speed of the OI-RD microscope will enable it to be a potential ultra-high throughput screening tool. This work presents a series of optimization methods that can significantly reduce the time to scan an OI-RD image. The wait time for the lock-in amplifier was decreased by the proper selection of the time constant and development of a new electronic amplifier. In addition, the time for the software to acquire data and for translation stage movement was also minimized. As a result, the detection speed of the OI-RD microscope is 10 times faster than before, making the OI-RD microscope suitable for ultra-high throughput screening applications.

Post‐collisional volcanic rocks of Mesozoic age occur in the regions adjacent to Gerze, part of the southern Qiangtang Terrane of northern Tibet, China. Geochronological, geochemical, and whole‐rock Sr‐Nd isotopic analyses were performed on the volcanic rocks to better characterize their emplacement age and models for their origin. Laser ablation‐inductively coupled plasma‐mass spectrometry (LA‐ICP‐MS) U‐Pb zircon analyses yielded consistent ages ranging from 123.1±0.94 Ma to 124.5±0.89 Ma for six volcanic rocks from the study area. The intermediate volcanic rocks belong to the alkaline and sub‐alkaline magma series in terms of K2O+Na2O contents (5.9%–9.0%), and to the shoshonitic and calc‐alkaline series on the basis of their high K2O contents (1.4%–3.3%). The Gerze volcanic rocks are characterized by the enrichment of light rare earth elements [(La/Yb)N=34.9–49.5] and large–ion lithophile elements (e.g., Rb, Ba, Th, U, K, Pb, and Sr), slightly negative Eu anomalies (Eu/Eu*=0.19–0.24), and negative anomalies in high field strength elements (e.g., Nb, Ta, Hf and Ti), relative to primitive mantle. The samples show slightly elevated (87Sr/86Sr)i values that range from 0.7049 to 0.7057, and low ∊Nd(t) values from –0.89 to –2.89. These results suggest that the volcanic rocks studied derived from a compositionally heterogeneous mantle source and that their parent magmas were basaltic. The more mafic, parental magmas to the Gerze volcanic rocks likely underwent fractional crystallization of clinopyroxene, hornblende, biotite, and potassium feldspar, during ascent, with little to no crustal contamination, prior to their eruption/emplacement. While these volcanic rocks exhibit geochemical signatures typical of magmas formed in a destructive plate‐margin setting, it is plausible that their mantle source might also have acquired such characteristics in an earlier episode of subduction. [ABSTRACT FROM AUTHOR]

Aims: To examine the association of weight status with the prevalence of blood pressure (BP), vital capacity, dental de-cay, and visual acuity among school-age children in Chengdu, China and to find the potential role of weight status to predict the common and frequently occurring diseases among school-age children. Methods: A cross-sectional study was conducted among 12,297 children aged 6-18 years from 10 schools in the Jinniu District of Chengdu, China. Body height, weight, waist circumference (WC), and BP were measured. Vital capacity, dental decay, and visual acuity were detected. Results: The overall prevalence of underweight, overweight, obesity, abdominal obesity, high BP, bad vital capacity weight index, dental decay, and low vision were 7.18, 13.47, 7.57, 18.90, 2.78, 21.93, 38.81, and 45.79%, respectively. After controlling for age, gender, and WC, it was found that overweight and obese children had a higher risk of developing high BP than normal weight children ([OR 4.20, p < 0.001] and [OR 8.76, p < 0.001], respectively), And adjusting forage, gender, and chest circumference, the risk of having bad vital capacity weight index among children with overweight and obesity was higher ([OR 2.15, p < 0.001] and [OR 5.40, p < 0.001], respectively), and the risk with underweight was lower (OR0.35, p < 0.001 ). After eliminating the influential factors of gender and age, children who were underweight were 1.16 times (OR 1.16, p = 0.048) more likely to have caries than children with normal weight, but obese children were found to have a lower prevalence for dental cavities than children with normal weight (OR 0.79, p = 0.002). Underweight and obese children had a higher prevalence of low vision; the OR of the appearance of low vision was 1.21 (p = 0.016) for underweight children and 1.23 (p = 0.009) for obese children after adjusting the age and gender. Conclusions: Abnormal weight status among Chengdu urban school-age children was found to be a severe health problem, and it was strongly associated with BP, vital capacity, dental decay, and visual acuity. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to identify novel proteins involved in retinoic acid (RA)-induced embryonic cleft palate development., Method: The palate tissues of the control and RA-treated E14.5 were dissected and subjected to iTRAQ-based proteomic analysis., Results: Differential expression analysis identified 196 significantly upregulated and 149 downregulated considerably proteins in RA-induced palate tissues. Comprehensive Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis revealed the significant involvement of cytoplasmic translation, ribosome biogenesis, glycolysis/gluconeogenesis, and glutathione metabolism pathways in cleft palate pathogenesis triggered by RA. In particular, ribosome-related pathways were highly enriched, while glycolysis was disrupted. Protein-protein interaction analysis, facilitated by the STRING database, revealed a tightly interconnected network of differentially expressed proteins. Further analysis using the cytoHubba plugin in Cytoscape identified ten hub proteins, including Eif4a1, Gapdh, Eno1, Imp3, Rps20, Rps27a, Eef2, Hsp90ab1, Rpl19, and Rps16, indicating their potential roles in RA-induced cleft palate development, and thus positioning them as potential biomarkers for cleft palate., Conclusion: These findings provide valuable insights into the proteomic changes associated with RA-induced cleft palate and shed light on key pathways and proteins that can contribute significantly to the pathogenesis of this congenital condition., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

On⁻off⁻on fluorescent sensors based on emerging carbon nanoparticles (CNPs) or carbon dots (CDs) have attracted extensive attention for their convenience and efficiency. In this study, dumped silkworm excrement was used as a novel precursor to prepare fluorescent nitrogen-doped CNPs (N-CNPs) through hydrothermal treatment. The obtained N-CNPs showed good photoluminescent properties and excellent water dispersibility. Thus, they were applied as fluorescence &ldquo;on⁻off⁻on&rdquo; probes for the detection of Fe(III) and biothiols. The &ldquo;on⁻off&rdquo; process was achieved by adding Fe(III) into N-CNP solution, which resulted in the selective fluorescence quenching, with the detection limit of 0.20 &mu;M in the linear range of 1⁻500 &mu;M. Following this, the introduction of biothiols could recover the fluorescence efficiently, in order to realize the &ldquo;off⁻on&rdquo; process. By using glutathione (GSH) as the representative, the linear range was in the range of 1⁻1000 &mu;M, and the limit of detection was 0.13 &mu;M. Moreover, this useful strategy was successfully applied for the determination of amounts of GSH in fetal calf serum samples.