Optimal control-based inverse determination of electrode distribution for electroosmotic micromixer

This paper presents an optimal control-based inverse method used to determine the distribution of the electrodes for the electroosmotic micromixers with external driven flow from the inlet. Based on the optimal control method, one Dirichlet boundary control problem is constructed to inversely find the optimal distribution of the electrodes on the sidewalls of electroosmotic micromixers and achieve the acceptable mixing performance. After solving the boundary control problem, the step-shaped distribution of the external electric potential imposed on the sidewalls can be obtained and the distribution of electrodes can be inversely determined according to the obtained external electric potential. Numerical results are also provided to demonstrate the effectivity of the proposed method

Trifluorobenzamidine prevents allergic rhinitis by regulating IgE, IL-4 and IL-5 in T-cells

Purpose: To investigate the effect of trifluorobenzamidine (TBI) on a mouse model of ovalbumin (OVA)- induced allergic rhinitis. Methods: Allergic rhinitis was established in mice via sensitization on days 1, 5 and 14 through intraperitoneal injection of OVA (100 μg) in PBS. On day 15, the mice were subjected to intranasal exposure to OVA (1.5 mg dissolved in PBS). Prior to 10 days of intranasal exposure to OVA, the micewere treated with TBI at doses of 5, 10 and 20 μg/kg. Cytokine levels were determined using enzymelinked immunosorbent assay (ELISA) kits, while cyclooxygenase (COX)-2 and caspase-1 activity were assayed with western blotting. Results: Treatment with TBI significantly (p < 0.05) reduced OVA-mediated increases in nasal rub scores, and decreased serum levels of IgE, TNF-α, thymic stromal lymphopoietin (TSLP), IL-1β and histamine in mice. It also significantly regulated spleen weight and IL-4 secretion (p < 0.05) in OVAadministered mice. TBI significantly downregulated the expressions of IL-5, IL-13, TNFα, TSLP, IL-1β and IL-6 (p < 0.05). Administration of TBI caused a marked reduction in OVA-mediated increase in caspase-1 activity in mice intranasal tissues, and also significantly reduced OVA-induced excessive production of MIP-2 and ICAM-1 (p < 0.05). Moreover, TBI prevented OVA-induced infiltration of eosinophils and mast cells into intranasal tissues (p < 0.05). Conclusion: TBI reduces levels of IgE and various pro-inflammatory cytokines in OVA-administered mice. It also regulates Th1:Th2 ratio, inhibited activity of caspase-1, suppressed mast cell/eosinophil infiltration and reduced ICAM-1 and MIP-2 levels. Therefore, TBI possesses inhibitory potential against rhinitis allergy, and thus can potentially be developed as a new treatment strategy for asthma. Keywords: Trifluorobenzamidine, Anti-inflammation, Allergic rhinitis, Cytokines, Caspase-1, Itchin

Ultrasonic Assisted Machining of Nickel-Based Superalloy Inconel 718

Inconel 718 has been widely used in industries because of its excellent mechanical properties. However, the machining process, particularly the turning/grinding, of Inconel 718 is still costly due to high cutting force and heavy tool damage. Fortunately, a promising material removal technique, that is, ultrasonic-assisted turning/grinding (called UAT/UAG for simplicity), could potentially play a great role in the high efficiency precision machining of Inconel 718 due to its excellent features such as smaller turning/grinding force, better surface quality, longer tool working life and lower heat generation. However, few attempts have been done on UAT/UAG of Inconel 718. Therefore, in this work, in order to confirm the feasibility of machining Inconel 718 by UAT/UAG, experimental apparatus/equipment has at first been constructed by installing an ultrasonic cutting-unit/spindle on a NC lathe/surface grinder for UAT/UAG operations, and then experimental investigations have been performed to elucidate the fundamental machining characteristics involving Inconel 718 workpiece including the effects of the ultrasonic vibration and the cutting/grinding speed on the work-surface finish, the machining force and temperature, the chip formation, the tool/wheel wears and so on. The obtained results show that grinding forces and surface roughness were decreased in UAT/UAG

The effect on the seasonal dynamics of soil N transformation resulting from biochar application in karst mountains

Nitrogen (N) is frequently a limiting element for primary productivity in karst ecosystems due to its low availability. N mineralization drives N availability and is important for improving N use efficiency in soils. While the use of biochar in agricultural and forest ecosystems has attracted great attention recently, little has been reported on the seasonal dynamics of soil N transformation in karst and its response to biochar application. Therefore, we conducted a pot experiment over 1 year using two types of biochar (rice husk biochar and wood biochar) as soil amendments. The results demonstrated that in the karst mountain region, the soil had the highest content of mineral N (19.41 mg/kg) during summer and the lowest content of mineral nitrogen (3.74 mg/kg) during winter. There was a significant positive correlation (p < 0.01) between soil mineral N content and temperature, and between soil temperature and urease activity. Thus, the higher temperatures during summer enhance soil urease activity, making it easier for soil N mineralization to occur, and increasing soil mineral N content. The soil mineral N content of the CK treatment was 2.61–209.42% higher than the other treatments, indicating that the biochar application reduced the soil mineral N content, which was supported by the negative net N mineralization. This may be due to biochar facilitating the adsorption and immobilization of nitrogen. The soil mineral N content of rice husk biochar was significantly higher than that of woody biochar by 109.55%, indicating that woody biochar would adsorb more N or more readily stimulate N immobilization than rice husk biochar. Furthermore, soil N immobilization (negative net N mineralization) after biochar application varied according to the season. The higher temperatures during summer promoted soil N immobilization more with biochar application. These results are crucial to understanding soil N transformation in karst mountains and guiding effective soil management

Exendin-4 attenuates ischemia-induced ventricular arrhythmias in rats

Background: Glucagon-like peptide-1 and its receptor agonist-exendin-4 (Ex-4) have been shown to provide beneficial effects for cardiovascular diseases. This study investigated the effects of Ex-4 on ischemia-induced ventricular arrhythmias in rats. Methods: Anesthetized male rats were once treated with Ex-4 (5 &#956;g/kg, i.v.) 1 h before ischemia in the absence and/or presence of 5-hydroxydecanoic acid (5-HD, 10 mg/kg, i.v., a specific inhibitor of mitochondrial ATP-sensitive potassium [KATP] channels) which were once injected 10 min before ischemia. And then subjected to ischemia for 30 min. Ventricular arrhythmias were assessed. Results: During the 30-min ischemia, Ex-4 significantly reduced the incidence of ventricular fibrillation (VF) (p < 0.05). The duration of ventricular tachycardia (VT) + VF, the number of VT + VF episodes and the severity of arrhythmias were all significantly reduced by Ex-4 compared to those in myocardial ischemia group (p < 0.05 for all). Administration of 5-HD abolished the protective effects of Ex-4 on VF incidence, the duration of VT + VF, the number of VT + VF episodes and the severity of arrhythmias (p < 0.05 for all). Conclusions: This study suggested that Ex-4 could attenuate ischemia-induced ventricular arrhythmias in rats in which mitochondrial KATP channels may be involved

Optimal Control-Based Inverse Determination of Electrode Distribution for Electroosmotic Micromixer

This paper presents an optimal control-based inverse method used to determine the distribution of the electrodes for the electroosmotic micromixers with external driven flow from the inlet. Based on the optimal control method, one Dirichlet boundary control problem is constructed to inversely find the optimal distribution of the electrodes on the sidewalls of electroosmotic micromixers and achieve the acceptable mixing performance. After solving the boundary control problem, results are also provided to demonstrate the effectiveness of the proposed method; the step-shaped distribution of the external electric potential imposed on the sidewalls is obtained, and the electrodes with an interlaced arrangement are inversely derived according to the obtained external electric potential

FDNet: Feature Decoupled Segmentation Network for Tooth CBCT Image

Precise Tooth Cone Beam Computed Tomography (CBCT) image segmentation is crucial for orthodontic treatment planning. In this paper, we propose FDNet, a Feature Decoupled Segmentation Network, to excel in the face of the variable dental conditions encountered in CBCT scans, such as complex artifacts and indistinct tooth boundaries. The Low-Frequency Wavelet Transform (LF-Wavelet) is employed to enrich the semantic content by emphasizing the global structural integrity of the teeth, while the SAM encoder is leveraged to refine the boundary delineation, thus improving the contrast between adjacent dental structures. By integrating these dual aspects, FDNet adeptly addresses the semantic gap, providing a detailed and accurate segmentation. The framework's effectiveness is validated through rigorous benchmarks, achieving the top Dice and IoU scores of 85.28% and 75.23%, respectively. This innovative decoupling of semantic and boundary features capitalizes on the unique strengths of each element to significantly elevate the quality of segmentation performance.Comment: This work has been submitted to the IEEE ISBI 2024 for possible publication. Copyright may be transferred without notice, after which this version may no longer be accessibl