Competitive Flow Research Articles

Lateral flow immunoassay based on aggregation induced emission nanobeads for the sensitive and accurate detection of chloramphenicol in pig hair

Chloramphenicol (CAP) is a once widely used antibiotic, which is able to cause great harm to human health, is banned in some countries or organizations such as China, USA and the European Union for animal breeding. Because CAP in pig hair degraded slower and had amount of residues, pig hair could be used as the target to detect CAP residues. In this study, a competitive lateral flow immunoassay (LFIA), whose label was aggregation induced emission fluorescent nanobeads (AIEFN), was firstly developed for the detection of CAP in pig hair samples. It exhibited a low limit of detection (0.001 μg/kg) and a broad linear range (0.0025–0.32 μg/kg). The recovery rate and coefficient variation with spiked pig hair samples were 88.50%–106.17 % and 1.01%–7.37 %, which indicated good accuracy of this assay. The result of AIEFN-LFIA for the detection of CAP in pig hair was consistent with that of liquid chromatography-mass spectrometry. This assay was rapid with the total detection duration of about 20 min. AIEFN-LFIA was able to be used for rapid, sensitive, accurate and convenient detection of CAP residues in pig hair samples.

Preliminary Development of DNA Aptamer Quantum Dot-Based Competitive Lateral Flow Assays for Saxitoxin and Tetrodotoxin.

Initial proof-of-concept development of competitive lateral flow (LF) test strips involving red quantum dots (Qdots) is demonstrated with visible confirmation of the competitive displacement of Qdot-protein-saxitoxin (Stx) and -tetrodotoxin (Ttx) conjugates over 15min. The measured limits of detection (LODs) for the best versions of the assays were in the 1-2µg range when a bovine serum albumin (BSA)-Stx or -Ttx conjugate was used as the analyte for safety reasons and NIH ImageJ image analysis was applied. However, when one assumes that only one of the primary amines in BSA labeled with Stx or Ttx is needed as the "epitope" for capture and calculates the weight of the toxin adducts on an equal mole basis to that of 1µg of toxin-BSA conjugate, the LODs are as low as 4.5ng of toxin. No cross-reactivity was seen for these prototype test strips when BSA-Stx and BSA-Ttx were switched as analytes at or near their respective LODs which is in agreement with published specificity and affinity studies for these aptamers in the literature.

Chitosan-based multimodal polymeric nanoparticles targeting pancreatic β-cells

Multimodal in vivo imaging of pancreatic islets might improve monitoring of endocrine grafts upon implantation, helping clinical validation of new regenerative therapies based on the replacement of β-cells in type 1 diabetes affected patients. Herein, the generation of chitosan-based multimodal diagnostic nanoparticles (NPs) able to target β-cells is described. The NPs, composed of chitosan (CH) and γ-poly-glutamic-acid (γ-PGA) with different “clickable” functional groups were chemoselectively decorated at the surface with Exendin-4 (Ex4), a ligand of glucagon-like peptide 1 (GLP-1) β-cell receptors, and with a DOTA containing linker, to chelate diagnostic radioisotopes. Furthermore, the NPs were conjugated with IRDye®800CW for multispectral optoacoustic tomography (MSOT). The affinity of Ex4 decorated NPs towards GLP-1R was confirmed by competitive flow cytometry tests. The detectability of the NPs labeled with IRDye®800CW and Ex4 in MSOT experiments was demonstrated. In vivo biodistribution of Ex4 decorated NPs labelled with Ga-68 was studied with positron emission tomography (PET) experiments in mice. Specific binding to GLP-1 receptor expressing tissue was demonstrated in autoradiography experiments, showing potential of the multimodal NPs for specifically targeting β-cells.

TMIC-63. DUAL IMMUNE CHECKPOINT BLOCKADE IN A NOVEL EGFR-DRIVEN MURINE GLIOMA MODEL INCREASES PERIPHERAL T CELL PROLIFERATION BUT FAILS TO PROLONG SURVIVAL

Abstract Patients with glioblastoma (GBM) survive only 15-18 months following standard-of-care surgical resection and radio-chemotherapy. Immune checkpoint blockade (ICB), effective in extracranial cancers, failed to improve survival in patients with recurrent GBM in a multi-center phase III clinical trial. As such, we are interested in the molecular mechanisms that drive ICB resistance. Oncogenic EGFR activation is observed in ~50% of GBMs and is associated with immunosuppression; however, whether EGFR signaling impairs T cell function in GBM resulting in limited ICB efficacy remains unclear. Therefore, we leveraged the novel MADR-mEGFRvIII glioma model, which expresses murine EGFRvIII under a tetracycline-off system, to investigate the relationship between EGFR activation and responsiveness to dual anti-PD-1 and anti-CTLA-4 (10mg/kg) in vivo. Mice were bled prior to enrollment and weekly thereafter, which confirmed anti-PD-1-PD-1 binding via competitive flow cytometric assay. Following two weeks on treatment, animals were euthanized for immunophenotypic analyses of tumors and tumor-draining lymph nodes. These analyses revealed a significantly increased prevalence of peripheral CD11b+ myeloid cells and enhanced peripheral T cell proliferation, indicated by Ki67 positivity, after treatment with dual ICB compared to isotype control. However, these shifts did not translate to effective ICB-mediated recruitment of peripheral T cells to the tumor microenvironment and no significant survival benefit was observed (p=0.68, n=15/treatment arm). Given our previous findings that EGFR ablation via doxycycline enhanced intratumoral T cell infiltration, we hypothesize the rational combination of EGFR-targeted therapy and ICB will have a synergistic effect; thus, future directions include a study combining the two treatment regimens consisting of a lead-in with doxycycline to increase intratumoral T cell trafficking, followed by treatment with dual ICB. This work will provide insight into the interplay between oncogenic signaling and immunosuppression, contributing to the development of novel combination therapies in treating this lethal disease.

The utility of angiography-derived fractional flow reserve in predicting graft occlusions prior to bypass surgery

Abstract Background Occurrence of graft occlusion following coronary artery bypass graft (CABG) surgery has been linked to the presence of native coronary artery competitive flow (1). Despite its routine use in guiding revascularization, coronary angiography lacks sensitivity for assessing coronary stenosis significance. Data regarding the use of pressure-derived fractional flow reserve (FFR) to assess the hemodynamic significance of coronary stenoses prior to CABG are inconclusive (2) and the penetration of FFR in clinical routine is limited for various reasons (3). Different systems have been developed to predict FFR based on coronary angiographic images, eliminating pressure wires or hyperemic agents (4). Preliminary data demonstrated a high concordance between off-site angiography-derived FFR and pressure wire–based FFR (5-7). However, the use of this technique prior to CABG is not well studied. Purpose This study aims to correlate pre-CABG angiography-derived FFR with graft occlusion. Secondary endpoint is the correlation between the presence of at least one occluded bypass graft and overall mortality. Methods Retrospective study of patients undergoing CABG in whom a follow-up angiogram has been performed. Angiography-based FFR was calculated with a dedicated software (vFFR, CAAS 8.2 Workstation, Pie Medical Imaging), obtaining each major native coronary vessel before CABG. Post-CABG angiograms were conducted at least 6 weeks post-surgery to exclude graft-failures due to technical factors and thrombosis. Results From 2005 and 2014, 204 patients underwent pre-CABG angiography, with post-CABG angiograms at a median of 3.85 years [IQR 1.33-8.80] post-surgery. In total, 125 patients had to be excluded due to inadequate angiogram quality for vFFR assessment (outdated imaging system, improper vessel angles, vessel overlap, insufficient contrast). Consequently, 79 patients were suitable for pre-CABG vFFR analysis, including 132 grafted vessels (93 arterial and 39 saphenous grafts). The median patient age was 68 years [IQR 58-72] and mean time for clinical follow-up was 9.9±3.6 years. Vessels analyzed using vFFR were left anterior descending (LAD) (n=60, 45.5%), left circumflex (LCX) (n=39, 29.5%), ramus intermedius (RIM) (n=8, 6.1%) and right coronary artery (RCA) (n=25, 18.9%). Mean pre-CABG vFFR was 0.59±0.15. To predict graft occlusion, a vFFR cut-off value of 0.745 with an area under the curve (AUC) of 0.847 (95%CI 0.752–0.942) had a specificity of 0.722 and a sensitivity of 0.902 (Figure A). There was no difference in overall-mortality when comparing patients with at least one occluded bypass graft to those without (57.1% vs. 57.9%, p=0.949, Figure B). Conclusions vFFR can be used as a noninvasive tool to predict graft patency in patients undergoing CABG with acceptable sensitivity and specificity. Bypass graft occlusion did not correlate with overall-survival in this cohort.

Construction of a Multi-Level Strategic System for Cultivating Cultural Industry Management Talents in Colleges and Universities

Through SWOT (strengths, weaknesses, opportunities, and threats) and PEST (political, economic, social, and technological) analysis, this study discusses the construction of a multi-level strategic system for the cultivation of cultural industry management talents in colleges and universities. First of all, based on SWOT analysis, it is found that colleges and universities have rich educational resources and policy support, but they face challenges such as insufficient practical teaching and intensified international competition. External opportunities come from the rapid development of the cultivation of cultural industry management talents and policy promotion, while threats come from global market competition and talent flow. Secondly, PEST analysis reveals the key factors in the macro-environment: at the political level, the state vigorously supports the cultivation of cultural industry management talents; at the economic level, the market demand for cultural industries is strong; at the social level, the public cultural consumption is upgraded; at the technological level, digital transformation promotes industry innovation. On this basis, this paper puts forward a multi-level strategic system covering theoretical education, practical skill improvement, interdisciplinary integration, and international vision training. The system aims to solve the problems existing in talent training in colleges and universities and cultivate high-quality cultural industry management talents with theoretical knowledge, practical skills, and global vision, so as to adapt to the increasingly complex and diversified cultural industry management talents market demand and promote the long-term development of the industry.

Modular Point-of-Need Tropane Alkaloid Detection at Regulatory Levels: Combining Solid-Liquid Extraction from Buckwheat with a Paper-Immobilized Liquid-Phase Microextraction and Immuno-Detection in Interconnectable 3D-Printed Devices.

Contamination with tropane alkaloids in cereals is expected to increase globally. However, current identification tools (e.g., liquid chromatography-mass spectrometry) for tropane alkaloids are time-consuming and expensive. Furthermore, their miniaturized alternatives lack sensitivity and robustness. Therefore, there is a pressing need for inexpensive and effective screening methods. Here, an on-site applicable modular workflow for tropane alkaloid detection in buckwheat is presented. The modular workflow combines paper microfluidics and interconnectable 3D-printed sample preparation tools and was evaluated for different tropane alkaloids, including atropine and scopolamine. Furthermore, integration with an indirect competitive lateral flow immunoassay (icLFIA) for atropine detection at relevant levels was demonstrated. In the modular workflow, to minimize matrix coextraction, tropane alkaloids were extracted from the milled buckwheat cereals by a mixture of alkaline aqueous and immiscible organic solvents (extraction recoveries: 66-79%). The tropane alkaloids were subsequently concentrated with a newly developed paper-immobilized liquid-phase microextraction (PI-LPME, extraction recoveries: 34-60%, concentration factor to immobilized solution in paper: 60-108×). After the PI-LPME, with an integrated 3D-printed setup, the tropane alkaloids were directly eluted (elution recoveries: 83-93%) and detected with the icLFIA. Digital read-out of the icLFIA, by employing a hand-held reader, enabled semiquantification of atropine (IC50 = 0.56 ng mL-1 in standard solutions). The modular workflow was validated by analyzing 24 blank and spiked buckwheat cereal samples with 5 and 10 μg kg-1 atropine. A cutoff value was established with an estimated false negative rate of 1% and estimated false positive rate of 0.68%. Therefore, the modular workflow can aid in fast, inexpensive, and on-site atropine detection by nonexperts, and when integrated with a scopolamine-specific icLFIA expanded toward scopolamine detection. Moreover, the developed sample extraction and concentration method (PI-LPME) is suitable for the analysis of many other compounds with pH-dependent polarity.

An efficient ultrasound vibration strategy for suppressing intra-bundle pores and regulating pore morphology in carbon fiber-reinforced composites

The competitive resin flow between intra- and inter-bundles, always causes the generation of intra-bundle pores during resin transfer molding (RTM), thereby weakening composite mechanical performance. Accordingly, an ultrasound vibration strategy is originally developed to efficiently suppress and improve the spatial morphology and distribution of intra-bundle pores in RTM manufacturing. The effects of ultrasound vibration on the spatial evolution of intra-bundle pores are systematically investigated, furthermore, the suppression mechanisms of intra-bundle pores are revealed. Additionally, an empirical model that predicts porosity under ultrasound vibration, is established and well validated for the developed ultrasound vibration strategy, which provides a feasible path for effectively manufacturing composites. X-ray micro-computed tomography experiments verify that applying a short period of ultrasound vibration balances the dual-scale flow by regulating the modified capillary number, thereby significantly reducing porosity by up to 59.4 %. Numerical analyses indicate that the acoustic cavitation and acoustic flow induced by the ultrasound vibration, facilitate the collapse and transverse migration of larger bubbles, thereby remarkably suppressing the connected pores and larger pores. In particular, the ultrasound vibration strategy completely removes the pores larger than 300 μm. Besides, the collective effects of vibration, compression, and shear forces contribute to forming near-circular pores, which are beneficial for ensuring the expected mechanical performance of composites.

B-262 Validation of a point-of-care lateral flow immunoassay for urine drug testing prior to application in an outpatient rapid access addiction medicine clinic

Abstract Background Point-of-care (POC) urine drug testing is a useful adjunct to self-reporting in rapid access addiction medicine settings to immediately guide patient management. However, available POC immunoassays have limitations including cross-reactivity with unrelated compounds or low sensitivity that may cause false results. Here, we assessed the performance of a multi-drug test panel by comparing against gold-standard liquid chromatography tandem mass spectrometry (LC-MS/MS) testing. Methods 102 residual urine specimens were assayed using a competitive lateral flow immunoassay (LFA) for 10 drugs: 2-ethylene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP, methadone metabolite), buprenorphine, morphine, hydromorphone, oxycodone, fentanyl, cocaine, methamphetamine, amphetamine, and benzodiazepines (BTNX Rapid ResponseTM Multi-Drug Panel). Results were compared to those obtained by LC-MS/MS (n=67, 66%) or kinetic interaction of microparticles in solution automated immunoassay (KIMS) (Roche Diagnostics, n=35, 33%). Broad spectrum LC-MS/MS results were reviewed in entirety for discordant cases, particularly in false positives to identify the presence of any known cross-reacting compounds. Results Of 10 drugs evaluated, four demonstrated ≥95% agreement with LC-MS/MS or KIMS immunoassay (EDDP, buprenorphine, oxycodone, methamphetamine). Fentanyl demonstrated the highest false negative rate of 44% (LFA cut-off: 10 ng/mL) followed by amphetamines (22%, cut-off: 1000 ng/mL). Morphine and hydromorphone demonstrated false positive rates of 14% and 18%, respectively, with most cases likely due to cross-reacting opiate or opioid metabolites. Benzodiazepines (target: Oxazepam) demonstrated false positive and negative rates of 13% and 24%, respectively. Conclusions To our knowledge, this is the first study to evaluate the performance of the BTNX multi-drug test panel against definitive testing in urine samples. While good concordance was observed for most drugs, high rates of discordant results for fentanyl and others emphasize the need for confirmatory testing by methods with higher sensitivity and specificity. Careful consideration prior to implementation would be essential, including physician education, interpretative comments, and training resources.

Can’t Stop, Won’t Stop Online In-Game Purchase on Mobile Phone: The Role of Flow Experience and Gaming Addiction (2024)

This study investigates factors influencing compulsive in-game purchases among Indonesian internet users, particularly Generation Z, and their societal impacts. It explores competitive behavior and flow experience in online gaming addiction, compulsive in-game purchases, and the link between them. Using quota sampling, 206 participants completed tailored questionnaires assessing online game addiction, flow, compulsive buying, and competitiveness. Structural equation modeling (PLS-SEM) was employed to analyze relationships between these constructs, revealing significant links between gaming addiction, flow experiences, and compulsive online purchasing. Competitive gaming may moderate the relationship between flow experience and compulsive buying.

Development of aptamer-based lateral flow devices for rapid detection of SARS-CoV-2 S protein and uncertainty assessment

The outbreak and spread of COVID-19 have highlighted the urgent need for early diagnosis of SARS-CoV-2. Nucleic acid testing as an authoritative tool, is cumbersome, time-consuming, and easy to cross-infect, while the available antibody self-testing kits are deficient in sensitivity and stability. In this study, we developed competitive aptamer-based lateral flow devices (Apt-LFDs) for the quantitative detection of SARS-CoV-2 spike (S) protein. Molecular docking simulation was used to analyze the active binding sites of the aptamer to S protein, guiding complementary DNA (cDNA) design. Then a highly efficient freezing strategy was applied for the conjugation of gold nanoparticles (AuNPs) and DNA probes. Under optimal conditions, the linear range of the constructed Apt-LFDs was 0.1–1 μg/mL, and the limit of detection (LOD) was 51.81 ng/mL. The cross-reactivity test and stability test of the Apt-LFDs showed good specificity and reliability. The Apt-LFDs had recoveries ranging from 89.45 % to 117.12 % in pharyngeal swabs. Notably, the uncertainty of the analytical result was evaluated using a “bottom-up” approach. At a 95 % confidence level, the uncertainty report of (453.37±54.86) ng/mL with k = 2 was yielded. Overall, this study provides an important reference for the convenient and reliable detection of virus proteins based on LFDs.

Periodic motions of species competition flows and inertial manifolds around them with nonautonomous diffusion

Periodic motions of species competition flows and inertial manifolds around them with nonautonomous diffusion

Competitive flow of bilateral internal thoracic artery Y-graft: Insights from hemodynamics and transit time flow measurement parameters

Recent studies have demonstrated the superior efficacy of bilateral internal thoracic artery (BITA) grafts compared to other graft methods in treating coronary artery disease. Competitive flow (CF) is a primary factor contributing to graft failure in the long term. For the first time, the CF of the BITA-Y graft has undergone rigorous numerical analysis. Through the application of transit time flow measurement (TTFM) and hemodynamic parameters, this study provides a new perspective on graft performance. Simulation results indicate that average flow, TTFM, and hemodynamic parameters fall within the critical range for stenosis severities below 90%. Specifically, at 80% stenosis, the mean graft flow (MGF) and pulsatility index (PI) of the left internal thoracic artery (LITA) were 0.071 cc/s and 27, respectively, while those of the right internal thoracic artery (RITA) were 0.211 cc/s and 11. With increasing stenosis severity, TTFM parameters remained within the clinical permissible limit (MGF > 0.34 cc/s and PI < 5). At 95% stenosis severity, the MGF and PI for LITA were 0.526 cc/s and 1.2, respectively, while those for RITA were 0.790 cc/s and 0.9. The results indicate the presence of competitive flow within the BITA-Y graft for stenosis severities below 90% area reduction, suggesting a potential risk of graft failure in the long term. Additionally, the results indicated that when there are significant differences in stenosis severity between the two native arteries, the BITA-Y graft is not optimal due to CF, characterized by low MGF and high reverse flow.

Prediction of functional coronary stenosis by computed tomography–derived fractional flow reserve in surgical revascularization

ObjectivesThe aims of this study were (1) to compare computed tomography–derived fractional flow reserve (CT-FFR) values with graft patency and (2) to establish the cut-off value of CT-FFR for predicting competitive graft flow after coronary artery bypass grafting (CABG). MethodsOf the 77 patients who underwent isolated CABG with an in situ internal thoracic artery (ITA)-based composite graft and who were also evaluated by preoperative cardiac CT, CT-FFR values were obtained in 74 patients. Early postoperative angiograms were performed in all 74 patients. Angiograms were performed to evaluate the grafts as well as the native coronary arteries to find any competitive flow present. Postoperative angiographic findings of graft flow were categorized as perfectly patent, bidirectionally competitive, unidirectionally competitive, and occluded. Receiver operating characteristic curve analysis of preoperative CT-FFR values for predicting postoperative angiographic competition was performed, and cutoff values of CT-FFR and area under the curve were identified. ResultsIn total, 234 anastomoses were performed in 74 patients (median 3 [interquartile range, 2, 4] anastomoses per patient). Postoperative (median 1 [interquartile range, 1, 2] day) angiograms showed that 196 (83.8%) anastomoses were perfectly patent, 25 (10.7%) anastomoses were bidirectionally competitive, 12 (5.1%) anastomoses were unidirectionally competitive, and 1 (0.4%) anastomosis was occluded. Median CT-FFR values of the coronary arteries with perfectly patent, bidirectionally competitive, and unidirectionally competitive grafts were 0.658 (interquartile range, 0.500, 0.725), 0.809 (interquartile range, 0.789, 0.855), and 0.849 (interquartile range, 0.833, 0.865), respectively. The cutoff value of CT-FFR predicting competitive graft flow was 0.774 (sensitivity, 97.4%; specificity, 98.5% [area under the curve 0.977; P < .001]). ConclusionsThe diagnostic accuracy of CT-FFR for predicting competitive graft flow after CABG was high, and CT-FFR could be used as a guide for predicting functional coronary artery stenosis in surgical revascularization.

Anomalous right coronary artery managed with bypass and proximal ligation

BackgroundAn anomalous origin and inter-arterial course of the right coronary artery is a rare anomaly that can lead to sudden ischemic cardiac death if left untreated. We present a case of a patient with an anomalous right coronary artery originating from the left coronary sinus and an inter-arterial course that was managed with coronary artery bypass surgery using a suitable internal mammary artery conduit. The proximal right coronary artery was ligated to prevent competitive flow.Case PresentationA 69 year-old-male with a ten-year history of intermittent chest pain and dyspnea with a negative workup underwent a cardiac catheterization, which showed an anomalous right coronary artery (RCA) originating from the left coronary sinus, with an inter-arterial course between the ascending aorta and pulmonary artery, and approximately 70% narrowing of the proximal RCA. The patient underwent an on-pump coronary artery bypass using the right internal mammary artery (RIMA) as a conduit, with segment 2 of the RCA being the target. The proximal RCA was ligated. Intra-operatively, there were no signs of ischemia or arrhythmia. The patient was successfully taken off cardiopulmonary bypass and eventually discharged home.ConclusionSymptomatic anomalous origin of the right coronary artery with an inter-arterial course can be treated successfully with coronary artery bypass surgery with the internal mammary artery as a conduit. Ligation of the proximal right coronary artery is essential to minimize competitive flow through the bypass graft.

4D flow mapping in adult with congenital aortic arch interruption and asymptomatic bypass occlusion: competitive flow patterns.

4D flow mapping in adult with congenital aortic arch interruption and asymptomatic bypass occlusion: competitive flow patterns.

Competitive Flow of Terminal Anastomosis to Right Coronary Territory in “Y” Coronary Artery Bypass

BackgroundWe evaluated the prevalence and outcomes of competitive flow in the terminal right coronary artery (RCA) graft after coronary artery bypass grafting (CABG) with left internal thoracic artery–based Y-composite grafting at 1 year after CABG. MethodsWe enrolled 642 patients who underwent Y-composite graft–based off-pump CABG with in situ left internal thoracic artery between 2014 and 2022. All patients underwent early postoperative angiography, and 1-year postoperative angiography was performed in 81.2% (522/642) of patients. ResultsThe early occlusion rate of distal anastomoses with Y-composite graft was 2.1%. Competitive flow was observed in 69 of 642 anastomoses (10.7%). Multivariate analysis showed that the maximal degree of target vessel stenosis (odds ratio [OR], 0.909; 95% CI, 0.886-0.931; P < .001), maximal degree of non–terminal target vessel in Y-arm grafts (OR, 1.103; 95% CI, 1.047-1.172; P < .001), and diabetes mellitus (OR, 0.535; 95% CI, 0.303-0.934; P = .029) were factors associated with competitive flow to the RCA territory. The optimal cutoff value for the degree of terminal target vessel stenosis predicting competitive flow to the RCA territory was 92.5%. The 1-year graft failure rate of anastomoses with competitive flow of the terminal anastomosis was 30.9% (17/55). The presence of competitive flow on early angiography was the only factor associated with graft occlusion of the terminal anastomosis at 1 year (OR, 2.339; 95% CI, 1.165-4.481; P = .013). ConclusionsFor terminal anastomosis to the RCA territory in Y-composite graft–based CABG, the presence of competitive flow on early angiography was associated with graft occlusion of the terminal anastomosis at 1 year. Notably, 30.9% of these grafts demonstrated failure on 1-year follow-up angiography.

Validation of the AgraStrip® Pro Total Aflatoxin WATEX® Method for Detection of Total Aflatoxins in Corn and Peanut Paste: AOAC Performance Tested MethodSM 032402.

To protect public and animal health against risks provoked by aflatoxins contained therein, maximum limits for aflatoxins are defined. Limit values vary depending on the intended use and regulatory authority, therefore quantitative detection is essential. Validation of a one-step competitive lateral flow immunochromatographic assay for quantitative screening of total aflatoxin (B1, B2, G1, and G2) in corn and peanut paste for the high-sensitivity range (0-50 µg/kg). Corn or peanut paste test portions are water-based extracted and prepared for testing within 15 min. The AgraStrip® Pro Total Aflatoxin WATEX® test method quantifies the concentration of aflatoxins in the sample. Selectivity, robustness, product consistency, and stability testing were performed in addition to matrix testing. No cross-reactivity was detected against possible interferants. Corn resulted in a LOD and LOQ of 0.9 and 2.8 µg/kg and overall recoveries between 74 and 108%. Peanut paste resulted internally in a LOD and LOQ of 0.8 and 2.3 µg/kg and recoveries between 86 and 98%. Stability testing showed no influence of the age of the respective lot on the result. Robustness testing demonstrated that varying the amount of water used for extraction, extraction time, and delay between extract dilution and analysis did not significantly affect the result. Due to supply chain issues, a change to the outer cartridge required an increase in the test aliquot size, which had no effect on method performance. The test kit was validated for the determination of total aflatoxins in corn and peanut paste. Recovery and precision met the requirements laid down in Codex Alimentarius CXG 71-2009 and acceptable robustness, selectivity, and product consistency and stability were demonstrated. The AgraStrip Pro Total Aflatoxin WATEX test kit in the high sensitivity range (0-50 µg/kg) was approved by the AOAC AOAC Research Institute (PTM number 032402).

Effect of competitive flow and diltiazem on postoperative hemodynamics and long term patency rate after coronary artery bypass grafting

Effect of competitive flow and diltiazem on postoperative hemodynamics and long term patency rate after coronary artery bypass grafting

Joint facial action unit recognition and self-supervised optical flow estimation

Facial action unit (AU) recognition and optical flow estimation are two highly correlated tasks, since optical flow can provide motion information of facial muscles to facilitate AU recognition. However, most existing AU recognition methods handle the two tasks independently by offline extracting optical flow as auxiliary information or directly ignoring the use of optical flow. In this paper, we propose a novel end-to-end joint framework of AU recognition and optical flow estimation, in which the two tasks contribute to each other. Moreover, due to the lack of optical flow annotations in AU datasets, we propose to estimate optical flow in a self-supervised manner. To regularize the self-supervised estimation of optical flow, we propose an identical mapping constraint for the optical flow guided image warping process, in which the estimated optical flow between two same images is required to not change the image during warping. Experiments demonstrate that our framework (i) outperforms most of the state-of-the-art AU recognition methods on the challenging BP4D and GFT benchmarks, and (ii) also achieves competitive self-supervised optical flow estimation performance.