Dye Deposition Research Articles

Ultrasound-guided celiac plexus block increases intestinal motility in normal horses.

To describe a technique for ultrasound-guided celiac plexus block in horses and characterize its effect on intestinal motility in healthy horses. This study was conducted from January 2022 through June 2022. In phase 1 (dye study), an ultrasound-guided technique was optimized, and dye deposition around the celiac plexus branches was evaluated via postmortem dissection in 6 horses. In phase 2 (experimental study), 6 healthy horses were fasted and sedated with 0.6 mg/kg xylazine, IV (experiment 1). After a washout period, the ultrasound-guided celiac plexus block with lidocaine 1% (1.3 mg/kg) was performed after sedation (experiment 2). In both experiments, intestinal motility was recorded via transcutaneous ultrasound before sedation, after sedation (15, 30, and 45 minutes and 1, 2, 3, 4, and 6 hours), and 1 hour after refeeding. Ultrasound video recordings were blinded of horse identity, day, and time; randomly arranged; and scored using a specifically designed motility scoring system. Postmortem dissection confirmed dye deposition over the celiac plexus branches. In phase 2, a significant increase in intestinal motility was detected after the celiac plexus block compared to sedation alone, with a peak between 1 and 3 hours postblock (13.58 ± 2.8 vs 3.75 ± 2.4 at baseline); motility remained increased up to 6 hours. The only side effect observed was a transient hindlimb ataxia in 1 horse. Ultrasound-guided celiac plexus block is feasible and induces an increase in intestinal motility in healthy horses without significant complications. This technique can be considered in multimodal management of colic and paralytic ileus.

A method to spatially assess multipass spray deposition patterns via UV fluorescence and weed population shifts

AbstractSpray deposition patterns from agricultural sprayers are traditionally sampled discretely along a field transect accounting for 0.5% or less of the treated area. Such methods may not fully capture the dimensional variability inherent in large‐scale, multiple‐pass spray applications, especially evident from an agricultural spray drone (ASD). This study investigated the utilization of UV‐fluorescent dye and nighttime aerial imaging techniques to assess large‐scale, multipass spray deposition patterns. Accuracy of digital hue from UV‐fluorescent photography to predict deposition of proxy dye was confirmed via fluorometry assessed intensity levels of extracted UV‐fluorescent dye from 384 Petri dishes placed prior to treatment. Results showed that ASD applications, regardless of nozzle type, exhibited greater spatial variability within the target area compared to ride‐on sprayer applications, primarily due to overapplication. Additionally, the ASD generated spray drift to adjacent nontarget areas that was at least three times more than that of ride‐on and spray‐gun sprayers. Multipass deposition was further assessed via in situ smooth crabgrass infestation following treatment with quinclorac or topramezone by multipass ASD or hand‐held, four‐nozzle spray boom. Weed infestation annotated from overlaid grids with 9.3‐dm2 ground resolution inconsistently detected spatial heterogeneity between transects assessed along the center and edge of each sprayer pass. The ASD controlled smooth crabgrass 11% more than the hand‐held sprayer, albeit with an 18% increase in spray drift to nontarget areas, similar to the UV‐fluorescence study. Digitally assessed average hue of fluorescence photography appears to be a viable method to assess multidimensional and continuous spatial relationships of spray deposition.

Fabrication of charged and zwitterionic nanofiltration membranes and anti-adhesion analysis using quartz crystal microbalance with dissipation and atomic force microscopy

Three nanofiltration (NF) membranes (positive charge, negative charge and near charge neutrality) were fabricated to investigate the anti-adhesion mechanism. Among them, the NF membrane with positive charge was synthesized through an electrophilic substitution reaction between the amino group of polyethyleneimine (PEI) and the chloromethyl groups of chloromethyl polysulfone (CMPSf) on a supporting polysulfone (PSf)/CMPSf blend membrane. The NF membrane with negative charge was fabricated through polycondensation using 1, 3, 5-benzenetricarbonyl trichloride (TMC) as a reactive monomer on the positive charge NF membrane. Subsequently, the near charge neutral zwitterion NF membrane (ZNF) was prepared by grafting 3-((2-aminoethyl) dimethylammonio) propane-1-sulfonate (sulfobetaine) (ADSS) onto the negative charge NF membrane. The anti-adhesion behaviors of the NF membranes during the dye selective separation were analyzed by Atomic force microscopy (AFM) and quartz crystal microbalance with dissipation (QCM-D). The results demonstrated that the near charge neutral ZNF membrane displayed a higher dyes rejection (>94.4 %) and higher flux recovery rates (>88.1 %) than charged NF membranes. Meanwhile, the near charge neutral ZNF membrane demonstrated the lowest amounts of dye deposition compared with charged NF membranes, such as reactive blue 4 (R4) for 509.9 ng/cm2, basic blue 24 (BB 24) for 269.0 ng/cm2, rhodamine B (RB) for 197.4 ng/cm2). Additionally, the near charge neutral ZNF membrane with the thicker hydration layer (121.7 nm) displayed weaker interaction forces (−4.8 nN to −7.4 nN) with the dyes than the charged membranes (−10.4 nN to −28.6 nN). Finally, an anti-adhesion mechanism involved charged shielding effect and hydration layer formation was proposed. These observations provide comprehensive insights into the anti-adhesion mechanism of ZNF membrane.

On-Target Deposition from Two Engine-Powered Sprayers in Medium-Foliage-Density Citrus Canopies

Spray penetration into citrus canopies is critical for adequate coverage and deposition to ensure effective pest control. However, mismatch of air assistance to target canopy characteristics can lead to unintended spraying losses through overpenetration. To evaluate the effect of air assistance on on-target deposition, two sprayers (surrogates for airflow rates) were used to apply a fluorescent tracer dye solution @ a target concentration of 300 ppm to 16 medium-foliage-density tree blocks in a commercial mandarin orchard. The complete factorial experiment in three replications, also designed for validating a model-based spray decision support tool, comprised two forward travel speeds (1.6 and 4.8 km/h), two disc-core nozzles (TeeJet® D3-25 and D6-45), and either one or two nozzle rows to obtain a wide range of application rates (496 to 9719 L/ha). Dye deposition significantly decreased with canopy depth (p =< 0.001) by nearly seven times across the 3.4 m wide canopies but was not significant over 1.2 to 2.2 m sampling height (p = 0.867). Deposition obtained with the low-airflow-rate sprayer was significantly greater (p =< 0.001) than that obtained with the high-airflow-rate sprayer over the dose range likely due to too much air pushing out spray droplets. This study underscores the importance of matching the air assistance of orchard sprayers to the target canopy.

Refinement of intranasal delivery in rats: A cadaveric study.

The intranasal route enables direct delivery of multiple substances from the nose to the brain, through olfactory and trigeminal pathways, bypassing the blood-brain barrier and avoiding systemic absorption. Despite the potential of this route, the various administration approaches make data reproducibility and interpretation challenging, emphasizing the necessity to establish a consistent methodology. Considering this, the aim of our study was to assess and compare the distribution of two dye volumes (30 µl and 50 µl) in the nasal cavity of rat cadavers. We employed three distinct methods of intranasal delivery: nose drops, by pipette tip, or cannula inserted into the nasal cavity. The results indicated that for both volumes, using the nose drops and the pipette tip methods, the dye dispersion occurred mainly in the vestibule, respiratory and olfactory regions, without reaching the olfactory bulbs. Using the cannula method, the deposition predominantly occurred in the respiratory and olfactory regions, with the dye reaching 66.7% and 100% of the olfactory bulbs, respectively, to low and high volume. Furthermore, the results demonstrated differences between the two volumes, in the pharynx, larynx, trachea, septal window, and incisive papilla, where an increased dye presence was observed with the 50 µl instillation across all three methods. According to our results, the intranasal delivery with a cannula was the most effective method for dye deposition in the olfactory region. However, further studies in live animals will be necessary to determine and refine the administration method that consistently allows specific deposition in the olfactory system.

Electrochemical visualization of latent fingerprints using polyphenazine dyes on brass cartridges

This work is focused on the visualization of latent fingerprints left on unfired brass cartridges. Polymer films were prepared from 2 mM neutral red or 5 mM toluidine blue using two different electrochemical methods (cyclic voltammetry or chronoamperometry) with relatively short polymerization times. The conditions for the deposition of conductive polymers, poly(neutral red) and poly(toluidine blue), from a neutral medium (phosphate buffer with 0.1 M KNO3 or 0.1 M KNO3, respectively) were optimized to produce high-quality visualization of the remaining fingerprints on the brass substrates. The surface morphology and quality of the polymer films after the electrochemical deposition of both polyphenazine dyes were characterized by stereomicroscope. Phenazine dyes, which were used for the visualization of fingerprints, have been shown to provide different degrees of homogeneity in the deposited film. Furthermore, the dependence of the stability of the monomer solutions on their age, use, and storage conditions are discussed. Finally, a methodology is proposed for how to apply this technique of visualizing latent fingerprints with observed details of papillary lines in forensic practice.Graphical abstract

Boosting DSSC efficiency via acid-base co-sensitization with N-1 dye

This work presents a comprehensive investigation of a novel organic dye, N-1, as a sensitizer and co-sensitizer in dye-sensitized solar cells (DSSCs) co-sensitized with Ru (II)-based N3 and N719 metal dyes. These co-sensitizers contain a carbazole ring as a donor scaffold linked to an electron-withdrawing pyridyl acceptor. In this study, we demonstrate the significant impact of a base dye (N-1) containing a pyridine anchoring unit on the photovoltaic performance of the standard dyes N3 and N719. This strategy takes advantage of the capacity of the carboxylic and pyridine moieties to attach to the Brønsted-acidic and Lewis-acidic positions of TiO2 interfaces, thereby diminishing the competing adsorption of dyes and augmenting dye deposition on TiO2 surfaces. Consequently, this leads to a reduction in electron recombination and a boost in photovoltage. Additionally, the effect of sensitizer/co-sensitizer concentration on device performance was thoroughly examined. The results indicated that devices fabricated using the co-sensitizer N-1 with sensitizers N3 and N719 at all concentrations outperformed N3 and N719. Notably, the best photovoltaic performance was obtained for the co-sensitized device fabricated using 0.3 mM acid-base N-1 along with N3 sensitizer, displaying a power conversion efficiency of 10.18 % with a short-circuit current density of 19.12 mA.cm−2, open-circuit voltage of 750 mV, and fill factor of 71 %. These findings shed light on the development of new and efficient systems for DSSCs.

Rapid adsorptive removal of eosin yellow and methyl orange using zeolite Y

In this study, zeolite Y was synthesised using a novel method. The heat generated from the reaction of H2SO4 with metakaolin was used as a heat source instead of applying external heat for the dealuminated process. The synthesised zeolite Y produced was analysed by scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier-infrared spectroscopy (FTIR), energy dispersive X-ray spectroscopy (EDS) and Brunauer–Emmett–Teller (BET). Zeolite Y synthesis was mesoporous because of its pore diameter (30.53 nm), as shown in the BET results. Surface area and pore size decrease after adsorption due to dye deposition on the adsorbent’s surface. FTIR has bonds like O–H, C–H, –CH3, and –COOH responsible for adsorption. The maximum adsorption capacity of eosin yellow (EY) and methyl orange (MO) on to zeolite Y by the Langmuir isotherm was 52.91 mg/g and 20.62 mg/g respectively, at pH 2.5 and 8 for EY and MO dye. The batch adsorption studies were conducted, and the influence of different parameters (i.e., adsorbent dose, adsorption time, initial dye concentration, pH and temperature) was investigated. Experimental data were analysed by two linear model equations (Langmuir and Freundlich isotherms), and it was found that the Langmuir isotherm model best describes the adsorption data for methyl orange and Freundlich isotherm for eosin yellow, respectively. Adsorption rate constants were determined using linear pseudo-first-order and pseudo-second-order. The results showed that MO and EY dye adsorption onto zeolite Y followed a pseudo-second-order kinetic model. Thermodynamic studies show that adsorption was an exothermic reaction (enthalpy < 0) and feasible ((Gibbsfreeenergy)<0\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$(Gibbs free energy)<0$$\\end{document}) at various temperatures under investigation.

Assessment of textile industry effluent (untreated and microbially treated) induced genotoxic, haematological, biochemical, histopathological and ultrastructural alterations in fresh water fish Channa punctata.

The unregulated expulsion of untreated textile water into water bodies is a major hazard to aquatic ecosystems. The present investigation was contrived to estimate the impact of textile dye bath effluent (untreated and microbially treated) on fish Channa punctata. Untreated effluent-exposed fish showed extremely altered behaviour (air gulping, erratic and speedy movements, increased opercular activity) and morphology (deposition of dyes on skin and scales, high pigmentation, mucus exudation). Significantly increased micronuclei (1.61-, 1.28-, 1.38-fold) and aberrant cell frequency (1.37-, 1.45-, 1.28-fold) was observed in untreated group as compared to treated group after 15, 30, and 45 days of exposure. Tail length, % tail intensity, tail moment and olive tail moment were also enhanced in all the exposed tissues. However, maximum damage was noticed in gill tissues showing 1.19-, 1.37-, 1.34- and 1.50-fold increased TL, %TI, TM and OTM in untreated group as compared to treated group after 45 days of exposure. On comparing untreated and treated groups, increased blood parameters and significantly reduced white blood cell count (WBC) were noticed in treated group. Significantly enhanced alterations in biochemical parameters were also analysed in untreated group. Reduced alterations in enzymological levels of fishes exposed to treated effluent indicate lesser toxic nature of the degraded metabolites of dye. Histological analysis in fishes exposed to untreated effluent showed several deformities in liver (necrosis, congestion, fusion of cells and melanomacrophage infiltration) and gill tissues (necrosis, bending of lamellae and severe aneurysm). Scanning electron microscopy (SEM) analysis further reaffirmed the pathologies observed in histological analysis. Fewer structural alterations were noticed in treated effluent fishes. The results concluded that untreated effluent inflicted toxicity potential on morphology as well as physiological defects in fish, and the severity increased with increasing duration of exposure, whereas reduction in toxicity in microbially treated groups can be analysed for aquacultural purposes owing to their lesser toxic nature.

Investigation of a maxillary nerve block technique in guinea pigs (Cavia porcellus): A cadaveric study comparing two injectate volumes

ObjectiveTo investigate and describe an extraoral approach to perform a maxillary nerve block in guinea pigs. Study designProspective, randomized, blinded, descriptive, cadaveric study. AnimalsA total of 14 adult guinea pig cadavers. MethodsTwo cadavers were used for anatomic dissection and determination of maxillary nerve block approach. A maxillary nerve block via infraorbital approach was then performed in 12 cadavers. A low volume (0.1 mL) or high volume (0.2 mL) of diluted methylene blue injectate was randomly assigned to the right or left side, with the other volume used for the contralateral side. The maxillary nerve was dissected after each injection by an investigator blinded to injectate volume. The region of dye distribution was identified, and the degree of staining assigned an accuracy score (0–2). Nerve coverage was considered adequate if ≥6 mm of circumferential staining was present. ResultsAccuracy evaluation indicated successful dye deposition in 10/12 [2 (0–2), median (range)] injections in the low volume group and 8/12 [2 (1–2)] injections in the high volume group. The majority (79.2%) of injections resulted in adequate nerve staining. There were no statistically significant differences between injectate volumes for accuracy (p = 0.64) or adequacy (p > 0.99) of staining. ConclusionsThe infraorbital approach is a simple and practical method for maxillary nerve blockade in guinea pigs. An injectate volume of 0.1 mL results in adequate maxillary nerve coverage; however, additional studies are needed to assess the efficacy in clinical use.

Simple adsorptive removal of crystal violet, a triarylmethane dye, from synthetic wastewater using Fe (III)-treated pine needle biochar.

Untreated and Fe (III)-treated pine needle biochar (PNB) were evaluated at different pH for the removal of toxic crystal violet (CV) dye from synthetic wastewaters. Adsorption kinetics followed the pseudo-first-order kinetics involving intra-particle diffusion process. The adsorption rate constant increased with Fe treatment of PNB especially at pH 7.0. Adsorption data of CV conformed well to Freundlich adsorption isotherms and both adsorption capacity (ln K) and order of adsorption (1/n) of CV were nearly doubled with Fe (III) treatment of PNB at pH 7.0. Desorption of adsorbed CV from both untreated and Fe (III)-treated PNB could be accounted satisfactorily by third-degree polynomial equations. An increase in ionic strength and temperature enhanced dye adsorption onto untreated and Fe (III)-treated PNB. Adsorption of CV was an endothermic and spontaneous reaction with an increase in entropy of the system. FTIR spectra revealed that C = O of carboxylic acid aryls and C = O and C-O-C in lignin residues of PNB reacted with Fe (III) besides the formation of some iron oxyhydroxide minerals. The changes in FTIR confirmed the possible bonding of positively charged moiety of CV with the untreated and Fe-treated PNB. Scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) revealed the porous surfaces of PNB with clear accumulation of Fe (III) after treatment and deposition of CV dye on surfaces and pores of PNB. Iron (III)-treated PNB at pH 7.0 can serve as an ecofriendly and cost-effective adsorbent for the efficient removal of CV dye from wastewaters.

Histological Effects of Aqueous Extract of Saffron Flowers Crocus sativus on Ovaries and Oviduct of Females White Mice Mus musculus

The present study was conducted to identify the histological effects of the aqueous extract of saffron flower on ovaries and oviducts of the adult female mouse at doses of 15, 30 and 60 mg/kg of body weight (b.w.).for the periods 7,15 and 30 days, respectively and once a day. Behavioral changes were include the abnormal hyperactivity, irritability followed by introversion and reduction of motor activity, as well as loss of appetite for food and drinking water for several hours. The results showed histopathological changes of mice ovaries at a dose of 15 mg /kg of B.W. for the above periods a slight increase in primordial follicles, congestion of blood vessels, necrosis and degeneration. At a dose of 30 mg/kg. there was slight deposition of hyaline material, deposition of hemosiderin dye, congestion and increase of primordial follicles numbers, while at a dose of 60 mg/kg lymphatic cells infiltration were observed, with some ovarian stromal cells decaying. while the oviduct, and for the above periods changes included thickening of canal wall, endothelial cells degeneration and blood vessel congestion in the muscular area at a dose of 15 mg/kg, increased flattening of the mucosal folds also was observed. At a dose of 30mg /kg. an increased damage with increased blood vessels congestion, fibrosis of oviduct wall and degeneration of the external muscle layer of the oviduct at a dose of 60 mg /kg was obvious.

Porphyromonas gingivalis bacteremia increases the permeability of the blood-brain barrier via the Mfsd2a/Caveolin-1 mediated transcytosis pathway

Bacteremia induced by periodontal infection is an important factor for periodontitis to threaten general health. P. gingivalis DNA/virulence factors have been found in the brain tissues from patients with Alzheimer’s disease (AD). The blood-brain barrier (BBB) is essential for keeping toxic substances from entering brain tissues. However, the effect of P. gingivalis bacteremia on BBB permeability and its underlying mechanism remains unclear. In the present study, rats were injected by tail vein with P. gingivalis three times a week for eight weeks to induce bacteremia. An in vitro BBB model infected with P. gingivalis was also established. We found that the infiltration of Evans blue dye and Albumin protein deposition in the rat brain tissues were increased in the rat brain tissues with P. gingivalis bacteremia and P. gingivalis could pass through the in vitro BBB model. Caveolae were detected after P. gingivalis infection in BMECs both in vivo and in vitro. Caveolin-1 (Cav-1) expression was enhanced after P. gingivalis infection. Downregulation of Cav-1 rescued P. gingivalis-enhanced BMECs permeability. We further found P. gingivalis-gingipain could be colocalized with Cav-1 and the strong hydrogen bonding between Cav-1 and arg-specific-gingipain (RgpA) were detected. Moreover, P. gingivalis significantly inhibited the major facilitator superfamily domain containing 2a (Mfsd2a) expression. Mfsd2a overexpression reversed P. gingivalis-increased BMECs permeability and Cav-1 expression. These results revealed that Mfsd2a/Cav-1 mediated transcytosis is a key pathway governing BBB BMECs permeability induced by P. gingivalis, which may contribute to P. gingivalis/virulence factors entrance and the subsequent neurological impairments.

Новый фотоанод на основе иерархически структурированного двойного оксида Ti–P

A new electricity source is a hot topic for material scientist working for the development of a new reliable, stable and green generation of energy. An exponential growth of the energy consumption in the last few decades raised the concerns about limitations of the conventional energy supply, let alone ecological problems. A considerable effort has been made by scientific community to meet the challenge of the efficient conversion of the sunlight to the electricity. Widespread application of the photovoltaic panels lowered the greenhouse burden in developed countries. Simultaneously, a significant momentum was given to the so-called 3rd generation photovoltaics, based on the highly efficient organic dyes, deposited on the photoanodes. Such photoanodes must meet a set of requirements: high porosity, for increased deposition of the organic dye, and a developed network of the charge draining channels for efficient charge transfer to the photoanode. An emergence of a novel hierarchically structured materials helped to meet abovementioned demands and created a solid ground for advanced photovoltaics. In this work, we test a novel hierarchically structured Ti–P double oxide as a dye-deposition substrate for photoanode as a perspective material for 3rd generation of photovoltaics. Preliminary results prove novel structures are efficient, yet need practical modifications.

Effect of air blast sprayer application speed on the dye retention of coffee leaves

Improving the effectiveness of pesticide application for controlling insects, mites, and pathogens in coffee cultivation has been a major challenge for coffee farmers, researchers, and consultants. The present study aimed to assess the deposition and distribution of a brilliant blue tracer in the coffee canopy using Jacto’s Arbus 2000 Super Export EL and Kuhn’s Twister 2000 air blast sprayers at different application speeds (5 and 7 km h-1). The experiment was conducted using a randomized block design, with a 2 × 2 factorial arrangement (two sprayer models and two application speeds), with six replicates. After spraying, leaves were collected, and the deposition of the tracer was assessed using spectrophotometry. The canopy was divided into lower, middle, and upper heights, and subdivided into external and internal crown positions. The percentage difference in spray deposition between positions was termed relative spray deposition. Spray deposition in the internal crown differed only in the upper third section between sprayers. In the external crown, the application speed affected the deposition of tracer dye for both sprayers, whereas, in the internal crown, the application speed only affected the deposition of tracer dye in the upper crown section only when using the Arbus sprayer.

Assessment of Spray Drift with Various Adjuvants in a Wind Tunnel

When pesticides are sprayed, a significant portion of the droplets drifts away from the target. Using an adjuvant in spray liquid is an easy option for reducing droplet drift because there is no need to make any changes to the sprayer. The objective of the study was to determine the effects of seven commercially available adjuvants (Surfeco plus, Starguar, Kantor, Sterling, Control, Control WM, and Control DUO) with varying active ingredients on droplet size, surface tension, and viscosity. Since these properties affect droplet formation, these adjuvants were evaluated in terms of their drift-reducing performance in a wind tunnel at various wind speeds (2.0, 3.5, and 5.0 m/s) and spray pressures (3, 4, and 5 bars). The ground and airborne components of drift were evaluated. With the use of a patternator, the potential for the ground drift of adjuvants was measured; for airborne drift, polyethylene lines that were stretched along the cross-section area of the wind tunnel at various heights were employed. The number of deposits of a tracer dye–adjuvant mixture that was sprayed on the polyethylene lines was measured via fluorometric methods for determining the airborne drift potential. The test results showed that the adjuvant Control Duo containing a polymer blend, which had the highest dynamic viscosity (4.27 mPa.s), increased the Dv0.5 droplet diameter up to 192 μm at 3 bar with nozzle XR11002. This adjuvant reduced the ground drift potential (Dc) by 60.53% compared to tap water. The maximum airborne drift potential reduction percentage (DPRP) was obtained as 85.76% with Surfeco plus containing organic silicone at a pressure of 3 bar and a wind velocity of 5 m/s. When considering the airborne drift-reduction potential of the adjuvants used, it was found that the adjuvants Control WM, Control, Starguar, and Surfeco plus significantly reduced the airborne droplet drift compared to spraying tap water.

Abstract 1726: Novel, high-throughput multiplexed immunofluorescence staining method for assessing spatial relationships of immuno-oncology biomarkers in whole slide FFPE tissue

Abstract As cancer research has progressed, the role of the immune system in tumor development has been discovered to be increasingly more important. There is a need to explore the spatial relationships between tumor and immune cells in tissue to help better predict therapeutic treatment outcomes in patients in the growing field of immuno-oncology. We have developed a new single cell multiplexed immunofluorescence staining method along with our patented multi-spectral imaging (MSI) technology to allow scientists to detect up to six biomarkers simultaneously on one tissue section, which provides an end-to-end, fully automated workflow from staining to image analysis. In this study, we show a methodology that allows primary antibodies to be applied as a single cocktail in one incubation step followed by amplified detections using Opal fluorescent dye technology. Formalin-fixed paraffin-embedded (FFPE) samples were stained on the Leica BOND RX࣪ automated staining system using our new multiplex procedure and compared to 3,3′-Diaminobenzidine (DAB) chromogenic immunohistochemistry assay. Multispectral scans were acquired on the Akoya Vectra Polaris® imaging system with optimized acquisition parameters. Image analysis was performed with a phenotyping algorithm in inForm® analysis software and intensity analysis was performed in R using phenoptr and phenoptrReports. The six multiplexed biomarkers are shown to be comparable in staining patterns to their DAB counterparts. Whole slide image scans were successfully unmixed and treated as individual monoplexes, but combined at will to observe the spatial relationships. This easy-to-use staining method simplifies tissue-based multiplex immunofluorescence by providing primary antibody cocktailing and cyclic deposition of fluorescent Opal dyes while maintaining strong staining intensity and the ability to spectrally unmix different wavelengths from the image for visualization and spatial analysis. This novel method will provide researchers with a flexible and readily available solution for staining patient samples to investigate spatial phenotypic signatures, aiding in the development of targeted immune therapies. Citation Format: Rachel Schaefer, Linying Liu, Michael McLane, Oscar Perez, Jacob Circelli, Carla Coltharp, Yi Zheng. Novel, high-throughput multiplexed immunofluorescence staining method for assessing spatial relationships of immuno-oncology biomarkers in whole slide FFPE tissue [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1726.

Configuration and Assessment of a Submersible Fluorometer for Evaluating Fluorescent Dye Deposition

Abstract Fluorescent tracer dyes are popularly used in agricultural spray application studies to evaluate on-target canopy deposition and off-target drift, and the methods/instruments used for evaluating dye deposit must assure reliability of the data generated. A laboratory setup was configured to adapt a submersible fluorometer for controlled and reliable measurement of pyranine dye fluorescence in liquid samples. The system setup was blanked using a clean sample of de-ionized water and calibrated using standard dye solutions of known concentration (100 to 1,000,000 parts per trillion [ppt]) made from two dyes of different levels of purity (pyranine 98 % and pyranine 85 %). Pyranine 85 % fluorescence readings were consistently lower with reduction factor averaging ∼0.62 times that of pyranine 98 % within a range from 500 to 1,000,000 ppt. The results were verified using a standard laboratory fluorometer. Spray deposition assessment of string, plastic card, cotton ribbon, and artificial foliage samplers was accomplished using the configured fluorometer system setup. The results showed no significant difference among dye purity levels (P = 0.430), no statistically significant interaction between dye purity and concentration (P = 0.484), and no statistically significant interaction between dye purity and sampler type (P = 0.173). Consequently, the configured setup can produce measurements with similar quality as the standard laboratory fluorometer and both dyes tested may be equally used for spray deposition and drift assessments, or for similar applications.

Membrane distillation for the recovery textile wastewater: Influence of dye concentration

The implementation of membrane distillation in the recovery of textile wastewater can minimize waste production to an industry segment that is a significant consumer of fresh water and one of the biggest polluters. This study investigated the influence of the dye's concentration in the performance of the direct contact membrane distillation process with a polytetrafluoroethylene membrane and synthetic solutions of reactive and disperse black dyes. Results demonstrated a decrease in the permeate flux as the dye concentration increased with the influence of the dye class. At the highest concentration tested (3000 mg·L−1) and compared to water, there was a reduction more accentuated for the disperse dye (41.4% - J = 15.13 kg·h−1·m−2 in 0 mg·L−1 and Jf = 5.09 kg·h−1·m−2) than for reactive dye (35.3% - J = 15.13 kg·h−1·m−2 in 0 mg·L−1 and Jf = 9.50 kg·h−1·m−2). On the other hand, color rejection results were above 98% with both dyes, even in high concentrations. The fouling factor was calculated, and the disperse dye presented higher values when compared to the same concentrations in reactive dye solutions, indicating that the physicochemical characteristics of the dyes influence the process. Dye deposition on the membrane surface was tested using SEM, EDX, contact angle, thickness, and FTIR analysis. The results indicated that the reactive dye confirmed less fouling than disperse black. The membrane presented good resistance to solutions with high concentrations. Based on these results, the process is viable and highly efficient for the production of recovered water, indicating the feasibility for continuously updated cleaner production.

Experimental study and numerical optimization for removal of methyl orange using polytetrafluoroethylene membranes in vacuum membrane distillation process

One of the most water-intensive and environment polluting anthropogenic industries is the textile industry. Amongst textile dyes, methyl orange (MO) is an extensively used anionic azo dye that is toxic to the environment. In this study, the effect of various process parameters was studied for different operating conditions (mass flow rate, vacuum pressure, inlet feed temperature, dye concentration) to remove MO from synthetic wastewater in the vacuum membrane distillation (VMD) process. We determined the optimum conditions for operating variables using response surface methodology (RSM) and developed a regression model to describe permeate flux, dye rejection and specific energy consumption. The optimum operating parameters from the RSM study were bulk feed temperature: 70 °C, mass flowrate: 40 kg h−1, dye concentration: 60 mg l−1 and vacuum pressure: 720 mm Hg. For the optimized input process parameters, the experimentally observed values were permeate flux: 19.60 ± 1.03 l m−2 h−1, dye rejection: 99.80 ± 0.07%, and SEC: 2.04 ± 0.11 kW h m−3. Furthermore, for these optimized conditions, a 3D CFD model was developed to gain insight into the membrane module's thermal, velocity, and concentration field. The evaporation of feed at the membrane surface on the feed side and condensation of vapours at the membrane surface on the permeate side was captured in this model. The permeate flux profile and dye rejection for various cycles of VMD operation with intermittent washing were also performed to study the fouling behaviour of the membrane. The membrane's surface fouling was analyzed using SEM and FT-IR analysis. The SEM analysis of the fouled membrane indicated that the dye deposition was not severe due to high hydrophobicity, high liquid entry pressure, and high pore wetting resistance of the PTFE membrane. The FT-IR analysis showed that the fouled PTFE membrane sufficiently retained its initial structure and property.