Rinse Time Research Articles

Analysis of Residual Tetraacetylethylenediamine Levels according to Rinsing Time of Denture Cleanser

Objective: Tetraacetylethylenediamine (TAED), a denture cleanser was reported to have a risk of acute side effects at high concentrations. This study evaluated residual TAED from denture cleansers after rinsing for different durations. Methods: The rinsing times of denture cleansers were investigated. Specimens made with the denture base-resin were immersed in a denture cleanser and rinsed with running water. The experimental groups were divided based on the rinsing time; G1 was rinsed for 10 s, G2 for 20 s, G3 for 30 s, and G4 for 60 s. No rinsing was performed in the control group. After the elution of TAED from the samples, quantification was performed using high-performance liquid chromatography and mass spectrometry. Results: Seven denture cleansers were investigated; however, the specific rinsing time was not confirmed. Conversely, the control group had a significantly higher amount of TAED (315.4±104.7 ㎍/L), whereas the other groups with > 10 s rinsing time showed significantly decreased residual TAED. Conclusions: To prevent the potential risks of TAED, users should rinse their dentures thoroughly for ≥ 10 s after using a denture cleanser.

Evaluation of Metal Contamination Behavior on Silicon Wafer Surfaces Rinsed with Deionized Water Containing pg/L-Level Impurities

Two tests were performed to investigate the contamination behavior of bare Si wafers by rinsing them using deionized water (DIW) contaminated with metals at the pg/L-level in a single-wafer cleaning process. First, we found that Al, Ti, Mn, Co, Cu, Sr, and Pb exhibited strong correlations between the metal concentrations in DIW and the wafer surface concentrations under different concentrations in DIW and the same rinse time of 480 min. Second, we observed that the wafer surface concentrations of Al, Ti, Cu, and Pb increased with the rinse time, whereas those of Mn, Co, and Sr were constant at rinse times ranging from 10 to 960 min at metal concentrations of 60 pg/L in DIW. In this test, Cu exhibited a high adsorption ratio on bare Si wafers, even at the pg/L level. These data provide novel insights into wet processes for device manufacturing.

Accelerated Fabrication of Fiber-Welded Mesoporous Cotton Composites.

Natural fiber-welded (NFW) biopolymer composites are rapidly garnering industrial and commercial attention in the textile sector, and a recent disclosure demonstrating the production of mesoporous NFW materials suggests a bright future as sorbents, filters, and nanoparticle scaffolds. A significant roadblock in the mass production of mesoporous NFW composites for research and development is their lengthy preparation time: 24 h of water rinses to remove the ionic liquid (IL) serving as a welding medium and then 72 h of solvent exchanges (polar to nonpolar), followed by oven drying to attain a mesoporous composite. In this work, the rinsing procedure is systematically truncated using the solution conductivity as a yardstick to monitor IL removal. The traditional water immersion rinses are replaced by a flow-through system (i.e., infinite dilution) using a peristaltic pump, reducing the required water rinse time for the maximum removal of IL to 30 min. This procedure also allows for easy in-line monitoring of solution conductivity and reclamation of an expensive welding solvent. Further, the organic solvent exchange is minimized to 10 min per solvent (from 24 h), resulting in a total combined rinse time of 1 h. This process acceleration reduces the overall solvent exposure time from 96 to 1 h, an almost 99% temporal improvement.

Can salivary lactate be used as an anaerobic biomarker?

Salivary lactate has been suggested as a non-invasive anaerobic biomarker in sports medicine for decades, yet has not been widely applied until now. This study aimed to explore possible issues related to its application and suggest directions for future method improvement. A liquid chromatography-mass spectrometry (LC-MS) method for the determination of salivary lactate was developed, validated and applied on saliva samples collected from a group of professional sprinters (n=20). The samples were collected via chewing a cotton ball for one minute and centrifuging it afterwards. The evaluation included variation with mouth rinse times, consistency at different sampling times, change after treadmill or cycle ergometer trainings, and association with blood lactate. Sample sizes were calculated prior to the study. One-way analysis of variance (ANOVA), intra-class correlation coefficients (ICC) and relative standard deviation (RSD) were used to evaluate data variances. Pearson correlation was applied to show correlation between salivary and blood lactate. Effect sizes and power were calculated following ANOVA and correlation analyses. The RSD of the LC-MS method was 19.70%. Salivary lactate concentration was affected by mouth rinse times before sampling (ANOVA p=0.025, η 2=0.40, 1-β=0.99, ICC = 0.23, mean RSD of four sampling = 55.30%), and stabilized after mouth rinsing for three times. The concentrations at resting state across three weeks were consistent at group level (ANOVA p=0.57, η 2=0.03, 1-β=0.20), but varied greatly individually (ICC = 0.22, mean RSD = 56.16%). Salivary lactate level significantly increased after treadmill and cycle ergometer trainings (ANOVA p=0.0002, η 2=0.46, 1-β=0.9999 and ANOVA p=0.0019, η 2=0.40, 1-β=0.9993, respectively), and displayed positive correlation with blood lactate concentration (r=0.61, p=0.0004, 1-β=0.9596). Significant difference between male and female participants was observed in none of the tests conducted in this study. Salivary lactate was found to be a potential anaerobic biomarker. However, reproducible methods for sample collection and analysis, as well as more knowledge on the secretion mechanism and pattern of salivary lactate are required to make it a practical anaerobic biomarker.

Relative Cleanability and Sanitization of Blueberry Mechanical Harvester Surfaces

Berry crops are increasingly being harvested mechanically to reduce labor costs, but there is a lack of research on best practices for cleaning and sanitizing of mechanical harvesters to maintain proper food hygiene. Laboratory experiments were conducted with surface coupons cut from materials commonly used on blueberry harvesters, including polyethylene, high-density polyethylene, aluminum, extruded polycarbonate, acetal plastic, and stainless steel. Surfaces differed in their hydrophobicity and surface roughness, ranging from 0.04 µm for polycarbonate to 1.57 µm for acetal plastic. The relative cleanability of the surface coupons was assessed by determining the removal of an applied mock soil (dried blueberry puree) in a rinsing-shaking assay with distilled water at room temperature. Results showed that the amount of soil removed increased over time according to a negative exponential function, from 29.6% at 30 s to 40.3% at 240 s rinse time. Compared with the time effect, the differences in soil removal among surfaces were relatively small. The addition of cleaning agents and detergents did not improve soil removal, and the only treatment that removed significantly more soil than the water control was heated (50 °C) distilled water. In sanitization assays, three representative microorganisms were allowed to attach to surface coupons, then exposed to three different sanitizers (0.25% bleach with 200 ppm free-chlorine sodium hypochlorite, 0.30% SaniDate 5.0, or 1.0% No-Rinse Food Contact Cleaner Sanitizer). There was no significant surface effect on microbial reductions following sanitizer treatment. For Bacillus amyloliquefaciens, none of the sanitizers significantly reduced population densities below the water control. In contrast, surface populations of Rhodoturula mucilaginosa and Epicoccum nigrum were reduced significantly by all three sanitizers, with SaniDate (23.0% hydrogen peroxide + 5.3% peroxyacetic acid) resulting in the greatest reduction.

SnapFib: An easy build Arduino based tabletop prototype for thin film deposition by Successive Ionic Layer Adsorption and Reaction method

Non-vacuum-based techniques are suitable for thin-film deposition with precision stoichiometric control. Among those, the Successive Ionic Layer Adsorption and Reaction (SILAR) method is gaining popularity for its aqueous-based almost room temperature deposition option. This method has many advantages, including the ability to control the elemental composition and stoichiometry of precursors. It is also suitable for large-area deposition. It has many runtime parameters, e.g., the number of cycles, dip time, rinse time, etc., that control the quantitative and qualitative physical properties of the deposited film. But manually controlling all these parameters for the whole process is very difficult and cumbersome. Although there are several reports published on this similar type of home-built prototype, for fast, accurate, and economically affordable deposition operations, we need to develop a machine that maintains all the properties of the SILAR process and can be made using cheap technologies. Here we report the SnapFib, a cost-effective automated tabletop prototype machine that is easy to build for thin-film deposition on soda-lime glass substrates by the SILAR method without almost any human intervention. SnapFib is built using linear actuators, an ATmega328P (a microcontroller available on Arduino boards), and some other parts collected from laboratory sites. The whole firmware needed for this device has been developed and maintained using the Arduino IDE (Integrated Development Environment). All required functional features and control parameters are encoded in the microcontroller firmware. The construction cost of this prototype is around 600 USD. We validated our construction through XRD (X-ray Diffraction) and FESEM (Field Emission Scanning Electron Microscope) characterizations of thin films that were deposited by SnapFib. Since this is built under the CC-BY license, students and researchers can freely perform and validate their experiments and modify the hardware and software as required. With how easy it is to make and how much it costs; we hope that many thin-film deposition labs will quickly start using SnapFib as an added benefit.

Optimization of an intra-oral solid-phase microextraction (SPME) combined with comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry (GC × GC-TOFMS) method for oral aroma compounds monitoring of Baijiu

The ‘‘after-odor” is essential to the quality and consumer preference of Baijiu. An intra-oral solid-phase microextraction (SPME) combined with comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry (GC × GC-TOFMS) was developed for oral aroma compounds monitoring of Baijiu. The extraction time, sip volume and rinse time were 120 s, 5 mL, and 10 s, respectively. The procedure showed good performances at concentrations of 1.56 μg/L–1500 mg/L for different aroma compounds of Baijiu (most R2 > 0.9). Furthermore, the optimized procedure detected 85 aroma compounds with different chemical structures and provided good representations of the light, strong, soy sauce and mix aroma type Baijiu’s oral aroma profiles. Principal component analysis’s (PCA) cumulative interpretation rate was 72.42%. The acceptable performance of this procedure can be combined with dynamic sensory evaluation to improve the quality of the Baijiu aroma.

RETRACTED ARTICLE: Direct quantification of iodine in nuclear wastes using DRC-ICP-MS

A method was developed for the direct quantification of iodine in Hanford tank waste using inductively coupled plasma mass spectrometry coupled with a dynamic reaction cell. The following parameters were optimized to lower the 129 m/z background signal and minimize iodine carryover effects: diluent, oxygen gas flow rate, radiofrequency voltage applied to the dynamic reaction cell, and rinse times. The concentration of 129I was 23 ± 1 µg/mL (n = 4, ± 1σ) in the Hanford waste tank 241-AP-107; to our knowledge this work constitutes the first report of iodine concentration in the tank waste.

Fuzzy Logic Based Control System for Intelligent Washing Machines

Nowadays, in Libyan households, washing machines are very common items. It is not only a big time saver over hand washing, but also it saves a great effort, people can carry out another task and then return back to the machine to get their clothes clean and even dry. The only things they need to do are load the clothes into the machine, throw detergent in, run it, and walk away. This paper shows the importance of fuzzy logic control based washing machine to get a suitable wash, rinse, and spin time for different types and amount of clothes and amount of dirtiness. The process is based on fuzzy inference system. The signals that come out from sensors are fed to the fuzzy controller as non-precise inputs to get the desired output (a crisp value of washing time, rinsing time and spinning time). The Simulation was done by MATLAB’s fuzzy logic toolbox.

Mouth Rinsing Cabohydrates Serially Does Not Improve Repeated Sprint Time.

Sensing carbohydrates via the oral cavity benefits performance outcomes during brief high intensity bouts of exercise. However, the extent to which carbohydrates need to be present in the oral cavity to influence sprint performance is less understood. The purpose of this study was to determine if serial increases in carbohydrate rinse time across sprint sets attenuates increases in sprint time compared to no serial increases in carbohydrate rinse time across sprint sets. Fifteen sprint trained participants completed three repeated anaerobic sprint tests (RAST), 3 sets of 6 x 35-m sprints, under two different carbohydrate mouth rinsing (CMR) conditions; (1) rinsing for only 5 seconds (s), and (2) rinsing for 5 s, 10 s and 15 s (serial rinse). Prior to a RAST, participants provided perceived recovery status (PRS) and perceived feeling of arousal (FAS). Upon completion of each individual sprint, participants gave a rating of perceived exertion (RPE). A lactate sample was taken upon completion of each individual sprint set and after all 3 RASTs a session rating of perceived exertion (S-RPE) was measured. There were no significant differences in peak (p = 0.18) and average sprint time (p = 0.41). There were no significant differences in perceptual measures: RPE, PRS, FAS, S-RPE or for blood lactate concentration between CMR conditions. Overall, serial rinsing resulted in changes that were most likely trivial, but showed a 50% chance in perceiving a sprint session as less difficult. Rinsing carbohydrates in a serial manner between repeated sprint sets produces trivial changes of sprint speed and perceptual measures from sprint performance.

Electrochemically building three-dimensional supramolecular polymer hydrogel for flexible solid-state micro-supercapacitors

Conducting polymer hydrogels (CPHs) advantageously synergize the features of both hydrogels and conducting polymers and have gained ground in various applications such as energy storage devices, catalysis and sensors. Conventional synthesis of CPHs usually couples with introducing of non-conductive polymer frameworks or chemical oxidative initiators, which will inevitably lead to degraded electrochemical performance and long rinse time. Here, we report an electrochemical polymerization method free of frameworks and initiators to build three-dimensional (3D) polyaniline/phytic acid supramolecular hydrogel. This CPH provides high conductivity of 0.43 S cm−1 and improved electrode interfaces between electronic transporting phase and ionic transporting phase. As a result, the CPHs exhibit large areal capacitance of 561.6 mF cm−2 and specific capacitance of 311.3 F g−1. Flexible solid-state micro-supercapacitors (MSCs) based on this CPHs deliver high areal capacitance of 135.9 mF cm−2 and considerable integratable potential via tandem and parallel connection. Cyclic stability is demonstrated by 10,000 galvanostatic charge/discharge cycles with 76% capacitance retention. Besides, electrochemical performance of this device can be maintained under different mechanical loadings such as bending and twisting, which makes it a promising power supply candidate for future wearable electronics and on-chip integrated circuit.

Characterization of surface layers formed on DU10Mo ingots after processing steps and high humidity exposure

The design of monolithic UMo fuel elements fabricated from low-enriched uranium for use in high-power research reactors requires bonding of the fuel foil to either Al cladding or a Zr barrier layer. Processing of the UMo ingot to final foil form has the potential to generate surface layers on the foil that differ from the bulk, metallic UMo. The interfacial properties between the UMo and Zr or Al cladding layers will then be determined by these surface layers. We use x-ray photoelectron spectroscopy, cross-sectional scanning electron microscopy, and atomic force microscopy to characterize the composition, oxidation state, and morphology of the surface layers that form after hot rolling and cold rolling depleted U–10 wt% Mo alloy (DU10Mo). A thick uranium nitride layer is observed after hot rolling, although its origin is likely from a previous processing step. The efficacy of acid etching in HNO3 is compared to that of electropolishing in H2SO4 to remove surface nitride and oxide layers, and both methods are found to be similarly effective. Both laboratory (low humidity) air exposure and longer rinse times in water are shown to promote the formation of surface oxide layers. Exposure of both acid-etched and electropolished DU10Mo foils to humid air (97% relative humidity) for six weeks results in formation of a thick oxide layer due to corrosion. The oxide layer on the acid-etched foil is thicker and more highly oxidized than the oxide layer that forms on the electropolished foil, and these differences in oxidation behavior are attributed to higher surface roughness on the acid-etched foil. In general, Mo is found to play a role as a sacrificial element, typically exhibiting a larger ratio of Mo6+/Mo4+ than U6+/U4+. This is unexpected, given the greater thermodynamic driving force to form U oxides than Mo oxides.

Megasonic Enhanced Photo Resist Removal Using Unique Solvent Free Phase-Fluids on an Advanced Single Wafer Resist Processing System

Removal of photoresist materials (resist stripping) is very straightforward in theory, but can be difficult and complicated in practice. Classical methods have included SPM (sulfuric peroxide module) /piranha, ozone and UV ozone, solvent based fluids and plasmas. All of the legacy methods include hazardous and toxic materials and/or high equipment expense as well as multi-step complexity. The stripping process becomes even more challenging by factors such as thick resist, cross-linked resist or sensitive metals or materials under the resist. This study was carried out In order to determine feasibility of the use of a unique phase-fluid based photoresist-stripper in commercial semiconductor resist removal process steps. Due to their highly dynamic inner structure, phase-fluids penetrate into the polymer network of photoresists and lift the material from the surface. As these water-based stripping fluids are non-aggressive, non-toxic, and require no special handling, the ability to apply them to industry standard resists will result in a reduction of toxic and dangerous chemistries and the environmental impact of their disposal. To investigate the impact of megasonic energy on the process time in both the active and rinse steps and therefore throughput, the study included the introduction of megasonics as a process variable in all test combinations. The study was broken down into two phases. Phase one consisted of a broad spectrum screening process incorporating nine standard photoresists Fig. 1 with various standard thermal treatments as well as a selection of five phase-fluid formulations. The tests were carried out in a single substrate stagnant immersion tank incorporating a megasonic transducer illustrated in Fig. 2. Process time was defined as the time from immersion of the substrate until the photoresist was completely removed. Process variables tested for each resist/phase-fluid combination included three process temperatures, ambient, 40c and 60c as well as the addition of megasonic energy at ambient with a frequency of 925KHz at a dosage of 1.5W/cm2 directly coupled. The results achieved in this phase one screening were used to select the best case phase-fluid, and process conditions for each of the screened photo resists. These conditions became the baseline parameters for phase two. Phase two of the study was carried out in actual single wafer production conditions on an EVG®100 Series Resist Processor equipped with a MegPie® large area megasonic transducer. Process recipes were established using phase one parameters and then refined for optimum total process time, including the actual phase-fluid process time and rinse time. Spin off and dry cycles were kept constant in all process recipes. Complete resist strip process times of <20 seconds were achieved with several photoresist phase fluid combinations while other combinations involving BCB based resist resulted in little to no removal. The results achieved in phase two testing demonstrate the feasibility of a phase-fluid based photo resist strip in a single wafer platform with megasonic enhancement for specific photo resists. Figure 1

Growth Inhibitory Effects of Adhatoda vasica and Its Potential at Reducing Listeria monocytogenes in Chicken Meat.

The inhibitory effects of Adhatoda vasica ethanolic leaf extract (AVELE) against Listeria monocytogenes were examined to assess its potential to preserve minimally processed meat products safely. The total phenolic, flavonoid, and alkaloid levels in AVELE were 10.09 ± 4.52 mg of gallic acid equivalents (GAE)/g, 22.43 ± 1.62 mg of quercetin equivalents/g, and 19.43 ± 3.90 mg/g, respectively. AVELE (1, 5, 10, or 20%) had considerable antibacterial effects against L. monocytogenes NCIM 24563 in terms of the inhibitory zones (7.4–13.6 mm), MIC (100 mg/mL or 10% formulated solution), reduced cell viability, potassium ion efflux, and the release of 260-nm absorbing materials and extracellular ATP. AVELE was used as a rinse solution (5, 10, and 20%) for raw chicken breast meat. A 20% rinsing solution applied for 60 min inhibited the L. monocytogenes NCIM 24563 counts significantly on raw chicken breast meat. Moreover, L. monocytogenes NCIM 24563 did not grow in the meat sample when the rinse time was increased to 90 min at the same concentration. L. monocytogenes showed a greater reduction to ~3 CFU/g after rinsing with a 10 and 20% AVELE solution for 30 min than with a 5% AVELE solution. The rinsing processes with AVELE produced the final cooked chicken products with higher sensory attribute scores, such as taste, juiciness, and tenderness, compared to the control group along with a decrease in microbial contamination. Chicken meat rinsed with AVELE (rinsing time of 90 min) showed better sensory attribute scores of juiciness and tenderness, as well as the overall sensory quality compared to the untreated group. This research highlights the effectiveness of AVELE against L. monocytogenes NCIM 24563, suggesting that AVELE can be used as an effective antimicrobial marinade and/or a rinse for meat preservation.

Rinsing of High-Aspect-Ratio Features on Patterned Wafers

A comprehensive process model is developed to simulate the mechanism and the dynamics of rinsing and cleaning of deep and narrow structures on patterned substrates. This process is critical in a number of applications such as post-etch cleaning of patterned wafers during the manufacturing of semiconductor devices. The model takes into account various mass transport mechanisms including convection and diffusion/dispersion that occur simultaneously with various surface interactions such as adsorption and desorption of impurities on the substrate surfaces. The influences of charged species in the bulk and on the surface, and their induced electric field that affect both transport and surface interactions, are included in this paper. The results of this paper illustrate the model usefulness and potentials to predict the change in the rinse time and efficiency with changes in the key operational parameters such as temperature, concentration, flow rate, and mass transfer on the wafer surface. Ammonium hydroxide on SiO 2 surface is used as the model system in this study because of its wide application; however, the model can be used for analyzing the rinsing of other impurities by simply changing the model parameter inputs.

Impact of soap type—foaming vs. gel-based—on handwashing time

Handwashing (HW) is used daily in the food service industries to prevent disease transmission. Limited published research into the efficacy of foaming handsoap exists when compared to gel-based handsoap. Understanding how foaming soap may affect HW behavior as represented by time is critical to maximize HW effectiveness and minimize transmission of foodborne pathogens. Here, 12 participants completed a baseline HW, and then applied a known amount of Glo Germ (GG) fluorescent lotion and washed their hands with the assigned handsoap. Hands were then swabbed to quantify the amount of GG remaining on hands. Hand wash and hand rinse times were also recorded. No significant difference in efficacy between soap types was observed 1) in terms of GG remaining (p = 0.35) nor 2) in hand wash and rinse times (p = 0.77 and p = 0.48, respectively). However, consistently longer time (4.5 s on average) in both wash time and rinse time for gel-based handsoap did occur when compared to foaming handsoap. This may indicate a possible benefit to using gel-based handsoap as opposed to foaming types for better protection of public health; however, more research is needed to elucidate these differences.

Impacts of main parameters on the regeneration process efficiency of several ion exchange resins after final purification of olive mill effluent

Abstract The key for the cost-efficient application of ion exchange (IE) processes relies on the fact that resins should be effectively regenerated to ensure their operation for the maximum possible working cycles. The main objective of this research work was to examine the effect of the main parameters affecting the regeneration process of several IE resins previously used for the purification of secondary-treated olive mill wastewater (OMW-2ST), comprising regenerant concentration and type, operating temperature and flow rate. For this purpose, the impacts on the regeneration and rinse times as well as the regeneration efficiency were addressed. Results show regeneration time decreased but rinse time increased with regenerant concentration increment for all resins. As a general rule, minor flow rate (2.5 L h −1 ) provided the highest possible regeneration, whereas efficiencies above 96% were noted upon the lowest temperature examined (298 K), which have both important implications on the cost-efficiency of the regeneration and integral effluent treatment process. Finally, 0.6 L HCl 4% and 0.8 L H 2 SO 4 2% solutions achieved complete regeneration of Dowex Marathon C and Dowex MAC 3 resins, whereas 0.7 L and 1 L NaOH 4% ensured complete regeneration of Amberlyst A26 and Amberlite IRA-67 resins, respectively.

Intestinal microbiota of ornamental fish Carassius auratus

Intestinal microbiota is an essential component for any organism life, because it directly affects nutrient assimilation, growth and health processes. However, in many animals and in case of fish is unknown how Intestinal microbiota is formed, which species are dominant and which one has capacity probiotic for use in aquaculture. The goal of this study was to establish the bacterial load that dominates the back intestine of Carassius auratus. A batch of 200 healthyjuvenilefishes were obtained from an ornamental fish farm in Mexico City. The fish were maintained in two culture beakers of 100 L during 15 day to acclimatization to ensure any sign of injury disease. To extract the back of gastrointestinal tract, which was rinse several times with distilled water for food and feces residues elimination. The sample was inoculated in 9 mL of sterile saline solution and from this, three dilutions in a 1:10 relation were made, inoculating 0.1 mL from each dilution in agar plates MRS, BHI and TCBS, and were incubated at 27oC for 24 hours. Subsequently a colony forming units (CFU mL-1) count was made, with the help of a Quebec counter type. Colonies were purified through successive inoculations. The molecular identification was made out by sequencing the gene RNAr 16S using Wizard Genomic. Molecular identification showed that the back region of the intestinal tract of C. auratus was dominated by phylum Proteobacteria and Firmicutes represented by the genus Bacillus , Vibrio , Vagococcus , Brevibacillus , Aeromonas , Pseudomonas , Shewanella , Enterococcus , Paenibacillus and Morganella. In relation to bacterial abundance by specie it was established that Bacillus sp. and Pseudomonas stutzeri were the most abundant reaching CFU mL -1 counts of 210 and 167 respectively, followed by Paenibacillus lactis with 103 CFU mL -1 and Bacillus cereus with 100 CFU mL -1 while Enterococcus eurekensis was the least abundant with an average value of 6 CFU mL -1 .

A Comparison of Different Corneal Iontophoresis Protocols for Promoting Transepithelial Riboflavin Penetration.

To measure corneal riboflavin penetration using different transepithelial iontophoresis protocols. Freshly enucleated rabbit eyes were divided into nine treatment groups of 4 eyes. One group, in which 0.1% wt/vol riboflavin was applied for 30 minutes without iontophoresis after corneal epithelial debridement, acted as a control. The remaining groups were treated with an intact epithelium using different riboflavin formulations and varying iontophoresis current, soak, and rinse times. After riboflavin application, eyes were snap frozen in liquid nitrogen. Corneal cross sections 35 μm thick were then imaged immediately by two-photon fluorescence microscopy, using image processing software to quantify stromal riboflavin concentration at different corneal depths. In the epithelium-on iontophoresis treatment groups, greater stromal riboflavin penetration was achieved with higher-concentration riboflavin solutions, greater iontophoresis dosage, and longer solution contact times. A protocol utilizing 0.25% wt/vol riboflavin with benzalkonium chloride (BAC) 0.01% and two cycles of applied current and subsequent soaking (1 mA 5 minutes, soak 5 minutes; 0.5 mA 5 minutes, soak 5 minutes) achieved similar stromal riboflavin penetration to epithelium-off controls. The best-performing non-BAC-containing protocol produced stromal riboflavin penetration approximately 60% that of epithelium-off controls. Riboflavin solutions containing saline resulted in minimal stromal penetration. Riboflavin loading within the epithelium was equivalent to or higher than that in the subjacent stroma, despite rinsing the ocular surface with balanced salt solution. Modified iontophoresis protocols can significantly improve transepithelial riboflavin penetration in experimental corneal collagen cross-linking.

Mathematical modeling and cycle time reduction of deposit removal from stainless steel pipeline during cleaning-in-place of milking system with electrolyzed oxidizing water

The safety of raw milk largely depends on using a clean milking system during the milk production. The milking system cleaning process widely used on dairy farms is a highly automated process called cleaning-in-place (CIP), which comprises of four cycles: i) warm water rinse; ii) alkaline wash; iii) acid wash; and iv) sanitizing rinse before the next milking event. Electrolyzed oxidizing (EO) water is an emerging technology, which consists of acidic and alkaline solutions by the electrodialysis of dilute sodium chloride solution. Previous studies in our lab showed that EO water can be an alternative for milking system CIP. Despite the progress made to enhance the CIP performance and evaluate alternative CIPs, the mechanisms behind the cleaning processes were still largely unclear. Therefore, this study was undertaken to evaluate the deposit removal rate during the EO water CIP process using a stainless steel surface evaluation simulator. Deposit removal data from the simulator formed the basis for developing mathematical models to describe the deposit removal process during the CIP process with EO water. Stainless steel straight pipe specimens were placed at the end of undisturbed entrance length along the simulator pipeline. The mass of milk deposits on the inner surfaces of the specimens were measured using a high precision balance after the initial soiling, and then after certain time durations within the warm water rinse, alkaline wash, and acid wash cycles. A unified first order deposit removal rate model dependent on nth power of remaining deposit mass was used for all three cycles. ATP bioluminescence method was also used as a validation approach at the end of each CIP cycle. Experimental results showed that the milk deposit on the inner surfaces of the specimens was removed rapidly by the warm water rinse within 10 s of rinse time. For the alkaline and acid wash cycles, the co-existence of a fast deposit removal at the beginning of the wash cycle and a slow deposit removal throughout the entire wash cycle was inferred. The proposed models matched the experimental data with small root mean square errors (0.23 mg/[(mg) (m2)] and 0.07 mg/[(mg) (m2)] for the upstream and downstream locations, respectively) and satisfactory percent error differences (3.67% and 0.93% for the upstream and downstream locations, respectively). Based on the experimental data and the proposed models, the time duration of the CIP process was shortened by 55% (10 s warm water rinse, 3 min alkaline wash and 6 min acid wash) and validated, which yielded an average deposit of 0.28 mg/[(mg) (m2)] at the end of the CIP as compared with that of 0.29 mg/[(mg) (m2)] at the end of the original CIP, to achieve a satisfactory CIP performance for the simulator.