Body weight-based iodinated contrast immersion timing for human fetal postmortem microfocus computed tomography.

Objectives: The aim of this study was to evaluate the length of time required to achieve full iodination using potassium tri-iodide as a contrast agent, prior to human fetal postmortem microfocus computed tomography (micro-CT) imaging. Methods: Prospective assessment of optimal contrast iodination was conducted across 157 human fetuses (postmortem weight range 2-298 g; gestational age range 12-37 weeks), following micro-CT imaging. Simple linear regression was conducted to analyse which fetal demographic factors could produce the most accurate estimate for optimal iodination time. Results: Postmortem body weight (r2 = 0.6435) was better correlated with iodination time than gestational age (r2 = 0.1384), producing a line of best fit, y = [0.0304 × body weight (g)] - 2.2103. This can be simplified for clinical use whereby immersion time (days) = [0.03 × body weight (g)] - 2.2. Using this formula, for example, a 100-g fetus would take 5.2 days to reach optimal contrast enhancement. Conclusions: The simplified equation can now be used to provide estimation times for fetal contrast preparation time prior to micro-CT imaging and can be used to manage service throughput and parental expectation for return of their fetus. Advances in knowledge: A simple equation from empirical data can now be used to estimate preparation time for human fetal postmortem micro-CT imaging.

Impact of chemical modification by immersion with malic acid on the physicochemical properties and resistant starch formation in rice.

The effects of immersion time on the physicochemical properties and resistant starch (RS) formation of malic acid-treated rice were investigated. Malic acid treatment decreased the frequency of cracks within the rice kernel. The color (lightness) was significantly affected by the immersion time, reflecting the browning of rice. The degree of substitution gradually increased with the immersion time and reached a plateau after 12 h, and the intensity of the C=O bond peak detected in the Fourier-transform infrared spectroscopy showed a similar trend. However, the crystallinity of rice decreased as the immersion time increased, which was confirmed by the X-ray diffraction and thermal transition properties. A gradual increase in RS was observed as the immersion time and DS increased, ranging from 44.5% to 73.3%, reaching a maximum after 12 h of immersion. Therefore, 12 h was determined to be the optimal immersion time for maximizing RS content. This information about the structural characteristics and heat-stable properties of malic acid-treated rice in starch digestion can be used to develop a low-digestible food ingredient and lead to further application of the study. PRACTICAL APPLICATION: This study reported the preparation and physicochemical properties of malic acid-treated resistant starch with different immersion times. This information could contribute to the structural characterization of resistant starch and the development of low-calorie processed rice products.

Mitigation effects of phlorizin immersion on acrylamide formation in fried potato strips.

BACKGROUND: Several researches reported that natural polyphenols affected acrylamide formation of fried products. However, the effects of different variety of polyphenols on acrylamide formation were distinct. In this study, we isolated and purified phlorizin from apples and identified the influence of phlorizin immersion on acrylamide formation and sensory properties of fried potato strips with regard to the immersion concentration, time and temperature. RESULTS: The acrylamide formation of fried samples decreased as the phlorizin concentration increased from 0 to 0.3 g kg-1 , and 0.14 g kg-1 could be selected as the suitable immersion concentration to dramatically inhibit acrylamide formation with considering the cost of industrial production. Additionally, the acrylamide formation significantly reduced from 8.71 × 10-3 to 2.13 × 10-3 g kg-1 lyophilized weight (LW) with immersion time from 0 to 120 min, and 60 min could be selected to significantly reduce acrylamide formation in consideration of efficiency of the large-scale industrial processing. However, the effect of phlorizin immersion temperature on acrylamide formation of fried samples was not significant. Compared to the fried samples without immersion, the phlorizin immersion improved the color properties and the change of texture parameters was slight. CONCLUSION: The fresh potato strips immersed in the phlorizin solution of 0.14 g kg-1 at 40 °C for 60 min before frying could significantly decrease acrylamide formation of fried samples and retain the majority of fresh sensorial properties. The significant correlations obtained between sensory properties and acrylamide content indicated the sensory properties could be used as the indicator of acrylamide levels during industrial processing. © 2020 Society of Chemical Industry.

The empirical prediction of weight change and corrosion rate of low-carbon steel.

Understanding the corrosion rate of metallic building materials is very important to maximize their beneficial use of public facilities. Direct measurements of the weight change and corrosion rate would be time consuming and expensive. This study aims to develop new empirical models based on the experimental data of testing 25 specimens immersed in five different environments for predicting the weight change and corrosion rate of the low-carbon steel. Using the equation developed based on the correlation between corrosion rate and chloride ion concentration is able to predict the corrosion rate of low-carbon steel at the limited chloride ion concentration. An increase in the trend lines of plotting the modeled and measured weight change of low-carbon steel versus immersion time is very similar to each other and progressively increase with increasing of the NaCl concentration. The corrosion rate of low-carbon steel increases from 0.202 to 0.286 mm/y with increasing of the NaCl concentration from 0 to 5% (w/w) in aqueous solution. The weight change and corrosion rate of the steel material are predicted using the new empirical models to contribute to the most reliable applications of low-carbon steel building materials in the future.

Trehalose uptake and dehydration effects on the cryoprotection of CHO-K1 cells expressing TRET1.

Chinese hamster ovary cells (CHO-K1 cells) in which the trehalose transporter (TRET1) is expressed can have greater cryoprotection than ordinary CHO-K1 cells. This study examines the uptake characteristics of trehalose into cells via TRET1 and determines the influence of intracellular trehalose on the freeze-thaw viabilities. In our experiments, the intracellular trehalose concentration is controlled by the extracellular trehalose concentration and the immersion time in a freezing solution. In this freezing solution, both kinds of CHO-K1 cells are independently dispersed with various amount of trehalose, and then put into the CO2 incubator for 0-6 h. After a set immersion time, the cell-suspended sample is cooled to 193 K, stored for 1 week, then quickly thawed at 310 K and its viability measured. The uptake amount of intracellular trehalose is measured before freezing. We find an upper limit for the uptake amount of trehalose when the extracellular trehalose concentration is about 400 mM, at which the freeze-thaw viability is the highest. When the extracellular trehalose concentration exceeds 400 mM, shorter immersion times are needed to obtain the maximum freeze-thaw viability. Also, longer immersion weakens the cells. Our analyses indicate that when the extracellular trehalose-concentration is less than 400 mM, the trehalose uptake occurs more slowly with less dehydration, resulting in less stress on the cell. When the extracellular trehalose concentration exceeds the saturation level, the cell is stressed by the excess dehydration due to the remaining osmotic pressure, with apoptosis occurring before freezing.

Side-Group-Induced Polymorphism in Self-Assembled Monolayers: 3,5-Bis(trifluoromethyl)benzenethiolate Films on Au(111).

The structure and molecular organization of self-assembled monolayers (SAMs) depend on a complex interplay of intermolecular and molecule-substrate interactions, so that even a small change in molecular composition can result in noticeable changes in the SAM structure. Herein we show that decoration of the most basic aromatic SAM constituent, benzenethiol, with two trifluoromethyl groups leads to distinct polymorphism in the respective SAMs, in which the appearance of a specific structural phase or a combination of several different phases is dependent on the parameters of the preparation procedure. High-quality films with a single crystallographic phase and significantly large domains could only be prepared after a short immersion time (5 min) and an additional re-immersion of the sample in pure ethanol at an elevated temperature. A standard 24 h immersion at room temperature led to poorly defined films with a large defect density and only a small portion of the surface covered by well-ordered molecular domains.

Multiplicación en sistema de inmersión temporal del clon de Malanga Viequera -Xanthosoma spp / Multiplication in temporary immersion system cocoyam clone Viequera - Xanthosoma spp

El Sistema de inmersión temporal (SIT) constituye una alternativa en la micropropagación de plantas. El presente trabajo se realizó con el objetivo de establecer un protocolo para la multiplicación en SIT del clon de malanga “Viequera”. Se evaluó el efecto de tres tiempos de inmersión (7, 14 y 21 minutos), tres frecuencias de inmersión (2, 4 y 6 horas por día), cuatro volúmenes de medio de cultivo (5, 10, 15 y 20 ml por brote inicial) y cuatro tiempos de cultivo (15, 18, 21 y 25 días) en la multiplicación de los brotes de yemas axilares. Con tiempo de inmersión de 14 minutos cada 4 horas, un volumen de 15 ml de medio de cultivo por brote inicial y 18 días de cultivo, se logró el mejor comportamiento en la multiplicación de los brotes de yemas axilares, con un coeficiente de multiplicación de 10,50. El protocolo propuesto aumenta la productividad del material propagado en comparación con los desarrollados en medios de cultivo semisólidos, lo que representa una reducción en los costos de producción al introducir la multiplicación del cultivo en laboratorios comerciales de propagación.

Temporary Immersion System (TIS) is a alternative in the micropropagation of plants. This work was carried out to establish a protocol for the multiplication of clone TIS cocoyam “Viequera”. The effect of three immersion times (7, 14 and 21 minutes), three immersion frequencies (2, 4 and 6 hours per day), four volumes of culture medium (5, 10, 15 and 20 mL per shoot initial) and four times of cultivation (15, 18, 21 and 25 days) in the multiplication of shoots from axillary buds. With immersion time of 14 minutes every 4 hours, a volume of 15 ml of culture medium for initial outbreak and 18 days of culture, achieved the best performance in the multiplication of shoots from axillary buds, with a coefficient of multiplication 10.50. The proposed protocol increases the productivity of propagated material compared to those developed in semisolid culture media, representing a reduction in production costs by introducing the increase in cultivation in commercial laboratories.

Multiplicación en sistemas de inmersión temporal y enraizamiento ex vitro de ocumo blanco (Xanthosoma sagittifolium (L) Schott) / Multiplication in temporary immersion systems and ex vitro rooting of white cocoyam (Xanthosoma sagittifolium (L) Schott)

El ocumo (Xanthosoma sagittifollium (L.) Schott) es una Arácea cultivada en países tropicales debido al valor nutritivo de sus cormos. La principal limitante para su cultivo es la carencia de semilla de calidad, por esta razón se planteó evaluar la multiplicación de brotes de ocumo blanco en sistemas de inmersión temporal, y el enraizamiento ex vitro de los mismos, para lo cual se estudió el tiempo y la frecuencia de inmersión, y la densidad de explantes sobre la proliferación de los brotes. Asimismo, el efecto del ácido indolacético (AIA) y ácido indolbutírico (AIB) sobre el enraizamiento ex vitro de brotes. De acuerdo con los resultados obtenidos, la mayor eficiencia en la proliferación de brotes se obtuvo utilizando el sistema de inmersión temporal del tipo RITA®, con una frecuencia y tiempo de inmersión de 6 veces/día y 5 min, respectivamente, y una densidad de 9 explantes/RITA®. En el enraizamiento ex vitro se determinó que bajo las condiciones de cultivo empleadas no es necesario el uso de auxinas. Se concluye que es posible la multiplicación eficiente de ocumo blanco en sistemas de inmersión temporal, y realizar el enraizamiento ex vitro sin el uso de auxinas.

The white cocoyam (Xanthosoma sagittifollium (L.) Schott), is an Arácea cultivated in tropical countries, due to the nutritional value of its corms. The main limiting factor for cultivation is the lack of healthy seed, by this reason be outlined to evaluate the multiplication of shoots of white cocoyam in temporary immersion systems and the ex vitro rooting of the same. For that which, itself study, the time and frequency of immersion and the density of explants on the proliferation of the shoots. As well as, the effect of the indole acetic acid (IAA) and indole butyric acid (IBA) on ex vitro rooting the shoots was studied. According to the results obtained, the greater efficiency in the proliferation of shoots was obtained utilizing the temporary immersion system of the type RITA®, with a frequency and time of immersion of 6 times/day and 5 min, respectively and a density of 9 explantes/RITA®. In the ex vitro rooting was determined that under the conditions of employed cultivation is not necessary the use of auxins. It is concluded that is possible the efficient multiplication of white cocoyam in temporary immersion systems and to carry out the ex vitro rooting without the use of auxins.

Adsorption behavior of γ-aminopropyl trimethoxysilane on copper foil.

The adsorption behavior of γ-aminopropyl trimethoxysilane (γ-APS) on copper foil is investigated by using X-ray photoelectron spectroscopy (XPS). Copper foil is immersed in a diluted aqueous solution of γ-APS and dried in air. It is found that γ-APS is adsorbed onto the surface almost without hydrolysis. Further, the depth profile by XPS analysis shows that γ-APS is not hydrolyzed even in the inside layer. In order to obtain hydrolyzed γ-APS on the copper foil surface, the foil is freeze-dried as immersed in a diluted aqueous solution of γ-APS. A hydrolyzed form of γ-APS is found on the top surface. Further, the presence of a powder is confirmed in the bottom of the flask at the end of the freeze-dry experiment. XPS analysis shows the powder is a linear polymer and produced from the silane coupling agent.

Changes of the surface roughness depending on immersion time and powder/liquid ratio of various tissue conditioners / 대한치과보철학회지

STATEMENT OF PROBLEM: Volume stability, microstructure reproducibility and fluidity along with compatibility with dental stone must be in consideration in order to use tissue conditioner as a material for functional impression. There are few studies concerning the influence of time factor in oral condition on surface roughness of the stone and optimal retention period in the oral cavity considering such changes in surface roughness. PURPOSE: The purpose of this study was to find out the influence of various kinds of tissue conditioner, its powder/liquid ratio and immersion time on surface roughness of the stone. MATERIAL AND METHODS: Materials used in this study were the three kinds of tissue conditioners (Coe-Comfort, Visco-Gel, Soft-Liner) and were grouped into three: group R - mixed with standard powder/liquid ratio that was recommended by the manufacturers, group M - mixed with 20% more powder, group L - mixed with 20% less powder. Specimens were made with the size of 20 mm diameter and 2 mm width. Each tissue conditioner specimens were subdivided into 5 groups according to the immersion time (0 hour, 1 day, 3 days, 5 days, 7 days), completely immersed into artificial saliva and were stored under 37degrees C. Specimens of which the given immersion time elapsed were taken out and were poured with improved stone, making the stone specimens. Surface roughness of the stone specimens was measured by a profilometer. RESULTS: Within the limitation of this study, the following results were drawn. 1. Major influencing factor on surface roughness of the stone model made from tissue conditioner was the retention period (contribution ratio (rho) = 62.86%, P < .05) of the tissue conditioner in oral cavity to make functional impression. 2. In case of Coe-Comfort, higher mean surface roughness value of the stone model with statistical significance was observed compared to that of Soft-Liner and Visco-Gel as immersion time changes (P < .05). 3. In case of group L (less), higher mean surface roughness value of the stone model with statistical significance was observed compared to that of R (recommended) and M (more) group as immersion time changes (P < .05). CONCLUSION: We may conclude that as the retention period of time in oral cavity influences surface roughness of the stone model the most and as the kind of tissue conditioner and its P/L ratio may influence also, clinician should well understand the optimal retention period in oral cavity and choose the right tissue conditioner for the functional impression, thus making the functional impression with tissue conditioner usefully.