Nitrogen Vapor Research Articles

Comparison of vapor cooling characteristics of a triply periodic minimal surface and other channel geometries

Vapor cooling shield is a key technology for long-term cryogenic propellant storage in space. Cooling channels with a triply periodic minimal surface embedded inside are expected to improve its cooling performance. Herein, a cooling channel with a triangle cross-section embedded gyroid structure, a type of the triply periodic minimal surface structure, was additively manufactured. The pressure drop and heat transfer performances of the channel were experimentally measured using liquid nitrogen vapor. Furthermore, in addition to the gyroid-embedded channel, three channels with different cross-sections were fabricated for comparison: circular, triangle, and triangle with a step/groove on the bottom. The gyroid-embedded channel exhibited unique characteristics, with a thermal conductance that was approximately 40% higher than that of the channel with a simple triangle cross-section, but an excessive pressure drop of approximately 50 times higher than that of the other cross-sections. This denotes that strong vortex and turbulence and the flow separation cause excess pressure drop in the gyroidembedded channel. The pressure drop characteristic of the gyroid-embedded channel against the Reynolds number completely differed from that of the other channels, and the pressure drop of the gyroid-embedded channel can be estimated assuming analogy with particle packed beds.

Dimethyl acetamide and dimethyl sulfoxide associated at glucose and egg yolk for cryopreservation of Pseudoplatystoma corruscans semen

Abstract This study aimed to develop a protocol for the cryopreservation of Pseudoplatystoma corruscans semen. For this, mature males were hormonally induced with a single dose of carp pituitary extract (5 mg/kg body weight). Semen was collected and evaluated. Two cryoprotectants were tested to compose the diluents: dimethyl acetamide (DMA) and dimethyl sulfoxide (Me2SO), in two concentrations (8% and 10%), + 5.0% glucose + 10% egg yolk. The semen was diluted in a 1: 4 ratio (semen: extender), packed in 0.5 mL straws and frozen in a dry shipper container in liquid nitrogen vapors. After thawing, sperm kinetics, sperm morphology and DNA integrity of cryopreserved sperm were evaluated. Pseudoplatystoma corruscans males produced semen with sperm motility > 80%. After thawing, all treatments provided semen with total sperm motility > 40%, with no significant difference (P < 0.05) between them, as well as between the other sperm kinetic parameters evaluated. The treatments with DMA provided a smaller fragmentation of the DNA of the gametes. Sperm malformations were identified in both fresh and cryopreserved semen, with a slight increase in these malformations being identified in sperm from thawed P. corruscans semen samples.

Sperm cryopreservation in Windsnyer boars; principles, technique, and updated outcomes.

The domestic pig breeds are in danger of extinction whereas the erosion of their gene pool is a serious concern because they significantly contribute to the rich biodiversity. Overall aim of this study was to determine the protocol for preserving the semen of the Windsnyer boars for conservation. A total of 18 ejaculates (6 replications/boar) were collected from three Windsnyer boars of proven fertility with the use of hand-gloved approach method, twice per week. Boars semen were pooled and extended with Beltsville Thawing Solution [(BTS) IMV Technologies, France], held at 18°C for 3 hours and centrifuged. The sperm pellet was re-suspended with Fraction A (20% egg yolk + BTS) and cooled at 5°C for 1 hour. Following cooling, semen was divided and diluted into different cryoprotectants (ethylene glycol, glycerol, propanediol, ethylene glycol + glycerol + propanediol) at equal contribution to make the total concentrations [4, 8, 12 and 16% and the 0% (control; without cryoprotectant)] and loaded into 0.25 mL straws. Two cryopreservation methods (liquid nitrogen vapour and controlled rated) were used to cryopreserve the semen straws. Semen straws were thawed at different temperatures (5, 18, 37 and 40°C) and evaluated for sperm motility, viability, and morphology traits. Post-thawed sperm total motility (36.0±5.3) and live normal sperm (49.5±8.3) percentages were recorded to be higher in the treatment supplemented with 16% glycerol (P<0.05). The highest sperm total motility percentage was recorded at 40°C (26.8±3.2) thawing temperature for liquid nitrogen vapour treatment (P<0.05). In conclusion, 16% glycerol was found to be the suitable cryoprotectant concentration for semen cryopreserved with liquid nitrogen vapour method and thawed at 40°C.

Effect of sperm and glycerol concentration on epididymal sperm motility parameters after thawing

The aim of this study was to evaluate the effect of different glycerol concentrations and different sperm concentrations on stallion epididymal sperm motility indicators after thawing. For statistical analysis, 25 stallions were used. Collection of the epidydimal spermatozoa was performed as a retrograde flush of cauda epididymis and ductus deferens within 12 h post castration. After evaluation, the resuspended spermatozoa were centrifuged, the supernatant removed and the spermatozoa resuspended in Gent semen extender to get three different groups with different concentrations of sperm (250 × 106 in ml, 500 × 106 in ml, 1000 × 106 in ml) and different final glycerol concentrations (2%, 4%, and 6%). Therefore, 9 different samples were finally obtained from each stallion. The spermatozoa were packed and placed in a fridge (4 °C) for 2 h, then placed in liquid nitrogen vapour (−80 to −100 °C) and after 25 min plunged into the liquid nitrogen and stored at −196 °C for at least 5 days. The selected straws were individually thawed in a 38 °C water bath for 30 s prior to post-freezing analysis. Motility indicators were assessed at 0, 60, 120, and 180 min after thawing. Parametric test was used for analysis; the measured indicators were total motility, progressive motility, curvilinear velocity, straightness, and average-path velocity. In this study, the best results were reached in samples diluted into a concentration of 1,000 × 106 in ml, regardless of the concentrations of glycerol.

Streamlined Methods for Processing and Cryopreservation of Cell Therapy Products Using Automated Systems.

Streamlined procedures for processing and cryopreservation of cell therapies using good laboratory practices are integral to biomanufacturing process development and clinical applications. The protocol herein begins with the preparation of human cell types cultured as adherent (i.e., mesenchymal stromal cells, MSCs) or suspension cells (i.e., peripheral blood mononuclear cells, PBMCs) to comprehensively demonstrate procedures that are applicable to commonly used primary cell cultures. Cell processing steps consist of preparing high yields of cells for cryopreservation using instruments routinely used in cell manufacturing, including the Finia® Fill and Finish System and a controlled-rate freezer. The final steps comprise the storage of cells at subzero temperatures in liquid nitrogen vapor phase followed by the analysis of cell phenotypes before and after processing and cryopreservation, along with cell quality metrics for validation. Additionally, the protocol includes important considerations for the implementation of quality control measures for equipment operation and cell handling, as well as Good Laboratory Practices for cell manufacturing, which are essential for the translational use of cell therapies. Key features • The protocol applies to small- or large-scale manufacturing of cell therapy products. • It includes streamlined procedures for processing and cryopreservation of cells cultured as adherent cells (MSCs) and suspension cells (PBMCs). • Provides temperature control and rapid partitioning of sample in cryopreservation solution to maintain high viability of a range of cell types throughout the procedures. • This protocol employs the Finia® Fill and Finish System and a controlled-rate freezer. Graphical overview.

Post-Cryogenic Viability of Peach (Persica vulgaris Mill.) Dormant Buds from the VIR Genetic Collection

The long-term storage of the genetic resources of fruit crops for breeding needs can be freely developed by cryopreservation cuttings with dormant buds in liquid nitrogen vapor, but so far, this method has not been practically used for peach. Cuttings with dormant buds of five peach varieties growing in the field gene bank at Krymsk Experiment and Breeding Station of VIR were collected for cryopreservation in 2019–2021. The three-factor analysis of variance showed that the viability of peach cuttings was significantly affected by the year (p &lt; 0.001) and variety (p &lt; 0.001). According to the three-year average characteristics of the cultivars, the analysis of variance showed a significant difference in the viability of the cultivars after cryopreservation (p = 0.004). According to the results of the three years of study, cvs. ‘Podarok Kryma’ (43.3%) and ‘Lucky 24 B’ (44.4%) showed the lowest viability after cryopreservation, significantly lower than cvs. ‘Baby Gold’ (54.4%) and ‘Ustojchivy 90′ (55.6%). Cv. ‘Lyubimets Krasnodara’ (48.9%) occupied an intermediate position. These viability values exceeded the minimum requirement for samples subjected to long-term cryogenic storage in a cryobank. Low-temperature storage of peach cuttings at –5 °C can be used for short-term preservation. After low-temperature storage, the viability of peach cutting amounted to an average of 67.1%.

PEMANFAATAN EKSTRAK KULIT PISANG KEPOK (Musa paradisiaca L) SEBAGAI BAHAN PENGAWET TELUR AYAM PETELUR

Eggs easily experience a decrease in quality caused by physical damage, as well as evaporation of water, carbon dioxide, ammonia, nitrogen, and hydrogen sulfide from inside the egg. This study aims to find out the effect of giving banana peel extract (Musa paradisiaca L). effect on egg shrinkage, egg pH, and percentage of rotten eggs. The data was analyzed using RAL with treatment 4 and repeat 5. In the extract of banana peel by spraying several doses each experiment (4, 8.5, 12, 16) gr / 100 ml. The results of the study for the best value of each variable from 0-14 days are only treated at (P2) with a value (1,57 ± 0,29 ), this indicates that the extract dose of 8.5 gr / 100 ml is better. In this study it can be concluded that egg preservation with the utilization of banana peel extract with the addition of different extracts and storage for 14 days has not been able to inhibit the quality of eggs shown by the value of egg weight shrinkage, egg pH, and percentage of rotten eggs. It can be used as a reference base for future research, and further research is needed on the use of banana peel extract as a utilization of banana skin extract as a preservative of laying breed chickens

Experimental investigation on the effect of vapor environment on the pattern evolutions during sessile water droplet evaporation at low pressures

A series of experiments for water droplet evaporation into ethanol and nitrogen vapors at low pressures are carried out to investigate the influence of vapor environment on the evolution of thermal patterns induced by water droplet evaporation. Results show that when the water droplet evaporates in the ethanol vapor, the initial evaporation induces the surface fluid flows from the triple-line to the droplet apex. When the thermal flow loses stabilities, the surface temperature oscillations are shown as types of thermal waves. The transition of thermal patterns from gear-like temperature distribution, shifting multi-cells to the Bénard-Marangoni cell is captured and the wave number increases firstly, and then remains during the pattern evolutions. Reducing the initial pressure leads to an enhancement of the thermocapillary instabilities, which brings the critical time for the pattern transition forward. In the case of nitrogen environment, the transition of thermal patterns from central warmer region to the shifting multi-cells is recorded. The surface temperature in nitrogen environment is lower than that in ethanol vapor. During the whole evaporation process, the tangential temperature gradient and the normal temperature gradient alter as the variation of droplet height, and their relative magnitude determines the internal flow and the evolution of thermal patterns. Moreover, when ethanol vapor is absorbed by the water droplet, the heat of solution is released, and the solutal-Marangoni convection is induced to suppress the buoyancy flow.

Real world evaluation and control of vehicle engine exhaust air pollution using adaptive neural fuzzy inference system

Internal combustion engines are considered primarily responsible for air pollution. Accordingly, a concentrated effort has been made to reduce these pollutants which are emitted from the exhaust system of these engines while preserving energy and fuel consumption. There are also other sources besides internal combustion engines, such as power stations and those released from industry and home consumption. Industrial and household fuel consumers are also adding pollution. The industrial development requires the establishment of effective control systems to deal with its equipment to increase its operational life and increase its productivity with lower maintenance costs. Therefore, the aim of the study in this research is exposed to be used of adaptive neural fuzzy inference system to control the components of the emission of exhaust pollutants for gasoline vehicle. Exhaust pollutants consist of unburned carbon monoxide, hydrocarbons, carbon dioxide, water vapor nitrogen oxides, and energy produced from the combustion process which emit into atmosphere through the exhaust tailpipe. Also, there are hydrocarbons produced from gasoline vaporization and from the crankcase of the vehicle. The results indicate that the adaptive neural fuzzy inference system proves to be a useful tool for simulating and controlling vehicle engine exhaust emissions.

High Water-Assisted Proton Conductivities of Two Cadmium(II) Complexes Constructed from Zwitterionic Ligands.

Finding more metal complexes with outstanding water stability and high proton conductivity still has important research significance for the energy field. Herein, two highly proton-conductive complexes, one hydrogen-bonded supramolecular framework (HSF) [Cd(CBIA)2(H2O)4]·2H2O (1) and one coordination polymer (CP), {[Cd2(CBIA)2(4,4'-bipy)2(H2O)2]·(CBIA)·(OH)·2H2O}n (2) (4,4'-bipy = 4,4'-bipyridine), were triumphantly assembled using a zwitterionic organic compound, 2-(1-(carboxymethyl)-1H-benzo[d]imidazol-3-ium-3-yl)acetate (HCBIA). In the structure of HSF 1, there are several coordination and lattice H2O units except for the two monodentate CBIA- anions. CP 2 with a one-dimensional (1D) cylindrical structure has free CBIA- units and free H2O units located in the cavity. Thanks to the ability of the uncoordinated carboxyl groups and coordination/lattice water molecules to construct the rich H-bonding networks, both complexes exhibit super-high proton conductivities, reaching 5.09 × 10-3 and 3.41 × 10-3 S cm-1 under 100 °C/98% relative humidity (RH), respectively. Based on the exploration of crystal structure data, combined with the calculated activation energy, and adsorption/desorption plots of nitrogen and water vapor, the causes and differences in proton conductivity of the two complexes, especially the proton-conductive mechanism, are compared and analyzed. This study again confirms that the zwitterionic ligands can exert important effects on forming organo-inorganic hybrid materials with high proton conductivity.

The Effects of Different Doses of ROCK Inhibitor, Antifreeze Protein III, and Boron Added to Semen Extender on Semen Freezeability of Ankara Bucks.

In the presented study, the effects of ROCK inhibitor Y-27632, antifreeze protein III, and boron at two different doses were investigated on the spermatological parameters of Ankara buck semen after freeze-thawing. Ejaculates were collected from bucks using an electroejaculator during the breeding season. The ejaculates that showed appropriate characteristics were pooled and used in the dilution and freezing of semen. The extender groups were formed by adding two different doses of three different additives (ROCK inhibitor Y-27632, 5 and 20 µM; antifreeze protein III, 1 and 4 µg/mL; boron, 0.25 and 1 mM) to the control extender. The semen was diluted with the different extenders at 35-37 °C and loaded into straws. Sperm samples frozen in liquid nitrogen vapors, following equilibration, were stored in liquid nitrogen. It was observed that extender supplementation improved post-thaw motility of Ankara buck semen after freeze-thawing. Differences were significant (p &lt; 0.01) for 5 and 10 µM doses of ROCK inhibitor (71.82% and 74.04 % motility), as well as for 0.25 and 1 mM doses of boron (76.36% and 72.08% motility), compared to the control group (66.15% motility). With respect to the evaluation of acrosomal integrity and mitochondrial activity after freeze-thawing, although supplementation provided protection at all doses, the efficacy was not statistically significant (p &gt; 0.05). It was observed that DNA damage was improved by antifreeze protein III at 1 µg/mL (1.23% ± 0.23%) and by boron at all doses (0.25 mM: 1.83% and 1 mM: 1.18%) compared to the control group (3.37%) (p &lt; 0.01), following the thawing process. In the present study, it was determined that some additives added to the extender provided significant improvements in buck spermatozoa motility and DNA damage after thawing.

Effect of Melatonin and Caffeine Supplementation to Freezing Medium on Cryosurvival of Peruvian Paso Horse Sperm Using a Two-Step Accelerating Cooling Rate.

This research examined the antioxidant and cryoprotective effects of melatonin (ME) and caffeine (CAF) supplementation in freezing medium on the cryosurvival of Peruvian Paso horse sperm using a two-step accelerating cooling rate. Twenty ejaculates from four adult and fertile stallions were recovered, initially diluted with INRA-96®, and finally frozen with INRA-Freeze® with either no supplementation (as control), 1 μM ME, or 2 mM CAF using a two-ramp freezing system content inside a cryogenic-box and liquid nitrogen vapors. The sperm kinematic parameters and integrity of the plasma and acrosomal membranes of fresh semen and cryopreserved samples were evaluated using the CASA system (SCA-Evolution® 2018) and PI/fluorescein isothiocyanate-conjugated peanut (Arachis hypogaea) agglutinin double fluorescent test, respectively. The oxidative stress of post-thaw sperm samples was also assessed using the CellRox Deep Red fluorescence test. The results showed that curvilinear velocity and average-path velocity were greater (p < 0.05) after freezing with CAF than the control group. In addition, there were significance differences (p < 0.01) between stallions (1-4) in post-thaw kinematic parameters regardless of ME or CAF addition. Both ME and CAF improved (p < 0.05) the proportion of sperm with intact plasma membranes and intact acrosomes. Nevertheless, neither CAF nor ME improved the oxidative stress after the cryopreservation process.

Thermal Characteristics of Gaseous-Helium-Cooled HTS Cables With Practical Operating Conditions

High temperature superconducting (HTS) cables have the advantages of low loss and large capacity transmission. The cryogen used for HTS cable cooling is mainly liquid nitrogen. In some applications, using gaseous helium (GHe) as a cryogen has advantages. For example, it can reduce the weight of the system, remove the risk of frostbite of surrounding equipment and people caused by leakage of liquid nitrogen, and avoid suffocation due to evaporation of liquid nitrogen in confined spaces. Temperature is closely related to the performance of superconducting tapes. Therefore, it is of great significance to study the thermal characteristics of cables using GHe as cryogen under several important operating conditions. These conditions include cooling, carrying rated current, cryocooler fails, both cryocooler and cryogenic gas circulation pump fail, and local hot spot. In this article, a two-dimensional axisymmetric simulation model of a 50-m 4 kA HTS cable was built in COMSOL to study the thermal characteristics of GHe-cooled HTS cables. The range of mass flow rates of GHe suitable for operation of this cable was calculated considering different operating conditions.

Successful semen collection and cryopreservation of Banteng semen (Bos javanicus) using an artificial vagina

Gamete collection is feasible in Banteng (Bos javanicus) and is essential for conserving this species. The common practice of semen collection in wild animals is using the electroejaculation technique which is considered invasive with lower-quality results. This study aims to develop sperm collection further using an artificial vagina and to investigate the sperm motility of Banteng after being frozen-thawed. A Banteng bull kept in Taman Safari Indonesia was used for this study. Before semen collection, the bull is acclimatized to collection conditions. Semen collection is done once a month for six months. The semen was evaluated according to a method for bovine semen. Cryopreservation of semen was performed using an Andromed® extender, in 0.25 mL Ministraw®, and equilibrated at 4°C for 3 hours, followed by freezing in liquid nitrogen vapor. Quality testing was performed using the CASA IVOS II™. The result showed variations between batches, with the number of mountings 9.83±2.86(7-15) times, semen volume 8.42±1.42 (6-9) mL, straw produced 152±15.23 (130-172) straws, and total motility after thawing 44.28 ±12.14, (26.83-55.96). The quality of frozen semen of the later batch showed better results p<0.05. In conclusion, the collection of Banteng semen using an artificial vagina showed promising results with moderate quality.

Effects of Cell Concentration During Cryopreservation On the Post-thaw Quality of Santa Inês Ram Sperm

BACKGROUND: Non-surgical artificial insemination techniques for sheep may benefit from larger numbers of sperm in the insemination dose because the ewe's cervix is convoluted and often cannot be traversed with an insemination gun resulting in deposition of the sperm at the os cervix. OBJECTIVE: To compare a range of sperm concentrations when cryopreserving semen from Santa Inês rams and determine the effects of this on post-thaw quality. MATERIALS AND METHODS: One ejaculate from each ram (n = 10) was diluted to four sperm concentrations to obtain the following groups: G – 400, G – 800, G – 1200, and G – 1600 x 10 6 sperm/mL. The semen samples were packaged in 0.25 mL straws, cooled to 5 ºC, cryopreserved in liquid nitrogen vapor, thawed in a water bath (40 ºC/20 s), and were analyzed for computerized kinetics, capacitation and acrosome integrity, and plasma membrane integrity of sperm. RESULTS: The G – 400 treatment resulted in samples with the highest linearity and progressive motion (P &lt; 0.05) and had significantly greater plasma membrane integrity, and lower capacitation and acrosome reaction rates compared to G-1600 (P &lt; 0.05). Overall, use of the G – 400 treatment resulted in better kinetics, less plasma membrane damage and less early capacitation. However, despite reducing the ejaculate yield and increasing the costs of the semen freezing process, the G – 800 and G – 1200 treatments make a greater absolute number of sperm with good kinetics, plasma membrane integrity and capacitation status available. CONCLUSION: Ram sperm concentration impacts cryopreservation, and higher concentrations may be advantageous if a single rtificial insemination protocol is desirable.

Upgrading Monocytes Therapy for Critical Limb Ischemia Patient Treatment: Pre-Clinical and GMP-Validation Aspects.

Advanced cell therapy medicinal products (ATMP) are at the forefront of a new range of biopharmaceuticals. The use of ATMP has evolved and increased in the last decades, representing a new approach to treating diseases that are not effectively managed with conventional treatments. The standard worldwide recognized for drug production is the Good Manufacturing Practices (GMP), widely used in the pharma production of synthesized drugs but applying also to ATMP. GMP guidelines are worldwide recognized standards to manufacture medicinal products to guarantee high quality, safety, and efficacy. In this report, we describe the pre-clinical and the GMP upgrade of peripheral blood mononuclear cell (PBMC) preparation, starting from peripheral blood and ending up with a GMP-grade clinical product ready to be used in patients with critical limb ischemia (CLI). We also evaluated production in hypoxic conditions to increase PBMC functional activity and angiogenic potential. Furthermore, we extensively analyzed the storage and transport conditions of the final product as required by the regulatory body for ATMPs. Altogether, results suggest that the whole manufacturing process can be performed for clinical application. Peripheral blood collected by a physician should be transported at room temperature, and PBMCs should be isolated in a clean room within 8 h of venipuncture. Frozen cells can be stored in nitrogen vapors and thawed for up to 12 months. PBMCs resuspended in 5% human albumin solution should be stored and transported at 4 °C before injection in patients within 24 h to thawing. Hypoxic conditioning of PBMCs should be implemented for clinical application, as it showed a significant enhancement of PBMC functional activity, in particular with increased adhesion, migration, and oxidative stress resistance. We demonstrated the feasibility and the quality of a GMP-enriched suspension of monocytes as an ATMP, tested in a clean room facility for all aspects related to production in respect of all the GMP criteria that allow its use as an ATMP. We think that these results could ease the way to the clinical application of ATMPs.

Effects of different deodorization methods on the oxidation of sterol components in rice bran oil

Rice bran oil contains a significant quantity of phytosterols that have various active functions and are natural active substances beneficial to humans. It is well known that deodorization during refining affects the quality of rice bran oil. However, changes in phytosterols fraction caused by stripping with nitrogen compared to water vapor remain unexplored. We measured phytosterols in rice bran oil after deodorization with nitrogen and water vapor. The variations in sitosterol fraction, which accounts for the highest percentage of phytosterols in rice bran oil, were analyzed by Gas chromatography (GC), Fourier transform infrared spectrometer (FTIR), and Nuclear magnetic resonance (NMR). Results showed that using nitrogen as the stripping gas was more suitable for deodorization. It promoted the formation of phytosterol esters, reduced the production of phytosterol oxidation products and improved the oil quality. This study provides a theoretical basis for improving the industrial production quality of rice bran oil.

Effects of adding mixed chicken and quail egg yolks to the cryodiluent on the quality of ram semen before and after cryopreservation.

The effects of adding mixed chicken and Japanese quail egg yolks (EYs) to the cryodiluent on the quality of ram semen before freezing and post-thawing were evaluated. Additionally, the composition of chicken and quail egg EYs and their mixture were analyzed for results explanation. The semen was collected from rams (n = 5) and extended with cryodiluent containing the EY of chicken, quail or their mixture (1:1). The extended semen was chilled slowly to 5 °C within 2 h and equilibrated for 2 h, before frozen on the liquid nitrogen vapor and cryopreserved at −196 °C. The straws were evaluated before freezing and post-thawing for sperm motility, vitality and abnormality besides plasma-membrane and DNA integrities. The moisture, ash, protein, and fatty acid (FA) contents of chicken EY, quail EY and their mixture were analyzed. Sperm vitality, plasma membrane integrity and DNA integrity before freezing were significantly (P < 0.05) higher in quail EY than chicken EY and mixed EYs cryodiluent. The chicken EY extender significantly improved the vitality, plasma membrane and DNA integrities of post-thawed ram semen in comparison with quail EY or mixed EYs extenders. While, the post-thawing sperm abnormalities was lower (P ≤ 0.05) in quail EY than chicken EY and mixed EYs cryodiluent. The post-thawing sperm motion kinetics parameters were higher in quail EY than chicken EY and mixed EYs cryodiluent. The highest percentages of moisture, ash, saturated fatty acids (SFAs) and monounsaturated fatty acids (MUFAs) were detected in quail EY had. While, the highest percentages of fat, protein and polyunsaturated fatty acids (PUFAs) were detected in chicken EY. In conclusion, using of chicken EY can improve total motility, vitality, plasma membrane integrity and DNA integrity of cryopreserved ram semen. While, using of quail EY can improve sperm abnormalities and kinetic motion parameters of cryopreserved ram semen. Mixing chicken and quail EYs added no value for post-thawing ram semen parameters.

Example for process validation in biobanking: Fit for purpose testing of a cryopreservation method without isopentane.

Background: The freezing process of tissue samples is crucial for the preservation of morphological and molecular features. Several biobanking guidelines describe freezing techniques for optimal outcomes. As the Vetbiobank standard freezing protocol does not comply with those recommendations in detail, a process validation was performed to demonstrate that samples are suitable for downstream applications. Here we give a formal example of a process validation in the biobanking setting, as required by the biobanking guideline ISO 20387 (2018). Methods: Three different freezing protocols, freezing in liquid nitrogen, freezing via isopentane precooled on dry ice and freezing via liquid nitrogen vapor, were assessed based on morphological integrity of mouse liver and muscle tissue samples. Samples were either frozen in cryotubes (without Optimal Cutting Temperature compound, OCT) or in cryomolds (with OCT). The protocol providing the best results was validated for reproducibility and robustness in terms of defined acceptance criteria for morphological evaluability, A260/A280 ratio, and RNA integrity number values (RIN). In addition, performance tests were run by gene expression analyzes of selected, tissue specific biomarkers to confirm that processed samples are fit for purpose. Results: From the three applied freezing protocols, freezing in liquid nitrogen generated best results. Reproducibility acceptance criteria were met for both, morphological integrity and RNA quality. The freezing method was robust for the tested tissue types and the application of OCT, with exception of liver tissue, where it led to a significant decrease of the RIN value. Gene expression analyzes showed good comparability of results regardless of the applied freezing method. Conclusion: Freezing of tissue samples in liquid nitrogen provides samples of adequate quality for subsequent RNA investigations. A negative impact of OCT on the RIN value of liver samples was observed, which was independent from the applied freezing protocol and showed no impact on subsequent gene expression analysis.

STUDY OF CHEMICAL CHARACTERISTICS OF BLACKCURRANT BERRIES DURING TREATMENT WITH LIQUID NITROGEN

This article presents some aspects related to the freezing of blackcurrant berries using liquid nitrogen: the duration of the process, the analysis of frozen and thawed berries, the change in physicochemical parameters and chemical composition, the advantages and disadvantages of this modern method. Fast freezing of food products in a cryogenic freezer is based on the use of the latent heat of vaporization of liquid nitrogen, as well as the sensible heat of vapors, the temperature of which rises to the final temperature of the frozen product. Given the requirement to reduce the fuel consumption required to generate the electricity needed for classical refrigeration systems, this method is used to freeze liquid nitrogen obtained as a by-product in the production of oxygen. Black currant is one of the most valuable and affordable sources of high content of vitamins and biologically active polyphenols. In the list of traditional berry plants, this crop occupies one of the leading positions in terms of the content of nutrients and biologically active substances necessary for a balanced human diet. Modern standards for blackcurrant varieties necessarily include certain requirements for the quality of berries, including their biological composition.