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Source publication
Purpose
To determine liquid nitrogen evaporation rates of intact liquid nitrogen storage tanks and tanks with their vacuum removed.
Methods
Donated storage tank performance (LN2 evaporation) was evaluated before and after induced vacuum failure. Vacuum of each tank was removed by drilling through the vacuum port. Temperature probes were placed 2 i...
Contexts in source publication
Context 1
... tanks used for this study were donated, as use of new and multiple tanks was prohibitive; no inclusion or exclusion criteria applied to use of any tank donated for this study. Characteristics of these tanks are described in Table 1. ...Context 2
... most dramatic result from the small tanks was that the evaporation rate went from less than a liter per day to at least 40 L per day within the first 6 h after drilling to remove the vacuum (Table 1). This rate slowly declined as the tank's liquid nitrogen became depleted. ...Context 3
... note, there was a difference in evaporation rates postfailure between two very similar tanks, tanks 2 and 3. Tank 3 had a much higher mean evaporation rate (see Table 1). Both tanks were model MVE 47/11, but note that tank 3 had been fit with a complete storage rack system: cannisters, canes, and goblets to simulate a full inventory. ...Context 4
... tanks used for this study were donated, as use of new and multiple tanks was prohibitive; no inclusion or exclusion criteria applied to use of any tank donated for this study. Characteristics of these tanks are described in Table 1. ...Context 5
... most dramatic result from the small tanks was that the evaporation rate went from less than a liter per day to at least 40 L per day within the first 6 h after drilling to remove the vacuum (Table 1). This rate slowly declined as the tank's liquid nitrogen became depleted. ...Context 6
... note, there was a difference in evaporation rates postfailure between two very similar tanks, tanks 2 and 3. Tank 3 had a much higher mean evaporation rate (see Table 1). Both tanks were model MVE 47/11, but note that tank 3 had been fit with a complete storage rack system: cannisters, canes, and goblets to simulate a full inventory. ...Similar publications
O objetivo foi avaliar a influência da conservação [refrigeração a 5°C e vitrificação] sobre tecidos somáticos de catetos. O experimento foi dividido em duas etapas. Na primeira etapa, fragmentos foram refrigerados por 24 (R-24) e 48 h (R-48) e comparados com amostras não refrigeradas (C). Na segunda etapa, fragmentos foram refrigerados por 24 (RV-...
![Figure 2: Calculated percentages of supercooled intracellular water [2]](profile/Anirban-Bhattacharya-2/publication/358915252/figure/fig2/AS:1136493208838144@1647972504285/Calculated-percentages-of-supercooled-intracellular-water-2_Q320.jpg)
Citations
... This suggests that tank 2 is more efficient in maintaining the weekly amount of LN 2 . Pomeroy et al. (2019) reported that the designs of LN 2 tanks (e.g. size, shape, construction materials, welds, and sealants) do not prevent the loss of the tank's structural integrity. ...
... Regular maintenance (e.g. monitoring of tank weights and liquid gas levels) varies from laboratory to laboratory and may involve daily or weekly inspections (Pomeroy et al., 2019). With proper handling, most tanks will last for years but all liquid nitrogen tanks will eventually fail due to aging and loss of vacuum (DuPonte, 2007). ...
Background: The integrity of storage tanks is essential in maintaining the liquid nitrogen used to preserve buffalo semen straws later utilized for artificial insemination. Faulty semen handling procedures, and equipment maintenance damage the spermatozoa leading to low-quality semen and low conception rates.
Methods: The study used two brands of liquid nitrogen tanks and four purebred mature Bulgarian Murrah buffaloes. The semen samples were collected twice a week and immediately processed by the center’s laboratory technician following a slow freezing technique. After processing, the semen straws were stored in LN2 tanks at -196°C.
Result: Results revealed that tank 2 was more efficient in maintaining the weekly amount of LN2 and the frequent opening of tank covers significantly (P<0.05) decreased the quantity of LN2 after four days. Moreover, the different brands of LN2 tanks did not affect sperm motility and livability, however, the frequency of exposing the semen straws to ambient temperature for 5 and 10 seconds lowered the sperm quality. In conclusion, semen straws should not be exposed to ambient temperature beyond the recommended time due to its deleterious effect on the semen quality compromising the success of insemination.
... Although several factors govern the evaporation rate of LN 2 from cryogenic storage tanks, the integrity of the insulating vacuum jacket seal is the most critical. For a full review of the risk of sample loss due to tank failure and best practices for mitigating risk, see Pomeroy et al. (2019). ...
Fungi occupy important environmental, cultural, and socioeconomic roles. However, biological research of this diverse kingdom has lagged behind that of other phylogenetic groups. This is partially the result of the notorious difficulty in culturing a diverse array of filamentous fungal species due to their (i) often unpredictable growth, (ii) unknown preferences for culturing conditions, and (iii) long incubation times compared with other microorganisms such as bacteria and yeasts. Given the complexity associated with concurrently culturing diverse fungal species, developing practical methods for preserving as many species as possible for future research is vital. The widely accepted best practice for preserving fungal tissue is the use of cryogenic biobanking at -165 C, allowing for the preservation and documentation of stable genetic lineages, thus enabling long-term diversity-centered research. Despite the extensive literature on fungal cryopreservation, substantial barriers remain for implementation of cryogenic biobanks in smaller mycological laboratories. In this work, we present practical considerations for the establishment of a fungal culture biobank, as well as provide evidence for the viability of 61 fungal genera in cryogenic storage. By providing a pragmatic methodology for cryogenically preserving and managing many filamentous fungi, we show that creating a biobank can be economical for independently owned and operated mycology laboratories, which can serve as a long-term resource for biodiversity, conservation, and strain maintenance.
... cryopreserved material stored at cryogenic temperatures (around À196°C) for longer and longer periods (Abreau et al., 2021) and an infrastructure that for the most part was not designed to handle such large volumes (Alikani and Parmegiani, 2018). The most common cryostorage formats are small dewars (30À73 litre capacity), the basic design of which dates to James Dewar in the late 19th century, and larger stainless-steel tanks (160À1000 litre capacity) for 'bulk' storage (Pomeroy et al., 2019). Small dewars are filled with LN2 and maintained manually, while the larger tanks are usually equipped with automatic filling systems and can function with either LN2 or nitrogen in the vapour phase. ...
... Its operation loss is very low, so that the coil can be sufficiently cooled in a cryogenic tank filled with liquid nitrogen without the need of a cryocooler. Taking the loss of commercial liquid nitrogen container as a reference, it is not difficult to achieve a daily loss rate of less than 2% [62]. Consequently, the capital cost of the new superconducting coil will be much lower than that of an SMES. ...
Regenerative braking technology has become increasingly attractive due to its ability to recover and reuse the energy that would otherwise be lost. In recent years, a new superconducting energy storage technology is proposed and it has been proved experimentally and analytically that the technology has promising application potential in urban rail transit for regenerative braking. However, a comprehensive assessment of the new technology has not been conducted up to date. In this paper, the currently available energy storage technologies for regenerative braking, such as batteries, supercapacitors, flywheels, and SMES are introduced along with the new superconducting energy storage technology. Comparative studies between the existing technologies and the new one are conducted in terms of energy density, energy conversion efficiency, energy storage duration, capital cost and environmental impact. It is concluded that a regenerative braking system with the new superconducting energy storage has very high cycle efficiency and is superior to the existing energy storage systems. It has the potential to revolutionize the regenerative braking technology and to develop more efficient and sustainable urban rail transportation systems.
... The macromolecular diffusion was inhibited, and thermo-mechanical stresses were reduced under Tg [26], limiting the chemical changes in the vitrified embryo. In our laboratory, we monitor the LN 2 level of the LN 2 tank twice a week and keep the tank full with LN 2 , avoiding temperature change that might be caused by LN 2 evaporation [27,28]. However, repeated retrieval of the embryo from the LN 2 tank in the process of practical application during cryopreservation may alter the temperature. ...
Background
Cryopreservation of embryos plays a major role in the in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) treatment. However, the storage condition of the cryopreserved embryo can change temporarily due to repeated retrieval of the embryo from the liquid nitrogen (LN2) tank during the practical application during cryopreservation. Whether the implantation potential of a cryopreserved embryo will be damaged when the cane containing it is temporarily exposed to air due to the transfer between the LN2 tank and LN2 container is yet to be elucidated. Also, whether the exposed-to-air frequency (EAF) of cryopreserved embryos influences the clinical outcomes is unclear.
Objective
To investigate whether the EAF of cryopreserved embryo affects the clinical outcomes of vitrified-warmed embryo transfer.
Methods
A total of 9200 vitrified-warmed embryo transfer cycles were included in this study. All cycles were divided into five groups according to different EAFs (2, 4, 6, 8, or ≥ 10). Post-warming survival rates and clinical outcomes, including implantation, clinical pregnancy and live birth rates were investigated. Kruskal–Wallis test and Pearson’s chi-squared tests were used to compare the patient characteristics and clinical outcomes among the five groups. Furthermore, multivariate logistic regression analyses were conducted to investigate the association between EAF and clinical outcomes.
Results
No significant differences were observed in the positive HCG rate, implantation rate and live birth rate (P > 0.05) among five EAF groups with respect to D3 embryo, D5 blastocyst and D6 blastocyst. Post-warmed survival rate of D3 embryos (P = 0.015) differed significantly among the five EAF groups, but it was not EAF-dependent. Although clinical pregnancy was different among the five groups with respect to D5 blastocyst (P = 0.042), multivariate logistic regression analysis adjusted for confounding variables suggested that EAF did not adversely affect clinical pregnancy or live birth.
Conclusion
These findings indicated that human vitrified embryos in the open system could be repeatedly retrieved from the LN2 tank without affecting the implantation potential of the embryo.
... Cryostorage tank failures have been previously reported, but most were simulated or induced to evaluate a vacuum loss failure. 4,5 To the best of our knowledge, this is the first study to report a real vapor ST failure, leading to an unexpected accumulation of LN2. The data provided by this study are unique and should be considered when evaluating the cryopreserved CT product storage procedure, including monitoring and detection of a failing ST. ...
... d) Direct gas convection, and radiation through the mouth opening Minimization of these sources of heat in leak into the systems gives minimum evaporation loss of cryogen during storage In the present case, super insulation i.e., several layers of aluminized mylar with 12-micron thickness is used as a reflecting shield along with a vacuum in the annular space to reduce the rate of evaporation. Measurement of loss of cryogen from the Dewar is an indication of the efficiency of the storage vessel [3][4] . ...
Heat is transferred across the annular space of a vacuum-insulated cryogenic vessel by radiation from the hot outer jacket to the cold inner vessel and by gaseous conduction through the residual gas within the annular space. Hence to minimize gaseous conduction, the annular space is degassed at an elevated temperature during the evacuation, and a very high vacuum (10-6 Torr) is maintained. The inner vessel is further wrapped with several layers of radiation shields resulting in a Multilayer insulation system which is the most effective thermal insulation for cryogenic storage vessels. The effectiveness of cryogenic insulation of a cryo container is more often judged by the evaporation rate of the cryogen. In this regard, static evaporation losses of liquid nitrogen from a small indigenously built Cryocan Dewar with respect to time by using a continuous weight loss method are presented. The results are encouraging.
... . While research groups are deciphering the complexities of cryopreservation, long-term storage at low temperatures still involves significant costs in electricity for ultracold freezers, liquid nitrogen supply, monitoring of storage containers, maintenance, and specialized facilities. Even when institutions can cover the expenses, cryostorage systems are prone to failures-from equipment breakdown to human errorwhich has led to dramatic sample losses in human fertility clinics and research laboratories (Letterie & Fox, 2020;Pomeroy et al., 2019). ...
Long-term preservation of sperm, oocytes, and gonadal tissues at ambient temperatures has the potential to lower the costs and simplify biobanking in human reproductive medicine, as well as for the management of animal populations. Over the past decades, different dehydration protocols and long-term storage solutions at nonfreezing temperatures have been explored, mainly for mammalian sperm cells. Oocytes and gonadal tissues are more challenging to dehydrate so little to no progress have been made. Currently, the detrimental effects of the drying process itself are better characterized than the impact of long-term storage at nonfreezing temperatures. While structural and functional properties of germ cells can be preserved after dehydration, a long list of damages and stresses in nuclei, organelles, and cytoplasmic membranes have been reported and sometimes mitigated. Characterizing those damages and better understanding the response of germ cells and tissues to the stress of dehydration is fundamental. It will contribute to the development of optimal protocols while proving the safety of alternative storage options for fertility preservation. The objective of this review is to (1) document the types of damages and stress responses, as well as their mitigation in cells dried with different techniques, and (2) propose new research directions.
... Cryostorage tank failures have been previously reported, but most were simulated or induced to evaluate a vacuum loss failure. 4,5 To the best of our knowledge, this is the first study to report a real vapor ST failure, leading to an unexpected accumulation of LN2. The data provided by this study are unique and should be considered when evaluating the cryopreserved CT product storage procedure, including monitoring and detection of a failing ST. ...
Aim
Cryopreserved cell therapy products are usually stored in vapor or liquid storage tanks to maintain long-term viability. Storage tank (ST) failure can lead to the loss of cryopreserved cell therapy (CT) products, which means the only possibility of treating serious illnesses. We aimed to describe a serious vapor ST failure, as well as the improvements implemented in the storage procedure to increase the safety and quality of cryopreserved CT products.
Method
This is a case report of a vapor ST failure (CBS, isothermal V5000-AB series). The records were reviewed to obtain information regarding the frozen units.
Results
On 07-dec-2021, the technical staff observed the accumulation of liquid nitrogen (LN2) at the bottom of the ST. The engineering team was contacted and adjusted the ST's maximum LN2 level. The problem recurred on 23-dec-2021. The engineering and maintenance company carried out a series of tests on the ST. On 06-Jan-2022, it was requested emptying and defrosting of the ST for 48 hours for corrective maintenance of the LN2 level sensor. Planning to transfer the inventory to another ST was started, including bags with serology/NAT reagent overwrapping. However, on 23-Jan-2022 (Sunday), the LN2 level sensor stuck at level zero leading the automated LN2 filling of the ST to start and not stop. There was an overflow of LN2 inside the vapor ST, and 3 of 4 rack positions were submerged in LN2. The engineering team performed the filling interruption manually, after being called by the concierge. There were 553 frozen bags from 307 patients/donors stored in the ST at the time of failure. Out of the 553 bags, 87 (15.7%) had positive serology or NAT tests. Of these, 11 (1.9%) were anti-HIV positive (NAT HIV negative) and two (0.3%) were HBsAg and NAT HBV reagents. Out of the 553 bags, 10 (1.8%) had a positive microbiological test, including four (0.7%) for multi-sensitive Salmonella sp. Excess of LN2 was manually removed from the ST and the actions to transfer the inventory to the backup ST were intensified, including changing the bags with positive tests (PT) to positions A or B of the racks, as well as finishing these bags overwrapping. The inventory was transferred and stored in the backup ST for approximately 72 hours. Surveillance actions were performed, including virtual meeting and discussion with the Brazilian National Health Surveillance Agency, visual examination to disclose leaking or breakage of seals, thawing of the unit with positive HBV NAT (authorized disposal) to confirm the absence of leaking or breakage of seals, monitoring external signs of vacuum loss, and discussion of the possibility of cross-contamination with the bag supplier.
Discussion
The data provided by this study are unique and should be considered when evaluating the cryopreserved cell therapy products storage procedure, including ST monitoring, detection of a failing ST, and contingency plan. After this ST failure, improvement actions in the storage procedure were implemented in our institution, including the modification of the storage location of the bags in quarantine and those with PT (positions A and B of the rack) and implementation of the routine use of overwrap in bags with PT. All activities conducted to resolve the issue and the improve actions were documented in non-compliance.
Conclusion
Vapor ST may fail, leading to an unexpected accumulation of LN2. Improvements in the storage procedure can avoid the serious consequences of this failure, including cross-contamination.
... A full-proof system must also be kept in place by clinics concerned to help avoid mishaps into their systems. 2 For this purpose, the exact storage location and maintenance of records in terms of tank name and number, canister number and location (column/row/level), and unique cane ID are mandatory. Optimum quality control is essential for any quality maintenance system that must be supervised by senior staff within the system. ...
