Equipment for Rapid Freezing of Oil Contaminated Soil by Liquid Nitrogen for Its Subsequent Utilization

2021 ◽  
Vol 57 (5-6) ◽  
pp. 398-402
Author(s):  
K. P. Venger ◽  
V. A. Stefanova ◽  
O. A. Feskov ◽  
M. A. Romanov
1979 ◽  
Vol 83 (1) ◽  
pp. 31-39 ◽  
Author(s):  
JOHN H. BOOTH

Injecting vitally stained blood cells into the ventral aorta of unrestrained, cannulated fish, and rapid freezing in liquid nitrogen, permitted the examination of the effects of oxygen supply, epinephrine and acetylcholine on branchial lamellar perfusion. Compared to the conditions in resting fish in air-saturated water, hypoxia and injection of epinephrine significantly increased the proportion of secondary lamellae receiving stained cells, and acetylcholine caused a significant reduction, but hyperoxia did not significantly affect the proportion of lamellae containing stained cells. Perfusion of the filamental central compartment was not affected by the treatments. It is concluded that trout can respond to changes in oxygen supply by varying the number of secondary lamellae perfused with blood, and that the distribution of blood flow is regulated by cholinergic and adrenergic receptors. It is suggested, however, that lamellar recruitment would not be useful in minimizing the costs of osmo- and iono-regulation.


BioTechniques ◽  
2020 ◽  
Vol 69 (6) ◽  
pp. 450-454
Author(s):  
Lara Dutra ◽  
Ole Franz ◽  
Veli-Mikko Puupponen ◽  
Marja Tiirola

Droplet microfluidics is a technology that enables the production and manipulation of small volumes. In biosciences, the most popular application of this technology is Droplet Digital™ PCR (ddPCR™), where parallel nanoliter-scale PCR assays are used to provide a high sensitivity and specificity for DNA detection. However, the recovery of PCR products for downstream applications such as sequencing can be challenging due to the droplets' stability. Here we compared five methods for disrupting the droplets to recover DNA. We found that rapid freezing in liquid nitrogen results in a clear phase separation and recovery of up to 70% of the DNA content. Liquid nitrogen freezing can thus offer a simple and environmentally friendly protocol for recovering DNA from ddPCR.


1963 ◽  
Vol 10 (12) ◽  
pp. 515-517
Author(s):  
TAKEJIRO NAKAMURA ◽  
RENPEI JINNO

1991 ◽  
Vol 3 (2) ◽  
pp. 175 ◽  
Author(s):  
R Li ◽  
A Trounson

This study investigates the effects of time and temperature of exposure to a high concentration (4.5 M) of dimethyl sulfoxide (DMSO), glycerol, 1,2-propanediol (PROH), or a mixture of DMSO and glycerol (DG) in a solution containing 0.25 M sucrose, on the survival and development of rapidly frozen mouse blastocysts. Embryos had significantly (P less than 0.01) higher rates of survival and development when exposed to cryoprotectant at 0 degree C compared with room temperature. The time of exposure to cryoprotectant at either 0 degree C or room temperature before being plunged into liquid nitrogen significantly (P less than 0.01) affected the survival and development of frozen-thawed embryos. Survival and development of blastocysts in vitro and in vivo was significantly (P less than 0.05) higher when exposed at 0 degree C for 10 min to DG, DMSO and glycerol than to PROH. It is concluded that, unlike early-cleavage stage embryos, blastocysts need to be equilibrated at a low temperature (0 degree C) with high concentrations of cryoprotectant before rapid freezing. Exposure of blastocysts to 4.5 M cryoprotectant and 0.25 M sucrose at room temperature either was toxic or else markedly reduced their viability after freezing and thawing, depending on the duration of the initial exposure.


2020 ◽  
Vol 32 (2) ◽  
pp. 146
Author(s):  
L. Palazzese ◽  
D. A. Anzalone ◽  
P. Toschi ◽  
P. Loi

Semen lyophilisation is an interesting technique that might be a cheap alternative to long-term storage in liquid nitrogen. The first significant result of this method was achieved by Wakayama and Yanagimachi in the 1998 and demonstrated, for the first time, the birth of healthy mouse pups from epididymal freeze-dried (mouse) spermatozoa. The authors follow the lyophilisation technique, commonly used in the pharmaceutical and food industries, namely, deep freezing, which requires direct immersion of the semen sample into liquid nitrogen before vacuum drying. In this work, we focused on the freezing phase to improve and make the technique more reliable. We compared two protocols: 1) rapid freezing, where the semen is plunged directly into liquid nitrogen (LN group), and 2) slow freezing, where the sample is frozen with a freezing rate of 1°C min−1 until −50°C (SL group). Then, both frozen samples were lyophilized. Subsequently, after an interval ranging between 1 and 3 months, dry spermatozoa from LN and SL groups were used for intracytoplasmic sperm injection (ICSI), and the embryo development was evaluated at 24h (2-cell stage) and 7 days (expanded blastocyst) post-ICSI. Moreover, acrosome integrity was evaluated with Pisum sativum agglutinin (PSA) staining on part of the semen, immediately after freezing. The LN-group semen showed the acrosome completely melted, whereas the SL group showed better integrity of the acrosome, which was comparable to that of the normal frozen (vital) spermatozoa. At 24h post-ICSI the number of cleaved embryos in the SL group was higher than in the LN group (42/100 (42%) vs. 19/75 (25.3%), SL and LN, respectively; P=0.0253). The blastocyst rate 7 days after ICSI in the SL group was higher (7/100 (7%) than that in the LN group (2/75 (2.7%); P=0.0238). Our data show that lyophilisation can be conveniently achieved in ram spermatozoa without liquid nitrogen, thus simplifying the procedure. These data support the idea that lyophilisation might be a valuable and cheaper alternative to liquid nitrogen for long-term storage of ram semen.


2016 ◽  
Vol 2 (2) ◽  
pp. 31
Author(s):  
Enny Sudarmonowati ◽  
I. Fitryatmi ◽  
S. Sadjad

<br />Study on cryopreservation of Indonesian local cultivars and improved  varieties of maize and soybean has never been done. This method may be used for long-term preservation of seeds of maize and soybean. In this study, the method was applied to maize and soybean, Arjuna and Wilis respectively, as a model for preserving germplasm of ortodox seeds. Whole seeds and excised embryos of both varieties were subjected to two methods of cryopreservation, i.e., two-stage cooling and rapid freezing with or without 15% dimethyl sulfoxide (DMSO) as cryoprotectant solution prior to immersion in liquid nitrogen (-196oC). Results indicated that there was no significant difference between the use of DMSO for both species in terms of viability, although pretreatment in DMSO was slightly reduced the percentage of viability of both species. Slow freezing to -30oC prior to immersion in the liquid nitrogen could give as high as 76.67% and 51.67% surviving whole seeds of maize and soybean, respectively. Preserving excised embryos of maize in the liquid nitrogen using either slow or rapid freezing significantly reduced the percentage of viability from 20-76.67% to 5-18.33% (four folds) depending on treatments applied. Results also showed that one day or 15 minutes of immersion of samples in the liquid nitrogen gave rise to similar values of viability of maize and soybean, i.e., 20-60% and 20-51.67%, respectively depending on  treatments applied. These results implied that for long-term storage of maize and soybean seeds as they could survive at the rate of 76.67% and 51.67% respectively, the seed can be treated by prefreezing to -30oC<br />without the presence of DMSO prior to immersion in liquid nitrogen.<br /><br />


PEDIATRICS ◽  
1975 ◽  
Vol 56 (3) ◽  
pp. 429-433
Author(s):  
Patricia V. Donnelly ◽  
Nicola Di Ferrante

Skin fibroblasts from three obligated and one potential heterozygotes for the Hunter gene displayed abnormal metabolism of glycosaminoglycans four to six weeks after rapid freezing in liquid nitrogen. The technique seems to be useful for the identification of Hunter carriers, especially when the degradation of 35SO4-labeled, intracellular glycosaminoglycans, rather than the uptake 35SO4, is measured.


Zygote ◽  
2003 ◽  
Vol 11 (4) ◽  
pp. 361-366 ◽  
Author(s):  
Csaba Pribenszky ◽  
Sándor Cseh ◽  
Zsolt Abonyi-Tóth ◽  
László Solti

The objective of the present study was to examine the effect of rapid freezing on the in vitro and in vivo survival of zona-pellucida-free hatched mouse blastocysts. Hatched blastocysts were rapidly frozen in a freezing medium containing either ethylene glycol (EG) or glycerol (G) in 1.5 M or 3 M concentration. Prior to freezing, embryos were equilibrated in the freezing medium for 2 min, 10 min, 20 min or 30 min at room temperature. To freeze them, embryos were held in liquid nitrogen vapour [≈1 cm above the surface of the liquid nitrogen (LN2)] for 2 minutes and then immersed into LN2. After thawing, embryos were transferred either to rehydration medium (DPBS + 10% foetal calf serum + 0.5 M sucrose) for 10 minutes or rehydrated directly in DPBS supplemented with foetal calf serum. In vitro survival of embryos frozen with EG was higher than those frozen with G. The highest survival was obtained with 3 M EG and 2 min or 10 min equilibration prior to freezing, combined with direct rehydration after thawing. Frozen blastocysts developed into normal foetuses as well as unfrozen control ones did, with averages of 30% (control), 26% (EG) and 15% (G). The results show that hatching and hatched mouse blastocysts can be cryopreserved by a simple rapid freezing protocol in EG without significant loss of viability. Our data indicate that the mechanical protection of the zona pellucida is not needed during freezing in these stages.


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