Coal cleat network evolution through liquid nitrogen freeze-thaw cycling

Cryoablation under endoscopic control is considered to be a promising approach in therapy of benign nodules of thyroid gland (TG). However, pathologically altered TG tissue differs in thermal conductivity and heat capacity from normal one, therefore the model experiments in animals are necessary to determine the cryoablation parameters. In this research, the changes of temperature during cryoablation of experimental rat TG under normal conditions and the one with propylthiouracil (PTU)-induced diffuse hyperplasia (DH) were comparatively assessed. TG was cryo-ablated in rats, previously received a 0.1% PTU solution within 90 days, using a copper cryoprobe, cooled to liquid nitrogen temperature. The process was controlled using thermocouples placed at different distances from the iceball. Differences between thermograms of intact TG tissue and the samples with PTU-induced DH were established. To achieve the destruction effect of TG with DH to a depth of more than 1 mm, the need of implementing two freeze-thaw cycles with 120-second cryoprobe exposure was proven.

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Successful transfusion of platelets cryopreserved for more than 3 years

Blood ◽

10.1182/blood.v54.5.1023.1023 ◽

1979 ◽

Vol 54 (5) ◽

pp. 1023-1027 ◽

Cited By ~ 41

Author(s):

PA Daly ◽

CA Schiffer ◽

J Aisner ◽

PH Wiernik

Keyword(s):

Platelet Count ◽

Liquid Nitrogen ◽

Vapor Phase ◽

Freeze Thaw ◽

Cryoprotective Agent ◽

Duration Of Storage ◽

Hla Type ◽

The Mean ◽

Emergency Transfusion

Abstract To determine the duration of storage for cryopreserved platelets, 14 transfusions of random-donor, pooled platelets, stored in the vapor phase of liquid nitrogen for a mean period of 1157 days (range 1060- 1240), were analyzed. Twelve of these transfusions were compared in a paired fashion with fresh, random-donor, pooled platelets given within a few days to the same thrombocytopenic recipients. Platelets had been frozen using 5% dimethylsulfoxide as a cryoprotective agent either at a controlled rate of -1 degrees C/min to -80 degrees C or by simply placing them in the vapor phase (-120 degrees C) of a liquid nitrogen freezer. The mean freeze-thaw loss for the 14 transfusions was 22%, and the mean corrected 1-hr increment in platelet count was 12,600/microliter. In the 12 paired observations, the mean corrected 1- hr increment for frozen platelets was 11,800/microliter and 25,900 for fresh platelets, giving a frozen/fresh recovery of 46%. Random donor platelets can be cryopreserved by these methods for greater than 3 yr with satisfactory post-transfusion increments. This suggests that a reservoir of frozen platelets, either random-donor for emergency transfusion or of known HLA-type for transfusion to alloimmunized patients, can be established and stored for at least 3 yr.

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Pore-scale analysis of coal cleat network evolution through liquid nitrogen treatment: A Micro-Computed Tomography investigation

International Journal of Coal Geology ◽

10.1016/j.coal.2019.103370 ◽

2020 ◽

Vol 219 ◽

pp. 103370 ◽

Cited By ~ 12

Author(s):

Hamed Akhondzadeh ◽

Alireza Keshavarz ◽

Ahmed Z. Al-Yaseri ◽

Muhammad Ali ◽

Faisal Ur Rahman Awan ◽

...

Keyword(s):

Computed Tomography ◽

Liquid Nitrogen ◽

Network Evolution ◽

Scale Analysis ◽

Pore Scale ◽

Micro Computed Tomography ◽

Nitrogen Treatment

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Nuclear magnetic resonance study of the influence of the liquid nitrogen freeze‐thaw process on the pore structure of anthracite coal

Energy Science & Engineering ◽

10.1002/ese3.624 ◽

2020 ◽

Vol 8 (5) ◽

pp. 1681-1692

Author(s):

Yapei Chu ◽

Haitao Sun ◽

Dongming Zhang ◽

Guo Yu

Keyword(s):

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

Pore Structure ◽

Liquid Nitrogen ◽

Nuclear Magnetic Resonance Study ◽

Magnetic Resonance Study ◽

Freeze Thaw ◽

Anthracite Coal ◽

Nuclear Magnetic

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Pore Damage Properties and Permeability Change of Coal Caused by Freeze-Thaw Action of Liquid Nitrogen

Advances in Civil Engineering ◽

10.1155/2018/5076391 ◽

2018 ◽

Vol 2018 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Bo Li ◽

Lulu Zhang ◽

Jianping Wei ◽

Yongjie Ren

Keyword(s):

Pore Structure ◽

Liquid Nitrogen ◽

Cold Shock ◽

Water Saturation ◽

Temperature Drop ◽

Freeze Thaw ◽

Thaw Cycle ◽

Before And After ◽

Porosity And Permeability ◽

Coal Rock

A laboratory test was conducted to investigate the effect of the freeze-thaw action of liquid nitrogen on the pore structure and permeability of coal rock. First, coal rock samples with similar sound velocities and permeabilities were selected. These samples were prepared in different water saturation levels and subjected to nuclear magnetic resonance (NMR) test before and after the freeze-thaw action. Furthermore, the freeze-thaw cycle of liquid nitrogen, freezing time, and water saturation of coal rocks were controlled in permeability test. Results showed that the pore diameter, porosity, and permeability of the coal rocks increase after the freeze-thaw action of liquid nitrogen. These characteristics increase further with the increase of water saturation. The fracturing mechanisms of the freeze-thaw action of liquid nitrogen were summarized in two aspects, phase change of pore water and cold shock, and cold shock was mainly discussed. The results indicate that the effect of cold shock is still crucial at low water saturation, but it is limited by the degree of temperature drop. In general, freeze-thaw action of liquid nitrogen can cause damage to pore structure, promote the formation of fracture networks, and consequently improve the permeability of coal rock.

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Damage caused by freeze‐thaw treatment with liquid nitrogen on pore and fracture structures in a water‐bearing coal mass

Energy Science & Engineering ◽

10.1002/ese3.623 ◽

2020 ◽

Vol 8 (5) ◽

pp. 1667-1680 ◽

Cited By ~ 2

Author(s):

Haifei Lin ◽

Jinliang Li ◽

Min Yan ◽

Shugang Li ◽

Lei Qin ◽

...

Keyword(s):

Liquid Nitrogen ◽

Coal Mass ◽

Freeze Thaw

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Freeze-Thaw Pretreatment Can Improve Efficiency of Bacterial DNA Extraction From Meconium

Frontiers in Microbiology ◽

10.3389/fmicb.2021.753688 ◽

2021 ◽

Vol 12 ◽

Author(s):

Yuntian Xin ◽

Jingxian Xie ◽

Bingru Nan ◽

Chen Tang ◽

Yunshan Xiao ◽

...

Keyword(s):

Species Diversity ◽

Liquid Nitrogen ◽

Dna Extraction ◽

Extraction Efficiency ◽

Bacterial Colonization ◽

Care Hospital ◽

Bacterial Dna ◽

Freeze Thaw ◽

Low Efficiency ◽

Bacterial Dna Extraction

Although the presence of live microbes in utero remains under debate, newborn gastrointestinal bacteria are undoubtedly important to infant health. Measuring bacteria in meconium is an ideal strategy to understand this issue; however, the low efficiency of bacterial DNA extraction from meconium has limited its utilization. This study aims to improve the efficiency of bacterial DNA extraction from meconium, which generally has low levels of microflora but high levels of PCR inhibitors in the viscous matrix. The research was approved by the ethical committee of the Xiamen Maternity and Child Health Care Hospital, Xiamen, China. All the mothers delivered naturally, and their newborns were healthy. Meconium samples passed by the newborns within 24 h were collected. Each sample was scraped off of a sterile diaper, transferred to a 5-ml sterile tube, and stored at −80°C. For the assay, a freeze-thawing sample preparation protocol was designed, in which a meconium-InhibitEX buffer mixture was intentionally frozen 1–3 times at −20°C, −80°C, and (or) in liquid nitrogen. Then, DNA was extracted using a commercial kit and sequenced by 16S rDNA to verify the enhanced bacterial DNA extraction efficiency. Ultimately, we observed the following: (1) About 30 mg lyophilized meconium was the optimal amount for DNA extraction. (2) Freezing treatment for 6 h improved DNA extraction at −20°C. (3) DNA extraction efficiency was significantly higher with the immediate thaw strategy than with gradient thawing at −20°C, −80°C, and in liquid nitrogen. (4) Among the conditions of −20°C, −80°C, and liquid nitrogen, −20°C was the best freezing condition for both improving DNA extraction efficiency and preserving microbial species diversity in meconium, while liquid nitrogen was the worst condition. (5) Three freeze-thaw cycles could markedly enhance DNA extraction efficiency and preserve the species diversity of meconium microflora. We developed a feasible freeze-thaw pretreatment protocol to improve the extraction of microbial DNA from meconium, which may be beneficial for newborn bacterial colonization studies.

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70 REFREEZING POST-THAWED GOAT SEMEN

Reproduction Fertility and Development ◽

10.1071/rdv23n1ab70 ◽

2011 ◽

Vol 23 (1) ◽

pp. 140

Author(s):

D. B. Carwell ◽

B. R. Scott ◽

G. T. Gentry ◽

K. R. Bondioli ◽

R. A. Godke

Keyword(s):

Liquid Nitrogen ◽

Sperm Morphology ◽

Membrane Integrity ◽

Egg Yolk ◽

Slow Cool ◽

Semen Parameters ◽

Slow Cooling ◽

Freeze Thaw ◽

Thaw Cycle ◽

Frozen Semen

The ability to successfully refreeze caprine sperm could provide a means of salvaging semen that was mistakenly thawed. The objective of this study was to compare treatment post-thaw semen parameters of twice-frozen caprine semen. Frozen semen from six mature Boer bucks (range in age from 2 to 6 years) was utilised for this experiment. Semen from each buck was extended in an egg yolk-based extender and packaged in 0.5-mL plastic straws before freezing and stored in liquid nitrogen. Three units of frozen semen from each buck was randomly allotted to each of four treatments as follows: (A) thaw and evaluate (control), (B) thaw, then plunge into liquid nitrogen, thaw, and evaluate, (C) thaw, incubate for 3 min at 37°C, slow cool and freeze, thaw, and evaluate, and (D) thaw, incubate for 5 min at 37°C, slow cool and freeze, thaw, and evaluate. Post-thaw parameters included total motility (TM), progressive motility (PM), membrane integrity (MI), and sperm abnormalities (AB). To obtain MI and AB, samples were stained with an eosin-nigrosin stain. A computerized programmable freezer was used to refreeze semen samples in treatment (Trt) C and Trt D. During the slow cooling portion of the protocol, samples were allowed to equilibrate at 38°C, then cooled to 4°C at a rate of 0.30°C min–1, and then held for 5 min. Samples were then cooled to –8°C at a rate of 15°C min–1, seeded, and cooled to –10°C at 15°C min–1, samples were then ramped to –80°C at 30°C min–1 before plunging into liquid nitrogen. Results indicate that post-thaw TM was significantly greater for Trt A (60%) when compared with Trt B, C, and D (0.05, 35, and 39%, respectively). Mean TM were not different between Trt C (35%) and Trt D (39%) but were greater than that for Trt B (0.05%). The PM for post-thaw semen in Trt A was also significantly greater (P < 0.05) when compared with that for Trt B and C (0.05 and 25%); however, no difference was found for mean PM for Trt A (47%) and Trt D (30%), nor were differences found between Trt C (25%) or Trt D (30%). Membrane integrity was higher in Trt A (27%) when compared to Trt B (2.2%). No differences in membrane integrity where found between Trt A, C, and D (27, 13, and 14%, respectively). Additionally, no differences were found between Trt B, C, and D for membrane integrity. Sperm morphology were not different were found with across all treatment groups. These results (i.e. Trt C and D) indicate that semen from mature Boer bucks can undergo a second freeze thaw cycle and still retain motility without dramatically affecting sperm morphology and membrane integrity. These findings indicate that directly plunging recently thawed semen back into liquid nitrogen should not be used for artificial insemination.

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