47 COMPARISON BETWEEN CRYOLOOP AND OPEN PULLED STRAW VITRIFICATION METHODS FOR BOS INDICUS BLASTOCYSTS

2014 ◽  
Vol 26 (1) ◽  
pp. 137 ◽  
Author(s):  
E. Herrera-Puerta ◽  
N. Chavarria ◽  
R. Urrego ◽  
N. Rodriguez-Osorio
Keyword(s):  
Large Scale ◽  
High Efficiency ◽  
Mammalian Species ◽  
Bos Indicus ◽  
Commercial Application ◽  
Hatching Rate ◽  
Cooling Rates ◽  
Wide Range ◽  
Significant Difference ◽  
Hatching Rates

A major obstacle of large-scale commercial application of bovine in vitro fertilization is the lack of a suitable cryopreservation method for supernumerary embryos produced. The traditional slow-freezing method has proven to be effective for embryos of a wide range of mammalian species; however, the formation of intracellular ice is still a challenge and the efficiency needs to be improved. Over the past decade, several advances have taken place in vitrification technologies, such that it can provide high efficiency with better pregnancy outcome due to its high cooling rates and the lack of crystals formed inside the cells. Most vitrification methods have been evaluated in Bos taurus cattle but more still remains to be investigated in Bos indicus races predominant in the tropics. There are several vitrification protocols and holders, including CryoLoop, open pulled straw (OPS), MS Grids, and Cryotop, among others. The CryoLoop method uses a nylon loop attached to a metal Cryovial lid were blastocysts are placed on an equilibration solution film. CryoLoop cooling rates are approximately 20.000°C min–1 and have shown very good results in humans. The OPS is a well-known support for bovine blastocysts; the embryos are taken by capillarity into the OPS and use a 1- to 2-μL drop of final equilibration solution. Cooling rates using this method are approximately 2.000°C min–1. The aim of this work was to prove CryoLoop and OPS vitrification methods in Bos indicus blastocyst and compare re-expansion and hatching rates 24 h after warming. Ovaries were collected from a local slaughterhouse and cumulus-oocyte complexes (COC) were treated for the standard IVF method. A total of 60 blastocysts were vitrified in CryoLoops and 68 blastocysts in OPS (within 4 repeats). For CryoLoops, groups of 2 blastocysts were placed in a solution of 7.5% ethylene glycol (EG) and 7.5% dimethyl sulfoxide (DMSO) for 3 min, and then were placed in a solution of 15% EG, 15% DMSO, 10 mg mL–1 of Ficoll 70, and 0.65 M sucrose for 20 s, and rapidly were put into the nylon loop and taken to the LN. For OPS, groups of 2 to 3 blastocysts were placed in a solution of 10% EG and 10% DMSO for 1 min, and then were placed in a solution of 20% EG and 20% DMSO for 20 s, and rapidly were taken by capillarity into the OPS and taken to the LN. Thawing was the same for both treatments; vitrified blastocysts were taken out from the LN and rapidly put into a solution of 0.3 M sucrose for 2 min and then put into a solution of 0.2 M sucrose for 3 min, were washed twice in TCM199 supplemented with 10% FCS, and cultured for 24 h in CR1aa media. Data were analysed using the R language. Media comparison for proportions was done using a chi-squared test. No significant difference was observed in re-expansion or hatching rates between CryoLoop and OPS supports (P = 0.01 for both); however, the CryoLoop method showed more efficiency than OPS in re-expansion rate (65 v. 44.4%, respectively) and hatching rate (30.8 v. 20%, respectively). In all cases, the CryoLoop method showed much better outcomes. The results indicate that vitrification in CryoLoops is a suitable method for cryopreservation of Bos indicus blastocysts.

A Comparison of Double-Isotope Derivative and Radioimmunological Estimation of Plasma Aldosterone Concentration in Man

1973 ◽  
Vol 45 (3) ◽  
pp. 411-415 ◽  
Author(s):  
R. Fraser ◽  
Sheena Guest ◽  
Jessie Young
Keyword(s):  
Large Scale ◽  
Plasma Aldosterone ◽  
Plasma Aldosterone Concentration ◽  
Plasma Pool ◽  
Wide Range ◽  
Significant Difference ◽  
Derivative Method ◽  
Scale Population ◽  
Suitable Technique ◽  
Double Isotope

1. Two techniques for estimating plasma aldosterone concentration are compared by means of repeated assays of a plasma pool and also by analysis of a wide range of plasma samples. 2. No significant difference was found in the results obtained by the methods. Radioimmunoassay required only one tenth of the volume of plasma needed for the double-isotope derivative method. 3. Its rapidity and relative inexpensiveness makes radioimmunoassay at present the most suitable technique for large-scale population screening.

scholarly journals Seasonal dynamics of Daphnia laevisBirge, 1878 ephippia in a tropical lake with a description of a new methodology for in situ evaluation

2014 ◽  
Vol 74 (3) ◽  
pp. 642-648 ◽  
Author(s):  
LPM Brandão ◽  
DGF Pujoni ◽  
PM Maia-Barbosa
Keyword(s):  
Water Column ◽  
Seasonal Dynamics ◽  
Thermal Stratification ◽  
Core Sample ◽  
Hatching Rate ◽  
The Core ◽  
Significant Difference ◽  
Chi Squared ◽  
Hatching Rates

The effect of dormancy in zooplankton populations is still unknown, largely because of the lack of methods to estimate hatching and production of the dormant stages. This study aimed to compare the production and hatching rates of ephippia of Daphnia laevis between thermal stratification and mixing periods in Jacaré Lake (Middle Rio Doce, Minas Gerais, Brazil). For this, we collected ephippia on the sediment with core sampler and we created a device called the “Ephippial Collector”. There was a significant difference in ephippia hatching in situ between stratification and mixing periods (Pearson's Chi-squared test p <0.001), being higher in the second one. Significant differences in the hatching rates between periods was observed in the laboratory only for ephippia collected with Ephippial Collectors (Pearson's Chi-squared test p <0.001), being higher during the mixing period (∼8%). The core sample allows the collection of a certain fraction of the sediment that may contain a mixture of ephippia produced in different periods, i.e., may contain old and not viable ephippia, which masks the hatching rate. Thus, seasonality in hatching rates of ephippia was reported only by Ephippial Collectors. The higher hatching rate observed during the mixing period in the lake suggests that individuals hatched from ephippia may contribute to the increase in the population of D. laevis in the water column at this time.

Development and population dynamics of Steinernema yirgalemense (Rhabditida: Steinernematidae) and growth characteristics of its associated Xenorhabdusindica symbiont in liquid culture

2015 ◽  
Vol 90 (3) ◽  
pp. 364-371 ◽  
Author(s):  
T. Ferreira ◽  
M.F. Addison ◽  
A.P. Malan
Keyword(s):  
Population Density ◽  
Liquid Culture ◽  
Commercial Application ◽  
Adult Density ◽  
Developmental Phase ◽  
Male Density ◽  
Wide Range ◽  
Significant Difference

AbstractEntomopathogenic nematodes have become a valuable addition to the range of biological control agents available for insect control. An endemic nematode, Steinernemayirgalemense, has been found to be effective against a wide range of key insect pests. The next step would be the mass production this nematode for commercial application. This requires the establishment of monoxenic cultures of both the nematode and the symbiotic bacterium Xenorhabdus indica. First-stage juveniles of S. yirgalemense were obtained from eggs, while X. indica was isolated from nematode-infected wax moth larvae. The population density of the various life stages of S. yirgalemense during the developmental phase in liquid culture was determined. The recovery of infective juveniles (IJs) to the third-stage feeding juveniles, was 67 ± 10%, reaching a maximum population density of 75,000 IJs ml− 1 on day 13 after inoculation. Adult density increased after 8 days, with the maximum female density being 4600 ml− 1 on day 15, whereas the maximum male density was 4300 ml− 1 on day 12. Growth curves for X. indica showed that the exponential phase was reached 15 h after inoculation to the liquid medium. The stationary phase was reached after 42 h, with an average of 51 × 107 colony-forming units ml− 1. Virulence tests showed a significant difference in insect mortality between in vitro- and in vivo-produced nematodes. The success obtained with the production of S. yirgalemense in liquid culture can serve as the first step in the optimizing and upscaling of the commercial production of nematodes in fermenters.

scholarly journals Performance test on a 5kW SOFC system under high fuel utility with practical syngas feeding

2020 ◽  
Author(s):  
ming xu ◽  
Hanlin Wang ◽  
Mingxian Liu ◽  
Jianning Zhao ◽  
Yuqiong Zhang ◽  
...  
Keyword(s):  
Power Generation ◽  
Fuel Cell ◽  
Large Scale ◽  
Performance Test ◽  
High Efficiency ◽  
Green Energy ◽  
Commercial Application ◽  
Fuel Gas ◽  
Term Operation

Abstract With increasing demand of green energy supply with high efficiency and low CO2 emission, Solid oxide fuel cell (SOFC) has been intensively developed in recent years. And the integration of gasification with fuel cell (IGFC) shows potential in large scale power generation to further increase the system efficiency. Reliable design of multi-stacks for large system and long term stability of stacks with practical fuel gas from industrial equipment are the key for commercial application of IGFC. In this work, a test rig of 5kW SOFC system was fabricated using practical syngas from industrial gasifiers as fuel and long term test under high fuel utility was conducted to investigate the system performance. The results show that the maximum steady output power of system is 5700W for hydrogen case and 5660W for syngas case, and the maximum steady electrical efficiency is 61.24% while the fuel utility efficiency is 89.25%. The test lasted for more than 500h as the fuel utility efficiency was larger than 83%. The performances of each stack tower are almost identical at both initial stage and after long term operation. After 500h operation, the performances of stack towers just slight decrease under lower current and almost not change under higher current. Therefore, the results illustrate that the reliability of multi-stacks design and the prospect of SOFC power generation system for further enlarging its application in a MWth demonstration.

scholarly journals Research on the Principle and Cooperative Processing Method of MRS Multisystem Joint Detection

Sensors ◽  
2021 ◽  
Vol 21 (20) ◽  
pp. 6725
Author(s):  
Cong Li ◽  
Zhaofa Zeng ◽  
Zhuo Wang ◽  
Xiaofeng Yi
Keyword(s):  
Large Scale ◽  
High Efficiency ◽  
Joint Detection ◽  
Multiple Systems ◽  
Work Area ◽  
Magnetic Resonance Sounding ◽  
Wide Range ◽  
Working Together ◽  
Working Distance ◽  
Measurement Efficiency

Magnetic resonance sounding (MRS) technology is the only geophysical means to directly and quantitatively detect groundwater and has achieved good results in hydrogeological prospecting applications. In recent years, researchers have conducted considerable research on the efficiency of a single instrument, yielding certain results. However, the overall work efficiency of this method has not been effectively determined in its application to a large-scale survey. Hence, we propose both a joint detection method for MRS that determines the minimum working distance when multiple systems operate simultaneously and a collaborative measurement method of dual systems operating simultaneously in a fixed range of work areas. The cooperative working mode of the instruments is tested in the detection area, and the working mode proposed in this paper is shown to effectively avoid measurement interference between systems. Compared with the working mode of a single set of instruments, the measurement efficiency is more than doubled. Through this research, the feasibility of multiple MRS instruments working together in the same work area is verified, which provides effective technical support for the rapid and high-efficiency utilization of MRS over a wide range of measurement areas.

ORGANOMETAL HALIDE PEROVSKITE PHOTOVOLTAICS: A DIAMOND IN THE ROUGH

NANO ◽  
2014 ◽  
Vol 09 (05) ◽  
pp. 1440002 ◽  
Author(s):  
MICHAEL GRÄTZEL ◽  
NAM-GYU PARK
Keyword(s):  
Thermal Stability ◽  
Large Scale ◽  
High Efficiency ◽  
Power Conversion ◽  
Perovskite Solar Cell ◽  
Commercial Application ◽  
The Sun ◽  
Metal Halide Perovskite ◽  
Organometal Halide Perovskite ◽  
Halide Perovskite

The sun finds a diamond in the rough, which is the organo-metal halide perovskite. Thanks to exceptional optoelectronic characteristics, solar cells employing perovskite demonstrated first a power conversion efficiency (PCE) of 9.7% in the middle of 2012, which rose steeply to an amazing 16% at the end of 2013. Perovskite-based photovoltaics have several advantages over conventional semiconductor p-n junction devices because high efficiency can be achieved from sub-micrometer-thick very cheap perovskite layers that can be formed by solution processing at temperatures below 150°C, rendering the perovskite solar cell versatile in its application. If photo- and thermal stability as well as tolerance to humidity can be achieved, commercial application on the large scale appear to be feasible.

scholarly journals 86COMPARISON OF TWO VITRIFICATION PROTOCOLS FOR CROSSBRED BOS INDICUS×BOS TAURUS IN VITRO-PRODUCED EMBRYOS

2004 ◽  
Vol 16 (2) ◽  
pp. 164 ◽  
Author(s):  
L.S.A. Camargo ◽  
R.S. Oliveira ◽  
J.H.M. Viana ◽  
W.F. Sá ◽  
A.M. Ferreira ◽  
...  
Keyword(s):  
Ethylene Glycol ◽  
Liquid Nitrogen ◽  
Bos Indicus ◽  
Cumulus Cells ◽  
Dairy Herds ◽  
Hatching Rate ◽  
Humid Atmosphere ◽  
Significant Difference ◽  
Vitrification Solution

Dairy herds in tropical countries are often maintained as crossbred B. indicus×B. taurus hybrids to take advantage of heterosis, such as resistance to heat stress. Creating crossbred B. indicus×B. taurus embryos by in vitro methods may offer a means of rapidly improving tropical dairy herds, especially if the embryos can be cryopreserved. The aim of this study was to compare the viability of in vitro-produced crossbred B. indicus×B. taurus embryos (1/2, 3/4) using two vitrification solutions and equilibration/dilution temperatures. Cumulus-oocyte complexes were aspirated from purebred B. indicus and crossbred (B. indicus×B. taurus hybrid) ovaries, matured in vitro, and fertilized with spermatozoa collected from a Holstein bull. Presumptive zygotes were co-cultured in CR2aa medium with cumulus cells, in a humid atmosphere of 5% CO2-air at 38.8°C. On day 7 of co-culture, embryos were assessed and classified as good or excellent, and those at the appropriate developmental stage were vitrified using one of two vitrification solutions, a mixture of either glycerol/ethylene glycol (GE) or dimethylsulphoxide/ethylene glycol (DE). Embryos (n=34) assigned to GE vitrification were equilibrated in a medium of PBS+20% FCS (HM1) containing 10% v/v G for 5min, followed by 10% v/v G+20% v/v E for 5min., and then transferred to a vitrification solution of 25% v/v G+25% v/v E in HM1 for 30s. The embryos were immediately aspirated into an Open Pulled Straw (OPS) and plunged into liquid nitrogen. Embryos vitrified in GE were warmed by immersing the OPS in HM1 containing 1M sucrose for 1min (37°C), then stepwise diluted in fresh HM1 containing 1M, 0.5M, and 0.25M sucrose for 5min; and finally washed in HM1. Stepwise equilibration and dilution of GE embryos was at 20°C. Embryos (n=43) assigned to DE vitrification were equilibrated in a medium of PBS+5% FCS (HM2) containing 10% v/v D+10% v/v E for 1min, and then transferred to a vitrification solution of 20% v/v D+20% v/v E in HM2 for 30s. The embryos were immediately aspirated into an Open Pulled Straw (OPS) and plunged into liquid nitrogen. Embryos vitrified in DE were warmed by immersing the OPS in HM2 containing 0.25M sucrose for 1min (39°C), then stepwise diluted in fresh HM2 containing 0.25M and 0.15M sucrose for 5min, and finally washed in HM2. Stepwise equilibration and dilution of DE embryos was at 39°C. Diluted embryos from both groups and untreated control embryos (n=49) were cultured in TCM-199 with monolayer granulosa cells for 72h in conditions described above. Blastocyst re-expansion and hatching was assessed and analyzed by chi-square test. Overall, 67% of the thawed embryos were expanded blastocysts (remainder were blastocysts) and 56% were excellent quality (remainder were good). No significant difference (P&gt;0.05) was found between the rates of blastocyst re-expansion and hatching for the GE and DE vitrification procedures (respectively, 59 and 79%, and 41 and 58%). However the hatching rate of control embryos (77%) was significantly higher than that of vitrified embryos (P&lt;0.05). These results indicate that both vitrification procedures are promising for the cryopreservation of crossbred B. indicus×B. taurus in vitro-produced embryos. Supported by CNPq.

scholarly journals Mass production of 2D materials by intermediate-assisted grinding exfoliation

2019 ◽  
Vol 7 (2) ◽  
pp. 324-332 ◽  
Author(s):  
Chi Zhang ◽  
Junyang Tan ◽  
Yikun Pan ◽  
Xingke Cai ◽  
Xiaolong Zou ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Production Rate ◽  
Large Scale ◽  
High Efficiency ◽  
2D Materials ◽  
Commercial Application ◽  
Image Method ◽  
Scale Production ◽  
Micro Particles ◽  
High Production Rate

Abstract The scalable and high-efficiency production of 2D materials is a prerequisite to their commercial use. Currently, only graphene and graphene oxide can be produced on a ton scale, and the inability to produce other 2D materials on such a large scale hinders their technological applications. Here we report a grinding exfoliation method that uses micro-particles as force intermediates to resolve applied compressive forces into a multitude of small shear forces, inducing the highly efficient exfoliation of layer materials. The method, referred to as intermediate-assisted grinding exfoliation (iMAGE), can be used for the large-scale production of many 2D materials. As an example, we have exfoliated bulk h-BN into 2D h-BN with large flake sizes, high quality and structural integrity, with a high exfoliation yield of 67%, a high production rate of 0.3 g h−1 and a low energy consumption of 3.01 × 106 J g−1. The production rate and energy consumption are one to two orders of magnitude better than previous results. Besides h-BN, this iMAGE technology has been used to exfoliate various layer materials such as graphite, black phosphorus, transition metal dichalcogenides, and metal oxides, proving its universality. Molybdenite concentrate, a natural low-cost and abundant mineral, was used as a demo for the large-scale exfoliation production of 2D MoS2 flakes. Our work indicates the huge potential of the iMAGE method to produce large amounts of various 2D materials, which paves the way for their commercial application.

scholarly journals Efficient exascale discretizations: High-order finite element methods

2021 ◽  
pp. 109434202110208
Author(s):  
Tzanio Kolev ◽  
Paul Fischer ◽  
Misun Min ◽  
Jack Dongarra ◽  
Jed Brown ◽  
...  
Keyword(s):  
Finite Element ◽  
Research And Development ◽  
Finite Element Methods ◽  
Large Scale ◽  
High Efficiency ◽  
High Order ◽  
Computational Time ◽  
Data Movement ◽  
Wide Range ◽  
Matrix Free

Efficient exploitation of exascale architectures requires rethinking of the numerical algorithms used in many large-scale applications. These architectures favor algorithms that expose ultra fine-grain parallelism and maximize the ratio of floating point operations to energy intensive data movement. One of the few viable approaches to achieve high efficiency in the area of PDE discretizations on unstructured grids is to use matrix-free/partially assembled high-order finite element methods, since these methods can increase the accuracy and/or lower the computational time due to reduced data motion. In this paper we provide an overview of the research and development activities in the Center for Efficient Exascale Discretizations (CEED), a co-design center in the Exascale Computing Project that is focused on the development of next-generation discretization software and algorithms to enable a wide range of finite element applications to run efficiently on future hardware. CEED is a research partnership involving more than 30 computational scientists from two US national labs and five universities, including members of the Nek5000, MFEM, MAGMA and PETSc projects. We discuss the CEED co-design activities based on targeted benchmarks, miniapps and discretization libraries and our work on performance optimizations for large-scale GPU architectures. We also provide a broad overview of research and development activities in areas such as unstructured adaptive mesh refinement algorithms, matrix-free linear solvers, high-order data visualization, and list examples of collaborations with several ECP and external applications.

scholarly journals Performance Test on a 5kw Sofc System Under High Fuel Utility With Practical Syngas Feeding

2020 ◽  
Author(s):  
ming xu ◽  
Hanlin Wang ◽  
Mingxian Liu ◽  
Jianning Zhao ◽  
Yuqiong Zhang ◽  
...  
Keyword(s):  
Power Generation ◽  
Fuel Cell ◽  
Large Scale ◽  
Performance Test ◽  
High Efficiency ◽  
Green Energy ◽  
Commercial Application ◽  
Fuel Gas ◽  
Term Operation

Abstract With increasing demand of green energy supply with high efficiency and low CO2 emission, Solid oxide fuel cell (SOFC) has been intensively developed in recent years. And the integration of gasification with fuel cell (IGFC) shows potential in large scale power generation to further increase the system efficiency. Reliable design of multi-stacks for large system and long term stability of stacks with practical fuel gas from industrial equipment are the key for commercial application of IGFC. In this work, a test rig of 5kW SOFC system was fabricated using practical syngas from industrial gasifiers as fuel and long term test under high fuel utility was conducted to investigate the system performance. The results show that the maximum steady output power of system is 5700W for hydrogen case and 5660W for syngas case, and the maximum steady electrical efficiency is 61.24% while the fuel utility efficiency is 89.25%. The test lasted for more than 500h as the fuel utility efficiency was larger than 83%. The performances of each stack tower are almost identical at both initial stage and after long term operation. After 500h operation, the performances of stack towers just slight decrease under lower current and almost not change under higher current. Therefore, the results illustrate that the reliability of multi-stacks design and the prospect of SOFC power generation system for further enlarging its application in a MWth demonstration.

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