Some Interesting Thermodynamics of the Thermos Flask

The transportation of bovine ovaries would allow the shipment of oocytes for research purposes after the slaughter of valuable cows. The objective of this study was to investigate the effect of long-term transportation of ovaries on the development of in vitro-produced bovine embryos. After collection of the ovaries from a slaughterhouse, they were placed inside a thermos flask and transported to the laboratory. The thermos flask was covered with a freezer pack in a foam polystyrene box. The transportation time was 17–18 h, and the temperature of the thermos flask changed from 20°C to 28°C (average 23.8°C) during the transportation. Cumulus–oocyte complexes (COCs) were collected by the aspiration of follicles with a diameter of 2–6 mm. The COCs were matured for 20 h in IVMD101 (RIFP: Research Institute for the Functional Peptides, Yamagata, Japan) containing DM199 supplemented with 5.56 mM glucose, 0.91 mM pyruvate, 5 mM taurine, 5 mM selenium, 5 mM HEPES, and 10 µg/mL gentamicin at 38.5°C under an atmosphere of 5% CO2 in air (Hoshi 2003 Theriogenology 59, 675–685). The matured COCs were inseminated with 5 × 106 sperm/mL in IVF100 (RIFP) medium comprising a modified BO medium supplemented with 1.25 mM sodium pyruvate, 0.5 mM cysteine, 5 mg/mL BSA, 7.5 µg/mL sodium heparin, 5 mM caffeine, and 10 µg/mL gentamicin. After 6 h of gamete co-culture, the presumed zygotes were cultured in IVD101 (RIFP) medium comprising DM199, 2.48 mM lactate, 0.27 mM pyruvate, and 2.22 mM of glucose for 9 days at 38.5°C under an atmosphere of 5% CO2, 5% O2, and 90% N2 in air. As controls, bovine ovaries were transported to the laboratory within 1–1.5 h. Embryo development was evaluated based on the cleavage rate, blastocyst rate, and total number of cells on Days 7–9 after in vitro fertilization. The experiment was replicated five times, and data were analyzed by chi-square test and ANOVA. Results are presented in Table 1. There were no differences in the cleavage rate between the treatments. The blastocyst rate and the number of cells in the blastocyst after long-term transportation of ovaries were significantly lower than those in the controls. These results suggest that the long-term transportation of bovine ovaries does not affect on the cleavage; however, the blastocyst rate and the quality of blastocysts may be affected. Therefore, additional experiments are required to determine suitable conditions for long-term transportation of bovine ovaries. Table 1. Effect of long-term transportation of ovaries on the development of bovine IVM/IVF embryos

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148 Effect of concentration of methionine in maturation and culture medium on cleavage rate of oocytes from alpaca (Lama pacos)

Reproduction Fertility and Development ◽

10.1071/rdv31n1ab148 ◽

2019 ◽

Vol 31 (1) ◽

pp. 199

Author(s):

M. L. Uchuari ◽

M. Artica ◽

J. C. Villanueva ◽

W. F. Huanca ◽

W. Huanca

Keyword(s):

In Vitro Maturation ◽

Culture Medium ◽

Egg Yolk ◽

Cumulus Cells ◽

Cleavage Rate ◽

Sodium Pyruvate ◽

Maturation Medium ◽

Thermos Flask ◽

Lama Pacos

Maturation time of oocytes from alpacas is around 38 to 40h (Huanca et al. 2009) that would induce an increase in reactive oxygen species during in vitro maturation and IVF and cause cytotoxic damage to gametes. The objective of this study was to determine the optimal concentration of methionine during in vitro maturation on cleavage rate of alpacas oocytes following IVF. Cumulus-oocyte complexes were collected from slaughterhouse ovaries and transported in a thermos flask containing a saline solution 0.9% and antibiotic, antimycotic at 35°C. Cumulus-oocyte complexes were aspirated from follicles >2mm and evaluated with a stereomicroscope for selection. Only cumulus-oocyte complexes with a homogeneous cytoplasm and with 2 or more layers of cumulus cells were selected to be cultured in maturation medium TCM-199 supplemented with 10% FCS (v:v) plus 0.5μg mL−1 FSH, 10μg mL−1 hCG, 0.2mM sodium pyruvate, 50μg mL−1gentamycin and 1μg mL−1 oestradiol under mineral oil by 38h. Testes of mature males were collected from a slaughterhouse and transported to the laboratory. Caudal epididymide was isolated, and fluid, rich in spermatozoa, was aspirated in syringes containing 2mL of Tris-fructose-egg yolk extender. Motile spermatozoa were obtained by centrifugation at 700×g in a Percoll discontinuous gradient (22.5: 45.0%) for 10min. The supernatant was removed by aspiration, and the pellet was resuspended in TL stock and centrifuged again at 700×g for 5min. Spermatozoa and oocytes were co-incubated by 18h at 39°C with 5% CO2. Presumptive zygotes were culture in KSOMaa medium and evaluated at 72h. The treatments include 0, 14 and 21 μM of methionine in maturation and culture medium. Data were analysed by ANOVA, and results are presented in Table 1. The results suggest that addition of methionine in maturation and culture medium improve the cleavage rate in oocytes from alpacas. Table 1.Cleavage rate (%) following in vitro maturation at different concentrations of methionine Proyect 405-PNICP-PIAP-2014, INNOVATE-PERU, is acknowledged.

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The Solar Kettle-Thermos Flask (SK-TF) and Aolar Vacuum Tube Oven

Proceedings of ISES World Congress 2007 (Vol. I – Vol. V) ◽

10.1007/978-3-540-75997-3_395 ◽

2008 ◽

pp. 1939-1946

Author(s):

Alex Kee Koo Yak

Keyword(s):

Vacuum Tube ◽

Thermos Flask

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Maintaining Plasmodium falciparum gametocyte infectivity during blood collection and transport for mosquito feeding assays in the field

Malaria Journal ◽

10.1186/s12936-021-03725-y ◽

2021 ◽

Vol 20 (1) ◽

Author(s):

Harouna M. Soumare ◽

Wamdaogo Moussa Guelbeogo ◽

Marga van de Vegte-Bolmer ◽

Geert-Jan van Gemert ◽

Zongo Soumanaba ◽

...

Keyword(s):

Plasmodium Falciparum ◽

Burkina Faso ◽

Water Temperature ◽

The Gambia ◽

Short Term ◽

Infected Blood ◽

Membrane Feeding ◽

Thermos Flask ◽

The Impact

Abstract Background Mosquito feeding assays using venous blood are commonly used for evaluating the transmission potential of malaria infected individuals. To improve the accuracy of these assays, care must be taken to prevent premature activation or inactivation of gametocytes before they are fed to mosquitoes. This can be challenging in the field where infected individuals and insectary facilities are sometimes very far apart. In this study, a simple, reliable, field applicable method is presented for storage and transport of gametocyte infected blood using a thermos flask. Methods The optimal storage conditions for maintaining the transmissibility of gametocytes were determined initially using cultured Plasmodium falciparum gametocytes in standard membrane feeding assays (SMFAs). The impact of both the internal thermos water temperature (35.5 to 37.8 °C), and the external environmental temperature (room temperature to 42 °C) during long-term (4 h) storage, and the impact of short-term (15 min) temperature changes (room temp to 40 °C) during membrane feeding assays was assessed. The optimal conditions were then evaluated in direct membrane feeding assays (DMFAs) in Burkina Faso and The Gambia where blood from naturally-infected gametocyte carriers was offered to mosquitoes immediately and after storage in thermos flasks. Results Using cultured gametocytes in SMFAs it was determined that an internal thermos water temperature of 35.5 °C and storage of the thermos flask between RT (~ 21.3 °C) and 32 °C was optimal for maintaining transmissibility of gametocytes for 4 h. Short-term storage of the gametocyte infected blood for 15 min at temperatures up to 40 °C (range: RT, 30 °C, 38 °C and 40 °C) did not negatively affect gametocyte infectivity. Using samples from natural gametocyte carriers (47 from Burkina Faso and 16 from The Gambia), the prevalence of infected mosquitoes and the intensity of oocyst infection was maintained when gametocyte infected blood was stored in a thermos flask in water at 35.5 °C for up to 4 h. Conclusions This study determines the optimal long-term (4 h) storage temperature for gametocyte infected blood and the external environment temperature range within which gametocyte infectivity is unaffected. This will improve the accuracy, reproducibility, and utility of DMFAs in the field, and permit reliable comparative assessments of malaria transmission epidemiology in different settings.

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Maintaining Plasmodium Falciparum Gametocyte Infectivity During Blood Collection and Transport for Mosquito Feeding Assays in the Field

10.21203/rs.3.rs-148299/v1 ◽

2021 ◽

Author(s):

Harouna M. Soumare ◽

Wamdaogo Moussa Guelbeogo ◽

Marga van-de Vegte-Bolmer ◽

Geert-Jan van Gemert ◽

Zongo Soumanaba Soumanaba ◽

...

Keyword(s):

Plasmodium Falciparum ◽

Burkina Faso ◽

Water Temperature ◽

The Gambia ◽

Short Term ◽

Infected Blood ◽

Membrane Feeding ◽

Thermos Flask ◽

The Impact

Abstract BackgroundMosquito feeding assays using venous blood are commonly used for evaluating the transmission potential of malaria infected individuals. To improve the accuracy of these assays, care must be taken to prevent premature activation or inactivation of gametocytes before they are fed to mosquitoes. This can be challenging in the field where infected individuals and insectary facilities are sometimes very far apart. In this study, a simple, reliable, field applicable method is presented for storage and transport of gametocyte infected blood using a thermos flask. MethodsThe optimal storage conditions for maintaining the transmissibility of gametocytes were determined initially using cultured Plasmodium falciparum gametocytes in standard membrane feeding assays (SMFAs). The impact of both the internal thermos water temperature (35.5 – 37.8°C), and the external environmental temperature (room temp – 42°C) during long-term (4hr) storage, and the impact of short-term temperature changes (room temp – 40°C) during membrane feeding assays was assessed. The optimal conditions were then evaluated in direct membrane feeding assays (DMFAs) in Burkina Faso and The Gambia where blood from naturally infected gametocyte carriers was offered to mosquitoes immediately and after storage in thermos flasks. ResultsUsing cultured gametocytes in SMFAs it was determined that an internal thermos water temperature of 35.5°C and storage of the thermos flask between RT (~21.3°C) and 32°C was optimal for maintaining transmissibility of gametocytes for 4 hours. Short-term storage of the gametocyte infected blood at temperatures up to 38°C (range: RT, 30°C and 38°C) did not have a negative effect on gametocyte infectivity. Using samples from natural gametocyte carriers (47 from Burkina Faso and 16 from The Gambia), the prevalence of infected mosquitoes and the intensity of oocyst infection was maintained when gametocyte infected blood was stored in a thermos flask in water at 35.5°C for up to 4 hours.ConclusionsThis study determines the optimal long-term (4 hours) storage temperature for gametocyte infected blood and the external environment temperature range within which gametocyte infectivity is unaffected. This will improve the accuracy, reproducibility, and utility of DMFAs in the field, and permit reliable comparative assessments of malaria transmission epidemiology in different settings.

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157 FIRST IN VITRO EMBRYO PRODUCTION IN ALPACAS (LAMA PACOS)

Reproduction Fertility and Development ◽

10.1071/rdv21n1ab157 ◽

2009 ◽

Vol 21 (1) ◽

pp. 177 ◽

Cited By ~ 6

Author(s):

G. Gamarra ◽

E. Huaman ◽

S. León ◽

M. Carpio ◽

E. Alvarado ◽

...

Keyword(s):

South American ◽

Cleavage Rate ◽

Embryo Production ◽

South American Camelids ◽

Nitrogen Vapor ◽

Epidermal Growth ◽

Thermos Flask ◽

In Vitro Embryo Production ◽

Lama Pacos

The objective was to produce alpaca embryos in laboratory due to its potential role for the multiplication of genetically superior animals and for conservation purposes. Ovaries were collected from an alpaca abattoir located in the Central Highlands of Peru and transported in a thermos flask with warm saline and antibiotics to the laboratory located 200 km away on the coast. Alpaca epididymal sperm to be used for fertilization was previously frozen by diluting in a TRIS-Fructose based extender with 10% glycerol and frozen as pellets in liquid nitrogen vapor. From 31 ovaries, 262 cumulus–oocyte complexes (COCs) were collected (mean of 8.5 COCs per ovary) which were matured in TCM-199 supplemented with 10% heat inactivated FCS plus epidermal growth factor (EGF), FSH, LH, estradiol, and cysteamine for 30 h incubation at 38.5°C, 5% CO2 and 90% humidity. The selected oocytes post-maturation were fertilized with the frozen/thawed sperm that was subjected post-thawing to Percoll gradient (90 and 45% Percoll), centrifugation and resuspension in TALP-IVF medium supplemented with 20 μm D-penicillamine, 10 μm hypotaurine, 1 μm epinephrine and 1.1 μg mL–1 of heparin. The oocytes were inseminated with a concentration of 10 × 106 spermatozoa per drop of 100 mL of fertilization medium containing 30 oocytes each and incubated for 24 h at 38.5°C, 5% CO2 and 90% humidity. The presumptive zygotes were transferred to 200 μL drops (30 zygotes per drop) of SOFaa media supplemented with 5% heat-inactivated FCS which was replaced by SOFaa plus 1% heat-inactivated FCS on day 5 after fertilization. The incubation period post-fertilization was up to day 7 at 38.5°C, 5% CO2 and 90% humidity, when the embryos were inspected and graded. The cleavage rate was evaluated at 72 h post-fertilization and embryo development was evaluated on day 5 and 7 post-fertilization. The cleavage rate was 27.1% (71/262) and the percentage of oocytes that reached the stage of morula and blastocyst was 8.0% (21/262). The percentage of blastocyst that hatched when incubated after day 7 was 14.28% (3/21). The in vitro embryo production in alpacas was successful and suggests the possibility for application in intensive reproduction for conservation of South American camelids and for genetic improvement. Research was partially funded by contributions of BIONICHE and SAIS TUPAC AMARU, Junin, Peru.

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Determination of Band Gap Energy of Semiconductor in Homojunction Structure Devices by Using Customized Microcontroller Based Apparatus

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.896.633 ◽

2014 ◽

Vol 896 ◽

pp. 633-637 ◽

Cited By ~ 1

Author(s):

Kuwat Triyana ◽

Surya Ramadhan ◽

Aji Muhammad Iqbal Barata ◽

Chotimah ◽

Sabarman Harsojo

Keyword(s):

Band Gap ◽

Pid Controller ◽

Forward Bias ◽

Band Gap Energy ◽

Proportional Integral Derivative ◽

Gap Energy ◽

Forward Bias Voltage ◽

Current Voltage ◽

Thermos Flask

We have successfully developed a customized apparatus based on microcontroller for simple band gap energy (Eg) measurement of semiconductors in homojunction structure devices. The apparatus consisted of a data acquisition system based on microcontroller AVR ATMega 128 and a thermos flask equipped with temperature controller. It permits recording of current-voltage (I-V) and temperature and subsequently sends data to a computer to enable the computer processing of such data. For samples under tested, we used two types of commercial diode, i.e. Silicon (1N4007) and Germanium (1N60). In this measurement, the voltage across the resistor was used to calculate the current while the voltage across the diode gave the forward bias voltage. The temperature of diode was varied from 5°C to 80°C. During each I-V measurement, the temperature of diode was maintained to be constant by employing a proportional-integral-derivative (PID) controller to the heater. Furthermore, by varying the temperature of diode, we could extract the saturation currents under reverse bias across the diode of each I-V measurement. For the two types of diode, it is found that the Eg of silicon is 1.13 ± 0.03 eV, while that of germanium is 0.71 ± 0.03 eV. This result is closed to the Eg value of each diode indicated in the respective datasheet. Therefore, it suggests for applying this apparatus for measuring Eg of semiconductor in most homojunction structure devices.

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