Electronic synthesis of printed resistor layout for a thermal petri dish incubator

2019 ◽  
Author(s):  
Matthew Pilkington ◽  
Trudi H. Joubert ◽  
Petroné H. Bezuidenhout ◽  
Kevin Land
Keyword(s):  
Petri Dish

The Fine Structure of Rat Granulosa Cell Cultures Correlated with Progestin Secretion

1973 ◽  
Vol 31 ◽  
pp. 552-553
Author(s):  
T. M. Crisp ◽  
F.R. Denys
Keyword(s):  
Fine Structure ◽  
Granulosa Cell ◽  
Cell Cultures ◽  
Single Injection ◽  
Surrounding Medium ◽  
Petri Dish ◽  
Female Rats ◽  
Vaginal Smear ◽  
Immature Female ◽  
Serum Gonadotropin

The purpose of this paper is to present observations on the fine structure of rat granulosa cell cultures grown in the presence of an adenohypophyseal explant and to correlate the morphology of these cells with progestin secretion. Twenty-six day old immature female rats were given a single injection of 5 IU pregnant mares serum gonadotropin (PMS) in order to obtain ovaries with large vesicular follicles. At 66 hrs. post-PMS administration (estrus indicated by vaginal smear cytology), the ovaries were removed and placed in a petri dish containing medium 199 and 100 U penicillin/streptomycin (P/S)/ml. Under a 20X magnification dissecting microscope, some 5-8 vesicular follicles/ovary were punctured and the granulosa cells were expressed into the surrounding medium. The cells were transferred to centrifuge tubes and spun down at 1000 rpm for 5 mins.

Rotary Beveling for In Situ Thin-Section Microscopy of Cell Cultures

1981 ◽  
Vol 39 ◽  
pp. 550-551
Author(s):  
Dean A. Handley ◽  
Jack T. Alexander ◽  
Shu Chien
Keyword(s):  
Cell Growth ◽  
Cell Cultures ◽  
Molecular Interactions ◽  
Convenient Method ◽  
Petri Dish ◽  
Simple Method ◽  
Thin Section Microscopy ◽  
Thin Sectioning ◽  
Organic Fluids

In situ preparation of cell cultures for ultrastructural investigations is a convenient method by which fixation, dehydration and embedment are carried out in the culture petri dish. The in situ method offers the advantage of preserving the native orientation of cell-cell interactions, junctional regions and overlapping configurations. In order to section after embedment, the petri dish is usually separated from the polymerized resin by either differential cryo-contraction or solvation in organic fluids. The remaining resin block must be re-embedded before sectioning. Although removal of the petri dish may not disrupt the native cellular geometry, it does sacrifice what is now recognized as an important characteristic of cell growth: cell-substratum molecular interactions. To preserve the topographic cell-substratum relationship, we developed a simple method of tapered rotary beveling to reduce the petri dish thickness to a dimension suitable for direct thin sectioning.

Unlabeled Antibody Immunocytochemistry Applied to Murine Mammary Tumor Cells

1975 ◽  
Vol 33 ◽  
pp. 390-391
Author(s):  
Wm. J. Arnold ◽  
J. Russo ◽  
H. D. Soule ◽  
M. A. Rich
Keyword(s):  
Horseradish Peroxidase ◽  
Mammary Tumor ◽  
Covalent Binding ◽  
Petri Dish ◽  
Gamma Chain ◽  
Mammary Tumor Virus ◽  
Mammary Tumor Cells ◽  
Murine Mammary Tumor ◽  
Tumor Virus ◽  
Unlabeled Antibody

Our studies of mammary tumor virus have included the application of the unlabeled antibody enzyme method of Sternberger to mammary tumor derived mouse cells in culture and observation with an electron microscope. The method avoids the extravagance of covalent binding of indicator molecules (horseradish peroxidase) with precious antibody locator molecules by relying instead upon specific antibody-antigen linkages. Our reagents included: Primary Antibody, rabbit anti-murine mammary tumor virus (MuMTV) which was antiserum 113 AV-2; Secondary Antibody, goat anti-rabbit IgG gamma chain (Cappel Laboratories); andthe Indicator, rabbit anti-horseradish peroxidase - horseradish peroxidase complex (PAP) (Cappel Labs.). Dilutions and washes were made in 0.05 M Tris 0.15 M saline buffered to pH 7.4. Cell monolayers, after light fixation in glutaraldehyde, were incubated in place by a protocol adapted from Sternberger and Graham and Karnovsky, then embedded by our usual method for monolayers. Reagents were confined to specific areas by neoprene 0-rings (Parker Seal Co.) reducing the amount of reagent needed to 50 microliters, 1/6th of that required to wet a 35 mm petri dish.

A freeze-fracture-etched study of the physarum polycephalum plasma membrane during early formation of the macroplasmodial stage

1993 ◽  
Vol 51 ◽  
pp. 346-347
Author(s):  
Randolph W. Taylor ◽  
Henrie Treadwell
Keyword(s):  
Plasma Membrane ◽  
Life Cycle ◽  
Growth Phase ◽  
Filter Paper ◽  
Physarum Polycephalum ◽  
Freeze Fracture ◽  
Petri Dish ◽  
Wire Screen ◽  
Wide Mouth ◽  
Sterile Filter

The plasma membrane of the Slime Mold, Physarum polycephalum, process unique morphological distinctions at different stages of the life cycle. Investigations of the plasma membrane of P. polycephalum, particularly, the arrangements of the intramembranous particles has provided useful information concerning possible changes occurring in higher organisms. In this report Freeze-fracture-etched techniques were used to investigate 3 hours post-fusion of the macroplasmodia stage of the P. polycephalum plasma membrane.Microplasmodia of Physarum polycephalum (M3C), axenically maintained, were collected in mid-expotential growth phase by centrifugation. Aliquots of microplasmodia were spread in 3 cm circles with a wide mouth pipette onto sterile filter paper which was supported on a wire screen contained in a petri dish. The cells were starved for 2 hrs at 24°C. After starvation, the cells were feed semidefined medium supplemented with hemin and incubated at 24°C. Three hours after incubation, samples were collected randomly from the petri plates, placed in plancettes and frozen with a propane-nitrogen jet freezer.

The influence of different types of milking units on milk quality and safety

2019 ◽  
pp. 118-125
Author(s):  
A. Vovkohon ◽  
V. Nadtochiy ◽  
G. Kalinina ◽  
O. Hrebelnyk ◽  
N. Fedoruk ◽  
...  
Keyword(s):  
Mass Fraction ◽  
Dry Matter ◽  
Freezing Point ◽  
Titratable Acidity ◽  
Petri Dish ◽  
Milk Quality ◽  
Quality And Safety ◽  
Protein Mass ◽  
Seeding Method ◽  
Conductivity Increase

The article highlights comparative research results of milk quality indices obtained from the milking in specialized milking halls with such milking units as «Parallel», «Carousel» or in stalls with the milking unit «Molokoprovid». The fat and protein mass fraction, dry matter and fat-free dry matter, density, titratable and active acidity, heat resistance and freezing point have been determined according to the accepted techniques. The electrical conductivity of milk has been determined by using the analytical device MD-20 MAS-D-TEC. The total amount of milk bacteria has been determined by reductase reduction test and by seeding method in Petri dish. The milk quality has been investigated by the fermentation and rennet fermentation tests. The higher indices of the fat mass fraction, the protein mass fraction and the dry substance concentration of milk, obtained in specialized milking halls, have been established. This is not statistically significant. Milk, obtained from the milking unit «Molokoprovid», has higher index of titratable acidity, lower thermal stability in comparison with milk, obtained from specialized milking halls with milking units «Parallel» and «Carousel». It has been determined that there is the bacteria insemination increase in milk received from milking cows in stalls in comparison with milk, obtained from milking in specialized halls. Milk, obtained from the milking unit «Carousel», indicates the subclinical form of mastitis in cows or «Carousel» operation violationif there is in 1,8 mS/cm conductivity increase above average index 4,6 mS/cm. Key words: technology, quality and safety of milk, milking, milking unit, milking hall, bacterial insemination.

Synthesis and Herbicidal Activities of Novel Thiazole PPO Inhibitors

2020 ◽  
Vol 17 (2) ◽  
pp. 192-198
Author(s):  
Shu Chen ◽  
Guihua Ren ◽  
Dan Pei ◽  
Fan Zhang ◽  
Jie Liu ◽  
...  
Keyword(s):  
Petri Dish ◽  
Amaranthus Retroflexus ◽  
Inhibition Rate ◽  
Culture Dish ◽  
Protoporphyrinogen Oxidase ◽  
Nitrobenzoic Acid ◽  
Different Types ◽  
Key Enzyme ◽  
Stem Leaf ◽  
Spray Treatment

Background: Protoporphyrinogen oxidase (PPO, EC 1.3.3.4) is a key enzyme in the biosynthesis of chlorophyll and heme, also the target of different types of herbicides. Thiazole compounds shown excellent biological activity, can be designed by using active groups docking for new PPO inhibitors. Objective: The objective of this study was to synthsize a series of aryl thiazole compounds as PPO inhibitors. Methods: In this study, a series of aryl thiazole compounds derivatives 11a-l were obtained from 2- chloro-5-nitrobenzoic acid as the starting material via esterification, Iron powder reduction, diazotization, Hantzsch reaction and final acylation. All synthesized compounds have been tested for their herbicidal activities as a PPO inhibitors. Results: The Petri dish test indicated that all compounds exhibited good herbicidal activities at 200 mg/L using culture dish. And the post-emergence tests showed that at 150g.ai/ha on weed stem leaf spray treatment, some of the title compounds exhibited 80% inhibition rate against the dicotyledonou weeds Amaranthus retroflexus and Eclipta prostrate. Conclusion: Good activity was noted for some compounds that compounds 11a, 11b, 11c, 11g, 11h had 80% inhibition on stems and leaves of Amaranthus retroflexus at 150g.ai/ha.

scholarly journals In Vitro Ion Release of Wires in Removable Orthodontic Appliances

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3402
Author(s):  
Lena Wepner ◽  
Harald Andreas Färber ◽  
Andreas Jaensch ◽  
Anna Weber ◽  
Florian Heuser ◽  
...  
Keyword(s):  
Mechanical Loading ◽  
Corrosive Medium ◽  
Inductively Coupled Plasma ◽  
Petri Dish ◽  
Orthodontic Appliances ◽  
Testing Time ◽  
Ion Release ◽  
Inductively Coupled ◽  
Corrosive Solution

Various orthodontic wire compositions and configurations are present on the market for removable appliances; however, there have still been only few studies focusing on the effect of resin color and additives such as glitter on corrosion of metallic wires under different conditions. Thus, the aim of the study was to compare concentrations of released ions (aluminium, chromium, nickel) in a corrosive medium under three different conditions: non-loaded wires, loaded wires, and non-loaded wires treated with Kukis® cleaning tablets. Six different wires made of three types of steel alloy were embedded in PMMA resin leaving one centimetre of each wire emerging from the resin to come into contact with the corrosive medium. Glitter particles were added to half of the produced test specimens. For the unloaded test series, five specimens of each group were covered in a petri dish with 50 mL of corrosive medium (pH 2.3) following EN-ISO 10271 for seven days at 37 °C. The wires for the mechanically loaded test specimens overlapped the resin by 5 cm and were clamped into a time-switched electric drive for a defined period of time before the samples were taken after a testing time of 7 days. In the third group, unloaded test specimens were transferred from their petri dishes into the prepared Kukis® solution every 24 h before being stored in the corrosive medium. Inductively coupled plasma mass spectrometry (ICP-MS) was used to quantify the specific ions in the corrosive solution. Statistical analysis showed that the mechanical loading of all wires could significantly raise the diffusion of ions into the corrosive medium. The colour of the resin did not affect the concentration of the released ions. The Kukis® cleaning tabs could not lower the corrosion of the tested metals, as some of the wires were corroded even more using the brace cleanser. Glitter-containing test specimens showed significantly higher amounts of aluminium. Mechanical loading as well as the presence of glitter particles in the resin significantly affected ion concentrations.

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