Optimum cutting temperature

Once infiltrated with sucrose, the tissue block is frozen by surrounding it in a liquid, which holds the frozen tissue for sectioning. The most common liquid is optimum cutting temperature or O.C.T. (Sakura Tissue-Tek) another embedding liquid is tissue freezing medium or TFM (Triangle Biomedical Sciences). 

O.C.T. (optimum cutting temperature) - is an embedding liquid used to surround tissue blocks for freezing on a cryostat chuck. 

This chapter describes the rationale behind and means of construction of inexpensive, low to moderate throughput protein arrays. The method of construction is based on injection of analytes into a block of frozen optimum cutting temperature (OCT), the gel media used for frozen sections, and sectioned on a cryostat. The array section is applied to a nitrocellulose pad. Once on nitrocellulose, the array can be utihzed in any fashion desired. The analytes can be any biologic sample including peptides, proteins, antibodies, cells, nucleic acids, or any other material that can tolerate freezing. This platform provides investigators a flexible inexpensive easy-to-fashion platform to create multiplex assays both in the number of samples analyzed and in the types of assays. 

Usually, tissue blocks are held by an optimum cutting temperature (OCT) polymer, but tissues should not be embedded into such polymer reagent because any residual polymer on the tissue slices degrade the mass spectra for both protein and small molecular analysis [10] (see Note 1). 

Optimum cutting temperature (OCT) moimting medium, e.g., Sakura Tissue-Tek OCT Compound (Gentairr, San Jose, CA). 

There are a number of ways to provide the heating or cooling medium at temperatures closer to the optimum level. One is by use of double-effect distillation, which uses the overhead vapor from one column as the heat source for another column such that the second column s reboiler becomes the first column s condenser. This basically cuts the temperature differential in half, and shows up as an energy saving because external heat is suppHed to only one of the units. 

The design has been well proved in quality assurance and origin control of flavours and fragrances. A double-oven system is shown in the Fig. 17.3, with two independent temperature controls and two detectors (DM 1, DM 2). A live switching coupling piece is used to switch the effluent flow to either the first detector or the chiral column. With optimum pneumatic adjustment of the MDGC system, certain fractions are selectively transferred onto the chiral main column as they are eluted from the precolumn (heart-cutting technique) [15]. 

In summary, we have found that the optimum (within the limits of this study) a for shelf-life is 0.54. In addition, the dryer inlet and exit air temperatures had no effect upon oil retention and perhaps only a minor effect upon shelf-life. If there is a significant effect it is that the higher inlet air temperature actually yielded a better shelf-life. A higher temperature differential means that dryer throughput also is increased and operating costs are cut. The more product that can be produced per hour, the lower the production costs. A larger temperature differential also results in a higher final product moisture. 

The subsea flowline and riser conditions can be expected to vary depending on flowline length and diameter, well PI, GDR, water cut, reservoir pressure etc. To Illustrate the possible variation, three cases representing high, optimum and solution GOR are given in Fig. 8. At start-up, temperatures will be circa 5°C, (sea bed temperature) for all cases. 

For practical reasons, the optimum orientation is chosen such that the crystal has a minimum temperature dependence within the intended operating temperature range. Most applications use the AT-cut 35° 15" inclined in the yz-plane, which exhibits a minimum temperature coefficient between 50-70 °C (Janshoff et al., 2000). Yet at the ambient temperatures (25-45 °C) encountered in sensing... 

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