Gnathostomosis, an emerging foodborne zoonotic disease in Acapulco, Mexico.

A pulse tube refrigerator includes a compressor, a first high pressure valve connected with the compressor, a first high pressure passage connecting the outlet port of the compressor with the first high pressure valve, a first low pressure valve connected with the compressor, first low pressure passage connecting the inlet port of the compressor with the first low pressure valve, a regenerator connected with the first high pressure valve and the first low pressure valve, a cold head connected with the regenerator, a pulse tube connected with the cold head a second high pressure valve connected with the pulse tube. The pulse tube refrigerator further includes a second low pressure valve connected with the pulse tube, a high pressure cylinder provided in the second high pressure passage, a high pressure side partition element reciprocally provided within the high pressure cylinder and fluid tightly dividing the high pressure side cylinder into a first high pressure space and a second high pressure space, a low pressure cylinder provided in the second low pressure passage; and a low pressure side partition element reciprocally provided within the low pressure side cylinder and fluid tightly dividing the low pressure cylinder into a first low pressure space and a second low pressure space.