Abstract: An authentication encryption device generates a mask sequence having, as an element, multiplication, in a Galois field, of a basic mask and a primitive element raised to power of an exponent. The basic mask is defined based on an initialization vector, a secret key, and a constant. The primitive element is a primitive element of a multiplicative group of the Galois field. The exponent differs per cleartext block. The authentication encryption device generates a mask for tag generation by multiplication, in the Galois field, of the basic mask and the primitive element of the multiplicative group of the Galois field raised to power of an exponent differing from the exponent in any of the element in the mask sequence.

Abstract: An authenticated encryption apparatus capable of reducing delays in encryption and in decryption is provided. A nonce generation unit generates a nonce different from any of values generated in the past. A plaintext encryption unit generates a ciphertext corresponding to a plaintext by encrypting each of blocks obtained by dividing the plaintext by using the nonce as an auxiliary variable. A checksum generation unit generates a checksum by using the plaintext. A hash unit acquires a hash value. A nonce encryption unit acquires an encrypted nonce by encrypting the nonce. An authentication tag generation unit generates an authentication tag by using the checksum, the hash value, and the encrypted nonce.

Abstract: A memory address allocation unit allocates, to each of nodes in a tree structure configured for protecting a memory, a memory address unique to the node. A tag generation unit defines, for each of the nodes in the tree structure, a connection of the memory address and a constant as a nonce, and generates a tag by inputting the nonce and a plaintext of which tampering with is to be detected, or the nonce and a plurality of constants of child nodes of each of the nodes into a message authentication code, the message authentication code being a code by which a partially-updatable tag can be output. A node generation unit uses a constant as a local counter, and generates each of the nodes in the tree structure by combining at least a tag and the local counter.

Abstract: The present invention aims at establishing a novel means for purifying norovirus VLPs. There is provided a purification method of norovirus virus-like particles, comprising: contacting solution containing norovirus virus-like particles with support for hydroxyapatite chromatography, binding the virus-like particles to the support, subsequently washing the support with buffer, and then eluting the virus-like particles from the support with buffer containing phosphate, wherein the phosphate concentration of the buffer used for elution is less than 10 mM.

Abstract: The present invention aims at establishing a means for obtaining highly pure virus-like particles by a simple method. There is provided a production method for culture containing virus-like particles, comprising: transforming insect cells with baculovirus vector containing a viral nucleic acid sequence; and cultivating the insect cells, wherein the culture is obtained after continuing cultivating the insect cells until the viability of the insect cells reaches 10% or less.

Abstract: The present invention aims at establishing a novel means for purifying norovirus VLPs. There is provided a purification method of norovirus virus-like particles, comprising: contacting solution containing norovirus virus-like particles with support for hydroxyapatite chromatography, binding the virus-like particles to the support, subsequently washing the support with buffer, and then eluting the virus-like particles from the support with buffer containing phosphate, wherein the phosphate concentration of the buffer used for elution is less than 10 mM.