Recent experimentalindicates that the mechanical and electrical properties of many plasticized compositions can be predicted over a wide temperature range if the low frequency transition temperatures of the polymer and plasticizer are known. The transition temperature can be defined as the temperature where the low frequency mechanical damping or dissipation factor is a maximum. This transition temperature is closely related to the second order transition found in these materials. Very close to this same temperature the logarithm of the elastic modulus, as measured by dynamic tests or by such instruments as the torsion tester described by Clash and Berg,4 has an inflection point when plotted against the temperature. This inflection point occurs at a temperature where the polymer is changing from a rigid to a rubbery material, and in the remainder of this paper it will be called the transition temperature T,.For most high polymer-plasticizer systems, the transition temperature is a linear function of the volume fraction of plasticizer in the system if the plasticizer is compatible with the p~l y m e r .~.~.~ For such systems the complete transition temperature-composition curve can be predicted from two points such as the transition temperatures of the pure polymer and plasticizer. Data on several such compatible systems will be presented. Data will also be given which indicate that in many cases copolymers may be considered as a polymer-plasticizer system in which the one component acts as an internal plasticizer for the other. When these conditions are realized, the transition temperature of a copolymer can be estimated from the transition temGeratures of the pure polymers and the composition of the copolymer.All the data were obtained using the torsional apparatus of Clash and Berg.4 The angles of twist were recorded 5 seconds after the force was applied to the specimen. The error in the transition temperature cannot be considered smaller than * 1°C.
Patient: Male, 81
Final Diagnosis: Mantle cell lymphoma
Symptoms: Dificulty in swallowing and pain in the right ear
Medication: —
Clinical Procedure: Otorhinolaryngology panendoscopy • biopsy of the tumors
Specialty: Otolaryngology
Objective:
Rare disease
Background:
Radiation, specifically ionizing radiation, causes broad-spectrum gene damage, including double-strand DNA breaks, single DNA strand breaks, cross links, and individual base lesions, thus causing chromosomal translocations, deletions, point mutations, and, consequently, various types of cancer. Radiation also causes genomic instability in cells, which enhances the rate of mutations in the descendants of the irradiated cell after many generations of normal replications.
Case Report:
We report the first case of mantle cell lymphoma of the torus tubarius, and the first CD10-positive mantle cell lymphoma of the Waldeyer’s ring. Mantle cell lymphoma appeared 65 years after treatment of chronic sinusitis with nasopharyngeal radium irradiation.
Conclusions:
On the basis of the medical literature about atomic bomb survivors, nuclear plant workers, and radiologists exposed to radiation, and our case, we conclude that radiation can, in a very small percentage of exposed individuals, cause non-Hodgkin lymphoma: in 0.24% of atomic bomb survivors and in at least 0.13% of the patients treated with nasopharyngeal radium irradiation.
Non-Hodgkin lymphoma can occur many decades after radiation exposure, and individuals treated with nasopharyngeal radium irradiation, usually in their childhood, need continuing follow-up.
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