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The concentration of 111In in breast milk in a 10 weeks postpartum woman was measured at daily intervals up to 72 h post-injection of 5.3 mCi (196 MBq) of 111In-octreotide (OctreoScan). Radiation surveys were also performed at the breast surface. The disappearance of 111In from the breast milk exhibited a bi-exponential pattern with a maximum concentration of 14.2 nCi (0.54 kBq) per 125 ml feeding at 4 h, with lower values thereafter. External surveys at the breast surface also showed a bi-exponential decrease with time. The maximum reading was 8.3 mrem x h(-1) (0.83 mSv x h(-1)) immediately after administration. This rapidly decreased due to 85% urinary excretion by 24 h. Breast milk tracer content and external surveys at the breast surface were determined at 3 h intervals for up to 10 days. If a newborn is nursed for the first 10 days, the internal and external dose equivalents would be 22.97 mrem (0.23 mSv) and 27.86 mrem (0.28 mSv), respectively, for a total of 50.83 mrem (0.5 mSv). The patient was instructed to resume breast-feeding on day 10, when the newborn received a total dose equivalent of 1.55 mrem (0.016 mSv). This dosimetry is based on a very conservative assumption, whereby 100% of the ingested 111In becomes systemic and follows adult bio-behaviour. Oral indium has been shown to be poorly absorbed from the gastrointestinal tract (approximately 0.15%), which suggests the infant's dose could be considerably less. Based on this case report, mathematical relationships are presented for determining the nursing infant's dose equivalent from internal and external exposures relative to time after the maternal administration of 111In-octreotide (OctreoScan).

Досліджено вплив мультистінних вуглецевих нанотрубок (МСВНТ) на формування нанокомпозитів на основі термостійких сітчастих поліціануратів, отриманих in situ поліциклотримеризацією олігомерів диціанового естеру бісфенолу А (ДЦБА) за присутності різного вмісту МСВНТ, та морфологію синтезованих нанокомпозитів, їх структуру і фізико-хімічні властивості. Встановлено, що за невеликого вмісту МСВНТ (0.03—0.06 % мас.) синтезовані нанокомпозити мають високі показники модулю пружності, зафіксовано суттєве підвищення величин межі міцності sр (на 62—94 % у залежності від вмісту МСВНТ), зроблено висновок про взаємодію нанонаповнювача з полімерною матрицею на нанорівні. Исследовано влияние мультистенных углеродных нанотрубок (МСУНТ) на формированние нанокомпозитов на основе термостойких сеточных полициануратов, полученных in situ полициклотримеризацией олигомеров дицианового эстера бисфенола А (ДЦБА) в присутствии различного количества МСУНТ, и морфологию синтезированных нанокомпозитов, их структуру и физико-химические свойства. Установлено, что при небольшом содержании МСУНТ (0.03—0.06 % мас.) синтезированные нанокомпозиты имеют высокие показатели модуля упругости, зафиксировано значительное повышение величины границы прочности sр (на 62—94 % в зависимости от содержания МСУНТ), сделан вывод о взаимодействии нанонаполнителя с полимерной матрицей на наноуровне. An influence of multiwall carbon nanotubes (MWCNT) on formation of nanocomposites based on thermostable polycyanurate networks obtained by in situ polycyclotrimerization of oligomers of dicyanate ester of bisphenol A (DCBA) in the presence of different amount of MWCNT and on their morphology, structure and physical-chemical properties has been studied. It has been found that at low MWCNT content (0.03—0.06 % wt.) the nanocomposites synthesized have high elastic modulus, significant increasing value of strength at break (by 62—94 % depending on MWCNT content) has been observed, the nanoscale interaction of the nanofiller with polymer matrix is discussed.

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As-prepared and annealed layers of polyfluorene were studied by thermoluminescence (TL), photoluminescence (PL) and electroluminescence (EL). Upon annealing at the transition to the liquid-crystalline phase, the green emission in PL and EL becomes more pronounced. At the same time the TL spectrum broadens towards higher temperatures, indicating the introduction of additional trapping sites. In contrast, photooxidation does not broaden the TL spectrum, even so it significantly affects the emission spectra. We conclude that annealing causes the formation of non-/weakly emitting aggregates which compete with the undisturbed chains with respect to charge carrier capture and exciton recombination.