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  • Author: M. Varga x
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Abstract

Energy beets could compete with corn grain as important industrial-sugar feedstocks for biofuels. However, long-term energy beet storage is necessary to maximize processing equipment use, and storage conditions may entirely differ from those established in the sugar industry. This work evaluated combined effects of surface treatment, temperature, and storage atmosphere on beet sugar retention. Initially, beets were dipped in solutions of either a senescence inhibitor (N6-benzylaminopurine) or one of two antimicrobial agents (acetic acid and pHresh 10.0r) at weight fractions of 0.05 and 0.1%, and 0.1 and 1%, respectively. Beets were then stored for up to 36 wk either under aerobic conditions or in sealed containers, at 6ºC or 25ºC. Surface treatment did not show a statistically significant effect on sugar retention. Aerobic storage at 25ºC enabled initial beet sugar retention due to dehydration caused by low relative humidity (37%) in air. In contrast, aerobic storage at 6ºC enabled sugar retention for 24 wk; however, sugar retention decreased sharply thereafter to 56%. This decrease coincided with mold appearance on beet surfaces. Beets stored in sealed containers at both temperatures retained 38% of initial sugars. Increasing surface area to better incorporate preservatives into beet tissue could improve long-term sugar retention.

Abstract

Background: Mycophenolic acid (MPA), a selective inhibitor of lymphocyte proliferation, has lately been used to improve renal function and prolong graft survival in renal transplanted patients. Still, there is no consensus considering the recommended dosing and the therapeutic range of MPA.

Methods: To estimate the safe therapeutic range of MPA, its plasma level and indicators of kidney function were measured in 216 patients (138 male, 78 female, age 46±12 years) 67±46 months after transplantation. Besides MPA, patients received cyclosporine (Group A, n=122) or tacrolimus (Group B, n=77). Seventeen patients (Group C) were treated with MPA in combination with everolimus or sirolimus. Plasma MPA was measured by enzyme inhibition assay.

Results: In the whole study group MPA level increased with the dose of MPA (p=0.013). MPA level was below the therapeutic range in 40% (Group A) and 45% (Group B) of patients, respectively. MPA was 1.9±1.56 mg/L in Group A, 2.4±1.69 mg/L in Group B. In Group A MPA level increased and cyclosporine decreased with the progress of renal disease.

Conclusions: Increasing MPA/cyclosporine ratio at more severe stages of chronic kidney disease was tolerable for the patients and rejection could be avoided. Tubular damage detected by urinary N-acetyl-β-D-glucosaminidase did not correlate with the MPA level.

Abstract

Since the fall of the Iron Curtain illicit trafficking of nuclear and radioactive material has become an issue of concern both on the political and the scientific level. Seized material may be analysed in order to obtain clues on its origin and intended use and to prevent diversion of material from the same source in the future. Nuclear materials (uranium or plutonium) are of particular worry due to the nuclear proliferation risk associated with the material. Nuclear forensic investigations are aimed at the fact that nuclear material carries (inherent) information on its history, including on its origin and the processes applied for its production. Important conclusions can be drawn from decay products, activation products and fission products. Chemical impurities and the isotopic composition of certain major and minor constituents may provide additional information. Comparison of the measured results with nuclear material databases may yield evidence on the production site. The paper will describe the methodologies developed for addressing the above issues, focussing on radiochemical methods. Examples of nuclear forensic casework will illustrate the experience gathered in these areas.

Abstract

In this study the most important analytical methodologies are presented for the nuclear forensic investigation of uranium ore concentrates (yellow cakes). These methodologies allow to measure characteristic parameters which may be source material or process inherited. By the combination of the various techniques (e.g. infrared spectrometry, impurity content, rare-earth pattern and U, Sr and Pb isotope ratio analysis by mass spectrometry), the possible provenances of the illicit material can be narrowed down to a few options and its declared origin can be verified. The methodologies serve for nuclear forensic investigations as well as for nuclear safeguards, checking the consistency of information.