Attempts to chemically investigate element 112

Two experiments aiming at the chemical investigation of element 112 produced in the heavy ion induced nuclear fusion reaction of 48Ca with 238U were performed at the Gesellschaft für Schwerionenforschung (GSI), Darmstadt, Germany. Both experiments were designed to determine the adsorption enthalpy of element 112 on a gold surface using a thermochromatography setup. The temperature range covered in the thermochromatography experiments allowed the adsorption of Hg at about 35 °C and of Rn at about -180 °C. Reports from the Flerov Laboratory for Nuclear Reactions (FLNR), Dubna, Russia claim production of a 5-min spontaneous fission (SF) activity assigned to 283112 for the 238U(48Ca,3n) 283112 reaction. Hence, Experiment I was designed to detect spontaneously fissioning (SF) isotopes of element 112 with half-lives (t 1/2) longer than about 20 s. 11 high-energy events were detected. 7 events exhibit a deposition pattern resembling a chromatographic peak in the vicinity of Rn deposition. However, the energy of the events observed in Experiment I was lower than expected for a SF-decay of 283112. Therefore, these events could not be unambiguously attributed to the decay of 283112. In contradiction with earlier publications newer reports from FLNR Dubna claim that 283112 decays by α-particle emission (E α = 9.5 MeV) with t 1/2 = 4 s followed by a SF-decay of 279Ds (t 1/2 = 0.2 s). Therefore, Experiment II was designed to be sensitive to both claimed decay properties of 283112. However, during this experiment neither short α-SF correlations nor SF coincidences were detected. The conclusion is that 283112 was not unambiguously detected, neither in Experiment I nor in Experiment II.

Extraction separation of No-carrier-added astatine from bismuth target

Alpha particle activation of natural Bi2O3 results in the formation of astatine radionuclides. A simple and rapid separation method of astatine is presented from the bulk target matrix bismuth by employing liquid-liquid extraction (LLX) method using methylisobutylketone (MIBK) and hydrochloric acid. Back extraction of astatine was performed by ethylenediaminetetraacetic acid (EDTA) solution at pH 10.

Separation of carrier-free cerium radionuclides from different target matrix produced by heavy ion beams

Heavy ion activation of natural Sb2O3 with 78 MeV 16O6+ results in the formation of carrier-free praseodymium isotopes, 133,135Pr, and their corresponding decay products 133,135Ce, in the matrix. Also irradiation with ~ 90 MeV 19F7+ beam leads to the production of carrier-free neodymium isotopes, 135-138Nd, which decay out to 135-138Ce via 135-138Pr. Another way for the production of carrier-free 135Ce radionuclide is to irradiate CsNO3 target with 7Li3+ beam of energy 44 MeV. The shorter lived radionuclides of cerium decay out and a radiochemical procedure has been developed for the separation of carrier-free radionuclides from the bulk target matrix antimony and caesium through liquid-liquid extraction (LLX) using Aliquat 336 (tricaprylmethylammonium chloride), and di-(2-ethylhexyl)phosphoric acid (HDEHP) as extractants.

Nucleic acid probes in periodontal diagnosis

Periodontal Disease is considered as an infection caused by a variety of microorganisms. Considering the vast range of microbial species involved in the causation of periodontal diseases, a specific diagnostic procedure, to identify the various organisms involved is a major necessity. A number of diagnostic procedures, including microbiological and immunological have been utilized in the diagnosis of periodontal disease. The DNA probe technology provides both a sensitive and specific assay and also alleviates concern for transport of the fastidious microorganisms in clinical samples, fulfills the need for a specific and rapid test, that does not require the preservation of viable microorganisms. DNA probes are now being used to identify the various putative pathogen's including; A. actinomycetemcomitans, P. gingivalis, P. intermedia, B. forsythus, etc. Besides DNA probes have also been proven an advantage over the various other available procedures in periodontal diagnosis.

HbA1c predicts length of stay in patients admitted for coronary artery bypass surgery

Diabetes mellitus is associated with coronary artery disease, and diabetic patients are frequently referred for coronary bypass graft surgery. It is well known that HbA1c, which reflects long-term glycemic control, is related to diabetic morbidity and mortality. It is not known whether HbA1c is related to postoperative length of stay among patients who undergo coronary artery bypass surgery. The authors evaluated 135 patients who underwent bypass surgery at the Westchester Medical Center (Valhalla, NY). HbA1c was measured in all patients preoperatively; a value of 7% or greater was used as a threshold for uncontrolled hyperglycemia. A postoperative length of stay of 6 days or more was used as the cutoff for an extended length of stay. Linear regression was used to assess the relationship between HbA1c, adjusted for age, and length of stay in days. Logistic regression, with length of stay a binary variable <6, > or =6 days, was used to assess the accuracy of HbA1c <7%, > or =7%, adjusted for age, in predicting length of stay. An HbA1c of 7% or greater was found to be a strong predictor of a length of stay of 6 days or longer. These data suggest that HbA1c can be used as a surrogate marker for cardiac and noncardiac morbidity that prolongs hospitalization after coronary artery bypass surgery.

Alternative methods for the production of carrier-free (66,67)Ga

Heavy ion activation of natural cobalt foil with 52 MeV 11B4+ and 73 MeV 12C6+ results in the formation of carrier-free (66,67)Ge and (66,67)As radionuclides, respectively, along with their corresponding decay products, (66,67)Ga in the matrix. The carrier free gallium radionuclides have been separated from the bulk target matrix cobalt by employing liquid-liquid extraction method using TOA as liquid anion exchanger.

Multitracer techniques: applications in chemical and life sciences

The scope and approaches of the "multitracer technique" have briefly been reviewed. The various aspects of the "multitracer technique" include, the methods of accelerator production of "multitracers" and their separation, the application of this technique in the study of adsorption of metal ions on solid surfaces and in the study of distribution of trace elements in plants and animals.

Enamel matrix derivative in periodontal reconstructive surgery. A new approach in periodontal regeneration

True periodontal regeneration is the goal of any periodontal regenerative techniques. Cementum formation is a key event in the development of root and supporting periodontium. Due to its distribution, acellular cementum is the type most affected by early to moderate periodontitis. Studies over the past twenty years demonstrated that, enamel matrix proteins from the root sheath are involved in the formation of acellular, during tooth development. Thus the adjunctive use of enamel matrix derivatives in conjunction with regenerative periodontal surgery could possibly lead to true periodontal regeneration. The purpose of this article is to review the use of enamel matrix derivative in true periodontal regeneration.

Production and separation of carrier-free 145,146Eu from a CsNO3 target using a 16O beam

Carrier free europium isotopes 145,146Eu have been produced by irradiating a CsNO3 target with an 80 MeV 16O beam. Radiochemical separation of the produced europium isotopes from the bulk target matrix of CsNO3 have effectively been done using HDEHP, the liquid cation exchanger.

Separation of carrier-free hafnium and lutetium radionuclides produced in 16O activated terbium metal target

Charged particle activation with approximately 88 MeV 16O7+ beam on natural terbium metal foil leads to the production of the short lived carrier-free radioisotopes 170,171Ta and their corresponding daughter products 170,171Hf and 170,171Lu in the target matrix. Liquid-liquid extraction with HDEHP diluted in cyclohexane was carried out for the separation of 170,171Hf and 170,171Lu from the bulk terbium in an aqueous HCl medium.