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The CEA in collaboration with ILL and LPSC has developed a measurement program on symmetric and heavy mass fission product distributions. The combination of measurements with ionisation chamber and Ge detectors is necessary to describe precisely the heavy fission product region in mass and charge. Recently, new measurements of fission yields and kinetic energy distributions, for different fissioning systems (233,235 U(nth, f),241 Am(2nth, f) and 239,241 Pu(nth, f), were performed with recoil spectrometer LOHENGRIN. The focus has been done on the self-normalization of the data to provide new absolute measurements, independently of any libraries along with the experimental covariance matrix. To reach precise measurements, a new experimental procedure was developed along with a new analysis method.

Nuclear fission yields are key parameters to evaluate reactor physics observables, such as fuel inventory, decay heat, spent fuel radiotoxicity, criticality but also for understanding the fission process. Despite a significant effort allocated to measure fission yields during the last decades, the recent evaluated libraries still need improvements in particular in the description of the uncertainties with the associated correlations. Additional kinds of measurements provide complementary information in order to test the models used in the nuclear data evaluation. Moreover, some discrepancies between these libraries must be explained. A common effort by the CEA, the LPSC and the ILL aims at tackling these issues by providing precise measurement of isotopic and isobaric fission yields with the related variance-covariance matrices. Nevertheless, the experimental program represents itself a large range of observables requested by the evaluations: isotopic yields, nuclear charge polarization, odd-even effect, isomeric ratio and their dependency with fission fragment kinetic energy as a probe of the nuclear de-excitation path in the (E*, Jπ) representation. Measurements for thermal neutron induced fission of 241Pu have been carried out at the Institut Laue Langevin using the LOHENGRIN mass spectrometer. Experimental program, observables reachable, results and comparison to model calculations are shown.

In this article we report on the observation of new yrast and non-yrast states in $^{136}\mathrm{I}$, populated in the prompt-$\ensuremath{\gamma}$ spectroscopy EXILL campaign at the ILL using both $^{235}\mathrm{U}$(n,f) and $^{241}\mathrm{Pu}$(n,f) reactions. We propose an extension of the level scheme and interpretation of the new spectroscopic results in comparison to state-of-the-art shell-model calculations. We discuss the role of the proton ${d}_{5/2}$ orbital in the structure of this nucleus with $Z=53$ and the energy split between the $\ensuremath{\pi}{d}_{5/2}\phantom{\rule{0.28em}{0ex}}\text{and}\phantom{\rule{0.28em}{0ex}}\ensuremath{\pi}{g}_{7/2}$ orbitals. We also provide a complete overview of all experimental information about this nucleus and include new data from $^{252}\mathrm{Cf},^{248}\mathrm{Cm}$ fission and $\ensuremath{\beta}$ decay of $^{136}\mathrm{Te}$ to $^{136}\mathrm{I}$. We give a new interpretation of $^{136}\mathrm{I}$ and its decay to $^{136}\mathrm{Xe}$ in terms of the influence of the neutron ${h}_{9/2}$ orbital and the Gamow-Teller strength for $N=83$.

Excited states in $^{98}\mathrm{Y}$, populated in neutron-induced fission of $^{235}\mathrm{U}$ and in spontaneous fission of $^{248}\mathrm{Cm}$ and $^{252}\mathrm{Cf}$, have been studied by means of $\ensuremath{\gamma}$ spectroscopy using the Lohengrin fission-fragment separator at ILL Grenoble and the EXILL, Eurogam2, and Gammasphere Ge arrays. Two new isomers have been found in $^{98}\mathrm{Y}$: a deformed one with ${T}_{1/2}=180(7)$ ns and a rotational band on top of it, and a spherical one with ${T}_{1/2}=0.45(15)\phantom{\rule{4pt}{0ex}}\ensuremath{\mu}\text{s}$, analogous to the ${8}^{+}$ isomer in $^{96}\mathrm{Y}$, corresponding to the ${(\ensuremath{\nu}{g}_{7/2},\ensuremath{\pi}{g}_{9/2})}_{{8}^{+}}$ spherical configuration. Using the JYFLTRAP Penning trap, an accurate excitation energy of 465.7(7) keV has been determined for the 2.36-s isomer in $^{98}\mathrm{Y}$. This result and the studies of excited levels in $^{98}\mathrm{Zr}$, populated in ${\ensuremath{\beta}}^{\ensuremath{-}}$ decay of the isomer, indicate a new spin-parity, ${I}^{\ensuremath{\pi}}={(7)}^{+}$ for the isomer. The high spin and the decay properties of this isomer suggest the presence of the $9/{2}^{+}[404]$ neutron extruder orbital in its structure. This is consistent with the large deformation of the isomer, reported recently. The present work does not provide arguments to support the special role of the $\ensuremath{\nu}{g}_{7/2}\phantom{\rule{0.16em}{0ex}}\text{\ensuremath{-}}\phantom{\rule{0.16em}{0ex}}\ensuremath{\pi}{g}_{9/2}$ interaction (the spin-orbit-partner, or SOP, mechanism).

International audience; FIPPS is the new nuclear physics instrument of ILL for the spectroscopy of nuclei produced in neutron-induced reactions. The performance of the first implementation of the setup will be shown, together with an overview of the first experimental campaign (December 2016-March 2017). Future perspectives and physics opportunities will then be discussed.

After entering the blood, bisphosphonates are immediately bound to bone or excreted unchanged by the kidney. During renal excretion about 0.5% of administrated dosage remains in kidney tissue. The renal tissue level of bisphosphonates (RTL) decreases over time and remains at about 0.15% after 3weeks, but the influence of renal insufficiency (RI) is unclear.We investigated the influence of mild to moderate RI on RTL of ibandronate (IBD). First a method for determination of RTL was implemented and validated. We measured RTL in rats with normal renal function (SHAM) and after unilateral nephrectomy (UNX). In each case one SHAM and one UNX groups received one or alternatively 9 times every 3weeks a dosage of 1.5mg/kg IBD. After the last dosage the rats were sacrificed and RTL of IBD were determined.In SHAM-rats IBD concentrations increased from 272.7ng/g kidney after one injection to 428.9ng/g kidney after nine injections (p0.0001). RTL in UNX rats likewise increased significantly (p0.0001) from 289.9ng/g kidney to 520.2ng/g kidney.Our study found a 1.6 fold increase of RTL in SHAM rats and a 1.8 fold increase of RTL in UNX rats after nine versus one injection. As steady state is generally reached after five half-lives we anticipate no further accumulation on continued treatment.

Isomeric ratios are a powerful observable to investigate fission fragment total angular momenta. A recent experimental campaign achieved at the LOHENGRIN spectrometer, shows a kinetic energy dependence of μs isomeric ratios from fission fragments populated in neutron induced fission of 235U. For the first time, this dependence was measured for the isomeric ratio of the doubly magic 132Sn. A Bayesian assessment of the angular momentum distribution of 132Sn is proposed according to calculations performed with the FIFRELIN code and interpreted with spin generation models. Keywords: Isomeric ratio, Mass spectrometer, Angular momentum distribution, Fission fragment

International audience; Fission yields are essential for nuclear reactor studies (decay heat, fuel inventory…) and constitute also one of the main observables needed to improve our understanding of the fission process. The symmetric mass region is of particular interest due to various intriguing properties of the fission fragments already reported in the literature : inversion of the nuclear charge polarization, large width of the fission fragment kinetic energy distribution, strong change of the prompt neutron multiplicity, etc. Recently, measurements of fission yields and kinetic energy distributions in the symmetric mass region were achieved at the LOHENGRIN mass spectrometer of the Institut Laue-Langevin (ILL). This experimental work is challenging due to the low counting rate and the appearance of contaminant masses, leading to pronounced components in the fission fragment kinetic energy distribution. Despite removing the undesirable contributions, the fission fragment kinetic energy distributions still show two components, indicating that the fission process could be modal. To go further and better characterize these components a comparison between our experimental data and Monte Carlo calculations (FIFRELIN code) simulating the de-excitation of the fission fragments for different fission channels will be presented and discussed.

The characterisation of fragments from nuclear fission in terms of excitation energy and spin population is still a debated subject. We show that data on excitation energy, kinetic energy and spin of the fragments in thermal neutron induced fission of the actinides can be consistently described by the statistical model in nuclear physics. We present an empirical relationship which allows calculating the temperature of fission products at the scission point. From the temperature we derive the distribution functions for excitation, kinetic energy and fragment spin. We compare the results from the statistical model with experimental data from the LOHENGRIN spectrometer at the Institut Laue-Langevin in Grenoble/France.

communication - http://hal.in2p3.fr/in2p3-00797322; International audience; Analysis and results of the measurements of the independent isotopic and mass fission yieldsfor the 233U(nth,f) reaction are presented, which were performed at the Lohengrin recoil massspectrometer in ILL. The spectrometer separates the fission products according to their mass toion charge ratio and kinetic energy to ion charge ratio. Mass yields were obtained by means ofan ionisation chamber after separation by the spectrometer. Isotopic yields were determined byplacing two high-purity Germanium clover detectors downstream the spectrometer. An innovativeanalysis method developed for the Lohengrin spectrometer is presented, from which the final resultsare independent from the previous evaluations, which is usually not the case.

International audience; The study of fission yields has a major impact on the characterization and understanding of the fission process and is mandatory for reactor applications. The LPSC in collaboration with ILL and CEA has developed a measurement program on fission fragment distributions at the Lohengrin spectrometer of the ILL, with a special focus on the masses constituting the heavy peak. We will present in this paper our measurement of the very low fission yields in the symmetry mass region and the heavy mass wing of the distribution for 233U thermal neutron induced fission. The difficulty due to the strong contamination by other masses with much higher yields will be addressed in the form of a new analysis method featuring the required contaminant correction. The apparition of structures in the kinetic energy distributions and possible interpretations will be discussed, such as a possible evidence of fission modes.

International audience; Within the EXILL campaign a large and efficient cluster of Ge-detectors was installed around a very well collimated neutron beam. This has allowed to carry out rather complete spectroscopic studies close to the line of stability using the (n,γ) reaction. Neutron rich isotopes were produced by neutron induced fission and prompt spectroscopy was carried out. The isotope selection in this setup was based on a partially known level scheme and the use of triple coincidences. The latter is limiting the statistical sensitivity in the case of weak production yields. Based on the experiences of these campaigns we are currently developing a new setup: FIPPS (FIssion Product Prompt Spectroscopy). This setup combines a collimated neutron beam, a highly efficient cluster of Ge detectors, a gas filled magnet and auxiliary detectors. The presence of the gas filled magnet will allow us to identify fission products directly and should give access to a new quality of studies if compared to the EXILL campaign. The EXILL campaign and the FIPPS project are presented.

SUMMARYAutoantibodies to CRP were reported previously in patients suffering from toxic oil syndrome. This syndrome resembles autoimmune diseases such as systemic lupus erythematosus (SLE) or systemic scleroderma. We therefore examined the prevalence of antibodies to CRP and other acute-phase proteins in autoimmune diseases, including SLE, subacute cutaneous lupus erythematosus (SCLE), systemic scleroderma (SSc), and primary biliary cirrhosis (PBC), as well as in bone marrow transplantation-induced chronic graft-versus-host disease and eosinophilia–myalgia syndrome. IgG antibodies to CRP were found in 78% of SLE and in 30% of SCLE patients, while 16% of patients with PBC were positive. In up to 45% of patients with SSc predominantly IgG antibodies to ceruloplasmin were detectable. Lack of systemic involvement as in discoid lupus erythematosus and localized scleroderma (morphea) correlated with low or absent antibody formation. However, no correlation was found between anti-acute-phase protein antibodies with liver disease or other organ involvement. Adsorption studies revealed that non-native epitopes on the CRP molecule, termed modified CRP, are the main target of antibodies. Chronic inflammatory tissue injury in systemic autoimmune disease might increase the presentation of cryptic epitopes of CRP to the threshold required for T cell activation.

The spectroscopy of the prompt gamma decay from fission products gives information on the entry states, e.g. distribution functions for excitation energy and spin, and therefore a direct link to the fission process itself. This type of spectroscopy is, however, only possible when a filter can be constructed which allows setting a gate to the gamma-spectrum in a narrow region in mass and nuclear charge, as well as on the total excitation energy of the fragment split under investigation. A possible configuration of a prompt gamma-ray spectrometer consist of a gamma-ray array composed of high resolution germanium detectors, coupled to a gas filled magnet. We will outline the principles for a gas filled magnetic spectrometer for fission product spectroscopy. In particular the focusing characteristics of such a device, which are valid for particles in the velocity regime of E/A< 1MeV/amu, will be addressed. First experiments on the LOHENGRIN spectrometer in Grenoble investigating on the behavior of fission products in gas filled magnets have been performed, and have validated the experimental approach to the nuclear fission process with such a device. Much work has been done over the last 75 years to measure observables in nuclear fission, mostly fission product mass, nuclear charge, and kinetic energy. The distributions of these observables are strongly dependent on mass and charge of the fissioning compound system, and the excitation energy which is given to the system to induce the fission process. Accessible are mostly secondary fission product distributions, after the emission of prompt neutrons and gamma rays. Standard measurements of mass and kinetic energy are done by measuring the kinetic energy of both fragments with the help of ionisation chambers or surface barrier detectors. By the measurement of the ratio of the two kinetic energies, and the assumption that both fragment masses add up to the compound nucleus mass, a rough idea of the mass distribution can be obtained, as well as a rough idea about the total kinetic energies by doing assumptions on the neutron evaporation process. A step further to obtain distribution functions for fission products is the combined measurement of the two velocities and the two kinetic energies of both fission products, which allows the reconstruction of the primary quantities of mass and total

communication - http://hal.in2p3.fr/in2p3-00797284; International audience; The Lohengrin mass spectrometer is one of the 40 instruments built around the reactor of the Institute Laue-Langevin (France) which delivers a very intense thermal neutron flux. Usually, Lohengrin was combined with a high-resolution ionization chamber in order to obtain good nuclear charge discrimination within a mass line, yielding an accurate isotopic yield determination. Unfortunately, this experimental procedure can only be applied for fission products with a nuclear charge less than about 42, i.e. in the light fission fragment region. Since 2008, a large collaboration has started with the aim of studying various fission aspects, mainly in the heavy fragment region. For that, a new experimental setup which allows isotopic identification by γ-ray spectrometry has been developed and validated. This technique was applied on the 239Pu(nth,f) reaction where about 65 fission product yields were measured with an uncertainty that has been reduced on average by a factor of 2 compared with what was that previously available in nuclear data libraries. The same γ-ray spectrometric technique is currently being applied to the study of the 233U(nth,f) reaction. Our aim is to deduce charge and mass distributions of the fission products and to complete the experimental data that exist mainly for light fission fragments. The measurement of 41 mass yields from the 241Am(2nth,f) reaction has been also performed. In addition to these activities on fission yield measurements, various new nanosecond isomers were discovered. Their presence can be revealed from a strong deformed ionic charge distribution compared to a 'normal' Gaussian shape. Finally, a new neutron long-counter detector designed to have a detection efficiency independent of the detected neutron energy has been built. Combining this neutron device with a Germanium detector and a beta-ray detector array allowed us to measure the beta-delayed neutron emission probability Pn of some important fission products for reactor applications.

The accurate knowledge of the fission of actinides is necessary for studies of innovative nuclear reactor concepts. The fission yields have a direct influence on the evaluation of the fuel inventory or the reactor residual power after shutdown. A collaboration between the ILL, LPSC and CEA has developed a measurement program on fission fragment distributions at ILL in order to measure the isotopic and isomeric yields. The method is illustrated using the 233 U(n,f) 98 Y reaction. However, the extracted beam from the Lohengrin spectrometer is not isobaric ions which limits the low yield measurements. Presently, the coupling of the Lohengrin spectrometer with a Gas Filled Magnet (GFM) is studied at the ILL in order to define and validate the enhanced purification of the extracted beam. This work will present the results of the spectrometer characterisation, along with a comparison with a dedicated Monte Carlo simulation especially developed for this purpose.

Objective: This study aimed to examine the contributions of coping and social constraint to disease activity and health-related quality of life (HRQOL) and to examine group differences in disease activity and HRQOL between patients with high versus low anxiety or depression symptoms in adults with inflammatory bowel disease (IBD). Methods: This study was a retrospective analysis in which disease activity was measured with either the Harvey-Bradshaw Index or the Simple Clinical Colitis Activity Index. HRQOL was measured with the Short Inflammatory Bowel Disease Questionnaire. Coping was measured with a modified COPE questionnaire. Anxiety and depression symptoms were measured with the Hospital Anxiety and Depression Scale. Social constraint was measured with the Social Constraint Questionnaire. Correlational and regression analyses were performed to assess the relationships between social constraint, coping, anxiety symptoms, depression symptoms, and HRQOL and disease activity. Results: Data from 80 adults with IBD were reviewed. Social constraint, disengagement coping, anxiety symptoms, and depression symptoms were inversely correlated with HRQOL. Disengagement coping was positively correlated with disease activity. Regression analyses showed that smokers had significantly worse HRQOL than nonsmokers and that greater use of engagement coping was associated with significantly diminished HRQOL. Regression analyses also showed that patients diagnosed between 17 and 40 years of age were significantly less likely to have active disease than patients diagnosed before 16 years of age and that greater use of disengagement coping was associated with increased odds of having active disease. Conclusions: Medical providers should be aware that coexisting social constraint and symptoms of anxiety and depression are common in patients with IBD. Screening for these factors, as well as patients' coping styles, should be strongly considered, and patients should be referred to mental health providers as appropriate.

Fission fragments from neutron-induced fission of ${}^{235}$U produced at the high-flux reactor of the Institut Laue-Langevin, Grenoble, were separated with the Lohengrin separator to provide a beam of neutron-rich ${}^{85}\phantom{\rule{-0.16em}{0ex}}$As nuclei. The ${\ensuremath{\beta}}^{\ensuremath{-}}$ decay of ${}^{85}\phantom{\rule{-0.16em}{0ex}}$As to ${}^{85}$Se was studied using $\ensuremath{\gamma}$-$\ensuremath{\gamma}$ and $\ensuremath{\beta}$-$\ensuremath{\gamma}$ coincidence techniques. ${}^{85}$Se was also studied using the prompt-$\ensuremath{\gamma}$ coincidence data from spontaneous fission of ${}^{248}$Cm and ${}^{252}$Cf measured with the Eurogam2 and Gammasphere Ge arrays, respectively. The combination of $\ensuremath{\beta}$ decay and prompt-$\ensuremath{\gamma}$ data enabled the determination of spins and parities of low-energy excited states in ${}^{85}$Se. There are new arguments supporting the $5/{2}^{\ensuremath{-}}$ assignment for the ground state of ${}^{85}\phantom{\rule{-0.16em}{0ex}}$As.

Some neutrons are emitted from fission products seconds to minutes after fission occurs. The knowledge of these delayed neutrons is essential in the field of nuclear energy. But the probabilities to emit such delayed neutrons (Pn) are not always well known. A summary of different databases and compilations of Pn values is presented to show these discrepancies and uncertainties. The usual methods used to determine these nuclear data are then reviewed with an emphasis on biases and systematic errors to be avoided. To measure precise Pn values, a new neutron LOng-counter with ENergy Independant Efficiency (LOENIE) has been built for the LOHENGRIN separator facility installed at Institut Laue Langevin (FRANCE). Its characteristics and first results obtained are presented.

Highly refined mineral hydrocarbons (MHCs) such as low melting point paraffin wax (LMPW) and low viscosity white oils can cause inflammatory changes in the liver and mesenteric lymph nodes (MLNs) of the Fischer-344 (F-344) rat. In contrast, only minimal MLN changes are seen in the Sprague-Dawley (S-D) rat with no changes in the liver. In this study, the response of female F-344 and S-D rats was compared after 90days dietary treatment with 0%, 0.2% or 2% LMPW. Effects in the F-344 rats were significantly greater than in the S-D rats: increased liver and splenic weights and inflammatory changes (hepatic microgranulomas) in these tissues were observed only in the F-344 rats. Microgranulomas in the MLNs were observed in both strains but the effects were substantially greater in the F-344 rats. Cellular markers of inflammation were examined in a subset of rats from each group using immunohistochemical staining. An increase in staining for CD3 (T-cells), CD8a (suppresser/cytotoxic T-cells) and CD4 (helper T-cells) correlated with an increase in lymphoid cells in the livers of treated F-344 rats. The majority of macrophages in the hepatic microgranulomas of treated F-344 rats were negative for the ED2 marker, indicating a likely origin from non-resident macrophages. Electron microscopy showed Kupffer cell hypertrophy and hyperplasia in treated F-344 rats. However, lysozyme staining (indicating activation of epithelioid macrophages) decreased with increasing granuloma size. Non-ED2 expressing cells may have been recruited but not sufficiently activated to be lysozyme positive. Inflammatory changes in the cardiac mitral valve noted in previous studies of LMPW were also seen in the F-344 rats in this study but not in the S-D rats. Chemical analysis showed that MHC accumulated in livers from treated F-344 but not S-D rats and the concentration was more than 2-fold greater in MLNs from the F-344 than from the S-D rats. The F-344 appears to be more immunologically sensitive to a number of agents than other rat strains and the results of this study suggest that this may contribute, along with pharmacokinetic differences, to the inflammatory response of F-344 rats to dietary MHCs.

International audience; The modelling of γ heating and neutron damage inside a nuclear reactor is essential to design the next generation of nuclear reactors. The determination of the fission fragment momentum is a key element to perform accurate calculations of the γ heating. One way to assess this information is to look at the isomeric ratio of different nuclei. According to the lifetime of the isomeric state, different experimental techniques were developed at the LOHENGRIN spectrometer. A focus on the measurement of isomeric ratios of 136I in neutron induced fission of 241Pu is presented. A discussion with the current assumptions used in the evaluation process for isomeric ratio is also shown.

A more accurate knowledge of heavy fission product yields is needed to improve our understanding of the fission process and to increase the efficiency in nuclear reactor operation. High resolution measurements of fission observables can be done with the recoil mass spectrometer Lohengrin at the Institut Laue-Langevin in Grenoble, France, which was designed to measure fission fragment characteristics from neutron induced fission. The mass separator is situated at the research reactor of the institute and permits the placement of an actinide layer in a high thermal neutron flux. It separates fragments according to atomic mass, kinetic energy and ionic charge state by the action of magnetic and electric fields, and allows to determine these distributions, isotopic yields, and the fragment gamma-decay characteristics. Almost all fissile isotopes rangings from Th to Cf have been investigated with Lohengrin, and in particular mass and nuclear charge distributions for light fission products have been determined. The experimental set-up used to investigate the mass yield and the fission fragment kinetic energy distributions in the heavy mass region, or in the light mass region, is done by coupling a high resolution ionization chamber to the spectrometer. For low mass fission products a double anode ionization chamber is used to determine furthermore isotopic yields within a mass line. For fission fragments of higher mass this separation is no longer possible, and gamma-spectrometry is used instead to identify the contributing nuclear charges. The experimental set-up is shortly described in the present paper, and we present preliminary results for measurements of thermal neutron induced fission in 235 U(nth, f), 239 Pu(nth ,f ) and 241 Pu(nth, f).

The half-life of the 830.2-keV isomeric state in {sup 97}Sr, for which very different values are reported in the literature, has been measured. The experiment performed at the LOHENGRIN fission-fragment separator consisted of two independent measurements. The two measurements provided consistent results. The weighted average value, T{sub 1/2}=526(13) ns, supports the interpretation of the 830.2-keV state in {sup 97}Sr, as the 9/2{sup +}[404] neutron-hole configuration.

Microsecond isomers of neutron-rich nuclei in masses $A=96$ and 98 were reinvestigated at the Institut Laue-Langevin reactor (Grenoble). These nuclei were produced by thermal-neutron induced fission of $^{241}\mathrm{Pu}$. The detection is based on the time correlation between fission fragments selected by the Lohengrin mass spectrometer and the \ensuremath{\gamma} rays and conversion electrons from the isomers. A new level scheme of $^{96}\mathrm{Rb}$ is proposed. We have found that the ground state and low-lying levels of this nucleus are rather spherical, and a rotational band develops at 461-keV energy. This band has properties consistent with a $\ensuremath{\pi}[431\phantom{\rule{0.3em}{0ex}}3/2]\ifmmode\times\else\texttimes\fi{}\ensuremath{\nu}[541\phantom{\rule{0.3em}{0ex}}3/2]K={3}^{\ensuremath{-}}$ Nilsson assignment and a deformation ${\ensuremath{\beta}}_{2}g0.28$. It is fed by a ${I}^{\ensuremath{\pi}}={10}^{\ensuremath{-}}$ microsecond isomer consistent with a $\ensuremath{\pi}({g}_{9/2})\ensuremath{\nu}({h}_{11/2})$ spherical configuration. It is interesting to note that the same unique-parity states $\ensuremath{\pi}({g}_{9/2})$ and $\ensuremath{\nu}({h}_{11/2})$ are present in the same nucleus in a deformed and in a spherical configuration. The neighboring odd-odd nucleus $^{98}\mathrm{Y}$ presents a strong analogy with $^{96}\mathrm{Rb}$ and is also discussed.

Microsecond isomers in the In and Cd isotopes, in the mass range A = 123 to 130, were investigated at the ILL reactor, Grenoble, using the LOHENGRIN mass spectrometer, through thermal-neutron induced fission reactions of Pu targets. The level schemes of the odd-mass $^{123-129}$In are reported. A shell-model study of the heaviest In and Cd nuclei was performed using a realistic interaction derived from the CD-Bonn nucleon-nucleon potential

ACE; This paper deals with the comparison between thermal and Fission Enhanced Diffusion (FED) of uranium into zirconia, representative of the inner face of cladding tubes. The experiments under irradiation are performed at the Institut Laue Langevin (ILL) in Grenoble using the Lohengrin spectrometer. A thin $^{235}UO_2$ layer in direct contact with an oxidized zirconium foil is irradiated in the ILL high flux reactor. The fission product flux is about 10$^{11}$ ions cm$^{-2}$ s$^{-1}$ and the target temperature is measured by an IR pyrometer. A model is proposed to deduce an apparent uranium diffusion coefficient in zirconia from the energy distribution broadening of two selected fission products. It is found to be equal to 10$^{-15}$ cm$^2$ s$^{-1}$ at 480$\circ$C and compared to uranium thermal diffusion data in ZrO$_2$ in the same pressure and temperature conditions. The FED results are analysed in comparison with literature data.

Microsecond isomers in the In and Cd isotopes, in the mass range $A=123\phantom{\rule{0.3em}{0ex}}\text{to}\phantom{\rule{0.3em}{0ex}}130$, were investigated at the ILL reactor, Grenoble, using the LOHENGRIN mass spectrometer, through thermal-neutron induced fission reactions of Pu targets. The level schemes of the odd-mass $^{123--129}\mathrm{In}$ and new measurements of the $\ensuremath{\mu}\mathrm{s}$ half-lives of the odd-odd $^{126--130}\mathrm{In}$ are reported. However, the expected ${8}^{+}$ isomers in the even-mass Cd isotopes were not observed. The comparisons between the experimental $B(M2)$ strengths for In and Sn isotopes are discussed. A shell-model study of the heaviest In and Cd nuclei was performed using a realistic interaction derived from the CD-Bonn nucleon-nucleon potential. The calculation predicts values of the half-lives of the first ${8}^{+}$ states in $^{126,128}\mathrm{Cd}$ of $\ensuremath{\sim}10\phantom{\rule{0.3em}{0ex}}\mathrm{ns}$, which could explain the nonobservation of $\ensuremath{\mu}\mathrm{s}$ isomers. Comparison shows that the calculated levels of $^{130}\mathrm{In}$ and $^{129}\mathrm{In}$ are in good agreement with the experimental values while some discrepancies occur for the lighter In isotopes. The collectivity of $^{126,128}\mathrm{Cd}$ is discussed in the framework of the shell model and in comparison with $^{204}\mathrm{Hg}$.

A new ranging algorithm for frequency modulated/continuous wave (FM/CW) radars is given. This algorithm is near optimal, very robust, does not depend on the type of modulation, and is fairly easy to compute. An example of an older algorithm based on sinusoidal frequency modulation (FM) used on the MK-95 CW radar is given to illustrate shortcomings in typical older algorithms and for comparison purposes. The characteristics of the new ranging algorithm and test results from the MK-95 radar are provided. The actual target range and the one calculated using the new ranging algorithm differed by less than 1%.

The existing ternary fission models can well reproduce the yields of the most abundant light charged particles. However, these models tend to significantly overestimate the yields of ternary particles with an extreme N/Z ratio: {sup 3}He, {sup 11}Li, {sup 14}Be, etc. The experimental yields of these isotopes were investigated with the recoil separator LOHENGRIN down to a level of 10{sup {minus}10} per fission. Results from the fissioning systems {sup 233}U (n{sub th}, f), {sup 235}U(n{sub th},f), {sup 239}Pu(n{sub th},f) {sup 241}Pu(n{sub th},f) and {sup 245}Cm(n{sub th},f) are presented and the implications for the ternary fission models are discussed.

Stress-induced elevation of glucocorticoids is accompanied by structural changes and neuronal damage in certain brain areas. This includes reduced expression of brain-derived neurotrophic factor (BDNF) in the hippocampus which can be prevented by chronic electroconvulsive seizures and antidepressant drug treatment. In the last years we have bred two strains of rats, one which reacts with congenital helplessness to stress (cLH), and one which congenitally does not acquire helplessness when stressed (cNLH). After being selectively bred for more than 40 generations these strains have lost their behavioural plasticity including their sensitivity to antidepressant treatment. We show here that in cLH rats, acute immobilization stress does not induce a reduction of BDNF expression in the hippocampus which is observed in Sprague--Dawley and cNLH rats. All animals tested exhibited elevated corticosterone levels when stressed, an indication, that in cLH rats regulation of BDNF expression in the hippocampal formation is uncoupled from corticosterone increase induced through stress. This may explain the lack of adaptive responses in this strain.

During the reactor processing, fission products among which iodine are implanted by recoil inside the zircalloy cladding tube: most of them being distributed in the first 2 μm. At the same time oxidation of the cladding tube occurs, hence in the waste storage phase zirconia will act as a migration barrier. In order to determine diffusion data, stable and radioactive iodine atoms were introduce in zirconium oxidized samples by mean of ion implantation. Iodine thermal-release was measured either by Rutherford Backscattering Spectroscopy or γ spectroscopy. Two depths range were studied, the subsurface (

Considerable interest has been recently generated concerning the use of natural compounds, anti-oxidants in particular, in photoprotection. Two of the best known anti-oxidants are vitamins C and E, both of which have been shown to be somewhat effective in different models of photodamage. Very little has been reported, however, on the effectiveness of a combination of the two (known to be biologically the more relevant situation); nor have there been detailed studies on the ability of these antioxidants to augment commercial sunscreen protection against UV damage. We report that (in swine skin) vitamin C is capable of additive protection against acute UVB damage (sunburn cell formation) when combined with a UVB sunscreen. A combination of both vitamins E and C provided very good protection from a UVB insult, the bulk of the protection attributable to vitamin E. However, vitamin C is significantly better than vitamin E at protecting against a UVA-mediated phototoxic insult in this animal model, while the combination is only slightly more effective than vitamin C alone. When vitamin C or a combination of vitamin C and E is formulated with a commercial UVA sunscreen (oxybenzone), an apparently greater than additive protection is noted against the phototoxic damage. These results confirm the utility of anti-oxidants as photoprotectants but suggest the importance of combining the compounds with known sunscreens to maximize photoprotection.

This report summarizes work carried out during the period 1991-1995 in connection with the refinement of the concepts and detailed designs for nuclear and fundamental physics research instrumentation at the proposed Advanced Neutron source at Oak Ridge National Laboratory. Initially, emphasis was placed on refining the existing System Design Document (SDD-43) to detail more accurately the needs and interfaces of the instruments that are identified in the document. The conceptual designs of these instruments were also refined to reflect current thinking in the field of nuclear and fundamental physics. In particular, the on-line isotope separator (ISOL) facility design was reconsidered in the light of the development of interest in radioactive ion beams within the nuclear physics community. The second stage of this work was to define those instrument parameters that would interface directly with the reactor systems so that these parameters could be considered for the ISOL facility and particularly for its associated ion source. Since two of these options involved ion sources internal to the long slant beam tube, these were studied in detail. In addition, preliminary work was done to identify the needs for the target holder and changing facility to be located in the tangential through-tube. Becausemore » many of the planned nuclear and fundamental physics instruments have similar needs in terms of detection apparatus, some progress was also made in defining the parameters for these detectors. 21 refs., 32 figs., 2 tabs.« less

The study of fission yields has a major impact on the characterization and understanding of the fission process and is mandatory for reactor applications. While the yields are known for the major actinides ( 235 U, 239 Pu) in the thermal neutron-induced fission, only few measurements have been performed on 242 Am. The interest of 242 Am concerns the reduction of radiotoxicity of 241 Am in nuclear wastes using transmutation reactions. This paper presents the measurement of the fission mass yields from the reaction 241 Am(2nth,f) performed at the Lohengrin mass spectrometer (ILL, France) for both the light and the heavy peaks: a total of 41 mass yields have been measured. The experiment was also meant to determine whether there is a difference in mass yields between the isomeric state and the ground state as it exists in fission and capture cross sections. The method used to address this question is based on a repeated measurement of a set of fission mass yields as a function of the ratio between the 242g Am and the 242m Am fission rates. The presented experiment is also a first step towards the measurement of the isotopic fission yields of 242 Am .

We review the statistical model and its application for the process of nuclear fission. The expressions for excitation energy and spin distributions for the individual fission fragments are given. We will finally emphasize the importance of measuring prompt gamma decay to further test the statistical model in nuclear fission with the FIPPS project.

Projectile fission of 238U was investigated at a bombarding energy of 750 A·MeV using a Pb target. Forward emitted fragments from 80Zn up to 155Ce were analyzed with the Fragment Separator (FRS) and unambigously identified by their energy-loss and time-of-flight. The magnetic selection of the largest momenta acted as a trigger of the low-energy fission component. More than forty new nuclear species were identified. The related isotopic production cross-sections are presented.

The application of stable isotopes creates further possibilities for our understanding of the metabolism. New concepts especially for non-invasive diagnostic procedures could be developed. An important step in our research program was the performing of a 1-year experiment on a volunteer. On the basis of a 10-pool model we received a lot of informations. Based on this knowledge we developed 2 simplified methods for calculating whole body protein turnover. Knowing the problems with whole body protein calculations we intensified our intentions for determining the protein enrichment in organs and isolated cells (hepatocytes), estimating at the same time the precursor pool in the cells. Of special importance was an extensive study, wherein all those 15N-estimations were performed we are able to do up to now. We calculated whole body protein, but especially we studied the enrichment of the cellular protein fractions in hepatocytes, of plasmaproteins, and of the intracellular precursor pool. This study is the base for further tracer investigations.

As previously shown, purified 14S RNA of mouse myeloma MOPC-41 forms a single peak on sucrose gradients and gel electrophoresis and codes for a single polypeptide chain, the immunoglobulin light chain produced by the same myeloma in vivo . This 14S mRNA was used for the enzymatic synthesis of DNA (cDNA) which is complementary to the RNA template. A DNA fraction was isolated which has an average size of 300 nucleotides. Kinetic studies of the hybridization of the 14S RNA with the cDNA indicate that about 40% of the RNA consists of a single RNA sequence. From the size of the cDNA fraction and from the direction of DNA synthesis, it can be concluded that the cDNA includes the sequence complementary to the constant region of light chain mRNA. This radioactive cDNA was used for DNA·DNA reannealing experiments with unlabeled DNA from mouse liver or myeloma tumor in 3 × 10 6 -fold excess. This allowed the determination of the number of copies in the mouse genome of those sequences represented in the cDNA. The data show no significant reiteration in either liver or myeloma DNA and suggest that the gene coding for the constant part of immunoglobins is present in the haploid genome in one to five copies. Furthermore, this gene is not “amplified” in nuclear DNA of myeloma plasmocytes.

Die vorliegende Arbeit vergleicht den Einfluβ von zwei Aminosäurenlösungen auf den posttraumatischen Proteinstoffwechsel durch Bestimmung der Stickstoffbilanz, der 15N-Elimination, der Gesamt-körperproteinsynthese und der Verwertung des zugeführten Stick-stoffs unter Verwendung von Schweinen als Versuchstiere. Die Proteinsynthese und die Stickstoffverwertung wurden mit Hilfe der 15N-Tracertechnik bei Nutzung mathematischer Modellvorstellungen ermittelt. Die nicht operierten Kontrolltiere wiesen bei Infusion einer Lösung mit einem herkömmlichen Aminosäurenmuster (Lösung A) eine geringere Stickstoffausscheidung im Urin, eine günstigere Stickstoffbilanz, eine höhere 15N-Retention, eine bessere Gesamtkörper-proteinsynthese und Verwertung der infundierten Aminosäuren auf, verglichen mit den operierten Tieren, denen entweder Lösung A oder eine andere Aminosäurenlösung (Lösung B) verabreicht wurden. Die Gegenüberstellung der postoperativen Daten zeigt, daβ bei Vergleich der Lösung A mit Lösung B, deren Aminosäurenzusammensetzung den posttraumatisch veränderten Plasmaaminosäurenmetabolismus berücksichtigt, Lösung B die besseren Ergebnisse hinsichtlich der 15N-Retention, aber auch der Gesamtkörperproteinsynthese und der Stickstoffverwertung aufweist.

Es wird eine standardisierte 15N-Tracermethode für die Beurteilung des Stickstoff- bzw. Proteinstoffwechsels des gesunden und pathologisch veränderten Organismus beschrieben. Diese isotopentechnische Methode eignet sich für die Anwendung in der klinischen Forschung und Praxis. Sie umfaβt folgende Arbeitsschritte: die klinische Vorbereitung des Patienten/Probanden mit Hilfe eines standardisierten Ernährungsregimes, die Traceradministration (einmalig oral) und die Probensammlung (Urin, Blut), die 15N-Tracertechnik (Probenchemie, emissionsspektrometrische Isotopenanalyse) und die mathematische Auswertung der 15N-Tracerdaten.

Unter Anwendung des stabilen Isotops 15N wurde die Verwertung von Aminosäureninfusionslösung bei Gesunden und bei Patienten im Streß (Zustand nach Cholezystektomie) untersucht. Die Ergebnisse beziehen sich auf Infusionsgeschwindigkeit, Dosierung, Infusionslösung und Glyzin als Tracersubstanz. Es konnte nachgewiesen werden, daß Aminosäuren auch im Streß zur Eiweißsynthese herangezogen werden, wenn auch in geringerem Maße als bei Probanden in ausgeglichenem Stoffwechselzustand. Vom infundierten 15N verblieben 72 bis 77 % bei ausgeglichener Bilanz und 56 bis 58 % bei kataboler Stoffwechsellage im Organismus. Die Harnstoffbildung lief im Streß verstärkt und beschleunigt ab. Die gefundenen Werte passen gut zu den Resultaten früherer Zufuhr-Bilanz-Versuche an Patienten in verschiedenen Streßlagen. Sie gestatten Aussagen über die Effektivität der parenteralen Aminosäurenzufuhr im Streß.

The 'sump syndrome' is a rare, late complication of choledochoenterostomies. We observed 13 patients with this syndrome. The clinical features included recurrent cholangitis, liver abscesses, and recurrent pancreatitis. Five patients were treated by surgery, eight patients endoscopically. Reviewing an average follow up period of 22 months (range 6-60) after therapeutic endoscopy and 57 months (range 1-126) after different surgical procedures, we conclude that endoscopic sphincterotomy with removal of the debris is as efficient a therapy of the 'sump syndrome' as surgical sphincteroplasty and entails a smaller risk for the patient. We therefore advocate that endoscopic papillotomy should first be tried in all cases of 'sump syndrome' in the absence of suprapapillary stricture of the bile ducts.

Im Rahmen dieser Studie haben wir die Utilisation einmalig oral applizierten 15N-Glyzins an insgesamt 7 Patienten in der Rekonvaleszenz untersucht. In regelmäβigen Abständen wurden Gesamt-N, Harn-stoff-N und Ammoniak-N sowie deren relative 15N-Häufigkeit im Urin untersucht. Wir erhielten folgende Ergebnisse: Der Ammoniakpeak fand sich 25 Minuten früher als der Harnstoffgipfel. Die kumulative 15N-Aus-scheidung betrug nach 24 Stunden 25 % und nach 6 Tagen 34,4 % der Zufuhr. Nach 12 Stunden waren bereits 53 % der nach 6 Tagen insgesamt eliminierten Menge ausgeschieden. Der Anteil des Harn-stoff-15N am Gesamt-15N betrug 24 Stunden nach Applikation 80 %, der des Ammoniak-15N 2,8 %. Weiterhin konnten Korrelationen zwischen Stickstoffzufuhr minus -ausfuhr als Maβ der Bilanz und kumulativer Ausscheidung von 15N-Harnstoff nachgewiesen werden. Bei Negativierung der Bilanz erhöhten sich kumulative Ausscheidung sowie Anteil des Harnstoffs am Gesamtstickstoff und relative Elimination nach 12 Stunden gegenüber 144 Stunden. Daraus kann geschlossen werden, daβ sich bei kataboler Stoffwechsellage die Metabolisierung von Glyzin zu Harnstoff erhöht. Gleichzeitig wird dieser Prozeβ beschleunigt. Das gewählte Modell scheint geeignet, auf relativ einfache Weise einen Einblick in die Stoffwechselsituation zu erhalten.