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Micro and nano systems (MNS) and Nano scaled devices, that are capable of handling fluids and to interact with DNA and proteins enable bio analysis at the “ultimate” molecular level and are prone to be coupled to IC Technology. This paper includes recent developments in this area, aimed at illustrating the diversity and potential of the MNS approach: (1) micromachined tweezers with sharp tips successfully captured a bundle of DNA molecules, allowing real-time observation of DNA degradation dynamics under therapeutic irradiations; (2) a simple method to fabricate FET silicon nanowires using only standard micro-electromechanical system (MEMS) processes is able to perform molecular level medical diagnosis; (3) a bio motor system, composed by microtubules and kinesin, reconstructed on a chip, can distinguish normal and abnormal tau-proteins related to Alzheimer’s disease; and (4) an advanced concept of molecular programing in which real molecular interactions emulate partial different equations and are able to solve complex systems such as a predator–prey ecosystem. [ABSTRACT FROM AUTHOR]

Abstract: The gamma-ray activity from short-lived fission products has been measured in fresh and burnt UO2 fuel samples after irradiation in a zero-power reactor. For the first time, short-lived gamma-ray activity from fresh and burnt fuel has been compared and fresh-to-burnt fuel fission rate ratios have been derived. For the measurements, well characterized fresh and burnt fuel samples, with burn-ups up to 46GWd/t, were irradiated in the zero-power research reactor PROTEUS. Fission rate ratios were derived based on the counting of high-energy gamma-rays above 2200keV, in order to discriminate against the high intrinsic activity of the burnt fuel. This paper presents the measured fresh-to-burnt fuel fission rate ratios based on the 142La (2542keV), 89Rb (2570keV), 138Cs (2640keV) and 95Y (3576keV) high-energy gamma-ray lines. Comparisons are made with the results of Monte Carlo modeling of the experimental configuration, carried out using the MCNPX code. The measured fission rate ratios have 1σ uncertainties of 1.7–3.4%. The comparisons with calculated predictions show an agreement within 1–3σ, although there appears to be a slight bias (∼3%). [Copyright &y& Elsevier]

Abstract: This paper presents the vortex dynamics generated by the interaction of a submerged horizontal plate, considered as a vortex generator, and a monochromatic wave. The velocity and vorticity fields are determined experimentally using PIV technique for different resolutions in order to study the global flow around the plate and the formation and advection of vortices upstream and downstream of the plate. The global flow around the plate shows great discrepancies with the potential flow solution: two recirculation cells are formed beneath the plate, the global flow is non-symmetric and the advection of vortices induces strong velocities not represented by the potential flow theory. The formation of vortices at the edges of the plate is characterised. At each period, one vortex is formed at the edge followed by the formation of an opposite sign vortex. The upstream and downstream vortex pairs are then advected in front of the plate and toward the bottom respectively, over a distance of about one third the plate length. The lifetime of vortices is about two wave periods. This study will help us validate a numerical software to be used for analysing the influence of various parameters on the dynamics. These results will be presented in the second part of this paper. [Copyright &y& Elsevier]

Abstract: A boiling water reactor SVEA-96+ fresh fuel lattice has been used as the basis for a benchmark study of the void reactivity coefficient at assembly level in the full voidage range. Results have been obtained using the deterministic codes CASMO-4, HELIOS, PHOENIX, BOXER and the probabilistic code MCNP4C, combined for almost all cases with different cross section libraries. A statistical analysis of the results obtained showed that the void reactivity coefficient tends to become less negative beyond 80% void and that the discrepancies between codes tend to increase from less than 15% at voidages lower than 40% to more than 25% at voidages higher than 70%. The void reactivity coefficient results and the corresponding differences between codes were isotopically decomposed to interpret discrepancies. The isotopic decomposition shows that the minimum observed in the void reactivity coefficient between 80% and 90% void is largely due to the decrease in the relative importance of the 157Gd(n,γ) rate with increasing voidage, and that the fundamental discrepancies between codes or libraries are mainly governed by the different predictions of the 238U(n,γ) variation with voidage. [Copyright &y& Elsevier]

Abstract: Characterisation of the SVEA-96 Optima2 boiling water reactor assembly, in terms of the radial distributions of normalised total fission and 238U capture rates, is reported at its central elevation, i.e. at the 92-pin section, where the one-third part-length pins are replaced by water. Measurements performed in the PROTEUS facility are compared with MCNPX predictions. The calculation model included the measured locations of the SVEA-96 Optima2 assemblies and sub-assemblies, within the PROTEUS test zone. Predicted and experimental fission and 238U capture rates are found to agree, respectively, within 3.5% and 4% for all pins. Fission rates in the burnable-absorber UO2–Gd2O3 fuel pins have been predicted without bias using the ENDF/B-VI data library but show an average 1.4% under-prediction with the JEFF-3.1 data library. A slight overestimation of the total fission rate in the pins located at the periphery of the assemblies was observed and has been attributed to an inaccurate modelling of the pin positions. However, there was no systematic bias observed due to the absence of the one-third pins at the corners of the assembly. [Copyright &y& Elsevier]

In this paper we are proposing a re-evaluation of the thermal-neutron induced capture cross section of 147 Nd. A unique measurement exists from which this cross section was calculated in 1974. This original calculation is based on an assumed value for a specific gamma-ray fraction (called F 2 ), taken from the neighboring nucleus 145 Nd. With the availability of reaction codes such as TALYS, such fraction can nowadays be calculated using specific reaction models and parameters. The new value of F 2 indicates a decrease of the thermal cross section by 45%, leading to 243 barns, instead of the 440 barns previously reported. This new cross section impacts the calculation of the number density for the well-known burn-up indicator 148 Nd, but as shown, the change is close to the usual experimental uncertainties for the 148 Nd number densities, thus having a limited impact on burn-up calculation. [ABSTRACT FROM AUTHOR]

Duchenne muscular dystrophy (DMD) is a rare, progressive, lethal, X-linked disease due to mutations in the dystrophin gene. GNT0004 is a serotype 8 adeno-associated virus (AAV8) vector-based gene therapy containing a shortened functional version of DMD gene (hMD1). Driven by a Spc5.11 promotor, the hMD1targets expression in skeletal and cardiac muscle. GNT0004 is currently being evaluated in an all-in-one clinical trial. The data here are from first in human and dose escalation part of our trial. Upon dose-selection, transition to a placebo-controlled pivotal part is planned. Ambulant DMD boys aged 6 to 10 years, with stable or in the decline phase of the motor score were enrolled. Subjects had a stable baseline steroids for ≥ 6 months and received a short term of prophylaxis with sirolimus and add-on steroids. hMD1 expression were measured before and 8 weeks after GNT0004 dosing (biceps brachii biopsies). To date, 2 and 3 patients received dose 1 (1E13vg/kg) and dose 2 (3E13vg/kg) respectively. Post dosing, mean hMD1 positive fibers was 1.96% with dose 1 and 53% with Dose 2. Vector Copy Number per nuclei (VCN) was 0.4-2.5 (mean 1.2) with Dose 2. A decrease in serum CK of 50%-87% from baseline to week 16 was seen with Dose 2. Overall, GNT0004 was well tolerated in all subjects receiving sirolimus and steroid prophylaxis (implemented after SUSAR event of immune-mediated myositis that occurred in 1st patient with dose 1). Five Adverse Drug Reactions were reported, including SUSAR case (dystrophin epitope-naive patient at risk of immunological complications, this subset population subsequently excluded from the trial) and 4 mild events. GNT0004 dose 2 provided significant transduction and transgene expression in skeletal muscles in DMD boys with early sign of the sarcolemma stabilization and clinical benefit. Overall, GNT0004 was well tolerated in 4 patients to date and longer follow-up data are being collected to assess long-term safety and the clinical effectiveness. [ABSTRACT FROM AUTHOR]

BACKGROUND: In stage III colorectal cancer (CRC), adjuvant chemotherapy (CT) is usually prescribed within two months after curative surgery. Whether or not delaying initiation of CT affects survival is still debated. MATERIAL AND METHODS: We performed a meta-analysis (MA) of all published studies (full papers or abstracts) comparing delayed CT with standard care. Studies were obtained from a PubMed query (keywords: CRC, adjuvant treatment, delay of CT), a review (Chau et al., 2006), cross-checking references and abstracts from the proceedings of ASCO, ASCO GI and WCGI annual meetings. We chose a cutoff delay of 8 weeks. Risk Ratios (RRs) were calculated from the recorded events (deaths, relapses). We used EasyMA software (fixed-effect model). RESULTS: Fourteen studies (including four abstracts) were identified (17,645 patients; 5,952 males, 5,151 females, mean age 70 years). Of these, three could not be statistically analysed and three used another cutoff (4, 5 or 6 weeks), leaving 8 studies for main MA (13,158 patients; 3,932 males, 3,644 females, 5,942 missing data; 5,576 colon cancers, 6,677 rectal, 1,265 missing data). Delaying CT more than 8 weeks was associated to worse Overall Survival (OS) (RR: 1.20; 95% Confidence Interval (CI) 1.15-1.26). In the MA including all studies whatever their cutoff, longer delay was similarly associated to a worse OS but not a worse Relapse-Free Survival (RFS) (five studies). CONCLUSION: Adjuvant chemotherapy should be started within 8 weeks after surgery. Delaying the initiation of adjuvant CT for more than 8 weeks after surgery significantly decreased OS but not RFS. This discrepancy might be due to factors not directly related to cancer (post-operative complications, social status) or to a more accurate appraisal of death. [ABSTRACT FROM AUTHOR]

Abstract: As part of a joint research programme between the Paul Scherrer Institute (PSI) and swissnuclear, with the co-operation of the Leibstadt nuclear power plant in Switzerland and fuel suppliers Westinghouse Sweden, measurements and calculations have been made of the axial and radial distributions of fission and 238U capture rates in the fuel rods of a Westinghouse SVEA-96 Optima2 boiling water reactor assembly. The measurements, made in the zero-energy research reactor PROTEUS at PSI, have been compared with calculations carried out using the Monte Carlo code MCNPX. The results reported are for the regions near the ends of the part-length fuel rods, which are a feature of SVEA-96 Optima2 assemblies. The sudden increase in moderation above the ends of the part-length rods leads to power peaking in the adjacent rods. Careful attention needs to be given to this phenomenon in the deployment of such fuel, the present paper providing experimental evidence for the ability of a stochastic code to predict such effects. [Copyright &y& Elsevier]

Abstract: The incidence of sudden death due to undiagnosed primary intracranial tumor is low in forensic autopsy. We report a case of a 48-year-old white male, known to be a schizophrenic patient for several years, and in whom a medico-legal autopsy disclosed a large, previously undiagnosed, bilateral frontal glioblastoma infiltrating the genu of corpus callosum. We emphasize the importance of performing complete autopsy, including a thorough neuropathological examination, in all cases of sudden unexpected death, especially in those cases in which no extracerebral cause of death had been established and whose clinical history was primarily of a psychiatric nature. [Copyright &y& Elsevier]

Nuclear data uncertainty propagation plays a growing role in neutronic simulation by giving confidence bounds to physical macroscopic parameters used for safety and design of nuclear systems. This study deals with nuclear data uncertainty propagation (cross-sections, fission spectrum, neutron multiplicities and fission yields) on the nuclide composition of two UO 2 spent fuel samples of different burnup. In order to perturb the fission yields in a neutron lattice physics code, the perturbation methodology combines an external correlation matrix to the standard deviations available in the international evaluations. The resulting matrix is normalized to fit to physical constraints. Then the impacts of nuclear data uncertainties on the k-inf are assessed and the main contributors are highlighted. Two different sources of uncertainty for the cross-sections and the fission yields are compared showing the large effect of the input uncertainty. The actinides and fission products composition of the two samples after depletion are sorted according to the main uncertainty origin of their C/E (experimental, cross-sections, fission yields). Special attention is paid to the Nd-148 C/E comparisons as these results show the need for improvement of the Nd-147 capture uncertainties. [ABSTRACT FROM AUTHOR]

Abstract: The recent experimental programme conducted in the PROTEUS research reactor at the Paul Scherrer Institute (PSI) has concerned detailed investigations of advanced light water reactor (LWR) fuels. More than fifteen different configurations of the multi-zone critical facility have been studied, each of them requiring accurate estimation of operational safety parameters, in particular the critical driver loadings, shutdown rod worths and the effective delayed neutron fraction βeff . The current paper presents a full-scale 3D Monte Carlo model for the facility, set up using the MCNPX code, which has been employed for calculation of the operational characteristics for seven different LWR-PROTEUS configurations. Thereby, a variety of nuclear data libraries (viz. ENDF/B6v2, ENDF/B6v8, JEF2.2, JEFF3.0, JEFF3.1, JENDL3.2, and JENDL3.3) have been used, and predictions of keff and shutdown rod worths compared with experimental values. Even though certain library-specific trends have been observed, the keff predictions are generally very satisfactory, viz. with discrepancies of <0.5% between calculation (C) and experiment (E). The results also confirm the consistent determination of reactivity variations, the C/E values for the shutdown (safety) rod worths being always within 5% of unity. In addition, the MCNP modelling of the multi-zone reactor has yielded interesting results for the delayed neutron fraction (βeff ) in the different configurations, a breakdown being made possible in each case in terms of delayed neutron group, fissioning nuclide, and reactor region. [Copyright &y& Elsevier]