Sensitivity Analysis and Cross Sections Data Adjustment for Multigroup Transport and Diffusion

Uncertainties in basic nuclear data and other quantities involved in the characterization of an experiment affect the accuracy of the results when the respective experiment is modelled. The impact of these uncertainties on computed responses can be assessed by combining the sensitivities of these responses to the input parameters with data uncertainties and covariances. Furthermore, best estimates of both the input parameters and recomputed responses, with reduced uncertainties, can be obtained by using data assimilation and adjustment procedures. This paper reports the results of using the data adjustment methodology in conjunction with the well-known Godiva experiment and a partial set of uncertainties from the ZZ-COV-15 library for U-235 and U-238, together with sensitivities computed with APOLLO transport code by the Adjoint Sensitivity Analysis Procedure, to obtain best-estimate values for the k eigenvalue of the system, with reduced uncertainties. In parallel, sensitivities were also computed using COBAYA diffusion code, compared with those produced by APOLLO, and then employed in the adjustment formalism to obtain the adjusted k eigenvalue and its corresponding reduced uncertainty

Application of strategies for particulate matter reduction in urban areas: an italian case

The paper describes the particulate matter pollution in a Northern Italian city: Varese. The city is distinguished by a particular orographic and meteorological situation, characterized by valleys and heavy rainfalls. Nevertheless the urban area is interested by particulate matter pollution mainly due to heating systems and traffic. Here some corrective strategies in order to reduce PM air pollution have been presented, applied and evaluated by the means of a simplified model which considers emissions and meteorological conditions

Constrained von Neumann inequalities

An equivalent formulation of the von Neumann inequality states that the backward shift $S^*$ on $\ell_{2}$ is extremal, in the sense that if $T$ is a Hilbert space contraction, then $\|p(T)\| \leq \|p(S^*)\|$ for each polynomial $p$. We discuss several results of the following type : if $T$ is a Hilbert space contraction satisfying some constraints, then $S^*$ restricted to a suitable invariant subspace is an extremal operator. Several operator radii are used instead of the operator norm. Applications to inequalities of coefficients of rational functions positive on the torus are given.Comment: Preprint versio

Computed Tomography Imaging of Primary Lung Cancer in Mice Using a Liposomal-Iodinated Contrast Agent

To investigate the utility of a liposomal-iodinated nanoparticle contrast agent and computed tomography (CT) imaging for characterization of primary nodules in genetically engineered mouse models of non-small cell lung cancer.Primary lung cancers with mutations in K-ras alone (Kras(LA1)) or in combination with p53 (LSL-Kras(G12D);p53(FL/FL)) were generated. A liposomal-iodine contrast agent containing 120 mg Iodine/mL was administered systemically at a dose of 16 µl/gm body weight. Longitudinal micro-CT imaging with cardio-respiratory gating was performed pre-contrast and at 0 hr, day 3, and day 7 post-contrast administration. CT-derived nodule sizes were used to assess tumor growth. Signal attenuation was measured in individual nodules to study dynamic enhancement of lung nodules.A good correlation was seen between volume and diameter-based assessment of nodules (R(2)>0.8) for both lung cancer models. The LSL-Kras(G12D);p53(FL/FL) model showed rapid growth as demonstrated by systemically higher volume changes compared to the lung nodules in Kras(LA1) mice (p<0.05). Early phase imaging using the nanoparticle contrast agent enabled visualization of nodule blood supply. Delayed-phase imaging demonstrated significant differential signal enhancement in the lung nodules of LSL-Kras(G12D);p53(FL/FL) mice compared to nodules in Kras(LA1) mice (p<0.05) indicating higher uptake and accumulation of the nanoparticle contrast agent in rapidly growing nodules.The nanoparticle iodinated contrast agent enabled visualization of blood supply to the nodules during the early-phase imaging. Delayed-phase imaging enabled characterization of slow growing and rapidly growing nodules based on signal enhancement. The use of this agent could facilitate early detection and diagnosis of pulmonary lesions as well as have implications on treatment response and monitoring

Primary and secondary prevention to effectively reduce the risk of bisphosphonate-related osteonecrosis of the jaw in patients with bone metastases .

Background Bone is one of the most frequent sites of metastasis in patients with advanced cancer. Nearly all patients with myeloma, 65–75% of patients with prostate or breast cancer, and 30–40% of patients with lung cancer or other solid tumors, eventually develop bone metastases. Bisphosphonates (BP), particularly zoledronic acid and denosumab, were demonstrated to effectively reduce skeletal complications in patients with bone metastases. However, bisphosphonate-related osteonecrosis of the jaw (BRONJ) can occur spontaneously, favored by dental extraction, dental implant surgery, or denture wearing. The purpose of this study was to underline the role of dental prevention as an effective tool to reduce the risk of BRONJ. Material and methods BRONJ was identified with the standardized query “osteonecrosis” among all data from patients treated at Modena Cancer Center from 2005 to 2016. For each case, demographic and medical information were analyzed, as well as data about notification (year of occurrence, outcome), type and duration of BP exposure, and associated risk factors (dento-alveolar surgery, chemotherapy, antiangiogenics). Data were differently analyzed taking into account the implementation of a Dental Prevention Service in patients who are candidates for BP therapy.Results Among 1663 patients treated with BP, 63 cases of BRONJ were identified (3.8%). 44 female and 19 men with a median age of 69 years (range 47-90 years), have been treated with BP for bone metastases from breast cancer (54%), hematologic malignancy (21%), prostate cancer (13%), renal cancer (5%), lung cancer (2%) and other tumors (5%). 15 maxillae and 48 mandibles were involved. The trigger event was a dental extraction in 29% of the cases, being spontaneously the other 71%. The median time to BRONJ was 28 months (range 1-89.1 months) from the first dose of BP, and 25 was the mean number of BP doses administered before BRONJ. Overall, a preliminary odontoiatric evaluation was performed in only 14 cases (22%). All but one of these dentistry opinions were obtained after 2010 when the Dental Prevention Service was created, which is a drop out of the risk of BRONJ from 4.1 to 1.9%. Conclusions. Prevention of the BRONJ is critical in in bone metastatic patients. The incidence of BRONJ over time can drop to 1.9% when primary and secondary prevention measures are implemented in routine clinical practice

In Vivo Time- Resolved Microtomography Reveals the Mechanics of the Blowfly Flight Motor

Dipteran flies are amongst the smallest and most agile of flying animals. Their wings are driven indirectly by large power muscles, which cause cyclical deformations of the thorax that are amplified through the intricate wing hinge. Asymmetric flight manoeuvres are controlled by 13 pairs of steering muscles acting directly on the wing articulations. Collectively the steering muscles account for <3% of total flight muscle mass, raising the question of how they can modulate the vastly greater output of the power muscles during manoeuvres. Here we present the results of a synchrotron-based study performing micrometre-resolution, time-resolved microtomography on the 145 Hz wingbeat of blowflies. These data represent the first four-dimensional visualizations of an organism's internal movements on sub-millisecond and micrometre scales. This technique allows us to visualize and measure the three-dimensional movements of five of the largest steering muscles, and to place these in the context of the deforming thoracic mechanism that the muscles actuate. Our visualizations show that the steering muscles operate through a diverse range of nonlinear mechanisms, revealing several unexpected features that could not have been identified using any other technique. The tendons of some steering muscles buckle on every wingbeat to accommodate high amplitude movements of the wing hinge. Other steering muscles absorb kinetic energy from an oscillating control linkage, which rotates at low wingbeat amplitude but translates at high wingbeat amplitude. Kinetic energy is distributed differently in these two modes of oscillation, which may play a role in asymmetric power management during flight control. Structural flexibility is known to be important to the aerodynamic efficiency of insect wings, and to the function of their indirect power muscles. We show that it is integral also to the operation of the steering muscles, and so to the functional flexibility of the insect flight motor