Using bijective maps to improve free energy estimates

We derive a fluctuation theorem for generalized work distributions, related to bijective mappings of the phase spaces of two physical systems, and use it to derive a two-sided constraint maximum likelihood estimator of their free energy difference which uses samples from the equilibrium configurations of both systems. As an application, we evaluate the chemical potential of a dense Lennard-Jones fluid and study the construction and performance of suitable maps.Comment: 17 pages, 11 figure

Breast cancer: Monitoring response to neoadjuvant chemotherapy using Tc-99m sestamibi scintimammography

Background: Aim of the study was to assess the value of scintimammography using Tc-99m sestamibi in the evaluation of tumor response to neoadjuvant chemotherapy. Material and Methods: Results were calculated for 9 patients undergoing neoadjuvant chemotherapy. Scintimammography using 740 MBq Tc-99m sestamibi was performed before, during and after chemotherapy, and sestamibi uptake was scored visually and semiquantitatively to evaluate tumor response. Results: In the case of complete response (n = 3) sestamibi uptake decreased 8 days after beginning neoadjuvant chemotherapy and normalized in the following course. Focal uptake decreased more slowly in patients with partial response (n = 3), who showed clear, persisting tracer accumulation after therapy. The patients without response (n = 3) showed a persisting high tumor activity even after chemotherapy was completed. Conclusions: The preliminary data suggest that in contrast to other imaging modalities scintimammography appears to yield early information regarding tumor response to neoadjuvant chemotherapy

The effect of N fertilizer placement, formulation, timing, and rate on the agronomic performance in wheat

Non-Peer ReviewedIncreasing the efficiency of nitrogen fertilizer uptake by crops improves the agronomic, economic, and environmental value of fertilizer N. Band placement of urea below the soil surface increased recovery of N in plants in both conventional and no-tillage systems. The latter systems require all fertilizers be applied before or during the seeding operation. In order to avoid seedling damage caused by fertilizer, side banding and mid-row banding opener systems have been developed to separate the seed and fertilizer. The objective of this study was to compare the agronomic performance in wheat between side banding and mid-row banding N fertilization and estimate effects of fertilizer formulation, timing and rate in an Orthic Brown Chernozem. A three-year experiment (2000-2002) was conducted near Swift Current in the Brown Soil Zone (Swinton silt loam, Orthic Brown Chernozem) of southern Saskatchewan. Seventeen treatments were arranged in a randomized complete block design in four replications with plot size of 3 m × 9.2 m. A Canada Western Red Spring wheat, AC Barrie, was seeded on a no-tillage management. Results showed that the environment had a major impact on the grain yield and biomass production. In general, the difference in agronomic performance between side banding and mid-row banding treatments was small

EDGE: a code to calculate diffusion of cosmic-ray electrons and their gamma-ray emission

The positron excess measured by PAMELA and AMS can only be explained if there is one or several sources injecting them. Moreover, at the highest energies, it requires the presence of nearby ($\sim$hundreds of parsecs) and middle age (maximum of $\sim$hundreds of kyr) source. Pulsars, as factories of electrons and positrons, are one of the proposed candidates to explain the origin of this excess. To calculate the contribution of these sources to the electron and positron flux at the Earth, we developed EDGE (Electron Diffusion and Gamma rays to the Earth), a code to treat diffusion of electrons and compute their diffusion from a central source with a flexible injection spectrum. We can derive the source's gamma-ray spectrum, spatial extension, the all-electron density in space and the electron and positron flux reaching the Earth. We present in this contribution the fundamentals of the code and study how different parameters affect the gamma-ray spectrum of a source and the electron flux measured at the Earth.Comment: Presented at the 35th International Cosmic Ray Conference (ICRC2017), Bexco, Busan, Kore