Leading-order nucleon self-energy in relativistic chiral effective field theory

We apply thermal field theory methods to compute microscopically the nucleon self-energy arising from one-pion exchange in isospin-symmetric nuclear matter and neutron matter. A self-consistent numerical scheme is introduced and its convergence is demonstrated. The repulsive contribution from the Fock exchange diagram to the energy per nucleon in symmetric nuclear matter is obtained.Comment: v3: matches published version, 8 pages, 6 figures. Removed discussion of saturation, changed title to reflect the shortened content. v1: 9 pages, 7 figures, v2: minor amendment

Chiral pions in a magnetic background

We investigate the modification of the pion self-energy at finite temperature due to its interaction with a low-density, isospin-symmetric nuclear medium embedded in a constant magnetic background. To one loop, for fixed temperature and density, we find that the pion effective mass increases with the magnetic field. For the $\pi^{-}$, interestingly, this happens solely due to the trivial Landau quantization shift $\sim |eB|$, since the real part of the self-energy is negative in this case. In a scenario in which other charged particle species are present and undergo an analogous trivial shift, the relevant behavior of the effective mass might be determined essentially by the real part of the self-energy. In this case, we find that the pion mass decreases by $\sim 10$ for a magnetic field $|eB|\sim m_\pi^2$, which favors pion condensation at high density and low temperatures.Comment: 7 pages, 5 figure

Rotating hybrid compact stars

Starting from equations of state of nucleonic and color-superconducting quark matter and assuming a first-order phase transition between these, we construct an equation of state of stellar matter, which contains three phases: a nucleonic phase, as well as two-flavor and three-flavor color-superconducting phases of quarks. Static sequences of the corresponding hybrid stars include massive members with masses of $\sim 2 M_{\odot}$ and radii in the range of $13< R < 16$ km. We investigate the integral parameters of rapidly rotating stars and obtain evolutionary sequences that correspond to constant rest-mass stars spinning down by electromagnetic and gravitational radiation. Physically new transitional sequences are revealed that are distinguished by a phase transition from nucleonic to color-superconducting matter for some configurations that are located between the static and Keplerian limits. The snapshots of internal structure of the star, displaying the growth or shrinkage of superconducting volume as the star's spin changes, are displayed for constant rest mass stars. We further obtain evolutionary sequences of rotating supramassive compact stars and construct pre-collapse models that can be used as initial data to simulate a collapse of color-superconducting hybrid stars to a black hole.Comment: 9 pages, 9 figures; v2: minor improvements, matches published version, v3: corrected figure placemen

Effect of acceleration forces during transport through a pneumatic tube system on ROTEM® analysis

Background: ROTEM® is considered a helpful point-of-care device to monitor blood coagulation in emergency situations. Centrally performed analysis is desirable but rapid transport of blood samples is an important prerequisite. The effect of acceleration forces on sample transport through a pneumatic tube system on ROTEM® should be tested at each institution to exclude a pre-analytical influence. The aims of the present work were: (i) to investigate the effect of pneumatic tube transport on ROTEM® parameters; (ii) to compare blood sample transport via pneumatic tube vs. manual transportation; and (iii) to determine the effect of acceleration forces on ROTEM® parameters. Methods: This is a single centre study with 20 healthy volunteers. Five whole blood samples were transferred to the central haematology laboratory by either normal transport or pneumatic delivery with different speed and acceleration forces. EXTEM, INTEM, FIBTEM and APTEM were analysed in parallel with two ROTEM® devices and compared. Acceleration forces were measured during transport with two different instruments. Results: Increment of transport time, speed and distance resulted in an augmentation of acceleration forces and peaks. All results of the ROTEM® analysis after manual transport or pneumatic delivery were within normal range. However, increase in acceleration forces resulted in minimally but statistically significant changes in multiple ROTEM® parameters. The higher the acceleration forces, the more ROTEM® parameters are influenced. Conclusions: Acceleration forces during transport through a pneumatic tube system have an influence on ROTEM® parameters. Prior to transfer blood samples via pneumatic tube system these influences should be tested to exclude clinically relevant blood coagulation activation in vitr

Psychology and Sustainability, Homo Technicusand Slow Tech

Psychology and Sustainability, Homo Technicus and Slow TechIn previous issues of Visions for Sustainabilitywe have often published papers that consider the relationship between psychology and sustainability. On the one hand, researchers have examined various aspects of the incompatibility between how human societies and individuals behave in order to satisfy their needs and their desires and the natural processes that are essential for maintaining ecological balance and integrity, both for the people themselves and the environments they inhabit. Problems of sustainability are clearly related to human behaviours and therefore are a part of the psychological sphere. Studies have often focused on examining ways of promoting pro-environmental and reducing anti-environmental behaviours

Founder mutations in BRCA1 and BRCA2 genes

BRCA1 and BRCA2 germline mutations contribute to a significant number of familial and hereditary breast and/or ovarian cancers. The proportion of high-risk families with breast and/or ovarian cancer cases due to mutations in these tumor suppressor genes varies widely among populations. In some population, a wide spectrum of different mutations in both genes are present, whereas in other groups specific mutations in BRCA1 and BRCA2 have been reported with high frequency. Most of these mutations are prevalent in restricted populations as consequence of a founder effect. The comparison of haplotypes between families with the same mutation can distinguish whether high-frequency alleles derive from an older or more recent single mutational event or whether they have arisen independently more than once. Here, we review some of the most well-known and significant examples of founder mutations in BRCA genes found in European and non-European populations. In conclusion, the identification of the ethnic group of families undergoing genetic counseling enables the geneticist and oncologist to make more specific choices, leading to simplify the clinical approach to genetic testing carried out on members of high-risk families. Futhermore, the high frequency of founder mutations, allowing to analyze a large number of cases, might provide accurate information regarding their penetrance

micro-LIBS vs. XRF analysis of surface-enriched silver coins. Is a micro-destructive approach really unavoidable?

We have performed a comparative study of micro-LIBS and X-Ray Fluorescence Spectroscopy (XRF) analysis for quantifying the silver contents in Swabian deniers minted during the Kingdom of Sicily (1194-1266). The combined use of the two techniques allowed us to validate the chemical composition of the coins and to valuate the altered surface and the surface-enrichment treatment eventually undergone. The use of LIBS coupled with microscope allowed to reduce the dimen- sion of the laser-induced crater below 20μm so the visual aspect of the coin remains unchanged. The LIBS measures over- come the question of the surface alteration, but they do not represent the heterogeneity of the alloy because of the small sampling area. On the other hand, the XRF technique allows to analyze a larger surface, in a totally non destructive way; however, the sampling volume could be affected by alterations or excessive roughness. It has been verified that these two factors do not affect the reliability of the measures but could introduce an uncertainty in the quantity data. The LIBS quanti- tative data have been obtained using the One Point Calibration method (OPC) while the XRF quantitative data were ob- tained by means of the Fundamental Parameter method. A good agreement between the two results was found, demonstrat- ing the effectiveness of both the micro-LIBS and XRF techniques, in spite of the above mentioned limitations. The compara- tive study has been conducted on a group of 50 deniers belonging to the reign of Henry VI and Frederick II; the results con- firmed the knowledge about the devaluations of the coins within 50 years of the Swabian Kingdom. A classification method has been proposed to set historically the coins