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Rapid r-process nucleosynthesis is responsible for the creation of about half of the elements heavier than iron. Neutron capture on shortlived nuclei in cold processes or during freeze out from hot processes can have a significant impact on the final observed r-process abundances. We are validating the (d,pγ) reaction as a surrogate for neutron capture with measurements on 95Mo targets and a focus on discrete transitions. The experimental results have been analyzed within the Hauser-Feshbach approach with non-elastic breakup of the deuteron providing a neutron to be captured. Preliminary results support the (d,pγ) reaction as a valid surrogate for neutron capture. We are poised to measure the (d,pγ) reaction in inverse kinematics with unstable beams following the development of the experimental techniques.

To determine the safety of using argon as a deuteron beam stopping material, the  40Ar(d,p)41Ar cross section was measured at average deuteron energies of 3.6 MeV, 5.5 MeV, and 7.0 MeV using an activation method. A 16-MeV deuteron beam produced by Lawrence Berkeley National Laboratory's 88-Inch Cyclotron was degraded to each energy by nickel foils and the front wall of an aluminum gas chamber. The reduced-energy deuterons were used to activate a sample of natAr gas. After each irradiation, the gas chamber's  41Ar activation was measured with a high-purity germanium detector. The cross sections measured were larger than a previous measurement by ∼40%.

Neutron capture on unstable nuclei is important in understanding abundances in r-process nucleosynthesis. Previously, the non-elastic breakup of the deuteron in the (d,p) reaction has been shown to provide a neutron that can be captured by the nucleus and the gamma-ray decay of the subsequent compound nucleus can be modelled to predict the gamma-ray decay of the compound nucleus in the (n,γ) reaction. Preliminary results from the 95Mo(d,pγ) reaction in normal kinematics support the (d,pγ) reaction as a valid surrogate for neutron capture. The techniques to measure the (d,pγ) reaction in inverse kinematics have been developed.

Abstract Local adaptations to the environment are an important aspect of the diversity of a species and their discovery, description and quantification has important implications for the fields of taxonomy, evolutionary and conservation biology. In this study, we scan genomes from several populations across the distributional range of the Eurasian lynx, with the objective of finding genomic windows under positive selection which may underlie local adaptations to different environments. A total of 394 genomic windows are found to be associated to local environmental conditions, and they are enriched for genes involved in metabolism, behaviour, synaptic organization and neural development. Adaptive genetic structure, reconstructed from SNPs in candidate windows, is considerably different than the neutral genetic structure of the species. A widespread adaptively homogeneous group is recovered occupying areas of harsher snow and temperature climatic conditions in the north‐western, central and eastern parts of the distribution. Adaptively divergent populations are recovered in the westernmost part of the range, especially within the Baltic population, but also predicted for different patches in the western and southern part of the range, associated with different snow and temperature regimes. Adaptive differentiation driven by climate does not correlate much with the subspecies taxonomic delimitations, suggesting that subspecific divergences are mostly driven by neutral processes of genetic drift and gene flow. Our results will aid the selection of source populations for assisted gene flow or genetic rescue programs by identifying what climatic patterns to look for as predictors of pre‐adaptation of individuals. Particularly, the Carpathian population is confirmed as the best source of individuals for the genetic rescue of the endangered, isolated and genetically eroded Balkan population. Additionally, reintroductions in central and western Europe, currently based mostly on Carpathian lynxes, could consider the Baltic population as an additional source to increase adaptive variation and likely improve adaptation to their milder climate.

The r-process is responsible for creating roughly half of the elements heavier than iron. It has recently become understood that the rates at which neutron capture reactions proceed at late times in the r-process may dramatically affect the final abundance pattern. However, direct measurements of neutron capture reaction rates on exotic nuclei are exceptionally difficult, necessitating the development of indirect approaches such as the surrogate technique. The (d,pγ) reaction at low energies was identified as a promising surrogate for the (n,γ) reaction, as both reactions share many characteristics. We report on a program to validate (d,pγ) as a surrogate for (n,γ) using 95Mo as a target. The experimental campaign includes direct measurements of the γ-ray intensities from the decay of excited states populated in the 95Mo(n,γ) and 95Mo(d,pγ) reactions.

The study of the collective properties of nuclear excitations far from stability provides information about the shell structure at extreme conditions. Spectroscopic observables such as the energy or the transition probabilities of the lowest states, in nuclei with large neutron excess, allow to probe the density and isospin dependence of the effective interaction. Indeed, it was recently shown that tensor and three-body forces play an important role in breaking and creating magic numbers. Emblematic is the case of the evolution of the Ni isotopic chain where several features showed up moving from the most neutron rich stable isotope (64Ni) towards the 78Ni nucleus where the large neutron excess coincides with a double shell closure. In this framework, we have recently performed an experiment with the goal to extract the B(E2; 0+ → 2+) value for the 74Ni nucleus in an intermediate-energy Coulomb excitation experiment: preliminary results are discussed.

The study of the evolution of nuclear shells far from stability provides fundamental information about the shape and symmetry of the nuclear mean field. Nuclei with large neutron/proton ratio allow to probe the density dependence of the effective interaction. Indeed, it was recently shown that tensor and three-body forces play an important role in breaking and creating magic numbers. Of particular interest is the region of 78Ni where the large neutron excess coincides with a double shell closure. We have recently measured the B(E2; 0+ → 2+) of the 74Ni nucleus in an intermediate-energy Coulomb excitation experiment performed at the National Superconducting Cyclotron Laboratory of the Michigan State University. The 74Ni secondary beam has been produced by fragmentation of 86Kr at 140 AMeV on a thick Be target. Selected radioactive fragments impinged on a secondary 197Au target where the measurement of the emitted γ-rays allows to extract the Coulomb excitation cross section and related structure information. Preliminary B(E2) values do not point towards an enhancement of the transition matrix element and the comparison to what was already measured by Aoi and co-workers in [1] opens new scenarios in the interpretation of the shell evolution of the Z=28 isotopes.

This paper presents the concept of a modified 60E1 rail dedicated to continuous welded rail (CWR) track. The presented solution is the subject of a patent application by the authors of the publication. The paper describes problems associated with the operation of CWR track and the phenomena of so-called “rail stressing”, i.e., stresses created in the rail due to thermal shrinkage that, in extreme cases, can lead to the buckling of the rail track. Simulation calculations of longitudinal track loads to represent the occurrence of thermal force as a result of the occurrence of high air temperatures were carried out for the constructed conventional model of the railroad track as well as the track with the proposed solutions. A discussion of the simulation results is presented, indicating the possibility for the wider application of both varieties of modified rail.

Human dihydrofolate reductase (hDHFR) is an essential cellular enzyme, and inhibiting its activity is a promising strategy for cancer therapy. We have chosen the trimethoprim molecule (TMP) as a model compound in our search for a new class of hDHFR inhibitors. We incorporated an amide bond, a structural element typical of netropsin, a ligand that binds selectively in the minor groove of DNA, into the molecules of TMP analogs. In this work, we present previously obtained and evaluated eleven benzamides (JW1–JW8; MB1, MB3, MB4). Recently, these compounds were specifically projected as potential inhibitors of the enzymes acetylcholinesterase (AChE) and β-secretase (BACE1). JW8 was most active against AChE, with an inhibitory concentration of AChE IC50 = 0.056 µM, while the IC50 for donepezil was 0.046 µM. This compound was also the most active against the BACE1 enzyme. The IC50 value was 9.01 µM compared to that for quercetin, with IC50 = 4.89 µM. All the benzamides were active against hDHFR, with IC50 values ranging from 4.72 to 20.17 µM, and showed activity greater than TMP (55.26 µM). Quantitative results identified the derivatives JW2 and JW8 as the most promising. A molecular modeling study demonstrates that JW2 interacts strongly with the key residue Gly-117, while JW8 interacts strongly with Asn-64 and Arg-70. Furthermore, JW2 and JW8 demonstrate the ability to stabilize the hDHFR enzyme, despite forming fewer hydrogen bonds with the protein compared to reference ligands. It can be concluded that this class of compounds certainly holds great promise for good active leads in medicinal chemistry.

New experimental data obtained from γ-ray tagged one-neutron and one-proton knockout from Co55 are presented. A candidate for the sought-after T=1,Tz=0,Jπ=6+ state in Co54 is proposed based on a comparison to the new data on Fe54, the corresponding observables predicted by large-scale-shell-model (LSSM) calculations in the full fp-model space employing charge-dependent contributions, and isospin-symmetry arguments. Furthermore, possible isospin-symmetry breaking in the A=54, T=1 triplet is studied by calculating the experimental c coefficients of the isobaric mass multiplet equation (IMME) up to the maximum possible spin J=6 expected for the (1f7/2)-2 two-hole configuration relative to the doubly magic nucleus Ni56. The experimental quantities are compared to the theoretically predicted c coefficients from LSSM calculations using two-body matrix elements obtained from a realistic chiral effective field theory potential at next-to-next-to-next-to-leading order (N3LO).

New experimental data obtained from γ-ray tagged one-neutron and one-proton knockout from Co55 are presented. A candidate for the sought-after T=1,Tz=0,Jπ=6+ state in Co54 is proposed based on a comparison to the new data on Fe54, the corresponding observables predicted by large-scale-shell-model (LSSM) calculations in the full fp-model space employing charge-dependent contributions, and isospin-symmetry arguments. Furthermore, possible isospin-symmetry breaking in the A=54, T=1 triplet is studied by calculating the experimental c coefficients of the isobaric mass multiplet equation (IMME) up to the maximum possible spin J=6 expected for the (1f7/2)-2 two-hole configuration relative to the doubly magic nucleus Ni56. The experimental quantities are compared to the theoretically predicted c coefficients from LSSM calculations using two-body matrix elements obtained from a realistic chiral effective field theory potential at next-to-next-to-next-to-leading order (N3LO).

We present a high-resolution in-beam γ-ray spectroscopy study of excited states in the mirror nuclei Co55 and Ni55 following one-nucleon knockout from a projectile beam of Ni56. The newly determined partial cross sections and the γ-decay properties of excited states provide a test of state-of-the-art nuclear structure models and probe mirror symmetry in unique ways. The new experimental data are compared to large-scale shell-model calculations in the full pf space which include charge-dependent contributions. A mirror asymmetry for the partial cross sections leading to the two lowest 3/2- states in the A=55 mirror pair was identified as well as a significant difference in the E1 decays from the 1/21+ state to the same two 3/2- states. The mirror asymmetry in the partial cross sections cannot be reconciled with the present shell-model picture or small mixing introduced in a two-state model. The observed mirror asymmetry in the E1 decay pattern, however, points at stronger mixing between the two lowest 3/2- states in Co55 than in its mirror Ni55.

We present a high-resolution in-beam γ-ray spectroscopy study of excited states in the mirror nuclei Co55 and Ni55 following one-nucleon knockout from a projectile beam of Ni56. The newly determined partial cross sections and the γ-decay properties of excited states provide a test of state-of-the-art nuclear structure models and probe mirror symmetry in unique ways. The new experimental data are compared to large-scale shell-model calculations in the full pf space which include charge-dependent contributions. A mirror asymmetry for the partial cross sections leading to the two lowest 3/2- states in the A=55 mirror pair was identified as well as a significant difference in the E1 decays from the 1/21+ state to the same two 3/2- states. The mirror asymmetry in the partial cross sections cannot be reconciled with the present shell-model picture or small mixing introduced in a two-state model. The observed mirror asymmetry in the E1 decay pattern, however, points at stronger mixing between the two lowest 3/2- states in Co55 than in its mirror Ni55.

Cytostatic and pro-apoptotic effects of selenium steroid derivatives against HeLa cells were determined. The highest cytostatic activity was shown by derivative 4 (GI50 25.0 µM, almost complete growth inhibition after three days of culture, and over 97% of apoptotic and dead cells at 200 µM). The results of our study (cell number measurements, apoptosis profile, relative expression of apoptosis-related APAF1, BID, and mevalonate pathway-involved HMGCR, SQLE, CYP51A1, and PDHB genes, and computational chemistry data) support the hypothesis that tested selenosteroids induce the extrinsic pathway of apoptosis by affecting the cell membrane as cholesterol antimetabolites. An additional mechanism of action is possible through a direct action of derivative 4 to inhibit PDHB expression in a way similar to steroid hormones.

The spectrum of biological properties of s-triazine derivatives is broad and includes anti-microbial, anti-cancer, and anti-neurodegenerative activities, among others. The s-triazine molecule, due to the possibility of substituting three substituents, offers many opportunities to obtain hybrid compounds with a wide variety of activities. A group of 1,3,5 triazine derivatives containing a dipeptide, 2-ethylpiperazine, and a methoxy group as substituents was screened for their antimicrobial activity. An in vitro study was conducted on pathogenic bacteria (E. coli, S. aureus, B. subtilis, and M. luteus), yeasts (C. albicans), and filamentous fungi (A. fumigatus, A. flavus, F. solani, and P. citrinum) via microdilution in broth, and the results were compared with antibacterial (Streptomycin) and antifungal (Ketoconazole and Nystatin) antibiotics. Several s-triazine analogues have minimal inhibitory concentrations lower than the standard. To confirm the inhibitory potential of the most active compounds against gyrases E. coli and S. aureus, a bacterial gyrases inhibition assay, and molecular docking studies were performed. The most active s-triazine derivatives contained the -NH-Trp(Boc)-AlaOMe, -NH-Asp(OtBu)-AlaOMe, and -NH-PheOMe moieties in their structures.