Jagiellonian University

About: Jagiellonian University is a education organization based out in Krakow, Poland. It is known for research contribution in the topics: Population & Catalysis. The organization has 17438 authors who have published 44092 publications receiving 862633 citations. The organization is also known as: Academia Cracoviensis & Akademia Krakowska.

Nuclear symmetry energy and neutron skins derived from pygmy dipole resonances

Abstract: By exploiting Coulomb dissociation of high-energy radioactive beams of the neutron-rich nuclei $^{129\ensuremath{-}132}\mathrm{Sn}$ and $^{133,134}\mathrm{Sb}$, their dipole-strength distributions have been measured. A sizable fraction of ``pygmy'' dipole strength, energetically located below the giant dipole resonance, is observed in all of these nuclei. A comparison with available pygmy resonance data in stable nuclei ($^{208}\mathrm{Pb}$ and $N=82$ isotones) indicates a trend of strength increasing with the proton-to-neutron asymmetry. On theoretical grounds, employing the RQRPA approach, a one-to-one correlation is found between the pygmy strength and parameters describing the density dependence of the nuclear symmetry energy, and in turn with the thicknesses of the neutron skins. On this basis, by using the experimental pygmy strength, parameters of the nuclear symmetry energy (${a}_{4}=32.0\ifmmode\pm\else\textpm\fi{}1.8$ MeV and ${p}_{o}=2.3\ifmmode\pm\else\textpm\fi{}0.8$ MeV/fm${}^{3}$) are deduced as well as neutron-skin thicknesses ${R}_{n}\ensuremath{-}{R}_{p}$ of $0.24\ifmmode\pm\else\textpm\fi{}0.04$ fm for $^{132}\mathrm{Sn}$ and of $0.18\ifmmode\pm\else\textpm\fi{}0.035$ fm for $^{208}\mathrm{Pb}$, both doubly magic nuclei. Astrophysical implications with regard to neutron stars are briefly addressed.

Uncovering archaeological landscapes at Angkor using lidar

Abstract: Previous archaeological mapping work on the successive medieval capitals of the Khmer Empire located at Angkor, in northwest Cambodia (∼9th to 15th centuries in the Common Era, C.E.), has identified it as the largest settlement complex of the preindustrial world, and yet crucial areas have remained unmapped, in particular the ceremonial centers and their surroundings, where dense forest obscures the traces of the civilization that typically remain in evidence in surface topography. Here we describe the use of airborne laser scanning (lidar) technology to create high-precision digital elevation models of the ground surface beneath the vegetation cover. We identify an entire, previously undocumented, formally planned urban landscape into which the major temples such as Angkor Wat were integrated. Beyond these newly identified urban landscapes, the lidar data reveal anthropogenic changes to the landscape on a vast scale and lend further weight to an emerging consensus that infrastructural complexity, unsustainable modes of subsistence, and climate variation were crucial factors in the decline of the classical Khmer civilization.

Heterochromatin protein 1 is recruited to various types of DNA damage

Abstract: Heterochromatin protein 1 (HP1) family members are chromatin-associated proteins involved in transcription, replication, and chromatin organization. We show that HP1 isoforms HP1-α, HP1-β, and HP1-γ are recruited to ultraviolet (UV)-induced DNA damage and double-strand breaks (DSBs) in human cells. This response to DNA damage requires the chromo shadow domain of HP1 and is independent of H3K9 trimethylation and proteins that detect UV damage and DSBs. Loss of HP1 results in high sensitivity to UV light and ionizing radiation in the nematode Caenorhabditis elegans, indicating that HP1 proteins are essential components of DNA damage response (DDR) systems. Analysis of single and double HP1 mutants in nematodes suggests that HP1 homologues have both unique and overlapping functions in the DDR. Our results show that HP1 proteins are important for DNA repair and may function to reorganize chromatin in response to damage.

Adjunctive manual thrombectomy improves myocardial perfusion and mortality in patients undergoing primary percutaneous coronary intervention for ST-elevation myocardial infarction: a meta-analysis of randomized trials

Abstract: Aims The benefits of adjunctive mechanical devices to prevent distal embolization in patients with acute myocardial infarction (AMI) are still a matter of debate. Growing interests are on manual thrombectomy devices as compared with other mechanical devices. In fact, they are inexpensive and user-friendly devices, and thus represent an attractive strategy. The aim of the current study was to perform an updated meta-analysis of randomized trials conducted with adjunctive manual thrombectomy devices to prevent distal embolization in AMI. Methods and results The literature was scanned by formal searches of electronic databases [MEDLINE, CENTRAL, EMBASE, and The Cochrane Central Register of Controlled trials (http://www.mrw.interscience.wiley.com/cochrane/Cochrane\_clcentral\_articles_ fs.html)] from January 1990 to May 2008, the scientific session abstracts (from January 1990 to May 2008) and oral presentation and/or expert slide presentations (from January 2002 to May 2008) [on transcatheter coronary therapeutics (TCT), AHA (American Heart Association), ESC (European Society of Cardiology), ACC (American College of Cardiology) and EuroPCR websites]. We examined all randomized trials on adjunctive mechanical devices to prevent distal embolization in AMI. The following keywords were used: randomized trial, myocardial infarction, reperfusion, primary angioplasty, rescue angioplasty, thrombectomy, thrombus aspiration, manual thrombectomy, Diver catheter, Pronto catheter, Export catheter, thrombus vacuum aspiration catheter. Information on study design, type of device, inclusion and exclusion criteria, number of patients, and clinical outcome was extracted by two investigators. Disagreements were resolved by consensus. A total of nine trials with 2417 patients were included [1209 patients (50.0%) in the manual thrombectomy device group and 1208 (50%) in the control group]. Adjunctive manual thrombectomy was associated with significantly improved postprocedural TIMI (thrombolysis in myocardial infarction) 3 flow (87.1 vs. 81.2%, P < 0.0001), and postprocedural MBG 3 (myocardial blush grade 3) (52.1 vs. 31.7%, P < 0.0001), less distal embolization (7.9 vs. 19.5%, P < 0.0001), and significant benefits in terms of 30-day mortality (1.7 vs. 3.1%, P = 0.04). Conclusion This meta-analysis demonstrates that, among patients with AMI treated with percutaneous coronary intervention, the use of adjunctive manual thrombectomy devices is associated with better epicardial and myocardial perfusion, less distal embolization and significant reduction in 30-day mortality. Thus, adjunctive manual thrombectomy devices, if not anatomically contraindicated, should be routinely used among STEMI (ST-segment elevation myocardial infarction) patients undergoing primary angioplasty.