798 research outputs found
The role of mentorship in protege performance
The role of mentorship on protege performance is a matter of importance to
academic, business, and governmental organizations. While the benefits of
mentorship for proteges, mentors and their organizations are apparent, the
extent to which proteges mimic their mentors' career choices and acquire their
mentorship skills is unclear. Here, we investigate one aspect of mentor
emulation by studying mentorship fecundity---the number of proteges a mentor
trains---with data from the Mathematics Genealogy Project, which tracks the
mentorship record of thousands of mathematicians over several centuries. We
demonstrate that fecundity among academic mathematicians is correlated with
other measures of academic success. We also find that the average fecundity of
mentors remains stable over 60 years of recorded mentorship. We further uncover
three significant correlations in mentorship fecundity. First, mentors with
small mentorship fecundity train proteges that go on to have a 37% larger than
expected mentorship fecundity. Second, in the first third of their career,
mentors with large fecundity train proteges that go on to have a 29% larger
than expected fecundity. Finally, in the last third of their career, mentors
with large fecundity train proteges that go on to have a 31% smaller than
expected fecundity.Comment: 23 pages double-spaced, 4 figure
Apurinic/Apyrimidinic Endonuclease/Redox Factor-1 (APE1/Ref-1) redox function negatively regulates NRF2
Apurinic/apyrimidinic endonuclease/redox factor-1 (APE1/Ref-1) (henceforth referred to as Ref-1) is a multifunctional protein that in addition to its base excision DNA repair activity exerts redox control of multiple transcription factors, including nuclear factor κ-light chain enhancer of activated B cells (NF-κB), STAT3, activator protein-1 (AP-1), hypoxia-inducible factor-1 (HIF-1), and tumor protein 53 (p53). In recent years, Ref-1 has emerged as a promising therapeutic target in cancer, particularly in pancreatic ductal carcinoma. Although a significant amount of research has centered on Ref-1, no wide-ranging approach had been performed on the effects of Ref-1 inhibition and transcription factor activity perturbation. Starting with a broader approach, we identified a previously unsuspected effect on the nuclear factor erythroid-related factor 2 (NRF2), a critical regulator of cellular defenses against oxidative stress. Based on genetic and small molecule inhibitor-based methodologies, we demonstrated that repression of Ref-1 potently activates NRF2 and its downstream targets in a dose-dependent fashion, and that the redox, rather than the DNA repair function of Ref-1 is critical for this effect. Intriguingly, our results also indicate that this pathway does not involve reactive oxygen species. The link between Ref-1 and NRF2 appears to be present in all cells tested in vitro, noncancerous and cancerous, including patient-derived tumor samples. In particular, we focused on understanding the implications of the novel interaction between these two pathways in primary pancreatic ductal adenocarcinoma tumor cells and provide the first evidence that this mechanism has implications for overcoming the resistance against experimental drugs targeting Ref-1 activity, with clear translational implications
Use of domesticated pigs by Mesolithic hunter-gatherers in northwestern Europe
Acknowledgements We thank the Archaeological State Museum Schleswig-Holstein, the Archaeological State Offices of Brandenburg, Lower Saxony and Saxony and the following individuals who provided sample material: Betty Arndt, Jo¨rg Ewersen, Frederick Feulner, Susanne Hanik, Ru¨diger Krause, Jochen Reinhard, Uwe Reuter, Karl-Heinz Ro¨hrig, Maguerita Scha¨fer, Jo¨rg Schibler, Reinhold Schoon, Regina Smolnik, Thomas Terberger and Ingrid Ulbricht. We are grateful to Ulrich Schmo¨lcke, Michael Forster, Peter Forster and Aikaterini Glykou for their support and comments on the manuscript. We also thank many institutions and individuals that provided sample material and access to collections, especially the curators of the Museum fu¨r Naturkunde, Berlin; Muse´um National d0 Histoire Naturelle, Paris; Smithsonian Institution, National Museum of Natural History, Washington D.C.; Zoologische Staatssammlung, Mu¨nchen; Museum fu¨r Haustierkunde, Halle; the American Museum of Natural History, New-York. This work was funded by the Graduate School ‘Human Development in Landscapes’ at Kiel University (CAU) and supported by NERC project Grant NE/F003382/1. Radiocarbon dating was carried out at the Leibniz Laboratory, CAU. This work is licensed under a Creative Commons AttributionNonCommercial-NoDerivs 3.0 Unported License.Peer reviewedPublisher PD
A Joint Inversion of Ground Deformation and Focal Mechanisms Data for Magmatic Source Modelling
The paucity of geodetic data acquired on active volcanoes can make the understanding of modelling magmatic systems quite difficult. In this study, we propose a novel approach, which allows improving the parameter estimation of analytical models of magmatic sources (e.g., shape, depth, dimensions, volume change, etc.) by means of a joint inversion of surface ground deformation data and P-axes of focal plane solutions. The methodology is first verified against a synthetic dataset of surface deformation and strain within the medium, and then applied to real data from an unrest episode occurred before the May 13 2008 eruption at Mt. Etna (Italy). The main results clearly indicate the joint inversion improves the accuracy of the estimated source parameters by about 70 %. The statistical tests indicate that the source depth is the parameter with the highest increment of accuracy. In addition, a sensitivity analysis confirms that displacements data are more useful to constrain the pressure and the horizontal location of the source than its depth, while the P-axes better constrain the depth estimation
Violent paroxysmal activity drives self-feeding magma replenishment at Mt. Etna
A new sequence of eruptions occurred at Mt. Etna volcano during the first half of 2017, after almost 8 months of quiescence. These episodes had low-to-mild intensity and markedly differ from the violent paroxysms occurred at the Voragine Crater (VOR) during December 2015 and May 2016. Despite the general weak explosive nature of the eruptions, the activity during 2017 revealed unusually complex dynamics of magma ascent and interaction. Detection and investigation of such dynamics required a multidisciplinary approach in which bulk rock compositions, crystal chemical zoning, diffusion chronometry and ground deformation data have been combined. Bulk rock major and trace elements suggest that the 2017 magmas followed a differentiation path similar to that experienced by magmas erupted at Mt. Etna during the 2015–16 eruptions at VOR. Olivine core compositions and zoning patterns indicate the presence of multiple magmatic environments at depth that strictly interacted each other through some episodes of intrusion and mixing before and during the 2017 eruptive events. Timescales retrieved from diffusion chronometry on olivine normal and reverse zoning correlate well with the ground deformation stages detected through geodetic data and associated models, thus allowing to track the evolution through time of the 2017 volcanic activity. Combination of all petrological and geodetic observations supports the idea that dynamics of magma transfer driving the eruptive episodes of 2017 have been a direct consequence of the violent eruptions occurred at VOR on May 2016, which boosted the ascent of new magma from depth and improved the efficiency of the plumbing system to transfer it upward to the surface. We propose a mechanism of self-feeding replenishment of the volcano plumbing system during 2017, where magma recharge from depth is triggered by sudden unloading of the magma column consequential to the violent paroxysmal activity occurred on May 2016 at VOR
A high throughput genotyping approach reveals distinctive autosomal genetic signatures for European and Near Eastern wild boar
The lack of a Near Eastern genetic signature in modern European porcine breeds indicates that, although domestic pigs from the Fertile Crescent entered Europe during the Neolithic, they were completely replaced by their European counterparts in a short window of time. Whilst the absence of such genetic signature has been convincingly demonstrated at the mitochondrial level, variation at the autosomal genomes of European and Near Eastern Sus scrofa has not been compared yet. Herewith, we have explored the genetic relationships among 43 wild boar from Europe (N = 21), Near East (N = 19) and Korea (N = 3), and 40 Iberian (N = 16), Canarian (N = 4) and Mangalitza (N = 20) pigs by using a high throughput SNP genotyping platform. After data filtering, 37,167 autosomal SNPs were used to perform population genetics analyses. A multidimensional scaling plot based on genome-wide identity-by-state pairwise distances inferred with PLINK showed that Near Eastern and European wild boar populations are genetically differentiated. Maximum likelihood trees built with TreeMix supported this conclusion i.e. an early population split between Near Eastern and European Sus scrofa was observed. Moreover, analysis of the data with Structure evidenced that the sampled Iberian, Canarian and Mangalitza pigs did not carry any autosomal signature compatible with a Near Eastern ancestry, a finding that agrees well with previous mitochondrial studies
Percutaneous mitral valve edge-to-edge Repair: In-hospital results and 1-year follow-up of 628 patients of the 2011-2012 pilot European Sentinel Registry
The use of transcatheter mitral valve repair (TMVR) has gained widespread acceptance in Europe, but data on immediate success, safety, and long-term echocardiographic follow-up in real-world patients are still limited
Perusopetukseen valmistavan opetuksen opettajien kokemuksia saamastaan sosiaalisesta tuesta
Tiivistelmä. Tämän pro gradu -tutkielman tavoitteena on selvittää, millaisia kokemuksia perusopetukseen valmistavan opetuksen opettajilla on sosiaalisesta tuesta. Perusopetukseen valmistava opetus on perusopetuksen ulkopuolista opetusta, joka on suunnattu maahanmuuttajataustaisille lapsille ja nuorille, joiden suomen kielen taito ei ole vielä riittävä perusopetuksessa opiskeluun. Perusopetukseen valmistavan opetuksen tavoitteena on muun muassa kotoutumisen edistäminen ja kielitaidon kehittäminen. Opetuksen suunnittelussa huomioidaan oppilaiden ikäkausi sekä taitotaso. Kielitaidon kehittyessä oppilaita integroidaan perusopetuksen ryhmiin.
Sosiaalisen tuen kokemuksia tarkastellaan kolmesta eri näkökulmasta, jotka ovat omalta koululta, toisilta valmistavan opetuksen opettajilta sekä muilta tahoilta saatu sosiaalinen tuki. Tässä tutkimuksessa sosiaalinen tuki on jaettu kolmeen osa-alueeseen, jotka ovat välineellinen tuki, emotionaalinen tuki ja tiedollinen tuki. Välineellinen tuki on konkreettista apua, kuten työvälineiden tai materiaalin jakamista. Emotionaaliseen tukeen liitetään esimerkiksi empatiakyky, kunnioittaminen ja arvostus toisia kohtaan. Tiedollinen tuki on neuvojen ja ehdotusten antamista.
Sosiaalinen tuki on riippuvainen yksilön sosiaalisista suhteista sekä ympäristöstä ja se voi olla joko vastaanotettua tai annettua. Sosiaalisella tuella nähdään olevan positiivisia vaikutuksia yksilön terveyteen ja lisäksi sosiaalinen tuki auttaa yksilöä selviytymään haastavista tilanteista vähentäen stressin oireita. Vähäinen sosiaalinen tuki voi heikentää yksilön itsetuntoa ja johtaa psykologisiin ongelmiin. Työpaikalla sosiaalisella tuella on merkittävä vaikutus työhyvinvointiin ja työkykyyn. Lisäksi se edistää työhön sitoutumista ja oman ammattitaidon kehittymistä. Sosiaalisen tuen puute työpaikalla voi näkyä motivaation puutteena ja ahdistuksena.
Tämä tutkimus on toteutettu fenomenologisella tutkimusotteella, koska tutkimuksen tarkoituksena on selvittää perusopetukseen valmistavan opetuksen opettajien kokemuksia. Tutkimusaineisto on kerätty teemahaastattelulla ja tutkimukseen osallistui kuusi perusopetukseen valmistavan opetuksen opettajaa. Aineisto on analysoitu teoriaohjaavan sisällönanalyysimenetelmän mukaisesti.
Tutkimustulosten perusteella perusopetukseen valmistavan opetuksen opettajat kokevat saavansa sosiaalista tukea oman koulun henkilökunnalta, toisilta valmistavan opetuksen opettajilta sekä muilta tahoilta. Toisaalta tutkimustuloksissa esiintyi myös puutteellisia kokemuksia sosiaalisesta tuesta. Tutkimustuloksissa emotionaalisen ja tiedollisen tuen kokemuksia oli käsitelty yhtä laajasti ja välineellisen tuen kokemuksia opettajat olivat maininneet selkeästi vähiten
A standardized approach to empirically define reliable assignment thresholds and appropriate management categories in deeply introgressed populations
Anthropogenic hybridization is recognized as a major threat to the long-term survival of natural populations. While identifying F1 hybrids might be simple, the detection of older admixed individuals is far from trivial and it is still debated whether they should be targets of management. Examples of anthropogenic hybridization have been described between wolves and domestic dogs, with numerous cases detected in the Italian wolf population. After selecting appropriate wild and domestic reference populations, we used empirical and simulated 39-autosomal microsatellite genotypes, Bayesian assignment and performance analyses to develop a workflow to detect different levels of wolf x dog admixture. Membership proportions to the wild cluster (qiw) and performance indexes identified two q-thresholds which allowed to efficiently classify the analysed genotypes into three assignment classes: pure (with no or negligible domestic ancestry), older admixed (with a marginal domestic ancestry) and recent admixed (with a clearly detectable domestic ancestry) animals. Based on their potential to spread domestic variants, such classes were used to define three corresponding management categories: operational pure, introgressed and operational hybrid individuals. Our multiple-criteria approach can help wildlife managers and decision makers in more efficiently targeting the available resources for the long-term conservation of species threatened by anthropogenic hybridization
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