138 research outputs found

    De Haas-van Alphen oscillations in the charge-density wave compound lanthanum tritelluride (LaTe_3)

    Full text link
    De Haas-van Alphen oscillations were measured in lanthanum tritelluride (LaTe_3) to probe the partially gapped Fermi surface resulting from charge density wave (CDW) formation. Three distinct frequencies were observed, one of which can be correlated with a FS sheet that is unaltered by CDW formation. The other two frequencies arise from FS sheets that have been reconstructed in the CDW state.Comment: 8 page

    Axial tubule junctions control rapid calcium signaling in atria.

    Get PDF
    The canonical atrial myocyte (AM) is characterized by sparse transverse tubule (TT) invaginations and slow intracellular Ca2+ propagation but exhibits rapid contractile activation that is susceptible to loss of function during hypertrophic remodeling. Here, we have identified a membrane structure and Ca2+-signaling complex that may enhance the speed of atrial contraction independently of phospholamban regulation. This axial couplon was observed in human and mouse atria and is composed of voluminous axial tubules (ATs) with extensive junctions to the sarcoplasmic reticulum (SR) that include ryanodine receptor 2 (RyR2) clusters. In mouse AM, AT structures triggered Ca2+ release from the SR approximately 2 times faster at the AM center than at the surface. Rapid Ca2+ release correlated with colocalization of highly phosphorylated RyR2 clusters at AT-SR junctions and earlier, more rapid shortening of central sarcomeres. In contrast, mice expressing phosphorylation-incompetent RyR2 displayed depressed AM sarcomere shortening and reduced in vivo atrial contractile function. Moreover, left atrial hypertrophy led to AT proliferation, with a marked increase in the highly phosphorylated RyR2-pS2808 cluster fraction, thereby maintaining cytosolic Ca2+ signaling despite decreases in RyR2 cluster density and RyR2 protein expression. AT couplon "super-hubs" thus underlie faster excitation-contraction coupling in health as well as hypertrophic compensatory adaptation and represent a structural and metabolic mechanism that may contribute to contractile dysfunction and arrhythmias

    Human Resource Flexibility as a Mediating Variable Between High Performance Work Systems and Performance

    Get PDF
    Much of the human resource management literature has demonstrated the impact of high performance work systems (HPWS) on organizational performance. A new generation of studies is emerging in this literature that recommends the inclusion of mediating variables between HPWS and organizational performance. The increasing rate of dynamism in competitive environments suggests that measures of employee adaptability should be included as a mechanism that may explain the relevance of HPWS to firm competitiveness. On a sample of 226 Spanish firms, the study’s results confirm that HPWS influences performance through its impact on the firm’s human resource (HR) flexibility

    Velocity-space sensitivity of the time-of-flight neutron spectrometer at JET

    Get PDF
    The velocity-space sensitivities of fast-ion diagnostics are often described by so-called weight functions. Recently, we formulated weight functions showing the velocity-space sensitivity of the often dominant beam-target part of neutron energy spectra. These weight functions for neutron emission spectrometry (NES) are independent of the particular NES diagnostic. Here we apply these NES weight functions to the time-of-flight spectrometer TOFOR at JET. By taking the instrumental response function of TOFOR into account, we calculate time-of-flight NES weight functions that enable us to directly determine the velocity-space sensitivity of a given part of a measured time-of-flight spectrum from TOFOR

    The Reproductive Revolution

    Get PDF
    Este texto fue publicado en 2009 por The Sociological Review. Rogamos que, a efectos de divulgación, docencia y cita bibliográfica se acuda a la publicación impresa (u online de la propia revista) y la cita sea esta: MacInnes, J., Pérez Díaz, J. (2009), "The reproductive revolution" The Sociological Review 57 (2): 262-284. Su versión html puede encontrarse en esta dirección:http://www3.interscience.wiley.com/cgi-bin/fulltext/122368561/HTMLSTART Quienes estén interesados en ampliar la información sobre nuestra Teoría de la Revolución Reproductiva pueden visitar la página web siguiente: http://www.ieg.csic.es/jperez/pags/RRweb/RRweb.htm También encontrarán en este mismo repositorio otra publicación con unaexposición en castellano de las mismas ideas y publicada en la REIS bajo el título “La tercera revolución de la modernidad: la reproductiva”.We suggest that a third revolution alongside the better known economic and political ones has been vital to the rise of modernity: the reproductive revolution, comprising a historically unrepeatable shift in the efficiency of human reproduction which for the first time brought demographic security.As well as highlighting the contribution of demographic change to the rise of modernity and addressing the limitations of orthodox theories of the demographic transition, the concept of the reproductive revolution offers a better way to integrate sociology and demography. The former has tended to pay insufficient heed to sexual reproduction, individual mortality and the generational replacement of population, while the latter has undervalued its own distinctive theoretical contribution, portraying demographic change as the effect of causes lying elsewhere. We outline a theory of the reproductive revolution, review some relevant supporting empirical evidence and briefly discuss its implications both for demographic transition theory itself, and for a range of key social changes that we suggest it made possible: the decline of patriarchy and feminisation of the public sphere, the deregulation and privatisation of sexuality, family change, the rise of identity, ‘low’ fertility and ‘population ageing’.Peer reviewe

    A Comprehensive Pan-Cancer Molecular Study of Gynecologic and Breast Cancers

    Get PDF
    We analyzed molecular data on 2,579 tumors from The Cancer Genome Atlas (TCGA) of four gynecological types plus breast. Our aims were to identify shared and unique molecular features, clinically significant subtypes, and potential therapeutic targets. We found 61 somatic copy-number alterations (SCNAs) and 46 significantly mutated genes (SMGs). Eleven SCNAs and 11 SMGs had not been identified in previous TCGA studies of the individual tumor types. We found functionally significant estrogen receptor-regulated long non-coding RNAs (lncRNAs) and gene/lncRNA interaction networks. Pathway analysis identified subtypes with high leukocyte infiltration, raising potential implications for immunotherapy. Using 16 key molecular features, we identified five prognostic subtypes and developed a decision tree that classified patients into the subtypes based on just six features that are assessable in clinical laboratories. By performing molecular analyses of 2,579 TCGA gynecological (OV, UCEC, CESC, and UCS) and breast tumors, Berger et al. identify five prognostic subtypes using 16 key molecular features and propose a decision tree based on six clinically assessable features that classifies patients into the subtypes

    The trace element and humoral immune response of lambs administered a zinc, cobalt and selenium soluble glass bolus

    No full text
    Zinc, cobalt and selenium are essential trace elements for ruminants and all have roles in immune function. The delivery of these elements to grazing livestock can be problematical. The aim of this trial is to determine the effect of the administration of an intraruminal soluble glass bolus to supply zinc, cobalt and selenium to growing lambs at pasture and to determine the effect on humoral immune response via the administration of a novel keyhole limpet haemacyanin (KLH) antigen. On days 0, 17 lambs each had a zinc (15.1% w/w), cobalt (0.52% w/w) and selenium (0.15% w/w) soluble glass bolus (∼33 g) administered (bolused), whilst the 17 lambs received no bolus (control). All of the lambs were grazed together throughout the trial. Trace element status (selenium—erythrocyte glutathione peroxidise activity; cobalt—serum vitamin B12 concentration; zinc—plasma zinc concentration) and live weights were assessed on days 0, 20, 42 and 63, with immunisation with KLH on day 34 and assessment of IgG response by direct ELISA on days 20, 42, 49, 63. Lambs were slaughtered when commercially fit on either day 86 or 121 and livers analysed for copper and zinc concentrations and boluses recovered from the bolus group to assess dissolution rates. The bolused lambs had significantly increased serum vitamin B12 concentrations (p<0.001) and erythrocyte glutathione peroxidase activities (p<0.001) on all post-bolusing samplings. The bolused lambs had higher plasma zinc concentrations on day 42 (p<0.05) and day 63 (p<0.01). The humoral immune response was enhanced with the bolused lambs having significantly greater anti-KLH IgG levels on day 42 (p<0.05) and day 63 (p<0.01), although the two groups had a similar maximal value at day 49. There was no significant effect of the bolus on live-weight or liver zinc concentrations. The average bolus dissolution rate of the recovered boluses was 326 mg glass/d (s.d.±30 mg/d) giving a mean daily release of 49.3 mg zinc, 1.7 mg cobalt and 0.5 mg selenium. The pasture mineral status was not assessed, but the bolus alone was able to fulfil recommended intake requirements for the elements. In conclusion, administration of a zinc, cobalt and selenium soluble glass bolus resulted in an increased antibody response and fulfilled the daily requirements for cobalt, selenium and zinc with an elevated status of these elements compared to unsupplemented controls grazing the same pasture
    corecore