54 research outputs found

    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

    56W frequency doubled source at 530 nm pumped by a single-mode single-polarization picosecond Yb<sup>3+</sup>-doped fiber MOPA

    No full text
    We report a frequency doubled green source at 530nm pumped based on an all-fiber, picosecond, single polarization Yb3+-doped fiber MOPA delivering 20ps pulses at user selectable repetition rates of up to 910MHz and an average output power in excess of 100W at 1.06µm. The output of the MOPA was frequency doubled using a LBO crystal. Up to 56 W of green light was generated at a corresponding repetition rate of 227 MHz at an overall conversion efficiency of 56%. The diode-to-green optical power conversion efficiency was 37%

    Picosecond fiber MOPA pumped supercontinuum source with 39W output power

    No full text
    We report picosecond fiber MOPA pumped supercontinuum source with 39W output, spanning at least 0.4-1.75 µm with high and relatively uniform spectral power density of ~31.7mW/nm corresponding to peak power density of ~12.5W/nm in 20ps pulse

    Over 55W of frequency doubled light at 530nm pumped by an all-fiber diffraction limited picosecond fibre MOPA

    No full text
    We report the realisation of a high power, picosecond pulse source at 530 nm pumped by an all-fiber, single mode, single polarisation, Yb-doped MOPA. The pump MOPA comprised of a gain switched seed source generating 20 ps pulse source at a repetition frequency of 910 MHz followed by three amplification stages. Output power in excess of 100 W was obtained at 85% slope efficiency with respect to launched pump power at 975 nm. A 15mm long LBO crystal was used to frequency double the single mode, single polarisation output of the fiber MOPA. To satisfy the phase matching condition, the internal temperature of the LBO crystal was maintained at 1550C. Frequency doubled power in excess of 55 W was obtained at 56% optical-to-optical conversion efficiency. Output power at 530 nm started to roll-off after 50 W due to self-phase modulation (SPM) assisted spectral broadening of the fundamental light within the final stage amplifier. Measured spectral bandwidth of the frequency doubled signal remained at ~0.4 nm with the increase in fundamental power even though that of the fundamental increased steadily with output power and reached to a value of 0.9 nm at 100 W output power

    Temporally and spatially shaped fully-fiberized ytterbium-doped pulsed MOPA

    No full text
    We report a fully-fiberized, pulsed ytterbium-doped master oscillator power amplifier (MOPA) for materials processing applications providing both a temporal pulse and spatial beam shaping capability operating at a maximum average output power of 100 W. Adaptive temporal pulse shaping using an in-line electro-optic modulator was incorporated to reduce the impact of dynamic gain saturation and optical Kerr/Raman nonlinearities. The MOPA is capable of generating 2.5 mJ flattopped optical pulses with 20 kW peak power as well as other user-defined, shaped pulses. Spatial beam shaping is obtained using a pair of axicon (conical) lenses at the end of the beam delivery optic allowing ring shaped output beams to be generated from the otherwise collimated Gaussian output
    corecore