Microcontroller based double beam modulation system for atomic scattering experiments

Double beam modulation is widely used in atomic collision experiments in the case where the noise arising froth each of the beams exceeds the measured signal. A method for minimizing the statistical uncertainty in a measured signal in a given time period is discussed, and a flexible modulation and counting system based on a low cost PIC microcontroller is described. This device is capable of modifying the acquisition parameters in real time during the course of an experimental run. It is shown that typical savings in data acquisition time of approximately 30% can be achieved using this optimized modulation scheme.

Ecoturismo en comunidades rurales: análisis de los impactos negativos para la población local. Un estudio de caso

En los últimos años han aparecido nuevas formas de turismo más sostenibles, donde existen elementos relacionados con el descanso, el disfrute y la protección del medio ambiente o el conocimiento de la cultura local, a través de políticas que favorecen la sostenibilidad del destino. En este sentido, el ecoturismo se configura como una tipología turística que se desarrolla en contacto con la naturaleza. Este turismo ayuda a mejorar el desarrollo socioeconómico de las comunidades locales, a la vez, que fomenta la conservación de los recursos naturales y el respeto hacia el medio ambiente. Aunque, esta tipología de turismo también genera importantes impactos negativos. El objetivo principal de esta investigación es analizar los impactos socioeconómicos, culturales y medioambientales percibidos por el ecoturismo por parte de los residentes de comunidades rurales de República Dominicana. La técnica de recolección de datos utilizada ha consistido en un cuestionario. Entre las principales conclusiones, cabe destacar que actualmente no se perciben impactos negativos, pero si hay una serie de elementos que hay que ir considerando, con la finalidad de que no se conviertan en un impacto a corto plazo para la comunidad rural.

Above Threshold Dissociation of Vibrationally Cold HD+ Molecules

The experimental study of molecular dissociation of H2+ by intense laser pulses is complicated by the fact that the ions are initially produced in a wide range of vibrational states, each of which responds differently to the laser field. An electrostatic storage device has been used to radiatively cool HD+ ions enabling the observation of above threshold dissociation from the ground vibrational state by 40 fs laser pulses at 800 nm. At the highest intensities used, dissociation through the absorption of at least four photons is found to be the dominant process.

Measurement of charge exchange and X-ray emission cross sections for solar wind-comet interactions

X-ray emission from a comet was observed for the first time in 1996. One of the mechanisms believed to be contributing to this surprisingly strong emission is the interaction of highly charged solar wind ions with cometary gases. Reported herein are total absolute charge-exchange and normalized line-emission (X-ray) cross sections for collisions of high-charge state (+3 to +10) C, N, O, and Ne ions with the cometary species H2O and CO2. It is found that in several cases the double charge-exchange cross sections can be large, and in the case of C3+ they are equal to those for single charge exchange. Present results are compared to cross section values used in recent comet models. The importance of applying accurate cross sections, including double charge exchange, to obtain absolute line-emission intensities is emphasized.

Variation in offspring size towards the high elevational range edge of a montane annual

Understanding the ecological determinants of species’ distribution is a fundamental goal of ecology, and is increasingly important with changing limits to species’ range. Species often reach distributional limits on gradients of resource availability, but the extent to which offspring provisioning varies towards range limits is poorly understood. Selection is generally expected to favour higher provisioning of individual offspring in environments with short growing seasons and limited moisture, nutrients, or hosts for parasitism. However, individual provisioning may decline if parent size is limited by resources. This thesis focuses on three major questions: 1) does seed size vary over an elevational gradient? 2) does this variation respond adaptively towards the range limit? and 3) is potential elevational variation environmentally or genetically controlled? I tested variation in seed investment towards the upper elevational limit of the hemiparasitic annual herb Rhinanthus minor, sampled across an elevational range of 1,000m in the Rocky Mountains of Alberta, Canada. I also used a reciprocal transplant experiment to address the heritability of seed mass. Seed mass increased marginally towards higher elevations, while seed number and plant size declined. There was a strong elevational increase in seed mass scaled by overall plant size. Therefore, investment in individual seeds was higher towards the upper range edge, indicating potential adaptation of the reproductive strategy to allow for establishment in marginal environments. Genetic, environmental, and genotype-by-environment interactions were observed in transplanted populations, but the relative proportions of these effects on seed size were unclear.

The Complete Works of John Milton: Volume III: The Shorter Poems (816pp.)

Volume III of the new eleven-volume edition of Milton's Complete Works provides a definitive scholarly edition of all of Milton's shorter poems in English, Latin, Italian, and Greek, as well as his Mask, taken from both published and manuscript sources. It includes his 1645 Poems complete with all prefatory materials, thus illuminating the ways in which author, publisher, and print shop shaped this volume. It then presents all the new poems added in the 1673 edition (with the new Table of Contents), as well as the poems omitted from both editions. A careful collation of textual variants among these sources as well as the 1637 anonymous publication of Milton's Mask is provided. The Bridgewater manuscript of Milton's Mask (probably close to the acting version) and his working copy from the Trinity Manuscript, with its many alterations and additions, are transcribed in their entirety, so that the various versions may be compared and studied. 

A special feature of this edition is a new translation of Milton's many Latin and Greek poems that is both accurate and attentive to their literary qualities. This is augmented by a detailed and comprehensive commentary that highlights classical, vernacular, and neo-Latin parallels. A poetic translation of Milton's six Italian sonnets and Canzone is also supplied. In addition, the Appendices contain all the versions of Milton's shorter poems in all the contemporary manuscript and printed sources, so they may be examined in relation to their specific contexts. The transcription of all the versions of Milton's poems in the Trinity Manuscript allows in several cases, notably 'Lycidas' and 'At a Solemn Music,' for examination of the evolution of these poems as Milton weighed choiced of diction and sound qualities, enabling further understanding of his poetic practices. 

Barbara Lewalski is responsible for text, textual apparatus, and commentary pertaining to the vernacular poems in all sections of this edition including the appendices, and manuscript transcriptions (with the exception of A Maske), as well as the Occasions, Vernacular Poems,and Textual Introductions. Estelle Haan is responsible for text, textual apparatus, and commentary for the Poemata in all sections of this edition,and for the Poemata Introduction. She has also provided all translations from Latin, Italian, and Greek in the Testimonia, Poemata, and associated commentary, and transcriptions of the BL Damon, the Bodleian AdJoannem Rousium, and A Maske from the Trinity and Bridgewater manuscripts. Andrew McNeillie has provided poetic translations for Milton’s Italian sonnets, and Jason Rosenblatt has provided some Hebrew text and commentary pertaining to Milton’s Psalm translations.John Cunningham has transcribed Henry Lawes’ music for Milton’s masque, with commentary (Appendix E). Biblical references are taken from the King James (Authorized) Version.

Alien gosd in the new epics: Noah remythologised through the ancient astronaut hypothesis in Abel's Montagut's "La gesta d'Utnoa"

Modern scientific world-view has undermined traditional myths, the functional survival of which seems to depend today in the West on a positivist justification. This would place them in the field of real History, through their study and revitalization by pseudoscientific disciplines such as the Atlantis and the ancient astronaut hypotheses. These have inspired new epic poems in (regular) verse that combine classic and/or biblical myths with a (pseudo)scientific modern world-view. For example, the critical rewriting of Noah’s myth by using the ancient astronaut hypothesis as a fictional device to produce a contemporary kind of plausibility allowed Abel Montagut to renew epic poetry, updating it also by adopting science fiction chronotopes in order to structure his fictional construction and to generate a high ethical sense for our time. Thus, his Poemo de Utnoa (1993) / La gesta d’Utnoa (1996), which has become a major classic of the literature in Esperanto thanks to its original version in this language, is a landmark of both science fiction and neo-biblical epics. This poem is written from a secular and purely literary perspective.

‘Close as a kiss’: Gyn/Affection in Margaret Atwood’s The Penelopiad

Margaret Atwood’s novella The Penelopiad (2005) seemingly celebrates Penelope’s agency in opposition to Homer’s myth in The Odyssey. However, the twelve murdered maids steal the book to suggest the possibility of what Janice Raymond calls gyn/affection, a female bonding based on the logic of emotion that, in Atwood’s revision, verges on Kristevan abjection, the sinister and the fantastic, and serves a cathartic effect not only in the maids but also in the reader. This essay aims to question the generally accepted empowerment of Atwood’s Penelope and celebrates the murdered maids as the locus of emotion, where marginal aspects of gender and class merge to weave a powerful metaphorical tapestry of popular and traditionally feminized literary genres that, in plunging into and embracing the semiotic realm, ultimately solidify into an eclectic but compact alternative tradition of women’s writing and myth-making.

Measurements of absolute, single charge-exchange cross sections of H+, He+ and He2+ with H2O and CO2

Absolute measurements have been made of single-electron charge-exchange cross sections of H+, He+, and He2+ in H2O and CO2 in the energy range 0.3-7.5 keV amu(-1). Collisions of this type occur in the interaction of solar wind ions with cometary gases and have been observed by the Giotto spacecraft using the Ion Mass Spectrometer/High Energy Range Spectrometer (IMS/HERS) during a close encounter with comet Halley in 1986. Increases in the He+ ion density, and in the He2+ to H+ density ratio were reported by Shelley et al, and Fuselier et al. and were explained by charge exchange. However, the lack of reliable cross sections for this process made interpretation of the data difficult. New cross sections are presented and discussed in relation to the Giotto observations.