701 research outputs found

    The Technological Development of Minimally Invasive Spine Surgery

    Get PDF
    Minimally invasive spine surgery has its roots in the mid-twentieth century with a few surgeons and a few techniques, but it has now developed into a large field of progressive spinal surgery. A wide range of techniques are now called \ minimally invasive,\ and case reports are submitted constantly with new \ minimally invasive\ approaches to spinal pathology. As minimally invasive spine surgery has become more mainstream over the past ten years, in this paper we discuss its history and development. © 2014 Laura A. Snyder et al

    Análisis criptopaleontológico del lapidario de Teofrastro (s. III a.C.)

    Get PDF
    La obra"Perì líthon" o"Tratado de Piedras" de Teofrasto, es considerado el texto más antiguo conservado sobre minerales y rocas, aunque haya llegado hasta nosotros incompleto. En este trabajo se analiza su contenido comparándolo con el de otros lapidarios antiguos y se concluye que once de las piedras que refiere y que vienen indicadas con nombres geográficos o crípticos son fósiles de plantas, vertebrados o químicos. Por eso, esta obra debe considerarse también como el tratado más antiguo que conocemos sobre paleontología, pues además de los fósiles que menciona, en ella se alude expresamente al proceso de fosilización. Palabras clave: Criptopaleontología

    A Cryogenic Silicon Interferometer for Gravitational-wave Detection

    Get PDF
    The detection of gravitational waves from compact binary mergers by LIGO has opened the era of gravitational wave astronomy, revealing a previously hidden side of the cosmos. To maximize the reach of the existing LIGO observatory facilities, we have designed a new instrument that will have 5 times the range of Advanced LIGO, or greater than 100 times the event rate. Observations with this new instrument will make possible dramatic steps toward understanding the physics of the nearby universe, as well as observing the universe out to cosmological distances by the detection of binary black hole coalescences. This article presents the instrument design and a quantitative analysis of the anticipated noise floor

    Gravitational Waves From Known Pulsars: Results From The Initial Detector Era

    Get PDF
    We present the results of searches for gravitational waves from a large selection of pulsars using data from the most recent science runs (S6, VSR2 and VSR4) of the initial generation of interferometric gravitational wave detectors LIGO (Laser Interferometric Gravitational-wave Observatory) and Virgo. We do not see evidence for gravitational wave emission from any of the targeted sources but produce upper limits on the emission amplitude. We highlight the results from seven young pulsars with large spin-down luminosities. We reach within a factor of five of the canonical spin-down limit for all seven of these, whilst for the Crab and Vela pulsars we further surpass their spin-down limits. We present new or updated limits for 172 other pulsars (including both young and millisecond pulsars). Now that the detectors are undergoing major upgrades, and, for completeness, we bring together all of the most up-to-date results from all pulsars searched for during the operations of the first-generation LIGO, Virgo and GEO600 detectors. This gives a total of 195 pulsars including the most recent results described in this paper.United States National Science FoundationScience and Technology Facilities Council of the United KingdomMax-Planck-SocietyState of Niedersachsen/GermanyAustralian Research CouncilInternational Science Linkages program of the Commonwealth of AustraliaCouncil of Scientific and Industrial Research of IndiaIstituto Nazionale di Fisica Nucleare of ItalySpanish Ministerio de Economia y CompetitividadConselleria d'Economia Hisenda i Innovacio of the Govern de les Illes BalearsNetherlands Organisation for Scientific ResearchPolish Ministry of Science and Higher EducationFOCUS Programme of Foundation for Polish ScienceRoyal SocietyScottish Funding CouncilScottish Universities Physics AllianceNational Aeronautics and Space AdministrationOTKA of HungaryLyon Institute of Origins (LIO)National Research Foundation of KoreaIndustry CanadaProvince of Ontario through the Ministry of Economic Development and InnovationNational Science and Engineering Research Council CanadaCarnegie TrustLeverhulme TrustDavid and Lucile Packard FoundationResearch CorporationAlfred P. Sloan FoundationAstronom

    CAnceR IN PreGnancy (CARING) - a retrospective study of cancer diagnosed during pregnancy in the United Kingdom

    Get PDF
    BACKGROUND: The incidence of cancer diagnosed during pregnancy is increasing. Data relating to investigation and management, as well as maternal and foetal outcomes is lacking in a United Kingdom (UK) population.METHODS: In this retrospective study we report data from 119 patients diagnosed with cancer during pregnancy from 14 cancer centres in the UK across a five-year period (2016-2020).RESULTS: Median age at diagnosis was 33 years, with breast, skin and haematological the most common primary sites. The majority of cases were new diagnoses (109 patients, 91.6%). Most patients were treated with radical intent (96 patients, 80.7%), however, gastrointestinal cancers were associated with a high rate of palliative intent treatment (63.6%). Intervention was commenced during pregnancy in 68 (57.1%) patients; 44 (37%) had surgery and 31 (26.1%) received chemotherapy. Live births occurred in 98 (81.7%) of the cases, with 54 (55.1%) of these delivered by caesarean section. Maternal mortality during the study period was 20.2%.CONCLUSIONS: This is the first pan-tumour report of diagnosis, management and outcomes of cancer diagnosed during pregnancy in the UK. Our findings demonstrate proof of concept that data collection is feasible and highlight the need for further research in this cohort of patients.</p

    Behind the stiff upper lip: war narratives of older men with dementia.

    Get PDF
    The concept of the stiff upper lip stands as a cultural metaphor for the repression and figurative ¿biting back¿ of traumatic experience, particularly in military contexts. For men born in the first half of the 20th century, maintaining a stiff upper lip involved the ability to exert high levels of cognitive control over the subjective, visceral and emotional domains of experience. In the most common forms of dementia, which affect at least one in five men now in their 80s and 90s, this cognitive control is increasingly lost. One result is that, with the onset of dementia, men who have in the intervening years maintained a relative silence about their wartime experiences begin to disclose detailed memories of such events, in some cases for the first time. This article draws on narrative biographical data from three men with late-onset dementia who make extensive reference to their experience of war. The narratives of Sid, Leonard and Nelson are used to explore aspects of collective memory of the two World Wars, and the socially constructed masculinities imposed on men who grew up and came of age during those decades. The findings show that in spite of their difficulties with short term memory, people with dementia can contribute rich data to cultural studies research. Some aspects of the narratives discussed here may also be considered to work along the line of the counter-hegemonic, offering insights into lived experiences of war that have been elided in popular culture in the post-War years

    Urban groundwater quality in Africa : benefits and challenges

    Get PDF
    Most urban centres in Africa rely on groundwater, in Southern Africa it is estimated that at least 36% of the population relies on groundwater, this number is much larger for many other settlements in Africa. Urban water supplies are reliant on local groundwater sources to supply 25% of water use, from both private and public/municipal sources. Groundwater is important even in areas where groundwater abstraction is limited by low productivity groundwater stores such as those found in hard-rock settings (e.g. granites). Urban centres are a focus for a wide range of human activities past and present that can alter groundwater quality with potential impacts on subsequent groundwater uses. Once contaminated, groundwater can be challenging to clean up. Despite these challenges, groundwater is often of better quality compared to surface water alternatives in urban settings. Groundwater is generally well protected from surface contamination: as water percolates through the soil and deeper rock some contaminants (e.g. bacteria) may be removed. In contrast to surface water pollution, groundwater quality changes are often gradual, allowing scope for the problem to be assessed and interventions and adaptations to be planned and undertaken if recognised early. Even when groundwater is contaminated (e.g. by bacteria or organic contaminants) these are often detected at low concentrations. Compared to surface waters treatment, costs are often lower and simpler treatment solutions are possible due to the reduced pollution loads and fluctuations in groundwaters. Access to groundwater is widely dispersed compared to alternative sources (lakes, rivers and piped supplies). This offers a clear potential to expand groundwater use in many towns and cities to enhance water security (e.g. via public water supply, piped systems with standpipes, self-supply such as private wells and in some cases tankered or sachet groundwater)
    corecore