1,263 research outputs found
CHANGES OVER TIME IN PERCEPTIONS OF SPECIES VALUE: THE CASE OF AUSTROPOTAMOBIUS PALLIPES IN WALES
The perception of “value” placed on a species, here Austropotamobius pallipes, is related both to its conservation significance as well as economic social and legislative factors. Although the species may have had culinary significance in monastic Britain of the Middle Ages, there is no written record of its presence in Wales until the late eighteenth century. We know that before it was protected by law, it was collected for annual “crayfish feasts” into the twentieth century at a school on the River Usk. The rapid decline in the late twentieth century of this animal with full British and European legislative protection rekindled at least scientific interest in its survival. Currently funding for its survival comes mainly from EU sources
Reviews
Review of Jurisdiction under the Industrial Relations Act 1973: Some Problems and Issues, Employment: Towards an Active Employment Policy, Labor in the American Economy, Strikes and Participation, Democracy in the Work Place
Photoelectron diffraction: from phenomenological demonstration to practical tool
The potential of photoelectron diffraction—exploiting the coherent interference of directly-emitted and elastically scattered components of the photoelectron wavefield emitted from a core level of a surface atom to obtain structural information—was first appreciated in the 1970s. The first demonstrations of the effect were published towards the end of that decade, but the method has now entered the mainstream armoury of surface structure determination. This short review has two objectives: First, to outline the way that the idea emerged and the way this evolved in my own collaboration with Neville Smith and his colleagues at Bell Labs in the early years: Second, to provide some insight into the current state-of-the art in application of (scanned-energy mode) photoelectron diffraction to address two key issue in quantitative surface structure determination, namely, complexity and precision. In this regard a particularly powerful aspect of photoelectron diffraction is its elemental and chemical-state specificity
Engineering molecular chains in carbon nanotubes
A range of mono- and bis-functionalised fullerenes have been synthesised and inserted into single-walled carbon nanotubes. The effect of the size and shape of the functional groups of the fullerenes on the resultant 1D arrays formed within the nanotubes was investigated by high resolution transmission electron microscopy and X-ray diffraction. The addition of non-planar, sterically bulky chains to the fullerene cage results in highly ordered 1D structures in which the fullerenes are evenly spaced along the internal nanotube cavity. Theoretical calculations reveal that the functional groups interact with neighbouring fullerene cages to space the fullerenes evenly within the confines of the nanotube. The addition of two functional groups to opposite sides of the fullerene cages results in a further increase in the separation of the fullerene cages within the nanotubes at the cost of lower nanotube filling rates.This work was financially supported by FWF project I83-N20 (ESF IMPrESS), the Royal Society, the European Research Council (ERC), "Fundacao para a Ciencia ea Tecnologia" through the program Ciencia 2008, the project SeARCH (Services and Advanced Research Computing with HTC/HPC clusters) and Nottingham Nanoscience and Nanotechnology Centre (NNNC)
Impaired Communication Between the Motor and Somatosensory Homunculus Is Associated With Poor Manual Dexterity in Autism Spectrum Disorder
ABSTRACTBackgroundFine motor skill impairments are common in autism spectrum disorder (ASD), significantly affecting quality of life. Sensory inputs reaching the primary motor cortex (M1) from the somatosensory cortex (S1) are likely involved in fine motor skill and specifically motor learning. However, the role of these connections has not been directly investigated in humans. This study aimed to investigate, for the first time, the role of the S1-M1 connections in healthy subjects in vivo and whether microstructural alterations are associated with motor impairment in ASD.MethodsSixty right-handed neurotypical adult men aged 18 to 45 years, and 60 right-handed age- and sex-matched subjects diagnosed with ASD underwent fine motor skill assessment and scanning with diffusion tensor imaging (DTI). The streamlines of the hand region connecting S1-M1 of the motor-sensory homunculus were virtually dissected using TrackVis, and diffusion properties were extracted. The face/tongue region connections were used as control tracts.ResultsThe ASD group displayed lower motor performances and altered DTI measurements of the hand-region connection. Behavioral performance correlated with hand-region DTI measures in both groups, but not with the face/tongue connections, indicating anatomical specificity. There was a left-hemisphere association of motor ability in the control group and an atypical rightward shift in the ASD group.ConclusionsThese findings suggest that direct interaction between S1 and M1 may contribute to the human ability to precisely interact with and manipulate the environment. Because electrophysiological evidence indicates that these connections may underpin long-term potentiation in M1, our findings may lead to novel therapeutic treatments for motor skill disorders
From Phineas Gage and Monsieur Leborgne to H.M.: Revisiting Disconnection Syndromes
On the 50th anniversary of Norman Geschwind's seminal paper entitled 'Disconnexion syndrome in animal and man', we pay tribute to his ideas by applying contemporary tractographymethods to understand whitematter disconnection in 3 classic cases that made history in behavioral neurology.We first documented the locus and extent of the brain lesion from the computerized tomography of Phineas Gage's skull and themagnetic resonance images of Louis Victor Leborgne's brain, Broca's first patient, and Henry Gustave Molaison. We then applied the reconstructed lesions to an atlas of white matter connections obtained from diffusion tractography of 129 healthy adults. Our results showed that in all 3 patients, disruption extended to connections projecting to areas distant from the lesion.We confirmed that the damaged tracts link areas that in contemporary neuroscience are considered functionally engaged for tasks related to emotion and decision-making (Gage), language production (Leborgne), and declarative memory (Molaison). Our findings suggest that even historic cases should be reappraised within a disconnection framework whose principles were plainly established by the associationist schools in the last 2 centuries
Incorporating high-resolution demand and techno-economic optimization to evaluate micro-grids into the Open Source Spatial Electrification Tool (OnSSET)
For decades, electrification planning in the developing world has often focused on extending the national grid to increase electricity access. This article draws attention to the potential complementary role of decentralized alternatives – primarily micro-grids – to address universal electricity access targets. To this aim, we propose a methodology consisting of three steps to estimate the LCOE and to size micro-grids for large-scale geo-spatial electrification modelling. In the first step, stochastic load demand profiles are generated for a wide range of settlement archetypes using the open-source RAMP model. In the second step, stochastic optimization is carried by the open-source MicroGridsPy model for combinations of settlement size, load demand profiles and other important techno-economic parameters influencing the LCOE. In the third step, surrogate models are generated to automatically evaluate the LCOE using a multivariate regression of micro-grid optimization results as a function of influencing parameters defining each scenario instance. Our developments coupled to the OnSSET electrification tool reveal an important increase in the cost-competitiveness of micro-grids compared to previous analyses
Craniodental Affinities of Southeast Asia\u27s Negritos and the Concordance with Their Genetic Affinities
Genetic research into Southeast Asia\u27s negritos has revealed their deep-rooted ancestry, with time depth comparable to that of Southwest Pacific populations. This finding is often interpreted as evidence that negritos, in contrast to other Southeast Asians, can trace much of their ancestry directly back to the early dispersal of Homo sapiens in the order of 70 kya from Africa to Pleistocene New Guinea and Australia. One view on negritos is to lump them and Southwest Pacific peoples into an Australoid race whose geographic distribution had included Southeast Asia prior to the Neolithic incursion of Mongoloid farmers. Studies into Semang osteology have revealed some hints of Southwest Pacific affinities in cranial shape, dental morphology, and dental metrical shape. On the other hand, the Andamanese have been shown to resemble Africans in their craniometrics and South Asians in their dental morphology, while Philippine negritos resemble Mongoloid Southeast Asians in these respects and also in their dental metrics. This study expands the scope of negrito cranial comparisons by including Melayu Malays and additional coverage of South Asians. It highlights the distinction between the Mongoloid-like Philippine negritos and the Andamanese and Semang (and Senoi of Malaya) with their non-Mongoloid associations. It proposes that the early/mid-Holocene dispersal of the B4a1a mitochondrial DNA clade across Borneo, the Philippines, and Taiwan may be important for understanding the distinction between Philippine and other negritos
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