3,747 research outputs found

    Psychophysical measures of visual function and everyday perceptual experience in a case of congenital stationary night blindness

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    An appreciation of the relation between laboratory measures of visual deficit and everyday perceptual experience is fundamental to understanding the impact of a visual condition on patients and so to a fuller characterization of the disorder. This study aims to understand better the interpretative processes by which modified sensory information is perceived by a patient with congenital stationary night blindness and the adaptive strategies that are devised to deal with their measurable visual loss. Psychophysical measurements of temporal resolution, spectral sensitivity, and color discrimination were conducted on a 78-year-old male patient with the condition, who was also interviewed at length about the ways in which his diagnosis affected his daily life. Narrative analysis was employed to identify the relation between his subjective perceptual experiences and functional deficits in identifiable components of the visual system. Psychophysical measurements indicated a complete lack of rod perception and substantially reduced cone sensitivity. Two particular effects of this visual loss emerged during interviews: 1) the development of navigational techniques that relied on light reflections and point sources of light and 2) a reluctance to disclose the extent of visual loss and resulting lifelong psychosocial consequences. This study demonstrates the valuable complementary role that rich descriptive patient testimony can play, in conjunction with laboratory and clinical measurements, in more fully characterizing a disorder and in reaching a more complete understanding of the experience of vision loss. It also evidences the particular suitability of filmmaking techniques as a means of accessing and communicating subjective patient experience

    Production Scale Single-pass Corn Stover Large Square Baling Systems

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    A single-pass combine baler was operated in Central Iowa for the harvest of 2012 in a production scale setting. The combine’s performance was monitored with a telemetry data logger. The combine was able to harvest 2227 bushels (62.4 tons) of grain per hour on average and 18.8 tons of stover per hour on average. A complete quality analysis system was evaluated for the single-pass combine through the harvest of 2012. On board baler scales were tested showing a less than 1% difference in average weight between calibrated platform scales and the baler scales. Also, a microwave moisture meter was evaluated on a separate baler which showed between the 10% and 29% moisture level an R2 value of 87%

    Retinal Architecture in ​\u3cem\u3eRGS9-\u3c/em\u3e and ​\u3cem\u3eR9AP\u3c/em\u3e-Associated Retinal Dysfunction (Bradyopsia)

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    Purpose To characterize photoreceptor structure and mosaic integrity in subjects with RGS9- and R9AP-associated retinal dysfunction (bradyopsia) and compare to previous observations in other cone dysfunction disorders such as oligocone trichromacy. Design Observational case series. Methods setting: Moorfields Eye Hospital (United Kingdom) and Medical College Wisconsin (USA). study population: Six eyes of 3 subjects with disease-causing variants in RGS9 or R9AP. main outcome measures: Detailed retinal imaging using spectral-domain optical coherence tomography and confocal adaptive-optics scanning light ophthalmoscopy. Results Cone density at 100 μm from foveal center ranged from 123 132 cones/mm2to 140 013 cones/mm2. Cone density ranged from 30 573 to 34 876 cones/mm2 by 600 μm from center and from 15 987 to 16,253 cones/mm2 by 1400 μm from center, in keeping with data from normal subjects. Adaptive-optics imaging identified a small, focal hyporeflective lesion at the foveal center in both eyes of the subject with RGS9-associated disease, corresponding to a discrete outer retinal defect also observed on spectral-domain optical coherence tomography; however, the photoreceptor mosaic remained intact at all other observed eccentricities. Conclusions Bradyopsia and oligocone trichromacy share common clinical symptoms and cannot be discerned on standard clinical findings alone. Adaptive-optics imaging previously demonstrated a sparse mosaic of normal wave-guiding cones remaining at the fovea, with no visible structure outside the central fovea in oligocone trichromacy. In contrast, the subjects presented in this study with molecularly confirmed bradyopsia had a relatively intact and structurally normal photoreceptor mosaic, allowing the distinction between these disorders based on the cellular phenotype and suggesting different pathomechanisms

    Spectral Index of the Diffuse Radio Background Measured From 100 to 200 MHz

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    The mean absolute brightness temperature of the diffuse radio background was measured as a function of frequency in a continuous band between 100 and 200 MHz over an effective solid angle of ~pi str at high Galactic latitude. A spectral brightness temperature index of beta = 2.5 +/- 0.1 (alpha_s = 0.5) was derived from the observations, where the error limits are 3-sigma and include estimates of the instrumental systematics. Zenith drift scans with central declinations of -26.5 degrees and spanning right ascensions 0 to 10 hours yielded little variation in the mean spectral index. The mean absolute brightness temperature at 150 MHz was found to reach a minimum of T = 237 +/- 10 K at a right ascension of 2.5 hours. Combining these measurements with those of Haslam et al. 1982 yields a spectral index of beta = 2.52 +/- 0.04 between 150 and 408 MHz.Comment: 8 pages including 7 figures and 4 tables. Accepted by A

    Innovative regenerative medicines in the EU : a better future in evidence?

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    Background Despite a steady stream of headlines suggesting they will transform the future of healthcare, high-tech regenerative medicines have, to date, been quite inaccessible to patients; only eight have been granted an EU marketing licence in the last seven years. Here, we outline some of the historical reasons for this paucity of licensed innovative regenerative medicines. We discuss the challenges to be overcome to expedite the development of this complex and rapidly changing area of medicine, together with possible reasons to be more optimistic for the future. Discussion Several factors have contributed to the scarcity of cutting-edge regenerative medicines in clinical practice. These include the great expense and difficulties involved in planning how individual therapies will be developed, manufactured to commercial levels, and ultimately successfully delivered to patients. Specific challenges also exist when evaluating the safety, efficacy and cost-effectiveness of these therapies. Furthermore, many treatments are used without a licence from the EMA - under “Hospital Exemption” from the EC legislation. For products which are licensed, alternative financing approaches by healthcare providers may be needed, since many therapies will have significant up-front costs but uncertain benefits and harms in the long-term. However, increasing political interest and more flexible mechanisms for licensing and paying for therapies are now evident. These could be key to the future growth and development of regenerative medicine in clinical practice. Conclusions Recent developments in regulatory processes, coupled with increasing political interest may offer some hope for improvements to the long and often difficult routes from laboratory to marketplace for leading-edge cell or tissue therapies. Collaboration between publicly-funded researchers and the pharmaceutical industry could be key to the future development of regenerative medicine in clinical practice; such collaborations might also offer a possible antidote to the innovation crisis in the pharmaceutical industry

    Rapid iododeboronation with and without gold catalysis: application to radiolabelling of arenes

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    Radiopharmaceuticals incorporating radioactive iodine in combination with SPECT imaging play a key role in nuclear medicine, with applications in drug development and disease diagnosis. Despite this importance, there are relatively few general methods for incorporating radioiodine into small molecules. Here we describe a rapid, air- and moisture-stable ipso-iododeboronation procedure using NIS, in the non-toxic and green solvent dimethyl carbonate. The fast reaction and mild conditions of the gold-catalysed method led to the development of a highly efficient process for radiolabelling of arenes, which constitutes the first example of an application of homogenous gold catalysis to selective radiosynthesis. This has been exemplified with an effective synthesis of radiolabelled meta-[125I]iodobenzylguanidine, a radiopharmaceutical used for the imaging and therapy of human norepinephrine transporter-expressing tumours

    Anticipating the clinical adoption of regenerative medicine : building institutional readiness in the UK

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    This perspective paper examines the challenges of implementing regenerative medicine (RM) therapies within hospitals and clinics. Drawing on recent work in the social sciences, the paper highlights dynamics within existing healthcare systems that will present both hindrances and affordances for the implementation of new RM technologies within hospitals and clinics. The paper argues that identifying suitable locations for cell- and gene-therapy treatment centers requires an assessment of their institutional readiness for RM. Some provisional criteria for assessing institutional readiness are outlined, and the paper will suggest that it is necessary to begin developing a program for the phased introduction of RM in the longer ter

    Changes in metal leachability through stimulation of iron reducing communities within waste sludge

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    Bioreduction of ferric iron-rich wastes is a rapidly emerging technology for the extraction/ recovery of metals from low-grade ores and metallurgical wastes. However, despite studies being successful, they have only been demonstrated at laboratory scale and issues relating to economic, industrial scale application have yet to be studied. Using bioreduction as a pre-treatment to increase recovery yield is a relatively new concept. This study examines the biostimulation of microbial communities to induce bioreduction of metalliferous sludge and the effect that this has on the leachability of metals from the waste using dilute sulphuric acid. Data shows an increase in both zinc and copper leachability after bioreduction, with maximum six fold and eleven fold increase (compared to pre-treatment) in the amount of zinc and copper leached respectively.</jats:p
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