32 research outputs found

    Using Light to Improve Commercial Value

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    The plasticity of plant morphology has evolved to maximize reproductive fitness in response to prevailing environmental conditions. Leaf architecture elaborates to maximize light harvesting, while the transition to flowering can either be accelerated or delayed to improve an individual's fitness. One of the most important environmental signals is light, with plants using light for both photosynthesis and as an environmental signal. Plants perceive different wavelengths of light using distinct photoreceptors. Recent advances in LED technology now enable light quality to be manipulated at a commercial scale, and as such opportunities now exist to take advantage of plants' developmental plasticity to enhance crop yield and quality through precise manipulation of a crops' lighting regime. This review will discuss how plants perceive and respond to light, and consider how these specific signaling pathways can be manipulated to improve crop yield and quality

    Colour assessment outcomes – a new approach to grading the severity of color vision loss

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    INTRODUCTION: Recent studies have shown that a significant percentage of subjects with anomalous, congenital trichromacy can perform the suprathreshold, colour-related tasks encountered in many occupations with the same accuracy as normal trichromats. In the absence of detailed, occupation-specific studies, an alternative approach is to make use of new findings and the statistical outcomes of past practices that have been considered safe to produce graded, justifiable categories of colour vision that can be enforced. METHODS: We analyzed traditional color assessment outcomes and measured severity of colour vision loss using the CAD test in 1363 subjects (336 normals, 705 deutan, 319 protan and 3 tritan). The severity of colour vision loss was measured in each subject and statistical, pass / fail outcomes established for each of the most commonly used, conventional colour assessment tests and protocols. RESULTS: The correlation between the number of Ishihara (IH) test plates subjects fail and the severity of RG colour vision loss was very poor. The 38 plates IH test has high sensitivity when no errors are allowed (i.e., only 0.71% deutans and 0.63% protans pass). Protocols based on zero errors are uncommon since 18.15% of normal trichromats fail. The most common protocols employ either the 24 or the 14 plates editions with two or less errors. These protocols pass almost all normal trichromats, but the deutans and some protans that also pass (when two or less errors are allowed) can be severely deficient. This is simply because the most challenging plates have not been included in the 24 and 14 plates editions. As a result, normals no longer fail, but the deutans and protans that pass have more severe loss of colour vision since they fail less challenging plates. The severity of colour vision loss was measured in each subject and statistical, pass / fail outcomes established for each of the most commonly used, conventional colour assessment tests and protocols. DISCUSSION: Historical evidence and new findings that relate severity of loss to the effective use of colour signals in a number of tasks provide the basis for a new colour grading system based on six categories. A single colour assessment test is needed to establish the applicant’s Colour Vision category which can range from ‘supernormal’ (CV0), for the most stringent, colour-demanding tasks, to ‘severe colour deficiency’, when red / green colour vision is either absent or extremely weak (CV5)

    Benign external hydrocephalus: a review, with emphasis on management

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    Benign external hydrocephalus in infants, characterized by macrocephaly and typical neuroimaging findings, is considered as a self-limiting condition and is therefore rarely treated. This review concerns all aspects of this condition: etiology, neuroimaging, symptoms and clinical findings, treatment, and outcome, with emphasis on management. The review is based on a systematic search in the Pubmed and Web of Science databases. The search covered various forms of hydrocephalus, extracerebral fluid, and macrocephaly. Studies reporting small children with idiopathic external hydrocephalus were included, mostly focusing on the studies reporting a long-term outcome. A total of 147 studies are included, the majority however with a limited methodological quality. Several theories regarding pathophysiology and various symptoms, signs, and clinical findings underscore the heterogeneity of the condition. Neuroimaging is important in the differentiation between external hydrocephalus and similar conditions. A transient delay of psychomotor development is commonly seen during childhood. A long-term outcome is scarcely reported, and the results are varying. Although most children with external hydrocephalus seem to do well both initially and in the long term, a substantial number of patients show temporary or permanent psychomotor delay. To verify that this truly is a benign condition, we suggest that future research on external hydrocephalus should focus on the long-term effects of surgical treatment as opposed to conservative management

    A review of the current treatment methods for posthaemorrhagic hydrocephalus of infants

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    Posthaemorrhagic hydrocephalus (PHH) is a major problem for premature infants, generally requiring lifelong care. It results from small blood clots inducing scarring within CSF channels impeding CSF circulation. Transforming growth factor – beta is released into CSF and cytokines stimulate deposition of extracellular matrix proteins which potentially obstruct CSF pathways. Prolonged raised pressures and free radical damage incur poor neurodevelopmental outcomes. The most common treatment involves permanent ventricular shunting with all its risks and consequences

    Do antiepileptic drugs differ in suppressing interictal epileptiform activity in children?

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    Antiepileptic drugs may suppress interictal epileptiform activity in addition to suppressing seizures, although the comparative rates of suppression of interictal epileptiform activity for phenobarbital (PHB), carbamazepine (CBZ), and valproate (VPA) in children are unknown. Electroencephalogram (EEG) pairs were identified in which the first tracing illustrated interictal epileptiform activity before antiepileptic drug treatment; the rate of clearance of such activity in the subsequent tracing was assessed according to the drug introduced. EEG pairs (n = 213) were identified for CBZ, PHB, and VPA. Overall suppression rates of epileptiform activity in the second EEG were 12/55 (22%) for PHB, 27/81 (33%) for CBZ, and 35/77 (46%) for VPA (P = 0.005 for VPA vs PHB). When suppression rates were assessed comparing sleep-state pairs, suppression rates were 24/80 (30%) for PHB, 51/129 (40%) for CBZ, and 60/120 (50%) for VPA (P = 0.005 for PHB vs VPA). A subanalysis for focal discharges yielded suppression rates of 10/43 (23%) for PHB, 19/60 (32%) for CBZ, and 8/19 (42%) for VPA; for generalized discharges, 2/12 (17%) for PHB, 8/21 (38%) for CBZ, and 27/58 (47%) for VPA. VPA, and to a lesser extent CBZ, appeared superior to PHB in suppressing interictal epileptiform activity, including both focal and generalized epileptiform activity. (C) 2001 by Elsevier Science Inc. All rights reserved

    Experience with rufinamide in a pediatric population: a single center\u27s experience.

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    Rufinamide is a new antiepileptic drug recently approved as adjunctive treatment for generalized seizures in Lennox-Gastaut syndrome. We undertook a retrospective analysis of 77 patients with refractory epilepsy and receiving rufinamide to evaluate the drug\u27s efficacy, tolerability, safety, and dosing schedules. It appeared efficacious in diverse epilepsy syndromes, with the highest responder rate in focal cryptogenic epilepsies (81.1% of patients with \u3e50% response rate), and in diverse seizure types, with the highest responder rate in tonic/atonic and partial seizures (48.6% and 46.7% of patients with \u3e50% response rate, respectively). Rufinamide was well tolerated: only 13% of patients developed side effects necessitating drug withdrawal. These findings suggest that rufinamide may possess good efficacy and tolerability, and that its efficacy may extend to epilepsy syndromes beyond Lennox-Gastaut, including both partial and generalized epilepsy syndromes
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