933 resultados para Form phenol sulfotransferases
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Purpose: In animal models hemi-field deprivation results in localised, graded vitreous chamber elongation and presumably deprivation induced localised changes in retinal processing. The aim of this research was to determine if there are variations in ERG responses across the retina in normal chick eyes and to examine the effect of hemi-field and full-field deprivation on ERG responses across the retina and at earlier times than have previously been examined electrophysiologically. Methods: Chicks were either untreated, wore monocular full-diffusers or half-diffusers (depriving nasal retina) (n = 6-8 each group) from day 8. mfERG responses were measured using the VERIS mfERG system across the central 18.2º× 16.7º (H × V) field. The stimulus consisted of 61 unscaled hexagons with each hexagon modulated between black and white according to a pseudorandom binary m-sequence. The mfERG was measured on day 12 in untreated chicks, following 4 days of hemi-field diffuser wear, and 2, 48 and 96 h after application of full-field diffusers. Results: The ERG response of untreated chick eyes did not vary across the measured field; there was no effect of retinal location on the N1-P1 amplitude (p = 0.108) or on P1 implicit time (p > 0.05). This finding is consistent with retinal ganglion cell density of the chick varying by only a factor of two across the entire retina. Half-diffusers produced a ramped retina and a graded effect of negative lens correction (p < 0.0001); changes in retinal processing were localized. The untreated retina showed increasing complexity of the ERG waveform with development; form-deprivation prevented the increasing complexity of the response at the 2, 48 and 96 h measurement times and produced alterations in response timing. Conclusions: Form-deprivation and its concomitant loss of image contrast and high spatial frequency images prevented development of the ERG responses, consistent with a disruption of development of retinal feedback systems. The characterisation of ERG responses in normal and deprived chick eyes across the retina allows the assessment of concurrent visual and retinal manipulations in this model. (Ophthalmic & Physiological Optics © 2013 The College of Optometrists.)
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Intravitreal injections of GABA antagonists, dopamine agonists and brief periods of normal vision have been shown separately to inhibit form-deprivation myopia (FDM). Our study had three aims: (i) establish whether GABAergic agents modify the myopia protective effect of normal vision, (ii) investigate the receptor sub-type specificity of any observed effect, and (iii) consider an interaction with the dopamine (DA) system. Prior to the period of normal vision GABAergic agents were applied either (i) individually, (ii) in combination with other GABAergic agents (an agonist with an antagonist), or (iii) in combination with DA agonists and antagonists. Water injections were given to groups not receiving drug treatments so that all experimental eyes received intravitreal injections. As shown previously, constant form-deprivation resulted in high myopia and when diffusers were removed for 2 h per day the period of normal vision greatly reduced the FDM that developed. GABA agonists inhibited the protective effect of normal vision whereas antagonists had the opposite effect. GABAA/C agonists and D2 DA antagonists when used in combination were additive in suppressing the protective effect of normal vision. A D2 DA agonist restored some of the protective effect of normal vision that was inhibited by a GABA agonist (muscimol). The protective effect of normal vision against form-deprivation is modifiable by both the GABAergic and DAergic pathways.
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This book analyses the structure, form and language of a selected number of international and national legal instruments and reviews how an illustrative range of international and national judicial institutions have responded to the issues before them and the processes of legal reasoning engaged by them in reaching their decisions. This involves a very detailed discussion of these primary sources of international and national environmental law with a view to determining their jurisprudential architecture and the processes of reasoning expected of those responsible for implementing these architectural arrangements. This book is concerned not with the effectiveness or the quality of an environmental legal system but only with its jurisprudential characteristics and their associated processes of legal reasoning.
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Background High-risk foot complications such as neuropathy, ischaemia, deformity, infections, ulcers and amputations consume considerable health care resources and typically result from chronic diseases. This study aimed to develop and test the validity and reliability of a Queensland High Risk Foot Form (QHRFF) tool. Methods Phase one involved developing a QHRFF using an existing diabetes high-risk foot tool, literature search, expert panel and several state-wide stakeholder groups. Phase two tested the criterion-related validity along with inter- and intra-rater reliability of the final QHRFF. Three cohorts of patients (n = 94) and four clinicians, representing different levels of expertise, were recruited. Validity was determined by calculating sensitivity, specificity and positive predictive values (PPV). Kappa and intra-class correlation (ICC) statistics were used to establish reliability. Results A QHRFF tool containing 46-items across seven domains was developed and endorsed. The majority of QHRFF items achieved moderate-to-perfect validity (PPV = 0.71 – 1) and reliability (Kappa/ICC = 0.41 – 1). Items with weak validity and/or reliability included those identifying health professionals previously attending the patient, other (non-listed) co-morbidity, previous foot ulcer, foot deformity, optimum offloading and optimum footwear. Conclusions The QHRFF had moderate-to-perfect validity and reliability across the majority of items, particularly identifying individual co-morbidities and foot complications. Items with weak validity or reliability need to be re-defined or removed. Overall, the QHRFF appears to be a valid and reliable tool to assess, collect and measure clinical data pertaining to high-risk foot complications for clinical or research purposes.
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Background: People often modify oral solid dosage forms when they experience difficulty swallowing them. Modifying dosage forms may cause adverse effects to the patient, and the person undertaking the modification. Pharmacists are often the first point of contact for people in the general community seeking advice regarding medications. Nurses are at the forefront of administering medications to patients and are likely to be most directly affected by a patient’s swallowing ability, while general practitioners (GPs) are expected to consider swallowing abilities when prescribing medications. Objective: To compare the perspectives and experiences of GPs, pharmacists, and nurses regarding medication dosage form modification and their knowledge of medication modification. Method: Questionnaires tailored to each profession were posted to 630 GPs, and links to an online version were distributed to 2,090 pharmacists and 505 nurses. Results: When compared to pharmacists and GPs, nurses perceived that a greater proportion of the general community modified solid dosage forms. Pharmacists and GPs were most likely to consider allergies and medical history when deciding whether to prescribe or dispense a medicine, while nurses’ priorities were allergies and swallowing problems when administering medications. While nurses were more likely to ask their patients about their ability to swallow medications, most health professionals reported that patients “rarely” or “never” volunteered information about swallowing difficulties. The majority of health professionals would advise a patient to crush or split noncoated non-sustained-release tablets, and would consult colleagues or reference sources for sustained-release or coated tablets. Health professionals appeared to rely heavily upon the suffix attached to medication names (which suggest modified release properties) to identify potential problems associated with modifying medications. Conclusion: The different professional roles and responsibilities of GPs, pharmacists, and nurses are associated with different perspectives of, and experiences with, people modifying medications in the general community and knowledge about consequences of medication modification.
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It is well established that literary work can promote insights that result in future change, whether on a personal or an institutional level. As Umberto Eco (1989) notes, the act of reading does not stop with the artist but continues into the work of communities. The papers delivered in this panel consider the regenerative role of literature within culture, arguing that the special properties of literature can convey an important sense of nature (Bateson 1973, Zapf 2008). These concepts are discussed in relation to writing about Australian flora and fauna. Using an ecocritical focus based on ideas about the relationship between literature and the environment the paper considers Australian works and the way in which literature enlivens this complex intersection between humans, animals and the environment. This engagement is investigated through three modes: the philosophical, the literary, and the practical. The novels discussed include Alexis Wright’s Carpentaria, Richard Flanagan’s Wanting, and Sonya Hartnett’s Forest, as well as a range of fictional and non-fictional works that describe the Blue Mountains region in New South Wales. The paper closes with a discussion of the role of story-telling as a way of introducing the public to specific environmental locations and issues.
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This paper will examine the idea of the fold arid its assimilation into architecture through philosophy and mathematics. In all its iterations, the fold appears as two constitutive items: the fold as self-similarity, which implies recursion; the fold within the fold, and in turn, the fold as continuous discontinuity. The persistence of this conception of die fold will be demonstrated through a discussion of Leibniz's Monadology, Deleuze's Le Pli, and some mathematical ideas from catastrophe and chaos theory. This raises the issue of continuity between disciplines and thus the philosophical status this confers on the fold.
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By presenting the past as a repository of the characteristics of urban formation, urban morphology utilizes a knowledge platform as the basis for interpretation of accordant architectural responses (Levy, 1999). Operating within this framework at the scale of architectural features of individual buildings, and imbued with reference to the intrinsic architectural elements of both preceding and existing building forms, micro-morphology (Larkham, 2006, p. 126) provides the efficacy for new architecture that emerges from such a manner of composition...
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Heparan sulfate proteoglycans cooperate with basic fibroblast growth factor (bFGF/FGF2) signaling to control osteoblast growth and differentiation, as well as metabolic functions of osteoblasts. FGF2 signaling modulates the expression and activity of Runt-related transcription factor 2 (Runx2/Cbfa1), a key regulator of osteoblast proliferation and maturation. Here, we have characterized novel Runx2 target genes in osteoprogenitors under conditions that promote growth arrest while not yet permitting sustained phenotypic maturation. Runx2 enhances expression of genes related to proteoglycan-mediated signaling, including FGF receptors (e.g., FGFR2 and FGFR3) and proteoglycans (e.g., syndecans [Sdc1, Sdc2, Sdc3], glypicans [Gpc1], versican [Vcan]). Runx2 increases expression of the glycosyltransferase Exostosin-1 (Ext1) and heparanase, as well as alters the relative expression of N-linked sulfotransferases (Ndst1 = Ndst2 > Ndst3) and enzymes mediating O-linked sulfation of heparan sulfate (Hs2st > Hs6st) or chondroitin sulfate (Cs4st > Cs6st). Runx2 cooperates with FGF2 to induce expression of Sdc4 and the sulfatase Galns, but Runx2 and FGF2 suppress Gpc6, thus suggesting intricate Runx2 and FGF2 dependent changes in proteoglycan utilization. One functional consequence of Runx2 mediated modulations in proteoglycan-related gene expression is a change in the responsiveness of bone markers to FGF2 stimulation. Runx2 and FGF2 synergistically enhance osteopontin expression (>100 fold), while FGF2 blocks Runx2 induction of alkaline phosphatase. Our data suggest that Runx2 and the FGF/proteoglycan axis may form an extracellular matrix (ECM)-related regulatory feed-back loop that controls osteoblast proliferation and execution of the osteogenic program.
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Recently, several classes of permutation polynomials of the form (x2 + x + δ)s + x over F2m have been discovered. They are related to Kloosterman sums. In this paper, the permutation behavior of polynomials of the form (xp − x + δ)s + L(x) over Fpm is investigated, where L(x) is a linearized polynomial with coefficients in Fp. Six classes of permutation polynomials on F2m are derived. Three classes of permutation polynomials over F3m are also presented.
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Smart Material Interface (SMI) is the latest generation of user interface that makes use of engineered materials and leverages their special properties. SMIs are capable of changing their physical properties such as shape, size and color, and can be controlled under certain (external) conditions. We provide an example of such an SMI in the form of a prototype of a vacuum cleaner. The prototype uses schematic electrochromic polymer at the suction nozzle of the vacuum cleaner, which changes its color depending on the dust level on a floor. We emphasize on the new affordances and communication language supported by SMIs, which challenges the current metaphors of user interfaces in the field of HCI.
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Capture of an electron by tetracyanoethylene oxide can initiate a number of decomposition pathways. One of these decompositions yields [(NC)3C]− as the ionic product. Ab initio calculations (at the B3LYP/6-31+G∗ level of theory) indicate that the formation of [(NC)3C]− is initiated by capture of an electron into the LUMO of tetracyanoethylene oxide to yield the anion radical [(NC)2C–O–C(CN)2]−· that undergoes internal nucleophilic substitution to form intermediate [(NC)3C–OCCN]−·. This intermediate dissociates to form [(NC)3C]− (m/z 90) as the ionic product. The radical (NC)3C· has an electron affinity of 4.0 eV (385 kJ mol−1). Ab initio calculations show that [(NC)3C]− is trigonal planar with the negative charge mainly on the nitrogens. A pictorial representation of this structure is the resonance structure formed from three degenerate contributing structures (NC)2–CCN−. The other product of the reaction is nominally (NCCO)·, but there is no definitive experimental evidence to indicate whether this radical survives intact, or decomposes to NC· and CO. The overall process [(NC)2C–O–C(CN)2]−· → [(NC)3C]− + (NCCO)· is calculated to be endothermic by 21 kJ mol−1 with an overall barrier of 268 kJ mol−1.
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The respective requirements of collagen and MT1-MMP in the activation of MMP-2 by primary fibroblast cultures were explored further. Three-dimensional gels enriched in human collagen types I and III or composed of recombinant human type II or III collagen, caused increased MT1-MMP production (mRNA and protein) and induced MMP-2 activation. Only marginal induction was seen with dried monomeric collagen confirming the need for collagen fibrillar organisation for activation. To our surprise, relatively low amounts (as low as 25 μg/ml) of acid soluble type I collagen added to fibroblast cultures also induced potent MMP-2 activation. However, the requirement for collagen fibril formation by the added collagen was indicated by the inhibition seen when the collagen was pre-incubated with a fibril-blocking peptide, and the reduced activation seen with alkali-treated collagen preparations known to have impaired fibrilisation. Pre-treatment of the collagen with sodium periodate also abrogated MMP-2 activation induction. Further evidence of the requirement for collagen fibril formation was provided by the lack of activation when type IV collagen, which does not form collagen fibrils, was added in the cultures. Fibroblasts derived from MT1-MMP-deficient mice were unable to activate MMP-2 in response to either three-dimensional collagen gel or added collagen solutions, compared to their littermate controls. Collectively, these data indicate that the fibrillar structure of collagen and MT1-MMP are essential for the MMP-2 activational response in fibroblasts.
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A significant number of privatizations utilized to operate and maintain critical networked infrastructures have failed to meet contractual expectations and the expectations of the community. The author carried out empirical research ex-ploring four urban water systems. This research revealed that of the four forms of privatization the alliance form was particularly suited to the stewardship of an ur-ban water system. The question then is whether these findings from urban water can be generalised to O&M of infrastructure generally. The answer is increasingly important as governments seek financial sustainability through reapplying the contestability strategy and outsource and privatise further services and activities. This paper first examines the issues encountered with O & M privatisations. Second the findings as to the stewardship achieved by the four case study water systems are unpacked with particular focus upon the alliance form. Third the key variables which were found to have distinct causal links to the stewardship-like behaviour of the private participants in the Alliance case study are described. Fourth the variables which may be crucial to the successful application of the alliance form to the broader range of infrastructures are separated out. Fifth this paper then sets the path for research into these crucial features of the alliance form.