71 research outputs found
Recommended from our members
Relationship between early development of spelling and reading
The research reported in this thesis examined the relationship between beginning spelling and reading. More specifically, it focussed on the relationship between the development of early reading and spelling in a context where the approach to early reading instruction includes systematic phonological awareness and decoding instruction. A critical assumption made by proponents of developmental early literacy models is that transfer of skills and knowledge from reading to spelling will occur spontaneously and without formal instruction (Frith, 1980). By contrast instruction-centred approaches make the assumption that there are critical pre-requisite skills that can and should be taught explicitly (Carnine, Silbert & Kameenui, 1997). The difference between these approaches is highlighted in the treatment of invented spelling, a popular activity in Western Australian junior primary classes. A series of studies was undertaken to examine the effect on invented and standard spelling performance of teaching Year 1 children phonological awareness and the strategy of sounding out words. Data were gathered from a range of settings using different research tools. The relationship between phonological awareness and beginning reading and spelling performance was explored initially through a single case study. A post-hoc study was then undertaken with a cohort of students who had received systematic decoding instruction to examine whether proficiency in the decoding of nonwords was related to spelling performance. This permitted an analysis of common sub-skills of decoding and encoding. In the main study the effect on different aspects of reading and spelling performance of using Let\u27s Decode, an approach that includes explicit phonological awareness and systematic decoding instruction, was investigated. In addition, an analysis was made of whether students who received explicit instruction in skills known to contribute to beginning reading and spelling produced superior invented spelling samples. A qualitative analysis was made of the. pre and post invented spelling tests of two pairs of students from the control and intervention groups matched on invented spelling and phonological awareness skills at the beginning of the year, and re tested at the end of Year 1. The final research question involved a single-subject research design to examine the effect of explicit instruction in isolating phonemes in words and prompts to \u27listen for sounds\u27 prior to, and during, the process of spelling words. The single case study revealed a child who was regarded as a competent speller and reader but who could only read words in a familiar context and who had developed a strategy for spelling words based on copying an adult model. This was interpreted as evidence supporting the need for phonological awareness instruction as a pre-requisite for spelling. The post-hoc analysis of a class of students who had received systematic decoding instruction showed that no student classified as a \u27good decoder\u27 could also be classified as a \u27poor speller\u27. This result was considered evidence of a strong link between the phonological knowledge that is required to decode and the role of alphabetic knowledge in spelling. The main study revealed phonological awareness and systematic decoding instruction was associated with superior invented and conventional spelling and reading performance on all reading and spelling measures. Of particular importance was the finding that students who commenced the study with very weak phonological awareness and who subsequently received systematic phonological and decoding instruction showed greater gains in invented spelling than matched students in the control condition. The single subject design showed the effectiveness of phonological awareness individualised instruction on invented spelling for weak students from both intervention and control conditions. It was concluded that the ability to invent spelling is improved when students receive explicit instruction in phonological awareness and systematic decoding but that some students, namely those with persistent weakness in phonological awareness, also require explicit prompts to apply their alphabetic knowledge to spelling words. The implications for instruction of these findings are discussed
Autoimmune and autoinflammatory mechanisms in uveitis
The eye, as currently viewed, is neither immunologically ignorant nor sequestered from the systemic environment. The eye utilises distinct immunoregulatory mechanisms to preserve tissue and cellular function in the face of immune-mediated insult; clinically, inflammation following such an insult is termed uveitis. The intra-ocular inflammation in uveitis may be clinically obvious as a result of infection (e.g. toxoplasma, herpes), but in the main infection, if any, remains covert. We now recognise that healthy tissues including the retina have regulatory mechanisms imparted by control of myeloid cells through receptors (e.g. CD200R) and soluble inhibitory factors (e.g. alpha-MSH), regulation of the blood retinal barrier, and active immune surveillance. Once homoeostasis has been disrupted and inflammation ensues, the mechanisms to regulate inflammation, including T cell apoptosis, generation of Treg cells, and myeloid cell suppression in situ, are less successful. Why inflammation becomes persistent remains unknown, but extrapolating from animal models, possibilities include differential trafficking of T cells from the retina, residency of CD8(+) T cells, and alterations of myeloid cell phenotype and function. Translating lessons learned from animal models to humans has been helped by system biology approaches and informatics, which suggest that diseased animals and people share similar changes in T cell phenotypes and monocyte function to date. Together the data infer a possible cryptic infectious drive in uveitis that unlocks and drives persistent autoimmune responses, or promotes further innate immune responses. Thus there may be many mechanisms in common with those observed in autoinflammatory disorders
Improving adherence to glaucoma medication: a randomised controlled trial of a patient-centred intervention (The Norwich Adherence Glaucoma Study)
Background Improving adherence to ocular hypertension (OH)/glaucoma therapy is highly likely to prevent or reduce progression of optic nerve damage. The present study used a behaviour change counselling intervention to determine whether education and support was beneficial and cost-effective in improving adherence with glaucoma therapy. Methods A randomised controlled trial with a 13-month recruitment and 8-month follow-up period was conducted. Patients with OH/glaucoma attending a glaucoma clinic and starting treatment with travoprost were approached. Participants were randomised into two groups and adherence was measured over 8 months, using an electronic monitoring device (Travalert® dosing aid, TDA). The control group received standard clinical care, and the intervention group received a novel glaucoma education and motivational support package using behaviour change counselling. Cost-effectiveness framework analysis was used to estimate any potential cost benefit of improving adherence. Results Two hundred and eight patients were recruited (102 intervention, 106 control). No significant difference in mean adherence over the monitoring period was identified with 77.2% (CI, 73.0, 81.4) for the control group and 74.8% (CI, 69.7, 79.9) for the intervention group (p = 0.47). Similarly, there was no significant difference in percentage intraocular pressure reduction; 27.6% (CI, 23.5, 31.7) for the control group and 25.3% (CI, 21.06, 29.54) for the intervention group (p = 0.45). Participants in the intervention group were more satisfied with information about glaucoma medication with a mean score of 14.47/17 (CI, 13.85, 15.0) compared with control group which was 8.51 (CI, 7.72, 9.30). The mean intervention cost per patient was GB£10.35 (<US$16) and not cost-effective. Conclusions Adherence with travoprost was high and not further increased by the intervention. Nevertheless, the study demonstrated that provision of information, tailored to the individual, was inexpensive and able to achieve high patient satisfaction with respect to information about glaucoma medication. Measurement of adherence remains problematic since awareness of study participation may cause a change in participant behaviour
Modelling survival : exposure pattern, species sensitivity and uncertainty
The General Unified Threshold model for Survival (GUTS) integrates previously published toxicokinetic-toxicodynamic models and estimates survival with explicitly defined assumptions. Importantly, GUTS accounts for time-variable exposure to the stressor. We performed three studies to test the ability of GUTS to predict survival of aquatic organisms across different pesticide exposure patterns, time scales and species. Firstly, using synthetic data, we identified experimental data requirements which allow for the estimation of all parameters of the GUTS proper model. Secondly, we assessed how well GUTS, calibrated with short-term survival data of Gammarus pulex exposed to four pesticides, can forecast effects of longer-term pulsed exposures. Thirdly, we tested the ability of GUTS to estimate 14-day median effect concentrations of malathion for a range of species and use these estimates to build species sensitivity distributions for different exposure patterns. We find that GUTS adequately predicts survival across exposure patterns that vary over time. When toxicity is assessed for time-variable concentrations species may differ in their responses depending on the exposure profile. This can result in different species sensitivity rankings and safe levels. The interplay of exposure pattern and species sensitivity deserves systematic investigation in order to better understand how organisms respond to stress, including humans
Comparative radiological features of disseminated disease due to Mycobacterium tuberculosis vs non-tuberculosis mycobacteria among AIDS patients in Brazil
Background: Disseminated mycobacterial disease is an important cause of morbidity and mortality in patients with HIV-infection. Nonspecific clinical presentation makes the diagnosis difficult and sometimes neglected. Methods: We conducted a retrospective cohort study to compare the presentation of disseminated Mycobacterial tuberculosis (MTB) and non-tuberculous Mycobacterial (NTM) disease in HIV-positive patients from 1996 to 2006 in Brazil. Results: Tuberculosis (TB) was diagnosed in 65 patients (67.7%) and NTM in 31 (32.3%) patients. Patients with NTM had lower CD4 T cells counts (median 13.0 cells/mm3 versus 42.0 cells/mm3, P = 0.002). Patients with tuberculosis had significantly more positive acid-fast smears (48.0% vs 13.6%, P = 0.01). On chest X-ray, miliary infiltrate was only seen in patients with MTB (28.1% vs. 0.0%, P = 0.01). Pleural effusion was more common in patients with MTB (45.6% vs. 13.0%, P = 0.01). Abdominal adenopathy (73.1% vs. 33.3%, P = 0.003) and splenic hypoechoic nodules (38.5% vs. 0.0%, P = 0.002) were more common in patients with TB. Conclusion: Miliary pulmonary pattern on X-ray, pleural effusion, abdominal adenopathy, and splenic hypoechoic nodules were imaging findings associated with the diagnosis of tuberculosis in HIV-infected patients. Recognition of these imaging features will help to distinguish TB from NTM in AIDS patients with fever of unknown origin due to disseminated mycobacterial disease
Laforin, a Dual Specificity Phosphatase Involved in Lafora Disease, Is Present Mainly as Monomeric Form with Full Phosphatase Activity
Lafora Disease (LD) is a fatal neurodegenerative epileptic disorder that presents as a neurological deterioration with the accumulation of insoluble, intracellular, hyperphosphorylated carbohydrates called Lafora bodies (LBs). LD is caused by mutations in either the gene encoding laforin or malin. Laforin contains a dual specificity phosphatase domain and a carbohydrate-binding module, and is a member of the recently described family of glucan phosphatases. In the current study, we investigated the functional and physiological relevance of laforin dimerization. We purified recombinant human laforin and subjected the monomer and dimer fractions to denaturing gel electrophoresis, mass spectrometry, phosphatase assays, protein-protein interaction assays, and glucan binding assays. Our results demonstrate that laforin prevalently exists as a monomer with a small dimer fraction both in vitro and in vivo. Of mechanistic importance, laforin monomer and dimer possess equal phosphatase activity, and they both associate with malin and bind glucans to a similar extent. However, we found differences between the two states' ability to interact simultaneously with malin and carbohydrates. Furthermore, we tested other members of the glucan phosphatase family. Cumulatively, our data suggest that laforin monomer is the dominant form of the protein and that it contains phosphatase activity
Genome-wide association study identifies susceptibility loci for acute myeloid leukemia
Acute myeloid leukemia (AML) is a hematological malignancy with an undefined heritable risk. Here we perform a meta-analysis of three genome-wide association studies, with replication in a fourth study, incorporating a total of 4018 AML cases and 10488 controls. We identify a genome-wide significant risk locus for AML at 11q13.2 (rs4930561; P = 2.15 × 10-8; KMT5B). We also identify a genome-wide significant risk locus for the cytogenetically normal AML sub-group (N = 1287) at 6p21.32 (rs3916765; P = 1.51 × 10-10; HLA). Our results inform on AML etiology and identify putative functional genes operating in histone methylation (KMT5B) and immune function (HLA)
Genome-wide association study identifies susceptibility loci for acute myeloid leukemia
Acute myeloid leukemia (AML) is a hematological malignancy with an undefined heritable risk. Here we perform a meta-analysis of three genome-wide association studies, with replication in a fourth study, incorporating a total of 4018 AML cases and 10488 controls. We identify a genome-wide significant risk locus for AML at 11q13.2 (rs4930561; P = 2.15 × 10^{-8}; KMT5B). We also identify a genome-wide significant risk locus for the cytogenetically normal AML sub-group (N = 1287) at 6p21.32 (rs3916765; P = 1.51 × 10^{−10}; HLA). Our results inform on AML etiology and identify putative functional genes operating in histone methylation (KMT5B) and immune function (HLA)
A conceptual governance framework for climate change adaptation and disaster risk reduction integration
Climate change adaptation (CCA) and disaster risk reduction (DRR) have similar targets and goals in relation to climate change and related risks. The integration of CCA in core DRR operations is crucial to provide simultaneous benefits for social systems coping with challenges posed by climate extremes and climate change. Although state actors are generally responsible for governing a public issue such as CCA and DRR integration, the reform of top-down governing modes in neoliberal societies has enlarged the range of potential actors to include non state actors from economic and social communities. These new intervening actors require in-depth investigation. To achieve this goal, the article investigates the set of actors and their bridging arrangements that create and shape governance in CCA and DRR integration. The article conducts a comprehensive literature review in order to retrieve main actors and arrangements. The article summarizes actors and arrangements into a conceptual governance framework that can be used as a backdrop for future research on the topic. However, this framework has an explorative form, which must be refined according to site- and context-specific variables, norms, or networks. Accordingly, this article promotes an initial application of the framework to different contexts. Scholars may adopt the framework as a roadmap with which to corroborate the existence of a theoretical and empirical body of knowledge on governance of CCA and DRR integration
- …