364 resultados para Reverse Salient
Resumo:
Bananas are one of the world's most important food crops, providing sustenance and income for millions of people in developing countries and supporting large export industries. Viruses are considered major constraints to banana production, germplasm multiplication and exchange, and to genetic improvement of banana through traditional breeding. In Africa, the two most important virus diseases are bunchy top, caused by Banana bunchy top virus (BBTV), and banana streak disease, caused by Banana streak virus (BSV). BBTV is a serious production constraint in a number of countries within/bordering East Africa, such as Burundi, Democratic Republic of Congo, Malawi, Mozambique, Rwanda and Zambia, but is not present in Kenya, Tanzania and Uganda. Additionally, epidemics of banana streak disease are occurring in Kenya and Uganda. The rapidly growing tissue culture (TC) industry within East Africa, aiming to provide planting material to banana farmers, has stimulated discussion about the need for virus indexing to certify planting material as virus-free. Diagnostic methods for BBTV and BSV have been reported and, for BBTV, PCR-based assays are reliable and relatively straightforward. However for BSV, high levels of serological and genetic variability and the presence of endogenous virus sequences within the banana genome complicate diagnosis. Uganda has been shown to contain the greatest diversity in BSV isolates found anywhere in the world. A broad-spectrum diagnostic test for BSV detection, which can discriminate between endogenous and episomal BSV sequences, is a priority. This PhD project aimed to establish diagnostic methods for banana viruses, with a particular focus on the development of novel methods for BSV detection, and to use these diagnostic methods for the detection and characterisation of banana viruses in East Africa. A novel rolling-circle amplification (RCA) method was developed for the detection of BSV. Using samples of Banana streak MY virus (BSMYV) and Banana streak OL virus (BSOLV) from Australia, this method was shown to distinguish between endogenous and episomal BSV sequences in banana plants. The RCA assay was used to screen a collection of 56 banana samples from south-west Uganda for BSV. RCA detected at least five distinct BSV isolates in these samples, including BSOLV and Banana streak GF virus (BSGFV) as well as three BSV isolates (Banana streak Uganda-I, -L and -M virus) for which only partial sequences had been previously reported. These latter three BSV had only been detected using immuno-capture (IC)-PCR and thus were possible endogenous sequences. In addition to its ability to detect BSV, the RCA protocol was also demonstrated to detect other viruses within the family Caulimoviridae, including Sugar cane bacilliform virus, and Cauliflower mosaic virus. Using the novel RCA method, three distinct BSV isolates from both Kenya and Uganda were identified and characterised. The complete genome of these isolates was sequenced and annotated. All six isolates were shown to have a characteristic badnavirus genome organisation with three open reading frames (ORFs) and the large polyprotein encoded by ORF 3 was shown to contain conserved amino acid motifs for movement, aspartic protease, reverse transcriptase and ribonuclease H activities. As well, several sequences important for expression and replication of the virus genome were identified including the conserved tRNAmet primer binding site present in the intergenic region of all badnaviruses. Based on the International Committee on Taxonomy of Viruses (ICTV) guidelines for species demarcation in the genus Badnavirus, these six isolates were proposed as distinct species, and named Banana streak UA virus (BSUAV), Banana streak UI virus (BSUIV), Banana streak UL virus (BSULV), Banana streak UM virus (BSUMV), Banana streak CA virus (BSCAV) and Banana streak IM virus (BSIMV). Using PCR with species-specific primers designed to each isolate, a genotypically diverse collection of 12 virus-free banana cultivars were tested for the presence of endogenous sequences. For five of the BSV no amplification was observed in any cultivar tested, while for BSIMV, four positive samples were identified in cultivars with a B-genome component. During field visits to Kenya, Tanzania and Uganda, 143 samples were collected and assayed for BSV. PCR using nine sets of species-specific primers, and RCA, were compared for BSV detection. For five BSV species with no known endogenous counterpart (namely BSCAV, BSUAV, BSUIV, BSULV and BSUMV), PCR was used to detect 30 infections from the 143 samples. Using RCA, 96.4% of these samples were considered positive, with one additional sample detected using RCA which was not positive using PCR. For these five BSV, PCR and RCA were both useful for identifying infected samples, irrespective of the host cultivar genotype (Musa A- or B-genome components). For four additional BSV with known endogenous counterparts in the M. balbisiana genome (BSOLV, BSGFV, BSMYV and BSIMV), PCR was shown to detect 75 infections from the 143 samples. In 30 samples from cultivars with an A-only genome component there was 96.3% agreement between PCR positive samples and detection using RCA, again demonstrating either PCR or RCA are suitable methods for detection. However, in 45 samples from cultivars with some B-genome component, the level of agreement between PCR positive samples and RCA positive samples was 70.5%. This suggests that, in cultivars with some B-genome component, many infections were detected using PCR which were the result of amplification of endogenous sequences. In these latter cases, RCA or another method which discriminates between endogenous and episomal sequences, such as immuno-capture PCR, is needed to diagnose episomal BSV infection. Field visits were made to Malawi and Rwanda to collect local isolates of BBTV for validation of a PCR-based diagnostic assay. The presence of BBTV in samples of bananas with bunchy top disease was confirmed in 28 out of 39 samples from Malawi and all nine samples collected in Rwanda, using PCR and RCA. For three isolates, one from Malawi and two from Rwanda, the complete nucleotide sequences were determined and shown to have a similar genome organisation to previously published BBTV isolates. The two isolates from Rwanda had at least 98.1% nucleotide sequence identity between each of the six DNA components, while the similarity between isolates from Rwanda and Malawi was between 96.2% and 99.4% depending on the DNA component. At the amino acid level, similarities in the putative proteins encoded by DNA-R, -S, -M, - C and -N were found to range between 98.8% to 100%. In a phylogenetic analysis, the three East African isolates clustered together within the South Pacific subgroup of BBTV isolates. Nucleotide sequence comparison to isolates of BBTV from outside Africa identified India as the possible origin of East African isolates of BBTV.
Resumo:
Enterprise Systems (ES) have emerged as possibly the most important and challenging development in the corporate use of information technology in the last decade. Organizations have invested heavily in these large, integrated application software suites expecting improvments in; business processes, management of expenditure, customer service, and more generally, competitiveness, improved access to better information/knowledge (i.e., business intelligence and analytics). Forrester survey data consistently shows that investment in ES and enterprise applications in general remains the top IT spending priority, with the ES market estimated at $38 billion and predicted to grow at a steady rate of 6.9%, reaching $50 billion by 2012 (Wang & Hamerman, 2008). Yet, organizations have failed to realize all the anticipated benefits. One of the key reasons is the inability of employees to properly utilize the capabilities of the enterprise systems to complete the work and extract information critical to decision making. In response, universities (tertiary institutes) have developed academic programs aimed at addressing the skill gaps. In parallel with the proliferation of ES, there has been growing recognition of the importance of Teaching Enterprise Systems at tertiary education institutes. Many academic papers have discused the important role of Enterprise System curricula at tertiary education institutes (Ask, 2008; Hawking, 2004; Stewart, 2001), where the teaching philosophises, teaching approaches and challenges in Enterprise Systems education were discussed. Following the global trends, tertiary institutes in the Pacific-Asian region commenced introducing Enterprise System curricula in late 1990s with a range of subjects (a subject represents a single unit, rather than a collection of units; which we refer to as a course) in faculties / schools / departments of Information Technology, Business and in some cases in Engineering. Many tertiary educations commenced their initial subject offers around four salient concepts of Enterprise Systems: (1) Enterprise Systems implementations, (2) Introductions to core modules of Enterprise Systems, (3) Application customization using a programming language (e.g. ABAP) and (4) Systems Administration. While universities have come a long way in developing curricula in the enterprise system area, many obstacles remain: high cost of technology, qualified faculty to teach, lack of teaching materials, etc.
Resumo:
Objective: We hypothesize that chondrocytes from distinct zones of articular cartilage respond differently to compressive loading, and that zonal chondrocytes from osteoarthritis (OA) patients can benefit from optimized compressive stimulation. Therefore, we aimed to determine the transcriptional response of superficial (S) and middle/deep (MD) zone chondrocytes to varying dynamic compressive strain and loading duration. To confirm effects of compressive stimulation on overall matrix production, we subjected zonal chondrocytes to compression for 2 weeks. Design: Human S and MD chondrocytes from osteoarthritic joints were encapsulated in 2% alginate, pre-cultured, and subjected to compression with varying dynamic strain (5, 15, 50% at 1 Hz) and loading duration (1, 3, 12 h). Temporal changes in cartilage-specific, zonal, and dedifferentiation genes following compression were evaluated using quantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR). The benefits of long-term compression (50% strain, 3 h/day, for 2 weeks) were assessed by measuring construct glycosaminoglycan (GAG) content and compressive moduli, as well as immunostaining. Results: Compressive stimulation significantly induced aggrecan (ACAN), COL2A1, COL1A1, proteoglycan 4 (PRG4), and COL10A1 gene expression after 2 h of unloading, in a zone-dependent manner (P < 0.05). ACAN and PRG4 mRNA levels depended on strain and load duration, with 50% and 3 h loading resulting in highest levels (P < 0.05). Long-term compression increased collagen type II and ACAN immunostaining and total GAG (P < 0.05), but only S constructs showed more PRG4 stain, retained more GAG (P < 0.01), and developed higher compressive moduli than non-loaded controls. Conclusions: The biosynthetic activity of zonal chondrocytes from osteoarthritis joints can be enhanced with selected compression regimes, indicating the potential for cartilage tissue engineering applications. © 2012 Osteoarthritis Research Society International.
Resumo:
In the last two decades there has been a plethora of research on a range of subjects collectively and rhetorically known as ‘work-life balance’. The bulk of this research, which spans disciplines including feminist sociology, industrial relations and management, has focused on the significant concerns of employed women and/or dual career couples. Less attention has been devoted to scholarship which explicitly examines men and masculinities in this context. Meanwhile, public and organizational discourse is largely espoused in gender neutral terms, often neglecting salient gendered issues which differentially impact the ability of women and men to successfully integrate their work and non-work lives. This edited book brings together empirical studies of the work-life nexus with a specific focus on men’s working time arrangements, how men navigate and traverse paid work and family commitments, and the impact of public and organizational policies on men’s participation in work, leisure, and other life domains. The book is innovative in that it presents both macro (institutional, how policy affects practice) and micro (individual, from men’s own perspectives) level studies, allowing for a rich and contrasting exploration of how men’s participation in paid work and other domains is divided, conflicted, or integrated. The essays in this volume address issues of fundamental social, labor market, and economic change which have occurred over the last 20 years and which have profoundly affected the way work, care, leisure and community have evolved in different contexts. Taking an international focus, Men, Wage Work and Family contrasts various public and organizational policies and how these policies impact men’s opportunities and participation in paid work and non-work domains in industrialised countries in Europe, North America, and Australia.
Resumo:
In the last two decades there has been a plethora of research on a range of subjects collectively and rhetorically known as ‘work-life balance’. The bulk of this research, which spans disciplines including feminist sociology, industrial relations and management, has focused on the significant concerns of employed women and/or dual career couples. Less attention has been devoted to scholarship which explicitly examines men and masculinities in this context. Meanwhile, public and organizational discourse is largely espoused in gender neutral terms, often neglecting salient gendered issues which differentially impact the ability of women and men to successfully integrate their work and non-work lives. This edited book brings together empirical studies of the work-life nexus with a specific focus on men’s working time arrangements, how men navigate and traverse paid work and family commitments, and the impact of public and organizational policies on men’s participation in work, leisure, and other life domains. The book is innovative in that it presents both macro (institutional, how policy affects practice) and micro (individual, from men’s own perspectives) level studies, allowing for a rich and contrasting exploration of how men’s participation in paid work and other domains is divided, conflicted, or integrated. The essays in this volume address issues of fundamental social, labor market, and economic change which have occurred over the last 20 years and which have profoundly affected the way work, care, leisure and community have evolved in different contexts. Taking an international focus, Men, Wage Work and Family contrasts various public and organizational policies and how these policies impact men’s opportunities and participation in paid work and non-work domains in industrialised countries in Europe, North America, and Australia.
Resumo:
This paper describes part of an action research study that was designed to explore the outcomes of an ongoing program in which the participants, a group of domestic and international pre-service teachers and lecturers, worked together in reflective writing workshops. While the primary long-term goal of the program was to develop the intercultural competence and understanding of all of the participants through social activities, the development of social relationships was initiated and supported by involving the participants in weekly writing workshops that focused on shared salient skills of critical reflective thinking and writing. The focus of this paper is upon the outcomes for the international students, a cohort of second year pre-service teachers from Malaysia. Findings indicated that the program was successful in developing the Malaysian pre-service teachers’ self-confidence in perceiving themselves as writers and future teachers of writing, in shifting their focus from writing product to writing process and content, and in increasing the depth of their critical reflective thinking and writing
Resumo:
The overall objective of this thesis is to explore how and why the content of individuals' psychological contracts changes over time. The contract is generally understood as "individual beliefs, shaped by the organisation, regarding the terms of an exchange agreement between individuals and their organisation" (Rousseau, 1995, p. 9). With an overall study sampling frame of 320 graduate organisational newcomers, a mixed method longitudinal research design comprised of three sequential, inter-related studies is employed in order to capture the change process. From the 15 semi-structured interviews conducted in Study 1, the key findings included identifying a relatively high degree of mutuality between employees' and their managers' reciprocal contract beliefs around the time of organisational entry. Also, at this time, individuals had developed specific components of their contract content through a mix of social network information (regarding broader employment expectations) and perceptions of various elements of their particular organisation's reputation (for more firm-specific expectations). Study 2 utilised a four-wave survey approach (available to the full sampling frame) over the 14 months following organisational entry to explore the 'shape' of individuals' contract change trajectories and the role of four theorised change predictors in driving these trajectories. The predictors represented an organisational-level informational cue (perceptions of corporate reputation), a dyadic-level informational cue (perceptions of manager-employee relationship quality) and two individual difference variables (affect and hardiness). Through the use of individual growth modelling, the findings showed differences in the general change patterns across contract content components of perceived employer (exhibiting generally quadratic change patterns) and employee (exhibiting generally no-change patterns) obligations. Further, individuals differentially used the predictor variables to construct beliefs about specific contract content. While both organisational- and dyadic-level cues were focused upon to construct employer obligation beliefs, organisational-level cues and individual difference variables were focused upon to construct employee obligation beliefs. Through undertaking 26 semi-structured interviews, Study 3 focused upon gaining a richer understanding of why participants' contracts changed, or otherwise, over the study period, with a particular focus upon the roles of breach and violation. Breach refers to an employee's perception that an employer obligation has not been met and violation refers to the negative and affective employee reactions which may ensue following a breach. The main contribution of these findings was identifying that subsequent to a breach or violation event a range of 'remediation effects' could be activated by employees which, depending upon their effectiveness, served to instigate either breach or contract repair or both. These effects mostly instigated broader contract repair and were generally cognitive strategies enacted by an individual to re-evaluate the breach situation and re-focus upon other positive aspects of the employment relationship. As such, the findings offered new evidence for a clear distinction between remedial effects which serve to only repair the breach (and thus the contract) and effects which only repair the contract more broadly; however, when effective, both resulted in individuals again viewing their employment relationships positively. Overall, in response to the overarching research question of this thesis, how and why individuals' psychological contract beliefs change, individuals do indeed draw upon various information sources, particularly at the organisational-level, as cues or guides in shaping their contract content. Further, the 'shapes' of the changes in beliefs about employer and employee obligations generally follow different, and not necessarily linear, trajectories over time. Finally, both breach and violation and also remedial actions, which address these occurrences either by remedying the breach itself (and thus the contract) or the contract only, play central roles in guiding individuals' contract changes to greater or lesser degrees. The findings from the thesis provide both academics and practitioners with greater insights into how employees construct their contract beliefs over time, the salient informational cues used to do this and how the effects of breach and violation can be mitigated through creating an environment which facilitates the use of effective remediation strategies.
Resumo:
Current English-as-a-second and foreign-language (ESL/EFL) research has encouraged to treat each communicative macroskill separately due to space constraint, but the interrelationship among these skills (listening, speaking, reading, and writing) is not paid due attention. This study attempts to examine first the existing relationship among the four dominant skills, second the potential impact of reading background on the overall language proficiency, and finally the relationship between listening and overall language proficiency as listening is considered an overlooked/passive skill in the pedagogy of the second/foreign language classroom. However, the literature in language learning has revealed that listening skill has salient importance in both first and second language learning. The purpose of this study is to investigate the role of each of four skills in EFL learning and their existing interrelationships in an EFL setting. The outcome of 701 Iranian applicants undertaking International English Language Testing System (IELTS) in Tehran demonstrates that all communicative macroskills have varied correlations from moderate (reading and writing) to high (listening and reading). The findings also show that the applicants’ reading history assisted them in better performing at high stakes tests, and what is more, listening skill was strongly correlated with the overall language proficiency.
Resumo:
Ghassan Hage asserts the “core element of Australia’s colonial paranoia is a fear of loss of Europeanness or Whiteness and the lifestyle and privileges that are seen to emanate directly from them. This is a combination of the fragility of White European colonial identity in general and the specificity of the Australian situation” (419). This ‘White paranoia’ can be traced through a range of popular cultural formations, including contemporary Australian children’s literature. The Children’s Book Council of Australia (CBCA) awards an annual prize for “outstanding books which have the prime intention of documenting factual material with consideration given to imaginative presentation, interpretation and variation of style” (“Awards”) published in the preceding year. Although not often included in critical debates, non-fictional texts overtly seek to shape young readers’ understandings of their national context and their own location as national subjects. Thus, the books named as winners and honours of this prize from 2001-2010 provide a snapshot of which facts and whose fictions are salient in shaping the Australian nation in the twenty-first century. Using Hage’s concept of Australian colonial paranoia, this paper considers the relationship between ‘factual material’ and ‘imaginative presentation’ in the ongoing revision and renewal of national myths in award-winning Australian non-fiction for children.
Resumo:
The recent expansion of prediction markets provides a great opportunity to test the market efficiency hypothesis and the calibration of trader judgements. Using a large database of observed prices, this article studies the calibration of prediction markets prices on sporting events using both nonparametric and parametric methods. While only minor bias can be observed during most of the lifetime of the contracts, the calibration of prices deteriorates very significantly in the last moments of the contracts’ lives. Traders tend to overestimate the probability of the losing team to reverse the situation in the last minutes of the game.
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Background: Tenofovir has been associated with renal phosphate wasting, reduced bone mineral density, and higher parathyroid hormone levels. The aim of this study was to carry out a detailed comparison of the effects of tenofovir versus non-tenofovir use on calcium, phosphate and, vitamin D, parathyroid hormone (PTH), and bone mineral density. Methods: A cohort study of 56 HIV-1 infected adults at a single centre in the UK on stable antiretroviral regimes comparing biochemical and bone mineral density parameters between patients receiving either tenofovir or another nucleoside reverse transcriptase inhibitor. Principal Findings: In the unadjusted analysis, there was no significant difference between the two groups in PTH levels (tenofovir mean 5.9 pmol/L, 95% confidence intervals 5.0 to 6.8, versus non-tenofovir; 5.9, 4.9 to 6.9; p = 0.98). Patients on tenofovir had significantly reduced urinary calcium excretion (median 3.01 mmol/24 hours) compared to non-tenofovir users (4.56; p,0.0001). Stratification of the analysis by age and ethnicity revealed that non-white men but not women, on tenofovir had higher PTH levels than non-white men not on tenofovir (mean difference 3.1 pmol/L, 95% CI 5.3 to 0.9; p = 0.007). Those patients with optimal 25-hydroxyvitamin D (.75 nmol/L) on tenofovir had higher 1,25-dihydroxyvitamin D [1,25(OH)2D] (median 48 pg/mL versus 31; p = 0.012), fractional excretion of phosphate (median 26.1%, versus 14.6;p = 0.025) and lower serum phosphate (median 0.79 mmol/L versus 1.02; p = 0.040) than those not taking tenofovir. Conclusions: The effects of tenofovir on PTH levels were modified by sex and ethnicity in this cohort. Vitamin D status also modified the effects of tenofovir on serum concentrations of 1,25(OH)2D and phosphate.
Resumo:
This elicitation study was designed to explore salient behavioural, normative, and control beliefs in accordance with the Theory Planned Behaviour (TPB) and in relation to drivers’ speeding behaviour in school zones. The study also explored mindfulness and habit as additional constructs in the TPB framework. The aim of this study was to identify those beliefs which influenced drivers’ speeding behaviour in school zones and thus gain greater insight into the motivating factors underpinning the behaviour which may inform interventions to reduce this behaviour. Seventeen Australian drivers participated in one of a series of focus group discussions. Overall, conceptual content analysis revealed some similar issues across the groups. In particular, highlighting the influence of behavioural and normative beliefs, there was much agreement that there were no real advantages to speeding in school zones with the behaviour considered dangerous and unacceptable and likely to also be regarded as such by important others. In addition, given the public concern about safety of school children, acknowledgment of such concern represented an important factor discouraging one’s likelihood of engaging in speeding in school zones (i.e., complying with the school zone speed limit). However, despite normative support not to speed, and the need to ensure children’s safety as an important factor discouraging speeding, the study also found that there was a tendency for drivers to report unintentionally speeding in a school zone. Instances of unintentional speeding were reported as occurring due to several reasons including a driver’s current affective state (e.g., more likely to speed in a school zone if they were in a bad mood), the extent to which they were familiar with the environment (i.e., more likely to drive mindlessly – on ‘autopilot’ - in more familiar contexts) and when feeling fatigued. The theoretical implications of including mindfulness and habit with TPB constructs and the practical implications in terms of suggested interventions are discussed.
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Home purchase and ownership is seen by the majority of Australians as the basis for a sound investment strategy and to seciure their long term retirement goals. Although home ownership rates in Australia are in excess of 65% of the population, there have been doubts raised as to the effectiveness of purchasing a house as the main source of retirement income. The main issue with this approach is that the house has to be sold to gain access to these funds or the owners have to take out a reverse mortgage to access the capital tied up in their home, which can be more expensive than selling. This paper will carryout a detailed analysis of a number of investment options to determine the effectiveness of home purchase as a long term investment vehicle. This study has found that the long term investment in equities or managed superannuation funds can provide a greater retirement income than the purchase of a residential property for owner occupation
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Siamese mud carp (Henichorynchus siamensis) is a freshwater teleost of high economic importance in the Mekong River Basin. However, genetic data relevant for delineating wild stocks for management purposes currently are limited for this species. Here, we used 454 pyrosequencing to generate a partial genome survey sequence (GSS) dataset to develop simple sequence repeat (SSR) markers from H. siamensis genomic DNA. Data generated included a total of 65,954 sequence reads with average length of 264 nucleotides, of which 2.79% contain SSR motifs. Based on GSS-BLASTx results, 10.5% of contigs and 8.1% singletons possessed significant similarity (E value < 10–5) with the majority matching well to reported fish sequences. KEGG analysis identified several metabolic pathways that provide insights into specific potential roles and functions of sequences involved in molecular processes in H. siamensis. Top protein domains detected included reverse transcriptase and the top putative functional transcript identified was an ORF2-encoded protein. One thousand eight hundred and thirty seven sequences containing SSR motifs were identified, of which 422 qualified for primer design and eight polymorphic loci have been tested with average observed and expected heterozygosity estimated at 0.75 and 0.83, respectively. Regardless of their relative levels of polymorphism and heterozygosity, microsatellite loci developed here are suitable for further population genetic studies in H. siamensis and may also be applicable to other related taxa.
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Background: Understanding frequency of foot problems can assist health care planners with resource deployment to new and emerging services such as paediatric podiatry and focus future research on the most salient foot conditions. Methods: A review of 2187 patient consultations during a three month period was conducted. Patient medical and podiatric history was coded using industry standards. All patients were recruited for convenience from a metropolitan university podiatry clinic. Results: 392 new patients were identified with mean age 40.6 years old (range 1–95), with 65% being female. Arthritic diseases, asthma, hypertension and allergies were the most common medical conditions reported. The frequency of new consultations in younger people (n = 102; 27%) exceeded those of the elderly (n = 75; 20%). Conversely, the elderly were nearly three times more prevalent in this cohort (n = 910; 43%) compared to younger people (n = 332; 16%). Conclusion: This study illustrates the diverse nature of pathology seen by podiatrists. Knowledge that skin lesions are highly prevalent is of relevance to health departments, given the aging nature of most populations. Moreover there appears to be a growing trend in the number of young people who present for care, however government funded access to these services are limited.