Confronting expectation in grade 4: Tossing two coins

This study focuses on the experiences of 91 Grade 4 students who had been introduced to expectation and variation through trials of tossing a single coin many times. They were then given two coins to toss simultaneously and asked to state their expectation of the chances for the possible outcomes, in a similar manner expressed for a single coin. This paper documents the journey of the students in discovering that generally their initial expectation for two coins was incorrect and that despite variation, a large number of tosses could confirm a new expectation.

Expectation and variation with a virtual die

By the time students reach the middle years they have experienced many chance activities based on dice. Common among these are rolling one die to explore the relationship of frequency and theoretical probability, and rolling two dice and summing the outcomes to consider their probabilities. Although dice may be considered overused by some, the advantage they offer is a familiar context within which to explore much more complex concepts. If the basic chance mechanism of the device is understood, it is possible to enter quickly into an arena of more complex concepts. This is what happened with a two hour activity engaged in by four classes of Grade 6 students in the same school. The activity targeted the concepts of variation and expectation. The teachers held extended discussions with their classes on variation and expectation at the beginning of the activity, with students contributing examples of the two concepts from their own experience. These notions are quite sophisticated for Grade 6, but the underlying concepts describe phenomena that students encounter every day. For example, time varies continuously; sporting results vary from game to game; the maximum temperature varies from day to day. However, there is an expectation about tomorrow’s maximum temperature based on the expert advice from the weather bureau. There may also be an expectation about a sporting result based on the participants’ previous results. It is this juxtaposition that makes life interesting. Variation hence describes the differences we see in phenomena around us. In a scenario displaying variation, expectation describes the effort to characterise or summarise the variation and perhaps make a prediction about the message arising from the scenario. The explicit purpose of the activity described here was to use the familiar scenario of rolling a die to expose these two concepts. Because the students had previously experienced rolling physical dice they knew instinctively about the variation that occurs across many rolls and about the theoretical expectation that each side should “come up” one-sixth of the time. They had observed the instances of the concepts in action, but had not consolidated the underlying terminology to describe it. As the two concepts are so fundamental to understanding statistics, we felt it would be useful to begin building in the familiar environment of rolling a die. Because hand-held dice limit the explorations students can undertake, the classes used the soft-ware TinkerPlots (Konold & Miller, 2011) to simulate rolling a die multiple times.

Ortho-Dihydroxyl-9,10-anthraquinone dyes as visible-light sensitizers that exhibit a high turnover number for hydrogen evolution

Pt/TiO2 sensitized by the cheap and organic ortho-dihydroxyl-9,10-anthraquinone dyes, such as Alizarin and Alizarin Red, achieved a TON of approximately 10 000 (TOF > 250 h−1 for the first ten hours) during >80 hours of visible light irradiation (>420 nm) for photocatalytic hydrogen evolution when triethanolamine was used as the sacrificial donor. The stability and activity enhancements can be attributed to the two highly serviceable redox reactions involving the 9,10-dicarbonyl and ortho-dihydroxyl groups of the anthracene ring, respectively

Consensus statement on the investigation and management of non-radiographic axial spondyloarthritis (nr-axSpA)

Aim Non-radiographic axial spondyloarthritis (nr-axSpA) is axial inflammatory arthritis where plain radiographic damage is not evident. An unknown proportion of these patients will progress to ankylosing spondylitis (AS). The increasing recognition of nr-axSpA has been greatly assisted by the widespread use of magnetic resonance imaging. The aim of this article was to construct a set of consensus statements based on a literature review to guide investigation and promote best management of nr-axSpA. Methods A literature review using Medline was conducted covering the major investigation modalities and treatment options available. A group of rheumatologists and a radiologist with expertise in investigation and management of SpA reviewed the literature and formulated a set of consensus statements. The Grade system encompassing the level of evidence and strength of recommendation was used. The opinion of a patient with nr-axSpA and a nurse experienced in the care of SpA patients was also sought and included. Results The literature review found few studies specifically addressing nr-axSpA, or if these patients were included, their results were often not separately reported. Fourteen consensus statements covering investigation and management of nr-axSpA were formulated. The level of agreement was high and ranged from 8.1 to 9.8. Treatment recommendations vary little with established AS, but this is primarily due to the lack of available evidence on the specific treatment of nr-axSpA. Conclusion The consensus statements aim to improve the diagnosis and management of nr-axSpA. We aim to raise awareness of this condition by the public and doctors and promote appropriate investigation and management.

Elucidating the chromosome 9 association with AS; CARD9 is a candidate gene

Ankylosing spondylitis (AS) is polygenic with contributions from the immunologically relevant genes HLA-B27, ERAP1 and IL23R. A recent genome-wide association screen (GWAS) identified associations (P0.005) with the non-synonymous single-nucleotide polymorphisms (nsSNPs), rs4077515 and rs3812571, in caspase recruitment domain-containing protein 9 (CARD9) and small nuclear RNA-activating complex polypeptide 4 (SNAPC4) on chromosome 9q that had previously been linked to AS. We replicated these associations in a study of 730 AS patients compared with 2879 historic disease controls (rs4077515 P0.0004, odds ratio (OR)1.2, 95% confidence interval (CI)1.1-1.4; rs3812571 P0.0003, OR1.2, 95% CI1.1-1.4). Meta-analysis revealed strong associations of both SNPs with AS, rs4077515 P0.000005, OR1.2, 95% CI1.1-1.3 and rs3812571 P0.000006, OR1.2, 95% CI1.1-1.3. We then typed 1604 AS cases and 1020 controls for 13 tagging SNPs; 6 showed at least nominal association, 5 of which were in CARD9. We imputed genotypes for 13 additional SNPs but none was more strongly associated with AS than the tagging SNPs. Finally, interrogation of an mRNA expression database revealed that the SNPs most strongly associated with AS (or in strong linkage disequilibrium) were those most associated with CARD9 expression. CARD9 is a plausible candidate for AS given its central role in the innate immune response.

Target acquired: Progress and promise of targeted therapeutics in the treatment of prostate cancer

Cancer is fundamentally a genomic disease caused by mutations or rearrangements in the DNA or epigenetic machinery of a patient. An emerging field in cancer treatment targets key aberrations arising from the mutational landscape of an individual patient’s disease rather than employing a cancer-wide cytotoxic therapy approach. In prostate cancer in particular, where there is an observed variation in response to standard treatments between patients with disease of a similar pathological stage and grade, mutationdirected treatment may grow to be a viable tool for clinicians to tailor more effective treatments. This review will describe a number of mutations across multiple forms of cancer that have been successfully antagonised by targeted therapeutics including their identification, the development of targeted compounds to combat them and the development of resistance to these therapies. This review will continue to examine these same mutations in the treatment and management of prostate cancer; the prevalence of targetable mutations in prostate cancer, recent clinical trials of targeted-agents and the potential or limitations for their use.

Heparin versus 0.9% sodium chloride intermittent flushing for the prevention of occlusion in long term central venous catheters in infants and children

Background Guidelines and clinical practice for the prevention of complications associated with central venous catheters (CVC) around the world vary greatly. Most institutions recommend the use of heparin to prevent occlusion, however there is debate regarding the need for heparin and evidence to suggest 0.9% sodium chloride (normal saline) may be as effective. The use of heparin is not without risk, may be unnecessary and is also associated with increased cost. Objectives To assess the clinical effects (benefits and harms) of intermittent flushing of heparin versus normal saline to prevent occlusion in long term central venous catheters in infants and children. Search Methods The Cochrane Vascular Trials Search Co-ordinator searched the Specialised Register (last searched April 2015) and the Cochrane Register of Studies (Issue 3, 2015). We also searched the reference lists of retrieved trials. Selection criteria Randomised controlled trials that compared the efficacy of normal saline with heparin to prevent occlusion of long term CVCs in infants and children aged up to 18 years of age were included. We excluded temporary CVCs and peripherally inserted central catheters (PICC). Data Collection and Analysis Two review authors independently assessed trial inclusion criteria, trial quality and extracted data. Rate ratios were calculated for two outcome measures - occlusion of the CVC and central line-associated blood stream infection. Other outcome measures included duration of catheter placement, inability to withdraw blood from the catheter, use of urokinase or recombinant tissue plasminogen, incidence of removal or re-insertion of the catheter, or both, and other CVC-related complications such as dislocation of CVCs, other CVC site infections and thrombosis. Main Results Three trials with a total of 245 participants were included in this review. The three trials directly compared the use of normal saline and heparin, however, between studies, all used different protocols for the standard and experimental arms with different concentrations of heparin and different frequency of flushes reported. In addition, not all studies reported on all outcomes. The quality of the evidence ranged from low to very low because there was no blinding, heterogeneity and inconsistency between studies was high and the confidence intervals were wide. CVC occlusion was assessed in all three trials (243 participants). We were able to pool the results of two trials for the outcomes of CVC occlusion and CVC-associated blood stream infection. The estimated rate ratio for CVC occlusion per 1000 catheter days between the normal saline and heparin group was 0.75 (95% CI 0.10 to 5.51, two studies, 229 participants, very low quality evidence). The estimated rate ratio for CVC-associated blood stream infection was 1.48 (95% CI 0.24 to 9.37, two studies, 231 participants; low quality evidence). The duration of catheter placement was reported to be similar between the two study arms, in one study (203 participants). Authors' Conclusions The review found that there was not enough evidence to determine the effects of intermittent flushing of heparin versus normal saline to prevent occlusion in long term central venous catheters in infants and children. Ultimately, if this evidence were available, the development of evidenced-based clinical practice guidelines and consistency of practice would be facilitated.

Distribution of ocular biometry in 7- and 14-year-old Chinese children

Purpose: To describe distributions of ocular biometry and their associations with refraction in 7- and 14-year-old children in urban areas of Anyang, central China. Methods: A total of 2271 grade 1 students aged 7.1 ± 0.4 years and 1786 grade 8 students aged 13.7 ± 0.5 years were measured with ocular biometry and cycloplegic refraction. A parental myopia questionnaire was administered to parents. Results: Mean axial length, anterior chamber depth, lens thickness, central corneal thickness, corneal diameter, corneal radius of curvature, axial length/corneal radius of curvature ratio, and spherical equivalent refraction were 22.72 ± 0.76 mm, 2.89 ± 0.24 mm, 3.61 ± 0.19 mm, 540.5 ± 31 μm, 12.06 ± 0.44 mm, 7.80 ± 0.25 mm, 2.91 ± 0.08, and +0.95 ± 1.05 diopters (D), respectively, in 7-year-old children. They were 24.39 ± 1.13 mm, 3.42 ± 0.41 mm, 3.18 ± 0.24 mm, 548.9 ± 33 μm, 12.03 ± 0.43 mm, 7.80 ± 0.26 mm, 3.13 ± 0.14, and −2.06 ± 2.20 D, respectively, in 14-year-old children. Compared with 7-year-old children, the older group had significantly more myopia (−3.0 D), longer axial length (1.7 mm), deeper anterior chamber depth (0.3 mm), thinner lens thickness (−0.2 mm), thicker central corneal thickness (10 μm), and greater axial length/corneal radius of curvature ratio (0.22) (all p < 0.001), as well as smaller corneal diameter (−0.03 mm, p = 0.02) and similar corneal radius of curvature. Sex differences were similar in both age groups, with boys having longer axial length (0.5 mm), deeper anterior chamber depth (0.1 mm), shorter lens thickness (0.03 mm), greater central corneal thickness (5 μm), greater corneal diameter (0.15 mm), and greater corneal radius of curvature (0.14 mm) than girls (all p < 0.01). The most important variables related to spherical equivalent refraction were vitreous length, corneal radius of curvature, and lens thickness. Conclusions: The 14-year-old group had larger parameter dimensions than the 7-year-old group except for corneal radius of curvature (unchanged) and lens thickness and corneal diameter (both smaller). Boys had large parameter dimensions than girls except for lens thickness (smaller). Axial length, corneal radius of curvature, and lens thickness were the most important determinants of refraction.

Cost and outcomes of assessing patients with chest pain in an Australian emergency department

Objectives: We sought to characterise the demographics, length of admission, final diagnoses, long-term outcome and costs associated with the population who presented to an Australian emergency department (ED) with symptoms of possible acute coronary syndrome (ACS). Design, setting and participants: Prospectively collected data on ED patients presenting with suspected ACS between November 2008 and February 2011 was used, including data on presentation and at 30 days after presentation. Information on patient disposition, length of stay and costs incurred was extracted from hospital administration records. Main outcome measures: Primary outcomes were mean and median cost and length of hospital stay. Secondary outcomes were diagnosis of ACS, other cardiovascular conditions or non-cardiovascular conditions within 30 days of presentation. Results: An ACS was diagnosed in 103 (11.1%) of the 926 patients recruited. 193 patients (20.8%) were diagnosed with other cardiovascular-related conditions and 622 patients (67.2%) had non-cardiac-related chest pain. ACS events occurred in 0 and 11 (1.9%) of the low-risk and intermediate-risk groups, respectively. Ninety-two (28.0%) of the 329 high-risk patients had an ACS event. Patients with a proven ACS, high-grade atrioventricular block, pulmonary embolism and other respiratory conditions had the longest length of stay. The mean cost was highest in the ACS group ($13 509; 95% CI, $11 794–$15 223) followed by other cardiovascular conditions ($7283; 95% CI, $6152–$8415) and non-cardiovascular conditions ($3331; 95% CI, $2976–$3685). Conclusions: Most ED patients with symptoms of possible ACS do not have a cardiac cause for their presentation. The current guideline-based process of assessment is lengthy, costly and consumes significant resources. Investigation of strategies to shorten this process or reduce the need for objective cardiac testing in patients at intermediate risk according to the National Heart Foundation and Cardiac Society of Australia and New Zealand guideline is required.

Sitting-time and 9-year all-cause mortality in older women

Background Studies of mid-aged adults provide evidence of a relationship between sitting-time and all-cause mortality, but evidence in older adults is limited. The aim is to examine the relationship between total sitting-time and all-cause mortality in older women. Methods The prospective cohort design involved 6656 participants in the Australian Longitudinal Study on Women's Health who were followed for up to 9 years (2002, age 76–81, to 2011, age 85–90). Self-reported total sitting-time was linked to all-cause mortality data from the National Death Index from 2002 to 2011. Cox proportional hazard models were used to examine the relationship between sitting-time and all-cause mortality, with adjustment for potential sociodemographic, behavioural and health confounders. Results There were 2003 (30.1%) deaths during a median follow-up of 6 years. Compared with participants who sat <4 h/day, those who sat 8–11 h/day had a 1.45 times higher risk of death and those who sat ≥11 h/day had a 1.65 times higher risk of death. These risks remained after adding sociodemographic and behavioural covariates, but were attenuated after adjustment for health covariates. A significant interaction (p=0.02) was found between sitting-time and physical activity (PA), with increased mortality risk for prolonged sitting only among participants not meeting PA guidelines (HR for sitting ≥8 h/day: 1.31, 95% CI 1.07 to 1.61); HR for sitting ≥11 h/day: 1.47, CI 1.15 to 1.93). Conclusions Prolonged sitting-time was positively associated with all-cause mortality. Women who reported sitting for more than 8 h/day and did not meet PA guidelines had an increased risk of dying within the next 9 years.

Sleep and self-regulation from birth to 7 years: A retrospective study of children with and without ADHD at 8-9 years

Objective To examine mean level differences, and longitudinal and reciprocal relations among behavioral sleep problems, emotional dysregulation, and attentional regulation across early childhood for children with and without ADHD at 8-9 years. Method This study used data from Growing Up in Australia: The Longitudinal Study of Australian Children (LSAC) – Infant Cohort (n = 4109 analyzed). Children with and without ADHD were identified at age 8-9 years via parent-report of ADHD diagnosis and the 5-item Inattention-Hyperactivity subscale from the Strengths and Difficulties Questionnaire. Maternal report of child sleep problems and self-regulation was collected at 0-1, 2-3, 4-5 and 6-7 years of age. ANOVA was used to compare mean level differences in sleep problems, emotional and attentional regulation by ADHD group. Longitudinal structural equation modeling examined the relations among sleep and self-regulation across time in children with and without ADHD. Results Children with ADHD had persistently elevated levels of sleep problems (from infancy) and emotional and attentional dysregulation compared to controls (from 2-3 years of age). Sleep problems, emotional dysregulation, and attentional regulation were stable over time for both groups. Sleep problems were associated with greater emotional dysregulation two years later from 2-3 years of age for both groups, which in turn was associated with poorer attentional regulation. There was no direct relationship between sleep problems and later attentional regulation. Conclusion Sleep problems in children with and without ADHD are associated with emotional dysregulation, which in turn contributes to poorer attentional functioning. This study highlights the importance of assessing and managing sleep problems in young children.

Crime Justice and Social Democracy: Proceedings of the 3rd International Conference, 9-10 July 2015

We are pleased to present these selected papers from the proceedings of the 3rd Crime, Justice and Social Democracy International Conference, held in July 2015 in Brisbane, Australia. Over 350 delegates attended the conference from 19 countries. The papers collected here reflect the diversity of topics and themes that were explored over three days. The Crime, Justice and Social Democracy International Conference aims to strengthen the intellectual and policy debates concerning links between justice, social democracy, and the reduction of harm and crime, through building more just and inclusive societies and proposing innovative justice responses. In 2015, attendees discussed these issues as they related to ideas of green criminology; indigenous justice; gender, sex and justice; punishment and society; and the emerging notion of ‘Southern criminology’. The need to build global connections to address these challenges is more evident than ever and the conference and these proceedings reflect a growing attention to interdisciplinary, novel, and interconnected responses to contemporary global challenges. Authors in these conference proceedings engaged with issues of online fraud, queer criminology and law, Indigenous incarceration, youth justice, incarceration in Brazil, and policing in Victoria, Australia, among others. The topics explored speak to the themes of the conference and demonstrate the range of challenges facing researchers of crime, harm, social democracy and social justice and the spaces of possibility that such research opens. Our thanks to the conference convenor, Dr Kelly Richards, for organising such a successful conference, and to all those presenters who subsequently submitted such excellent papers for review here. We would also particularly like to thank Jess Rodgers for their tireless editorial assistance, as well as the panel of international scholars who participated in the review process, often within tight timelines.

IWGDF guidance on the prevention of foot ulcers in at-risk patients with diabetes

Recommendations - 1 To identify a person with diabetes at risk for foot ulceration, examine the feet annually to seek evidence for signs or symptoms of peripheral neuropathy and peripheral artery disease. (GRADE strength of recommendation: strong; Quality of evidence: low) - 2 In a person with diabetes who has peripheral neuropathy, screen for a history of foot ulceration or lower-extremity amputation, peripheral artery disease, foot deformity, pre-ulcerative signs on the foot, poor foot hygiene and ill-fitting or inadequate footwear. (Strong; Low) - 3 Treat any pre-ulcerative sign on the foot of a patient with diabetes. This includes removing callus, protecting blisters and draining when necessary, treating ingrown or thickened toe nails, treating haemorrhage when necessary and prescribing antifungal treatment for fungal infections. (Strong; Low) - 4 To protect their feet, instruct an at-risk patient with diabetes not to walk barefoot, in socks only, or in thin-soled standard slippers, whether at home or when outside. (Strong; Low) - 5 Instruct an at-risk patient with diabetes to daily inspect their feet and the inside of their shoes, daily wash their feet (with careful drying particularly between the toes), avoid using chemical agents or plasters to remove callus or corns, use emollients to lubricate dry skin and cut toe nails straight across. (Weak; Low) - 6 Instruct an at-risk patient with diabetes to wear properly fitting footwear to prevent a first foot ulcer, either plantar or non-plantar, or a recurrent non-plantar foot ulcer. When a foot deformity or a pre-ulcerative sign is present, consider prescribing therapeutic shoes, custom-made insoles or toe orthosis. (Strong; Low) - 7 To prevent a recurrent plantar foot ulcer in an at-risk patient with diabetes, prescribe therapeutic footwear that has a demonstrated plantar pressure-relieving effect during walking (i.e. 30% relief compared with plantar pressure in standard of care therapeutic footwear) and encourage the patient to wear this footwear. (Strong; Moderate) - 8 To prevent a first foot ulcer in an at-risk patient with diabetes, provide education aimed at improving foot care knowledge and behaviour, as well as encouraging the patient to adhere to this foot care advice. (Weak; Low) - 9 To prevent a recurrent foot ulcer in an at-risk patient with diabetes, provide integrated foot care, which includes professional foot treatment, adequate footwear and education. This should be repeated or re-evaluated once every 1 to 3 months as necessary. (Strong; Low) - 10 Instruct a high-risk patient with diabetes to monitor foot skin temperature at home to prevent a first or recurrent plantar foot ulcer. This aims at identifying the early signs of inflammation, followed by action taken by the patient and care provider to resolve the cause of inflammation. (Weak; Moderate) - 11 Consider digital flexor tenotomy to prevent a toe ulcer when conservative treatment fails in a high-risk patient with diabetes, hammertoes and either a pre-ulcerative sign or an ulcer on the distal toe. (Weak; Low) - 12 Consider Achilles tendon lengthening, joint arthroplasty, single or pan metatarsal head resection, or osteotomy to prevent a recurrent foot ulcer when conservative treatment fails in a high-risk patient with diabetes and a plantar forefoot ulcer. (Weak; Low) - 13 Do not use a nerve decompression procedure in an effort to prevent a foot ulcer in an at-risk patient with diabetes, in preference to accepted standards of good quality care. (Weak; Low)

Heparin versus 0.9% sodium chloride intermittent flushing for the prevention of occlusion in long term central venous catheters in infants and children: A systematic review

Background Around the world, guidelines and clinical practice for the prevention of complications associated with central venous catheters (CVC) vary greatly. To prevent occlusion, most institutions recommend the use of heparin when the CVC is not in use. However, there is debate regarding the need for heparin and evidence to suggest normal saline may be as effective. The use of heparin is not without risk, may be unnecessary and is also associated with increased costs. Objectives To assess the clinical effects (benefits and harms) of heparin versus normal saline to prevent occlusion in long-term central venous catheters in infants, children and adolescents. Design A Cochrane systematic review of randomised controlled trials was undertaken. - Data sources: The Cochrane Vascular Group Specialised Register (including MEDLINE, CINAHL, EMBASE and AMED) and the Cochrane Register of Studies were searched. Hand searching of relevant journals and reference lists of retrieved articles was also undertaken. - Review Methods: Data were extracted and appraisal undertaken. We included studies that compared the efficacy of normal saline with heparin to prevent occlusion. We excluded temporary CVCs and peripherally inserted central catheters. Rate ratios per 1000 catheter days were calculated for two outcomes, occlusion of the CVC, and CVC-associated blood stream infection. Results Three trials with a total of 245 participants were included in this review. The three trials directly compared the use of normal saline and heparin. However, between studies, all used different protocols with various concentrations of heparin and frequency of flushes. The quality of the evidence ranged from low to very low. The estimated rate ratio for CVC occlusion per 1000 catheter days between the normal saline and heparin group was 0.75 (95% CI 0.10 to 5.51, two studies, 229 participants, very low quality evidence). The estimated rate ratio for CVC-associated blood stream infection was 1.48 (95% CI 0.24 to 9.37, two studies, 231 participants; low quality evidence). Conclusions It remains unclear whether heparin is necessary for CVC maintenance. More well-designed studies are required to understand this relatively simple, but clinically important question. Ultimately, if this evidence were available, the development of evidenced-based clinical practice guidelines and consistency of practice would be facilitated.