The role of unbound oligomers in the nucleation and growth of electrodeposited polypyrrole and method for preparing high strength, high conductivity films

Polypyrrole is a material with immensely useful properties suitable for a wide range of electrochemical applications, but its development has been hindered by cumbersome manufacturing processes. Here we show that a simple modification to the standard electrochemical polymerization method produces polypyrrole films of equivalently high conductivity and superior mechanical properties in one-tenth of the polymerization time. Preparing the film as a series of electrodeposited layers with thorough solvent washing between layering was found to produce excellent quality films even when layer deposition was accelerated by high current. The washing step between the sequentially polymerized layers altered the deposition mechanism, eliminating the typical dendritic growth and generating nonporous deposits. Solvent washing was shown to reduce the concentration of oligomeric species in the near-electrode region and hinder the three-dimensional growth mechanism that occurs by deposition of secondary particles from solution. As artificial muscles, the high density sequentially polymerized films produced the highest mechanical work output yet reported for polypyrrole actuators.

Financial development, shocks, and growth volatility

This paper uses spectral theory to develop the following two testable hypotheses in a unified framework for the predictions of business-cycle and endogenous growth models: (i) financial development affects only business-cycle volatility; and (ii) shocks affect both business-cycle volatility and long-run volatility of GDP growth. In other words, volatility caused by shocks is more persistent than that caused by financial underdevelopment. We decompose the business-cycle and long-run volatility by the spectral method and then test the hypotheses at the cross-country level. Empirical evidence provides support for both hypotheses. Higher private credit, a bank-based measure of financial development, dampens business-cycle volatility but not long-run volatility. Volatility of shocks, as measured by the volatility of changes in the terms of trade, magnifies both business-cycle and long-run volatility. The results are robust to accounting for endogeneity, a market-based measure of financial development, and an alternative method of volatility decomposition.

Development of microfluidic-based analytical methodology for studying the effects of chemotherapy agents on cancer tissue

Whilst a multitude of techniques have been employed to study the biology of tumour tissue and its response to chemotherapeutic reagents, most current methodologies do not capture the sophistication of the in vivo environment. Microfluidics however offers the ability to maintain and interrogate primary tissue samples in an environment with biomimetic flow characteristics. In this study head and neck squamous cell carcinoma (HNSCC) tumour biopsies have been used to investigate the performance of a microfluidic device for generating clinically-useful information. The response of fresh and cryogenically-frozen primary HNSCC or metastatic lymph node samples to chemotherapy drugs (cisplatin, 5-flurouracil or docetaxel), alone and in combination, were monitored for both proliferation (water-soluble tetrazolium salt metabolism) and cell death biomarker release (lactate dehydrogenase, LDH) “off-chip”. The frozen tissue showed no significant difference in terms of either proliferation or LDH release in comparison with the matched fresh samples. Administration of all drugs caused cell death, in a dose-response manner, with the combination showing the greatest amount of cytotoxicity particularly at days 8 and 9; correlating well with published clinical data. The system described here offers an innovative method for studying the tumour microenvironment in vitro and, through incorporation of relevant analytical modules, provides the basis of a pre-clinical device that can be used to define personalised treatment regimens.

Hydrograph separation and development of empirical relationships using single-parameter digital filters

A reliable hydrograph separation method is necessary for surface runoff modeling and hydrological studies. This paper investigates and compares the separation characteristics of two single-parameter digital filters, which are herein referred to as the one-parameter algorithm and the conceptual method. The application of the one-parameter algorithm was found to be restricted to low and medium baseflow separations, with a maximum separation limit of 50% of the total runoff hydrograph. The one-parameter algorithm was also observed to produce unrealistic sharp peaks under the peaks of the measured hydrograph when recession constant is smaller than 0.96. On the other hand, the conceptual method is applicable even for catchments fed largely by groundwater discharge. However, a reliable estimation of recession constant is a prerequisite for applying the conceptual method for large baseflow separations. Based on the hydrograph separation results, useful empirical relationships were developed for a partially urbanized watershed to estimate total runoff and direct runoff from the measured rainfall depth. The relationships between rainfall depth and total runoff depth and rainfall depth and direct runoff depth were found to be well represented by linear equations. The empirical relationships were then applied to estimate the long-term contribution of baseflow and surface runoff to total runoff at the study site. Baseflow was found to contribute about 58–61% of the annual total runoff.

A design-based method for estimating glomerular number in the developing kidney

Low glomerular (nephron) endowment has been associated with an increased risk of cardiovascular and renal disease in adulthood. Nephron endowment in humans is determined by 36 wk of gestation, while in rats and mice nephrogenesis ends several days after birth. Specific genes and environmental perturbations have been shown to regulate nephron endowment. Until now, design-based method for estimating nephron number in developing kidneys was unavailable. This was due in part to the difficulty associated with unambiguously identifying developing glomeruli in histological sections. Here, we describe a method that uses lectin histochemistry to identify developing glomeruli and the physical disector/fractionator principle to provide unbiased estimates of total glomerular number (Nglom). We have characterized Nglom throughout development in kidneys from 76 rats and model this development with a 5-parameter logistic equation to predict Nglom from embryonic day 17.25 to adulthood (r2 = 0.98). This approach represents the first design-based method with which to estimate Nglom in the developing kidney.

Nonlinear dynamic modeling of ionic polymer conductive network composite actuators using rigid finite element method

Ionic polymer conductive network composite (IPCNC) actuators are a class of electroactive polymer composites that exhibit some interesting electromechanical characteristics such as low voltage actuation, large displacements, and benefit from low density and elastic modulus. Thus, these emerging materials have potential applications in biomimetic and biomedical devices. Whereas significant efforts have been directed toward the development of IPMC actuators, the establishment of a proper mathematical model that could effectively predict the actuators' dynamic behavior is still a key challenge. This paper presents development of an effective modeling strategy for dynamic analysis of IPCNC actuators undergoing large bending deformations. The proposed model is composed of two parts, namely electrical and mechanical dynamic models. The electrical model describes the actuator as a resistive-capacitive (RC) transmission line, whereas the mechanical model describes the actuator as a system of rigid links connected by spring-damping elements. The proposed modeling approach is validated by experimental data, and the results are discussed. © 2014 Elsevier B.V. All rights reserved.

Quality of pre-school children's pretend play and subsequent development of semantic organization and narrative re-telling skills

Purpose: This study investigated if the quality of pre-school children's pretend play predicted their semantic organization and narrative re-telling ability when they were in early primary school. It was hypothesized that the elaborateness of a child's play and the child's use of symbols in play were predictors of their semantic organization and narrative re-tell scores of the School Age Oral Language Assessment. Method: Forty-eight children were assessed using the Child-Initiated Pretend Play Assessment when they were aged 4-5 years. Three-to-five years after this assessment their semantic organization and narrative re-telling skills were assessed. Results: Results indicate that the elaborateness of a child's play and their ability to use symbols was predictive of semantic organization skills. Use of symbols in play was the strongest play predictor of narrative re-telling skills. The quality of a pre-school child's ability to elaborate complex sequences in pretend play and use symbols predicted up to 20% of a child's semantic organization and narrative re-telling skills up to 5 years later. Conclusions: The study provides evidence that the quality of pretend play in 4-5 year olds is important for semantic organization and narrative re-telling abilities in the school-aged child.

An optimized mean variance estimation method for uncertainty quantification of wind power forecasts

A statistical optimized technique for rapid development of reliable prediction intervals (PIs) is presented in this study. The mean-variance estimation (MVE) technique is employed here for quantification of uncertainties related with wind power predictions. In this method, two separate neural network models are used for estimation of wind power generation and its variance. A novel PI-based training algorithm is also presented to enhance the performance of the MVE method and improve the quality of PIs. For an in-depth analysis, comprehensive experiments are conducted with seasonal datasets taken from three geographically dispersed wind farms in Australia. Five confidence levels of PIs are between 50% and 90%. Obtained results show while both traditional and optimized PIs are hypothetically valid, the optimized PIs are much more informative than the traditional MVE PIs. The informativeness of these PIs paves the way for their application in trouble-free operation and smooth integration of wind farms into energy systems. © 2014 Elsevier Ltd. All rights reserved.

A contribution to the history of assessment: how a conversation simulator redeems Socratic method

Assessment in education is a recent phenomenon. Although there were counterparts in former epochs, the term assessment only began to be spoken about in education after the Second World War; and, since that time, views, strategies and concerns over assessment have proliferated according to an uncomfortable dynamic. We fear that, increasingly, education is assessment-led rather than learning-led and ‘counter to what is desired’ in an ugly judgemental spirit whose moral underpinnings deserve scrutiny. In this article, we seek to historicise assessment and the anxieties of credentialising students. Through this longer history, we present a philosophy of assessment which underlies the development of a new method in assessment-as-learning. We hope that our development of a conversation simulator helps restore the innocence of education as learning-led, while still delivering on the incumbencies of assessment.

Are vitamins A and D important in the development of food allergy and how are they best measured?

Food allergy has a dramatic impact on a child's (and their family's) quality of life and places a major financial burden on the community. It has been hypothesized that the increase in food allergy may relate to the concordant rise in prevalence of vitamin D insufficiency. More recently a second hypothesis has implicated vitamin A sufficiency in the development of immune tolerance. Together, these hypotheses have prompted investigation into the circulating levels of vitamins A and D in relation to food allergy prevalence. This review aims to examine the relationship between vitamins A and D and food allergy. The first part of this review presents the available epidemiological data which proposes a dramatic increase of food allergy and related anaphylaxis during the last two decades. There is some indirect evidence that variation in food allergy prevalence within countries might be linked with ambient ultra violet radiation exposure and thus potentially with vitamin D levels. Only a few studies to date have directly examined the relationship between measured serum vitamin D levels and either food sensitization or allergy. The significance of vitamin A in food allergy prevalence is only provided through a hypothetical association due to its role in the immune system. The second part of this review discusses the relevant aspects of the analytical methods to assess vitamin A and D levels in children. The primary methods utilized relate to measuring the main circulating forms of vitamins A and D in blood i.e. retinol and 25-hydroxy-vitamin-D3 respectively. Chromatographic separation coupled with mass spectrometric detection is considered the gold standard method for both vitamins. These analytical methods should be fully validated for the use in pediatric populations to ensure they are fit for their clinical purpose.

Development of key messages for adolescents on providing basic mental health first aid to peers: a Delphi consensus study.

AIM: Most young people fail to receive professional treatment for mental disorders; however, they do indicate a preference for sharing problems with peers. This article describes key messages about knowledge and actions to form the basis of a basic mental health first aid (MHFA) course for adolescents to increase recognition of and help seeking for mental health problems by teaching the best knowledge and helping actions a young person can undertake to support a peer with a mental health problem. METHODS: The Delphi method was used to achieve consensus among Australian and Canadian youth mental health experts regarding the importance of statements that describe helping actions a young person can take, and information they should have, to support a friend with a mental health problem. There were two expert panels, one consisting of 36 youth mental health consumer advocates and the other of 97 Youth MHFA instructors. Panellists rated each statement according to how appropriate it would be as a basic mental health first aid message for both a junior adolescent (12-15 years) and a senior adolescent (16-18 years). RESULTS: Out of 98 statements, 78 were endorsed as key basic MHFA messages for junior adolescents and 81 were endorsed for senior adolescents. CONCLUSION: The study has identified key messages for adolescents on how they can help a peer. These messages will form the basis of the curriculum for an MHFA course for adolescents, which will aim to facilitate early recognition of and help seeking for mental health problems in adolescents.

Development of mental health first aid guidelines on how a member of the public can support a person affected by a traumatic event: a Delphi study

BACKGROUND: People who experience traumatic events have an increased risk of developing a range of mental disorders. Appropriate early support from a member of the public, whether a friend, family member, co-worker or volunteer, may help to prevent the onset of a mental disorder or may minimise its severity. However, few people have the knowledge and skills required to assist. Simple guidelines may help members of the public to offer appropriate support when it is needed.

METHODS: Guidelines were developed using the Delphi method to reach consensus in a panel of experts. Experts recruited to the panels included 37 professionals writing, planning or working clinically in the trauma area, and 17 consumer or carer advocates who had been affected by traumatic events. As input for the panels to consider, statements about how to assist someone who has experienced a traumatic event were sourced through a systematic search of both professional and lay literature. These statements were used to develop separate questionnaires about possible ways to assist adults and to assist children, and panel members answered either one questionnaire or both, depending on experience and expertise. The guidelines were written using the items most consistently endorsed by the panels across the three Delphi rounds.

RESULTS: There were 180 items relating to helping adults, of which 65 were accepted, and 155 items relating to helping children, of which 71 were accepted. These statements were used to develop the two sets of guidelines appended to this paper.

CONCLUSIONS: There are a number of actions which may be useful for members of the public when they encounter someone who has experienced a traumatic event, and it is possible that these actions may help prevent the development of some mental health problems in the future. Positive social support, a strong theme in these guidelines, has some evidence for effectiveness in developing mental health problems in people who have experienced traumatic events, but the degree to which it helps has not yet been adequately demonstrated. An evaluation of the effectiveness of these guidelines would be useful in determining their value. These guidelines may be useful to organisations who wish to develop or revise curricula of mental health first aid and trauma intervention training programs and policies. They may also be useful for members of the public who want immediate information about how to assist someone who has experienced a potentially traumatic event.

Development of mental health first aid guidelines for deliberate non-suicidal self-injury: a Delphi study

BACKGROUND: It is estimated that around 4% of the population engages, or has engaged, in deliberate non-suicidal self-injury. In clinical samples, the figures rise as high as 21%. There is also evidence to suggest that these figures may be increasing. A family member or friend may suspect that a person is injuring themselves, but very few people know how to respond if this is the case. Simple first aid guidelines may help members of the public assist people to seek and receive the professional help they require to overcome self-injury.

METHODS: This research was conducted using the Delphi methodology, a method of reaching consensus in a panel of experts. Experts recruited to the panels included 26 professionals, 16 people who had engaged in self-injurious behaviour in the past and 3 carers of people who had engaged in self-injurious behaviour in the past. Statements about providing first aid to a person engaged in self-injurious behaviour were sought from the medical and lay literature, but little was found. Panel members were asked to respond to general questions about first aid for NSSI in a variety of domains and statements were extracted from their responses. The guidelines were written using the items most consistently endorsed by the consumer and professional panels.

RESULTS: Of 79 statements rated by the panels, 18 were accepted. These statements were used to develop the guidelines appended to this paper.

CONCLUSION: There are a number of actions which are considered to be useful for members of the public when they encounter someone who is engaging in deliberate, non-suicidal self-injury. These guidelines will be useful in revising curricula for mental health first aid and NSSI first aid training programs. They can also be used by members of the public who want immediate information about how to assist a person who is engaging in such behaviour.

Development of mental health first aid guidelines for suicidal ideation and behaviour: a Delphi study

BACKGROUND: Suicide is a statistically rare event, but devastating to those left behind and one of the worst possible outcomes associated with mental illness. Although a friend, family member or co-worker may be the first person to notice that a person is highly distressed, few have the knowledge and skills required to assist. Simple guidelines may help such a person to encourage a suicidal individual to seek professional help or decide against suicide.

METHODS: This research was conducted using the Delphi methodology, a method of reaching consensus in a panel of experts. Experts recruited to the panels included 22 professionals, 10 people who had been suicidal in the past and 6 carers of people who had been suicidal in the past. Statements about how to assist someone who is thinking about suicide were sourced through a systematic search of both professional and lay literature. The guidelines were written using the items most consistently endorsed by all three panels.

RESULTS: Of 114 statements presented to the panels, 30 were accepted. These statements were used to develop the guidelines appended to this paper.

CONCLUSION: There are a number of actions which are considered to be useful for members of the public when they encounter someone who is experiencing suicidal thoughts or engaging in suicidal behaviour. These guidelines will be useful in revision of curricula of mental health first aid and suicide intervention training programs. They can also be used by members of the public who want immediate information about how to assist a suicidal person.