A brief review of exercise, bipolar disorder, and mechanistic pathways.

Despite evidence that exercise has been found to be effective in the treatment of depression, it is unclear whether these data can be extrapolated to bipolar disorder. Available evidence for bipolar disorder is scant, with no existing randomized controlled trials having tested the impact of exercise on depressive, manic or hypomanic symptomatology. Although exercise is often recommended in bipolar disorder, this is based on extrapolation from the unipolar literature, theory and clinical expertise and not empirical evidence. In addition, there are currently no available empirical data on program variables, with practical implications on frequency, intensity and type of exercise derived from unipolar depression studies. The aim of the current paper is to explore the relationship between exercise and bipolar disorder and potential mechanistic pathways. Given the high rate of medical co-morbidities experienced by people with bipolar disorder, it is possible that exercise is a potentially useful and important intervention with regard to general health benefits; however, further research is required to elucidate the impact of exercise on mood symptomology.

Contributory factors to patient safety incidents in primary care: protocol for a systematic review

BACKGROUND: Organisations need to systematically identify contributory factors (or causes) which impact on patient safety in order to effectively learn from error. Investigations of error have tended to focus on taking a reactive approach to learning from error, mainly relying on incident-reporting systems. Existing frameworks which aim to identify latent causes of error rely almost exclusively on evidence from non-healthcare settings. In view of this, the Yorkshire Contributory Factors Framework (YCFF) was developed in the hospital setting. Eighty-five percent of healthcare contacts occur in primary care. As a result, this review will build on the work that produced the YCFF, by examining the empirical evidence that relates to the contributory factors of error within a primary care setting. METHODS/DESIGN: Four electronic bibliographic databases will be searched: MEDLINE, Embase, PsycInfo and CINAHL. The database search will be supplemented by additional search methodologies including citation searching and snowballing strategies which include reviewing reference lists and reviewing relevant journal table of contents, that is, BMJ Quality and Safety. Our search strategy will include search combinations of three key blocks of terms. Studies will not be excluded based on design. Included studies will be empirical studies conducted in a primary care setting. They will include some description of the factors that contribute to patient safety. One reviewer (SG) will screen all the titles and abstracts, whilst a second reviewer will screen 50% of the abstracts. Two reviewers (SG and AH) will perform study selection, quality assessment and data extraction using standard forms. Disagreements will be resolved through discussion or third party adjudication. Data to be collected include study characteristics (year, objective, research method, setting, country), participant characteristics (number, age, gender, diagnoses), patient safety incident type and characteristics, practice characteristics and study outcomes. DISCUSSION: The review will summarise the literature relating to contributory factors to patient safety incidents in primary care. The findings from this review will provide an evidence-based contributory factors framework for use in the primary care setting. It will increase understanding of factors that contribute to patient safety incidents and ultimately improve quality of health care.

Changing from primary to secondary school highlights opportunities for school environment interventions aiming to increase physical activity and reduce sedentary behaviour: a longitudinal cohort study.

BACKGROUND: There is little empirical evidence of the impact of transition from primary to secondary school on obesity-related risk behaviour. The purpose of this study was to examine the effect of a change of school system on physical activity (PA) and sedentary behaviour in pre-early adolescents. METHODS: Fifteen schools in Victoria, Australia were recruited at random from the bottom two strata of a five level socio-economic scale. In nine schools, students in year 6 primary school transitioned to a different school for year 7 secondary school, while in six schools (combined primary-secondary), students remained in the same school environment from year 6 to year 7. Time 1 (T1) measures were collected from students (N=245) in year 6 (age 11-13). Time 2 (T2) data were collected from 243 (99%) of the original student cohort when in year 7. PA and sedentary behaviour data were collected objectively (via ActiGraph accelerometer) and subjectively (via child self-report recall questionnaire). School environment data were collected via school staff survey. Change of behaviour analyses were conducted longitudinally i) for all students and ii) by change/no change of school. Mixed model regression analysis tested for behavioural interaction effects of changing/not changing school. RESULTS: Sixty-three percent (N=152) changed schools from T1 to T2. Across all students we observed declines in average daily moderate to vigorous physical activity (MVPA) (-4 min) and light PA (-23 min), and increases in average daily sedentary behaviour (16 min), weekday leisure screen time (17 min) and weekday homework screen time (25 min), all P<0.05. Compared to students who remained in the same school environment, students who changed school reported a greater reduction in PA intensity at recess and lunch, less likelihood to cycle to/from school, greater increase in weekday (41 mins) and weekend (45 mins) leisure screen time (P<0.05) and greater encouragement to participate in sport. School staff surveys identified that sport participation encouragement was greater in primary and combined primary-secondary than secondary schools (P<0.05). CONCLUSION: Transitioning from primary to secondary school negatively impacts on children's PA and sedentary behaviour, and has further compounding effects on behaviour type by changing school environments.

Corrigendum to “Least squares learning and the US treasury bill rate” [Econ. Syst. 38 (2014) 194–204]

Understanding how agents formulate their expectations about Fed behavior is important for market participants because they can potentially use this information to make more accurate estimates of stock and bond prices. Although it is commonly assumed that agents learn over time, there is scant empirical evidence in support of this assumption. Thus, in this paper we test if the forecast of the three month T-bill rate in the Survey of Professional Forecasters (SPF) is consistent with least squares learning when there are discrete shifts in monetary policy. We first derive the mean, variance and autocovariances of the forecast errors from a recursive least squares learning algorithm when there are breaks in the structure of the model. We then apply the Bai and Perron (1998) test for structural change to a forecasting model for the three month T-bill rate in order to identify changes in monetary policy. Having identified the policy regimes, we then estimate the implied biases in the interest rate forecasts within each regime. We find that when the forecast errors from the SPF are corrected for the biases due to shifts in policy, the forecasts are consistent with least squares learning.

Mortgage-Backed Securities (MBS): Is It a Curse or a Blessing for the Australian Home Loan Market? A Natural Experiment

The Australian home loan market has seen a significant and persistent boom over more than two decades. Theextant literature exploring the underlying factors explaining this boom has predominantly looked at thedemand side rather than the supply side. In this paper, we look at a major supply-side issue, the introductionof mortgage-backed securities and its likely impact on the home loan market. In doing so, we have developeda mathematical model that theorises this likely relationship. Our mathematical model predicts possibleexistence of an unstable equilibrium in the home loan market in the presence of mortgage-backed securities.We have subsequently backed up our theoretical exercise with sound empirical evidence acquired andanalysed as a natural experiment in the Australian scenario using quarterly market data on home loans andmortgage-backed securities data for a 36-year period from 1976 to 2012. Using unknown structural breaktests, we have identified significant breaks around late 1992 to mid-1995, clearly indicating that there weresignificant changes in the housing market due to the introduction of mortgage-backed securities in early1993. We have also performed a stability test confirming that under certain conditions this market canbecome unstable.

Developmental improvements in reaching correction efficiency are associated with an increased ability to represent action mentally

We investigated the purported association between developmental changes in the efficiency of online reaching corrections and improved action representation. Younger children (6-7years), older children (8-12years), adolescents (13-17years), and young adults (18-24years) completed a double-step reaching paradigm and a motor imagery task. Results showed similar nonlinear performance improvements across both tasks, typified by substantial changes in efficiency after 6 or 7years followed by incremental improvements. Regression showed that imagery ability significantly predicted reaching efficiency and that this association stayed constant across age. Findings provide the first empirical evidence that more efficient online control through development is predicted, partly, by improved action representation.

Skipping swans: fuelling rates and wind conditions determine differential use of migratory stopover sites of Bewick's Swans Cygnus bewickii

Some migratory birds refuel at stopover sites that they by-pass on the return trip. In theory, this skipping behaviour is only expected in time-selected migrants when the overflown site is of a lower quality than the departure site. We provide empirical evidence that quality differences in stopover sites are the cause for skipping in Bewick's Swans Cygnus bewickii tracked by satellite telemetry. Two and five complete tracks were recorded in spring and autunm, respectively, showing that the White Sea was visited for c. 2 weeks in spring, but by-passed (or visited for a few days at the most) in autumn. Skipping of the White Sea in autumn was predicted by a dynamic programming model which was based on calculated gain rates during stopover in the Pechora Delta and the White Sea. This prediction was not sensitive to plausible variations in gain rates. Relative to the Pechora Delta the White Sea is a poor site because a large tidal amplitude precludes foraging on the beds of the submerged macrophyte Fennel Pondweed Potamogeton pectinatus during high tide. The dynamic programming model predicted a fast autunm migration. However, the phenology of autunm arrival dates of Bewick's Swans on the wintering grounds revealed that only in three out of ten years a significant number of birds was able to reach the wintering grounds without refuelling. In the other years, unfavourable wind conditions along the Russian/Baltic part of the route prevented such non-stop migration.

Loss of 'blue carbon' from coastal salt marshes following habitat disturbance

Increased recognition of the global importance of salt marshes as 'blue carbon' (C) sinks has led to concern that salt marshes could release large amounts of stored C into the atmosphere (as CO2) if they continue undergoing disturbance, thereby accelerating climate change. Empirical evidence of C release following salt marsh habitat loss due to disturbance is rare, yet such information is essential for inclusion of salt marshes in greenhouse gas emission reduction and offset schemes. Here we investigated the stability of salt marsh (Spartinaalterniflora) sediment C levels following seagrass (Thallasiatestudinum) wrack accumulation; a form of disturbance common throughout the world that removes large areas of plant biomass in salt marshes. At our study site (St Joseph Bay, Florida, USA), we recorded 296 patches (7.5 ± 2.3 m(2) mean area ± SE) of vegetation loss (aged 3-12 months) in a salt marsh meadow the size of a soccer field (7 275 m(2)). Within these disturbed patches, levels of organic C in the subsurface zone (1-5 cm depth) were ~30% lower than the surrounding undisturbed meadow. Subsequent analyses showed that the decline in subsurface C levels in disturbed patches was due to loss of below-ground plant (salt marsh) biomass, which otherwise forms the main component of the long-term 'refractory' C stock. We conclude that disturbance to salt marsh habitat due to wrack accumulation can cause significant release of below-ground C; which could shift salt marshes from C sinks to C sources, depending on the intensity and scale of disturbance. This mechanism of C release is likely to increase in the future due to sea level rise; which could increase wrack production due to increasing storminess, and will facilitate delivery of wrack into salt marsh zones due to higher and more frequent inundation.

Examining the relationship between workplace support and life satisfaction: the mediating role of job satisfaction

This paper examines the influence of perceived organizational support and perceived supervisor support on employee life satisfaction. Structural equation modelling on data from 393 nurses from two Chinese hospitals revealed that job satisfaction fully mediated the relationship between perceived organizational support and life satisfaction. In contrast, perceived supervisor support had a direct influence on life satisfaction rather than a mediated influence through job satisfaction. Our findings highlight the importance of separating the locus of support constructs when examining the impact of support on job and life satisfaction, given that perceived support has different effects depending upon the transmitter of that support. © 2014 Springer Science+Business Media Dordrecht.

A systematic review of how researchers characterize the school environment in determining its effect on student obesity

BACKGROUND: Obesity in early childhood is a robust predictor of obesity later in life. Schools provide unparalleled access to children and have subsequently become major intervention sites. However, empirical evidence supporting the effectiveness of school-based interventions against childhood obesity is of limited scope and unknown quality. The aim of this systematic review is to critically assess how researchers have characterized the school environment in determining its effect on childhood weight status in order to improve the quality and consistency of research in this area. We conducted a narrative review with a systematic search of the literature in line with PRISMA guidelines (2009). Original peer-reviewed research articles in English were searched from Medline, EMBASE, CENTRAL, CINAHL and PsycINFO databases from earliest record to January 2014. We included empirical research that reported at least one measure of the primary/elementary school environment and its relationship with at least one objective adiposity-related variable for students aged 4-12 years. Two authors independently extracted data on study design, school-level factors, student weight status, type of analysis and effect. RESULTS: Five studies met the inclusion criteria. Each study targeted different parts of the school environment and findings across the studies were not comparable. The instruments used to collect school-level data report no validity or reliability testing. CONCLUSIONS: Our review shows that researchers have used instruments of unknown quality to test if the school environment is a determinant of childhood obesity, which raises broader questions about the impact that schools can play in obesity prevention.

Does growth attract FDI?

FDI is seen widely as a vital source of investment, technology transfer, and growth. The factors that attract FDI have been a longstanding source of debate. The authors present a comprehensive assessment of the accumulated evidence on one factor, the success of economic growth in attracting FDI. Meta-regression analysis is applied to 946 estimates from 140 empirical studies. The results confirm that, on average, economic growth is an important determinant of FDI. Overall, there is a positive correlation between growth and FDI and this is much larger among single country case studies than with cross-country analysis.

Panel cointegration tests of the Fisher effect

Most empirical evidence suggests that the Fisher effect, stating that inflation and nominal interest rates should cointegrate with a unit slope on inflation, does not hold, a finding at odds with many theoretical models. This paper argues that these results can be attributed in part to the low power of univariate tests, and that the use of panel data can generate more powerful tests. For this purpose, we propose two new panel cointegration tests that can be applied under very general conditions, and that are shown by simulation to be more powerful than other existing tests. These tests are applied to a panel of quarterly data covering 20 OECD countries between 1980 and 2004. The evidence suggest that the Fisher effect cannot be rejected once the panel evidence on cointegration has been taken into account. Copyright © 2008 John Wiley & Sons, Ltd.

Opting only in: Contractarians, waiver of liability provisions, and the race to the bottom

This paper will test the core claim of scholars in the nexus of contracts tradition—that private ordering as a process of bargaining creates optimal rules. We do this by analyzing empirical evidence in the context of waiver of liability provisions. These provisions allow companies to eliminate monetary damages for breach of the duty of care through amendments to the articles of incorporation. With all states allowing some form of these provisions, they represent a good laboratory to examine the bargaining process between management and shareholders. The contractarian approach would suggest that shareholders negotiate with management to obtain agreements that are in their best interests. If a process of bargaining is at work as they claim, the opt-in process for waiver of liability provisions ought to generate a variety of approaches. Shareholders wanting a high degree of accountability would presumably not support a waiver of liability. In other instances, shareholders might favor them in order to attract or retain qualified managers. Still others would presumably want a mix, allowing waiver but only in specified circumstances.Our analysis reveals that the diversity predicted by a private ordering model is not borne out by the evidence with waiver of liability provisions for Fortune 100 companies. All states permit such provisions and in the Fortune 100, all but one company has them. Moreover, they are remarkably similar in effect, waiving liability to the fullest extent permitted by law. In other words, one categorical rule was merely replaced by another, dealing a significant blow to the contractarian thesis.

Using panel data to test for fiscal sustainability within the European Union

Most empirical evidence suggests that the sustainability hypothesis, stating that government revenues and expenditures should cointegrate with a unit slope on expenditures, does not hold within the European Union, a finding at odds with many theoretical models. This paper argues that these results can be attributed in part to the use of in-appropriate time-series techniques, and that the use of panel data can generate more accurate tests. By using newly devised panel unit-root and cointegration techniques it is shown that the sustainability hypothesis cannot be rejected when applied to a panel composed of 15 European countries between 1970 and 2004. © 2009 Mohr Siebeck.

Conserving koalas: A review of the contrasting regional trends, outlooks and policy challenges

The koala (Phascolarctos cinereus), one of the world's most iconic faunal species, was recently listed under Australian government legislation as vulnerable in the northern states of Queensland and New South Wales and in the Australian Capital Territory, but not in the southern states of Victoria and South Australia. This review synthesises empirical evidence of regional koala population trends, their conservation outlook, and associated policy challenges. Population declines are common in the northern half of the koala's range, where habitat loss, hotter droughts, disease, dog attacks and vehicle collisions are the major threats. In contrast, some southern populations are locally overabundant and are now subject to managed declines. The koala presents the problem of managing a wide-ranging species that now primarily occurs in human-modified landscapes, some of which are rapidly urbanising or subject to large-scale agricultural and mining developments. Climate change is a major threat to both northern and southern populations. The implementation of policy to conserve remaining koala habitat and restore degraded habitat is critical to the success of koala conservation strategies, but habitat conservation alone will not resolve the issues of koala conservation. There needs to be concerted effort to reduce the incidence of dog attack and road-related mortality, disease prevalence and severity, and take into account new threats of climate change and mining. Many of the complex conservation and policy challenges identified here have broader significance for other species whose population trends, and the nature of the threatening processes, vary from region to region, and through time.